[libpng17] Imported from libpng-1.7.0beta41.tar

needed by png_reciprocal2().
Added #ifdef PNG_16BIT_SUPPORTED/#endif around png_log16bit() and
    png_do_swap().

ANNOUNCE

@@ -1,5 +1,5 @@
 
-Libpng 1.7.0beta08 - April 14, 2013
+Libpng 1.7.0beta41 - November 7, 2014
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -9,19 +9,20 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.7.0beta08.tar.xz (LZMA-compressed, recommended)
-   1.7.0beta08.tar.gz
+   1.7.0beta41.tar.xz (LZMA-compressed, recommended)
+   1.7.0beta41.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lp170b08.7z  (LZMA-compressed, recommended)
-   lp170b08.zip
+   lp170b41.7z  (LZMA-compressed, recommended)
+   lp170b41.zip
 
 Other information:
 
-   1.7.0beta08-README.txt
-   1.7.0beta08-LICENSE.txt
+   1.7.0beta41-README.txt
+   1.7.0beta41-LICENSE.txt
+   libpng-1.7.0beta41-*.asc (armored detached GPG signatures)
 
 Changes since the last public release (1.6.0):
 
@@ -111,7 +112,9 @@ Version 1.7.0alpha07 [January 10, 2013]
     programs to generate and test a PNG which should have the problem.
 
 Version 1.7.0alpha08 [January 17, 2013]
-  Corrected previous attempt at overflow detection in png_set_unknown_chunks().
+  Corrected previous attempt at overflow detection in png_set_unknown_chunks()
+  (CVE-2013-7353).  Added overflow detection in png_set_sPLT() and
+  png_set_text_2() (CVE-2013-7354).
 
 Version 1.7.0alpha09 [January 21, 2013]
   Pulled changes to multi-chunk handling from libpng-1.6.0beta40.
@@ -249,7 +252,400 @@ Version 1.7.0beta07 [April 14, 2013]
     (Flavio Medeiros).
   Corrected length written to uncompressed iTXt chunks (Samuli Suominen).
 
-Version 1.7.0beta08 [April 14, 2013]
+Version 1.7.0beta08 [April 18, 2013]
+  Added contrib/tools/fixitxt.c, to repair the erroneous iTXt chunk length
+    written by libpng-1.6.0 and 1.6.1.
+  Disallow storing sRGB information when the sRGB is not supported.
+
+Version 1.7.0beta09 [April 24, 2013]
+  Exposed PNG chunk types in png.h
+  Modified png_uint_32 macros/code to make as few assumptions as possible
+  Revised stack marking in arm/filter_neon.S and configure.ac
+  Ensure that NEON filter stuff is completely disabled when switched 'off'.
+    Previously the ARM NEON specific files were still built if the option
+    was switched 'off' as opposed to being explicitly disabled.
+
+Version 1.7.0beta10 [April 24, 2013]
+  Attempt to fix the PNG_ARM_NEON configuration mess.
+
+Version 1.7.0beta11 [April 26, 2013]
+  Test for 'arm*', not just 'arm' in the host_cpu configure variable.
+
+Version 1.7.0beta12 [April 30, 2013]
+  Added png_app_warning for out-of-range unknown chunk index in
+    png_set_unknown_chunk_location().
+  Expanded manual paragraph about writing private chunks.
+  Avoid dereferencing NULL pointer possibly returned from
+     png_create_write_struct() (Andrew Church).
+
+Version 1.7.0beta13 [May 12, 2013]
+  Revised contrib/pngminim/*/makefile to generate pnglibconf.h with the
+    right zlib header files.
+  Separated CPPFLAGS and CFLAGS in contrib/pngminim/*/makefile
+  Updated contrib/pngminus/pnm2png.c (Paul Stewart):
+    Check for EOF
+    Ignore "#" delimited comments in input file to pnm2png.c.
+    Fixed whitespace handling
+    Added a call to png_set_packing()
+    Initialize dimension values so if sscanf fails at least we have known
+      invalid values.
+  Calculate our own zlib windowBits when decoding rather than trusting the
+    CMF bytes in the PNG datastream.
+  Added an option to force maximum window size for inflating, which was
+    the behavior of libpng15 and earlier.
+  Added png-fix-itxt and png-fix-too-far-back to the built programs and
+    removed warnings from the source code and timepng that are revealed as
+    a result.
+  Detect wrong libpng versions linked to png-fix-too-far-back, which currently
+    only works with libpng versions that can be made to reliably fail when
+    the deflate data contains an out-of-window reference.  This means only
+    1.6 and later.
+  Attempt to detect configuration issues with png-fix-too-far-back, which
+    requires both the correct libpng and the correct zlib to function
+    correctly.
+  Check ZLIB_VERNUM for mismatches, enclose #error in quotes
+  Added information in the documentation about problems with and fixes for
+    the bad CRC and bad iTXt chunk situations.
+
+Version 1.7.0beta14 [June 8, 2013]
+  Removed a redundant test in png_set_IHDR().
+  Added set(CMAKE_CONFIGURATION_TYPES ...) to CMakeLists.txt (Andrew Hundt)
+  Deleted set(CMAKE_BUILD_TYPE) block from CMakeLists.txt
+  Enclose the prototypes for the simplified write API in #ifdef STDIO/#endif
+  Make ARM NEON support work at compile time (not just configure time).
+    This moves the test on __ARM_NEON__ into pngconf.h to avoid issues when
+    using a compiler that compiles for multiple architectures at one time.
+  Removed PNG_FILTER_OPTIMIZATIONS and PNG_ARM_NEON_SUPPORTED from
+    pnglibconf.h, allowing more of the decisions to be made internally
+    (pngpriv.h) during the compile.  Without this, symbol prefixing is broken
+    under certain circumstances on ARM platforms.  Now only the API parts of
+    the optimizations ('check' vs 'api') are exposed in the public header files
+    except that the new setting PNG_ARM_NEON_OPT documents how libpng makes the
+    decision about whether or not to use the optimizations.
+  Protect symbol prefixing against CC/CPPFLAGS/CFLAGS useage.
+    Previous iOS/Xcode fixes for the ARM NEON optimizations moved the test
+    on __ARM_NEON__ from configure time to compile time.  This breaks symbol
+    prefixing because the definition of the special png_init_filter_functions
+    call was hidden at configure time if the relevant compiler arguments are
+    passed in CFLAGS as opposed to CC.  This change attempts to avoid all
+    the confusion that would result by declaring the init function even when
+    it is not used, so that it will always get prefixed.
+
+Version 1.7.0beta15 [June 18, 2013]
+  Revised libpng.3 so that "doclifter" can process it.
+
+Version 1.7.0beta16 [July 5, 2013]
+  Revised example.c to illustrate use of PNG_DEFAULT_sRGB and PNG_GAMMA_MAC_18
+    as parameters for png_set_gamma().  These have been available since
+    libpng-1.5.4.
+  Renamed contrib/tools/png-fix-too-far-back.c to pngfix.c and revised it
+    to check all compressed chunks known to libpng.
+  Updated documentation to show default behavior of benign errors correctly.
+  Added perfect hash code generation for lists of PNG chunks. This is
+    a work in progress; checked in for use in pngfix.c
+  Ported ARM no-read patch from libpng16.
+  Ported pngfix.c patches from libpng16.
+
+Version 1.7.0beta17 [August 21, 2013]
+  Revised manual about changes in iTXt chunk handling made in libpng-1.6.0.
+  Added "/* SAFE */" comments in pngrutil.c and pngrtran.c where warnings
+    may be erroneously issued by code-checking applications.
+  Added information about png_set_options() to the manual.
+  Delay calling png_init_filter_functions() until a row with nonzero filter
+    is found.
+
+Version 1.7.0beta18 [September 16, 2013]
+  Fixed inconsistent conditional compilation of png_chunk_unknown_handling()
+    prototype, definition, and usage.  Made it depend on
+    PNG_HANDLE_AS_UNKNOWN_SUPPORTED everywhere.
+
+Version 1.7.0beta19 [September 30, 2013]
+  Reverted the change to unknown handling #defines; the change breaks 'NOREAD'
+    builds.
+  Fixed default behavior of ARM_NEON_API. If the ARM NEON API option is
+    compiled without the CHECK option it defaulted to on, not off.
+  Catch up with recent libpng16 changes; unknown handling and spelling
+    corrections
+  Avoid up-cast warnings in pngvalid.c. On ARM the alignment requirements of
+    png_modifier are greater than that of png_store and as a consequence
+    compilation of pngvalid.c results in a warning about increased alignment
+    requirements because of the bare cast to (png_modifier*).  The code is
+    safe, because the pointer is known to point to a stack allocated
+    png_modifier, but this change avoids the warning.
+  Fixed some grammatical changes and updated the png chunks list.
+
+Version 1.7.0beta20 [October 13, 2013]
+  Made changes for compatibility with automake 1.14:
+    1) Added the 'compile' program to the list of programs that must be cleaned
+       in autogen.sh
+    2) Added 'subdir-objects' which causes .c files in sub-directories to be
+       compiled such that the corresponding .o files are also in the
+       sub-directory.  This is because automake 1.14 warns that the
+       current behavior of compiling to the top level directory may be removed
+       in the future.
+    3) Updated dependencies on pnglibconf.h to match the new .o locations and
+       added all the files in contrib/libtests and contrib/tools that depend
+       on pnglibconf.h
+    4) Added 'BUILD_SOURCES = pnglibconf.h'; this is the automake recommended
+       way of handling the dependencies of sources that are machine generated;
+       unfortunately it only works if the user does 'make all' or 'make check',
+       so the dependencies (3) are still required.
+  Cleaned up (char*) casts of zlib messages. The latest version of the Intel C
+    compiler complains about casting a string literal as (char*), so copied the
+    treatment of z_const from the library code into pngfix.c
+  Simplified error message code in pngunknown. The simplification has the
+    useful side effect of avoiding a bogus warning generated by the latest
+    version of the Intel C compiler (it objects to
+    condition ? string-literal : string-literal).
+  Make autogen.sh work with automake 1.13 as well as 1.14. Do this by always
+    removing the 1.14 'compile' script but never checking for it.
+
+Version 1.7.0beta21 [November 2, 2013]
+  Added ARMv8 support (James Yu <james.yu at linaro.org>).  Added file
+    arm/filter_neon_intrinsics.c; enable with -mfpu=neon.
+  Revised pngvalid to generate size images with as many filters as it can
+    manage, limited by the number of rows.
+  Cleaned up ARM NEON compilation handling. The tests are now in pngpriv.h
+    and detect the broken GCC compilers.
+  Allow clang derived from older GCC versions to use ARM intrinsics. This
+    causes all clang builds that use -mfpu=neon to use the intrinsics code,
+    not the assembler code.  This has only been tested on iOS 7. It may be
+    necessary to exclude some earlier clang versions but this seems unlikely.
+  Changed NEON implementation selection mechanism. This allows assembler
+    or intrinsics to be turned on at compile time during the build by defining
+    PNG_ARM_NEON_IMPLEMENTATION to the correct value (2 or 1).  This macro
+    is undefined by default and the build type is selected in pngpriv.h.
+
+Version 1.7.0beta22 [November 7, 2013]
+  Fixed #include in filter_neon_intrinsics.c and ctype macros. The ctype char
+    checking macros take an unsigned char argument, not a signed char.
+
+Version 1.7.0beta23 [November 24, 2013]
+  Changed #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED in pngpread.c to
+    #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED to be consistent with
+    what is in pngpriv.h.
+  Moved prototype for png_handle_unknown() in pngpriv.h outside of
+    the #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED/#endif block.
+  Added "-Wall" to CFLAGS in contrib/pngminim/*/makefile
+  Conditionally compile some unused functions reported by -Wall in
+    pngminim.
+  Fixed 'minimal' builds. Various obviously useful minimal configurations
+    don't build because of missing contrib/libtests test programs and
+    overly complex dependencies in scripts/pnglibconf.dfa. This change
+    adds contrib/conftest/*.dfa files that can be used in automatic build
+    scripts to ensure that these configurations continue to build.
+  Enabled WRITE_INVERT and WRITE_PACK in contrib/pngminim/encoder.
+  Fixed pngvalid 'fail' function declaration on the Intel C Compiler.
+    This reverts to the previous 'static' implementation and works round
+    the 'unused static function' warning by using PNG_UNUSED().
+
+Version 1.7.0beta24 [December 15, 2013]
+  Removed or marked PNG_UNUSED some harmless "dead assignments" reported
+    by clang scan-build.
+  Changed tabs to 3 spaces in png_debug macros and changed '"%s"m'
+    to '"%s" m' to improve portability among compilers.
+  Changed png_free_default() to free() in pngtest.c
+  Tidied up pngfix inits and fixed pngtest no-write builds.
+  Bookkeeping: Moved functions around (no changes). Moved transform
+    function definitions before the place where they are called so that
+    they can be made static. Move the intrapixel functions and the
+    grayscale palette builder out of the png?tran.c files. The latter
+    isn't a transform function and is no longer used internally, and the
+    former MNG specific functions are better placed in pngread/pngwrite.c
+  Made transform implementation functions static. This makes the internal
+    functions called by png_do_{read|write}_transformations static. On an
+    x86-64 DLL build (Gentoo Linux) this reduces the size of the text
+    segment of the DLL by 1208 bytes, about 0.6%. It also simplifies
+    maintenance by removing the declarations from pngpriv.h and allowing
+    easier changes to the internal interfaces.
+  Handle zero-length PLTE chunk or NULL palette with png_error()
+    instead of png_chunk_report(), which by default issues a warning
+    rather than an error, leading to later reading from a NULL pointer
+    (png_ptr->palette) in png_do_expand_palette(). This is CVE-2013-6954
+    and VU#650142.  Libpng-1.6.1 through 1.6.7 and libpng-1.7.0beta03
+    through 1.7.0beta23 are vulnerable.  Libpng-1.6.0 and earlier do not
+    have the bug.
+
+Version 1.7.0beta25 [December 26, 2013]
+  Merged files with version 1.6.8 that have not changed since then.
+  Rebuilt configure scripts with automake-1.14.1 and autoconf-2.69
+
+Version 1.7.0beta26 [January 1, 2014]
+  Added libpng 1.5 checks to pngvalid.c
+  Merged with 1.5 and 1.6 changes to create a single pngvalid.c
+  Added dSIG to chunk list in png.h
+  Removed #error macro from contrib/tools/pngfix.c (Thomas Klausner).
+  Merged pngrio.c, pngtrans.c, and pngwio.c with libpng-1.6.9
+  Fixed test programs for interlace options. Made pngvalid.c and
+    pngtest.c work correctly when READ_INTERLACING and/or WRITE_INTERLACING
+    are switched off.
+  Changed pngvalid.c to support libpng 1.5, which does not support
+    the PNG_MAXIMUM_INFLATE_WINDOW option, so #define it out when
+    appropriate in pngvalid.c
+  Allow unversioned links created on install to be disabled in configure.
+    In configure builds 'make install' changes/adds links like png.h
+    and libpng.a to point to the newly installed, versioned, files (e.g.
+    libpng17/png.h and libpng17.a). Three new configure options and some
+    rearrangement of Makefile.am allow creation of these links to be disabled.
+
+Version 1.7.0beta27 [January 10, 2014]
+  Removed potentially misleading warning from png_check_IHDR().
+
+Version 1.7.0beta28 [January 20, 2014]
+  Updated scripts/makefile.* to use CPPFLAGS (Cosmin).
+  Added clang attribute support (Cosmin).
+
+Version 1.7.0beta29 [January 30, 2014]
+  Quiet an uninitialized memory warning from VS2013 in png_get_png().
+
+Version 1.7.0beta30 [February 2, 2014]
+  Fixed a large number of instances where PNGCBAPI was omitted from
+    function definitions.
+  Added pngimage test program for png_read_png and png_write_png. This
+    is a work-in-progress; no tests are run automatically at present and
+    the program by virtue of exhaustively testing all the transforms is
+    very slow.
+
+Version 1.7.0beta31 [February 6, 2014]
+  Make png_read_png() and png_write_png() prototypes in png.h depend
+    upon PNG_READ_SUPPORTED and PNG_WRITE_SUPPORTED.
+  Removed dependence on !PNG_READ_EXPAND_SUPPORTED for calling
+    png_set_packing() in png_read_png().
+  Completed full working pngimage test program and added two test scripts.
+  Fixed combination of ~alpha with shift. On read invert alpha, processing
+    occurred after shift processing, which causes the final values to be
+    outside the range that should be produced by the shift. Reversing the
+    order on read makes the two transforms work together correctly and mirrors
+    the order used on write.
+  Do not read invalid sBIT chunks. Previously libpng only checked sBIT
+    values on write, so a malicious PNG writer could therefore cause
+    the read code to return an invalid sBIT chunk, which might lead to
+    application errors or crashes.  Such chunks are now skipped (with
+    chunk_benign_error).
+  Restored a line, "c = b;", that was inadvertently deleted from the
+    PAETH filtering code from libpng-1.7.0beta24/pngrutil.c. Deleted
+    the other instance of "c = b;" which is the one that triggered a
+    scan-build warning.
+  Support builds with unsupported PNG_TRANSFORM_* values.  All of the
+    PNG_TRANSFORM_* values are always defined in png.h and, because they
+    are used for both read and write in some cases, it is not reliable
+    to #if out ones that are totally unsupported. This change adds error
+    detection in png_read_image() and png_write_image() to do a
+    png_app_error() if the app requests something that cannot be done
+    and it adds corresponding code to pngimage.c to handle such options
+    by not attempting to test them.
+
+Version 1.7.0beta32 [February 26, 2014]
+  Moved redefines of png_error(), png_warning(), png_chunk_error(),
+    and png_chunk_warning() from pngpriv.h to png.h to make them visible
+    to libpng-calling applications.
+  Moved OS dependent code from arm/arm_init.c, to allow the included
+    implementation of the ARM NEON discovery function to be set at
+    build-time and provide sample implementations from the current code in the
+    contrib/arm-neon subdirectory. The __linux__ code has also been changed to
+    compile and link on Android by using /proc/cpuinfo, and the old linux code
+    is in contrib/arm-neon/linux-auxv.c.  The new code avoids POSIX and Linux
+    dependencies apart from opening /proc/cpuinfo and is C90 compliant.
+  Check for info_ptr == NULL early in png_read_end() so we don't need to
+    run all the png_handle_*() and depend on them to return if info_ptr == NULL.
+    This improves the performance of png_read_end(png_ptr, NULL) and makes
+    it more robust against future programming errors.
+  Check for __has_extension before using it in pngconf.h, to
+    support older Clang versions (Jeremy Sequoia).
+  Use a user warning handler in contrib/gregbook/readpng2.c instead of default,
+    so warnings will be put on stderr even if libpng has CONSOLE_IO disabled.
+  Added png_ptr->process_mode = PNG_READ_IDAT_MODE in png_push_read_chunk
+    after recognizing the IDAT chunk, which avoids an infinite loop while
+    reading a datastream whose first IDAT chunk is of zero-length.
+    This fixes CERT VU#684412 and CVE-2014-0333.
+  Don't recognize known sRGB profiles as sRGB if they have been hacked,
+    but don't reject them and don't issue a copyright violation warning.
+  Minor editing of contrib/arm-neon/README and contrib/examples/*.c
+  Moved some documentation from png.h to libpng.3 and libpng-manual.txt
+
+Version 1.7.0beta33 [February 27, 2014]
+  Fixed typos in the manual and in scripts/pnglibconf.dfa (CFLAGS -> CPPFLAGS
+    and PNG_USR_CONFIG -> PNG_USER_CONFIG).
+
+Version 1.7.0beta34 [March 17, 2014]
+  Treat CRC error handling with png_set_crc_action(), instead of with
+    png_set_benign_errors(), which has been the case since libpng-1.6.0beta18.
+  Use "if (value != 0)" instead of "if (value)" consistently.
+  Changed ZlibSrcDir from 1.2.5 to 1.2.8 in projects/vstudio.
+  Moved configuration information from the manual to the INSTALL file.
+
+Version 1.7.0beta35 [August 6, 2014]
+  Removed #if/#else/#endif from inside two pow() calls in pngvalid.c because
+    they were handled improperly by Portland Group's PGI-14.1 - PGI-14.3
+    when using its "__builtin_pow()" function.
+  Silence 'unused parameter' build warnings (Cosmin).
+  $(CP) is now used alongside $(RM_F).  Also, use 'copy' instead
+    of 'cp' where applicable, and applied other minor makefile changes.
+  Don't warn about invalid dimensions exceeding user limits.
+  Allow an easy replacement of the default pre-built configuration
+    header with a custom header, via the make PNGLIBCONF_H_PREBUILT
+    macro.
+  Fixed a typo in pngrutil.c, introduced in libpng-1.5.6, that interferes
+    with "blocky" expansion of sub-8-bit interlaced PNG files (Eric Huss).
+  Removed scripts/makefile.elf. It has not worked since libpng-1.5.0beta14
+    due to elimination of the PNG_FUNCTION_EXPORT and PNG_DATA_EXPORT
+    definitions from pngconf.h.
+  Ensure that CMakeLists.txt makes the target "lib" directory before making
+    symbolic link into it (SourceForge bug report #226 by Rolf Timmermans).
+  Added opinion that the ECCN (Export Control Classification Number) for
+    libpng is EAR99 to the README file.
+
+Version 1.7.0beta36 [September 27, 2014]
+  Updated scripts/makefiles from libpng-1.6.13beta04.
+  Minor updates to the manual from libpng-1.6.14beta04.
+  Fixed incorrect handling of the iTXt compression flag in pngrutil.c
+    (bug report by Shunsaku Hirata).  Bug was introduced in libpng-1.6.0.
+
+Version 1.7.0beta37 [September 28, 2014]
+  Merged scripts/*, pngvalid.c and pngfix.c with libpng-1.6.14beta04.
+
+Version 1.7.0beta38 [October 17, 2014]
+  Added "option READ_iCCP enables READ_COMPRESSED_TEXT" to pnglibconf.dfa
+  Removed unused "text_len" parameter from private function png_write_zTXt().
+  Conditionally compile some code in png_deflate_claim(), when
+    PNG_WARNINGS_SUPPORTED and PNG_ERROR_TEXT_SUPPORTED are disabled.
+  Replaced repeated code in pngpread.c with PNG_PUSH_SAVE_BUFFER_IF_FULL.
+  Added "chunk iTXt enables TEXT" and "chunk zTXt enables TEXT"
+    to pnglibconf.dfa.
+  Removed "option READ_COMPRESSED_TEXT enables READ_TEXT" from pnglibconf.dfa,
+    to make it possible to configure a libpng that supports iCCP but not TEXT.
+  Removed "option WRITE_COMPRESSED_TEXT enables WRITE_TEXT" from pnglibconf.dfa
+  Only mark text chunks as written after successfully writing them.
+
+Version 1.7.0beta39 [November 1, 2014]
+  Ported cosmetic changes from libpng-1.6.15beta02.
+
+Version 1.7.0beta40 [November 6, 2014]
+  Made a one-line revision to configure.ac to support ARM on aarch64
+    (bug report by Marcin Juszkiewicz, fix by John Bowler).
+  Use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING in
+    example.c, pngtest.c, and applications in the contrib directory.
+  Avoid out-of-bounds memory access in png_user_version_check().
+  Simplified and future-proofed png_user_version_check().
+  Fixed GCC unsigned int->float warnings. Various versions of GCC
+    seem to generate warnings when an unsigned value is implicitly
+    converted to double. This is probably a GCC bug but this change
+    avoids the issue by explicitly converting to (int) where safe.
+  Free all allocated memory in pngimage. The file buffer cache was left
+    allocated at the end of the program, harmless but it causes memory
+    leak reports from clang.
+  Fixed array size calculations to avoid warnings. At various points
+    in the code the number of elements in an array is calculated using
+    sizeof.  This generates a compile time constant of type (size_t) which
+    is then typically assigned to an (unsigned int) or (int). Some versions
+    of GCC on 64-bit systems warn about the apparent narrowing, even though
+    the same compiler does apparently generate the correct, in-range,
+    numeric constant.  This adds appropriate, safe, casts to make the
+    warnings go away.
+
+Version 1.7.0beta41 [November 7, 2014]
+  Added #ifdef PNG_16BIT_SUPPORTED/#endif around png_log16bit() and
+    png_do_swap().
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CHANGES

@@ -4046,7 +4046,9 @@ Version 1.6.0beta17 [March 10, 2012]
   Deflate/inflate was reworked to move common zlib calls into single
     functions [rw]util.c.  A new shared keyword check routine was also added
     and the 'zbuf' is no longer allocated on progressive read.  It is now
-    possible to call png_inflate() incrementally.
+    possible to call png_inflate() incrementally.  A warning is no longer
+    issued if the language tag or translated keyword in the iTXt chunk
+    has zero length.
   If benign errors are disabled use maximum window on ancilliary inflate.
     This works round a bug introduced in 1.5.4 where compressed ancillary
     chunks could end up with a too-small windowBits value in the deflate
@@ -4398,7 +4400,9 @@ Version 1.7.0alpha07 [January 10, 2013]
     programs to generate and test a PNG which should have the problem.
 
 Version 1.7.0alpha08 [January 17, 2013]
-  Corrected previous attempt at overflow detection in png_set_unknown_chunks().
+  Corrected previous attempt at overflow detection in png_set_unknown_chunks()
+  (CVE-2013-7353).  Added overflow detection in png_set_sPLT() and
+  png_set_text_2() (CVE-2013-7354).
 
 Version 1.7.0alpha09 [January 21, 2013]
   Pulled changes to multi-chunk handling from libpng-1.6.0beta40.
@@ -4536,7 +4540,401 @@ Version 1.7.0beta07 [April 14, 2013]
     (Flavio Medeiros).
   Corrected length written to uncompressed iTXt chunks (Samuli Suominen).
 
-Version 1.7.0beta08 [April 14, 2013]
+Version 1.7.0beta08 [April 18, 2013]
+  Added contrib/tools/fixitxt.c, to repair the erroneous iTXt chunk length
+    written by libpng-1.6.0 and 1.6.1.
+  Disallow storing sRGB information when the sRGB is not supported.
+
+Version 1.7.0beta09 [April 24, 2013]
+  Exposed PNG chunk types in png.h
+  Modified png_uint_32 macros/code to make as few assumptions as possible
+    about the hardware.
+  Revised stack marking in arm/filter_neon.S and configure.ac.
+  Ensure that NEON filter stuff is completely disabled when switched 'off'.
+    Previously the ARM NEON specific files were still built if the option
+    was switched 'off' as opposed to being explicitly disabled.
+
+Version 1.7.0beta10 [April 24, 2013]
+  Attempt to fix the PNG_ARM_NEON configuration mess.
+
+Version 1.7.0beta11 [April 26, 2013]
+  Test for 'arm*', not just 'arm' in the host_cpu configure variable.
+
+Version 1.7.0beta12 [April 30, 2013]
+  Added png_app_warning for out-of-range unknown chunk index in
+    png_set_unknown_chunk_location().
+  Expanded manual paragraph about writing private chunks.
+  Avoid dereferencing NULL pointer possibly returned from
+     png_create_write_struct() (Andrew Church).
+
+Version 1.7.0beta13 [May 12, 2013]
+  Revised contrib/pngminim/*/makefile to generate pnglibconf.h with the
+    right zlib header files.
+  Separated CPPFLAGS and CFLAGS in contrib/pngminim/*/makefile
+  Updated contrib/pngminus/pnm2png.c (Paul Stewart):
+    Check for EOF
+    Ignore "#" delimited comments in input file to pnm2png.c.
+    Fixed whitespace handling
+    Added a call to png_set_packing()
+    Initialize dimension values so if sscanf fails at least we have known
+      invalid values.
+  Calculate our own zlib windowBits when decoding rather than trusting the
+    CMF bytes in the PNG datastream.
+  Added an option to force maximum window size for inflating, which was
+    the behavior of libpng15 and earlier.
+  Added png-fix-itxt and png-fix-too-far-back to the built programs and
+    removed warnings from the source code and timepng that are revealed as
+    a result.
+  Detect wrong libpng versions linked to png-fix-too-far-back, which currently
+    only works with libpng versions that can be made to reliably fail when
+    the deflate data contains an out-of-window reference.  This means only
+    1.6 and later.
+  Attempt to detect configuration issues with png-fix-too-far-back, which
+    requires both the correct libpng and the correct zlib to function
+    correctly.
+  Check ZLIB_VERNUM for mismatches, enclose #error in quotes
+  Added information in the documentation about problems with and fixes for
+    the bad CRC and bad iTXt chunk situations.
+
+Version 1.7.0beta14 [June 8, 2013]
+  Removed a redundant test in png_set_IHDR().
+  Added set(CMAKE_CONFIGURATION_TYPES ...) to CMakeLists.txt (Andrew Hundt)
+  Deleted set(CMAKE_BUILD_TYPE) block from CMakeLists.txt
+  Enclose the prototypes for the simplified write API in #ifdef STDIO/#endif
+  Make ARM NEON support work at compile time (not just configure time).
+    This moves the test on __ARM_NEON__ into pngconf.h to avoid issues when
+    using a compiler that compiles for multiple architectures at one time.
+  Removed PNG_FILTER_OPTIMIZATIONS and PNG_ARM_NEON_SUPPORTED from
+    pnglibconf.h, allowing more of the decisions to be made internally
+    (pngpriv.h) during the compile.  Without this, symbol prefixing is broken
+    under certain circumstances on ARM platforms.  Now only the API parts of
+    the optimizations ('check' vs 'api') are exposed in the public header files
+    except that the new setting PNG_ARM_NEON_OPT documents how libpng makes the
+    decision about whether or not to use the optimizations.
+  Protect symbol prefixing against CC/CPPFLAGS/CFLAGS useage.
+    Previous iOS/Xcode fixes for the ARM NEON optimizations moved the test
+    on __ARM_NEON__ from configure time to compile time.  This breaks symbol
+    prefixing because the definition of the special png_init_filter_functions
+    call was hidden at configure time if the relevant compiler arguments are
+    passed in CFLAGS as opposed to CC.  This change attempts to avoid all
+    the confusion that would result by declaring the init function even when
+    it is not used, so that it will always get prefixed.
+
+Version 1.7.0beta15 [June 18, 2013]
+  Revised libpng.3 so that "doclifter" can process it.
+
+Version 1.7.0beta16 [July 5, 2013]
+  Revised example.c to illustrate use of PNG_DEFAULT_sRGB and PNG_GAMMA_MAC_18
+    as parameters for png_set_gamma().  These have been available since
+    libpng-1.5.4.
+  Renamed contrib/tools/png-fix-too-far-back.c to pngfix.c and revised it
+    to check all compressed chunks known to libpng.
+  Updated documentation to show default behavior of benign errors correctly.
+  Added perfect hash code generation for lists of PNG chunks. This is
+    a work in progress; checked in for use in pngfix.c
+  Ported ARM no-read patch from libpng16.
+  Ported pngfix.c patches from libpng16.
+
+Version 1.7.0beta17 [August 21, 2013]
+  Revised manual about changes in iTXt chunk handling made in libpng-1.6.0.
+  Added "/* SAFE */" comments in pngrutil.c and pngrtran.c where warnings
+    may be erroneously issued by code-checking applications.
+  Added information about png_set_options() to the manual.
+  Delay calling png_init_filter_functions() until a row with nonzero filter
+    is found.
+
+Version 1.7.0beta18 [September 16, 2013]
+  Fixed inconsistent conditional compilation of png_chunk_unknown_handling()
+    prototype, definition, and usage.  Made it depend on
+    PNG_HANDLE_AS_UNKNOWN_SUPPORTED everywhere.
+
+Version 1.7.0beta19 [September 30, 2013]
+  Reverted the change to unknown handling #defines; the change breaks 'NOREAD'
+    builds.
+  Fixed default behavior of ARM_NEON_API. If the ARM NEON API option is
+    compiled without the CHECK option it defaulted to on, not off.
+  Catch up with recent libpng16 changes; unknown handling and spelling
+    corrections
+  Avoid up-cast warnings in pngvalid.c. On ARM the alignment requirements of
+    png_modifier are greater than that of png_store and as a consequence
+    compilation of pngvalid.c results in a warning about increased alignment
+    requirements because of the bare cast to (png_modifier*).  The code is
+    safe, because the pointer is known to point to a stack allocated
+    png_modifier, but this change avoids the warning.
+  Fixed some grammatical changes and updated the png chunks list.
+
+Version 1.7.0beta20 [October 13, 2013]
+  Made changes for compatibility with automake 1.14:
+    1) Added the 'compile' program to the list of programs that must be cleaned
+       in autogen.sh
+    2) Added 'subdir-objects' which causes .c files in sub-directories to be
+       compiled such that the corresponding .o files are also in the
+       sub-directory.  This is because automake 1.14 warns that the
+       current behavior of compiling to the top level directory may be removed
+       in the future.
+    3) Updated dependencies on pnglibconf.h to match the new .o locations and
+       added all the files in contrib/libtests and contrib/tools that depend
+       on pnglibconf.h
+    4) Added 'BUILD_SOURCES = pnglibconf.h'; this is the automake recommended
+       way of handling the dependencies of sources that are machine generated;
+       unfortunately it only works if the user does 'make all' or 'make check',
+       so the dependencies (3) are still required.
+  Cleaned up (char*) casts of zlib messages. The latest version of the Intel C
+    compiler complains about casting a string literal as (char*), so copied the
+    treatment of z_const from the library code into pngfix.c
+  Simplified error message code in pngunknown. The simplification has the
+    useful side effect of avoiding a bogus warning generated by the latest
+    version of the Intel C compiler (it objects to
+    condition ? string-literal : string-literal).
+  Make autogen.sh work with automake 1.13 as well as 1.14. Do this by always
+    removing the 1.14 'compile' script but never checking for it.
+
+Version 1.7.0beta21 [November 2, 2013]
+  Added ARMv8 support (James Yu <james.yu at linaro.org>).  Added file
+    arm/filter_neon_intrinsics.c; enable with -mfpu=neon.
+  Revised pngvalid to generate size images with as many filters as it can
+    manage, limited by the number of rows.
+  Cleaned up ARM NEON compilation handling. The tests are now in pngpriv.h
+    and detect the broken GCC compilers.
+  Allow clang derived from older GCC versions to use ARM intrinsics. This
+    causes all clang builds that use -mfpu=neon to use the intrinsics code,
+    not the assembler code.  This has only been tested on iOS 7. It may be
+    necessary to exclude some earlier clang versions but this seems unlikely.
+  Changed NEON implementation selection mechanism. This allows assembler
+    or intrinsics to be turned on at compile time during the build by defining
+    PNG_ARM_NEON_IMPLEMENTATION to the correct value (2 or 1).  This macro
+    is undefined by default and the build type is selected in pngpriv.h.
+
+Version 1.7.0beta22 [November 7, 2013]
+  Fixed #include in filter_neon_intrinsics.c and ctype macros. The ctype char
+    checking macros take an unsigned char argument, not a signed char.
+
+Version 1.7.0beta23 [November 24, 2013]
+  Changed #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED in pngpread.c to
+    #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED to be consistent with
+    what is in pngpriv.h.
+  Moved prototype for png_handle_unknown() in pngpriv.h outside of
+    the #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED/#endif block.
+  Added "-Wall" to CFLAGS in contrib/pngminim/*/makefile
+  Conditionally compile some unused functions reported by -Wall in
+    pngminim.
+  Fixed 'minimal' builds. Various obviously useful minimal configurations
+    don't build because of missing contrib/libtests test programs and
+    overly complex dependencies in scripts/pnglibconf.dfa. This change
+    adds contrib/conftest/*.dfa files that can be used in automatic build
+    scripts to ensure that these configurations continue to build.
+  Enabled WRITE_INVERT and WRITE_PACK in contrib/pngminim/encoder.
+  Fixed pngvalid 'fail' function declaration on the Intel C Compiler.
+    This reverts to the previous 'static' implementation and works round
+    the 'unused static function' warning by using PNG_UNUSED().
+
+Version 1.7.0beta24 [December 15, 2013]
+  Removed or marked PNG_UNUSED some harmless "dead assignments" reported
+    by clang scan-build.
+  Changed tabs to 3 spaces in png_debug macros and changed '"%s"m'
+    to '"%s" m' to improve portability among compilers.
+  Changed png_free_default() to free() in pngtest.c
+  Tidied up pngfix inits and fixed pngtest no-write builds.
+  Bookkeeping: Moved functions around (no changes). Moved transform
+    function definitions before the place where they are called so that
+    they can be made static. Move the intrapixel functions and the
+    grayscale palette builder out of the png?tran.c files. The latter
+    isn't a transform function and is no longer used internally, and the
+    former MNG specific functions are better placed in pngread/pngwrite.c
+  Made transform implementation functions static. This makes the internal
+    functions called by png_do_{read|write}_transformations static. On an
+    x86-64 DLL build (Gentoo Linux) this reduces the size of the text
+    segment of the DLL by 1208 bytes, about 0.6%. It also simplifies
+    maintenance by removing the declarations from pngpriv.h and allowing
+    easier changes to the internal interfaces.
+  Handle zero-length PLTE chunk or NULL palette with png_error()
+    instead of png_chunk_report(), which by default issues a warning
+    rather than an error, leading to later reading from a NULL pointer
+    (png_ptr->palette) in png_do_expand_palette(). This is CVE-2013-6954
+    and VU#650142.  Libpng-1.6.1 through 1.6.7 and libpng-1.7.0beta03
+    through 1.7.0beta23 are vulnerable.  Libpng-1.6.0 and earlier do not
+    have the bug.
+
+Version 1.7.0beta25 [December 26, 2013]
+  Merged files with version 1.6.8 that have not changed since then.
+  Rebuilt configure scripts with automake-1.14.1 and autoconf-2.69
+
+Version 1.7.0beta26 [January 1, 2014]
+  Added libpng 1.5 checks to pngvalid.c
+  Merged with 1.5 and 1.6 changes to create a single pngvalid.c
+  Added dSIG to chunk list in png.h
+  Removed #error macro from contrib/tools/pngfix.c (Thomas Klausner).
+  Merged pngrio.c, pngtrans.c, and pngwio.c with libpng-1.6.9
+  Fixed test programs for interlace options. Made pngvalid.c and
+    pngtest.c work correctly when READ_INTERLACING and/or WRITE_INTERLACING
+    are switched off.
+  Changed pngvalid.c to support libpng 1.5, which does not support
+    the PNG_MAXIMUM_INFLATE_WINDOW option, so #define it out when
+    appropriate in pngvalid.c
+  Allow unversioned links created on install to be disabled in configure.
+    In configure builds 'make install' changes/adds links like png.h
+    and libpng.a to point to the newly installed, versioned, files (e.g.
+    libpng17/png.h and libpng17.a). Three new configure options and some
+    rearrangement of Makefile.am allow creation of these links to be disabled.
+
+Version 1.7.0beta27 [January 10, 2014]
+  Removed potentially misleading warning from png_check_IHDR().
+
+Version 1.7.0beta28 [January 20, 2014]
+  Updated scripts/makefile.* to use CPPFLAGS (Cosmin).
+  Added clang attribute support (Cosmin).
+
+Version 1.7.0beta29 [January 30, 2014]
+  Quiet an uninitialized memory warning from VS2013 in png_get_png().
+
+Version 1.7.0beta30 [February 2, 2014]
+  Fixed a large number of instances where PNGCBAPI was omitted from
+    function definitions.
+  Added pngimage test program for png_read_png and png_write_png. This
+    is a work-in-progress; no tests are run automatically at present and
+    the program by virtue of exhaustively testing all the transforms is
+    very slow.
+
+Version 1.7.0beta31 [February 6, 2014]
+  Make png_read_png() and png_write_png() prototypes in png.h depend
+    upon PNG_READ_SUPPORTED and PNG_WRITE_SUPPORTED.
+  Removed dependence on !PNG_READ_EXPAND_SUPPORTED for calling
+    png_set_packing() in png_read_png().
+  Completed full working pngimage test program and added two test scripts.
+  Fixed combination of ~alpha with shift. On read invert alpha, processing
+    occurred after shift processing, which causes the final values to be
+    outside the range that should be produced by the shift. Reversing the
+    order on read makes the two transforms work together correctly and mirrors
+    the order used on write.
+  Do not read invalid sBIT chunks. Previously libpng only checked sBIT
+    values on write, so a malicious PNG writer could therefore cause
+    the read code to return an invalid sBIT chunk, which might lead to
+    application errors or crashes.  Such chunks are now skipped (with
+    chunk_benign_error).
+  Restored a line, "c = b;", that was inadvertently deleted from the
+    PAETH filtering code from libpng-1.7.0beta24/pngrutil.c. Deleted
+    the other instance of "c = b;" which is the one that triggered a
+    scan-build warning.
+  Support builds with unsupported PNG_TRANSFORM_* values.  All of the
+    PNG_TRANSFORM_* values are always defined in png.h and, because they
+    are used for both read and write in some cases, it is not reliable
+    to #if out ones that are totally unsupported. This change adds error
+    detection in png_read_image() and png_write_image() to do a
+    png_app_error() if the app requests something that cannot be done
+    and it adds corresponding code to pngimage.c to handle such options
+    by not attempting to test them.
+
+Version 1.7.0beta32 [February 26, 2014]
+  Moved redefines of png_error(), png_warning(), png_chunk_error(),
+    and png_chunk_warning() from pngpriv.h to png.h to make them visible
+    to libpng-calling applications.
+  Moved OS dependent code from arm/arm_init.c, to allow the included
+    implementation of the ARM NEON discovery function to be set at
+    build-time and provide sample implementations from the current code in the
+    contrib/arm-neon subdirectory. The __linux__ code has also been changed to
+    compile and link on Android by using /proc/cpuinfo, and the old linux code
+    is in contrib/arm-neon/linux-auxv.c.  The new code avoids POSIX and Linux
+    dependencies apart from opening /proc/cpuinfo and is C90 compliant.
+  Check for info_ptr == NULL early in png_read_end() so we don't need to
+    run all the png_handle_*() and depend on them to return if info_ptr == NULL.
+    This improves the performance of png_read_end(png_ptr, NULL) and makes
+    it more robust against future programming errors.
+  Check for __has_extension before using it in pngconf.h, to
+    support older Clang versions (Jeremy Sequoia).
+  Use a user warning handler in contrib/gregbook/readpng2.c instead of default,
+    so warnings will be put on stderr even if libpng has CONSOLE_IO disabled.
+  Added png_ptr->process_mode = PNG_READ_IDAT_MODE in png_push_read_chunk
+    after recognizing the IDAT chunk, which avoids an infinite loop while
+    reading a datastream whose first IDAT chunk is of zero-length.
+    This fixes CERT VU#684412 and CVE-2014-0333.
+  Don't recognize known sRGB profiles as sRGB if they have been hacked,
+    but don't reject them and don't issue a copyright violation warning.
+  Minor editing of contrib/arm-neon/README and contrib/examples/*.c
+  Moved some documentation from png.h to libpng.3 and libpng-manual.txt
+
+Version 1.7.0beta33 [February 27, 2014]
+  Fixed typos in the manual and in scripts/pnglibconf.dfa (CFLAGS -> CPPFLAGS
+    and PNG_USR_CONFIG -> PNG_USER_CONFIG).
+
+Version 1.7.0beta34 [March 17, 2014]
+  Treat CRC error handling with png_set_crc_action(), instead of with
+    png_set_benign_errors(), which has been the case since libpng-1.6.0beta18.
+  Use "if (value != 0)" instead of "if (value)" consistently.
+  Changed ZlibSrcDir from 1.2.5 to 1.2.8 in projects/vstudio.
+  Moved configuration information from the manual to the INSTALL file.
+
+Version 1.7.0beta35 [August 6, 2014]
+  Removed #if/#else/#endif from inside two pow() calls in pngvalid.c because
+    they were handled improperly by Portland Group's PGI-14.1 - PGI-14.3
+    when using its "__builtin_pow()" function.
+  Silence 'unused parameter' build warnings (Cosmin).
+  $(CP) is now used alongside $(RM_F).  Also, use 'copy' instead
+    of 'cp' where applicable, and applied other minor makefile changes.
+  Don't warn about invalid dimensions exceeding user limits.
+  Allow an easy replacement of the default pre-built configuration
+    header with a custom header, via the make PNGLIBCONF_H_PREBUILT
+    macro.
+  Fixed a typo in pngrutil.c, introduced in libpng-1.5.6, that interferes
+    with "blocky" expansion of sub-8-bit interlaced PNG files (Eric Huss).
+  Removed scripts/makefile.elf. It has not worked since libpng-1.5.0beta14
+    due to elimination of the PNG_FUNCTION_EXPORT and PNG_DATA_EXPORT
+    definitions from pngconf.h.
+  Ensure that CMakeLists.txt makes the target "lib" directory before making
+    symbolic link into it (SourceForge bug report #226 by Rolf Timmermans).
+  Added opinion that the ECCN (Export Control Classification Number) for
+    libpng is EAR99 to the README file.
+
+Version 1.7.0beta36 [September 27, 2014]
+  Updated scripts/makefiles from libpng-1.6.13beta04.
+  Minor updates to the manual from libpng-1.6.14beta04.
+  Fixed incorrect handling of the iTXt compression flag in pngrutil.c
+    (bug report by Shunsaku Hirata).  Bug was introduced in libpng-1.6.0.
+
+Version 1.7.0beta37 [September 28, 2014]
+  Merged scripts/*, pngvalid.c and pngfix.c with libpng-1.6.14beta04.
+
+Version 1.7.0beta38 [October 17, 2014]
+  Added "option READ_iCCP enables READ_COMPRESSED_TEXT" to pnglibconf.dfa
+  Removed unused "text_len" parameter from private function png_write_zTXt().
+  Conditionally compile some code in png_deflate_claim(), when
+    PNG_WARNINGS_SUPPORTED and PNG_ERROR_TEXT_SUPPORTED are disabled.
+  Replaced repeated code in pngpread.c with PNG_PUSH_SAVE_BUFFER_IF_FULL.
+  Added "chunk iTXt enables TEXT" and "chunk zTXt enables TEXT"
+    to pnglibconf.dfa.
+  Removed "option READ_COMPRESSED_TEXT enables READ_TEXT" from pnglibconf.dfa,
+    to make it possible to configure a libpng that supports iCCP but not TEXT.
+  Removed "option WRITE_COMPRESSED_TEXT enables WRITE_TEXT" from pnglibconf.dfa
+  Only mark text chunks as written after successfully writing them.
+
+Version 1.7.0beta39 [November 1, 2014]
+  Ported cosmetic changes from libpng-1.6.15beta02.
+
+Version 1.7.0beta40 [November 6, 2014]
+  Made a one-line revision to configure.ac to support ARM on aarch64
+    (bug report by Marcin Juszkiewicz, fix by John Bowler).
+  Use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING in
+    example.c, pngtest.c, and applications in the contrib directory.
+  Avoid out-of-bounds memory access in png_user_version_check().
+  Simplified and future-proofed png_user_version_check().
+  Fixed GCC unsigned int->float warnings. Various versions of GCC
+    seem to generate warnings when an unsigned value is implicitly
+    converted to double. This is probably a GCC bug but this change
+    avoids the issue by explicitly converting to (int) where safe.
+  Free all allocated memory in pngimage. The file buffer cache was left
+    allocated at the end of the program, harmless but it causes memory
+    leak reports from clang.
+  Fixed array size calculations to avoid warnings. At various points
+    in the code the number of elements in an array is calculated using
+    sizeof.  This generates a compile time constant of type (size_t) which
+    is then typically assigned to an (unsigned int) or (int). Some versions
+    of GCC on 64-bit systems warn about the apparent narrowing, even though
+    the same compiler does apparently generate the correct, in-range,
+    numeric constant.  This adds appropriate, safe, casts to make the
+    warnings go away.
+
+Version 1.7.0beta41 [November 7, 2014]
+  Added #ifdef PNG_16BIT_SUPPORTED/#endif around png_log16bit() and
+    png_do_swap().
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CMakeLists.txt

@@ -1,6 +1,6 @@
 # CMakeLists.txt
 
-# Copyright (C) 2007-2011 Glenn Randers-Pehrson
+# Copyright (C) 2007-2014 Glenn Randers-Pehrson
 
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -9,26 +9,7 @@
 cmake_minimum_required(VERSION 2.4.4)
 set(CMAKE_ALLOW_LOOSE_LOOP_CONSTRUCTS true)
 
-if(UNIX AND NOT DEFINED CMAKE_BUILD_TYPE)
-  if(CMAKE_MAJOR_VERSION EQUAL 2 AND CMAKE_MINOR_VERSION EQUAL 4)
-    # workaround CMake 2.4.x bug
-    set(CMAKE_BUILD_TYPE "RelWithDebInfo" CACHE STRING
-        "Choose the type of build, options are:
-           None(CMAKE_CXX_FLAGS or CMAKE_C_FLAGS used)
-           Debug
-           Release
-           RelWithDebInfo
-           MinSizeRel.")
-  else()
-    set(CMAKE_BUILD_TYPE "RelWithDebInfo" CACHE STRING
-        "Choose the type of build, options are:
-           None(CMAKE_CXX_FLAGS or CMAKE_C_FLAGS used)
-           Debug
-           Release
-           RelWithDebInfo
-           MinSizeRel.")
-  endif()
-endif()
+set(CMAKE_CONFIGURATION_TYPES "Release;Debug;MinSizeRel;RelWithDebInfo")
 
 project(libpng C)
 enable_testing()
@@ -239,6 +220,7 @@ macro(CREATE_SYMLINK SRC_FILE DEST_FILE)
     ADD_CUSTOM_TARGET(${DEST_FILE}_COPY ALL DEPENDS ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE})
   else(WIN32 AND NOT CYGWIN AND NOT MSYS)
     get_filename_component(LINK_TARGET "${SRC_FILE}" NAME)
+    execute_process(COMMAND ${CMAKE_COMMAND} -E make_directory ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_LIBRARY_OUTPUT_DIRECTORY})
     execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${CMAKE_LIBRARY_OUTPUT_DIRECTORY}/${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
     execute_process(COMMAND ${CMAKE_COMMAND} -E create_symlink "${LINK_TARGET}" ${DEST_FILE} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
   endif(WIN32 AND NOT CYGWIN AND NOT MSYS)
@@ -271,7 +253,7 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)
 # SET UP LINKS
 if(PNG_SHARED)
   set_target_properties(${PNG_LIB_NAME} PROPERTIES
-#   VERSION 17.${PNGLIB_RELEASE}.1.7.0beta08
+#   VERSION 17.${PNGLIB_RELEASE}.1.7.0beta41
     VERSION 17.${PNGLIB_RELEASE}.0
     SOVERSION 17
     CLEAN_DIRECT_OUTPUT 1)
@@ -369,7 +351,7 @@ if(PNG_EXPORT_RULE AND NOT SKIP_INSTALL_EXPORT AND NOT SKIP_INSTALL_ALL )
   install(EXPORT libpng DESTINATION lib/libpng FILE lib${PNG_LIB_NAME}.cmake)
 endif()
 
-# what's with libpng-$VER%.txt and all the extra files?
+# what's with libpng-manual.txt and all the extra files?
 
 # UNINSTALL
 # do we need this?

INSTALL

@@ -1,13 +1,47 @@
 
 Installing libpng
 
+Contents
+
+   I. Simple installation
+  II. Rebuilding the configure scripts
+ III. Using scripts/makefile*
+  IV. Using cmake
+   V. Directory structure
+  VI. Building with project files
+ VII. Building with makefiles
+VIII. Configuring libpng for 16-bit platforms
+  IX. Configuring for DOS
+   X. Configuring for Medium Model
+  XI. Prepending a prefix to exported symbols
+ XII. Configuring for compiler xxx:
+XIII. Removing unwanted object code
+ XIV. Changes to the build and configuration of libpng in libpng-1.5.x
+  XV. Configuring libpng for multiprocessing
+ XVI. Other sources of information about libpng
+
+I. Simple installation
+
 On Unix/Linux and similar systems, you can simply type
 
     ./configure [--prefix=/path]
     make check
     make install
 
-and ignore the rest of this document.
+and ignore the rest of this document.  "/path" is the path to the directory
+where you want to install the libpng "lib", "include", and "bin"
+subdirectories.
+
+If you downloaded a GIT clone, you will need to run ./autogen.sh before
+running ./configure, to create "configure" and "Makefile.in" which are
+not included in the GIT repository.
+
+Note that "configure" is only included in the "*.tar" distributions and not
+in the "*.zip" or "*.7z" distributions. If you downloaded one of those
+distributions, see "Building with project files" or "Building with makefiles",
+below.
+
+II. Rebuilding the configure scripts
 
 If configure does not work on your system, or if you have a need to
 change configure.ac or Makefile.am, and you have a reasonably
@@ -24,9 +58,12 @@ aren't using any of the included pre-built scripts, you can do this:
     make install
     make check
 
+III. Using scripts/makefile*
+
 Instead, you can use one of the custom-built makefiles in the
 "scripts" directory
 
+    cp scripts/pnglibconf.h.prebuilt pnglibconf.h
     cp scripts/makefile.system makefile
     make test
     make install
@@ -38,8 +75,8 @@ Or you can use one of the "projects" in the "projects" directory.
 
 Before installing libpng, you must first install zlib, if it
 is not already on your system.  zlib can usually be found
-wherever you got libpng.  zlib can be placed in another directory,
-at the same level as libpng.
+wherever you got libpng; otherwise go to http://zlib.net.  You can place
+zlib in in the same directory as libpng or in another directory.
 
 If your system already has a preinstalled zlib you will still need
 to have access to the zlib.h and zconf.h include files that
@@ -59,15 +96,23 @@ LD_LIBRARY_PATH="$ZLIBLIB:$LD_LIBRARY_PATH" export LD_LIBRARY_PATH
 If you are using one of the makefile scripts, put ZLIBLIB and ZLIBINC
 in your environment and type "make ZLIBLIB=$ZLIBLIB ZLIBINC=$ZLIBINC test".
 
+IV. Using cmake
+
 If you want to use "cmake" (see www.cmake.org), type
 
    cmake . -DCMAKE_INSTALL_PREFIX=/path
    make
    make install
 
+As when using the simple configure method described above, "/path" points to
+the installation directory where you want to put the libpng "lib", "include",
+and "bin" subdirectories.
+
+V. Directory structure
+
 You can rename the directories that you downloaded (they
-might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.7"
-or "zlib127") so that you have directories called "zlib" and "libpng".
+might be called "libpng-x.y.z" or "libpngNN" and "zlib-1.2.8"
+or "zlib128") so that you have directories called "zlib" and "libpng".
 
 Your directory structure should look like this:
 
@@ -75,8 +120,7 @@ Your directory structure should look like this:
       libpng  (this directory)
           INSTALL (this file)
           README
-          *.h
-          *.c
+          *.h, *.c  => libpng source files
           CMakeLists.txt    =>  "cmake" script
           configuration files:
              configure.ac, configure, Makefile.am, Makefile.in,
@@ -84,15 +128,10 @@ Your directory structure should look like this:
              libpng-config.in, aclocal.m4, config.h.in, config.sub,
              depcomp, install-sh, mkinstalldirs, test-pngtest.sh
           contrib
-             gregbook
-             libtests
-             pngminim
-             pngminus
-             pngsuite
-             visupng
+             arm-neon, conftest, examples, gregbook, libtests, pngminim,
+             pngminus, pngsuite, tools, visupng
           projects
-             visualc71
-             vstudio
+             cbuilder5, owatcom, visualc71, vstudio, xcode
           scripts
              makefile.*
              *.def (module definition files)
@@ -100,29 +139,31 @@ Your directory structure should look like this:
           pngtest.png
           etc.
       zlib
-          README
-          *.h
-          *.c
-          contrib
-          etc.
+          README, *.h, *.c contrib, etc.
 
 If the line endings in the files look funny, you may wish to get the other
 distribution of libpng.  It is available in both tar.gz (UNIX style line
 endings) and zip (DOS style line endings) formats.
 
+VI. Building with project files
+
 If you are building libpng with MSVC, you can enter the
-libpng projects\visualc6 or visualc71 directory and follow the instructions
+libpng projects\visualc71 or vstudio directory and follow the instructions
 in README.txt.
 
 Otherwise enter the zlib directory and follow the instructions in zlib/README,
 then come back here and run "configure" or choose the appropriate
 makefile.sys in the scripts directory.
 
+VII. Building with makefiles
+
 Copy the file (or files) that you need from the
 scripts directory into this directory, for example
 
    MSDOS example: copy scripts\makefile.msc makefile
-   UNIX example:    cp scripts/makefile.std makefile
+                  copy scripts\pnglibconf.h.prebuilt pnglibconf.h
+   UNIX example:  cp scripts/makefile.std makefile
+                  cp scripts/pnglibconf.h.prebuilt pnglibconf.h
 
 Read the makefile to see if you need to change any source or
 target directories to match your preferences.
@@ -145,6 +186,197 @@ do that, run "make install" in the zlib directory first if necessary).
 Some also allow you to run "make test-installed" after you have
 run "make install".
 
+VIII. Configuring libpng for 16-bit platforms
+
+You will want to look into zconf.h to tell zlib (and thus libpng) that
+it cannot allocate more then 64K at a time.  Even if you can, the memory
+won't be accessible.  So limit zlib and libpng to 64K by defining MAXSEG_64K.
+
+IX. Configuring for DOS
+
+For DOS users who only have access to the lower 640K, you will
+have to limit zlib's memory usage via a png_set_compression_mem_level()
+call.  See zlib.h or zconf.h in the zlib library for more information.
+
+X. Configuring for Medium Model
+
+Libpng's support for medium model has been tested on most of the popular
+compilers.  Make sure MAXSEG_64K gets defined, USE_FAR_KEYWORD gets
+defined, and FAR gets defined to far in pngconf.h, and you should be
+all set.  Everything in the library (except for zlib's structure) is
+expecting far data.  You must use the typedefs with the p or pp on
+the end for pointers (or at least look at them and be careful).  Make
+note that the rows of data are defined as png_bytepp, which is
+an "unsigned char far * far *".
+
+XI. Prepending a prefix to exported symbols
+
+Starting with libpng-1.6.0, you can configure libpng (when using the
+"configure" script) to prefix all exported symbols by means of the
+configuration option "--with-libpng-prefix=FOO_", where FOO_ can be any
+string beginning with a letter and containing only uppercase
+and lowercase letters, digits, and the underscore (i.e., a C language
+identifier).  This creates a set of macros in pnglibconf.h, so this is
+transparent to applications; their function calls get transformed by
+the macros to use the modified names.
+
+XII. Configuring for compiler xxx:
+
+All includes for libpng are in pngconf.h.  If you need to add, change
+or delete an include, this is the place to do it.
+The includes that are not needed outside libpng are placed in pngpriv.h,
+which is only used by the routines inside libpng itself.
+The files in libpng proper only include pngpriv.h and png.h, which
+in turn includes pngconf.h and, as of libpng-1.5.0, pnglibconf.h.
+As of libpng-1.5.0, pngpriv.h also includes three other private header
+files, pngstruct.h, pnginfo.h, and pngdebug.h, which contain material
+that previously appeared in the public headers.
+
+XIII. Removing unwanted object code
+
+There are a bunch of #define's in pngconf.h that control what parts of
+libpng are compiled.  All the defines end in _SUPPORTED.  If you are
+never going to use a capability, you can change the #define to #undef
+before recompiling libpng and save yourself code and data space, or
+you can turn off individual capabilities with defines that begin with
+PNG_NO_.
+
+In libpng-1.5.0 and later, the #define's are in pnglibconf.h instead.
+
+You can also turn all of the transforms and ancillary chunk capabilities
+off en masse with compiler directives that define
+PNG_NO_READ[or WRITE]_TRANSFORMS, or PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS,
+or all four, along with directives to turn on any of the capabilities that
+you do want.  The PNG_NO_READ[or WRITE]_TRANSFORMS directives disable the
+extra transformations but still leave the library fully capable of reading
+and writing PNG files with all known public chunks. Use of the
+PNG_NO_READ[or WRITE]_ANCILLARY_CHUNKS directive produces a library
+that is incapable of reading or writing ancillary chunks.  If you are
+not using the progressive reading capability, you can turn that off
+with PNG_NO_PROGRESSIVE_READ (don't confuse this with the INTERLACING
+capability, which you'll still have).
+
+All the reading and writing specific code are in separate files, so the
+linker should only grab the files it needs.  However, if you want to
+make sure, or if you are building a stand alone library, all the
+reading files start with "pngr" and all the writing files start with "pngw".
+The files that don't match either (like png.c, pngtrans.c, etc.)
+are used for both reading and writing, and always need to be included.
+The progressive reader is in pngpread.c
+
+If you are creating or distributing a dynamically linked library (a .so
+or DLL file), you should not remove or disable any parts of the library,
+as this will cause applications linked with different versions of the
+library to fail if they call functions not available in your library.
+The size of the library itself should not be an issue, because only
+those sections that are actually used will be loaded into memory.
+
+XIV. Changes to the build and configuration of libpng in libpng-1.5.x
+
+Details of internal changes to the library code can be found in the CHANGES
+file and in the GIT repository logs.  These will be of no concern to the vast
+majority of library users or builders; however, the few who configure libpng
+to a non-default feature set may need to change how this is done.
+
+There should be no need for library builders to alter build scripts if
+these use the distributed build support - configure or the makefiles -
+however, users of the makefiles may care to update their build scripts
+to build pnglibconf.h where the corresponding makefile does not do so.
+
+Building libpng with a non-default configuration has changed completely.
+The old method using pngusr.h should still work correctly even though the
+way pngusr.h is used in the build has been changed; however, library
+builders will probably want to examine the changes to take advantage of
+new capabilities and to simplify their build system.
+
+A. Specific changes to library configuration capabilities
+
+The exact mechanism used to control attributes of API functions has
+changed.  A single set of operating system independent macro definitions
+is used and operating system specific directives are defined in
+pnglibconf.h
+
+As part of this the mechanism used to choose procedure call standards on
+those systems that allow a choice has been changed.  At present this only
+affects certain Microsoft (DOS, Windows) and IBM (OS/2) operating systems
+running on Intel processors.  As before, PNGAPI is defined where required
+to control the exported API functions; however, two new macros, PNGCBAPI
+and PNGCAPI, are used instead for callback functions (PNGCBAPI) and
+(PNGCAPI) for functions that must match a C library prototype (currently
+only png_longjmp_ptr, which must match the C longjmp function.)  The new
+approach is documented in pngconf.h
+
+Despite these changes, libpng 1.5.0 only supports the native C function
+calling standard on those platforms tested so far (__cdecl on Microsoft
+Windows).  This is because the support requirements for alternative
+calling conventions seem to no longer exist.  Developers who find it
+necessary to set PNG_API_RULE to 1 should advise the mailing list
+(png-mng-implement) of this and library builders who use Openwatcom and
+therefore set PNG_API_RULE to 2 should also contact the mailing list.
+
+B. Changes to the configuration mechanism
+
+Prior to libpng-1.5.0 library builders who needed to configure libpng
+had either to modify the exported pngconf.h header file to add system
+specific configuration or had to write feature selection macros into
+pngusr.h and cause this to be included into pngconf.h by defining
+PNG_USER_CONFIG. The latter mechanism had the disadvantage that an
+application built without PNG_USER_CONFIG defined would see the
+unmodified, default, libpng API and thus would probably fail to link.
+
+These mechanisms still work in the configure build and in any makefile
+build that builds pnglibconf.h, although the feature selection macros
+have changed somewhat as described above.  In 1.5.0, however, pngusr.h is
+processed only once, at the time the exported header file pnglibconf.h is
+built.  pngconf.h no longer includes pngusr.h; therefore, pngusr.h is ignored
+after the build of pnglibconf.h and it is never included in an application
+build.
+
+The formerly used alternative of adding a list of feature macros to the
+CPPFLAGS setting in the build also still works; however, the macros will be
+copied to pnglibconf.h and this may produce macro redefinition warnings
+when the individual C files are compiled.
+
+All configuration now only works if pnglibconf.h is built from
+scripts/pnglibconf.dfa.  This requires the program awk.  Brian Kernighan
+(the original author of awk) maintains C source code of that awk and this
+and all known later implementations (often called by subtly different
+names - nawk and gawk for example) are adequate to build pnglibconf.h.
+The Sun Microsystems (now Oracle) program 'awk' is an earlier version
+and does not work; this may also apply to other systems that have a
+functioning awk called 'nawk'.
+
+Configuration options are now documented in scripts/pnglibconf.dfa.  This
+file also includes dependency information that ensures a configuration is
+consistent; that is, if a feature is switched off, dependent features are
+also switched off.  As a recommended alternative to using feature macros in
+pngusr.h a system builder may also define equivalent options in pngusr.dfa
+(or, indeed, any file) and add that to the configuration by setting
+DFA_XTRA to the file name.  The makefiles in contrib/pngminim illustrate
+how to do this, and also illustrate a case where pngusr.h is still required.
+
+After you have built libpng, the definitions that were recorded in
+pnglibconf.h are available to your application (pnglibconf.h is included
+in png.h and gets installed alongside png.h and pngconf.h in your
+$PREFIX/include directory).  Do not edit pnglibconf.h after you have built
+libpng, because than the settings would not accurately reflect the settings
+that were used to build libpng.
+
+XV. Configuring libpng for multiprocessing
+
+Libpng uses setjmp()/longjmp() for error handling.  Unfortunately setjmp()
+is known to be not thread-safe on some platforms and we don't know of
+any platform where it is guaranteed to be thread-safe.  Therefore, if
+your application is going to be using multiple threads, you should
+configure libpng with PNG_NO_SETJMP in your pngusr.dfa file, with
+-DPNG_NO_SETJMP on your compile line, or with
+
+  #undef PNG_SETJMP_SUPPORTED
+
+in your pnglibconf.h or pngusr.h.
+
+XVI. Other sources of information about libpng:
+
 Further information can be found in the README and libpng-manual.txt
 files, in the individual makefiles, in png.h, and the manual pages
 libpng.3 and png.5.
@@ -162,7 +394,7 @@ CFLAGS="-Wall -O -funroll-loops \
 --with-pkgconfigdir=/usr/lib/pkgconfig --includedir=/usr/include
 
 You can alternatively specify --includedir=/usr/include, /usr/local/include,
-/usr/include/libpng%NN%, or whatever.
+/usr/include/libpng17, or whatever.
 
 If you find that the configure script is out-of-date or is not supporting
 your platform properly, try running autogen.sh to regenerate "configure",

LICENSE

@@ -10,8 +10,8 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.2.6, August 15, 2004, through 1.7.0beta08, April 14, 2013, are
-Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are
+libpng versions 1.2.6, August 15, 2004, through 1.7.0beta41, November 7, 2014, are
+Copyright (c) 2004, 2006-2014 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
 
@@ -108,4 +108,4 @@ certification mark of the Open Source Initiative.
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-April 14, 2013
+November 7, 2014

Makefile.am

@@ -7,7 +7,20 @@ PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
 ACLOCAL_AMFLAGS = -I scripts
 
 # test programs - run on make check, make distcheck
-check_PROGRAMS= pngtest pngunknown pngstest pngvalid
+check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage
+
+# Utilities - installed
+bin_PROGRAMS= pngfix png-fix-itxt
+
+# This ensures that pnglibconf.h gets built at the start of 'make all' or
+# 'make check', but it does not add dependencies to the individual programs,
+# this is done below.
+#
+# IMPORTANT: always add the object modules of new programs to the list below
+# because otherwise the sequence 'configure; make new-program' will *sometimes*
+# result in the installed (system) pnglibconf.h being used and the result is
+# always wrong and always very confusing.
+BUILT_SOURCES = pnglibconf.h
 
 pngtest_SOURCES = pngtest.c
 pngtest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
@@ -21,6 +34,14 @@ pngstest_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 pngunknown_SOURCES = contrib/libtests/pngunknown.c
 pngunknown_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 
+pngimage_SOURCES = contrib/libtests/pngimage.c
+pngimage_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+pngfix_SOURCES = contrib/tools/pngfix.c
+pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
+png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
+
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
 TESTS =\
@@ -41,7 +62,8 @@ TESTS =\
    tests/pngstest-4a16 tests/pngstest-6a08 tests/pngstest-6a16\
    tests/pngstest-error tests/pngunknown-IDAT\
    tests/pngunknown-discard tests/pngunknown-if-safe tests/pngunknown-sAPI\
-   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg
+   tests/pngunknown-sTER tests/pngunknown-save tests/pngunknown-vpAg\
+   tests/pngimage-quick tests/pngimage-full
 
 # These tests are expected, and required, to fail:
 XFAIL_TESTS = tests/pngstest-error
@@ -64,7 +86,7 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = png.c pngerror.c\
 
 if PNG_ARM_NEON
 libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += arm/arm_init.c\
-	arm/filter_neon.S
+	arm/filter_neon.S arm/filter_neon_intrinsics.c
 endif
 
 nodist_libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES = pnglibconf.h
@@ -123,8 +145,8 @@ config.sub configure depcomp install-sh ltmain.sh missing
 PNG_COPTS = @PNG_COPTS@
 AM_CFLAGS = ${PNG_COPTS}
 
-# DFNCPP is normally just CPP - the C preprocessor - but on Solaris and maybe
-# other operating systems (NeXT?) the C preprocessor selected by configure
+# DFNCPP is normally just "CPP -E" - the C preprocessor - but on Solaris and
+# maybe other operating systems (NeXT?) the C preprocessor selected by configure
 # checks input tokens for validity - effectively it performs part of the ANSI-C
 # parsing - and therefore fails with the .df files.  configure.ac has special
 # checks for this and sets DFNCPP appropriately.
@@ -182,14 +204,28 @@ endif
 $(srcdir)/scripts/pnglibconf.h.prebuilt:
 	@echo "Attempting to build $@" >&2
 	@echo "This is a machine generated file, but if you want to make" >&2
-	@echo "a new one simply make 'scripts/pnglibconf.out' and copy that" >&2
+	@echo "a new one simply make 'scripts/pnglibconf.out', copy that" >&2
+	@echo "AND set PNG_ZLIB_VERNUM to 0 (you MUST do this)" >&2
 	@exit 1
 
 # The following is necessary to ensure that the local pnglibconf.h is used, not
 # an installed one (this can happen immediately after on a clean system if
-# 'make test' is the first thing the user does.)
-contrib/libtests/pngstest.o contrib/libtests/pngvalid.o pngtest.o: pnglibconf.h
+# 'make test' is the first thing the user does.)  Only files which include
+# one of the png source files (typically png.h or pngpriv.h) need to be listed
+# here:
+pngtest.o: pnglibconf.h
+
+contrib/libtests/makepng.o: pnglibconf.h
+contrib/libtests/pngstest.o: pnglibconf.h
 contrib/libtests/pngunknown.o: pnglibconf.h
+contrib/libtests/pngimage.o: pnglibconf.h
+contrib/libtests/pngvalid.o: pnglibconf.h
+contrib/libtests/readpng.o: pnglibconf.h
+contrib/libtests/tarith.o: pnglibconf.h
+contrib/libtests/timepng.o: pnglibconf.h
+
+contrib/tools/makesRGB.o: pnglibconf.h
+contrib/tools/pngfix.o: pnglibconf.h
 
 # We must use -DPNG_NO_USE_READ_MACROS here even when the library may actually
 # be built with PNG_USE_READ_MACROS; this prevents the read macros from
@@ -258,40 +294,76 @@ check: scripts/symbols.chk
 dist-hook:
 	cd '$(top_distdir)'; rm -f $(SCRIPT_CLEANFILES)
 
-# install the .../include headers as links to the new ones
-install-data-hook:
-	cd '$(DESTDIR)$(includedir)'; rm -f png.h pngconf.h pnglibconf.h
-	cd '$(DESTDIR)$(includedir)'; $(LN_S) $(PNGLIB_BASENAME)/png.h png.h
-	cd '$(DESTDIR)$(includedir)'; $(LN_S) $(PNGLIB_BASENAME)/pngconf.h \
-		pngconf.h
-	cd '$(DESTDIR)$(includedir)'; $(LN_S) $(PNGLIB_BASENAME)/pnglibconf.h \
-		pnglibconf.h
-	cd '$(DESTDIR)$(pkgconfigdir)'; rm -f libpng.pc
-	cd '$(DESTDIR)$(pkgconfigdir)'; $(LN_S) $(PNGLIB_BASENAME).pc libpng.pc
+# Make links between installed files with release-specific names and the generic
+# file names.  If this install rule is run the generic names will be deleted and
+# recreated - this has obvious issues for systems with multiple installations.
 
-# do evil things to libpng to cause libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@ to be used
-install-exec-hook:
-	cd '$(DESTDIR)$(bindir)'; rm -f libpng-config
-	cd '$(DESTDIR)$(bindir)';\
-	   $(LN_S) $(PNGLIB_BASENAME)-config libpng-config
-	@set -x;\
-	cd '$(DESTDIR)$(libdir)';\
-	for ext in a la so so.@PNGLIB_MAJOR@@PNGLIB_MINOR@.@PNGLIB_RELEASE@\
-	   sl dylib dll.a; do\
-		rm -f libpng.$$ext;\
-                if test -f $(PNGLIB_BASENAME).$$ext; then\
-                       $(LN_S) $(PNGLIB_BASENAME).$$ext libpng.$$ext;\
-                fi;\
+install-header-links:
+	@set -ex; cd '$(DESTDIR)$(includedir)'; for f in $(HEADERS); do \
+	   rm -f "$$f"; $(LN_S) "$(PNGLIB_BASENAME)/$$f" "$$f"; done
+
+uninstall-header-links:
+	cd '$(DESTDIR)$(includedir)'; rm -f $(HEADERS)
+
+install-libpng-pc:
+	@set -ex; cd '$(DESTDIR)$(pkgconfigdir)'; rm -f libpng.pc; \
+	   $(LN_S) '$(PNGLIB_BASENAME).pc' libpng.pc
+
+uninstall-libpng-pc:
+	rm -f '$(DESTDIR)$(pkgconfigdir)/libpng.pc'
+
+# EXT_LIST is a list of the possibly library directory extensions, this exists
+# because we can't find a good way of discovering the file extensions that are
+# actually installed on a given system, so instead we check for every extension
+# we have seen.
+
+EXT_LIST = a dll.a so so.@PNGLIB_MAJOR@@PNGLIB_MINOR@.@PNGLIB_RELEASE@ la sl dylib
+
+install-library-links:
+	@set -x; cd '$(DESTDIR)$(libdir)';\
+	for ext in $(EXT_LIST); do\
+	   rm -f "libpng.$$ext";\
+           if test -f "$(PNGLIB_BASENAME).$$ext"; then\
+              $(LN_S) "$(PNGLIB_BASENAME).$$ext" "libpng.$$ext" || exit 1;\
+           fi;\
 	done
 
-uninstall-hook:
-	cd '$(DESTDIR)$(includedir)'; rm -f png.h pngconf.h pnglibconf.h
-	rm -f '$(DESTDIR)$(pkgconfigdir)/libpng.pc'
+uninstall-library-links:
+	@set -x; cd '$(DESTDIR)$(libdir)'; for ext in $(EXT_LIST); do\
+	   rm -f "libpng.$$ext"; done
+
+install-libpng-config:
+	@set -ex; cd '$(DESTDIR)$(bindir)'; rm -f libpng-config; \
+	   $(LN_S) '$(PNGLIB_BASENAME)-config' libpng-config
+
+uninstall-libpng-config:
 	rm -f '$(DESTDIR)$(bindir)/libpng-config'
-	rm -f '$(DESTDIR)$(libdir)/libpng.a'
-	rm -f '$(DESTDIR)$(libdir)/libpng.la'
-	rm -f '$(DESTDIR)$(libdir)/libpng.so'
-	rm -f '$(DESTDIR)$(libdir)/libpng.so.@PNGLIB_MAJOR@@PNGLIB_MINOR@.@PNGLIB_RELEASE@'
-	rm -f '$(DESTDIR)$(libdir)/libpng.sl'
-	rm -f '$(DESTDIR)$(libdir)/libpng.dylib'
-	rm -f '$(DESTDIR)$(libdir)/libpng.dll.a'
+
+if DO_INSTALL_LINKS
+# If --enable-unversioned-links is specified the header and lib file links
+# will be automatically made on a 'make install':
+
+install-data-hook: install-header-links
+uninstall-hook: uninstall-header-links
+install-exec-hook: install-library-links
+uninstall-hook: uninstall-library-links
+endif
+
+if DO_INSTALL_LIBPNG_PC
+# Likewise, --install-pc causes libpng.pc to be constructed:
+
+install-data-hook: install-libpng-pc
+uninstall-hook: uninstall-libpng-pc
+endif
+
+if DO_INSTALL_LIBPNG_CONFIG
+# And --install-config:
+
+install-exec-hook: install-libpng-config
+uninstall-hook: uninstall-libpng-config
+endif
+
+# The following addition ensures that 'make all' always builds the test programs
+# too.  It used to, but some change either in libpng or configure stopped this
+# working.
+all-am: $(check_PROGRAMS)

README

@@ -1,11 +1,11 @@
-README for libpng version 1.7.0beta08 - April 14, 2013 (shared library 17.0)
+README for libpng version 1.7.0beta41 - November 7, 2014 (shared library 17.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
 
-Libpng comes in several distribution formats.  Get libpng-*.tar.gz,
-libpng-*.tar.xz or libpng-*.tar.bz2 if you want UNIX-style line endings
-in the text files, or lpng*.zip if you want DOS-style line endings.
+Libpng comes in several distribution formats.  Get libpng-*.tar.gz or
+libpng-*.tar.xz or if you want UNIX-style line endings in the text files,
+or lpng*.7z or lpng*.zip if you want DOS-style line endings.
 
 Version 0.89 was the first official release of libpng.  Don't let the
 fact that it's the first release fool you.  The libpng library has been in
@@ -23,18 +23,25 @@ earlier versions if you are using a shared library.  The type of the
 png_uint_32, which will affect shared-library applications that use
 this function.
 
-To avoid problems with changes to the internals of png_info_struct,
+To avoid problems with changes to the internals of png info_struct,
 new APIs have been made available in 0.95 to avoid direct application
 access to info_ptr.  These functions are the png_set_<chunk> and
 png_get_<chunk> functions.  These functions should be used when
 accessing/storing the info_struct data, rather than manipulating it
 directly, to avoid such problems in the future.
 
-It is important to note that the APIs do not make current programs
+It is important to note that the APIs did not make current programs
 that access the info struct directly incompatible with the new
-library.  However, it is strongly suggested that new programs use
-the new APIs (as shown in example.c and pngtest.c), and older programs
-be converted to the new format, to facilitate upgrades in the future.
+library, through libpng-1.2.x.  In libpng-1.4.x, which was meant to
+be a transitional release, members of the png_struct and the
+info_struct can still be accessed, but the compiler will issue a
+warning about deprecated usage.  Since libpng-1.5.0, direct access
+to these structs is not allowed, and the definitions of the structs
+reside in private pngstruct.h and pnginfo.h header files that are not
+accessible to applications.  It is strongly suggested that new
+programs use the new APIs (as shown in example.c and pngtest.c), and
+older programs be converted to the new format, to facilitate upgrades
+in the future.
 ****
 
 Additions since 0.90 include the ability to compile libpng as a
@@ -77,17 +84,21 @@ compression library that is useful for more things than just PNG files.
 You can use zlib as a drop-in replacement for fread() and fwrite() if
 you are so inclined.
 
-zlib should be available at the same place that libpng is, or at.
-ftp://ftp.info-zip.org/pub/infozip/zlib
+zlib should be available at the same place that libpng is, or at zlib.net.
 
 You may also want a copy of the PNG specification.  It is available
 as an RFC, a W3C Recommendation, and an ISO/IEC Standard.  You can find
 these at http://www.libpng.org/pub/png/documents/
 
 This code is currently being archived at libpng.sf.net in the
-[DOWNLOAD] area, and on CompuServe, Lib 20 (PNG SUPPORT)
-at GO GRAPHSUP.  If you can't find it in any of those places,
-e-mail me, and I'll help you find it.
+[DOWNLOAD] area, and at ftp://ftp.simplesystems.org.  If you can't find it
+in any of those places, e-mail me, and I'll help you find it.
+
+I am not a lawyer, but I believe that the Export Control Classification
+Number (ECCN) for libpng is EAR99, which means not subject to export
+controls or International Traffic in Arms Regulations (ITAR) because it
+is open source, publicly available software, that does not contain any
+encryption software.  See the EAR, paragraphs 734.3(b)(3) and 734.7(b).
 
 If you have any code changes, requests, problems, etc., please e-mail
 them to me.  Also, I'd appreciate any make files or project files,
@@ -123,7 +134,7 @@ and ...".  If in doubt, send questions to me.  I'll bounce them
 to others, if necessary.
 
 Please do not send suggestions on how to change PNG.  We have
-been discussing PNG for sixteen years now, and it is official and
+been discussing PNG for nineteen years now, and it is official and
 finished.  If you have suggestions for libpng, however, I'll
 gladly listen.  Even if your suggestion is not used immediately,
 it may be used later.
@@ -167,23 +178,25 @@ Files in this distribution:
       pngwrite.c    =>  High-level write functions
       pngwtran.c    =>  Write data transformations
       pngwutil.c    =>  Write utility functions
+      arm           =>  Contains optimized code for the ARM platform
       contrib       =>  Contributions
+       examples         =>  Example programs
        gregbook         =>  source code for PNG reading and writing, from
                             Greg Roelofs' "PNG: The Definitive Guide",
                             O'Reilly, 1999
-       msvctest     =>  Builds and runs pngtest using a MSVC workspace
-       pngminus     =>  Simple pnm2png and png2pnm programs
-       pngsuite     =>  Test images
-       visupng      =>  Contains a MSVC workspace for VisualPng
+       libtests         =>  Test programs
+       pngminim         =>  Minimal decoder, encoder, and progressive decoder
+                            programs demonstrating use of pngusr.dfa
+       pngminus         =>  Simple pnm2png and png2pnm programs
+       pngsuite         =>  Test images
+       tools            =>  Various tools
+       visupng          =>  Contains a MSVC workspace for VisualPng
       projects      =>  Contains project files and workspaces for
                         building a DLL
-       cbuilder5        =>  Contains a Borland workspace for building
-                            libpng and zlib
-       visualc6         =>  Contains a Microsoft Visual C++ (MSVC)
-                            workspace for building libpng and zlib
+       owatcom          =>  Contains a WATCOM project for building libpng
        visualc71        =>  Contains a Microsoft Visual C++ (MSVC)
                             workspace for building libpng and zlib
-       xcode            =>  Contains an Apple xcode
+       vstudio          =>  Contains a Microsoft Visual C++ (MSVC)
                             workspace for building libpng and zlib
       scripts       =>  Directory containing scripts for building libpng:
                             (see scripts/README.txt for the list of scripts)

TODO

@@ -6,10 +6,12 @@ Better C++ wrapper/full C++ implementation?
 Fix problem with C++ and EXTERN "C".
 cHRM transformation.
 Remove setjmp/longjmp usage in favor of returning error codes.
+Palette creation.
 Add "grayscale->palette" transformation and "palette->grayscale" detection.
 Improved dithering.
 Multi-lingual error and warning message support.
 Complete sRGB transformation (presently it simply uses gamma=0.45455).
+Make profile checking optional via a png_set_something() call.
 Man pages for function calls.
 Better documentation.
 Better filter selection

arm/arm_init.c

@@ -1,9 +1,9 @@
 
 /* arm_init.c - NEON optimised filter functions
  *
- * Copyright (c) 2013 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.5.15 [%RDATE%]
+ * Last changed in libpng 1.6.10 [March 6, 2014]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -16,134 +16,36 @@
 
 #include "../pngpriv.h"
 
-#ifdef PNG_ARM_NEON_SUPPORTED
+#ifdef PNG_READ_SUPPORTED
+#if PNG_ARM_NEON_OPT > 0
 #ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */
-#include <signal.h> /* for sig_atomic_t */
-
-#ifdef __ANDROID__
-/* Linux provides access to information about CPU capabilites via
- * /proc/self/auxv, however Android blocks this while still claiming to be
- * Linux.  The Andoid NDK, however, provides appropriate support.
+/* WARNING: it is strongly recommended that you do not build libpng with
+ * run-time checks for CPU features if at all possible.  In the case of the ARM
+ * NEON instructions there is no processor-specific way of detecting the
+ * presence of the required support, therefore run-time detection is extremely
+ * OS specific.
  *
- * Documentation: http://www.kandroid.org/ndk/docs/CPU-ARM-NEON.html
+ * You may set the macro PNG_ARM_NEON_FILE to the file name of file containing
+ * a fragment of C source code which defines the png_have_neon function.  There
+ * are a number of implementations in contrib/arm-neon, but the only one that
+ * has partial support is contrib/arm-neon/linux.c - a generic Linux
+ * implementation which reads /proc/cpufino.
  */
-#include <cpu-features.h>
+#ifndef PNG_ARM_NEON_FILE
+#  ifdef __linux__
+#     define PNG_ARM_NEON_FILE "contrib/arm-neon/linux.c"
+#  endif
+#endif
 
-static int
-png_have_neon(png_structp png_ptr)
-{
-   /* This is a whole lot easier than the mess below, however it is probably
-    * implemented as below, therefore it is better to cache the result (these
-    * function calls may be slow!)
-    */
-   PNG_UNUSED(png_ptr)
-   return android_getCpuFamily() == ANDROID_CPU_FAMILY_ARM &&
-      (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
-}
-#elif defined(__linux__)
-/* The generic __linux__ implementation requires reading /proc/self/auxv and
- * looking at each element for one that records NEON capabilities.
- */
-#include <unistd.h> /* for POSIX 1003.1 */
-#include <errno.h>  /* for EINTR */
+#ifdef PNG_ARM_NEON_FILE
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <elf.h>
-#include <asm/hwcap.h>
+#include <signal.h> /* for sig_atomic_t */
+static int png_have_neon(png_structp png_ptr);
+#include PNG_ARM_NEON_FILE
 
-/* A read call may be interrupted, in which case it returns -1 and sets errno to
- * EINTR if nothing was done, otherwise (if something was done) a partial read
- * may result.
- */
-static size_t
-safe_read(png_structp png_ptr, int fd, void *buffer_in, size_t nbytes)
-{
-   size_t ntotal = 0;
-   char *buffer = png_voidcast(char*, buffer_in);
-
-   while (nbytes > 0)
-   {
-      unsigned int nread;
-      int iread;
-
-      /* Passing nread > INT_MAX to read is implementation defined in POSIX
-       * 1003.1, therefore despite the unsigned argument portable code must
-       * limit the value to INT_MAX!
-       */
-      if (nbytes > INT_MAX)
-         nread = INT_MAX;
-
-      else
-         nread = (unsigned int)/*SAFE*/nbytes;
-
-      iread = read(fd, buffer, nread);
-
-      if (iread == -1)
-      {
-         /* This is the devil in the details, a read can terminate early with 0
-          * bytes read because of EINTR, yet it still returns -1 otherwise end
-          * of file cannot be distinguished.
-          */
-         if (errno != EINTR)
-         {
-            png_warning(png_ptr, "/proc read failed");
-            return 0; /* I.e. a permanent failure */
-         }
-      }
-
-      else if (iread < 0)
-      {
-         /* Not a valid 'read' result: */
-         png_warning(png_ptr, "OS /proc read bug");
-         return 0;
-      }
-
-      else if (iread > 0)
-      {
-         /* Continue reading until a permanent failure, or EOF */
-         buffer += iread;
-         nbytes -= (unsigned int)/*SAFE*/iread;
-         ntotal += (unsigned int)/*SAFE*/iread;
-      }
-
-      else
-         return ntotal;
-   }
-
-   return ntotal; /* nbytes == 0 */
-}
-
-static int
-png_have_neon(png_structp png_ptr)
-{
-   int fd = open("/proc/self/auxv", O_RDONLY);
-   Elf32_auxv_t aux;
-
-   /* Failsafe: failure to open means no NEON */
-   if (fd == -1)
-   {
-      png_warning(png_ptr, "/proc/self/auxv open failed");
-      return 0;
-   }
-
-   while (safe_read(png_ptr, fd, &aux, sizeof aux) == sizeof aux)
-   {
-      if (aux.a_type == AT_HWCAP && (aux.a_un.a_val & HWCAP_NEON) != 0)
-      {
-         close(fd);
-         return 1;
-      }
-   }
-
-   close(fd);
-   return 0;
-}
-#else
-   /* We don't know how to do a run-time check on this system */
-#  error "no support for run-time ARM NEON checks"
-#endif /* OS checks */
+#else  /* PNG_ARM_NEON_FILE */
+#  error "PNG_ARM_NEON_FILE undefined: no support for run-time ARM NEON checks"
+#endif /* PNG_ARM_NEON_FILE */
 #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
 
 #ifndef PNG_ALIGNED_MEMORY_SUPPORTED
@@ -153,6 +55,16 @@ png_have_neon(png_structp png_ptr)
 void
 png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
 {
+   /* The switch statement is compiled in for ARM_NEON_API, the call to
+    * png_have_neon is compiled in for ARM_NEON_CHECK.  If both are defined
+    * the check is only performed if the API has not set the NEON option on
+    * or off explicitly.  In this case the check controls what happens.
+    *
+    * If the CHECK is not compiled in and the option is UNSET the behavior prior
+    * to 1.6.7 was to use the NEON code - this was a bug caused by having the
+    * wrong order of the 'ON' and 'default' cases.  UNSET now defaults to OFF,
+    * as documented in png.h
+    */
 #ifdef PNG_ARM_NEON_API_SUPPORTED
    switch ((pp->options >> PNG_ARM_NEON) & 3)
    {
@@ -177,13 +89,14 @@ png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
          break;
 #endif
 #endif /* PNG_ARM_NEON_CHECK_SUPPORTED */
+
 #ifdef PNG_ARM_NEON_API_SUPPORTED
+      default: /* OFF or INVALID */
+         return;
+
       case PNG_OPTION_ON:
          /* Option turned on */
          break;
-
-      default: /* OFF or INVALID */
-         return;
    }
 #endif
 
@@ -216,4 +129,5 @@ png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
           png_read_filter_row_paeth4_neon;
    }
 }
-#endif /* FILTER_OPTIMIZATIONS && __arm__ && __ARM_NEON__ */
+#endif /* PNG_ARM_NEON_OPT > 0 */
+#endif /* PNG_READ_SUPPORTED */

arm/filter_neon.S

@@ -1,9 +1,9 @@
 
 /* filter_neon.S - NEON optimised filter functions
  *
- * Copyright (c) 2011 Glenn Randers-Pehrson
+ * Copyright (c) 2013 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Last changed in libpng 1.6.8 [December 19, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -11,17 +11,26 @@
  */
 
 /* This is required to get the symbol renames, which are #defines, and also
- * includes the value of PNG_FILTER_OPTIMIZATIONS.
+ * includes the definition (or not) of PNG_ARM_NEON_OPT and
+ * PNG_ARM_NEON_IMPLEMENTATION.
  */
 #define PNG_VERSION_INFO_ONLY
 #include "../pngpriv.h"
 
-#if defined(PNG_FILTER_OPTIMIZATIONS) && defined(__arm__) && \
-   defined(__ARM_NEON__)
 #if defined(__linux__) && defined(__ELF__)
 .section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
 #endif
 
+/* Assembler NEON support - only works for 32-bit ARM (i.e. it does not work for
+ * ARM64).  The code in arm/filter_neon_intrinsics.c supports ARM64, however it
+ * only works if -mfpu=neon is specified on the GCC command line.  See pngpriv.h
+ * for the logic which sets PNG_USE_ARM_NEON_ASM:
+ */
+#if PNG_ARM_NEON_IMPLEMENTATION == 2 /* hand-coded assembler */
+
+#ifdef PNG_READ_SUPPORTED
+#if PNG_ARM_NEON_OPT > 0
+
 #ifdef __ELF__
 #   define ELF
 #else
@@ -232,4 +241,6 @@ func    png_read_filter_row_paeth3_neon, export=1
 
         pop             {r4,pc}
 endfunc
-#endif /* FILTER_OPTIMIZATIONS && __arm__ && __ARM_NEON__ */
+#endif /* PNG_ARM_NEON_OPT > 0 */
+#endif /* PNG_READ_SUPPORTED */
+#endif /* PNG_ARM_NEON_IMPLEMENTATION == 2 (assembler) */

arm/filter_neon_intrinsics.c

@@ -0,0 +1,372 @@
+
+/* filter_neon_intrinsics.c - NEON optimised filter functions
+ *
+ * Copyright (c) 2013 Glenn Randers-Pehrson
+ * Written by James Yu <james.yu at linaro.org>, October 2013.
+ * Based on filter_neon.S, written by Mans Rullgard, 2011.
+ *
+ * Last changed in libpng 1.6.8 [December 19, 2013]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ */
+
+#include "../pngpriv.h"
+
+/* This code requires -mfpu=neon on the command line: */
+#if PNG_ARM_NEON_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
+
+#include <arm_neon.h>
+
+/* libpng row pointers are not necessarily aligned to any particular boundary,
+ * however this code will only work with appropriate alignment.  arm/arm_init.c
+ * checks for this (and will not compile unless it is done). This code uses
+ * variants of png_aligncast to avoid compiler warnings.
+ */
+#define png_ptr(type,pointer) png_aligncast(type *,pointer)
+#define png_ptrc(type,pointer) png_aligncastconst(const type *,pointer)
+
+/* The following relies on a variable 'temp_pointer' being declared with type
+ * 'type'.  This is written this way just to hide the GCC strict aliasing
+ * warning; note that the code is safe because there never is an alias between
+ * the input and output pointers.
+ */
+#define png_ldr(type,pointer)\
+   (temp_pointer = png_ptr(type,pointer), *temp_pointer)
+
+#ifdef PNG_READ_SUPPORTED
+#if PNG_ARM_NEON_OPT > 0
+
+void
+png_read_filter_row_up_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+   png_const_bytep pp = prev_row;
+
+   for (; rp < rp_stop; rp += 16, pp += 16)
+   {
+      uint8x16_t qrp, qpp;
+
+      qrp = vld1q_u8(rp);
+      qpp = vld1q_u8(pp);
+      qrp = vaddq_u8(qrp, qpp);
+      vst1q_u8(rp, qrp);
+   }
+}
+
+void
+png_read_filter_row_sub3_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+
+   uint8x16_t vtmp = vld1q_u8(rp);
+   uint8x8x2_t *vrpt = png_ptr(uint8x8x2_t, &vtmp);
+   uint8x8x2_t vrp = *vrpt;
+
+   uint8x8x4_t vdest;
+   vdest.val[3] = vdup_n_u8(0);
+
+   for (; rp < rp_stop;)
+   {
+      uint8x8_t vtmp1, vtmp2;
+      uint32x2_t *temp_pointer;
+
+      vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
+      vdest.val[0] = vadd_u8(vdest.val[3], vrp.val[0]);
+      vtmp2 = vext_u8(vrp.val[0], vrp.val[1], 6);
+      vdest.val[1] = vadd_u8(vdest.val[0], vtmp1);
+
+      vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
+      vdest.val[2] = vadd_u8(vdest.val[1], vtmp2);
+      vdest.val[3] = vadd_u8(vdest.val[2], vtmp1);
+
+      vtmp = vld1q_u8(rp + 12);
+      vrpt = png_ptr(uint8x8x2_t, &vtmp);
+      vrp = *vrpt;
+
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
+      rp += 3;
+   }
+
+   PNG_UNUSED(prev_row)
+}
+
+void
+png_read_filter_row_sub4_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+
+   uint8x8x4_t vdest;
+   vdest.val[3] = vdup_n_u8(0);
+
+   for (; rp < rp_stop; rp += 16)
+   {
+      uint32x2x4_t vtmp = vld4_u32(png_ptr(uint32_t,rp));
+      uint8x8x4_t *vrpt = png_ptr(uint8x8x4_t,&vtmp);
+      uint8x8x4_t vrp = *vrpt;
+      uint32x2x4_t *temp_pointer;
+
+      vdest.val[0] = vadd_u8(vdest.val[3], vrp.val[0]);
+      vdest.val[1] = vadd_u8(vdest.val[0], vrp.val[1]);
+      vdest.val[2] = vadd_u8(vdest.val[1], vrp.val[2]);
+      vdest.val[3] = vadd_u8(vdest.val[2], vrp.val[3]);
+      vst4_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2x4_t,&vdest), 0);
+   }
+
+   PNG_UNUSED(prev_row)
+}
+
+void
+png_read_filter_row_avg3_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_const_bytep pp = prev_row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+
+   uint8x16_t vtmp;
+   uint8x8x2_t *vrpt;
+   uint8x8x2_t vrp;
+   uint8x8x4_t vdest;
+   vdest.val[3] = vdup_n_u8(0);
+
+   vtmp = vld1q_u8(rp);
+   vrpt = png_ptr(uint8x8x2_t,&vtmp);
+   vrp = *vrpt;
+
+   for (; rp < rp_stop; pp += 12)
+   {
+      uint8x8_t vtmp1, vtmp2, vtmp3;
+
+      uint8x8x2_t *vppt;
+      uint8x8x2_t vpp;
+
+      uint32x2_t *temp_pointer;
+
+      vtmp = vld1q_u8(pp);
+      vppt = png_ptr(uint8x8x2_t,&vtmp);
+      vpp = *vppt;
+
+      vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
+      vdest.val[0] = vhadd_u8(vdest.val[3], vpp.val[0]);
+      vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+
+      vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 3);
+      vtmp3 = vext_u8(vrp.val[0], vrp.val[1], 6);
+      vdest.val[1] = vhadd_u8(vdest.val[0], vtmp2);
+      vdest.val[1] = vadd_u8(vdest.val[1], vtmp1);
+
+      vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 6);
+      vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
+
+      vtmp = vld1q_u8(rp + 12);
+      vrpt = png_ptr(uint8x8x2_t,&vtmp);
+      vrp = *vrpt;
+
+      vdest.val[2] = vhadd_u8(vdest.val[1], vtmp2);
+      vdest.val[2] = vadd_u8(vdest.val[2], vtmp3);
+
+      vtmp2 = vext_u8(vpp.val[1], vpp.val[1], 1);
+
+      vdest.val[3] = vhadd_u8(vdest.val[2], vtmp2);
+      vdest.val[3] = vadd_u8(vdest.val[3], vtmp1);
+
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
+      rp += 3;
+   }
+}
+
+void
+png_read_filter_row_avg4_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+   png_const_bytep pp = prev_row;
+
+   uint8x8x4_t vdest;
+   vdest.val[3] = vdup_n_u8(0);
+
+   for (; rp < rp_stop; rp += 16, pp += 16)
+   {
+      uint32x2x4_t vtmp;
+      uint8x8x4_t *vrpt, *vppt;
+      uint8x8x4_t vrp, vpp;
+      uint32x2x4_t *temp_pointer;
+
+      vtmp = vld4_u32(png_ptr(uint32_t,rp));
+      vrpt = png_ptr(uint8x8x4_t,&vtmp);
+      vrp = *vrpt;
+      vtmp = vld4_u32(png_ptrc(uint32_t,pp));
+      vppt = png_ptr(uint8x8x4_t,&vtmp);
+      vpp = *vppt;
+
+      vdest.val[0] = vhadd_u8(vdest.val[3], vpp.val[0]);
+      vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+      vdest.val[1] = vhadd_u8(vdest.val[0], vpp.val[1]);
+      vdest.val[1] = vadd_u8(vdest.val[1], vrp.val[1]);
+      vdest.val[2] = vhadd_u8(vdest.val[1], vpp.val[2]);
+      vdest.val[2] = vadd_u8(vdest.val[2], vrp.val[2]);
+      vdest.val[3] = vhadd_u8(vdest.val[2], vpp.val[3]);
+      vdest.val[3] = vadd_u8(vdest.val[3], vrp.val[3]);
+
+      vst4_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2x4_t,&vdest), 0);
+   }
+}
+
+static uint8x8_t
+paeth(uint8x8_t a, uint8x8_t b, uint8x8_t c)
+{
+   uint8x8_t d, e;
+   uint16x8_t p1, pa, pb, pc;
+
+   p1 = vaddl_u8(a, b); /* a + b */
+   pc = vaddl_u8(c, c); /* c * 2 */
+   pa = vabdl_u8(b, c); /* pa */
+   pb = vabdl_u8(a, c); /* pb */
+   pc = vabdq_u16(p1, pc); /* pc */
+
+   p1 = vcleq_u16(pa, pb); /* pa <= pb */
+   pa = vcleq_u16(pa, pc); /* pa <= pc */
+   pb = vcleq_u16(pb, pc); /* pb <= pc */
+
+   p1 = vandq_u16(p1, pa); /* pa <= pb && pa <= pc */
+
+   d = vmovn_u16(pb);
+   e = vmovn_u16(p1);
+
+   d = vbsl_u8(d, b, c);
+   e = vbsl_u8(e, a, d);
+
+   return e;
+}
+
+void
+png_read_filter_row_paeth3_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_const_bytep pp = prev_row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+
+   uint8x16_t vtmp;
+   uint8x8x2_t *vrpt;
+   uint8x8x2_t vrp;
+   uint8x8_t vlast = vdup_n_u8(0);
+   uint8x8x4_t vdest;
+   vdest.val[3] = vdup_n_u8(0);
+
+   vtmp = vld1q_u8(rp);
+   vrpt = png_ptr(uint8x8x2_t,&vtmp);
+   vrp = *vrpt;
+
+   for (; rp < rp_stop; pp += 12)
+   {
+      uint8x8x2_t *vppt;
+      uint8x8x2_t vpp;
+      uint8x8_t vtmp1, vtmp2, vtmp3;
+      uint32x2_t *temp_pointer;
+
+      vtmp = vld1q_u8(pp);
+      vppt = png_ptr(uint8x8x2_t,&vtmp);
+      vpp = *vppt;
+
+      vdest.val[0] = paeth(vdest.val[3], vpp.val[0], vlast);
+      vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+
+      vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 3);
+      vtmp2 = vext_u8(vpp.val[0], vpp.val[1], 3);
+      vdest.val[1] = paeth(vdest.val[0], vtmp2, vpp.val[0]);
+      vdest.val[1] = vadd_u8(vdest.val[1], vtmp1);
+
+      vtmp1 = vext_u8(vrp.val[0], vrp.val[1], 6);
+      vtmp3 = vext_u8(vpp.val[0], vpp.val[1], 6);
+      vdest.val[2] = paeth(vdest.val[1], vtmp3, vtmp2);
+      vdest.val[2] = vadd_u8(vdest.val[2], vtmp1);
+
+      vtmp1 = vext_u8(vrp.val[1], vrp.val[1], 1);
+      vtmp2 = vext_u8(vpp.val[1], vpp.val[1], 1);
+
+      vtmp = vld1q_u8(rp + 12);
+      vrpt = png_ptr(uint8x8x2_t,&vtmp);
+      vrp = *vrpt;
+
+      vdest.val[3] = paeth(vdest.val[2], vtmp2, vtmp3);
+      vdest.val[3] = vadd_u8(vdest.val[3], vtmp1);
+
+      vlast = vtmp2;
+
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[0]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[1]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[2]), 0);
+      rp += 3;
+      vst1_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2_t,&vdest.val[3]), 0);
+      rp += 3;
+   }
+}
+
+void
+png_read_filter_row_paeth4_neon(png_row_infop row_info, png_bytep row,
+   png_const_bytep prev_row)
+{
+   png_bytep rp = row;
+   png_bytep rp_stop = row + row_info->rowbytes;
+   png_const_bytep pp = prev_row;
+
+   uint8x8_t vlast = vdup_n_u8(0);
+   uint8x8x4_t vdest;
+   vdest.val[3] = vdup_n_u8(0);
+
+   for (; rp < rp_stop; rp += 16, pp += 16)
+   {
+      uint32x2x4_t vtmp;
+      uint8x8x4_t *vrpt, *vppt;
+      uint8x8x4_t vrp, vpp;
+      uint32x2x4_t *temp_pointer;
+
+      vtmp = vld4_u32(png_ptr(uint32_t,rp));
+      vrpt = png_ptr(uint8x8x4_t,&vtmp);
+      vrp = *vrpt;
+      vtmp = vld4_u32(png_ptrc(uint32_t,pp));
+      vppt = png_ptr(uint8x8x4_t,&vtmp);
+      vpp = *vppt;
+
+      vdest.val[0] = paeth(vdest.val[3], vpp.val[0], vlast);
+      vdest.val[0] = vadd_u8(vdest.val[0], vrp.val[0]);
+      vdest.val[1] = paeth(vdest.val[0], vpp.val[1], vpp.val[0]);
+      vdest.val[1] = vadd_u8(vdest.val[1], vrp.val[1]);
+      vdest.val[2] = paeth(vdest.val[1], vpp.val[2], vpp.val[1]);
+      vdest.val[2] = vadd_u8(vdest.val[2], vrp.val[2]);
+      vdest.val[3] = paeth(vdest.val[2], vpp.val[3], vpp.val[2]);
+      vdest.val[3] = vadd_u8(vdest.val[3], vrp.val[3]);
+
+      vlast = vpp.val[3];
+
+      vst4_lane_u32(png_ptr(uint32_t,rp), png_ldr(uint32x2x4_t,&vdest), 0);
+   }
+}
+
+#endif /* PNG_ARM_NEON_OPT > 0 */
+#endif /* PNG_READ_SUPPORTED */
+#endif /* PNG_ARM_NEON_IMPLEMENTATION == 1 (intrinsics) */

autogen.sh

@@ -9,15 +9,15 @@
 #
 # For regular ("tarball") distributions all the files should exist.  We do not
 # want them to be updated *under any circumstances*.  It should never be
-# necessary to rune autogen.sh because ./configure --enable-maintainer-mode says
-# what to do if Makeile.am or configure.ac are changed.
+# necessary to run autogen.sh because ./configure --enable-maintainer-mode says
+# what to do if Makefile.am or configure.ac are changed.
 #
 # It is *probably* OK to update the files on a GIT checkout, because they have
 # come from the local tools, but leave that to the user who is assumed to know
 # whether it is ok or required.
 #
 # This script is intended to work without arguments, there are, however, hidden
-# arguments for (a) use while testing the script and (b) to fix up systems that
+# arguments (a) for use while testing the script and (b) to fix up systems that
 # have been broken.  If (b) is required the script prompts for the correct
 # options.  For this reason the options are *NOT* documented in the help; this
 # is deliberate; UTSL.
@@ -76,6 +76,10 @@ done
 libpng_autotools_files="Makefile.in aclocal.m4 config.guess config.h.in\
    config.sub configure depcomp install-sh ltmain.sh missing test-driver"
 #
+# Files generated by versions of configue >2.68 or automake >1.13 (i.e. later
+# versions than those required by configure.ac):
+libpng_autotools_extra="compile"
+#
 # These are separate because 'maintainer-clean' does not remove them.
 libpng_libtool_files="scripts/libtool.m4 scripts/ltoptions.m4\
    scripts/ltsugar.m4 scripts/ltversion.m4 scripts/lt~obsolete.m4"
@@ -94,6 +98,7 @@ libpng_configure_dirs=".deps"
 # of Makefile.  These functions do the two bits of cleaning.
 clean_autotools(){
    rm -rf $libpng_autotools_files $libpng_libtool_files $libpng_autotools_dirs
+   rm -rf $libpng_autotools_extra
 }
 
 clean_configure(){
@@ -198,7 +203,7 @@ case "$mode" in
          echo "  You can run autoreconf yourself if you don't like maintainer"
          echo "  mode and you can also just run autoreconf -f -i to initialize"
          echo "  everything in the first place; this script is only for"
-         echo "  compatiblity with prior releases."
+         echo "  compatibility with prior releases."
          exit 1
       else
          exec >&2

configure.ac

@@ -18,7 +18,7 @@ AC_PREREQ([2.68])
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.7.0beta08],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.7.0beta41],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -27,7 +27,7 @@ AC_CONFIG_MACRO_DIR([scripts])
 # dist-xz requires automake 1.11 or later
 # 1.12.2 fixes a security issue in 1.11.2 and 1.12.1
 # 1.13 is required for parallel tests
-AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules])
+AM_INIT_AUTOMAKE([1.13 foreign dist-xz color-tests silent-rules subdir-objects])
 # The following line causes --disable-maintainer-mode to be the default to
 # configure, this is necessary because libpng distributions cannot rely on the
 # time stamps of the autotools generated files being correct
@@ -39,7 +39,7 @@ dnl automake, so the following is not necessary (and is not defined anyway):
 dnl AM_PREREQ([1.11.2])
 dnl stop configure from automagically running automake
 
-PNGLIB_VERSION=1.7.0beta08
+PNGLIB_VERSION=1.7.0beta41
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=7
 PNGLIB_RELEASE=0
@@ -79,7 +79,7 @@ fi
 
 # This is a remnant of the old cc -E validation, where it may have been
 # necessary to use a different preprocessor for .dfn files
-DFNCPP="$CPP"
+DFNCPP="$CPP -E"
 AC_SUBST(DFNCPP)
 
 # -Werror cannot be passed to GCC in CFLAGS because configure will fail (it
@@ -137,12 +137,20 @@ AC_CHECK_FUNCS([memset memcpy strncpy],,
 
 # floor and ceil are required for FLOATING_POINT, but they can be turned off on
 # the configure command line (and they are independent.)  Default is to 'on'
-AC_ARG_ENABLE([floating-point],[Enable floating point APIs],,
-              [enable_floating_point=yes])
-AC_ARG_ENABLE([fixed-point],[Enable fixed point APIs],,
-              [enable_fixed_point=yes])
-AC_ARG_ENABLE([floating-arithmetic],[Use floating point arithmetic internally],,
-              [enable_floating_arithmetic=yes])
+AC_ARG_ENABLE([floating-point],
+   AS_HELP_STRING([[[--enabled-floating-point]]],
+      [Enable floating point APIs (default: yes)]),,
+   [enable_floating_point=yes])
+
+AC_ARG_ENABLE([fixed-point],
+   AS_HELP_STRING([[[--enable-fixed-point]]],
+      [Enable fixed point APIs (default: yes)]),,
+   [enable_fixed_point=yes])
+
+AC_ARG_ENABLE([floating-arithmetic],
+   AS_HELP_STRING([[[--enable-floating-arithmetic]]],
+      [Use floating point arithmetic internally (default: yes)]),,
+   [enable_floating_arithmetic=yes])
 
 # Check for a requirement for math library support
 if test "$enable_floating_arithmetic" = yes
@@ -286,7 +294,7 @@ AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, test "$have_ld_version_script" = "yes")
 if test "$have_ld_version_script" = "yes"; then
     AC_MSG_CHECKING([for symbol prefix])
     SYMBOL_PREFIX=`echo "PREFIX=__USER_LABEL_PREFIX__" \
-                  | ${CPP-${CC-gcc} -E} - 2>&1 \
+                  | ${DFNCPP-${CC-gcc -E}} - 2>&1 \
                   | ${EGREP-grep} "^PREFIX=" \
                   | ${SED-sed} -e "s:^PREFIX=::" -e "s:__USER_LABEL_PREFIX__::"`
     AC_SUBST(SYMBOL_PREFIX)
@@ -334,35 +342,93 @@ AC_ARG_WITH(libpng-prefix,
     fi])
 AM_CONDITIONAL([DO_PNG_PREFIX], [test "${with_libpng_prefix:-no}" != "no"])
 
-# Because GCC by default assembles code with an executable stack, even though it
-# compiles C code with a non-executable stack, it is necessary to do a fixup
-# here (this may by GCC specific)
-AC_SUBST([AM_CCASFLAGS], [-Wa,--noexecstack])
+# Control over what links are made for installed files.  Versioned files are
+# always installed, when the following options are turned on corresponding
+# unversioned links are also created (normally as symbolic links):
+AC_ARG_ENABLE([unversioned-links],
+   AS_HELP_STRING([[[--enable-unversioned-links]]],
+      [Installed libpng header files are placed in a versioned subdirectory]
+      [and installed libpng library (including DLL) files are versioned.]
+      [If this option is enabled unversioned links will be created pointing to]
+      [the corresponding installed files.  If you use libpng.pc or]
+      [libpng-config for all builds you do not need these links, but if you]
+      [compile programs directly they will typically #include <png.h> and]
+      [link with -lpng; in that case you need the links.]
+      [The links can be installed manually using 'make install-header-links']
+      [and 'make install-library-links' and can be removed using the]
+      [corresponding uninstall- targets.  If you do enable this option every]
+      [libpng 'make install' will recreate the links to point to the just]
+      [installed version of libpng.  The default is to create the links;]
+      [use --disable-unversioned-links to change this]))
+
+# The AM_CONDITIONAL test is written so that the default is enabled;
+# --disable-unversioned-links must be given to turn the option off.
+AM_CONDITIONAL([DO_INSTALL_LINKS],[test "$enable_unversioned_links" != "no"])
+
+AC_ARG_ENABLE([unversioned-libpng-pc],
+   AS_HELP_STRING([[[--enable-unversioned-libpng-pc]]],
+      [Install the configuration file 'libpng.pc' as a link to the versioned]
+      [version.  This is done by default - use --disable-unversioned-libpng-pc]
+      [to change this.]))
+AM_CONDITIONAL([DO_INSTALL_LIBPNG_PC],
+   [test "$enable_unversioned_libpng_pc" != "no"])
+
+AC_ARG_ENABLE([unversioned-libpng-config],
+   AS_HELP_STRING([[[--enable-unversioned-libpng-config]]],
+      [Install the configuration file 'libpng-config' as a link to the]
+      [versioned version.  This is done by default - use]
+      [--disable-unversioned-libpng-config to change this.]))
+AM_CONDITIONAL([DO_INSTALL_LIBPNG_CONFIG],
+   [test "$enable_unversioned_libpng_config" != "no"])
+
+# HOST SPECIFIC OPTIONS
+# =====================
+#
+# ARM
+# ===
+#
+# ARM NEON (SIMD) support.
 
 AC_ARG_ENABLE([arm-neon],
    AS_HELP_STRING([[[--enable-arm-neon]]],
-      [Enable ARM NEON optimizations: =off, check, api, on:]
-      [off: disable the optimizations; check: use internal checking code]
+      [Enable ARM NEON optimizations: =no/off, check, api, yes/on:]
+      [no/off: disable the optimizations; check: use internal checking code]
       [(deprecated and poorly supported); api: disable by default, enable by]
-      [a call to png_set_option; on: turn on unconditionally.  The]
-      [default is 'on' if __ARM_NEON__ is defined, otherwise 'off'.]),
+      [a call to png_set_option; yes/on: turn on unconditionally.]
+      [If not specified: determined by the compiler.]),
    [case "$enableval" in
-      off)
-         AC_DEFINE([PNG_NO_ARM_NEON], [],
-                   [Disable ARM Neon optimizations]);;
+      no|off)
+         # disable the default enabling on __ARM_NEON__ systems:
+         AC_DEFINE([PNG_ARM_NEON_OPT], [0],
+                   [Disable ARM Neon optimizations])
+         # Prevent inclusion of the assembler files below:
+         enable_arm_neon=no;;
       check)
          AC_DEFINE([PNG_ARM_NEON_CHECK_SUPPORTED], [],
                    [Check for ARM Neon support at run-time]);;
       api)
          AC_DEFINE([PNG_ARM_NEON_API_SUPPORTED], [],
                    [Turn on ARM Neon optimizations at run-time]);;
-      on)
-         AC_DEFINE([PNG_ARM_NEON_SUPPORTED], [],
-                   [Enable ARM Neon optimizations]);;
+      yes|on)
+         AC_DEFINE([PNG_ARM_NEON_OPT], [2],
+                   [Enable ARM Neon optimizations])
+         AC_MSG_WARN([--enable-arm-neon: please specify 'check' or 'api', if]
+            [you want the optimizations unconditionally pass -mfpu=neon]
+            [to the compiler.]);;
       *)
-         AC_MSG_ERROR([arm-neon: option value required (off/check/api/on)]);;
+         AC_MSG_ERROR([--enable-arm-neon=${enable_arm_neon}: invalid value])
    esac])
-AM_CONDITIONAL([PNG_ARM_NEON], [test "${enable_arm_neon:-no}" != "no"])
+
+# Add ARM specific files to all builds where the host_cpu is arm ('arm*') or
+# where ARM optimizations were explicitly requested (this allows a fallback if a
+# future host CPU does not match 'arm*')
+
+AM_CONDITIONAL([PNG_ARM_NEON],
+   [test "$enable_arm_neon" != 'no' &&
+    case "$host_cpu" in
+      arm*|aarch64*) :;;
+      *)    test "$enable_arm_neon" != '';;
+    esac])
 
 AC_MSG_NOTICE([[Extra options for compiler: $PNG_COPTS]])
 

contrib/arm-neon/README

@@ -0,0 +1,83 @@
+OPERATING SYSTEM SPECIFIC ARM NEON DETECTION
+--------------------------------------------
+
+Detection of the ability to exexcute ARM NEON on an ARM processor requires
+operating system support.  (The information is not available in user mode.)
+
+HOW TO USE THIS
+---------------
+
+This directory contains C code fragments that can be included in arm/arm_init.c
+by setting the macro PNG_ARM_NEON_FILE to the file name in "" or <> at build
+time.  This setting is not recorded in pnglibconf.h and can be changed simply by
+rebuilding arm/arm_init.o with the required macro definition.
+
+For any of this code to be used the ARM NEON code must be enabled and run time
+checks must be supported.  I.e.:
+
+#if PNG_ARM_NEON_OPT > 0
+#ifdef PNG_ARM_NEON_CHECK_SUPPORTED
+
+This is done in a 'configure' build by passing configure the argument:
+
+   --enable-arm-neon=check
+
+Apart from the basic Linux implementation in contrib/arm-neon/linux.c this code
+is unsupported.  That means that it is not even compiled on a regular basis and
+may be broken in any given minor release.
+
+FILE FORMAT
+-----------
+
+Each file documents its testing status as of the last time it was tested (which
+may have been a long time ago):
+
+STATUS: one of:
+   SUPPORTED: This indicates that the file is included in the regularly
+         performed test builds and bugs are fixed when discovered.
+   COMPILED: This indicates that the code did compile at least once.  See the
+         more detailed description for the extent to which the result was
+         successful.
+   TESTED: This means the code was fully compiled into the libpng test programs
+         and these were run at least once.
+
+BUG REPORTS: an email address to which to send reports of problems
+
+The file is a fragment of C code. It should not define any 'extern' symbols;
+everything should be static.  It must define the function:
+
+static int png_have_neon(png_structp png_ptr);
+
+That function must return 1 if ARM NEON instructions are supported, 0 if not.
+It must not execute png_error unless it detects a bug.  A png_error will prevent
+the reading of the PNG and in the future, writing too.
+
+BUG REPORTS
+-----------
+
+If you mail a bug report for any file that is not SUPPORTED there may only be
+limited response.  Consider fixing it and sending a patch to fix the problem -
+this is more likely to result in action.
+
+CONTRIBUTIONS
+-------------
+
+You may send contributions of new implementations to
+png-mng-implement@sourceforge.net.  Please write code in strict C90 C where
+possible.  Obviously OS dependencies are to be expected.  If you submit code you
+must have the authors permission and it must have a license that is acceptable
+to the current maintainer; in particular that license must permit modification
+and redistribution.
+
+Please try to make the contribution a single file and give the file a clear and
+unambiguous name that identifies the target OS.  If multiple files really are
+required put them all in a sub-directory.
+
+You must also be prepared to handle bug reports from users of the code, either
+by joining the png-mng-implement mailing list or by providing an email for the
+"BUG REPORTS" entry or both.  Please make sure that the header of the file
+contains the STATUS and BUG REPORTS fields as above.
+
+Please list the OS requirements as precisely as possible.  Ideally you should
+also list the environment in which the code has been tested and certainly list
+any environments where you suspect it might not work.

contrib/arm-neon/android-ndk.c

@@ -0,0 +1,39 @@
+/* contrib/arm-neon/android-ndk.c
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by John Bowler, 2014.
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: COMPILED, UNTESTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon implemented for the Android NDK, see:
+ *
+ * Documentation:
+ *    http://www.kandroid.org/ndk/docs/CPU-ARM-NEON.html
+ *    http://code.google.com/p/android/issues/detail?id=49065
+ *
+ * NOTE: this requires that libpng is built against the Android NDK and linked
+ * with an implementation of the Android ARM 'cpu-features' library.  The code
+ * has been compiled only, not linked: no version of the library has been found,
+ * only the header files exist in the NDK.
+ */
+#include <cpu-features.h>
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+   /* This is a whole lot easier than the linux code, however it is probably
+    * implemented as below, therefore it is better to cache the result (these
+    * function calls may be slow!)
+    */
+   PNG_UNUSED(png_ptr)
+   return android_getCpuFamily() == ANDROID_CPU_FAMILY_ARM &&
+      (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
+}

contrib/arm-neon/linux-auxv.c

@@ -0,0 +1,120 @@
+/* contrib/arm-neon/linux-auxv.c
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by Mans Rullgard, 2011.
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ * 
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: COMPILED, TESTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon implemented for Linux versions which allow access to
+ * /proc/self/auxv.  This is probably faster, cleaner and safer than the code to
+ * read /proc/cpuinfo in contrib/arm-neon/linux, however it is yet another piece
+ * of potentially untested code and has more complex dependencies than the code
+ * to read cpuinfo.
+ *
+ * This generic __linux__ implementation requires reading /proc/self/auxv and
+ * looking at each element for one that records NEON capabilities.
+ */
+#include <unistd.h> /* for POSIX 1003.1 */
+#include <errno.h>  /* for EINTR */
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <elf.h>
+#include <asm/hwcap.h>
+
+/* A read call may be interrupted, in which case it returns -1 and sets errno to
+ * EINTR if nothing was done, otherwise (if something was done) a partial read
+ * may result.
+ */
+static size_t
+safe_read(png_structp png_ptr, int fd, void *buffer_in, size_t nbytes)
+{
+   size_t ntotal = 0;
+   char *buffer = png_voidcast(char*, buffer_in);
+
+   while (nbytes > 0)
+   {
+      unsigned int nread;
+      int iread;
+
+      /* Passing nread > INT_MAX to read is implementation defined in POSIX
+       * 1003.1, therefore despite the unsigned argument portable code must
+       * limit the value to INT_MAX!
+       */
+      if (nbytes > INT_MAX)
+         nread = INT_MAX;
+
+      else
+         nread = (unsigned int)/*SAFE*/nbytes;
+
+      iread = read(fd, buffer, nread);
+
+      if (iread == -1)
+      {
+         /* This is the devil in the details, a read can terminate early with 0
+          * bytes read because of EINTR, yet it still returns -1 otherwise end
+          * of file cannot be distinguished.
+          */
+         if (errno != EINTR)
+         {
+            png_warning(png_ptr, "/proc read failed");
+            return 0; /* I.e., a permanent failure */
+         }
+      }
+
+      else if (iread < 0)
+      {
+         /* Not a valid 'read' result: */
+         png_warning(png_ptr, "OS /proc read bug");
+         return 0;
+      }
+
+      else if (iread > 0)
+      {
+         /* Continue reading until a permanent failure, or EOF */
+         buffer += iread;
+         nbytes -= (unsigned int)/*SAFE*/iread;
+         ntotal += (unsigned int)/*SAFE*/iread;
+      }
+
+      else
+         return ntotal;
+   }
+
+   return ntotal; /* nbytes == 0 */
+}
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+   int fd = open("/proc/self/auxv", O_RDONLY);
+   Elf32_auxv_t aux;
+
+   /* Failsafe: failure to open means no NEON */
+   if (fd == -1)
+   {
+      png_warning(png_ptr, "/proc/self/auxv open failed");
+      return 0;
+   }
+
+   while (safe_read(png_ptr, fd, &aux, sizeof aux) == sizeof aux)
+   {
+      if (aux.a_type == AT_HWCAP && (aux.a_un.a_val & HWCAP_NEON) != 0)
+      {
+         close(fd);
+         return 1;
+      }
+   }
+
+   close(fd);
+   return 0;
+}

contrib/arm-neon/linux.c

@@ -0,0 +1,159 @@
+/* contrib/arm-neon/linux.c
+ *
+ * Copyright (c) 2014 Glenn Randers-Pehrson
+ * Written by John Bowler, 2014.
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * SEE contrib/arm-neon/README before reporting bugs
+ *
+ * STATUS: SUPPORTED
+ * BUG REPORTS: png-mng-implement@sourceforge.net
+ *
+ * png_have_neon implemented for Linux by reading the widely available
+ * pseudo-file /proc/cpuinfo.
+ *
+ * This code is strict ANSI-C and is probably moderately portable, it does
+ * however use <stdio.h> and assumes that /proc/cpuinfo is never localized.
+ */
+#include <stdio.h>
+
+static int
+png_have_neon(png_structp png_ptr)
+{
+   FILE *f = fopen("/proc/cpuinfo", "rb");
+
+   if (f != NULL)
+   {
+      /* This is a simple state machine which reads the input byte-by-byte until
+       * it gets a match on the 'neon' feature or reaches the end of the stream.
+       */
+      static const char ch_feature[] = { 70, 69, 65, 84, 85, 82, 69, 83 };
+      static const char ch_neon[] = { 78, 69, 79, 78 };
+
+      enum
+      {
+         StartLine, Feature, Colon, StartTag, Neon, HaveNeon, SkipTag, SkipLine
+      }  state;
+      int counter;
+
+      for (state=StartLine, counter=0;;)
+      {
+         int ch = fgetc(f);
+
+         if (ch == EOF)
+         {
+            /* EOF means error or end-of-file, return false; neon at EOF is
+             * assumed to be a mistake.
+             */
+            fclose(f);
+            return 0;
+         }
+
+         switch (state)
+         {
+            case StartLine:
+               /* Match spaces at the start of line */
+               if (ch <= 32) /* skip control characters and space */
+                  break;
+
+               counter=0;
+               state = Feature;
+               /* FALL THROUGH */
+
+            case Feature:
+               /* Match 'FEATURE', ASCII case insensitive. */
+               if ((ch & ~0x20) == ch_feature[counter])
+               {
+                  if (++counter == (sizeof ch_feature))
+                     state = Colon;
+                  break;
+               }
+               
+               /* did not match 'feature' */
+               state = SkipLine;
+               /* FALL THROUGH */
+
+            case SkipLine:
+            skipLine:
+               /* Skip everything until we see linefeed or carriage return */
+               if (ch != 10 && ch != 13)
+                  break;
+
+               state = StartLine;
+               break;
+
+            case Colon:
+               /* Match any number of space or tab followed by ':' */
+               if (ch == 32 || ch == 9)
+                  break;
+
+               if (ch == 58) /* i.e. ':' */
+               {
+                  state = StartTag;
+                  break;
+               }
+
+               /* Either a bad line format or a 'feature' prefix followed by
+                * other characters.
+                */
+               state = SkipLine;
+               goto skipLine;
+
+            case StartTag:
+               /* Skip space characters before a tag */
+               if (ch == 32 || ch == 9)
+                  break;
+
+               state = Neon;
+               counter = 0;
+               /* FALL THROUGH */
+
+            case Neon:
+               /* Look for 'neon' tag */
+               if ((ch & ~0x20) == ch_neon[counter])
+               {
+                  if (++counter == (sizeof ch_neon))
+                     state = HaveNeon;
+                  break;
+               }
+
+               state = SkipTag;
+               /* FALL THROUGH */
+
+            case SkipTag:
+               /* Skip non-space characters */
+               if (ch == 10 || ch == 13)
+                  state = StartLine;
+
+               else if (ch == 32 || ch == 9)
+                  state = StartTag;
+               break;
+
+            case HaveNeon:
+               /* Have seen a 'neon' prefix, but there must be a space or new
+                * line character to terminate it.
+                */
+               if (ch == 10 || ch == 13 || ch == 32 || ch == 9)
+               {
+                  fclose(f);
+                  return 1;
+               }
+
+               state = SkipTag;
+               break;
+
+            default:
+               png_error(png_ptr, "png_have_neon: internal error (bug)");
+         }
+      }
+   }
+
+   else
+      png_warning(png_ptr, "/proc/cpuinfo open failed");
+
+   return 0;
+}

contrib/conftest/README

@@ -0,0 +1,49 @@
+This directory contains test configuration files, currently always '.dfa' files
+intended to be used in the build by setting the make macro DFA_XTRA to the name
+of the file.
+
+These files are used in release validation of the 'configure' builds of libpng
+by building 'make check', or 'make all-am' for cross-builds, with each .dfa
+file.
+
+The files in this directory may change between minor releases, however
+contributions describing specific builds of libpng are welcomed.  There is no
+guarantee that libpng will continue to build with such configurations; support
+for given configurations can be, and has been, dropped between successive minor
+releases.  However if a .dfa file describing a configuration is not in this
+directory it is very unlikely that it will be tested before a minor release!
+
+You can use these .dfa files as the basis of new configurations.  Files in this
+directory should not have any use restrictions or restrictive licenses.
+
+This directory is not included in the .zip and .7z distributions, which do
+not contain 'configure' scripts.
+
+DOCUMENTATION
+=============
+
+Examples:
+   ${srcdir}/pngusr.dfa
+   ${srcdir}/contrib/pngminim/*/pngusr.dfa
+
+Documentation of the options:
+   ${srcdir}/scripts/pnglibconf.dfa
+
+Documentation of the file format:
+   ${srcdir}/scripts/options.awk
+
+FILE NAMING
+===========
+
+File names in this directory may NOT contain any of the five characters:
+
+   - , + * ?
+
+Neither may they contain any space character.
+
+While other characters may be used it is strongly suggested that file names be
+limited to lower case Latiin alphabetic characters (a-z), digits (0-9) and, if
+necessary the underscore (_) character.  File names should be about 8 characters
+long (excluding the .dfa extension).  Submitted .dfa files should have names
+between 7 and 16 characters long, shorter names (6 characters or less) are
+reserved for standard tests.

contrib/conftest/read.dfa

@@ -0,0 +1,58 @@
+# read.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+#  To the extent possible under law, the author has waived all copyright and
+#  related or neighboring rights to this work.  This work is published from:
+#  United States.
+#
+# Build libpng with basic read support.  This enables the lowest level libpng
+# read API - the one where the calling code has to use a loop to read each row.
+# At present this is the API used by most programs.
+#
+# Support is enabled only for those chunks and transformations that are
+# typically required - others can be added easily.
+#
+
+everything = off
+
+# The sequential read code is enabled here; the progressive code can be used
+# instead but there is no point enabling both.
+
+option SEQUENTIAL_READ on
+
+# Likewise it is pointless enabling both fixed and floating point APIs.  Choose
+# one or the other for both the API and the internal math.
+
+#Fixed point:
+#option FIXED_POINT on
+#option FLOATING_ARITHMETIC off
+
+#Floating point:
+option FLOATING_POINT on
+option FLOATING_ARITHMETIC on
+
+# Basic error handling, IO and user memory support.  The latter allows the
+# application program to provide its own implementations of 'malloc' and 'free'.
+option SETJMP on
+option STDIO on
+option USER_MEM on
+
+# To read the full set of PNG images correctly interlace, transparency and
+# 16-bit support is required.  The application can implement interlace itself,
+# but very few do and it's no longer possible to disable it when READ is
+# enabled.
+option READ_tRNS on
+option READ_16BIT on
+
+# Everything else is application dependent.  This file assumes the app handles
+# all the native PNG bit layouts, so it doesn't need any of layout change
+# transforms, but needs libpng to perform gamma correction.  It doesn't do any
+# colorspace stuff and ignores the 'significant bit' information.
+#
+# If your app always expands the image to a limited set of bit layouts you
+# probably want to consider using the simplified API instead of the low level
+# one - see png.h and s_read.dfa.
+option READ_GAMMA on

contrib/conftest/s_read.dfa

@@ -0,0 +1,35 @@
+# s_read.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+#  To the extent possible under law, the author has waived all copyright and
+#  related or neighboring rights to this work.  This work is published from:
+#  United States.
+#
+# Build libpng with simplified read support (only).  This builds a minimal
+# libpng able to read all PNG formats and convert them into a small number of
+# well understood memory formats.
+#
+
+everything = off
+
+option SIMPLIFIED_READ on
+
+# It isn't necessary to chose fixed or floating point for the APIs because the
+# simplified API doesn't need fixed or floating point numbers.  It is necessary
+# to chose an internal math implementation.  The default (because of 'everything
+# = off') is fixed point - turn the floating point implementation on if you have
+# hardware floating point or prefer your software floating point implementation.
+option FLOATING_ARITHMETIC on
+
+# This is not strictly necessary, but without it the message strings in the API
+# will not be filled in
+option ERROR_TEXT on
+
+# Switching these options on enables the 'AFIRST' and 'BGR' formats - you don't
+# need this if you don't use them, they just allow the in-memory layout to be
+# changed to match common hardware formats.
+option SIMPLIFIED_READ_AFIRST on
+option SIMPLIFIED_READ_BGR on

contrib/conftest/s_write.dfa

@@ -0,0 +1,33 @@
+# s_write.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+#  To the extent possible under law, the author has waived all copyright and
+#  related or neighboring rights to this work.  This work is published from:
+#  United States.
+#
+# Build libpng with (just) simplified write support
+#
+
+everything = off
+
+option SIMPLIFIED_WRITE on
+
+# It isn't necessary to chose fixed or floating point for the APIs because the
+# simplified API doesn't need fixed or floating point numbers.  It is necessary
+# to chose an internal math implementation.  The default (because of 'everything
+# = off') is fixed point - turn the floating point implementation on if you have
+# hardware floating point or prefer your software floating point implementation.
+option FLOATING_ARITHMETIC on
+
+# This is not strictly necessary, but without it the message strings in the API
+# will not be filled in
+option ERROR_TEXT on
+
+# Switching these options on enables the 'AFIRST' and 'BGR' formats - you don't
+# need this if you don't use them, they just allow the in-memory layout to be
+# changed to match common hardware formats.
+option SIMPLIFIED_WRITE_AFIRST on
+option SIMPLIFIED_WRITE_BGR on

contrib/conftest/simple.dfa

@@ -0,0 +1,36 @@
+# simple.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+#  To the extent possible under law, the author has waived all copyright and
+#  related or neighboring rights to this work.  This work is published from:
+#  United States.
+#
+# Build libpng with just the simplified APIs (read and write).
+#
+
+everything = off
+
+option SIMPLIFIED_WRITE on
+option SIMPLIFIED_READ on
+
+# It isn't necessary to chose fixed or floating point for the APIs because the
+# simplified API doesn't need fixed or floating point numbers.  It is necessary
+# to chose an internal math implementation.  The default (because of 'everything
+# = off') is fixed point - turn the floating point implementation on if you have
+# hardware floating point or prefer your software floating point implementation.
+option FLOATING_ARITHMETIC on
+
+# This is not strictly necessary, but without it the message strings in the API
+# will not be filled in
+option ERROR_TEXT on
+
+# Switching these options on enables the 'AFIRST' and 'BGR' formats - you don't
+# need this if you don't use them, they just allow the in-memory layout to be
+# changed to match common hardware formats.
+option SIMPLIFIED_READ_AFIRST on
+option SIMPLIFIED_READ_BGR on
+option SIMPLIFIED_WRITE_AFIRST on
+option SIMPLIFIED_WRITE_BGR on

contrib/conftest/write.dfa

@@ -0,0 +1,45 @@
+# write.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2013
+# Usage rights:
+#  To the extent possible under law, the author has waived all copyright and
+#  related or neighboring rights to this work.  This work is published from:
+#  United States.
+#
+# Build libpng with no read support and minimal write support.
+#
+
+everything = off
+
+# Switch on the write code - this makes a minimalist encoder
+
+option WRITE on
+
+# Choose fixed or floating point APIs and arithmetic.  The choices are
+# independent but normally they will match.  It is typically better to use the
+# floating point if you have floating point hardware.  If you don't know, or
+# (perhaps) to make libpng smaller used fixed point throughout.
+
+#Fixed point:
+#option FIXED_POINT on
+#option FLOATING_ARITHMETIC off
+
+#Floating point:
+option FLOATING_POINT on
+option FLOATING_ARITHMETIC on
+
+# Basic error handling, IO and user memory support.  The latter allows the
+# application program to provide its own implementations of 'malloc' and 'free'.
+option SETJMP on
+option STDIO on
+option USER_MEM on
+
+# Everything else is optional.  Unlike the read code in libpng the write code
+# does not need to deal with arbitrary formats, so only add support for things
+# you really do write!  For example you might only write sRGB images, sometimes
+# with transparency and never write 16 bit images, so:
+option WRITE_sRGB on
+option WRITE_tRNS on
+#option WRITE_16BIT off (this is the default with 'everything = off')

contrib/examples/iccfrompng.c

@@ -6,9 +6,9 @@
  * United States.
  *
  * Extract any icc profiles found in the given PNG files.  This is a simple
- * example of a program which extracts information from the header of a PNG file
+ * example of a program that extracts information from the header of a PNG file
  * without processing the image.  Notice that some header information may occur
- * after the image data, textual data and comments are an example; the approach
+ * after the image data. Textual data and comments are an example; the approach
  * in this file won't work reliably for such data because it only looks for the
  * information in the section of the file that preceeds the image data.
  *

contrib/examples/pngpixel.c

@@ -8,7 +8,7 @@
  * Read a single pixel value from a PNG file.
  *
  * This code illustrates basic 'by-row' reading of a PNG file using libpng.
- * Rows are read until a particular pixel is found, the value of this pixel is
+ * Rows are read until a particular pixel is found; the value of this pixel is
  * then printed on stdout.
  *
  * The code illustrates how to do this on interlaced as well as non-interlaced
@@ -56,7 +56,7 @@ component(png_const_bytep row, png_uint_32 x, unsigned int c,
       case 8: return row[0];
       case 16: return (row[0] << 8) + row[1];
       default:
-         /* This should never happen, it indicates a bug in this program or in
+         /* This should never happen; it indicates a bug in this program or in
           * libpng itself:
           */
          fprintf(stderr, "pngpixel: invalid bit depth %u\n", bit_depth);
@@ -132,7 +132,7 @@ print_pixel(png_structp png_ptr, png_infop info_ptr, png_const_bytep row,
          return;
 
       default:
-         png_error(png_ptr, "invalid color type");
+         png_error(png_ptr, "pngpixel: invalid color type");
    }
 }
 

contrib/gregbook/Makefile.mingw32

@@ -47,7 +47,8 @@ CC = gcc
 #CC = i386-mingw32msvc-gcc #	e.g., Linux -> Win32 cross-compilation
 LD = $(CC)
 RM = rm -f
-CFLAGS = -O -Wall $(INCS) $(MINGW_CCFLAGS)
+CPPFLAGS = $(INCS)
+CFLAGS = -O -Wall $(MINGW_CCFLAGS)
 # [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
 # [-ansi, -pedantic and -W can also be used]
 LDFLAGS = $(MINGW_LDFLAGS)
@@ -85,10 +86,10 @@ EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $<
 
 %.pic$(O): %.c
-	$(CC) -c $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) -DPNG_BUILD_DLL -o $@ $<
 
 
 # dependencies --------------------------------------------------------------

contrib/gregbook/Makefile.sgi

@@ -53,7 +53,8 @@ CC = cc
 LD = cc
 RM = rm -f
 # ABI must be the same as that used to build libpng.
-ABI=
+ABI =
+CPPFLAGS =
 CFLAGS = $(ABI) -O -fullwarn $(INCS)
 LDFLAGS = $(ABI)
 O = .o
@@ -73,7 +74,7 @@ EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $<
 
 
 # dependencies --------------------------------------------------------------

contrib/gregbook/Makefile.unx

@@ -64,7 +64,8 @@ WLIBSs = $(PNGLIBs) $(ZLIBs)
 CC = gcc
 LD = gcc
 RM = rm -f
-CFLAGS = -O -Wall $(INCS) -DFEATURE_LOOP
+CPPFLAGS = $(INCS) -DFEATURE_LOOP
+CFLAGS = -O -Wall
 # [note that -Wall is a gcc-specific compilation flag ("most warnings on")]
 # [-ansi, -pedantic and -W can also be used]
 LDFLAGS =
@@ -92,7 +93,7 @@ EXES = $(STATIC_EXES) $(DYNAMIC_EXES)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $<
 
 
 # dependencies --------------------------------------------------------------

contrib/gregbook/Makefile.w32

@@ -53,7 +53,8 @@ WLIBS = $(PNGLIB) $(ZLIB)
 CC = cl
 LD = link
 RM = del
-CFLAGS = -nologo -O -W3 $(INCS) $(cvars)
+CPPFLAGS = $(INCS)
+CFLAGS = -nologo -O -W3 $(cvars)
 # [note that -W3 is an MSVC-specific compilation flag ("all warnings on")]
 # [see %devstudio%\vc\include\win32.mak for cvars macro definition]
 O = .obj
@@ -76,7 +77,7 @@ EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) -c $(CPPFLAGS) $(CFLAGS) $<
 
 
 # dependencies --------------------------------------------------------------

contrib/gregbook/readpng2.c

@@ -69,6 +69,7 @@ static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
                                  png_uint_32 row_num, int pass);
 static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr);
 static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);
+static void readpng2_warning_handler(png_structp png_ptr, png_const_charp msg);
 
 
 
@@ -104,7 +105,7 @@ int readpng2_init(mainprog_info *mainprog_ptr)
     /* could also replace libpng warning-handler (final NULL), but no need: */
 
     png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
-      readpng2_error_handler, NULL);
+      readpng2_error_handler, readpng2_warning_handler);
     if (!png_ptr)
         return 4;   /* out of memory */
 
@@ -447,6 +448,8 @@ static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr)
 
     /* all done */
 
+    (void)info_ptr; /* Unused */
+
     return;
 }
 
@@ -467,7 +470,12 @@ void readpng2_cleanup(mainprog_info *mainprog_ptr)
 }
 
 
-
+static void readpng2_warning_handler(png_structp png_ptr, png_const_charp msg)
+{
+    fprintf(stderr, "readpng2 libpng warning: %s\n", msg);
+    fflush(stderr);
+    (void)png_ptr; /* Unused */
+}
 
 
 static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)

contrib/gregbook/readppm.c

@@ -163,8 +163,12 @@ uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
 
     /* now we can go ahead and just read the whole image */
 
-    fread(image_data, 1L, rowbytes*height, saved_infile);
-
+    if (fread(image_data, 1L, rowbytes*height, saved_infile) <
+       rowbytes*height) {
+        free (image_data);
+        image_data = NULL;
+        return NULL;
+    }
 
     return image_data;
 }

contrib/libtests/gentests.sh

@@ -1,8 +1,8 @@
 #!/bin/sh
 #
-# Copyright (c) 2012 John Cunningham Bowler
+# Copyright (c) 2013 John Cunningham Bowler
 #
-# Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+# Last changed in libpng 1.6.0 [February 14, 2013]
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer

contrib/libtests/makepng.c

@@ -1,8 +1,8 @@
 /* makepng.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/libtests/pngstest.c

@@ -1,9 +1,9 @@
 /*-
  * pngstest.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.8 [December 19, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -517,14 +517,23 @@ static void format_default(format_list *pf, int redundant)
 
       for (f=0; f<FORMAT_COUNT; ++f)
       {
-         /* Eliminate redundant settings. */
-         /* BGR is meaningless if no color: */
-         if ((f & PNG_FORMAT_FLAG_COLOR) == 0 && (f & PNG_FORMAT_FLAG_BGR) != 0)
+         /* Eliminate redundant and unsupported settings. */
+#        ifdef PNG_FORMAT_BGR_SUPPORTED
+            /* BGR is meaningless if no color: */
+            if ((f & PNG_FORMAT_FLAG_COLOR) == 0 &&
+               (f & PNG_FORMAT_FLAG_BGR) != 0)
+#        else
+            if ((f & 0x10U/*HACK: fixed value*/) != 0)
+#        endif
             continue;
 
          /* AFIRST is meaningless if no alpha: */
-         if ((f & PNG_FORMAT_FLAG_ALPHA) == 0 &&
-            (f & PNG_FORMAT_FLAG_AFIRST) != 0)
+#        ifdef PNG_FORMAT_AFIRST_SUPPORTED
+            if ((f & PNG_FORMAT_FLAG_ALPHA) == 0 &&
+               (f & PNG_FORMAT_FLAG_AFIRST) != 0)
+#        else
+            if ((f & 0x20U/*HACK: fixed value*/) != 0)
+#        endif
             continue;
 
          format_set(pf, f);
@@ -786,6 +795,7 @@ gp_ga8(Pixel *p, png_const_voidp pb)
    p->a = pp[1];
 }
 
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
 static void
 gp_ag8(Pixel *p, png_const_voidp pb)
 {
@@ -794,6 +804,7 @@ gp_ag8(Pixel *p, png_const_voidp pb)
    p->r = p->g = p->b = pp[1];
    p->a = pp[0];
 }
+#endif
 
 static void
 gp_rgb8(Pixel *p, png_const_voidp pb)
@@ -806,6 +817,7 @@ gp_rgb8(Pixel *p, png_const_voidp pb)
    p->a = 255;
 }
 
+#ifdef PNG_FORMAT_BGR_SUPPORTED
 static void
 gp_bgr8(Pixel *p, png_const_voidp pb)
 {
@@ -816,6 +828,7 @@ gp_bgr8(Pixel *p, png_const_voidp pb)
    p->b = pp[0];
    p->a = 255;
 }
+#endif
 
 static void
 gp_rgba8(Pixel *p, png_const_voidp pb)
@@ -828,6 +841,7 @@ gp_rgba8(Pixel *p, png_const_voidp pb)
    p->a = pp[3];
 }
 
+#ifdef PNG_FORMAT_BGR_SUPPORTED
 static void
 gp_bgra8(Pixel *p, png_const_voidp pb)
 {
@@ -838,7 +852,9 @@ gp_bgra8(Pixel *p, png_const_voidp pb)
    p->b = pp[0];
    p->a = pp[3];
 }
+#endif
 
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
 static void
 gp_argb8(Pixel *p, png_const_voidp pb)
 {
@@ -849,7 +865,9 @@ gp_argb8(Pixel *p, png_const_voidp pb)
    p->b = pp[3];
    p->a = pp[0];
 }
+#endif
 
+#if defined(PNG_FORMAT_AFIRST_SUPPORTED) && defined(PNG_FORMAT_BGR_SUPPORTED)
 static void
 gp_abgr8(Pixel *p, png_const_voidp pb)
 {
@@ -860,6 +878,7 @@ gp_abgr8(Pixel *p, png_const_voidp pb)
    p->b = pp[1];
    p->a = pp[0];
 }
+#endif
 
 static void
 gp_g16(Pixel *p, png_const_voidp pb)
@@ -879,6 +898,7 @@ gp_ga16(Pixel *p, png_const_voidp pb)
    p->a = pp[1];
 }
 
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
 static void
 gp_ag16(Pixel *p, png_const_voidp pb)
 {
@@ -887,6 +907,7 @@ gp_ag16(Pixel *p, png_const_voidp pb)
    p->r = p->g = p->b = pp[1];
    p->a = pp[0];
 }
+#endif
 
 static void
 gp_rgb16(Pixel *p, png_const_voidp pb)
@@ -899,6 +920,7 @@ gp_rgb16(Pixel *p, png_const_voidp pb)
    p->a = 65535;
 }
 
+#ifdef PNG_FORMAT_BGR_SUPPORTED
 static void
 gp_bgr16(Pixel *p, png_const_voidp pb)
 {
@@ -909,6 +931,7 @@ gp_bgr16(Pixel *p, png_const_voidp pb)
    p->b = pp[0];
    p->a = 65535;
 }
+#endif
 
 static void
 gp_rgba16(Pixel *p, png_const_voidp pb)
@@ -921,6 +944,7 @@ gp_rgba16(Pixel *p, png_const_voidp pb)
    p->a = pp[3];
 }
 
+#ifdef PNG_FORMAT_BGR_SUPPORTED
 static void
 gp_bgra16(Pixel *p, png_const_voidp pb)
 {
@@ -931,7 +955,9 @@ gp_bgra16(Pixel *p, png_const_voidp pb)
    p->b = pp[0];
    p->a = pp[3];
 }
+#endif
 
+#ifdef PNG_FORMAT_AFIRST_SUPPORTED
 static void
 gp_argb16(Pixel *p, png_const_voidp pb)
 {
@@ -942,7 +968,9 @@ gp_argb16(Pixel *p, png_const_voidp pb)
    p->b = pp[3];
    p->a = pp[0];
 }
+#endif
 
+#if defined(PNG_FORMAT_AFIRST_SUPPORTED) && defined(PNG_FORMAT_BGR_SUPPORTED)
 static void
 gp_abgr16(Pixel *p, png_const_voidp pb)
 {
@@ -953,6 +981,7 @@ gp_abgr16(Pixel *p, png_const_voidp pb)
    p->b = pp[1];
    p->a = pp[0];
 }
+#endif
 
 /* Given a format, return the correct one of the above functions. */
 static void (*
@@ -966,29 +995,35 @@ get_pixel(png_uint_32 format))(Pixel *p, png_const_voidp pb)
    {
       if (format & PNG_FORMAT_FLAG_COLOR)
       {
-         if (format & PNG_FORMAT_FLAG_BGR)
-         {
-            if (format & PNG_FORMAT_FLAG_ALPHA)
+#        ifdef PNG_FORMAT_BGR_SUPPORTED
+            if (format & PNG_FORMAT_FLAG_BGR)
             {
-               if (format & PNG_FORMAT_FLAG_AFIRST)
-                  return gp_abgr16;
+               if (format & PNG_FORMAT_FLAG_ALPHA)
+               {
+#                 ifdef PNG_FORMAT_AFIRST_SUPPORTED
+                     if (format & PNG_FORMAT_FLAG_AFIRST)
+                        return gp_abgr16;
+
+                     else
+#                 endif
+                     return gp_bgra16;
+               }
 
                else
-                  return gp_bgra16;
+                  return gp_bgr16;
             }
 
             else
-               return gp_bgr16;
-         }
-
-         else
+#        endif
          {
             if (format & PNG_FORMAT_FLAG_ALPHA)
             {
-               if (format & PNG_FORMAT_FLAG_AFIRST)
-                  return gp_argb16;
+#              ifdef PNG_FORMAT_AFIRST_SUPPORTED
+                  if (format & PNG_FORMAT_FLAG_AFIRST)
+                     return gp_argb16;
 
-               else
+                  else
+#              endif
                   return gp_rgba16;
             }
 
@@ -1001,10 +1036,12 @@ get_pixel(png_uint_32 format))(Pixel *p, png_const_voidp pb)
       {
          if (format & PNG_FORMAT_FLAG_ALPHA)
          {
-            if (format & PNG_FORMAT_FLAG_AFIRST)
-               return gp_ag16;
+#           ifdef PNG_FORMAT_AFIRST_SUPPORTED
+               if (format & PNG_FORMAT_FLAG_AFIRST)
+                  return gp_ag16;
 
-            else
+               else
+#           endif
                return gp_ga16;
          }
 
@@ -1017,29 +1054,35 @@ get_pixel(png_uint_32 format))(Pixel *p, png_const_voidp pb)
    {
       if (format & PNG_FORMAT_FLAG_COLOR)
       {
-         if (format & PNG_FORMAT_FLAG_BGR)
-         {
-            if (format & PNG_FORMAT_FLAG_ALPHA)
+#        ifdef PNG_FORMAT_BGR_SUPPORTED
+            if (format & PNG_FORMAT_FLAG_BGR)
             {
-               if (format & PNG_FORMAT_FLAG_AFIRST)
-                  return gp_abgr8;
+               if (format & PNG_FORMAT_FLAG_ALPHA)
+               {
+#                 ifdef PNG_FORMAT_AFIRST_SUPPORTED
+                     if (format & PNG_FORMAT_FLAG_AFIRST)
+                        return gp_abgr8;
+
+                     else
+#                 endif
+                     return gp_bgra8;
+               }
 
                else
-                  return gp_bgra8;
+                  return gp_bgr8;
             }
 
             else
-               return gp_bgr8;
-         }
-
-         else
+#        endif
          {
             if (format & PNG_FORMAT_FLAG_ALPHA)
             {
-               if (format & PNG_FORMAT_FLAG_AFIRST)
-                  return gp_argb8;
+#              ifdef PNG_FORMAT_AFIRST_SUPPORTED
+                  if (format & PNG_FORMAT_FLAG_AFIRST)
+                     return gp_argb8;
 
-               else
+                  else
+#              endif
                   return gp_rgba8;
             }
 
@@ -1052,10 +1095,12 @@ get_pixel(png_uint_32 format))(Pixel *p, png_const_voidp pb)
       {
          if (format & PNG_FORMAT_FLAG_ALPHA)
          {
-            if (format & PNG_FORMAT_FLAG_AFIRST)
-               return gp_ag8;
+#           ifdef PNG_FORMAT_AFIRST_SUPPORTED
+               if (format & PNG_FORMAT_FLAG_AFIRST)
+                  return gp_ag8;
 
-            else
+               else
+#           endif
                return gp_ga8;
          }
 
@@ -2618,13 +2663,15 @@ component_loc(png_byte loc[4], png_uint_32 format)
 
       loc[2] = 1;
 
-      if (format & PNG_FORMAT_FLAG_BGR)
-      {
-         loc[1] = 2;
-         loc[3] = 0;
-      }
+#     ifdef PNG_FORMAT_BGR_SUPPORTED
+         if (format & PNG_FORMAT_FLAG_BGR)
+         {
+            loc[1] = 2;
+            loc[3] = 0;
+         }
 
-      else
+         else
+#     endif
       {
          loc[1] = 0;
          loc[3] = 2;
@@ -2639,15 +2686,17 @@ component_loc(png_byte loc[4], png_uint_32 format)
 
    if (format & PNG_FORMAT_FLAG_ALPHA)
    {
-      if (format & PNG_FORMAT_FLAG_AFIRST)
-      {
-         loc[0] = 0;
-         ++loc[1];
-         ++loc[2];
-         ++loc[3];
-      }
+#     ifdef PNG_FORMAT_AFIRST_SUPPORTED
+         if (format & PNG_FORMAT_FLAG_AFIRST)
+         {
+            loc[0] = 0;
+            ++loc[1];
+            ++loc[2];
+            ++loc[3];
+         }
 
-      else
+         else
+#     endif
          loc[0] = channels;
 
       ++channels;
@@ -3017,17 +3066,25 @@ read_file(Image *image, png_uint_32 format, png_const_colorp background)
          return logerror(image, "memory init: ", image->file_name, "");
    }
 
-   else if (image->input_file != NULL)
-   {
-      if (!png_image_begin_read_from_stdio(&image->image, image->input_file))
-         return logerror(image, "stdio init: ", image->file_name, "");
-   }
+#  ifdef PNG_STDIO_SUPPORTED
+      else if (image->input_file != NULL)
+      {
+         if (!png_image_begin_read_from_stdio(&image->image, image->input_file))
+            return logerror(image, "stdio init: ", image->file_name, "");
+      }
 
-   else
-   {
-      if (!png_image_begin_read_from_file(&image->image, image->file_name))
-         return logerror(image, "file init: ", image->file_name, "");
-   }
+      else
+      {
+         if (!png_image_begin_read_from_file(&image->image, image->file_name))
+            return logerror(image, "file init: ", image->file_name, "");
+      }
+#  else
+      else
+      {
+         return logerror(image, "unsupported file/stdio init: ",
+            image->file_name, "");
+      }
+#  endif
 
    /* This must be set after the begin_read call: */
    if (image->opts & sRGB_16BIT)
@@ -3466,11 +3523,19 @@ main(int argc, char **argv)
          memset(gpc_error_via_linear, 0, sizeof gpc_error_via_linear);
       }
       else if (strcmp(arg, "--file") == 0)
-         opts |= READ_FILE;
+#        ifdef PNG_STDIO_SUPPORTED
+            opts |= READ_FILE;
+#        else
+            return 77; /* skipped: no support */
+#        endif
       else if (strcmp(arg, "--memory") == 0)
          opts &= ~READ_FILE;
       else if (strcmp(arg, "--stdio") == 0)
-         opts |= USE_STDIO;
+#        ifdef PNG_STDIO_SUPPORTED
+            opts |= USE_STDIO;
+#        else
+            return 77; /* skipped: no support */
+#        endif
       else if (strcmp(arg, "--name") == 0)
          opts &= ~USE_STDIO;
       else if (strcmp(arg, "--verbose") == 0)

contrib/libtests/pngunknown.c

@@ -1,8 +1,8 @@
 
 /* pngunknown.c - test the read side unknown chunk handling
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.10 [March 6, 2014]
+ * Copyright (c) 2014 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -30,7 +30,19 @@
 #  include "../../png.h"
 #endif
 
-#ifdef PNG_READ_SUPPORTED
+/* Since this program tests the ability to change the unknown chunk handling
+ * these must be defined:
+ */
+#if defined(PNG_SET_UNKNOWN_CHUNKS_SUPPORTED) &&\
+   defined(PNG_READ_SUPPORTED)
+
+/* One of these must be defined to allow us to find out what happened.  It is
+ * still useful to set unknown chunk handling without either of these in order
+ * to cause *known* chunks to be discarded.  This can be a significant
+ * efficiency gain, but it can't really be tested here.
+ */
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED) ||\
+   defined(PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED)
 
 #if PNG_LIBPNG_VER < 10500
 /* This deliberately lacks the PNG_CONST. */
@@ -75,43 +87,74 @@ typedef png_byte *png_const_bytep;
 #  define png_const_structp png_structp
 #endif
 
+#if PNG_LIBPNG_VER < 10700
+   /* Copied from libpng 1.7.0 png.h */
+#define PNG_u2(b1, b2) (((unsigned int)(b1) << 8) + (b2))
 
-/* Copied from pngpriv.h */
-#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
-#define PNG_CHUNK(b1,b2,b3,b4) \
-   (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
+#define PNG_U16(b1, b2) ((png_uint_16)PNG_u2(b1, b2))
+#define PNG_U32(b1, b2, b3, b4)\
+   (((png_uint_32)PNG_u2(b1, b2) << 16) + PNG_u2(b3, b4))
 
-#define png_IHDR PNG_CHUNK( 73,  72,  68,  82)
-#define png_IDAT PNG_CHUNK( 73,  68,  65,  84)
-#define png_IEND PNG_CHUNK( 73,  69,  78,  68)
-#define png_PLTE PNG_CHUNK( 80,  76,  84,  69)
-#define png_bKGD PNG_CHUNK( 98,  75,  71,  68)
-#define png_cHRM PNG_CHUNK( 99,  72,  82,  77)
-#define png_gAMA PNG_CHUNK(103,  65,  77,  65)
-#define png_hIST PNG_CHUNK(104,  73,  83,  84)
-#define png_iCCP PNG_CHUNK(105,  67,  67,  80)
-#define png_iTXt PNG_CHUNK(105,  84,  88, 116)
-#define png_oFFs PNG_CHUNK(111,  70,  70, 115)
-#define png_pCAL PNG_CHUNK(112,  67,  65,  76)
-#define png_sCAL PNG_CHUNK(115,  67,  65,  76)
-#define png_pHYs PNG_CHUNK(112,  72,  89, 115)
-#define png_sBIT PNG_CHUNK(115,  66,  73,  84)
-#define png_sPLT PNG_CHUNK(115,  80,  76,  84)
-#define png_sRGB PNG_CHUNK(115,  82,  71,  66)
-#define png_sTER PNG_CHUNK(115,  84,  69,  82)
-#define png_tEXt PNG_CHUNK(116,  69,  88, 116)
-#define png_tIME PNG_CHUNK(116,  73,  77,  69)
-#define png_tRNS PNG_CHUNK(116,  82,  78,  83)
-#define png_zTXt PNG_CHUNK(122,  84,  88, 116)
-#define png_vpAg PNG_CHUNK('v', 'p', 'A', 'g')
+/* Constants for known chunk types.
+ */
+#define png_IDAT PNG_U32( 73,  68,  65,  84)
+#define png_IEND PNG_U32( 73,  69,  78,  68)
+#define png_IHDR PNG_U32( 73,  72,  68,  82)
+#define png_PLTE PNG_U32( 80,  76,  84,  69)
+#define png_bKGD PNG_U32( 98,  75,  71,  68)
+#define png_cHRM PNG_U32( 99,  72,  82,  77)
+#define png_fRAc PNG_U32(102,  82,  65,  99) /* registered, not defined */
+#define png_gAMA PNG_U32(103,  65,  77,  65)
+#define png_gIFg PNG_U32(103,  73,  70, 103)
+#define png_gIFt PNG_U32(103,  73,  70, 116) /* deprecated */
+#define png_gIFx PNG_U32(103,  73,  70, 120)
+#define png_hIST PNG_U32(104,  73,  83,  84)
+#define png_iCCP PNG_U32(105,  67,  67,  80)
+#define png_iTXt PNG_U32(105,  84,  88, 116)
+#define png_oFFs PNG_U32(111,  70,  70, 115)
+#define png_pCAL PNG_U32(112,  67,  65,  76)
+#define png_pHYs PNG_U32(112,  72,  89, 115)
+#define png_sBIT PNG_U32(115,  66,  73,  84)
+#define png_sCAL PNG_U32(115,  67,  65,  76)
+#define png_sPLT PNG_U32(115,  80,  76,  84)
+#define png_sRGB PNG_U32(115,  82,  71,  66)
+#define png_sTER PNG_U32(115,  84,  69,  82)
+#define png_tEXt PNG_U32(116,  69,  88, 116)
+#define png_tIME PNG_U32(116,  73,  77,  69)
+#define png_tRNS PNG_U32(116,  82,  78,  83)
+#define png_zTXt PNG_U32(122,  84,  88, 116)
 
 /* Test on flag values as defined in the spec (section 5.4): */
-#define PNG_CHUNK_ANCILLARY(c )   (1 & ((c) >> 29))
+#define PNG_CHUNK_ANCILLARY(c)    (1 & ((c) >> 29))
 #define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLARY(c))
 #define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
 #define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
 
+#endif /* PNG_LIBPNG_VER < 10700 */
+
+#ifdef __cplusplus
+#  define this not_the_cpp_this
+#  define new not_the_cpp_new
+#  define voidcast(type, value) static_cast<type>(value)
+#else
+#  define voidcast(type, value) (value)
+#endif /* __cplusplus */
+
+/* Unused formal parameter errors are removed using the following macro which is
+ * expected to have no bad effects on performance.
+ */
+#ifndef UNUSED
+#  if defined(__GNUC__) || defined(_MSC_VER)
+#     define UNUSED(param) (void)param;
+#  else
+#     define UNUSED(param)
+#  endif
+#endif
+
+/* Types of chunks not known to libpng */
+#define png_vpAg PNG_U32(118, 112, 65, 103)
+
 /* Chunk information */
 #define PNG_INFO_tEXt 0x10000000U
 #define PNG_INFO_iTXt 0x20000000U
@@ -139,23 +182,128 @@ static struct
    { "PLTE", PNG_INFO_PLTE, png_PLTE, 0, 0, ABSENT, 0 },
 
    /* Non-critical chunks that libpng handles */
-   { "bKGD", PNG_INFO_bKGD, png_bKGD, 0, 1,  START, 0 },
-   { "cHRM", PNG_INFO_cHRM, png_cHRM, 0, 1,  START, 0 },
-   { "gAMA", PNG_INFO_gAMA, png_gAMA, 0, 1,  START, 0 },
-   { "hIST", PNG_INFO_hIST, png_hIST, 0, 1, ABSENT, 0 },
-   { "iCCP", PNG_INFO_iCCP, png_iCCP, 0, 1, ABSENT, 0 },
-   { "iTXt", PNG_INFO_iTXt, png_iTXt, 0, 1, ABSENT, 0 },
-   { "oFFs", PNG_INFO_oFFs, png_oFFs, 0, 1,  START, 0 },
-   { "pCAL", PNG_INFO_pCAL, png_pCAL, 0, 1,  START, 0 },
-   { "pHYs", PNG_INFO_pHYs, png_pHYs, 0, 1,  START, 0 },
-   { "sBIT", PNG_INFO_sBIT, png_sBIT, 0, 1,  START, 0 },
-   { "sCAL", PNG_INFO_sCAL, png_sCAL, 0, 1,  START, 0 },
-   { "sPLT", PNG_INFO_sPLT, png_sPLT, 0, 1, ABSENT, 0 },
-   { "sRGB", PNG_INFO_sRGB, png_sRGB, 0, 1,  START, 0 },
-   { "tEXt", PNG_INFO_tEXt, png_tEXt, 0, 1,  START, 0 },
-   { "tIME", PNG_INFO_tIME, png_tIME, 0, 1,  START, 0 },
-   { "tRNS", PNG_INFO_tRNS, png_tRNS, 0, 0, ABSENT, 0 },
-   { "zTXt", PNG_INFO_zTXt, png_zTXt, 0, 1,    END, 0 },
+   /* This is a mess but it seems to be the only way to do it - there is no way
+    * to check for a definition outside a #if.
+    */
+   { "bKGD", PNG_INFO_bKGD, png_bKGD,
+#     ifdef PNG_READ_bKGD_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "cHRM", PNG_INFO_cHRM, png_cHRM,
+#     ifdef PNG_READ_cHRM_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "gAMA", PNG_INFO_gAMA, png_gAMA,
+#     ifdef PNG_READ_gAMA_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "hIST", PNG_INFO_hIST, png_hIST,
+#     ifdef PNG_READ_hIST_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "iCCP", PNG_INFO_iCCP, png_iCCP,
+#     ifdef PNG_READ_iCCP_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "iTXt", PNG_INFO_iTXt, png_iTXt,
+#     ifdef PNG_READ_iTXt_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "oFFs", PNG_INFO_oFFs, png_oFFs,
+#     ifdef PNG_READ_oFFs_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "pCAL", PNG_INFO_pCAL, png_pCAL,
+#     ifdef PNG_READ_pCAL_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "pHYs", PNG_INFO_pHYs, png_pHYs,
+#     ifdef PNG_READ_pHYs_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "sBIT", PNG_INFO_sBIT, png_sBIT,
+#     ifdef PNG_READ_sBIT_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "sCAL", PNG_INFO_sCAL, png_sCAL,
+#     ifdef PNG_READ_sCAL_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "sPLT", PNG_INFO_sPLT, png_sPLT,
+#     ifdef PNG_READ_sPLT_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1, ABSENT, 0 },
+   { "sRGB", PNG_INFO_sRGB, png_sRGB,
+#     ifdef PNG_READ_sRGB_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "tEXt", PNG_INFO_tEXt, png_tEXt,
+#     ifdef PNG_READ_tEXt_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "tIME", PNG_INFO_tIME, png_tIME,
+#     ifdef PNG_READ_tIME_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,  START, 0 },
+   { "tRNS", PNG_INFO_tRNS, png_tRNS,
+#     ifdef PNG_READ_tRNS_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      0, ABSENT, 0 },
+   { "zTXt", PNG_INFO_zTXt, png_zTXt,
+#     ifdef PNG_READ_zTXt_SUPPORTED
+         0,
+#     else
+         1,
+#     endif
+      1,    END, 0 },
 
    /* No libpng handling */
    { "sTER", PNG_INFO_sTER, png_sTER, 1, 1,  START, 0 },
@@ -212,14 +360,16 @@ find_by_flag(png_uint_32 flag)
 static int
 ancillary(const char *name)
 {
-   return PNG_CHUNK_ANCILLARY(PNG_CHUNK(name[0], name[1], name[2], name[3]));
+   return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 }
 
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static int
 ancillaryb(const png_byte *name)
 {
-   return PNG_CHUNK_ANCILLARY(PNG_CHUNK(name[0], name[1], name[2], name[3]));
+   return PNG_CHUNK_ANCILLARY(PNG_U32(name[0], name[1], name[2], name[3]));
 }
+#endif
 
 /* Type of an error_ptr */
 typedef struct
@@ -227,8 +377,11 @@ typedef struct
    jmp_buf     error_return;
    png_structp png_ptr;
    png_infop   info_ptr, end_ptr;
+   png_uint_32 before_IDAT;
+   png_uint_32 after_IDAT;
    int         error_count;
    int         warning_count;
+   int         keep; /* the default value */
    const char *program;
    const char *file;
    const char *test;
@@ -261,9 +414,6 @@ clean_display(display *d)
          d->test);
       exit(1);
    }
-
-   /* Invalidate the test */
-   d->test = init;
 }
 
 PNG_FUNCTION(void, display_exit, (display *d), static PNG_NORETURN)
@@ -289,7 +439,7 @@ display_rc(const display *d, int strict)
 }
 
 /* libpng error and warning callbacks */
-PNG_FUNCTION(void, error, (png_structp png_ptr, const char *message),
+PNG_FUNCTION(void, (PNGCBAPI error), (png_structp png_ptr, const char *message),
    static PNG_NORETURN)
 {
    display *d = (display*)png_get_error_ptr(png_ptr);
@@ -298,7 +448,7 @@ PNG_FUNCTION(void, error, (png_structp png_ptr, const char *message),
    display_exit(d);
 }
 
-static void
+static void PNGCBAPI
 warning(png_structp png_ptr, const char *message)
 {
    display *d = (display*)png_get_error_ptr(png_ptr);
@@ -339,11 +489,88 @@ get_valid(display *d, png_infop info_ptr)
    return flags;
 }
 
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+static int PNGCBAPI
+read_callback(png_structp pp, png_unknown_chunkp pc)
+{
+   /* This function mimics the behavior of png_set_keep_unknown_chunks by
+    * returning '0' to keep the chunk and '1' to discard it.
+    */
+   display *d = voidcast(display*, png_get_user_chunk_ptr(pp));
+   int chunk = findb(pc->name);
+   int keep, discard;
+
+   if (chunk < 0) /* not one in our list, so not a known chunk */
+      keep = d->keep;
+
+   else
+   {
+      keep = chunk_info[chunk].keep;
+      if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
+      {
+         /* See the comments in png.h - use the default for unknown chunks,
+          * do not keep known chunks.
+          */
+         if (chunk_info[chunk].unknown)
+            keep = d->keep;
+
+         else
+            keep = PNG_HANDLE_CHUNK_NEVER;
+      }
+   }
+
+   switch (keep)
+   {
+      default:
+         fprintf(stderr, "%s(%s): %d: unrecognized chunk option\n", d->file,
+            d->test, chunk_info[chunk].keep);
+         display_exit(d);
+
+      case PNG_HANDLE_CHUNK_AS_DEFAULT:
+      case PNG_HANDLE_CHUNK_NEVER:
+         discard = 1/*handled; discard*/;
+         break;
+
+      case PNG_HANDLE_CHUNK_IF_SAFE:
+      case PNG_HANDLE_CHUNK_ALWAYS:
+         discard = 0/*not handled; keep*/;
+         break;
+   }
+
+   /* Also store information about this chunk in the display, the relevant flag
+    * is set if the chunk is to be kept ('not handled'.)
+    */
+   if (chunk >= 0) if (!discard) /* stupidity to stop a GCC warning */
+   {
+      png_uint_32 flag = chunk_info[chunk].flag;
+
+      if (pc->location & PNG_AFTER_IDAT)
+         d->after_IDAT |= flag;
+
+      else
+         d->before_IDAT |= flag;
+   }
+
+   /* However if there is no support to store unknown chunks don't ask libpng to
+    * do it; there will be an png_error.
+    */
+#  ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+      return discard;
+#  else
+      return 1; /*handled; discard*/
+#  endif
+}
+#endif /* READ_USER_CHUNKS_SUPPORTED */
+
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static png_uint_32
-get_unknown(display *d, int def, png_infop info_ptr)
+get_unknown(display *d, png_infop info_ptr, int after_IDAT)
 {
    /* Create corresponding 'unknown' flags */
    png_uint_32 flags = 0;
+
+   UNUSED(after_IDAT)
+
    {
       png_unknown_chunkp unknown;
       int num_unknown = png_get_unknown_chunks(d->png_ptr, info_ptr, &unknown);
@@ -353,16 +580,16 @@ get_unknown(display *d, int def, png_infop info_ptr)
          int chunk = findb(unknown[num_unknown].name);
 
          /* Chunks not known to pngunknown must be validated here; since they
-          * must also be unknown to libpng the 'def' behavior should have been
-          * used.
+          * must also be unknown to libpng the 'display->keep' behavior should
+          * have been used.
           */
-         if (chunk < 0) switch (def)
+         if (chunk < 0) switch (d->keep)
          {
             default: /* impossible */
             case PNG_HANDLE_CHUNK_AS_DEFAULT:
             case PNG_HANDLE_CHUNK_NEVER:
                fprintf(stderr, "%s(%s): %s: %s: unknown chunk saved\n",
-                  d->file, d->test, def ? "discard" : "default",
+                  d->file, d->test, d->keep ? "discard" : "default",
                   unknown[num_unknown].name);
                ++(d->error_count);
                break;
@@ -388,14 +615,39 @@ get_unknown(display *d, int def, png_infop info_ptr)
 
    return flags;
 }
+#else
+static png_uint_32
+get_unknown(display *d, png_infop info_ptr, int after_IDAT)
+   /* Otherwise this will return the cached values set by any user callback */
+{
+   UNUSED(info_ptr);
+
+   if (after_IDAT)
+      return d->after_IDAT;
+
+   else
+      return d->before_IDAT;
+}
+
+#  ifndef PNG_READ_USER_CHUNKS_SUPPORTED
+      /* The #defines above should mean this is never reached, it's just here as
+       * a check to ensure the logic is correct.
+       */
+#     error No store support and no user chunk support, this will not work
+#  endif
+#endif
 
 static int
 check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
-   display *d)
+   display *d, int set_callback)
 {
-   int i, def = PNG_HANDLE_CHUNK_AS_DEFAULT, npasses, ipass;
+   int i, npasses, ipass;
    png_uint_32 height;
 
+   d->keep = PNG_HANDLE_CHUNK_AS_DEFAULT;
+   d->before_IDAT = 0;
+   d->after_IDAT = 0;
+
    /* Some of these errors are permanently fatal and cause an exit here, others
     * are per-test and cause an error return.
     */
@@ -421,6 +673,16 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
 
    png_init_io(d->png_ptr, fp);
 
+#  ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+      /* This is only done if requested by the caller; it interferes with the
+       * standard store/save mechanism.
+       */
+      if (set_callback)
+         png_set_read_user_chunk_fn(d->png_ptr, d, read_callback);
+#  else
+      UNUSED(set_callback)
+#  endif
+
    /* Handle each argument in turn; multiple settings are possible for the same
     * chunk and multiple calls will occur (the last one should override all
     * preceding ones).
@@ -460,13 +722,11 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
                    * in this case, so we just check the arguments!  This could
                    * be improved in the future by using the read callback.
                    */
-#                 ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
-                     png_byte name[5];
+                  png_byte name[5];
 
-                     memcpy(name, chunk_info[chunk].name, 5);
-                     png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
-                     chunk_info[chunk].keep = option;
-#                 endif
+                  memcpy(name, chunk_info[chunk].name, 5);
+                  png_set_keep_unknown_chunks(d->png_ptr, option, name, 1);
+                  chunk_info[chunk].keep = option;
                   continue;
                }
 
@@ -475,10 +735,8 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
             case 7: /* default */
                if (memcmp(argv[i], "default", 7) == 0)
                {
-#                 ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
-                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
-#                 endif
-                  def = option;
+                  png_set_keep_unknown_chunks(d->png_ptr, option, NULL, 0);
+                  d->keep = option;
                   continue;
                }
 
@@ -487,14 +745,12 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
             case 3: /* all */
                if (memcmp(argv[i], "all", 3) == 0)
                {
-#                 ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
-                     png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
-                     def = option;
+                  png_set_keep_unknown_chunks(d->png_ptr, option, NULL, -1);
+                  d->keep = option;
 
-                     for (chunk = 0; chunk < NINFO; ++chunk)
-                        if (chunk_info[chunk].all)
-                           chunk_info[chunk].keep = option;
-#                 endif
+                  for (chunk = 0; chunk < NINFO; ++chunk)
+                     if (chunk_info[chunk].all)
+                        chunk_info[chunk].keep = option;
                   continue;
                }
 
@@ -568,18 +824,18 @@ check(FILE *fp, int argc, const char **argv, png_uint_32p flags/*out*/,
    png_read_end(d->png_ptr, d->end_ptr);
 
    flags[0] = get_valid(d, d->info_ptr);
-   flags[1] = get_unknown(d, def, d->info_ptr);
+   flags[1] = get_unknown(d, d->info_ptr, 0/*before IDAT*/);
 
    /* Only png_read_png sets PNG_INFO_IDAT! */
    flags[chunk_info[0/*IDAT*/].keep != PNG_HANDLE_CHUNK_AS_DEFAULT] |=
       PNG_INFO_IDAT;
 
    flags[2] = get_valid(d, d->end_ptr);
-   flags[3] = get_unknown(d, def, d->end_ptr);
+   flags[3] = get_unknown(d, d->end_ptr, 1/*after IDAT*/);
 
    clean_display(d);
 
-   return def;
+   return d->keep;
 }
 
 static void
@@ -600,7 +856,7 @@ check_error(display *d, png_uint_32 flags, const char *message)
 
 static void
 check_handling(display *d, int def, png_uint_32 chunks, png_uint_32 known,
-   png_uint_32 unknown, const char *position)
+   png_uint_32 unknown, const char *position, int set_callback)
 {
    while (chunks)
    {
@@ -707,8 +963,9 @@ check_handling(display *d, int def, png_uint_32 chunks, png_uint_32 known,
       if (errorx != NULL)
       {
          ++(d->error_count);
-         fprintf(stderr, "%s(%s): %s %s %s: %s\n",
-            d->file, d->test, type, chunk_info[i].name, position, errorx);
+         fprintf(stderr, "%s(%s%s): %s %s %s: %s\n", d->file, d->test,
+            set_callback ? ",callback" : "",
+            type, chunk_info[i].name, position, errorx);
       }
 
       chunks &= ~flag;
@@ -717,7 +974,7 @@ check_handling(display *d, int def, png_uint_32 chunks, png_uint_32 known,
 
 static void
 perform_one_test(FILE *fp, int argc, const char **argv,
-   png_uint_32 *default_flags, display *d)
+   png_uint_32 *default_flags, display *d, int set_callback)
 {
    int def;
    png_uint_32 flags[2][4];
@@ -726,7 +983,7 @@ perform_one_test(FILE *fp, int argc, const char **argv,
    clear_keep();
    memcpy(flags[0], default_flags, sizeof flags[0]);
 
-   def = check(fp, argc, argv, flags[1], d);
+   def = check(fp, argc, argv, flags[1], d, set_callback);
 
    /* Chunks should either be known or unknown, never both and this should apply
     * whether the chunk is before or after the IDAT (actually, the app can
@@ -761,9 +1018,9 @@ perform_one_test(FILE *fp, int argc, const char **argv,
     * it or not.
     */
    check_handling(d, def, flags[0][0] | flags[0][1], flags[1][0], flags[1][1],
-      "before IDAT");
+      "before IDAT", set_callback);
    check_handling(d, def, flags[0][2] | flags[0][3], flags[1][2], flags[1][3],
-      "after IDAT");
+      "after IDAT", set_callback);
 }
 
 static void
@@ -773,7 +1030,12 @@ perform_one_test_safe(FILE *fp, int argc, const char **argv,
    if (setjmp(d->error_return) == 0)
    {
       d->test = test; /* allow use of d->error_return */
-      perform_one_test(fp, argc, argv, default_flags, d);
+#     ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+         perform_one_test(fp, argc, argv, default_flags, d, 0);
+#     endif
+#     ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+         perform_one_test(fp, argc, argv, default_flags, d, 1);
+#     endif
       d->test = init; /* prevent use of d->error_return */
    }
 }
@@ -797,7 +1059,7 @@ usage(const char *program, const char *reason)
    fprintf(stderr, "pngunknown: %s: usage:\n %s [--strict] "
       "--default|{(CHNK|default|all)=(default|discard|if-safe|save)} "
       "testfile.png\n", reason, program);
-   exit(2);
+   exit(99);
 }
 
 int
@@ -845,11 +1107,6 @@ main(int argc, const char **argv)
    else if (default_tests) if (argc != 1)
       usage(d.program, "extra arguments");
 
-#  ifndef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
-      fprintf(stderr, "%s: warning: no 'save' support so arguments ignored\n",
-         d.program);
-#  endif
-
    /* The name of the test file is the last argument; remove it. */
    d.file = argv[--argc];
 
@@ -857,24 +1114,40 @@ main(int argc, const char **argv)
    if (fp == NULL)
    {
       perror(d.file);
-      exit(2);
+      exit(99);
    }
 
    /* First find all the chunks, known and unknown, in the test file, a failure
     * here aborts the whole test.
+    *
+    * If 'save' is supported then the normal saving method should happen,
+    * otherwise if 'read' is supported then the read callback will do the
+    * same thing.  If both are supported the 'read' callback won't be
+    * instantiated by default.  If 'save' is *not* supported then a user
+    * callback is required even though we can call png_get_unknown_chunks.
     */
-   if (check(fp, 1, &count_argv, default_flags, &d) !=
-      PNG_HANDLE_CHUNK_ALWAYS)
+   if (check(fp, 1, &count_argv, default_flags, &d,
+#     ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+         0
+#     else
+         1
+#     endif
+      ) != PNG_HANDLE_CHUNK_ALWAYS)
    {
       fprintf(stderr, "%s: %s: internal error\n", d.program, d.file);
-      exit(3);
+      exit(99);
    }
 
    /* Now find what the various supplied options cause to change: */
    if (!default_tests)
    {
       d.test = cmd; /* acts as a flag to say exit, do not longjmp */
-      perform_one_test(fp, argc, argv, default_flags, &d);
+#     ifdef PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
+         perform_one_test(fp, argc, argv, default_flags, &d, 0);
+#     endif
+#     ifdef PNG_READ_USER_CHUNKS_SUPPORTED
+         perform_one_test(fp, argc, argv, default_flags, &d, 1);
+#     endif
       d.test = init;
    }
 
@@ -932,14 +1205,14 @@ main(int argc, const char **argv)
             if (fclose(fsuccess) || err)
             {
                fprintf(stderr, "%s: write failed\n", touch_file);
-               exit(1);
+               exit(99);
             }
          }
 
          else
          {
             fprintf(stderr, "%s: open failed\n", touch_file);
-            exit(1);
+            exit(99);
          }
       }
 
@@ -949,12 +1222,24 @@ main(int argc, const char **argv)
    return 1;
 }
 
-#else
+#else /* !(READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS) */
 int
 main(void)
 {
    fprintf(stderr,
-   " test ignored because libpng was not built with unknown chunk support\n");
-   return 0;
+      " test ignored: no support to find out about unknown chunks\n");
+   /* So the test is skipped: */
+   return 77;
 }
-#endif
+#endif /* READ_USER_CHUNKS || SAVE_UNKNOWN_CHUNKS */
+
+#else /* !(SET_UNKNOWN_CHUNKS && READ) */
+int
+main(void)
+{
+   fprintf(stderr,
+      " test ignored: no support to modify unknown chunk handling\n");
+   /* So the test is skipped: */
+   return 77;
+}
+#endif /* SET_UNKNOWN_CHUNKS && READ*/

contrib/libtests/pngvalid.c

@@ -1,8 +1,8 @@
 
 /* pngvalid.c - validate libpng by constructing then reading png files.
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Copyright (c) 2014 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
  * This code is released under the libpng license.
@@ -34,18 +34,44 @@
 #  include <fenv.h>
 #endif
 
+#ifndef FE_DIVBYZERO
+#  define FE_DIVBYZERO 0
+#endif
+#ifndef FE_INVALID
+#  define FE_INVALID 0
+#endif
+#ifndef FE_OVERFLOW
+#  define FE_OVERFLOW 0
+#endif
+
 /* Define the following to use this test against your installed libpng, rather
  * than the one being built here:
  */
 #ifdef PNG_FREESTANDING_TESTS
 #  include <png.h>
-#  include <zlib.h>   /* For crc32 */
 #else
 #  include "../../png.h"
-#  include PNG_ZLIB_HEADER
 #endif
 
-#ifdef PNG_WRITE_SUPPORTED /* else pngvalid can do nothing */
+#ifdef PNG_ZLIB_HEADER
+#  include PNG_ZLIB_HEADER
+#else
+#  include <zlib.h>   /* For crc32 */
+#endif
+
+/* 1.6.1 added support for the configure test harness, which uses 77 to indicate
+ * a skipped test, in earlier versions we need to succeed on a skipped test, so:
+ */
+#if PNG_LIBPNG_VER < 10601
+#  define SKIP 0
+#else
+#  define SKIP 77
+#endif
+
+/* pngvalid requires write support and one of the fixed or floating point APIs.
+ */
+#if defined(PNG_WRITE_SUPPORTED) &&\
+   (defined(PNG_FIXED_POINT_SUPPORTED) || defined(PNG_FLOATING_POINT_SUPPORTED))
 
 #if PNG_LIBPNG_VER < 10500
 /* This deliberately lacks the PNG_CONST. */
@@ -131,6 +157,13 @@ define_exception_type(struct png_store*);
    &(ps)->exception_context
 #define context(ps,fault) anon_context(ps); png_store *fault
 
+/* This macro returns the number of elements in an array as an (unsigned int),
+ * it is necessary to avoid the inability of certain versions of GCC to use
+ * the value of a compile-time constant when performing range checks.  It must
+ * be passed an array name.
+ */
+#define ARRAY_SIZE(a) ((unsigned int)((sizeof (a))/(sizeof (a)[0])))
+
 /******************************* UTILITIES ************************************/
 /* Error handling is particularly problematic in production code - error
  * handlers often themselves have bugs which lead to programs that detect
@@ -370,9 +403,9 @@ next_format(png_bytep colour_type, png_bytep bit_depth,
 
    /* Palette images are restricted to 8 bit depth */
    if (*bit_depth <= 8
-#     ifdef DO_16BIT
+#ifdef DO_16BIT
          || (*colour_type != 3 && *bit_depth <= 16)
-#     endif
+#endif
       )
       return 1;
 
@@ -621,7 +654,12 @@ typedef struct png_store
    unsigned int       validated :1;   /* used as a temporary flag */
    int                nerrors;
    int                nwarnings;
-   char               test[128]; /* Name of test */
+   int                noptions;       /* number of options below: */
+   struct {
+      unsigned char   option;         /* option number, 0..30 */
+      unsigned char   setting;        /* setting (unset,invalid,on,off) */
+   }                  options[16];
+   char               test[128];      /* Name of test */
    char               error[256];
 
    /* Read fields */
@@ -665,7 +703,7 @@ static png_uint_32
 random_32(void)
 {
 
-   for(;;)
+   for (;;)
    {
       png_byte mark[4];
       png_uint_32 result;
@@ -722,6 +760,7 @@ store_init(png_store* ps)
    ps->new.prev = NULL;
    ps->palette = NULL;
    ps->npalette = 0;
+   ps->noptions = 0;
 }
 
 static void
@@ -899,7 +938,7 @@ internal_error(png_store *ps, png_const_charp message)
 #endif /* PNG_READ_SUPPORTED */
 
 /* Functions to use as PNG callbacks. */
-static void
+static void PNGCBAPI
 store_error(png_structp ppIn, png_const_charp message) /* PNG_NORETURN */
 {
    png_const_structp pp = ppIn;
@@ -915,7 +954,7 @@ store_error(png_structp ppIn, png_const_charp message) /* PNG_NORETURN */
    }
 }
 
-static void
+static void PNGCBAPI
 store_warning(png_structp ppIn, png_const_charp message)
 {
    png_const_structp pp = ppIn;
@@ -1066,7 +1105,7 @@ store_image_check(PNG_CONST png_store* ps, png_const_structp pp, int iImage)
 }
 #endif /* PNG_READ_SUPPORTED */
 
-static void
+static void PNGCBAPI
 store_write(png_structp ppIn, png_bytep pb, png_size_t st)
 {
    png_const_structp pp = ppIn;
@@ -1094,7 +1133,7 @@ store_write(png_structp ppIn, png_bytep pb, png_size_t st)
    }
 }
 
-static void
+static void PNGCBAPI
 store_flush(png_structp ppIn)
 {
    UNUSED(ppIn) /*DOES NOTHING*/
@@ -1188,7 +1227,7 @@ store_read_imp(png_store *ps, png_bytep pb, png_size_t st)
    }
 }
 
-static void
+static void PNGCBAPI
 store_read(png_structp ppIn, png_bytep pb, png_size_t st)
 {
    png_const_structp pp = ppIn;
@@ -1262,6 +1301,7 @@ store_current_palette(png_store *ps, int *npalette)
 #endif /* PNG_READ_SUPPORTED */
 
 /***************************** MEMORY MANAGEMENT*** ***************************/
+#ifdef PNG_USER_MEM_SUPPORTED
 /* A store_memory is simply the header for an allocated block of memory.  The
  * pointer returned to libpng is just after the end of the header block, the
  * allocated memory is followed by a second copy of the 'mark'.
@@ -1380,7 +1420,7 @@ store_pool_delete(png_store *ps, store_pool *pool)
 }
 
 /* The memory callbacks: */
-static png_voidp
+static png_voidp PNGCBAPI
 store_malloc(png_structp ppIn, png_alloc_size_t cb)
 {
    png_const_structp pp = ppIn;
@@ -1429,7 +1469,7 @@ store_malloc(png_structp ppIn, png_alloc_size_t cb)
    return new;
 }
 
-static void
+static void PNGCBAPI
 store_free(png_structp ppIn, png_voidp memory)
 {
    png_const_structp pp = ppIn;
@@ -1462,6 +1502,7 @@ store_free(png_structp ppIn, png_voidp memory)
    this->next = NULL;
    store_memory_free(pp, pool, this);
 }
+#endif /* PNG_USER_MEM_SUPPORTED */
 
 /* Setup functions. */
 /* Cleanup when aborting a write or after storing the new file. */
@@ -1487,7 +1528,9 @@ store_write_reset(png_store *ps)
    /* And make sure that all the memory has been freed - this will output
     * spurious errors in the case of memory corruption above, but this is safe.
     */
-   store_pool_delete(ps, &ps->write_memory_pool);
+#  ifdef PNG_USER_MEM_SUPPORTED
+      store_pool_delete(ps, &ps->write_memory_pool);
+#  endif
 
    store_freenew(ps);
 }
@@ -1511,18 +1554,32 @@ set_store_for_write(png_store *ps, png_infopp ppi,
       store_write_reset(ps);
       safecat(ps->wname, sizeof ps->wname, 0, name);
 
-      /* Don't do the slow memory checks if doing a speed test. */
-      if (ps->speed)
+      /* Don't do the slow memory checks if doing a speed test, also if user
+       * memory is not supported we can't do it anyway.
+       */
+#     ifdef PNG_USER_MEM_SUPPORTED
+         if (!ps->speed)
+            ps->pwrite = png_create_write_struct_2(PNG_LIBPNG_VER_STRING,
+               ps, store_error, store_warning, &ps->write_memory_pool,
+               store_malloc, store_free);
+
+         else
+#     endif
          ps->pwrite = png_create_write_struct(PNG_LIBPNG_VER_STRING,
             ps, store_error, store_warning);
 
-      else
-         ps->pwrite = png_create_write_struct_2(PNG_LIBPNG_VER_STRING,
-            ps, store_error, store_warning, &ps->write_memory_pool,
-            store_malloc, store_free);
-
       png_set_write_fn(ps->pwrite, ps, store_write, store_flush);
 
+#     ifdef PNG_SET_OPTION_SUPPORTED
+         {
+            int opt;
+            for (opt=0; opt<ps->noptions; ++opt)
+               if (png_set_option(ps->pwrite, ps->options[opt].option,
+                  ps->options[opt].setting) == PNG_OPTION_INVALID)
+                  png_error(ps->pwrite, "png option invalid");
+         }
+#     endif
+
       if (ppi != NULL)
          *ppi = ps->piwrite = png_create_info_struct(ps->pwrite);
    }
@@ -1558,8 +1615,10 @@ store_read_reset(png_store *ps)
       }
 #  endif
 
-   /* Always do this to be safe. */
-   store_pool_delete(ps, &ps->read_memory_pool);
+#  ifdef PNG_USER_MEM_SUPPORTED
+      /* Always do this to be safe. */
+      store_pool_delete(ps, &ps->read_memory_pool);
+#  endif
 
    ps->current = NULL;
    ps->next = NULL;
@@ -1586,14 +1645,14 @@ store_read_set(png_store *ps, png_uint_32 id)
       pf = pf->next;
    }
 
-      {
+   {
       size_t pos;
       char msg[FILE_NAME_SIZE+64];
 
       pos = standard_name_from_id(msg, sizeof msg, 0, id);
       pos = safecat(msg, sizeof msg, pos, ": file not found");
       png_error(ps->pread, msg);
-      }
+   }
 }
 
 /* The main interface for reading a saved file - pass the id number of the file
@@ -1619,14 +1678,16 @@ set_store_for_read(png_store *ps, png_infopp ppi, png_uint_32 id,
     * However, given that store_error works correctly in these circumstances
     * we don't ever expect NULL in this program.
     */
-   if (ps->speed)
-      ps->pread = png_create_read_struct(PNG_LIBPNG_VER_STRING, ps,
-          store_error, store_warning);
+#  ifdef PNG_USER_MEM_SUPPORTED
+      if (!ps->speed)
+         ps->pread = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, ps,
+             store_error, store_warning, &ps->read_memory_pool, store_malloc,
+             store_free);
 
-   else
-      ps->pread = png_create_read_struct_2(PNG_LIBPNG_VER_STRING, ps,
-          store_error, store_warning, &ps->read_memory_pool, store_malloc,
-          store_free);
+      else
+#  endif
+   ps->pread = png_create_read_struct(PNG_LIBPNG_VER_STRING, ps, store_error,
+      store_warning);
 
    if (ps->pread == NULL)
    {
@@ -1638,6 +1699,16 @@ set_store_for_read(png_store *ps, png_infopp ppi, png_uint_32 id,
       Throw ps;
    }
 
+#  ifdef PNG_SET_OPTION_SUPPORTED
+      {
+         int opt;
+         for (opt=0; opt<ps->noptions; ++opt)
+            if (png_set_option(ps->pread, ps->options[opt].option,
+               ps->options[opt].setting) == PNG_OPTION_INVALID)
+                  png_error(ps->pread, "png option invalid");
+      }
+#  endif
+
    store_read_set(ps, id);
 
    if (ppi != NULL)
@@ -1919,7 +1990,7 @@ typedef struct png_modifier
 
 /* This returns true if the test should be stopped now because it has already
  * failed and it is running silently.
- */
+  */
 static int fail(png_modifier *pm)
 {
    return !pm->log && !pm->this.verbose && (pm->this.nerrors > 0 ||
@@ -2617,7 +2688,7 @@ modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
 }
 
 /* The callback: */
-static void
+static void PNGCBAPI
 modifier_read(png_structp ppIn, png_bytep pb, png_size_t st)
 {
    png_const_structp pp = ppIn;
@@ -2937,6 +3008,12 @@ sbit_modification_init(sbit_modification *me, png_modifier *pm, png_byte sbit)
  * height of 16 rows.  The width and height are stored in the FILEID and, being
  * non-zero, indicate a size file.
  *
+ * Because the PNG filter code is typically the largest CPU consumer within
+ * libpng itself there is a tendency to attempt to optimize it.  This results in
+ * special case code which needs to be validated.  To cause this to happen the
+ * 'size' images are made to use each possible filter, in so far as this is
+ * possible for smaller images.
+ *
  * For palette image (colour type 3) multiple transform images are stored with
  * the same bit depth to allow testing of more colour combinations -
  * particularly important for testing the gamma code because libpng uses a
@@ -3095,8 +3172,10 @@ init_standard_palette(png_store *ps, png_structp pp, png_infop pi, int npalette,
       for (; i<256; ++i)
          tRNS[i] = 24;
 
-      if (j > 0)
-         png_set_tRNS(pp, pi, tRNS, j, 0/*color*/);
+#ifdef PNG_WRITE_tRNS_SUPPORTED
+         if (j > 0)
+            png_set_tRNS(pp, pi, tRNS, j, 0/*color*/);
+#endif
    }
 }
 
@@ -3342,6 +3421,31 @@ transform_row(png_const_structp pp, png_byte buffer[TRANSFORM_ROWMAX],
  */
 #define DEPTH(bd) ((png_byte)(1U << (bd)))
 
+/* This is just a helper for compiling on minimal systems with no write
+ * interlacing support.  If there is no write interlacing we can't generate test
+ * cases with interlace:
+ */
+#ifdef PNG_WRITE_INTERLACING_SUPPORTED
+#  define INTERLACE_LAST PNG_INTERLACE_LAST
+#  define check_interlace_type(type) ((void)(type))
+#else
+#  define INTERLACE_LAST (PNG_INTERLACE_NONE+1)
+#  define png_set_interlace_handling(a) (1)
+
+static void
+check_interlace_type(int PNG_CONST interlace_type)
+{
+   if (interlace_type != PNG_INTERLACE_NONE)
+   {
+      /* This is an internal error - --interlace tests should be skipped, not
+       * attempted.
+       */
+      fprintf(stderr, "pngvalid: no interlace support\n");
+      exit(99);
+   }
+}
+#endif
+
 /* Make a standardized image given a an image colour type, bit depth and
  * interlace type.  The standard images have a very restricted range of
  * rows and heights and are used for testing transforms rather than image
@@ -3355,6 +3459,8 @@ make_transform_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
 {
    context(ps, fault);
 
+   check_interlace_type(interlace_type);
+
    Try
    {
       png_infop pi;
@@ -3496,7 +3602,7 @@ make_transform_images(png_store *ps)
       int interlace_type;
 
       for (interlace_type = PNG_INTERLACE_NONE;
-           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)
+           interlace_type < INTERLACE_LAST; ++interlace_type)
       {
          char name[FILE_NAME_SIZE];
 
@@ -3586,6 +3692,12 @@ make_size_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
 {
    context(ps, fault);
 
+   /* At present libpng does not support the write of an interlaced image unless
+    * PNG_WRITE_INTERLACING_SUPPORTED, even with do_interlace so the code here
+    * does the pixel interlace itself, so:
+    */
+   check_interlace_type(interlace_type);
+
    Try
    {
       png_infop pi;
@@ -3652,6 +3764,9 @@ make_size_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
          int npasses = npasses_from_interlace_type(pp, interlace_type);
          png_uint_32 y;
          int pass;
+#        ifdef PNG_WRITE_FILTER_SUPPORTED
+            int nfilter = PNG_FILTER_VALUE_LAST;
+#        endif
          png_byte image[16][SIZE_ROWMAX];
 
          /* To help consistent error detection make the parts of this buffer
@@ -3705,7 +3820,24 @@ make_size_image(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type,
                      continue;
                }
 
-               /* Only get to here if the row has some pixels in it. */
+#           ifdef PNG_WRITE_FILTER_SUPPORTED
+               /* Only get to here if the row has some pixels in it, set the
+                * filters to 'all' for the very first row and thereafter to a
+                * single filter.  It isn't well documented, but png_set_filter
+                * does accept a filter number (per the spec) as well as a bit
+                * mask.
+                *
+                * The apparent wackiness of decrementing nfilter rather than
+                * incrementing is so that Paeth gets used in all images bigger
+                * than 1 row - it's the tricky one.
+                */
+               png_set_filter(pp, 0/*method*/,
+                  nfilter >= PNG_FILTER_VALUE_LAST ? PNG_ALL_FILTERS : nfilter);
+
+               if (nfilter-- == 0)
+                  nfilter = PNG_FILTER_VALUE_LAST-1;
+#           endif
+
                png_write_row(pp, row);
             }
          }
@@ -3772,10 +3904,12 @@ make_size(png_store* PNG_CONST ps, png_byte PNG_CONST colour_type, int bdlo,
                width, height, 0);
             make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_NONE,
                width, height, 1);
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
             make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7,
                width, height, 0);
             make_size_image(ps, colour_type, DEPTH(bdlo), PNG_INTERLACE_ADAM7,
                width, height, 1);
+#        endif
          }
       }
    }
@@ -3866,6 +4000,8 @@ make_error(png_store* volatile psIn, png_byte PNG_CONST colour_type,
 
    context(ps, fault);
 
+   check_interlace_type(interlace_type);
+
    Try
    {
       png_structp pp;
@@ -3969,7 +4105,7 @@ make_errors(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
       int interlace_type;
 
       for (interlace_type = PNG_INTERLACE_NONE;
-           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)
+           interlace_type < INTERLACE_LAST; ++interlace_type)
       {
          unsigned int test;
          char name[FILE_NAME_SIZE];
@@ -3977,7 +4113,7 @@ make_errors(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
          standard_name(name, sizeof name, 0, colour_type, 1<<bdlo, 0,
             interlace_type, 0, 0, 0);
 
-         for (test=0; test<(sizeof error_test)/(sizeof error_test[0]); ++test)
+         for (test=0; test<ARRAY_SIZE(error_test); ++test)
          {
             make_error(&pm->this, colour_type, DEPTH(bdlo), interlace_type,
                test, name);
@@ -3990,7 +4126,7 @@ make_errors(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
 
    return 1; /* keep going */
 }
-#endif
+#endif /* PNG_WARNINGS_SUPPORTED */
 
 static void
 perform_error_test(png_modifier *pm)
@@ -4167,6 +4303,7 @@ standard_display_init(standard_display *dp, png_store* ps, png_uint_32 id,
       dp->red_sBIT = dp->blue_sBIT = dp->green_sBIT = dp->alpha_sBIT =
          dp->bit_depth;
    dp->interlace_type = INTERLACE_FROM_ID(id);
+   check_interlace_type(dp->interlace_type);
    dp->id = id;
    /* All the rest are filled in after the read_info: */
    dp->w = 0;
@@ -4555,7 +4692,7 @@ standard_info_imp(standard_display *dp, png_structp pp, png_infop pi,
    standard_info_part2(dp, pp, pi, nImages);
 }
 
-static void
+static void PNGCBAPI
 standard_info(png_structp pp, png_infop pi)
 {
    standard_display *dp = voidcast(standard_display*,
@@ -4567,7 +4704,7 @@ standard_info(png_structp pp, png_infop pi)
    standard_info_imp(dp, pp, pi, 1 /*only one image*/);
 }
 
-static void
+static void PNGCBAPI
 progressive_row(png_structp ppIn, png_bytep new_row, png_uint_32 y, int pass)
 {
    png_const_structp pp = ppIn;
@@ -4776,7 +4913,7 @@ standard_check_text(png_const_structp pp, png_const_textp tp,
 
 static void
 standard_text_validate(standard_display *dp, png_const_structp pp,
-   png_infop pi)
+   png_infop pi, int check_end)
 {
    png_textp tp = NULL;
    png_uint_32 num_text = png_get_text(pp, pi, &tp, NULL);
@@ -4784,7 +4921,13 @@ standard_text_validate(standard_display *dp, png_const_structp pp,
    if (num_text == 2 && tp != NULL)
    {
       standard_check_text(pp, tp, "image name", dp->ps->current->name);
-      standard_check_text(pp, tp+1, "end marker", "end");
+
+      /* This exists because prior to 1.5.18 the progressive reader left the
+       * png_struct z_stream unreset at the end of the image, so subsequent
+       * attempts to use it simply returns Z_STREAM_END.
+       */
+      if (check_end)
+         standard_check_text(pp, tp+1, "end marker", "end");
    }
 
    else
@@ -4797,7 +4940,7 @@ standard_text_validate(standard_display *dp, png_const_structp pp,
    }
 }
 #else
-#  define standard_text_validate(dp,pp,pi) ((void)0)
+#  define standard_text_validate(dp,pp,pi,check_end) ((void)0)
 #endif
 
 static void
@@ -4875,7 +5018,7 @@ standard_image_validate(standard_display *dp, png_const_structp pp, int iImage,
    dp->ps->validated = 1;
 }
 
-static void
+static void PNGCBAPI
 standard_end(png_structp ppIn, png_infop pi)
 {
    png_const_structp pp = ppIn;
@@ -4887,7 +5030,8 @@ standard_end(png_structp ppIn, png_infop pi)
    /* Validate the image - progressive reading only produces one variant for
     * interlaced images.
     */
-   standard_text_validate(dp, pp, pi);
+   standard_text_validate(dp, pp, pi,
+      PNG_LIBPNG_VER >= 10518/*check_end: see comments above*/);
    standard_image_validate(dp, pp, 0, -1);
 }
 
@@ -4958,7 +5102,7 @@ standard_test(png_store* PNG_CONST psIn, png_uint_32 PNG_CONST id,
              */
             if (!d.speed)
             {
-               standard_text_validate(&d, pp, pi);
+               standard_text_validate(&d, pp, pi, 1/*check_end*/);
                standard_image_validate(&d, pp, 0, 1);
             }
             else
@@ -4989,7 +5133,7 @@ test_standard(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
       int interlace_type;
 
       for (interlace_type = PNG_INTERLACE_NONE;
-           interlace_type < PNG_INTERLACE_LAST; ++interlace_type)
+           interlace_type < INTERLACE_LAST; ++interlace_type)
       {
          standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
             interlace_type, 0, 0, 0), 0/*do_interlace*/, pm->use_update_info);
@@ -5064,6 +5208,7 @@ test_size(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
          if (fail(pm))
             return 0;
 
+#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
          standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
             PNG_INTERLACE_ADAM7, w, h, 0), 0/*do_interlace*/,
             pm->use_update_info);
@@ -5077,6 +5222,7 @@ test_size(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
 
          if (fail(pm))
             return 0;
+#     endif
 
          /* Now validate the interlaced read side - do_interlace true,
           * in the progressive case this does actually make a difference
@@ -5089,12 +5235,14 @@ test_size(png_modifier* PNG_CONST pm, png_byte PNG_CONST colour_type,
          if (fail(pm))
             return 0;
 
+#     ifdef PNG_WRITE_INTERLACING_SUPPORTED
          standard_test(&pm->this, FILEID(colour_type, DEPTH(bdlo), 0/*palette*/,
             PNG_INTERLACE_ADAM7, w, h, 0), 1/*do_interlace*/,
             pm->use_update_info);
 
          if (fail(pm))
             return 0;
+#     endif
       }
    }
 
@@ -5705,7 +5853,7 @@ transform_info_imp(transform_display *dp, png_structp pp, png_infop pi)
    }
 }
 
-static void
+static void PNGCBAPI
 transform_info(png_structp pp, png_infop pi)
 {
    transform_info_imp(voidcast(transform_display*, png_get_progressive_ptr(pp)),
@@ -5912,7 +6060,7 @@ transform_image_validate(transform_display *dp, png_const_structp pp,
    dp->this.ps->validated = 1;
 }
 
-static void
+static void PNGCBAPI
 transform_end(png_structp ppIn, png_infop pi)
 {
    png_const_structp pp = ppIn;
@@ -6004,7 +6152,7 @@ transform_test(png_modifier *pmIn, PNG_CONST png_uint_32 idIn,
 
    Catch(fault)
    {
-      modifier_reset((png_modifier*)fault);
+      modifier_reset(voidcast(png_modifier*,(void*)fault));
    }
 }
 
@@ -6645,6 +6793,14 @@ image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this,
           *  conversion adds another +/-2 in the 16-bit case and
           *  +/-(1<<(15-PNG_MAX_GAMMA_8)) in the 8-bit case.
           */
+         that->pm->limit +=
+#        if PNG_MAX_GAMMA_8 < 14
+               pow((that->this.bit_depth == 16 ?
+                  8. : 6. + (1<<(15-PNG_MAX_GAMMA_8)))/65535, data.gamma);
+#        else
+               pow((that->this.bit_depth == 16 ?
+                  8. : 8. + (1<<(15-PNG_MAX_GAMMA_8)))/65535, data.gamma);
+#        endif
          that->pm->limit += pow(
 #           if PNG_MAX_GAMMA_8 < 14
                (that->this.bit_depth == 16 ? 8. :
@@ -6660,8 +6816,22 @@ image_transform_png_set_rgb_to_gray_ini(PNG_CONST image_transform *this,
          /* Rounding to 8 bits in the linear space causes massive errors which
           * will trigger the error check in transform_range_check.  Fix that
           * here by taking the gamma encoding into account.
+          *
+          * When DIGITIZE is set because a pre-1.7 version of libpng is being
+          * tested allow a bigger slack.
+          *
+          * NOTE: this magic number was determined by experiment to be 1.1 (when
+          * using fixed point arithmetic).  There's no great merit to the value
+          * below, however it only affects the limit used for checking for
+          * internal calculation errors, not the actual limit imposed by
+          * pngvalid on the output errors.
           */
-         that->pm->limit += pow(1./255, data.gamma);
+         that->pm->limit +=
+#        if DIGITIZE
+             pow(1.1 /255, data.gamma);
+#        else
+             pow(1.0 /255, data.gamma);
+#        endif
       }
    }
 
@@ -7267,7 +7437,7 @@ transform_enable(PNG_CONST char *name)
    {
       fprintf(stderr, "pngvalid: --transform-enable=%s: unknown transform\n",
          name);
-      exit(1);
+      exit(99);
    }
 }
 
@@ -7289,7 +7459,7 @@ transform_disable(PNG_CONST char *name)
 
    fprintf(stderr, "pngvalid: --transform-disable=%s: unknown transform\n",
       name);
-   exit(1);
+   exit(99);
 }
 
 static void
@@ -7714,7 +7884,7 @@ gamma_info_imp(gamma_display *dp, png_structp pp, png_infop pi)
    standard_info_part2(&dp->this, pp, pi, 1 /*images*/);
 }
 
-static void
+static void PNGCBAPI
 gamma_info(png_structp pp, png_infop pi)
 {
    gamma_info_imp(voidcast(gamma_display*, png_get_progressive_ptr(pp)), pp,
@@ -8678,7 +8848,7 @@ gamma_image_validate(gamma_display *dp, png_const_structp pp,
    dp->this.ps->validated = 1;
 }
 
-static void
+static void PNGCBAPI
 gamma_end(png_structp ppIn, png_infop pi)
 {
    png_const_structp pp = ppIn;
@@ -8848,7 +9018,7 @@ gamma_test(png_modifier *pmIn, PNG_CONST png_byte colour_typeIn,
    }
 
    Catch(fault)
-      modifier_reset((png_modifier*)fault);
+      modifier_reset(voidcast(png_modifier*,(void*)fault));
 }
 
 static void gamma_threshold_test(png_modifier *pm, png_byte colour_type,
@@ -9640,7 +9810,7 @@ perform_interlace_macro_validation(void)
       if (m != f)
       {
          fprintf(stderr, "PNG_PASS_START_ROW(%d) = %u != %x\n", pass, m, f);
-         exit(1);
+         exit(99);
       }
 
       m = PNG_PASS_START_COL(pass);
@@ -9648,7 +9818,7 @@ perform_interlace_macro_validation(void)
       if (m != f)
       {
          fprintf(stderr, "PNG_PASS_START_COL(%d) = %u != %x\n", pass, m, f);
-         exit(1);
+         exit(99);
       }
 
       m = PNG_PASS_ROW_SHIFT(pass);
@@ -9656,7 +9826,7 @@ perform_interlace_macro_validation(void)
       if (m != f)
       {
          fprintf(stderr, "PNG_PASS_ROW_SHIFT(%d) = %u != %x\n", pass, m, f);
-         exit(1);
+         exit(99);
       }
 
       m = PNG_PASS_COL_SHIFT(pass);
@@ -9664,7 +9834,7 @@ perform_interlace_macro_validation(void)
       if (m != f)
       {
          fprintf(stderr, "PNG_PASS_COL_SHIFT(%d) = %u != %x\n", pass, m, f);
-         exit(1);
+         exit(99);
       }
 
       /* Macros that depend on the image or sub-image height too:
@@ -9685,7 +9855,7 @@ perform_interlace_macro_validation(void)
          {
             fprintf(stderr, "PNG_ROW_FROM_PASS_ROW(%u, %d) = %u != %x\n",
                v, pass, m, f);
-            exit(1);
+            exit(99);
          }
 
          m = PNG_COL_FROM_PASS_COL(v, pass);
@@ -9694,7 +9864,7 @@ perform_interlace_macro_validation(void)
          {
             fprintf(stderr, "PNG_COL_FROM_PASS_COL(%u, %d) = %u != %x\n",
                v, pass, m, f);
-            exit(1);
+            exit(99);
          }
 
          m = PNG_ROW_IN_INTERLACE_PASS(v, pass);
@@ -9703,7 +9873,7 @@ perform_interlace_macro_validation(void)
          {
             fprintf(stderr, "PNG_ROW_IN_INTERLACE_PASS(%u, %d) = %u != %x\n",
                v, pass, m, f);
-            exit(1);
+            exit(99);
          }
 
          m = PNG_COL_IN_INTERLACE_PASS(v, pass);
@@ -9712,7 +9882,7 @@ perform_interlace_macro_validation(void)
          {
             fprintf(stderr, "PNG_COL_IN_INTERLACE_PASS(%u, %d) = %u != %x\n",
                v, pass, m, f);
-            exit(1);
+            exit(99);
          }
 
          /* Then the base 1 stuff: */
@@ -9723,7 +9893,7 @@ perform_interlace_macro_validation(void)
          {
             fprintf(stderr, "PNG_PASS_ROWS(%u, %d) = %u != %x\n",
                v, pass, m, f);
-            exit(1);
+            exit(99);
          }
 
          m = PNG_PASS_COLS(v, pass);
@@ -9732,7 +9902,7 @@ perform_interlace_macro_validation(void)
          {
             fprintf(stderr, "PNG_PASS_COLS(%u, %d) = %u != %x\n",
                v, pass, m, f);
-            exit(1);
+            exit(99);
          }
 
          /* Move to the next v - the stepping algorithm starts skipping
@@ -9921,12 +10091,12 @@ int main(int argc, char **argv)
 
    /* Store the test gammas */
    pm.gammas = gammas;
-   pm.ngammas = (sizeof gammas) / (sizeof gammas[0]);
+   pm.ngammas = ARRAY_SIZE(gammas);
    pm.ngamma_tests = 0; /* default to off */
 
    /* And the test encodings */
    pm.encodings = test_encodings;
-   pm.nencodings = (sizeof test_encodings) / (sizeof test_encodings[0]);
+   pm.nencodings = ARRAY_SIZE(test_encodings);
 
    pm.sbitlow = 8U; /* because libpng doesn't do sBIT below 8! */
 
@@ -10098,7 +10268,14 @@ int main(int argc, char **argv)
          ++pm.use_update_info; /* Can call multiple times */
 
       else if (strcmp(*argv, "--interlace") == 0)
-         pm.interlace_type = PNG_INTERLACE_ADAM7;
+      {
+#        ifdef PNG_WRITE_INTERLACING_SUPPORTED
+            pm.interlace_type = PNG_INTERLACE_ADAM7;
+#        else
+            fprintf(stderr, "pngvalid: no write interlace support\n");
+            return SKIP;
+#        endif
+      }
 
       else if (strcmp(*argv, "--use-input-precision") == 0)
          pm.use_input_precision = 1U;
@@ -10156,7 +10333,7 @@ int main(int argc, char **argv)
          else
          {
             fprintf(stderr, "pngvalid: %s: unknown 'max' option\n", *argv);
-            exit(1);
+            exit(99);
          }
 
          catmore = 1;
@@ -10168,10 +10345,53 @@ int main(int argc, char **argv)
       else if (strcmp(*argv, "--log16") == 0)
          --argc, pm.log16 = atof(*++argv), catmore = 1;
 
+#ifdef PNG_SET_OPTION_SUPPORTED
+      else if (strncmp(*argv, "--option=", 9) == 0)
+      {
+         /* Syntax of the argument is <option>:{on|off} */
+         const char *arg = 9+*argv;
+         unsigned char option=0, setting=0;
+
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+         if (strncmp(arg, "arm-neon:", 9) == 0)
+            option = PNG_ARM_NEON, arg += 9;
+
+         else
+#endif
+#ifdef PNG_MAXIMUM_INFLATE_WINDOW
+         if (strncmp(arg, "max-inflate-window:", 19) == 0)
+            option = PNG_MAXIMUM_INFLATE_WINDOW, arg += 19;
+
+         else
+#endif
+         {
+            fprintf(stderr, "pngvalid: %s: %s: unknown option\n", *argv, arg);
+            exit(99);
+         }
+
+         if (strcmp(arg, "off") == 0)
+            setting = PNG_OPTION_OFF;
+
+         else if (strcmp(arg, "on") == 0)
+            setting = PNG_OPTION_ON;
+
+         else
+         {
+            fprintf(stderr,
+               "pngvalid: %s: %s: unknown setting (use 'on' or 'off')\n",
+               *argv, arg);
+            exit(99);
+         }
+
+         pm.this.options[pm.this.noptions].option = option;
+         pm.this.options[pm.this.noptions++].setting = setting;
+      }
+#endif /* PNG_SET_OPTION_SUPPORTED */
+
       else
       {
          fprintf(stderr, "pngvalid: %s: unknown argument\n", *argv);
-         exit(1);
+         exit(99);
       }
 
       if (catmore) /* consumed an extra *argv */
@@ -10345,12 +10565,17 @@ int main(int argc, char **argv)
       }
    }
 
+   /* This is required because some very minimal configurations do not use it:
+    */
+   UNUSED(fail)
    return 0;
 }
-#else /* write not supported */
+#else /* write or low level APIs not supported */
 int main(void)
 {
-   fprintf(stderr, "pngvalid: no write support in libpng, all tests skipped\n");
-   return 0;
+   fprintf(stderr,
+      "pngvalid: no low level write support in libpng, all tests skipped\n");
+   /* So the test is skipped: */
+   return SKIP;
 }
 #endif

contrib/libtests/readpng.c

@@ -2,7 +2,7 @@
  *
  * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/libtests/tarith.c

@@ -1,9 +1,9 @@
 
 /* tarith.c
  *
- * Copyright (c) 2011,2012 John Cunningham Bowler
+ * Copyright (c) 2011-2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/libtests/timepng.c

@@ -1,8 +1,8 @@
 /* timepng.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/pngminim/decoder/makefile

@@ -14,7 +14,8 @@ LD=$(CC)
 RM=rm -f
 COPY=cp
 
-CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP -I. -O1
+CPPFLAGS=-I. -DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP
+CFLAGS=-O1 -Wall
 
 C=.c
 O=.o
@@ -81,7 +82,7 @@ OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
 
 # note: dependencies do not work on implicit rule lines
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) $(CPPFLAGS) -c $(CFLAGS) $<
 
 # dependencies
 
@@ -95,16 +96,16 @@ pngm2pnm$(E): $(OBJS)
 # The CPP_FLAGS setting causes pngusr.h to be included in
 # both the build of pnglibconf.h and, subsequently, when
 # building libpng itself.
-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak $(ZH)\
 	$(PNGSRC)/scripts/pnglibconf.dfa \
 	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
 	$(RM) pnglibconf.h pnglibconf.dfn
-	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
-	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	$(MAKE) -f $(PNGSRC)/scripts/pnglibconf.mak $(MAKEFLAGS)\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG -I."\
 	    DFA_XTRA="pngusr.dfa" $@
 
 clean:
-	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	$(MAKE) -f $(PNGSRC)/scripts/pnglibconf.mak $(MAKEFLAGS)\
 	    srcdir=$(PNGSRC) clean
 	$(RM) pngm2pnm$(O)
 	$(RM) pngm2pnm$(E)

contrib/pngminim/decoder/pngusr.dfa

@@ -1,6 +1,6 @@
 # pngminim/decoder/pngusr.dfa
 #
-# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+# Copyright (c) 2010-2013 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer

contrib/pngminim/decoder/pngusr.h

@@ -1,6 +1,6 @@
 /* minrdpngconf.h: headers to make a minimal png-read-only library
  *
- * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ * Copyright (c) 2007, 2010-2013 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -18,7 +18,6 @@
  * affect the API (so are not recorded in pnglibconf.h)
  */
 
-#define PNG_NO_WARNINGS
 #define PNG_ALIGN_TYPE PNG_ALIGN_NONE
 
 #endif /* MINRDPNGCONF_H */

contrib/pngminim/encoder/makefile

@@ -14,7 +14,8 @@ LD=$(CC)
 RM=rm -f
 COPY=cp
 
-CFLAGS=-DPNG_USER_CONFIG -DZ_SOLO -DNO_GZIP -I. -O1
+CPPFLAGS=-I. -DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP
+CFLAGS=-O1 -Wall
 
 C=.c
 O=.o
@@ -80,7 +81,7 @@ OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) $(CPPFLAGS) -c $(CFLAGS) $<
 
 # dependencies
 
@@ -94,16 +95,16 @@ pnm2pngm$(E): $(OBJS)
 # The CPP_FLAGS setting causes pngusr.h to be included in
 # both the build of pnglibconf.h and, subsequently, when
 # building libpng itself.
-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak $(ZH)\
 	$(PNGSRC)/scripts/pnglibconf.dfa \
 	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
 	$(RM) pnglibconf.h pnglibconf.dfn
-	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
-	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	$(MAKE) -f $(PNGSRC)/scripts/pnglibconf.mak $(MAKEFLAGS)\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG -I."\
 	    DFA_XTRA="pngusr.dfa" $@
 
 clean:
-	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	$(MAKE) -f $(PNGSRC)/scripts/pnglibconf.mak $(MAKEFLAGS)\
 	    srcdir=$(PNGSRC) clean
 	$(RM) pnm2pngm$(O)
 	$(RM) pnm2pngm$(E)

contrib/pngminim/encoder/pngusr.dfa

@@ -1,6 +1,6 @@
 # pngminim/encoder/pngusr.dfa
 #
-# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+# Copyright (c) 2010-2013 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -14,6 +14,10 @@ everything = off
 
 option WRITE on
 
+# These 2 options are required if you need to read PBM (P1 or P4) files.
+option WRITE_INVERT on
+option WRITE_PACK on
+
 # You must choose fixed or floating point arithmetic:
 # option FLOATING_POINT on
 

contrib/pngminim/encoder/pngusr.h

@@ -1,6 +1,6 @@
 /* minwrpngconf.h: headers to make a minimal png-write-only library
  *
- * Copyright (c) 2007, 2010-2011 Glenn Randers-Pehrson
+ * Copyright (c) 2007, 2010-2013 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -18,7 +18,6 @@
  * affect the API (so are not recorded in pnglibconf.h)
  */
 
-#define PNG_NO_WARNINGS
 #define PNG_ALIGN_TYPE PNG_ALIGN_NONE
 
 #endif /* MINWRPNGCONF_H */

contrib/pngminim/preader/makefile

@@ -30,7 +30,8 @@ XLIB = -L/usr/X11R6/lib -lX11
 #LIBS = $(XLIB)
 LIBS = $(XLIB) -lm                      #platforms that need libm
 
-CFLAGS=-DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP -I. $(XINC) -O1
+CPPFLAGS=-I. $(XINC) -DPNG_USER_CONFIG -DNO_GZCOMPRESS -DZ_SOLO -DNO_GZIP
+CFLAGS=-O1 -Wall
 
 C=.c
 O=.o
@@ -96,7 +97,7 @@ OBJS    = $(PROGOBJS) $(PNGOBJS) $(ZOBJS)
 # implicit make rules -------------------------------------------------------
 
 .c$(O):
-	$(CC) -c $(CFLAGS) $<
+	$(CC) $(CPPFLAGS) -c $(CFLAGS) $<
 
 # dependencies
 
@@ -110,16 +111,16 @@ rpng2-x$(E): $(OBJS)
 # The CPP_FLAGS setting causes pngusr.h to be included in
 # both the build of pnglibconf.h and, subsequently, when
 # building libpng itself.
-$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak\
+$(PNGCONF): $(PNGSRC)/scripts/pnglibconf.mak $(ZH)\
 	$(PNGSRC)/scripts/pnglibconf.dfa \
 	$(PNGSRC)/scripts/options.awk pngusr.h pngusr.dfa
 	$(RM) pnglibconf.h pnglibconf.dfn
-	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
-	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG"\
+	$(MAKE) -f $(PNGSRC)/scripts/pnglibconf.mak $(MAKEFLAGS)\
+	    srcdir=$(PNGSRC) CPPFLAGS="-DPNG_USER_CONFIG -I."\
 	    DFA_XTRA="pngusr.dfa" $@
 
 clean:
-	$(MAKE) $(MAKEFLAGS) -f $(PNGSRC)/scripts/pnglibconf.mak\
+	$(MAKE) -f $(PNGSRC)/scripts/pnglibconf.mak $(MAKEFLAGS)\
 	    srcdir=$(PNGSRC) clean
 	$(RM) rpng2-x$(O)
 	$(RM) rpng2-x$(E)

contrib/pngminim/preader/pngusr.dfa

@@ -1,6 +1,6 @@
 # pngminim/preader/pngusr.dfa
 #
-# Copyright (c) 2010-2011 Glenn Randers-Pehrson
+# Copyright (c) 2010-2013 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer

contrib/pngminim/preader/pngusr.h

@@ -1,6 +1,6 @@
 /* minrdpngconf.h: headers to make a minimal png-read-only library
  *
- * Copyright (c) 2009, 2010-2011 Glenn Randers-Pehrson
+ * Copyright (c) 2009, 2010-2013 Glenn Randers-Pehrson
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -18,7 +18,6 @@
  * affect the API (so are not recorded in pnglibconf.h)
  */
 
-#define PNG_NO_WARNINGS
 #define PNG_ALIGN_TYPE PNG_ALIGN_NONE
 
 #endif /* MINPRDPNGCONF_H */

contrib/pngminus/pnm2png.c

@@ -198,9 +198,9 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   char          height_token[16];
   char          maxval_token[16];
   int           color_type;
-  unsigned long   ul_width, ul_alpha_width;
-  unsigned long   ul_height, ul_alpha_height;
-  unsigned long   ul_maxval;
+  unsigned long   ul_width=0, ul_alpha_width=0;
+  unsigned long   ul_height=0, ul_alpha_height=0;
+  unsigned long   ul_maxval=0;
   png_uint_32   width, alpha_width;
   png_uint_32   height, alpha_height;
   png_uint_32   maxval;
@@ -210,6 +210,9 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   int           alpha_present;
   int           row, col;
   BOOL          raw, alpha_raw = FALSE;
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  BOOL          packed_bitmap = FALSE;
+#endif
   png_uint_32   tmp16;
   int           i;
 
@@ -222,9 +225,21 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
   }
   else if ((type_token[1] == '1') || (type_token[1] == '4'))
   {
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
     raw = (type_token[1] == '4');
     color_type = PNG_COLOR_TYPE_GRAY;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &ul_width);
+    width = (png_uint_32) ul_width;
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &ul_height);
+    height = (png_uint_32) ul_height;
     bit_depth = 1;
+    packed_bitmap = TRUE;
+#else
+    fprintf (stderr, "PNM2PNG built without PNG_WRITE_INVERT_SUPPORTED and \n");
+    fprintf (stderr, "PNG_WRITE_PACK_SUPPORTED can't read PBM (P1,P4) files\n");
+#endif
   }
   else if ((type_token[1] == '2') || (type_token[1] == '5'))
   {
@@ -343,8 +358,14 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
 
   alpha_present = (channels - 1) % 2;
 
-  /* row_bytes is the width x number of channels x (bit-depth / 8) */
-  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  if (packed_bitmap)
+    /* row data is as many bytes as can fit width x channels x bit_depth */
+    row_bytes = (width * channels * bit_depth + 7) / 8;
+  else
+#endif
+    /* row_bytes is the width x number of channels x (bit-depth / 8) */
+    row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
 
   if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
     return FALSE;
@@ -354,40 +375,48 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
 
   for (row = 0; row < height; row++)
   {
-    for (col = 0; col < width; col++)
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+    if (packed_bitmap) {
+      for (i = 0; i < row_bytes; i++)
+        /* png supports this format natively so no conversion is needed */
+        *pix_ptr++ = get_data (pnm_file, 8);
+    } else
+#endif
     {
-      for (i = 0; i < (channels - alpha_present); i++)
+      for (col = 0; col < width; col++)
       {
-        if (raw)
-          *pix_ptr++ = get_data (pnm_file, bit_depth);
-        else
-          if (bit_depth <= 8)
-            *pix_ptr++ = get_value (pnm_file, bit_depth);
+        for (i = 0; i < (channels - alpha_present); i++)
+        {
+          if (raw)
+            *pix_ptr++ = get_data (pnm_file, bit_depth);
           else
-          {
-            tmp16 = get_value (pnm_file, bit_depth);
-            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
-            pix_ptr++;
-            *pix_ptr = (png_byte) (tmp16 & 0xFF);
-            pix_ptr++;
-          }
-      }
+            if (bit_depth <= 8)
+              *pix_ptr++ = get_value (pnm_file, bit_depth);
+            else
+            {
+              tmp16 = get_value (pnm_file, bit_depth);
+              *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
+              pix_ptr++;
+              *pix_ptr = (png_byte) (tmp16 & 0xFF);
+              pix_ptr++;
+            }
+        }
 
-      if (alpha) /* read alpha-channel from pgm file */
-      {
-        if (alpha_raw)
-          *pix_ptr++ = get_data (alpha_file, alpha_depth);
-        else
-          if (alpha_depth <= 8)
-            *pix_ptr++ = get_value (alpha_file, bit_depth);
+        if (alpha) /* read alpha-channel from pgm file */
+        {
+          if (alpha_raw)
+            *pix_ptr++ = get_data (alpha_file, alpha_depth);
           else
-          {
-            tmp16 = get_value (alpha_file, bit_depth);
-            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
-            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
-          }
-      } /* if alpha */
-
+            if (alpha_depth <= 8)
+              *pix_ptr++ = get_value (alpha_file, bit_depth);
+            else
+            {
+              tmp16 = get_value (alpha_file, bit_depth);
+              *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
+              *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
+            }
+        } /* if alpha */
+      } /* if packed_bitmap */
     } /* end for col */
   } /* end for row */
 
@@ -404,6 +433,14 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
     return FALSE;
   }
 
+#if defined(PNG_WRITE_INVERT_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
+  if (packed_bitmap == TRUE)
+  {
+    png_set_packing (png_ptr);
+    png_set_invert_mono (png_ptr);
+  }
+#endif
+
   /* setjmp() must be called in every function that calls a PNG-reading libpng function */
   if (setjmp (png_jmpbuf(png_ptr)))
   {
@@ -460,19 +497,32 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
 void get_token(FILE *pnm_file, char *token)
 {
   int i = 0;
+  int ret;
 
-  /* remove white-space */
+  /* remove white-space and comment lines */
   do
   {
-    token[i] = (unsigned char) fgetc (pnm_file);
+    ret = fgetc(pnm_file);
+    if (ret == '#') {
+      /* the rest of this line is a comment */
+      do
+      {
+        ret = fgetc(pnm_file);
+      }
+      while ((ret != '\n') && (ret != '\r') && (ret != EOF));
+    }
+    if (ret == EOF) break;
+    token[i] = (unsigned char) ret;
   }
   while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
 
   /* read string */
   do
   {
+    ret = fgetc(pnm_file);
+    if (ret == EOF) break;
     i++;
-    token[i] = (unsigned char) fgetc (pnm_file);
+    token[i] = (unsigned char) ret;
   }
   while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
 

contrib/tools/checksum-icc.c

@@ -1,8 +1,8 @@
 /* checksum-icc.c
  *
- * Copyright (c) 2012 John Cunningham Bowler
+ * Copyright (c) 2013 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/tools/chunkhash.c

@@ -0,0 +1,437 @@
+/* chunkhash.c -- build a perfect hash code for the chunk names on stdin.
+ *
+ * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ *
+ * COPYRIGHT: Written by John Cunningham Bowler, 2014.
+ * To the extent possible under law, the author has waived all copyright and
+ * related or neighboring rights to this work.  This work is published from:
+ * United States.
+ *
+ * Feed this program all the known chunks that libpng must recognize.  It will
+ * generate an appropriate hash key for the macro in pngpriv.h  To generate the
+ * list of chunks currently defined in png.h do this:
+ *
+ *    sed -n -e 's/^#define png_\(....\) PNG_U32.*$/\1/p' png.h
+ *
+ * An alternative to using this program is to pipe the output of the above
+ * through gperf, however the code generated by perf is somewhat more verbose
+ * and it doesn't generate as good a result (however it's a heck of a lot faster
+ * than this program!)
+ */
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <png.h> /* for the libpng types for this platform */
+
+/* The machine generated file is checked in, so this works and it obtains the
+ * definition of the PNG_CHUNK_HASH macro.  To change this definition only ever
+ * alter the strings below!
+ */
+#include "chunkhash.h"
+
+/* The best_ variables are local variables defined in the functions below.  When
+ * used in libpng code, however, they are just constants.
+ */
+#define PNG_CHUNK_HASH_MASK best_mask
+#define PNG_CHUNK_HASH_C0 best_c[0]
+#define PNG_CHUNK_HASH_C1 best_c[1]
+#define PNG_CHUNK_HASH_C2 best_c[2]
+#define PNG_CHUNK_HASH_C3 best_c[3]
+
+/* These strings contain the C text to copy into the new version of
+ * contrib/tools/chunkhash.c
+ */
+static const char *strings[] = {
+"/* chunkhash.h -- a perfect hash code for the chunk names in png.h",
+" *",
+" * Last changed in libpng 1.7.0 [(PENDING RELEASE)]",
+" *",
+" * THIS IS A MACHINE GENERATED FILE.  See contrib/tools/chunkhash.c for",
+" * copyright and other information.",
+" *",
+" * USAGE:  To include the PNG_CHUNK_HASH macro and associated definitions:",
+" *",
+" * #define PNG_CHUNKHASH_DEFS",
+" * #include \"contrib/tools/chunkhash.h\"",
+" *",
+" * To define the png_chunk_hash array used by the macro:",
+" *",
+" * #define PNG_CHUNKHASH_CODE",
+" * #include \"contrib/tools/chunkhash.h\"",
+" *",
+" * One or both of the defines must be given except when building chunkhash",
+" * itself.",
+" */",
+"#ifdef PNG_CHUNKHASH_DEFS",
+"#ifndef PNG_CHUNKHASH_H",
+"#define PNG_CHUNKHASH_H",
+"/* A perfect hash code - returns a value 0..(PNG_KNOWN_CHUNK_COUNT-1) and is",
+" * generated by the ridiculously simple program in contrib/tools/chunkhash.c",
+" *",
+" * The hash code used here multiplies each byte by a different constant to",
+" * return a single number:",
+" *",
+" *    b0 * c[0] + b1 * [c1] + b2 * c[2] + b3 * c[3]",
+" *",
+" * The values of the constants are found by search using the a table of",
+" * primes, including 0, and may be (in fact are at present) 0 for some of the",
+" * bytes, the compiler is expected to optimize multiply by zero, or one!",
+" *",
+" * The lookup table reduces the sparse result of the hash calculation to the",
+" * correct index values.  The chunks are indexed in the string order of the",
+" * png_uint_32 chunk names.",
+" */",
+0, /* HEADER definitions go here */
+"",
+"extern const png_byte png_chunk_hash[PNG_CHUNK_HASH_MASK+1];",
+"#endif /* !PNG_CHUNKHASH_H */",
+"#endif /* PNG_CHUNKHASH_DEFS */",
+"",
+"#ifndef PNG_CHUNK_HASH",
+"#define PNG_CHUNK_HASH(chunk) (png_chunk_hash[PNG_CHUNK_HASH_MASK & (\\",
+"      ((chunk) >> 24) * PNG_CHUNK_HASH_C0 +\\",
+"      ((chunk) >> 16) * PNG_CHUNK_HASH_C1 +\\",
+"      ((chunk) >>  8) * PNG_CHUNK_HASH_C2 +\\",
+"      ((chunk)      ) * PNG_CHUNK_HASH_C3)])",
+"#endif",
+"",
+"#ifdef PNG_CHUNKHASH_CODE",
+"#ifndef PNG_CHUNKHASH_C",
+"#define PNG_CHUNKHASH_C",
+"const png_byte png_chunk_hash[PNG_CHUNK_HASH_MASK+1] = {",
+0, /* png.c definitions go here */
+"};",
+"#endif /* !PNG_CHUNKHASH_C */",
+"#endif /* PNG_CHUNKHASH_CODE */",
+0 /* end of file */
+};
+
+#define CHUNK_COUNT_MAX 32
+   /* If necessary this is easy to increase; just don't use a png_uint_32
+    * bitmask below, however it doesn't seem likely that the limit will be hit
+    * any time soon.
+    */
+
+static const png_byte
+chunk_hash[256] =
+{
+   0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21,
+   22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+   41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,
+   60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,
+   79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97,
+   98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113,
+   114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128,
+   129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143,
+   144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158,
+   159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 170, 171, 172, 173,
+   174, 175, 176, 177, 178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188,
+   189, 190, 191, 192, 193, 194, 195, 196, 197, 198, 199, 200, 201, 202, 203,
+   204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218,
+   219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232, 233,
+   234, 235, 236, 237, 238, 239, 240, 241, 242, 243, 244, 245, 246, 247, 248,
+   249, 250, 251, 252, 253, 254, 255
+};
+
+static void
+error(const char *string)
+{
+   fprintf(stderr, "chunkhash: %s\n", string);
+   exit(1);
+}
+
+/* Return a hash code for the given chunk; this is the same as the pngpriv.h
+ * macro, but parameterized.  The names of the parameters have to be chosen to
+ * match the above #defines.
+ */
+static png_uint_32
+test_hash(png_uint_32 chunk, const unsigned int *best_c, png_uint_32 best_mask)
+{
+#  define png_chunk_hash chunk_hash /* prevents lookup */
+      return PNG_CHUNK_HASH(chunk);
+#  undef png_chunk_hash
+}
+
+static void
+print_chunks(const png_uint_32 *chunks, unsigned int nchunks, png_uint_32 first,
+   png_uint_32 last, const unsigned int *best_c, png_uint_32 best_mask,
+   const png_byte *lut)
+{
+   /* 'last' is the last code to print plus 1, this is used to detect duplicates
+    * (which should not happen - if there are any it's an internal error!)
+    */
+   if (nchunks > 0)
+   {
+      /* Recursive algorithm; find the hash code of the next chunk, then print
+       * all remaining chunks with codes in the range first..code (including
+       * duplicates) and after print all remaining chunks with codes in the
+       * range (code+1)..last
+       */
+      const png_uint_32 chunk = *chunks++;
+#     define png_chunk_hash lut
+         const png_uint_32 code = PNG_CHUNK_HASH(chunk);
+#     undef png_chunk_hash
+
+      --nchunks;
+
+      /* The code might be out of the print range */
+      if (code >= first && code <= last)
+      {
+         if (code >= first) /* not time yet */
+            print_chunks(chunks, nchunks, first, code, best_c, best_mask, lut);
+
+         printf("#define PNG_CHUNK_%c%c%c%c_TAG %lu%s\n", (char)(chunk>>24),
+            (char)(chunk>>16), (char)(chunk>>8), (char)chunk,
+            (unsigned long)code, code == last ? " /* DUPLICATE */" : "");
+
+         if (code < last) /* still some to go */
+            print_chunks(chunks, nchunks, code+1, last, best_c, best_mask, lut);
+      }
+
+      else
+         print_chunks(chunks, nchunks, first, last, best_c, best_mask, lut);
+   }
+}
+
+static unsigned int primes[] =
+{
+   0, 1, 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67,
+   71, 73, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149,
+   151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199, 211, 223, 227, 229,
+   233, 239, 241, 251
+};
+
+#define NPRIMES ((sizeof primes)/(sizeof primes[0]))
+
+int
+main(void)
+{
+   /* Stdin should just contain chunk names, one per line */
+   png_uint_32 best_mask;
+   unsigned int best_c[4];
+   png_uint_32 chunks[CHUNK_COUNT_MAX];
+   png_byte known_chunk_count;
+
+   /* Not required; stop GCC whining: */
+   memset(best_c, 0xab, sizeof best_c);
+   best_mask = 0x12345678;
+
+   {
+      png_uint_32 this_chunk = 0;
+      png_byte n_chunks = 0;
+
+      for (;;)
+      {
+         int ch = getchar();
+
+         if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z'))
+         {
+            if (this_chunk > 0xffffffU)
+               error("chunk name too long");
+
+            this_chunk = (this_chunk << 8) + (unsigned)ch;
+         }
+
+         else
+         {
+            if (this_chunk > 0)
+            {
+               if (this_chunk <= 0xffffffU)
+                  error("chunk name too short");
+
+               if (n_chunks >= CHUNK_COUNT_MAX)
+                  error("too many chunks (check CHUNK_COUNT_MAX)");
+
+               chunks[n_chunks++] = this_chunk;
+               this_chunk = 0;
+            }
+         }
+
+         if (ch < 0)
+            break;
+      }
+
+      /* 22 is the number of chunks currently defined (excluding fRAc), at any
+       * time it should also be in PNG_KNOWN_CHUNK_COUNT, but this run of
+       * chunkhash may be trying to add a chunk so allow bigger numbers.
+       */
+#     ifdef PNG_KNOWN_CHUNK_COUNT
+#        define CHUNK_COUNT_MIN PNG_KNOWN_CHUNK_COUNT
+#     else
+#        define CHUNK_COUNT_MIN 26
+#     endif
+      if (n_chunks < CHUNK_COUNT_MIN)
+         error("too few chunks (expecting at least 26)");
+
+      known_chunk_count = n_chunks;
+   }
+
+   /* Exhaustive search of the hash parameters - in fact this isn't very slow at
+    * all.
+    */
+   {
+      unsigned int i1, c_zero = 0, c_one = 0;
+
+      for (i1=0; i1<NPRIMES; ++i1)
+      {
+         unsigned int i2;
+         unsigned int c[4];
+
+         fprintf(stderr, "TEST: %u\n", primes[i1]);
+         c[0] = primes[i1];
+
+         for (i2=0; i2<NPRIMES; ++i2)
+         {
+            unsigned int i3;
+
+            c[1] = primes[i2];
+
+            for (i3=0; i3<NPRIMES; ++i3)
+            {
+               unsigned int i4;
+
+               c[2] = primes[i3];
+
+               for (i4=0; i4<NPRIMES; ++i4)
+               {
+                  unsigned int i;
+                  png_uint_32 hash_mask = 0xffU;
+                  png_uint_32 hashes[CHUNK_COUNT_MAX];
+
+                  c[3] = primes[i4];
+
+                  while (hash_mask > 0xfU)
+                  {
+                     for (i=0; i<known_chunk_count; ++i)
+                     {
+                        unsigned int j;
+                        png_uint_32 hash = test_hash(chunks[i], c, hash_mask);
+
+                        for (j=0; j<i; ++j) if (hashes[j] == hash) goto next_i4;
+
+                        hashes[i] = hash;
+                     }
+
+                     hash_mask >>= 1;
+                  }
+
+               next_i4:
+                  if (hash_mask < 0xffU)
+                  {
+                     /* This worked */
+                     unsigned int best, c0 = 0, c1 = 0;
+
+                     hash_mask <<= 1;
+                     hash_mask += 1;
+
+                     for (i=0; i<4; ++i)
+                     {
+                        if (c[i] == 0)
+                           ++c0;
+
+                        else if (c[i] == 1)
+                           ++c1;
+                     }
+
+                     if (hash_mask == best_mask)
+                        best = (c0 > c_zero) || (c0 == c_zero && c1 > c_one);
+
+                     else
+                        best = (hash_mask < best_mask);
+
+                     if (best)
+                     {
+                        fprintf(stderr, "{%u,%u,%u,%u} & 0x%lx\n",
+                           c[0], c[1], c[2], c[3],
+                           (unsigned long)hash_mask);
+
+                        c_zero = c0;
+                        c_one = c1;
+                        best_mask = hash_mask;
+                        memcpy(best_c, c, sizeof best_c);
+                     }
+                  }
+               } /* i4 */
+            } /* i3 */
+         } /* i2 */
+      } /* i1 */
+   }
+
+   /* Calculate the LUT (png_chunk_hash) */
+   {
+      png_byte b;
+      png_byte lut[256];
+
+      /* A failure returns PNG_KNOWN_CHUNK_COUNT: */
+      memset(lut, known_chunk_count, sizeof lut);
+
+      for (b=0; b<known_chunk_count; ++b)
+         lut[test_hash(chunks[b], best_c, best_mask)] = b;
+
+      /* Validate the pngpriv.h hash function. */
+#     define png_chunk_hash lut
+         {
+            unsigned int i;
+
+            for (i=0; i<known_chunk_count; ++i)
+            {
+               png_uint_32 chunk = chunks[i];
+
+               if (PNG_CHUNK_HASH(chunk) != i)
+                  error("internal error: hash didn't work!");
+            }
+         }
+#     undef lut
+
+      /* Print all the results, first the stuff for pngpriv.h */
+      {
+         unsigned int i = 0;
+
+         while (strings[i] != 0)
+            puts(strings[i++]);
+
+         printf("#define PNG_CHUNK_HASH_MASK 0x%lxU\n",
+            (unsigned long)best_mask);
+         printf("#define PNG_CHUNK_HASH_C0 %u\n", best_c[0]);
+         printf("#define PNG_CHUNK_HASH_C1 %u\n", best_c[1]);
+         printf("#define PNG_CHUNK_HASH_C2 %u\n", best_c[2]);
+         printf("#define PNG_CHUNK_HASH_C3 %u\n", best_c[3]);
+
+         /* Print the hash codes of all the chunks */
+         putchar('\n');
+         print_chunks(chunks, known_chunk_count, 0, 0xffffffff, best_c,
+            best_mask, lut);
+         putchar('\n');
+         printf("#define PNG_KNOWN_CHUNK_COUNT %u\n", known_chunk_count);
+
+         while (strings[++i] != 0)
+            puts(strings[i]);
+
+         /* Now print the LUT */
+         fputs("   ", stdout);
+         {
+            unsigned int j;
+
+            for (j=0; j<=best_mask; ++j)
+            {
+               printf("%d", lut[j]);
+
+               if ((j % 16) == 15 && j < best_mask)
+                  printf(",\n   ");
+
+               else if (j < best_mask)
+                  printf(", ");
+
+               else
+                  printf("\n");
+            }
+         }
+
+         /* And the trailing text */
+         while (strings[++i] != 0)
+            puts(strings[i]);
+      }
+   }
+
+   exit(0);
+}

contrib/tools/chunkhash.h

@@ -0,0 +1,97 @@
+/* chunkhash.h -- a perfect hash code for the chunk names in png.h
+ *
+ * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ *
+ * THIS IS A MACHINE GENERATED FILE.  See contrib/tools/chunkhash.c for
+ * copyright and other information.
+ *
+ * USAGE:  To include the PNG_CHUNK_HASH macro and associated definitions:
+ *
+ * #define PNG_CHUNKHASH_DEFS
+ * #include "contrib/tools/chunkhash.h"
+ *
+ * To define the png_chunk_hash array used by the macro:
+ *
+ * #define PNG_CHUNKHASH_CODE
+ * #include "contrib/tools/chunkhash.h"
+ *
+ * One or both of the defines must be given except when building chunkhash
+ * itself.
+ */
+#ifdef PNG_CHUNKHASH_DEFS
+#ifndef PNG_CHUNKHASH_H
+#define PNG_CHUNKHASH_H
+/* A perfect hash code - returns a value 0..(PNG_KNOWN_CHUNK_COUNT-1) and is
+ * generated by the ridiculously simple program in contrib/tools/chunkhash.c
+ *
+ * The hash code used here multiplies each byte by a different constant to
+ * return a single number:
+ *
+ *    b0 * c[0] + b1 * [c1] + b2 * c[2] + b3 * c[3]
+ *
+ * The values of the constants are found by search using the a table of
+ * primes, including 0, and may be (in fact are at present) 0 for some of the
+ * bytes, the compiler is expected to optimize multiply by zero, or one!
+ *
+ * The lookup table reduces the sparse result of the hash calculation to the
+ * correct index values.  The chunks are indexed in the string order of the
+ * png_uint_32 chunk names.
+ */
+#define PNG_CHUNK_HASH_MASK 0x3fU
+#define PNG_CHUNK_HASH_C0 103
+#define PNG_CHUNK_HASH_C1 1
+#define PNG_CHUNK_HASH_C2 0
+#define PNG_CHUNK_HASH_C3 1
+
+#define PNG_CHUNK_IDAT_TAG 0
+#define PNG_CHUNK_IEND_TAG 1
+#define PNG_CHUNK_IHDR_TAG 2
+#define PNG_CHUNK_PLTE_TAG 3
+#define PNG_CHUNK_bKGD_TAG 4
+#define PNG_CHUNK_cHRM_TAG 5
+#define PNG_CHUNK_fRAc_TAG 6
+#define PNG_CHUNK_gAMA_TAG 7
+#define PNG_CHUNK_gIFg_TAG 8
+#define PNG_CHUNK_gIFt_TAG 9
+#define PNG_CHUNK_gIFx_TAG 10
+#define PNG_CHUNK_hIST_TAG 11
+#define PNG_CHUNK_iCCP_TAG 12
+#define PNG_CHUNK_iTXt_TAG 13
+#define PNG_CHUNK_oFFs_TAG 14
+#define PNG_CHUNK_pCAL_TAG 15
+#define PNG_CHUNK_pHYs_TAG 16
+#define PNG_CHUNK_sBIT_TAG 17
+#define PNG_CHUNK_sCAL_TAG 18
+#define PNG_CHUNK_sPLT_TAG 19
+#define PNG_CHUNK_sRGB_TAG 20
+#define PNG_CHUNK_sTER_TAG 21
+#define PNG_CHUNK_tEXt_TAG 22
+#define PNG_CHUNK_tIME_TAG 23
+#define PNG_CHUNK_tRNS_TAG 24
+#define PNG_CHUNK_zTXt_TAG 25
+
+#define PNG_KNOWN_CHUNK_COUNT 26
+
+extern const png_byte png_chunk_hash[PNG_CHUNK_HASH_MASK+1];
+#endif /* !PNG_CHUNKHASH_H */
+#endif /* PNG_CHUNKHASH_DEFS */
+
+#ifndef PNG_CHUNK_HASH
+#define PNG_CHUNK_HASH(chunk) (png_chunk_hash[PNG_CHUNK_HASH_MASK & (\
+      ((chunk) >> 24) * PNG_CHUNK_HASH_C0 +\
+      ((chunk) >> 16) * PNG_CHUNK_HASH_C1 +\
+      ((chunk) >>  8) * PNG_CHUNK_HASH_C2 +\
+      ((chunk)      ) * PNG_CHUNK_HASH_C3)])
+#endif
+
+#ifdef PNG_CHUNKHASH_CODE
+#ifndef PNG_CHUNKHASH_C
+#define PNG_CHUNKHASH_C
+const png_byte png_chunk_hash[PNG_CHUNK_HASH_MASK+1] = {
+   26, 3, 26, 26, 26, 26, 26, 13, 26, 26, 26, 16, 26, 26, 26, 26,
+   26, 24, 12, 26, 18, 26, 26, 26, 26, 20, 26, 17, 26, 26, 25, 15,
+   26, 8, 14, 26, 26, 22, 26, 26, 1, 19, 5, 21, 26, 26, 9, 26,
+   26, 26, 10, 7, 26, 11, 26, 0, 26, 2, 23, 26, 26, 4, 26, 6
+};
+#endif /* !PNG_CHUNKHASH_C */
+#endif /* PNG_CHUNKHASH_CODE */

contrib/tools/cvtcolor.c

@@ -1,9 +1,9 @@
 /*-
  * convert.c
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
- * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
  * United States.

contrib/tools/intgamma.sh

@@ -2,9 +2,9 @@
 #
 # intgamma.sh
 #
-# Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+# Last changed in libpng 1.6.0 [February 14, 2013]
 #
-# COPYRIGHT: Written by John Cunningham Bowler, 2012.
+# COPYRIGHT: Written by John Cunningham Bowler, 2013.
 # To the extent possible under law, the author has waived all copyright and
 # related or neighboring rights to this work.  This work is published from:
 # United States.

contrib/tools/makesRGB.c

@@ -1,8 +1,8 @@
 /* makesRGB.c -- build sRGB-to-linear and linear-to-sRGB conversion tables
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
- * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
  * United States.

contrib/tools/png-fix-itxt.c

@@ -0,0 +1,153 @@
+
+/* png-fix-itxt version 1.0.0
+ *
+ * Copyright 2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.3 [July 18, 2013]
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * Usage:            
+ *
+ *     png-fix-itxt.exe < bad.png > good.png
+ *
+ * Fixes a PNG file written with libpng-1.6.0 or 1.6.1 that has one or more
+ * uncompressed iTXt chunks.  Assumes that the actual length is greater
+ * than or equal to the value in the length byte, and that the CRC is
+ * correct for the actual length.  This program hunts for the CRC and
+ * adjusts the length byte accordingly.  It is not an error to process a
+ * PNG file that has no iTXt chunks or one that has valid iTXt chunks;
+ * such files will simply be copied.
+ *
+ * Requires zlib (for crc32 and Z_NULL); build with
+ *
+ *     gcc -O -o png-fix-itxt png-fix-itxt.c -lz
+ *
+ * If you need to handle iTXt chunks larger than 500000 kbytes you must
+ * rebuild png-fix-itxt with a larger values of MAX_LENGTH (or a smaller value
+ * if you know you will never encounter such huge iTXt chunks).
+ */
+
+#include <stdio.h>
+#include <zlib.h>
+
+#define MAX_LENGTH 500000
+
+#define GETBREAK ((unsigned char)(inchar=getchar())); if (inchar == EOF) break
+
+int
+main(void)
+{
+   unsigned int i;
+   unsigned char buf[MAX_LENGTH];
+   unsigned long crc;
+   unsigned char c;
+   int inchar;
+
+/* Skip 8-byte signature */
+   for (i=8; i; i--)
+   {
+      c=GETBREAK;
+      putchar(c);
+   }
+
+if (inchar != EOF)
+for (;;)
+ {
+   /* Read the length */
+   unsigned long length; /* must be 32 bits! */
+   c=GETBREAK; buf[0] = c; length  = c; length <<= 8;
+   c=GETBREAK; buf[1] = c; length += c; length <<= 8;
+   c=GETBREAK; buf[2] = c; length += c; length <<= 8;
+   c=GETBREAK; buf[3] = c; length += c;
+
+   /* Read the chunkname */
+   c=GETBREAK; buf[4] = c;
+   c=GETBREAK; buf[5] = c;
+   c=GETBREAK; buf[6] = c;
+   c=GETBREAK; buf[7] = c;
+
+
+   /* The iTXt chunk type expressed as integers is (105, 84, 88, 116) */
+   if (buf[4] == 105 && buf[5] == 84 && buf[6] == 88 && buf[7] == 116)
+   {
+      if (length >= MAX_LENGTH-12)
+         break;  /* To do: handle this more gracefully */
+
+      /* Initialize the CRC */
+      crc = crc32(0, Z_NULL, 0);
+
+      /* Copy the data bytes */
+      for (i=8; i < length + 12; i++)
+      {
+         c=GETBREAK; buf[i] = c;
+      }
+
+      /* Calculate the CRC */
+      crc = crc32(crc, buf+4, (uInt)length+4);
+
+      for (;;)
+      {
+        /* Check the CRC */
+        if (((crc >> 24) & 0xff) == buf[length+8] &&
+            ((crc >> 16) & 0xff) == buf[length+9] &&
+            ((crc >>  8) & 0xff) == buf[length+10] &&
+            ((crc      ) & 0xff) == buf[length+11])
+           break;
+
+        length++;
+
+        if (length >= MAX_LENGTH-12)
+           break;
+
+        c=GETBREAK;
+        buf[length+11]=c;
+
+        /* Update the CRC */
+        crc = crc32(crc, buf+7+length, 1);
+      }
+
+      /* Update length bytes */
+      buf[0] = (unsigned char)((length << 24) & 0xff);
+      buf[1] = (unsigned char)((length << 16) & 0xff);
+      buf[2] = (unsigned char)((length <<  8) & 0xff);
+      buf[3] = (unsigned char)((length      ) & 0xff);
+
+      /* Write the fixed iTXt chunk (length, name, data, crc) */
+      for (i=0; i<length+12; i++)
+         putchar(buf[i]);
+   }
+
+   else
+   {
+      /* Copy bytes that were already read (length and chunk name) */
+      for (i=0; i<8; i++)
+         putchar(buf[i]);
+
+      /* Copy data bytes and CRC */
+      for (i=8; i< length+12; i++)
+      {
+         c=GETBREAK;
+         putchar(c);
+      }
+
+      if (inchar == EOF)
+      {
+         break;
+      }
+
+   /* The IEND chunk type expressed as integers is (73, 69, 78, 68) */
+      if (buf[4] == 73 && buf[5] == 69 && buf[6] == 78 && buf[7] == 68)
+         break;
+   }
+
+   if (inchar == EOF)
+      break;
+
+   if (buf[4] == 73 && buf[5] == 69 && buf[6] == 78 && buf[7] == 68)
+     break;
+ }
+
+ return 0;
+}

contrib/tools/sRGB.h

@@ -1,9 +1,9 @@
 /*-
  * sRGB.h
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.0 [February 14, 2013]
  *
- * COPYRIGHT: Written by John Cunningham Bowler, 2012.
+ * COPYRIGHT: Written by John Cunningham Bowler, 2013.
  * To the extent possible under law, the author has waived all copyright and
  * related or neighboring rights to this work.  This work is published from:
  * United States.

example.c

@@ -2,8 +2,8 @@
 #if 0 /* in case someone actually tries to compile this */
 
 /* example.c - an example of using libpng
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
- * Maintained 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Maintained 1998-2014 Glenn Randers-Pehrson
  * Maintained 1996, 1997 Andreas Dilger)
  * Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  * To the extent possible under law, the authors have waived
@@ -52,7 +52,7 @@ int main(int argc, const char **argv)
       image.version = PNG_IMAGE_VERSION;
 
       /* The first argument is the file to read: */
-      if (png_image_begin_read_from_file(&image, argv[1]))
+      if (png_image_begin_read_from_file(&image, argv[1]) != 0)
       {
          png_bytep buffer;
 
@@ -97,7 +97,7 @@ int main(int argc, const char **argv)
           */
          if (buffer != NULL &&
             png_image_finish_read(&image, NULL/*background*/, buffer,
-               0/*row_stride*/, NULL/*colormap*/))
+               0/*row_stride*/, NULL/*colormap*/) != 0)
          {
             /* Now write the image out to the second argument.  In the write
              * call 'convert_to_8bit' allows 16-bit data to be squashed down to
@@ -105,7 +105,7 @@ int main(int argc, const char **argv)
              * to the 8-bit format.
              */
             if (png_image_write_to_file(&image, argv[2], 0/*convert_to_8bit*/,
-               buffer, 0/*row_stride*/, NULL/*colormap*/))
+               buffer, 0/*row_stride*/, NULL/*colormap*/) != 0)
             {
                /* The image has been written successfully. */
                exit(0);
@@ -188,13 +188,13 @@ int main(int argc, const char **argv)
  *
  * Don't repeatedly convert between the 8-bit and 16-bit forms.  There is
  * significant data loss when 16-bit data is converted to the 8-bit encoding and
- * the current libpng implementation of convertion to 16-bit is also
+ * the current libpng implementation of conversion to 16-bit is also
  * significantly lossy.  The latter will be fixed in the future, but the former
  * is unavoidable - the 8-bit format just doesn't have enough resolution.
  */
 
 /* If your program needs more information from the PNG data it reads, or if you
- * need to do more complex transformations, or minimise transformations, on the
+ * need to do more complex transformations, or minimize transformations, on the
  * data you read, then you must use one of the several lower level libpng
  * interfaces.
  *
@@ -405,7 +405,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    /* Expand paletted or RGB images with transparency to full alpha channels
     * so the data will be available as RGBA quartets.
     */
-   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS) != 0)
       png_set_tRNS_to_alpha(png_ptr);
 
    /* Set the background color to draw transparent and alpha images over.
@@ -417,7 +417,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
 
    png_color_16 my_background, *image_background;
 
-   if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+   if (png_get_bKGD(png_ptr, info_ptr, &image_background) != 0)
       png_set_background(png_ptr, image_background,
                          PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
    else
@@ -441,9 +441,9 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    /* If we don't have another value */
    else
    {
-      screen_gamma = 2.2;  /* A good guess for a PC monitor in a dimly
-                              lit room */
-      screen_gamma = 1.7 or 1.0;  /* A good guess for Mac systems */
+      screen_gamma = PNG_DEFAULT_sRGB;  /* A good guess for a PC monitor
+                                           in a dimly lit room */
+      screen_gamma = PNG_GAMMA_MAC_18 or 1.0; /* Good guesses for Mac systems */
    }
 
    /* Tell libpng to handle the gamma conversion for you.  The final call
@@ -454,12 +454,12 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
 
    int intent;
 
-   if (png_get_sRGB(png_ptr, info_ptr, &intent))
-      png_set_gamma(png_ptr, screen_gamma, 0.45455);
+   if (png_get_sRGB(png_ptr, info_ptr, &intent) != 0)
+      png_set_gamma(png_ptr, screen_gamma, PNG_DEFAULT_sRGB);
    else
    {
       double image_gamma;
-      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
+      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma) != 0)
          png_set_gamma(png_ptr, screen_gamma, image_gamma);
       else
          png_set_gamma(png_ptr, screen_gamma, 0.45455);
@@ -469,7 +469,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    /* Quantize RGB files down to 8 bit palette or reduce palettes
     * to the number of colors available on your screen.
     */
-   if (color_type & PNG_COLOR_MASK_COLOR)
+   if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
    {
       int num_palette;
       png_colorp palette;
@@ -484,7 +484,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
             MAX_SCREEN_COLORS, NULL, 0);
       }
       /* This reduces the image to the palette supplied in the file */
-      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette))
+      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) != 0)
       {
          png_uint_16p histogram = NULL;
 
@@ -494,7 +494,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
                         max_screen_colors, histogram, 0);
       }
    }
-#endif /* PNG_READ_QUANTIZE_SUPPORTED */
+#endif /* READ_QUANTIZE */
 
    /* Invert monochrome files to have 0 as white and 1 as black */
    png_set_invert_mono(png_ptr);
@@ -503,7 +503,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
     * [0,65535] to the original [0,7] or [0,31], or whatever range the
     * colors were originally in:
     */
-   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
+   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT) != 0)
    {
       png_color_8p sig_bit_p;
 
@@ -512,7 +512,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    }
 
    /* Flip the RGB pixels to BGR (or RGBA to BGRA) */
-   if (color_type & PNG_COLOR_MASK_COLOR)
+   if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
       png_set_bgr(png_ptr);
 
    /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
@@ -532,7 +532,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    number_passes = png_set_interlace_handling(png_ptr);
 #else
    number_passes = 1;
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 
 
    /* Optional call to gamma correct and add the background to the palette
@@ -744,7 +744,7 @@ row_callback(png_structp png_ptr, png_bytep new_row,
     * to pass the current row as new_row, and the function will combine
     * the old row and the new row.
     */
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 }
 
 end_callback(png_structp png_ptr, png_infop info)
@@ -932,7 +932,7 @@ void write_png(char *file_name /* , ... other image information ... */)
     */
 
    /* Once we write out the header, the compression type on the text
-    * chunks gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
+    * chunk gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
     * PNG_TEXT_COMPRESSION_zTXt_WR, so it doesn't get written out again
     * at the end.
     */
@@ -970,7 +970,7 @@ void write_png(char *file_name /* , ... other image information ... */)
    png_set_packswap(png_ptr);
 
    /* Turn on interlace handling if you are not using png_write_image() */
-   if (interlacing)
+   if (interlacing != 0)
       number_passes = png_set_interlace_handling(png_ptr);
 
    else

libpngpf.3

@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "April 14, 2013"
+.TH LIBPNGPF 3 "November 7, 2014"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0beta08
+libpng \- Portable Network Graphics (PNG) Reference Library 1.7.0beta41
 (private functions)
 .SH SYNOPSIS
 \fB#include \fI"pngpriv.h"

png.5

@@ -1,4 +1,4 @@
-.TH PNG 5 "April 14, 2013"
+.TH PNG 5 "November 7, 2014"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION

png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.7.0beta08 - April 14, 2013
+ * libpng version 1.7.0beta41 - November 7, 2014
  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -11,7 +11,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.7.0beta08 - April 14, 2013: Glenn
+ *   libpng versions 0.97, January 1998, through 1.7.0beta41 - November 7, 2014: Glenn
  *   See also "Contributing Authors", below.
  *
  * Note about libpng version numbers:
@@ -168,7 +168,7 @@
  *    1.5.7                   15    10507  15.so.15.7[.0]
  *    1.6.0beta01-37          16    10600  16.so.16.0[.0]
  *    1.7.0alpha01-10         17    10700  17.so.17.0[.0]
- *    1.7.0beta01-08          17    10700  17.so.17.0[.0]
+ *    1.7.0beta01-41          17    10700  17.so.17.0[.0]
  *
  *   Henceforth the source version will match the shared-library major
  *   and minor numbers; the shared-library major version number will be
@@ -200,7 +200,7 @@
  *
  * This code is released under the libpng license.
  *
- * libpng versions 1.2.6, August 15, 2004, through 1.7.0beta08, April 14, 2013, are
+ * libpng versions 1.2.6, August 15, 2004, through 1.7.0beta41, November 7, 2014, are
  * Copyright (c) 2004, 2006-2013 Glenn Randers-Pehrson, and are
  * distributed according to the same disclaimer and license as libpng-1.2.5
  * with the following individual added to the list of Contributing Authors:
@@ -312,13 +312,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    April 14, 2013
+ *    November 7, 2014
  *
  *    Since the PNG Development group is an ad-hoc body, we can't make
  *    an official declaration.
  *
  *    This is your unofficial assurance that libpng from version 0.71 and
- *    upward through 1.7.0beta08 are Y2K compliant.  It is my belief that
+ *    upward through 1.7.0beta41 are Y2K compliant.  It is my belief that
  *    earlier versions were also Y2K compliant.
  *
  *    Libpng only has two year fields.  One is a 2-byte unsigned integer
@@ -371,16 +371,18 @@
 /* This is not the place to learn how to use libpng. The file libpng-manual.txt
  * describes how to use libpng, and the file example.c summarizes it
  * with some code on which to build.  This file is useful for looking
- * at the actual function definitions and structure components.
+ * at the actual function definitions and structure components.  If that
+ * file has been stripped from your copy of libpng, you can find it at
+ * <http://www.libpng.org/pub/png/libpng-manual.txt>
  *
  * If you just need to read a PNG file and don't want to read the documentation
  * skip to the end of this file and read the section entitled 'simplified API'.
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.7.0beta08"
+#define PNG_LIBPNG_VER_STRING "1.7.0beta41"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.7.0beta08 - April 14, 2013\n"
+     " libpng version 1.7.0beta41 - November 7, 2014\n"
 
 #define PNG_LIBPNG_VER_SONUM   17
 #define PNG_LIBPNG_VER_DLLNUM  17
@@ -394,7 +396,7 @@
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
 
-#define PNG_LIBPNG_VER_BUILD  08
+#define PNG_LIBPNG_VER_BUILD  41
 
 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -464,11 +466,6 @@
 
 #ifndef PNG_VERSION_INFO_ONLY
 
-/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
 /* Version information for C files, stored in png.c.  This had better match
  * the version above.
  */
@@ -476,17 +473,138 @@ extern "C" {
 
 /* This file is arranged in several sections:
  *
- * 1. Any configuration options that can be specified by for the application
+ * 1. ISO-PNG constants and definitions; values defined by PNG and not specific
+ *    to the libpng API.
+ * 2. Any configuration options that can be specified by for the application
  *    code when it is built.  (Build time configuration is in pnglibconf.h)
- * 2. Type definitions (base types are defined in pngconf.h), structure
+ * 3. Type definitions (base types are defined in pngconf.h), structure
  *    definitions.
- * 3. Exported library functions.
- * 4. Simplified API.
+ * 4. Exported library functions.
+ * 5. Simplified API.
  *
  * The library source code has additional files (principally pngpriv.h) that
  * allow configuration of the library.
  */
-/* Section 1: run time configuration
+
+/* Section 1: ISO PNG constants and macros. */
+
+/* ISO-PNG defines byte encodings for 16 and 32-bit unsigned values and 32-bit
+ * signed values.  The macros PNG_U16, PNG_U32 and PNG_S32 return values of type
+ * (png_uint_16), (png_uint_32) and (png_int_32) which are target machine
+ * specific representations of these values, using the types defined in
+ * pngconf.h.  The macros take two or four byte values in the order in which
+ * they would occur in a PNG stream.
+ *
+ * These macros must return compile time constants if passed constant values -
+ * machine specific implementations are not permitted.  These macros are used by
+ * default in the API functions/macros png_get_uint_16, png_get_uint_32,
+ * png_get_uint_31 and png_get_int_32 declared below: these functions or macros
+ * are the correct places for machine specific implementations (such as hardware
+ * specific instructions.)
+ *
+ * The macros defined here are generic and intended to give maximum flexibility
+ * in implementation to the compiler; only PNG_S32 contains a sequence point,
+ * there are no side effects and the expressions used permit the maximum
+ * parallelization (relevant because the four bytes may be loaded in parallel.)
+ */
+#define PNG_u2(b1, b2) (((unsigned int)(b1) << 8) + (b2))
+
+#define PNG_U16(b1, b2) ((png_uint_16)PNG_u2(b1, b2))
+#define PNG_U32(b1, b2, b3, b4)\
+   (((png_uint_32)PNG_u2(b1, b2) << 16) + PNG_u2(b3, b4))
+
+/* ISO-PNG states that signed 32-bit values are stored in two's complement
+ * format.  There is no guarantee that (png_int_32) is exactly 32 bits, so the
+ * following macro tests for a negative number and generates the machine format
+ * directly by portable arithmetic operations.  The cost is that the argument
+ * 'b1' is evaluated twice.
+ */
+#define PNG_S32(b1, b2, b3, b4) ((b1) & 0x80\
+      ? -(png_int_32)((PNG_U32(b1, b2, b3, b4) ^ 0xffffffff) + 1)\
+      : (png_int_32)PNG_U32(b1, b2, b3, b4))
+
+/* Constants for known chunk types.
+ *
+ * MAINTAINERS: If you need to add a chunk, define the name here.
+ * For historical reasons these constants have the form png_<name>; i.e.
+ * the prefix is lower case.  Please use decimal values as the parameters to
+ * match the ISO PNG specification and to avoid relying on the C locale
+ * interpretation of character values.  Please keep the list sorted.
+ *
+ * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
+ * type.  In fact the specification does not express chunk types this way,
+ * however using a 32-bit value means that the chunk type can be read from the
+ * stream using exactly the same code as used for a 32-bit unsigned value and
+ * can be examined far more efficiently (using one arithmetic compare).
+ *
+ * Prior to 1.5.6 the chunk type constants were expressed as C strings.  The
+ * libpng API still uses strings for 'unknown' chunks and a macro,
+ * PNG_STRING_FROM_CHUNK, allows a string to be generated if required.  Notice
+ * that for portable code numeric values must still be used; the string "IHDR"
+ * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
+ *
+ * In 1.7.0 the definitions were made public in png.h to avoid having to
+ * duplicate the same definitions in application code.
+ *
+ * SOURCE: http://www.libpng.org/pub/png/spec/register/
+ *    "Register of PNG Public Chunks and Keywords, version 1.4.6"
+ *    "Extensions to the PNG Specification, version 1.4.0"
+ */
+#define png_IDAT PNG_U32( 73,  68,  65,  84)
+#define png_IEND PNG_U32( 73,  69,  78,  68)
+#define png_IHDR PNG_U32( 73,  72,  68,  82)
+#define png_PLTE PNG_U32( 80,  76,  84,  69)
+#define png_bKGD PNG_U32( 98,  75,  71,  68)
+#define png_cHRM PNG_U32( 99,  72,  82,  77)
+#define png_dSIG PNG_U32(100,  83,  73,  71) /* separate spec */
+#define png_fRAc PNG_U32(102,  82,  65,  99) /* registered, not defined */
+#define png_gAMA PNG_U32(103,  65,  77,  65)
+#define png_gIFg PNG_U32(103,  73,  70, 103)
+#define png_gIFt PNG_U32(103,  73,  70, 116) /* deprecated */
+#define png_gIFx PNG_U32(103,  73,  70, 120)
+#define png_hIST PNG_U32(104,  73,  83,  84)
+#define png_iCCP PNG_U32(105,  67,  67,  80)
+#define png_iTXt PNG_U32(105,  84,  88, 116)
+#define png_oFFs PNG_U32(111,  70,  70, 115)
+#define png_pCAL PNG_U32(112,  67,  65,  76)
+#define png_pHYs PNG_U32(112,  72,  89, 115)
+#define png_sBIT PNG_U32(115,  66,  73,  84)
+#define png_sCAL PNG_U32(115,  67,  65,  76)
+#define png_sPLT PNG_U32(115,  80,  76,  84)
+#define png_sRGB PNG_U32(115,  82,  71,  66)
+#define png_sTER PNG_U32(115,  84,  69,  82)
+#define png_tEXt PNG_U32(116,  69,  88, 116)
+#define png_tIME PNG_U32(116,  73,  77,  69)
+#define png_tRNS PNG_U32(116,  82,  78,  83)
+#define png_zTXt PNG_U32(122,  84,  88, 116)
+
+/* The following will work on (signed char*) strings, whereas the PNG_U32 macro
+ * used directory would fail on top-bit-set values because of the sign
+ * extension.
+ */
+#define PNG_CHUNK_FROM_STRING(s)\
+   PNG_U32(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
+
+/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
+ * signed and the argument is a (char[])  This macro will fail miserably on
+ * systems where (char) is more than 8 bits.
+ */
+#define PNG_STRING_FROM_CHUNK(s,c)\
+   (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
+   ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
+
+/* Do the same but terminate with a null character. */
+#define PNG_CSTRING_FROM_CHUNK(s,c)\
+   (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
+
+/* Test on flag values as defined in the spec (section 5.4): */
+#define PNG_CHUNK_ANCILLARY(c)    (1 & ((c) >> 29))
+#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLARY(c))
+#define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
+#define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
+#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
+
+/* Section 2: run time configuration
  * See pnglibconf.h for build time configuration
  *
  * Run time configuration allows the application to choose between
@@ -516,7 +634,12 @@ extern "C" {
  * Otherwise the calls are mapped to png_error.
  */
 
-/* Section 2: type definitions, including structures and compile time
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
+/* Section 3: type definitions, including structures and compile time
  * constants.
  * See pngconf.h for base types that vary by machine/system
  */
@@ -524,7 +647,7 @@ extern "C" {
 /* This triggers a compiler error in png.c, if png.c and png.h
  * do not agree upon the version number.
  */
-typedef char* png_libpng_version_1_7_0beta08;
+typedef char* png_libpng_version_1_7_0beta41;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -706,7 +829,8 @@ typedef png_time * png_timep;
 typedef const png_time * png_const_timep;
 typedef png_time * * png_timepp;
 
-#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#if defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) ||\
+   defined(PNG_USER_CHUNKS_SUPPORTED)
 /* png_unknown_chunk is a structure to hold queued chunks for which there is
  * no specific support.  The idea is that we can use this to queue
  * up private chunks for output even though the library doesn't actually
@@ -960,7 +1084,7 @@ typedef PNG_CALLBACK(png_voidp, *png_malloc_ptr, (png_structp,
     png_alloc_size_t));
 typedef PNG_CALLBACK(void, *png_free_ptr, (png_structp, png_voidp));
 
-/* Section 3: exported functions
+/* Section 4: exported functions
  * Here are the function definitions most commonly used.  This is not
  * the place to find out how to use libpng.  See libpng-manual.txt for the
  * full explanation, see example.c for the summary.  This just provides
@@ -1179,9 +1303,9 @@ PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
 #endif
 
 #ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-/* How the alpha channel is interpreted - this affects how the color channels of
- * a PNG file are returned when an alpha channel, or tRNS chunk in a palette
- * file, is present.
+/* How the alpha channel is interpreted - this affects how the color channels
+ * of a PNG file are returned to the calling application when an alpha channel,
+ * or a tRNS chunk in a palette file, is present.
  *
  * This has no effect on the way pixels are written into a PNG output
  * datastream. The color samples in a PNG datastream are never premultiplied
@@ -1189,33 +1313,19 @@ PNG_EXPORT(35, void, png_build_grayscale_palette, (int bit_depth,
  *
  * The default is to return data according to the PNG specification: the alpha
  * channel is a linear measure of the contribution of the pixel to the
- * corresponding composited pixel.  The gamma encoded color channels must be
- * scaled according to the contribution and to do this it is necessary to undo
+ * corresponding composited pixel, and the color channels are unassociated
+ * (not premultiplied).  The gamma encoded color channels must be scaled
+ * according to the contribution and to do this it is necessary to undo
  * the encoding, scale the color values, perform the composition and reencode
  * the values.  This is the 'PNG' mode.
  *
  * The alternative is to 'associate' the alpha with the color information by
- * storing color channel values that have been scaled by the alpha.  The
- * advantage is that the color channels can be resampled (the image can be
- * scaled) in this form.  The disadvantage is that normal practice is to store
- * linear, not (gamma) encoded, values and this requires 16-bit channels for
- * still images rather than the 8-bit channels that are just about sufficient if
- * gamma encoding is used.  In addition all non-transparent pixel values,
- * including completely opaque ones, must be gamma encoded to produce the final
- * image.  This is the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' mode (the
- * latter being the two common names for associated alpha color channels.)
+ * storing color channel values that have been scaled by the alpha.
+ * image.  These are the 'STANDARD', 'ASSOCIATED' or 'PREMULTIPLIED' modes
+ * (the latter being the two common names for associated alpha color channels).
  *
- * Since it is not necessary to perform arithmetic on opaque color values so
- * long as they are not to be resampled and are in the final color space it is
- * possible to optimize the handling of alpha by storing the opaque pixels in
- * the PNG format (adjusted for the output color space) while storing partially
- * opaque pixels in the standard, linear, format.  The accuracy required for
- * standard alpha composition is relatively low, because the pixels are
- * isolated, therefore typically the accuracy loss in storing 8-bit linear
- * values is acceptable.  (This is not true if the alpha channel is used to
- * simulate transparency over large areas - use 16 bits or the PNG mode in
- * this case!)  This is the 'OPTIMIZED' mode.  For this mode a pixel is
- * treated as opaque only if the alpha value is equal to the maximum value.
+ * For the 'OPTIMIZED' mode, a pixel is treated as opaque only if the alpha
+ * value is equal to the maximum value.
  *
  * The final choice is to gamma encode the alpha channel as well.  This is
  * broken because, in practice, no implementation that uses this choice
@@ -1242,68 +1352,7 @@ PNG_FIXED_EXPORT(228, void, png_set_alpha_mode_fixed, (png_structrp png_ptr,
 
 #if defined(PNG_GAMMA_SUPPORTED) || defined(PNG_READ_ALPHA_MODE_SUPPORTED)
 /* The output_gamma value is a screen gamma in libpng terminology: it expresses
- * how to decode the output values, not how they are encoded.  The values used
- * correspond to the normal numbers used to describe the overall gamma of a
- * computer display system; for example 2.2 for an sRGB conformant system.  The
- * values are scaled by 100000 in the _fixed version of the API (so 220000 for
- * sRGB.)
- *
- * The inverse of the value is always used to provide a default for the PNG file
- * encoding if it has no gAMA chunk and if png_set_gamma() has not been called
- * to override the PNG gamma information.
- *
- * When the ALPHA_OPTIMIZED mode is selected the output gamma is used to encode
- * opaque pixels however pixels with lower alpha values are not encoded,
- * regardless of the output gamma setting.
- *
- * When the standard Porter Duff handling is requested with mode 1 the output
- * encoding is set to be linear and the output_gamma value is only relevant
- * as a default for input data that has no gamma information.  The linear output
- * encoding will be overridden if png_set_gamma() is called - the results may be
- * highly unexpected!
- *
- * The following numbers are derived from the sRGB standard and the research
- * behind it.  sRGB is defined to be approximated by a PNG gAMA chunk value of
- * 0.45455 (1/2.2) for PNG.  The value implicitly includes any viewing
- * correction required to take account of any differences in the color
- * environment of the original scene and the intended display environment; the
- * value expresses how to *decode* the image for display, not how the original
- * data was *encoded*.
- *
- * sRGB provides a peg for the PNG standard by defining a viewing environment.
- * sRGB itself, and earlier TV standards, actually use a more complex transform
- * (a linear portion then a gamma 2.4 power law) than PNG can express.  (PNG is
- * limited to simple power laws.)  By saying that an image for direct display on
- * an sRGB conformant system should be stored with a gAMA chunk value of 45455
- * (11.3.3.2 and 11.3.3.5 of the ISO PNG specification) the PNG specification
- * makes it possible to derive values for other display systems and
- * environments.
- *
- * The Mac value is deduced from the sRGB based on an assumption that the actual
- * extra viewing correction used in early Mac display systems was implemented as
- * a power 1.45 lookup table.
- *
- * Any system where a programmable lookup table is used or where the behavior of
- * the final display device characteristics can be changed requires system
- * specific code to obtain the current characteristic.  However this can be
- * difficult and most PNG gamma correction only requires an approximate value.
- *
- * By default, if png_set_alpha_mode() is not called, libpng assumes that all
- * values are unencoded, linear, values and that the output device also has a
- * linear characteristic.  This is only very rarely correct - it is invariably
- * better to call png_set_alpha_mode() with PNG_DEFAULT_sRGB than rely on the
- * default if you don't know what the right answer is!
- *
- * The special value PNG_GAMMA_MAC_18 indicates an older Mac system (pre Mac OS
- * 10.6) which used a correction table to implement a somewhat lower gamma on an
- * otherwise sRGB system.
- *
- * Both these values are reserved (not simple gamma values) in order to allow
- * more precise correction internally in the future.
- *
- * NOTE: the following values can be passed to either the fixed or floating
- * point APIs, but the floating point API will also accept floating point
- * values.
+ * how to decode the output values, not how they are encoded.
  */
 #define PNG_DEFAULT_sRGB -1       /* sRGB gamma and color space */
 #define PNG_GAMMA_MAC_18 -2       /* Old Mac '1.8' gamma and color space */
@@ -1978,6 +2027,8 @@ PNG_EXPORTA(103, void, png_chunk_error, (png_const_structrp png_ptr,
 #else
 /* Fatal error in PNG image of libpng - can't continue */
 PNG_EXPORTA(104, void, png_err, (png_const_structrp png_ptr), PNG_NORETURN);
+#  define png_error(s1,s2) png_err(s1)
+#  define png_chunk_error(s1,s2) png_err(s1)
 #endif
 
 #ifdef PNG_WARNINGS_SUPPORTED
@@ -1988,6 +2039,9 @@ PNG_EXPORT(105, void, png_warning, (png_const_structrp png_ptr,
 /* Non-fatal error in libpng, chunk name is prepended to message. */
 PNG_EXPORT(106, void, png_chunk_warning, (png_const_structrp png_ptr,
     png_const_charp warning_message));
+#else
+#  define png_warning(s1,s2) ((void)(s1))
+#  define png_chunk_warning(s1,s2) ((void)(s1))
 #endif
 
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
@@ -2372,7 +2426,7 @@ PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
  * write.  If you wish to have chunk-specific handling on read in code that must
  * work on earlier versions you must use a user chunk callback to implement the
  * desired handling (keep or discard.)
- * 
+ *
  * NOTE: prior to 1.7.0 when a user callback returned '0', indicating that the
  * chunk had not been handled, libpng would preserve it regardless of the
  * default or per-chunk settings.  For compatibility with earlier versions
@@ -2498,11 +2552,15 @@ PNG_EXPORT(177, void, png_set_invalid, (png_const_structrp png_ptr,
 
 #ifdef PNG_INFO_IMAGE_SUPPORTED
 /* The "params" pointer is currently not used and is for future expansion. */
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 PNG_EXPORT(178, void, png_read_png, (png_structrp png_ptr, png_inforp info_ptr,
     int transforms, png_voidp params));
+#endif
+#ifdef PNG_WRITE_SUPPORTED
 PNG_EXPORT(179, void, png_write_png, (png_structrp png_ptr, png_inforp info_ptr,
     int transforms, png_voidp params));
 #endif
+#endif
 
 PNG_EXPORT(180, png_const_charp, png_get_copyright,
     (png_const_structrp png_ptr));
@@ -2740,27 +2798,18 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
 
 #ifdef PNG_USE_READ_MACROS
 /* Inline macros to do direct reads of bytes from the input buffer.
- * The png_get_int_32() routine assumes we are using two's complement
- * format for negative values, which is almost certainly true.
  */
+#  define PNG_B(ptr, offset) (((png_const_bytep)(ptr))[offset])
 #  define PNG_get_uint_32(buf) \
-     (((png_uint_32)(*(buf)) << 24) + \
-      ((png_uint_32)(*((buf) + 1)) << 16) + \
-      ((png_uint_32)(*((buf) + 2)) << 8) + \
-      ((png_uint_32)(*((buf) + 3))))
+      PNG_U32(PNG_B(buf,0), PNG_B(buf,1), PNG_B(buf,2), PNG_B(buf,3))
 
    /* From libpng-1.4.0 until 1.4.4, the png_get_uint_16 macro (but not the
     * function) incorrectly returned a value of type png_uint_32.
     */
-#  define PNG_get_uint_16(buf) \
-     ((png_uint_16) \
-      (((unsigned int)(*(buf)) << 8) + \
-       ((unsigned int)(*((buf) + 1)))))
+#  define PNG_get_uint_16(buf) PNG_U16(PNG_B(buf,0), PNG_B(buf,1))
 
 #  define PNG_get_int_32(buf) \
-     ((png_int_32)((*(buf) & 0x80) \
-      ? -((png_int_32)((png_get_uint_32(buf) ^ 0xffffffffL) + 1)) \
-      : (png_int_32)png_get_uint_32(buf)))
+      PNG_S32(PNG_B(buf,0), PNG_B(buf,1), PNG_B(buf,2), PNG_B(buf,3))
 
    /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h,
     * but defining a macro name prefixed with PNG_PREFIX.
@@ -2779,8 +2828,63 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
 #  endif
 #endif
 
+#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
+PNG_EXPORT(242, void, png_set_check_for_invalid_index,
+    (png_structrp png_ptr, int allowed));
+#  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
+PNG_EXPORT(243, int, png_get_palette_max, (png_const_structrp png_ptr,
+    png_const_inforp info_ptr));
+#  endif
+#endif /* CHECK_FOR_INVALID_INDEX */
+
 /*******************************************************************************
- *  SIMPLIFIED API
+ *  IMPLEMENTATION OPTIONS
+ *******************************************************************************
+ *
+ * Support for arbitrary implementation-specific optimizations.  The API allows
+ * particular options to be turned on or off.  'Option' is the number of the
+ * option and 'onoff' is 0 (off) or non-0 (on).  The value returned is given
+ * by the PNG_OPTION_ defines below.
+ *
+ * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions,
+ *           are detected at run time, however sometimes it may be impossible
+ *           to do this in user mode, in which case it is necessary to discover
+ *           the capabilities in an OS specific way.  Such capabilities are
+ *           listed here when libpng has support for them and must be turned
+ *           ON by the application if present.
+ *
+ * SOFTWARE: sometimes software optimizations actually result in performance
+ *           decrease on some architectures or systems, or with some sets of
+ *           PNG images.  'Software' options allow such optimizations to be
+ *           selected at run time.
+ */
+#ifdef PNG_SET_OPTION_SUPPORTED
+#ifdef PNG_ARM_NEON_API_SUPPORTED
+#  define PNG_ARM_NEON   0 /* HARDWARE: ARM Neon SIMD instructions supported */
+#endif
+#define PNG_MAXIMUM_INFLATE_WINDOW 2 /* SOFTWARE: force maximum window */
+#define PNG_OPTION_NEXT  4 /* Next option - numbers must be even */
+
+/* Return values: NOTE: there are four values and 'off' is *not* zero */
+#define PNG_OPTION_UNSET   0 /* Unset - defaults to off */
+#define PNG_OPTION_INVALID 1 /* Option number out of range */
+#define PNG_OPTION_OFF     2
+#define PNG_OPTION_ON      3
+
+PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
+   int onoff));
+#endif
+
+/*******************************************************************************
+ *  END OF HARDWARE OPTIONS
+ ******************************************************************************/
+
+/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
+ * defs
+ */
+
+/*******************************************************************************
+ *  Section 5: SIMPLIFIED API
  *******************************************************************************
  *
  * Please read the documentation in libpng-manual.txt (TODO: write said
@@ -3183,6 +3287,7 @@ PNG_EXPORT(238, void, png_image_free, (png_imagep image));
 #endif /* PNG_SIMPLIFIED_READ_SUPPORTED */
 
 #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
+#ifdef PNG_STDIO_SUPPORTED
 /* WRITE APIS
  * ----------
  * For write you must initialize a png_image structure to describe the image to
@@ -3225,65 +3330,12 @@ PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
  *
  * Note that the write API does not support interlacing or sub-8-bit pixels.
  */
+#endif /* PNG_STDIO_SUPPORTED */
 #endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */
 /*******************************************************************************
  *  END OF SIMPLIFIED API
  ******************************************************************************/
 
-#ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
-PNG_EXPORT(242, void, png_set_check_for_invalid_index,
-    (png_structrp png_ptr, int allowed));
-#  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
-PNG_EXPORT(243, int, png_get_palette_max, (png_const_structrp png_ptr,
-    png_const_inforp info_ptr));
-#  endif
-#endif /* CHECK_FOR_INVALID_INDEX */
-
-/*******************************************************************************
- *  IMPLEMENTATION OPTIONS
- *******************************************************************************
- *
- * Support for arbitrary implementation-specific optimizations.  The API allows
- * particular options to be turned on or off.  'Option' is the number of the
- * option and 'onoff' is 0 (off) or non-0 (on).  The value returned is given
- * by the PNG_OPTION_ defines below.
- *
- * HARDWARE: normally hardware capabilites, such as the Intel SSE instructions,
- *           are detected at run time, however sometimes it may be impossible
- *           to do this in user mode, in which case it is necessary to discover
- *           the capabilities in an OS specific way.  Such capabilities are
- *           listed here when libpng has support for them and must be turned
- *           ON by the application if present.
- *
- * SOFTWARE: sometimes software optimizations actually result in performance
- *           decrease on some architectures or systems, or with some sets of
- *           PNG images.  'Software' options allow such optimizations to be
- *           selected at run time.
- */
-#ifdef PNG_SET_OPTION_SUPPORTED
-#ifdef PNG_ARM_NEON_API_SUPPORTED
-#  define PNG_ARM_NEON   0 /* HARDWARE: ARM Neon SIMD instructions supported */
-#endif
-#define PNG_OPTION_NEXT  2 /* Next option - numbers must be even */
-
-/* Return values: NOTE: there are four values and 'off' is *not* zero */
-#define PNG_OPTION_UNSET   0 /* Unset - defaults to off */
-#define PNG_OPTION_INVALID 1 /* Option number out of range */
-#define PNG_OPTION_OFF     2
-#define PNG_OPTION_ON      3
-
-PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
-   int onoff));
-#endif
-
-/*******************************************************************************
- *  END OF HARDWARE OPTIONS
- ******************************************************************************/
-
-/* Maintainer: Put new public prototypes here ^, in libpng.3, and project
- * defs
- */
-
 /* The last ordinal number (this is the *last* one already used; the next
  * one to use is one more than this.)  Maintainer, remember to add an entry to
  * scripts/symbols.def as well.

pngconf.h

@@ -1,7 +1,7 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.7.0beta08 - April 14, 2013
+ * libpng version 1.7.0beta41 - November 7, 2014
  *
  * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -360,7 +360,32 @@
    * version 1.2.41.  Disabling these removes the warnings but may also produce
    * less efficient code.
    */
-#  if defined(__GNUC__)
+#  if defined(__clang__) && defined(__has_attribute)
+     /* Clang defines both __clang__ and __GNUC__. Check __clang__ first. */
+#    if !defined(PNG_USE_RESULT) && __has_attribute(__warn_unused_result__)
+#      define PNG_USE_RESULT __attribute__((__warn_unused_result__))
+#    endif
+#    if !defined(PNG_NORETURN) && __has_attribute(__noreturn__)
+#      define PNG_NORETURN __attribute__((__noreturn__))
+#    endif
+#    if !defined(PNG_ALLOCATED) && __has_attribute(__malloc__)
+#      define PNG_ALLOCATED __attribute__((__malloc__))
+#    endif
+#    if !defined(PNG_DEPRECATED) && __has_attribute(__deprecated__)
+#      define PNG_DEPRECATED __attribute__((__deprecated__))
+#    endif
+#    if !defined(PNG_PRIVATE)
+#      ifdef __has_extension
+#        if __has_extension(attribute_unavailable_with_message)
+#          define PNG_PRIVATE __attribute__((__unavailable__(\
+             "This function is not exported by libpng.")))
+#        endif
+#      endif
+#    endif
+#    ifndef PNG_RESTRICT
+#      define PNG_RESTRICT __restrict
+#    endif
+#  elif defined(__GNUC__)
 #    ifndef PNG_USE_RESULT
 #      define PNG_USE_RESULT __attribute__((__warn_unused_result__))
 #    endif
@@ -383,12 +408,12 @@
             __attribute__((__deprecated__))
 #        endif
 #      endif
-#      if ((__GNUC__ != 3) || !defined(__GNUC_MINOR__) || (__GNUC_MINOR__ >= 1))
+#      if ((__GNUC__ > 3) || !defined(__GNUC_MINOR__) || (__GNUC_MINOR__ >= 1))
 #        ifndef PNG_RESTRICT
 #          define PNG_RESTRICT __restrict
 #        endif
-#      endif /*  __GNUC__ == 3.0 */
-#    endif /*  __GNUC__ >= 3 */
+#      endif /* __GNUC__.__GNUC_MINOR__ > 3.0 */
+#    endif /* __GNUC__ >= 3 */
 
 #  elif defined(_MSC_VER)  && (_MSC_VER >= 1300)
 #    ifndef PNG_USE_RESULT
@@ -418,7 +443,7 @@
 #    ifndef PNG_RESTRICT
 #      define PNG_RESTRICT __restrict
 #    endif
-#  endif /* _MSC_VER */
+#  endif
 #endif /* PNG_PEDANTIC_WARNINGS */
 
 #ifndef PNG_DEPRECATED
@@ -439,6 +464,15 @@
 #ifndef PNG_RESTRICT
 #  define PNG_RESTRICT    /* The C99 "restrict" feature */
 #endif
+
+#ifndef PNG_FP_EXPORT     /* A floating point API. */
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+#     define PNG_FP_EXPORT(ordinal, type, name, args)\
+         PNG_EXPORT(ordinal, type, name, args);
+#  else                   /* No floating point APIs */
+#     define PNG_FP_EXPORT(ordinal, type, name, args)
+#  endif
+#endif
 #ifndef PNG_FP_EXPORT     /* A floating point API. */
 #  ifdef PNG_FLOATING_POINT_SUPPORTED
 #     define PNG_FP_EXPORT(ordinal, type, name, args)\

pngdebug.h

@@ -1,11 +1,11 @@
 
 /* pngdebug.h - Debugging macros for libpng, also used in pngtest.c
  *
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
- * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Last changed in libpng 1.6.8 [December 19, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -25,7 +25,7 @@
  *   (actually ((void)0)).
  *
  *   level: level of detail of message, starting at 0.  A level 'n'
- *          message is preceded by 'n' tab characters (not implemented
+ *          message is preceded by 'n' 3-space indentations (not implemented
  *          on Microsoft compilers unless PNG_DEBUG_FILE is also
  *          defined, to allow debug DLL compilation with no standard IO).
  *   message: a printf(3) style text string.  A trailing '\n' is added
@@ -77,32 +77,29 @@
 #      endif /* PNG_DEBUG_FILE */
 
 #      if (PNG_DEBUG > 1)
-/* Note: ["%s"m PNG_STRING_NEWLINE] probably does not work on
- * non-ISO compilers
- */
 #        ifdef __STDC__
 #          ifndef png_debug
 #            define png_debug(l,m) \
        do { \
        int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":"")))); \
+       fprintf(PNG_DEBUG_FILE,"%s" m PNG_STRING_NEWLINE,(num_tabs==1 ? "   " : \
+         (num_tabs==2 ? "      " : (num_tabs>2 ? "         " : "")))); \
        } while (0)
 #          endif
 #          ifndef png_debug1
 #            define png_debug1(l,m,p1) \
        do { \
        int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1); \
+       fprintf(PNG_DEBUG_FILE,"%s" m PNG_STRING_NEWLINE,(num_tabs==1 ? "   " : \
+         (num_tabs==2 ? "      " : (num_tabs>2 ? "         " : ""))),p1); \
        } while (0)
 #          endif
 #          ifndef png_debug2
 #            define png_debug2(l,m,p1,p2) \
        do { \
        int num_tabs=l; \
-       fprintf(PNG_DEBUG_FILE,"%s"m PNG_STRING_NEWLINE,(num_tabs==1 ? "\t" : \
-         (num_tabs==2 ? "\t\t":(num_tabs>2 ? "\t\t\t":""))),p1,p2); \
+       fprintf(PNG_DEBUG_FILE,"%s" m PNG_STRING_NEWLINE,(num_tabs==1 ? "   " : \
+         (num_tabs==2 ? "      " : (num_tabs>2 ? "         " : ""))),p1,p2);\
        } while (0)
 #          endif
 #        else /* __STDC __ */

pngerror.c

@@ -2,7 +2,7 @@
 /* pngerror.c - stub functions for i/o and memory allocation
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -27,7 +27,7 @@ static PNG_FUNCTION(void, png_default_error,PNGARG((png_const_structrp png_ptr,
 static void /* PRIVATE */
 png_default_warning PNGARG((png_const_structrp png_ptr,
    png_const_charp warning_message));
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */
 
 /* This function is called whenever there is a fatal error.  This function
  * should not be changed.  If there is a need to handle errors differently,
@@ -43,8 +43,8 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
    char msg[16];
    if (png_ptr != NULL)
    {
-      if (png_ptr->flags&
-         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+      if ((png_ptr->flags &
+         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0
       {
          if (*error_message == PNG_LITERAL_SHARP)
          {
@@ -54,7 +54,7 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
                if (error_message[offset] == ' ')
                   break;
 
-            if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+            if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0)
             {
                int i;
                for (i = 0; i < offset - 1; i++)
@@ -69,7 +69,7 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
 
       else
       {
-         if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+         if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0)
          {
             msg[0] = '0';
             msg[1] = '\0';
@@ -103,7 +103,7 @@ png_err,(png_const_structrp png_ptr),PNG_NORETURN)
       use the default handler, which will not return. */
    png_default_error(png_ptr, "");
 }
-#endif /* PNG_ERROR_TEXT_SUPPORTED */
+#endif /* ERROR_TEXT */
 
 /* Utility to safely appends strings to a buffer.  This never errors out so
  * error checking is not required in the caller.
@@ -152,7 +152,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
          case PNG_NUMBER_FORMAT_fixed:
             /* Needs five digits (the fraction) */
             mincount = 5;
-            if (output || number % 10 != 0)
+            if (output != 0 || number % 10 != 0)
             {
                *--end = digits[number % 10];
                output = 1;
@@ -163,7 +163,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
          case PNG_NUMBER_FORMAT_02u:
             /* Expects at least 2 digits. */
             mincount = 2;
-            /* fall through */
+            /* FALL THROUGH */
 
          case PNG_NUMBER_FORMAT_u:
             *--end = digits[number % 10];
@@ -173,7 +173,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
          case PNG_NUMBER_FORMAT_02x:
             /* This format expects at least two digits */
             mincount = 2;
-            /* fall through */
+            /* FALL THROUGH */
 
          case PNG_NUMBER_FORMAT_x:
             *--end = digits[number & 0xf];
@@ -189,13 +189,13 @@ png_format_number(png_const_charp start, png_charp end, int format,
       ++count;
 
       /* Float a fixed number here: */
-      if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start)
+      if ((format == PNG_NUMBER_FORMAT_fixed) && (count == 5) && (end > start))
       {
          /* End of the fraction, but maybe nothing was output?  In that case
           * drop the decimal point.  If the number is a true zero handle that
           * here.
           */
-         if (output)
+         if (output != 0)
             *--end = '.';
          else if (number == 0) /* and !output */
             *--end = '0';
@@ -219,8 +219,8 @@ png_warning(png_const_structrp png_ptr, png_const_charp warning_message)
    if (png_ptr != NULL)
    {
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   if (png_ptr->flags&
-       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+   if ((png_ptr->flags &
+       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0)
 #endif
       {
          if (*warning_message == PNG_LITERAL_SHARP)
@@ -355,13 +355,13 @@ png_formatted_warning(png_const_structrp png_ptr, png_warning_parameters p,
     */
    png_warning(png_ptr, msg);
 }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */
 
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
 void PNGAPI
 png_benign_error(png_const_structrp png_ptr, png_const_charp error_message)
 {
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
+   if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0)
    {
 #     ifdef PNG_READ_SUPPORTED
          if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
@@ -382,24 +382,36 @@ png_benign_error(png_const_structrp png_ptr, png_const_charp error_message)
 #     endif
       png_error(png_ptr, error_message);
    }
+
+#  ifndef PNG_ERROR_TEXT_SUPPORTED
+      PNG_UNUSED(error_message)
+#  endif
 }
 
 void /* PRIVATE */
 png_app_warning(png_const_structrp png_ptr, png_const_charp error_message)
 {
-  if (png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN)
+  if ((png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN) != 0)
      png_warning(png_ptr, error_message);
   else
      png_error(png_ptr, error_message);
+
+#  ifndef PNG_ERROR_TEXT_SUPPORTED
+      PNG_UNUSED(error_message)
+#  endif
 }
 
 void /* PRIVATE */
 png_app_error(png_const_structrp png_ptr, png_const_charp error_message)
 {
-  if (png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN)
+  if ((png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN) != 0)
      png_warning(png_ptr, error_message);
   else
      png_error(png_ptr, error_message);
+
+#  ifndef PNG_ERROR_TEXT_SUPPORTED
+      PNG_UNUSED(error_message)
+#  endif
 }
 #endif /* BENIGN_ERRORS */
 
@@ -416,7 +428,8 @@ static PNG_CONST char png_digit[16] = {
 };
 
 #define PNG_MAX_ERROR_TEXT 196 /* Currently limited be profile_error in png.c */
-#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
+#if defined(PNG_WARNINGS_SUPPORTED) || \
+   (defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED))
 static void /* PRIVATE */
 png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp
     error_message)
@@ -429,7 +442,7 @@ png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp
       int c = (int)(chunk_name >> ishift) & 0xff;
 
       ishift -= 8;
-      if (isnonalpha(c))
+      if (isnonalpha(c) != 0)
       {
          buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET;
          buffer[iout++] = png_digit[(c & 0xf0) >> 4];
@@ -460,7 +473,7 @@ png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp
       buffer[iout] = '\0';
    }
 }
-#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */
+#endif /* WARNINGS || ERROR_TEXT */
 
 #if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
 PNG_FUNCTION(void,PNGAPI
@@ -477,7 +490,7 @@ png_chunk_error,(png_const_structrp png_ptr, png_const_charp error_message),
       png_error(png_ptr, msg);
    }
 }
-#endif /* PNG_READ_SUPPORTED && PNG_ERROR_TEXT_SUPPORTED */
+#endif /* READ && ERROR_TEXT */
 
 #ifdef PNG_WARNINGS_SUPPORTED
 void PNGAPI
@@ -493,7 +506,7 @@ png_chunk_warning(png_const_structrp png_ptr, png_const_charp warning_message)
       png_warning(png_ptr, msg);
    }
 }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */
 
 #ifdef PNG_READ_SUPPORTED
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
@@ -501,23 +514,31 @@ void PNGAPI
 png_chunk_benign_error(png_const_structrp png_ptr, png_const_charp
     error_message)
 {
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
+   if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0)
       png_chunk_warning(png_ptr, error_message);
 
    else
       png_chunk_error(png_ptr, error_message);
+
+#  ifndef PNG_ERROR_TEXT_SUPPORTED
+      PNG_UNUSED(error_message)
+#  endif
 }
 #endif
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ */
 
 void /* PRIVATE */
 png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
 {
+#  ifndef PNG_WARNINGS_SUPPORTED
+      PNG_UNUSED(message)
+#  endif
+
    /* This is always supported, but for just read or just write it
     * unconditionally does the right thing.
     */
 #  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
 #  endif
 
 #  ifdef PNG_READ_SUPPORTED
@@ -531,7 +552,7 @@ png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
 #  endif
 
 #  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
-      else if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
+      else if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
 #  endif
 
 #  ifdef PNG_WRITE_SUPPORTED
@@ -562,11 +583,12 @@ png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN)
    char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT];
    memcpy(msg, fixed_message, fixed_message_ln);
    iin = 0;
-   if (name != NULL) while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0)
-   {
-      msg[fixed_message_ln + iin] = name[iin];
-      ++iin;
-   }
+   if (name != NULL)
+      while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0)
+      {
+         msg[fixed_message_ln + iin] = name[iin];
+         ++iin;
+      }
    msg[fixed_message_ln + iin] = 0;
    png_error(png_ptr, msg);
 }
@@ -742,8 +764,12 @@ PNG_FUNCTION(void,PNGAPI
 png_longjmp,(png_const_structrp png_ptr, int val),PNG_NORETURN)
 {
 #ifdef PNG_SETJMP_SUPPORTED
-   if (png_ptr && png_ptr->longjmp_fn && png_ptr->jmp_buf_ptr)
+   if (png_ptr != NULL && png_ptr->longjmp_fn != NULL &&
+       png_ptr->jmp_buf_ptr != NULL)
       png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val);
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(val)
 #endif
 
    /* If control reaches this point, png_longjmp() must not return. The only
@@ -808,7 +834,7 @@ png_default_warning(png_const_structrp png_ptr, png_const_charp warning_message)
 #endif
    PNG_UNUSED(png_ptr) /* Make compiler happy */
 }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */
 
 /* This function is called when the application wants to use another method
  * of handling errors and warnings.  Note that the error function MUST NOT
@@ -865,8 +891,8 @@ png_set_strip_error_numbers(png_structrp png_ptr, png_uint_32 strip_mode)
     * possible to implement without setjmp support just so long as there is some
     * way to handle the error return here:
     */
-PNG_FUNCTION(void /* PRIVATE */,
-png_safe_error,(png_structp png_nonconst_ptr, png_const_charp error_message),
+PNG_FUNCTION(void /* PRIVATE */, (PNGCBAPI
+png_safe_error),(png_structp png_nonconst_ptr, png_const_charp error_message),
    PNG_NORETURN)
 {
    const png_const_structrp png_ptr = png_nonconst_ptr;
@@ -901,7 +927,7 @@ png_safe_error,(png_structp png_nonconst_ptr, png_const_charp error_message),
 }
 
 #ifdef PNG_WARNINGS_SUPPORTED
-void /* PRIVATE */
+void /* PRIVATE */ PNGCBAPI
 png_safe_warning(png_structp png_nonconst_ptr, png_const_charp warning_message)
 {
    const png_const_structrp png_ptr = png_nonconst_ptr;
@@ -928,7 +954,7 @@ png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg)
    saved_error_buf = image->opaque->error_buf;
    result = setjmp(safe_jmpbuf) == 0;
 
-   if (result)
+   if (result != 0)
    {
 
       image->opaque->error_buf = safe_jmpbuf;
@@ -938,10 +964,10 @@ png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg)
    image->opaque->error_buf = saved_error_buf;
 
    /* And do the cleanup prior to any failure return. */
-   if (!result)
+   if (result == 0)
       png_image_free(image);
 
    return result;
 }
 #endif /* SIMPLIFIED READ/WRITE */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* READ || WRITE */

pngget.c

@@ -1,8 +1,8 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * Last changed in libpng 1.6.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -116,7 +116,8 @@ png_get_x_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp
    info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
       {
          png_debug1(1, "in %s retrieval function",
              "png_get_x_pixels_per_meter");
@@ -124,6 +125,9 @@ png_get_x_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp
          if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
             return (info_ptr->x_pixels_per_unit);
       }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -134,7 +138,8 @@ png_get_y_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp
     info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
       png_debug1(1, "in %s retrieval function",
           "png_get_y_pixels_per_meter");
@@ -142,6 +147,9 @@ png_get_y_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp
       if (info_ptr->phys_unit_type == PNG_RESOLUTION_METER)
          return (info_ptr->y_pixels_per_unit);
    }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -151,7 +159,8 @@ png_uint_32 PNGAPI
 png_get_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter");
 
@@ -159,6 +168,9 @@ png_get_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp info_ptr)
           info_ptr->x_pixels_per_unit == info_ptr->y_pixels_per_unit)
          return (info_ptr->x_pixels_per_unit);
    }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -170,7 +182,8 @@ png_get_pixel_aspect_ratio(png_const_structrp png_ptr, png_const_inforp
    info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");
 
@@ -193,10 +206,11 @@ png_get_pixel_aspect_ratio_fixed(png_const_structrp png_ptr,
     png_const_inforp info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)
-       && info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0
-       && info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX
-       && info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0 &&
+       info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0 &&
+       info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX &&
+       info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
    {
       png_fixed_point res;
 
@@ -206,7 +220,7 @@ png_get_pixel_aspect_ratio_fixed(png_const_structrp png_ptr,
        * range of 0..2^31-1; otherwise the cast might overflow.
        */
       if (png_muldiv(&res, (png_int_32)info_ptr->y_pixels_per_unit, PNG_FP_1,
-          (png_int_32)info_ptr->x_pixels_per_unit))
+          (png_int_32)info_ptr->x_pixels_per_unit) != 0)
          return res;
    }
 #else
@@ -222,13 +236,17 @@ png_int_32 PNGAPI
 png_get_x_offset_microns(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");
 
       if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
          return (info_ptr->x_offset);
    }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -238,13 +256,17 @@ png_int_32 PNGAPI
 png_get_y_offset_microns(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");
 
       if (info_ptr->offset_unit_type == PNG_OFFSET_MICROMETER)
          return (info_ptr->y_offset);
    }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -254,13 +276,17 @@ png_int_32 PNGAPI
 png_get_x_offset_pixels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");
 
       if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
          return (info_ptr->x_offset);
    }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -270,13 +296,17 @@ png_int_32 PNGAPI
 png_get_y_offset_pixels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");
 
       if (info_ptr->offset_unit_type == PNG_OFFSET_PIXEL)
          return (info_ptr->y_offset);
    }
+#else
+   PNG_UNUSED(png_ptr)
+   PNG_UNUSED(info_ptr)
 #endif
 
    return (0);
@@ -307,7 +337,7 @@ ppi_from_ppm(png_uint_32 ppm)
     */
    png_fixed_point result;
    if (ppm <= PNG_UINT_31_MAX && png_muldiv(&result, (png_int_32)ppm, 127,
-       5000))
+       5000) != 0)
       return result;
 
    /* Overflow. */
@@ -393,7 +423,8 @@ png_get_pHYs_dpi(png_const_structrp png_ptr, png_const_inforp info_ptr,
 {
    png_uint_32 retval = 0;
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
       png_debug1(1, "in %s retrieval function", "pHYs");
 
@@ -424,12 +455,12 @@ png_get_pHYs_dpi(png_const_structrp png_ptr, png_const_inforp info_ptr,
 
    return (retval);
 }
-#endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
+#endif /* pHYs */
+#endif  /* INCH_CONVERSIONS */
 
 /* png_get_channels really belongs in here, too, but it's been around longer */
 
-#endif  /* PNG_EASY_ACCESS_SUPPORTED */
+#endif  /* EASY_ACCESS */
 
 
 png_byte PNGAPI
@@ -457,8 +488,9 @@ png_uint_32 PNGAPI
 png_get_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
    png_color_16p *background)
 {
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
-       && background != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_bKGD) != 0 &&
+       background != NULL)
    {
       png_debug1(1, "in %s retrieval function", "bKGD");
 
@@ -488,7 +520,7 @@ png_get_cHRM(png_const_structrp png_ptr, png_const_inforp info_ptr,
     * consistent.
     */
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
       png_debug1(1, "in %s retrieval function", "cHRM");
 
@@ -529,7 +561,7 @@ png_get_cHRM_XYZ(png_const_structrp png_ptr, png_const_inforp info_ptr,
    double *blue_Z)
 {
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
       png_debug1(1, "in %s retrieval function", "cHRM_XYZ(float)");
 
@@ -577,7 +609,7 @@ png_get_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
     png_fixed_point *int_blue_Z)
 {
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
       png_debug1(1, "in %s retrieval function", "cHRM_XYZ");
 
@@ -614,7 +646,7 @@ png_get_cHRM_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
    png_debug1(1, "in %s retrieval function", "cHRM");
 
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
    {
       if (white_x != NULL)
          *white_x = info_ptr->colorspace.end_points_xy.whitex;
@@ -649,7 +681,7 @@ png_get_gAMA_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
    png_debug1(1, "in %s retrieval function", "gAMA");
 
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) &&
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
       file_gamma != NULL)
    {
       *file_gamma = info_ptr->colorspace.gamma;
@@ -668,7 +700,7 @@ png_get_gAMA(png_const_structrp png_ptr, png_const_inforp info_ptr,
    png_debug1(1, "in %s retrieval function", "gAMA(float)");
 
    if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) &&
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
       file_gamma != NULL)
    {
       *file_gamma = png_float(png_ptr, info_ptr->colorspace.gamma,
@@ -688,8 +720,8 @@ png_get_sRGB(png_const_structrp png_ptr, png_const_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "sRGB");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
-       && file_srgb_intent != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+      (info_ptr->valid & PNG_INFO_sRGB) != 0 && file_srgb_intent != NULL)
    {
       *file_srgb_intent = info_ptr->colorspace.rendering_intent;
       return (PNG_INFO_sRGB);
@@ -707,9 +739,10 @@ png_get_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "iCCP");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
-       && name != NULL && compression_type != NULL && profile != NULL &&
-		 proflen != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_iCCP) != 0 &&
+       name != NULL && compression_type != NULL && profile != NULL &&
+           proflen != NULL)
    {
       *name = info_ptr->iccp_name;
       *profile = info_ptr->iccp_profile;
@@ -747,8 +780,8 @@ png_get_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "hIST");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
-       && hist != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_hIST) != 0 && hist != NULL)
    {
       *hist = info_ptr->hist;
       return (PNG_INFO_hIST);
@@ -803,8 +836,9 @@ png_get_oFFs(png_const_structrp png_ptr, png_const_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "oFFs");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
-       && offset_x != NULL && offset_y != NULL && unit_type != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0 &&
+       offset_x != NULL && offset_y != NULL && unit_type != NULL)
    {
       *offset_x = info_ptr->x_offset;
       *offset_y = info_ptr->y_offset;
@@ -824,8 +858,9 @@ png_get_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "pCAL");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
-       && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pCAL) != 0 &&
+       purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
        nparams != NULL && units != NULL && params != NULL)
    {
       *purpose = info_ptr->pcal_purpose;
@@ -850,7 +885,7 @@ png_get_sCAL_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, png_fixed_point *width, png_fixed_point *height)
 {
    if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
+       (info_ptr->valid & PNG_INFO_sCAL) != 0)
    {
       *unit = info_ptr->scal_unit;
       /*TODO: make this work without FP support; the API is currently eliminated
@@ -873,7 +908,7 @@ png_get_sCAL(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, double *width, double *height)
 {
    if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
+       (info_ptr->valid & PNG_INFO_sCAL) != 0)
    {
       *unit = info_ptr->scal_unit;
       *width = atof(info_ptr->scal_s_width);
@@ -891,7 +926,7 @@ png_get_sCAL_s(png_const_structrp png_ptr, png_const_inforp info_ptr,
     int *unit, png_charpp width, png_charpp height)
 {
    if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
+       (info_ptr->valid & PNG_INFO_sCAL) != 0)
    {
       *unit = info_ptr->scal_unit;
       *width = info_ptr->scal_s_width;
@@ -913,7 +948,7 @@ png_get_pHYs(png_const_structrp png_ptr, png_const_inforp info_ptr,
    png_debug1(1, "in %s retrieval function", "pHYs");
 
    if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_pHYs))
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
    {
       if (res_x != NULL)
       {
@@ -944,8 +979,8 @@ png_get_PLTE(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "PLTE");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
-       && palette != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_PLTE) != 0 && palette != NULL)
    {
       *palette = info_ptr->palette;
       *num_palette = info_ptr->num_palette;
@@ -963,8 +998,8 @@ png_get_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "sBIT");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
-       && sig_bit != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_sBIT) != 0 && sig_bit != NULL)
    {
       *sig_bit = &(info_ptr->sig_bit);
       return (PNG_INFO_sBIT);
@@ -1007,8 +1042,8 @@ png_get_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    png_debug1(1, "in %s retrieval function", "tIME");
 
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
-       && mod_time != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_tIME) != 0 && mod_time != NULL)
    {
       *mod_time = &(info_ptr->mod_time);
       return (PNG_INFO_tIME);
@@ -1024,7 +1059,8 @@ png_get_tRNS(png_const_structrp png_ptr, png_inforp info_ptr,
     png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
 {
    png_uint_32 retval = 0;
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_tRNS) != 0)
    {
       png_debug1(1, "in %s retrieval function", "tRNS");
 
@@ -1101,7 +1137,7 @@ png_get_compression_buffer_size(png_const_structrp png_ptr)
       return 0;
 
 #  ifdef PNG_WRITE_SUPPORTED
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
 #  endif
    {
 #     ifdef PNG_SEQUENTIAL_READ_SUPPORTED
@@ -1145,7 +1181,7 @@ png_get_chunk_malloc_max (png_const_structrp png_ptr)
 {
    return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
 }
-#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+#endif /* ?SET_USER_LIMITS */
 
 /* These functions were added to libpng 1.4.0 */
 #ifdef PNG_IO_STATE_SUPPORTED
@@ -1160,7 +1196,7 @@ png_get_io_chunk_type (png_const_structrp png_ptr)
 {
    return png_ptr->chunk_name;
 }
-#endif /* ?PNG_IO_STATE_SUPPORTED */
+#endif /* ?IO_STATE */
 
 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
 #  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
@@ -1175,4 +1211,4 @@ png_get_palette_max(png_const_structrp png_ptr, png_const_inforp info_ptr)
 #  endif
 #endif
 
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* READ || WRITE */

pnginfo.h

@@ -1,11 +1,11 @@
 
 /* pnginfo.h - header file for PNG reference library
  *
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2013 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
- * Last changed in libpng 1.5.0 [January 6, 2011]
+ * Last changed in libpng 1.6.1 [March 28, 2013]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -223,13 +223,17 @@ defined(PNG_READ_BACKGROUND_SUPPORTED)
 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
    /* Storage for unknown chunks that the library doesn't recognize. */
    png_unknown_chunkp unknown_chunks;
+
+   /* The type of this field is limited by the type of 
+    * png_struct::user_chunk_cache_max, else overflow can occur.
+    */
    int                unknown_chunks_num;
 #endif
 
 #ifdef PNG_sPLT_SUPPORTED
    /* Data on sPLT chunks (there may be more than one). */
    png_sPLT_tp splt_palettes;
-   int         splt_palettes_num;
+   int         splt_palettes_num; /* Match type returned by png_get API */
 #endif
 
 #ifdef PNG_sCAL_SUPPORTED

pngmem.c

@@ -2,7 +2,7 @@
 /* pngmem.c - stub functions for memory allocation
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -73,9 +73,10 @@ png_malloc_base,(png_const_structrp png_ptr, png_alloc_size_t size),
     * to implement a user memory handler.  This checks to be sure it isn't
     * called with big numbers.
     */
-#ifdef PNG_USER_MEM_SUPPORTED
+#ifndef PNG_USER_MEM_SUPPORTED
    PNG_UNUSED(png_ptr)
 #endif
+
    if (size > 0 && size <= PNG_SIZE_MAX
 #     ifdef PNG_MAX_MALLOC_64K
          && size <= 65536U
@@ -95,6 +96,8 @@ png_malloc_base,(png_const_structrp png_ptr, png_alloc_size_t size),
       return NULL;
 }
 
+#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
+   defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
 /* This is really here only to work round a spurious warning in GCC 4.6 and 4.7
  * that arises because of the checks in png_realloc_array that are repeated in
  * png_malloc_array.
@@ -155,14 +158,17 @@ png_realloc_array,(png_structrp png_ptr, png_const_voidp old_array,
    }
 
 #ifdef PNG_READ_SUPPORTED
+# ifdef PNG_USER_LIMITS_SUPPORTED
    /* The potential overflow case.  Set the cache counter so libpng will
     * not make any more attempts
     */
    png_ptr->user_chunk_cache_max = 2;
+# endif
 #endif
 
    return NULL; /* error */
 }
+#endif /* TEXT || sPLT || STORE_UNKNOWN_CHUNKS */
 
 /* Various functions that have different error handling are derived from this.
  * png_malloc always exists, but if PNG_USER_MEM_SUPPORTED is defined a separate
@@ -219,7 +225,7 @@ png_free(png_const_structrp png_ptr, png_voidp ptr)
       png_ptr->free_fn(png_constcast(png_structrp,png_ptr), ptr);
 
    else
-#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* USER_MEM */
       free(ptr);
 }
 
@@ -251,5 +257,5 @@ png_get_mem_ptr(png_const_structrp png_ptr)
 
    return png_ptr->mem_ptr;
 }
-#endif /* PNG_USER_MEM_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* USER_MEM */
+#endif /* READ || WRITE */

pngpread.c

@@ -2,7 +2,7 @@
 /* pngpread.c - read a png file in push mode
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -26,6 +26,13 @@
 #define PNG_READ_iTXt_MODE  7
 #define PNG_ERROR_MODE      8
 
+#define PNG_PUSH_SAVE_BUFFER_IF_FULL \
+if (png_ptr->push_length + 4 > png_ptr->buffer_size) \
+   { png_push_save_buffer(png_ptr); return; }
+#define PNG_PUSH_SAVE_BUFFER_IF_LT(N) \
+if (png_ptr->buffer_size < N) \
+   { png_push_save_buffer(png_ptr); return; }
+
 void PNGAPI
 png_process_data(png_structrp png_ptr, png_inforp info_ptr,
     png_bytep buffer, png_size_t buffer_size)
@@ -46,10 +53,10 @@ png_process_data_pause(png_structrp png_ptr, int save)
 {
    if (png_ptr != NULL)
    {
-      /* It's easiest for the caller if we do the save, then the caller doesn't
+      /* It's easiest for the caller if we do the save; then the caller doesn't
        * have to supply the same data again:
        */
-      if (save)
+      if (save != 0)
          png_push_save_buffer(png_ptr);
       else
       {
@@ -151,7 +158,7 @@ png_process_some_data(png_structrp png_ptr, png_inforp info_ptr)
 void /* PRIVATE */
 png_push_read_sig(png_structrp png_ptr, png_inforp info_ptr)
 {
-   png_size_t num_checked = png_ptr->sig_bytes,
+   png_size_t num_checked = png_ptr->sig_bytes, /* SAFE, does not exceed 8 */ 
              num_to_check = 8 - num_checked;
 
    if (png_ptr->buffer_size < num_to_check)
@@ -185,27 +192,22 @@ void /* PRIVATE */
 png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 {
    png_uint_32 chunk_name;
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
    int keep; /* unknown handling method */
 #endif
 
-   /* First we make sure we have enough data for the 4 byte chunk name
-    * and the 4 byte chunk length before proceeding with decoding the
+   /* First we make sure we have enough data for the 4-byte chunk name
+    * and the 4-byte chunk length before proceeding with decoding the
     * chunk data.  To fully decode each of these chunks, we also make
-    * sure we have enough data in the buffer for the 4 byte CRC at the
+    * sure we have enough data in the buffer for the 4-byte CRC at the
     * end of every chunk (except IDAT, which is handled separately).
     */
-   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+   if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
    {
       png_byte chunk_length[4];
       png_byte chunk_tag[4];
 
-      if (png_ptr->buffer_size < 8)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_LT(8)
       png_push_fill_buffer(png_ptr, chunk_length, 4);
       png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
       png_reset_crc(png_ptr);
@@ -219,28 +221,29 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 
    if (chunk_name == png_IDAT)
    {
-      if (png_ptr->mode & PNG_AFTER_IDAT)
+      if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
          png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
 
       /* If we reach an IDAT chunk, this means we have read all of the
        * header chunks, and we can start reading the image (or if this
        * is called after the image has been read - we have an error).
        */
-      if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      if ((png_ptr->mode & PNG_HAVE_IHDR) == 0)
          png_error(png_ptr, "Missing IHDR before IDAT");
 
       else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-          !(png_ptr->mode & PNG_HAVE_PLTE))
+          (png_ptr->mode & PNG_HAVE_PLTE) == 0)
          png_error(png_ptr, "Missing PLTE before IDAT");
 
       png_ptr->mode |= PNG_HAVE_IDAT;
+      png_ptr->process_mode = PNG_READ_IDAT_MODE;
 
-      if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+      if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
          if (png_ptr->push_length == 0)
             return;
 
-      if (png_ptr->mode & PNG_AFTER_IDAT)
-         png_benign_error(png_ptr, "Too many IDATs found");
+      if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
+         png_benign_error(png_ptr, "Too many IDATs found[p]");
    }
 
    if (chunk_name == png_IHDR)
@@ -248,52 +251,33 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
       if (png_ptr->push_length != 13)
          png_error(png_ptr, "Invalid IHDR length");
 
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_IHDR(png_ptr, info_ptr, png_ptr->push_length);
    }
 
    else if (chunk_name == png_IEND)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_IEND(png_ptr, info_ptr, png_ptr->push_length);
 
       png_ptr->process_mode = PNG_READ_DONE_MODE;
       png_push_have_end(png_ptr, info_ptr);
    }
 
-#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
    else if ((keep = png_chunk_unknown_handling(png_ptr, chunk_name)) != 0)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length, keep);
 
       if (chunk_name == png_PLTE)
          png_ptr->mode |= PNG_HAVE_PLTE;
    }
-
 #endif
+
    else if (chunk_name == png_PLTE)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -312,12 +296,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_gAMA_SUPPORTED
    else if (png_ptr->chunk_name == png_gAMA)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_gAMA(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -325,12 +304,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_sBIT_SUPPORTED
    else if (png_ptr->chunk_name == png_sBIT)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_sBIT(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -338,12 +312,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_cHRM_SUPPORTED
    else if (png_ptr->chunk_name == png_cHRM)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_cHRM(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -351,12 +320,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_sRGB_SUPPORTED
    else if (chunk_name == png_sRGB)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_sRGB(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -364,12 +328,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_iCCP_SUPPORTED
    else if (png_ptr->chunk_name == png_iCCP)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_iCCP(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -377,12 +336,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_sPLT_SUPPORTED
    else if (chunk_name == png_sPLT)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_sPLT(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -390,12 +344,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_tRNS_SUPPORTED
    else if (chunk_name == png_tRNS)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_tRNS(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -403,12 +352,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_bKGD_SUPPORTED
    else if (chunk_name == png_bKGD)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_bKGD(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -416,12 +360,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_hIST_SUPPORTED
    else if (chunk_name == png_hIST)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_hIST(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -429,12 +368,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_pHYs_SUPPORTED
    else if (chunk_name == png_pHYs)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_pHYs(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -442,12 +376,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_oFFs_SUPPORTED
    else if (chunk_name == png_oFFs)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_oFFs(png_ptr, info_ptr, png_ptr->push_length);
    }
 #endif
@@ -455,12 +384,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_pCAL_SUPPORTED
    else if (chunk_name == png_pCAL)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_pCAL(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -468,12 +392,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_sCAL_SUPPORTED
    else if (chunk_name == png_sCAL)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_sCAL(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -481,12 +400,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_tIME_SUPPORTED
    else if (chunk_name == png_tIME)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_tIME(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -494,12 +408,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_tEXt_SUPPORTED
    else if (chunk_name == png_tEXt)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_tEXt(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -507,12 +416,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_zTXt_SUPPORTED
    else if (chunk_name == png_zTXt)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_zTXt(png_ptr, info_ptr, png_ptr->push_length);
    }
 
@@ -520,23 +424,14 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_iTXt_SUPPORTED
    else if (chunk_name == png_iTXt)
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_iTXt(png_ptr, info_ptr, png_ptr->push_length);
    }
-
 #endif
+
    else
    {
-      if (png_ptr->push_length + 4 > png_ptr->buffer_size)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
+      PNG_PUSH_SAVE_BUFFER_IF_FULL
       png_handle_unknown(png_ptr, info_ptr, png_ptr->push_length,
          PNG_HANDLE_CHUNK_AS_DEFAULT);
    }
@@ -554,7 +449,7 @@ png_push_crc_skip(png_structrp png_ptr, png_uint_32 skip)
 void /* PRIVATE */
 png_push_crc_finish(png_structrp png_ptr)
 {
-   if (png_ptr->skip_length && png_ptr->save_buffer_size)
+   if (png_ptr->skip_length != 0 && png_ptr->save_buffer_size != 0)
    {
       png_size_t save_size = png_ptr->save_buffer_size;
       png_uint_32 skip_length = png_ptr->skip_length;
@@ -578,7 +473,7 @@ png_push_crc_finish(png_structrp png_ptr)
       png_ptr->save_buffer_size -= save_size;
       png_ptr->save_buffer_ptr += save_size;
    }
-   if (png_ptr->skip_length && png_ptr->current_buffer_size)
+   if (png_ptr->skip_length != 0 && png_ptr->current_buffer_size != 0)
    {
       png_size_t save_size = png_ptr->current_buffer_size;
       png_uint_32 skip_length = png_ptr->skip_length;
@@ -599,14 +494,9 @@ png_push_crc_finish(png_structrp png_ptr)
       png_ptr->current_buffer_size -= save_size;
       png_ptr->current_buffer_ptr += save_size;
    }
-   if (!png_ptr->skip_length)
+   if (png_ptr->skip_length == 0)
    {
-      if (png_ptr->buffer_size < 4)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_LT(4)
       png_crc_finish(png_ptr, 0);
       png_ptr->process_mode = PNG_READ_CHUNK_MODE;
    }
@@ -621,7 +511,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
       return;
 
    ptr = buffer;
-   if (png_ptr->save_buffer_size)
+   if (png_ptr->save_buffer_size != 0)
    {
       png_size_t save_size;
 
@@ -638,7 +528,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
       png_ptr->save_buffer_size -= save_size;
       png_ptr->save_buffer_ptr += save_size;
    }
-   if (length && png_ptr->current_buffer_size)
+   if (length != 0 && png_ptr->current_buffer_size != 0)
    {
       png_size_t save_size;
 
@@ -658,7 +548,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
 void /* PRIVATE */
 png_push_save_buffer(png_structrp png_ptr)
 {
-   if (png_ptr->save_buffer_size)
+   if (png_ptr->save_buffer_size != 0)
    {
       if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
       {
@@ -694,11 +584,13 @@ png_push_save_buffer(png_structrp png_ptr)
       if (png_ptr->save_buffer == NULL)
       {
          png_free(png_ptr, old_buffer);
+         old_buffer = NULL;
          png_error(png_ptr, "Insufficient memory for save_buffer");
       }
 
       memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
       png_free(png_ptr, old_buffer);
+      old_buffer = NULL;
       png_ptr->save_buffer_max = new_max;
    }
    if (png_ptr->current_buffer_size)
@@ -725,18 +617,13 @@ png_push_restore_buffer(png_structrp png_ptr, png_bytep buffer,
 void /* PRIVATE */
 png_push_read_IDAT(png_structrp png_ptr)
 {
-   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+   if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
    {
       png_byte chunk_length[4];
       png_byte chunk_tag[4];
 
       /* TODO: this code can be commoned up with the same code in push_read */
-      if (png_ptr->buffer_size < 8)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_LT(8)
       png_push_fill_buffer(png_ptr, chunk_length, 4);
       png_ptr->push_length = png_get_uint_31(png_ptr, chunk_length);
       png_reset_crc(png_ptr);
@@ -748,7 +635,7 @@ png_push_read_IDAT(png_structrp png_ptr)
       {
          png_ptr->process_mode = PNG_READ_CHUNK_MODE;
 
-         if (!(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+         if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
             png_error(png_ptr, "Not enough compressed data");
 
          return;
@@ -757,7 +644,7 @@ png_push_read_IDAT(png_structrp png_ptr)
       png_ptr->idat_size = png_ptr->push_length;
    }
 
-   if (png_ptr->idat_size && png_ptr->save_buffer_size)
+   if (png_ptr->idat_size != 0 && png_ptr->save_buffer_size != 0)
    {
       png_size_t save_size = png_ptr->save_buffer_size;
       png_uint_32 idat_size = png_ptr->idat_size;
@@ -784,7 +671,7 @@ png_push_read_IDAT(png_structrp png_ptr)
       png_ptr->save_buffer_ptr += save_size;
    }
 
-   if (png_ptr->idat_size && png_ptr->current_buffer_size)
+   if (png_ptr->idat_size != 0 && png_ptr->current_buffer_size != 0)
    {
       png_size_t save_size = png_ptr->current_buffer_size;
       png_uint_32 idat_size = png_ptr->idat_size;
@@ -809,14 +696,9 @@ png_push_read_IDAT(png_structrp png_ptr)
       png_ptr->current_buffer_size -= save_size;
       png_ptr->current_buffer_ptr += save_size;
    }
-   if (!png_ptr->idat_size)
+   if (png_ptr->idat_size == 0)
    {
-      if (png_ptr->buffer_size < 4)
-      {
-         png_push_save_buffer(png_ptr);
-         return;
-      }
-
+      PNG_PUSH_SAVE_BUFFER_IF_LT(4)
       png_crc_finish(png_ptr, 0);
       png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
       png_ptr->mode |= PNG_AFTER_IDAT;
@@ -844,7 +726,7 @@ png_process_IDAT_data(png_structrp png_ptr, png_bytep buffer,
     * or the stream marked as finished.
     */
    while (png_ptr->zstream.avail_in > 0 &&
-      !(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+      (png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
    {
       int ret;
 
@@ -961,7 +843,7 @@ png_push_process_row(png_structrp png_ptr)
    memcpy(png_ptr->prev_row, png_ptr->row_buf, row_info.rowbytes + 1);
 
 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
-   if (png_ptr->transformations)
+   if (png_ptr->transformations != 0)
       png_do_read_transformations(png_ptr, &row_info);
 #endif
 
@@ -978,15 +860,16 @@ png_push_process_row(png_structrp png_ptr)
 
 
 #ifdef PNG_READ_INTERLACING_SUPPORTED
-   /* Blow up interlaced rows to full size */
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   /* Expand interlaced rows to full size */
+   if (png_ptr->interlaced != 0 &&
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
    {
       if (png_ptr->pass < 6)
          png_do_read_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass,
             png_ptr->transformations);
 
-    switch (png_ptr->pass)
-    {
+      switch (png_ptr->pass)
+      {
          case 0:
          {
             int i;
@@ -1189,7 +1072,7 @@ png_read_push_finish_row(png_structrp png_ptr)
       return;
 
 #ifdef PNG_READ_INTERLACING_SUPPORTED
-   if (png_ptr->interlaced)
+   if (png_ptr->interlaced != 0)
    {
       png_ptr->row_number = 0;
       memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
@@ -1213,7 +1096,7 @@ png_read_push_finish_row(png_structrp png_ptr)
              png_pass_start[png_ptr->pass]) /
              png_pass_inc[png_ptr->pass];
 
-         if (png_ptr->transformations & PNG_INTERLACE)
+         if ((png_ptr->transformations & PNG_INTERLACE) != 0)
             break;
 
          png_ptr->num_rows = (png_ptr->height +
@@ -1223,7 +1106,7 @@ png_read_push_finish_row(png_structrp png_ptr)
 
       } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
    }
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 }
 
 void /* PRIVATE */
@@ -1261,9 +1144,9 @@ png_progressive_combine_row(png_const_structrp png_ptr, png_bytep old_row,
     * it must be png_ptr->row_buf+1
     */
    if (new_row != NULL)
-      png_combine_row(png_ptr, old_row, 1/*display*/);
+      png_combine_row(png_ptr, old_row, 1/*blocky display*/);
 }
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 
 void PNGAPI
 png_set_progressive_read_fn(png_structrp png_ptr, png_voidp progressive_ptr,
@@ -1288,4 +1171,4 @@ png_get_progressive_ptr(png_const_structrp png_ptr)
 
    return png_ptr->io_ptr;
 }
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+#endif /* PROGRESSIVE_READ */

pngpriv.h

@@ -2,7 +2,7 @@
 /* pngpriv.h - private declarations for use inside libpng
  *
  * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -125,6 +125,94 @@
 
 #endif /* VERSION_INFO_ONLY */
 
+/* Compile time options.
+ * =====================
+ * In a multi-arch build the compiler may compile the code several times for the
+ * same object module, producing different binaries for different architectures.
+ * When this happens configure-time setting of the target host options cannot be
+ * done and this interferes with the handling of the ARM NEON optimizations, and
+ * possibly other similar optimizations.  Put additional tests here; in general
+ * this is needed when the same option can be changed at both compile time and
+ * run time depending on the target OS (i.e. iOS vs Android.)
+ *
+ * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
+ * this is not possible with certain compilers (Oracle SUN OS CC), as a result
+ * it is necessary to ensure that all extern functions that *might* be used
+ * regardless of $(CFLAGS) get declared in this file.  The test on __ARM_NEON__
+ * below is one example of this behavior because it is controlled by the
+ * presence or not of -mfpu=neon on the GCC command line, it is possible to do
+ * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
+ * do this.
+ */
+#ifndef PNG_ARM_NEON_OPT
+   /* ARM NEON optimizations are being controlled by the compiler settings,
+    * typically the target FPU.  If the FPU has been set to NEON (-mfpu=neon
+    * with GCC) then the compiler will define __ARM_NEON__ and we can rely
+    * unconditionally on NEON instructions not crashing, otherwise we must
+    * disable use of NEON instructions.
+    *
+    * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
+    * can only be turned on automatically if that is supported too.  If
+    * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
+    * to compile with an appropriate #error if ALIGNED_MEMORY has been turned
+    * off.
+    */
+#  if defined(__ARM_NEON__) && defined(PNG_ALIGNED_MEMORY_SUPPORTED)
+#     define PNG_ARM_NEON_OPT 2
+#  else
+#     define PNG_ARM_NEON_OPT 0
+#  endif
+#endif
+
+#if PNG_ARM_NEON_OPT > 0
+   /* NEON optimizations are to be at least considered by libpng, so enable the
+    * callbacks to do this.
+    */
+#  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
+
+   /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used
+    * if possible - if __ARM_NEON__ is set and the compiler version is not known
+    * to be broken.  This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can
+    * be:
+    *
+    *    1  The intrinsics code (the default with __ARM_NEON__)
+    *    2  The hand coded assembler (the default without __ARM_NEON__)
+    *
+    * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however
+    * this is *NOT* supported and may cease to work even after a minor revision
+    * to libpng.  It *is* valid to do this for testing purposes, e.g. speed
+    * testing or a new compiler, but the results should be communicated to the
+    * libpng implementation list for incorporation in the next minor release.
+    */
+#  ifndef PNG_ARM_NEON_IMPLEMENTATION
+#     ifdef __ARM_NEON__
+#        if defined(__clang__)
+            /* At present it is unknown by the libpng developers which versions
+             * of clang support the intrinsics, however some or perhaps all
+             * versions do not work with the assembler so this may be
+             * irrelevant, so just use the default (do nothing here.)
+             */
+#        elif defined(__GNUC__)
+            /* GCC 4.5.4 NEON support is known to be broken.  4.6.3 is known to
+             * work, so if this *is* GCC, or G++, look for a version >4.5
+             */
+#           if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)
+#              define PNG_ARM_NEON_IMPLEMENTATION 2
+#           endif /* no GNUC support */
+#        endif /* __GNUC__ */
+#     else /* !defined __ARM_NEON__ */
+         /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
+          */
+#        define PNG_ARM_NEON_IMPLEMENTATION 2
+#     endif /* __ARM_NEON__ */
+#  endif /* !defined PNG_ARM_NEON_IMPLEMENTATION */
+
+#  ifndef PNG_ARM_NEON_IMPLEMENTATION
+      /* Use the intrinsics code by default. */
+#     define PNG_ARM_NEON_IMPLEMENTATION 1
+#  endif
+#endif /* PNG_ARM_NEON_OPT > 0 */
+
 /* Is this a build of a DLL where compilation of the object modules requires
  * different preprocessor settings to those required for a simple library?  If
  * so PNG_BUILD_DLL must be set.
@@ -203,6 +291,11 @@
       extern PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
 #endif
 
+#ifndef PNG_INTERNAL_CALLBACK
+#  define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
+      extern PNG_FUNCTION(type, (PNGCBAPI name), args, PNG_EMPTY attributes)
+#endif
+
 /* If floating or fixed point APIs are disabled they may still be compiled
  * internally.  To handle this make sure they are declared as the appropriate
  * internal extern function (otherwise the symbol prefixing stuff won't work and
@@ -336,8 +429,6 @@
 #ifdef PNG_WARNINGS_SUPPORTED
 #  define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
 #else
-#  define png_warning(s1,s2) ((void)(s1))
-#  define png_chunk_warning(s1,s2) ((void)(s1))
 #  define png_warning_parameter(p,number,string) ((void)0)
 #  define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
 #  define png_warning_parameter_signed(p,number,format,value) ((void)0)
@@ -345,8 +436,6 @@
 #  define PNG_WARNING_PARAMETERS(p)
 #endif
 #ifndef PNG_ERROR_TEXT_SUPPORTED
-#  define png_error(s1,s2) png_err(s1)
-#  define png_chunk_error(s1,s2) png_err(s1)
 #  define png_fixed_error(s1,s2) png_err(s1)
 #endif
 
@@ -616,71 +705,6 @@
  */
 #endif
 
-/* Constants for known chunk types.  If you need to add a chunk, define the name
- * here.  For historical reasons these constants have the form png_<name>; i.e.
- * the prefix is lower case.  Please use decimal values as the parameters to
- * match the ISO PNG specification and to avoid relying on the C locale
- * interpretation of character values.
- *
- * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
- * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
- * to be generated if required.
- *
- * PNG_32b correctly produces a value shifted by up to 24 bits, even on
- * architectures where (int) is only 16 bits.
- */
-#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
-#define PNG_CHUNK(b1,b2,b3,b4) \
-   (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
-
-#define png_IHDR PNG_CHUNK( 73,  72,  68,  82)
-#define png_IDAT PNG_CHUNK( 73,  68,  65,  84)
-#define png_IEND PNG_CHUNK( 73,  69,  78,  68)
-#define png_PLTE PNG_CHUNK( 80,  76,  84,  69)
-#define png_bKGD PNG_CHUNK( 98,  75,  71,  68)
-#define png_cHRM PNG_CHUNK( 99,  72,  82,  77)
-#define png_gAMA PNG_CHUNK(103,  65,  77,  65)
-#define png_hIST PNG_CHUNK(104,  73,  83,  84)
-#define png_iCCP PNG_CHUNK(105,  67,  67,  80)
-#define png_iTXt PNG_CHUNK(105,  84,  88, 116)
-#define png_oFFs PNG_CHUNK(111,  70,  70, 115)
-#define png_pCAL PNG_CHUNK(112,  67,  65,  76)
-#define png_sCAL PNG_CHUNK(115,  67,  65,  76)
-#define png_pHYs PNG_CHUNK(112,  72,  89, 115)
-#define png_sBIT PNG_CHUNK(115,  66,  73,  84)
-#define png_sPLT PNG_CHUNK(115,  80,  76,  84)
-#define png_sRGB PNG_CHUNK(115,  82,  71,  66)
-#define png_sTER PNG_CHUNK(115,  84,  69,  82)
-#define png_tEXt PNG_CHUNK(116,  69,  88, 116)
-#define png_tIME PNG_CHUNK(116,  73,  77,  69)
-#define png_tRNS PNG_CHUNK(116,  82,  78,  83)
-#define png_zTXt PNG_CHUNK(122,  84,  88, 116)
-
-/* The following will work on (signed char*) strings, whereas the get_uint_32
- * macro will fail on top-bit-set values because of the sign extension.
- */
-#define PNG_CHUNK_FROM_STRING(s)\
-   PNG_CHUNK(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
-
-/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
- * signed and the argument is a (char[])  This macro will fail miserably on
- * systems where (char) is more than 8 bits.
- */
-#define PNG_STRING_FROM_CHUNK(s,c)\
-   (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
-   ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
-
-/* Do the same but terminate with a null character. */
-#define PNG_CSTRING_FROM_CHUNK(s,c)\
-   (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
-
-/* Test on flag values as defined in the spec (section 5.4): */
-#define PNG_CHUNK_ANCILLIARY(c)   (1 & ((c) >> 29))
-#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLIARY(c))
-#define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
-#define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
-#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
-
 /* Gamma values (new at libpng-1.5.4): */
 #define PNG_GAMMA_MAC_OLD 151724  /* Assume '1.8' is really 2.2/1.45! */
 #define PNG_GAMMA_MAC_INVERSE 65909
@@ -694,6 +718,24 @@
 #include "pngstruct.h"
 #include "pnginfo.h"
 
+/* Validate the include paths - the include path used to generate pnglibconf.h
+ * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
+ */
+#if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
+#  error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
+      "-I (include path) error: see the notes in pngpriv.h"
+   /* This means that when pnglibconf.h was built the copy of zlib.h that it
+    * used is not the same as the one being used here.  Because the build of
+    * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
+    * zlib version number and because this affects handling of certain broken
+    * PNG files the -I directives must match.
+    *
+    * The most likely explanation is that you passed a -I in CFLAGS, this will
+    * not work; all the preprocessor directories and in particular all the -I
+    * directives must be in CPPFLAGS.
+    */
+#endif
+
 /* This is used for 16 bit gamma tables -- only the top level pointers are
  * const; this could be changed:
  */
@@ -956,7 +998,7 @@ PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
 
 #ifdef PNG_WRITE_zTXt_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
-    key, png_const_charp text, png_size_t text_len, int compression),PNG_EMPTY);
+    key, png_const_charp text, int compression),PNG_EMPTY);
 #endif
 
 #ifdef PNG_WRITE_iTXt_SUPPORTED
@@ -1095,7 +1137,7 @@ PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
    PNG_EMPTY);
    /* Finish a row while reading, dealing with interlacing passes, etc. */
-#endif
+#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
 
 /* Initialize the row buffers, etc. */
 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
@@ -1106,32 +1148,7 @@ PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
     png_inforp info_ptr),PNG_EMPTY);
 #endif
 
-/* These are the functions that do the transformations */
-#ifdef PNG_READ_FILLER_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_filler,(png_row_infop row_info,
-    png_bytep row, png_uint_32 filler, png_uint_32 flags),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_swap_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_write_swap_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_invert_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_write_invert_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
+/* Shared transform functions, defined in pngtran.c */
 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
     defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
 PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
@@ -1151,96 +1168,16 @@ PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
     png_bytep row),PNG_EMPTY);
 #endif
 
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-PNG_INTERNAL_FUNCTION(int,png_do_rgb_to_gray,(png_structrp png_ptr,
-    png_row_infop row_info, png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_gray_to_rgb,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_PACK_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_unpack,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_unshift,(png_row_infop row_info,
-    png_bytep row, png_const_color_8p sig_bits),PNG_EMPTY);
-#endif
-
 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
 PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
     png_bytep row),PNG_EMPTY);
 #endif
 
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_scale_16_to_8,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_chop,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_quantize,(png_row_infop row_info,
-    png_bytep row, png_const_bytep palette_lookup,
-    png_const_bytep quantize_lookup),PNG_EMPTY);
-
-#  ifdef PNG_CORRECT_PALETTE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_correct_palette,(png_structrp png_ptr,
-    png_colorp palette, int num_palette),PNG_EMPTY);
-#  endif
-#endif
-
 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
 PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
     png_bytep row),PNG_EMPTY);
 #endif
 
-#ifdef PNG_WRITE_PACK_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_pack,(png_row_infop row_info,
-   png_bytep row, png_uint_32 bit_depth),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_shift,(png_row_infop row_info,
-    png_bytep row, png_const_color_8p bit_depth),PNG_EMPTY);
-#endif
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
-    defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_compose,(png_row_infop row_info,
-    png_bytep row, png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_gamma,(png_row_infop row_info,
-    png_bytep row, png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_encode_alpha,(png_row_infop row_info,
-   png_bytep row, png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_expand_palette,(png_row_infop row_info,
-    png_bytep row, png_const_colorp palette, png_const_bytep trans,
-    int num_trans),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_do_expand,(png_row_infop row_info,
-    png_bytep row, png_const_color_16p trans_color),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_expand_16,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
 /* The following decodes the appropriate chunks, and does error correction,
  * then calls the appropriate callback for the chunk if it is valid.
  */
@@ -1341,7 +1278,6 @@ PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
 PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr,
     png_uint_32 chunk_name),PNG_EMPTY);
 
-#ifdef PNG_READ_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
     png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
    /* This is the function that gets called for unknown chunks.  The 'keep'
@@ -1350,16 +1286,14 @@ PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
     * just skips the chunk or errors out if it is critical.
     */
 
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
+    defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
     (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
    /* Exactly as the API png_handle_as_unknown() except that the argument is a
     * 32-bit chunk name, not a string.
     */
-#endif
-#endif /* PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
 
 /* Handle the transformations for reading and writing */
 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
@@ -1430,13 +1364,6 @@ PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
 
 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
 
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_intrapixel,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_do_write_intrapixel,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
 /* Added at libpng version 1.6.0 */
 #ifdef PNG_GAMMA_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
@@ -1778,7 +1705,7 @@ PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
    png_size_t size),PNG_EMPTY);
 #endif /* pCAL || sCAL */
 
-#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
+#if defined(PNG_GAMMA_SUPPORTED) ||\
     defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
 /* Added at libpng version 1.5.0 */
 /* This is a utility to provide a*times/div (rounded) and indicate
@@ -1869,11 +1796,11 @@ typedef struct png_control
  * errors that might occur.  Returns true on success, false on failure (either
  * of the function or as a result of a png_error.)
  */
-PNG_INTERNAL_FUNCTION(void,png_safe_error,(png_structp png_ptr,
+PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr,
    png_const_charp error_message),PNG_NORETURN);
 
 #ifdef PNG_WARNINGS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_safe_warning,(png_structp png_ptr,
+PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr,
    png_const_charp warning_message),PNG_EMPTY);
 #else
 #  define png_safe_warning 0/*dummy argument*/
@@ -1895,14 +1822,22 @@ PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
 
 #endif /* SIMPLIFIED READ/WRITE */
 
+/* These are initialization functions for hardware specific PNG filter
+ * optimizations; list these here then select the appropriate one at compile
+ * time using the macro PNG_FILTER_OPTIMIZATIONS.  If the macro is not defined
+ * the generic code is used.
+ */
 #ifdef PNG_FILTER_OPTIMIZATIONS
 PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structrp png_ptr,
-    unsigned int bpp), PNG_EMPTY);
-   /* This is the initialization function for hardware specific optimizations,
-    * one implementation (for ARM NEON machines) is contained in
-    * arm/filter_neon.c.  It need not be defined - the generic code will be used
-    * if not.
+   unsigned int bpp), PNG_EMPTY);
+   /* Just declare the optimization that will be used */
+#else
+   /* List *all* the possible optimizations here - this branch is required if
+    * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
+    * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
     */
+PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
+   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #endif
 
 /* Maintainer: Put new private prototypes here ^ */

pngrio.c

@@ -1,8 +1,8 @@
 
 /* pngrio.c - functions for data input
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.9 [February 6, 2014]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -117,4 +117,4 @@ png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
    png_ptr->output_flush_fn = NULL;
 #endif
 }
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ */

pngrutil.c

@@ -2,7 +2,7 @@
 /* pngrutil.c - utilities to read a PNG file
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -18,17 +18,6 @@
 
 #ifdef PNG_READ_SUPPORTED
 
-png_uint_32 PNGAPI
-png_get_uint_31(png_const_structrp png_ptr, png_const_bytep buf)
-{
-   png_uint_32 uval = png_get_uint_32(buf);
-
-   if (uval > PNG_UINT_31_MAX)
-      png_error(png_ptr, "PNG unsigned integer out of range");
-
-   return (uval);
-}
-
 #if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_READ_cHRM_SUPPORTED)
 /* The following is a variation on the above for use with the fixed
  * point values used for gAMA and cHRM.  Instead of png_error it
@@ -51,7 +40,7 @@ png_get_fixed_point(png_structrp png_ptr, png_const_bytep buf)
 
    return PNG_FIXED_ERROR;
 }
-#endif
+#endif /* READ_gAMA or READ_cHRM */
 
 #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
 /* NOTE: the read macros will obscure these definitions, so that if
@@ -67,13 +56,7 @@ png_get_fixed_point(png_structrp png_ptr, png_const_bytep buf)
 png_uint_32 (PNGAPI
 png_get_uint_32)(png_const_bytep buf)
 {
-   png_uint_32 uval =
-       ((png_uint_32)(*(buf    )) << 24) +
-       ((png_uint_32)(*(buf + 1)) << 16) +
-       ((png_uint_32)(*(buf + 2)) <<  8) +
-       ((png_uint_32)(*(buf + 3))      ) ;
-
-   return uval;
+   return PNG_U32(buf[0], buf[1], buf[2], buf[3]);
 }
 
 /* Grab a signed 32-bit integer from a buffer in big-endian format.  The
@@ -84,31 +67,31 @@ png_get_uint_32)(png_const_bytep buf)
 png_int_32 (PNGAPI
 png_get_int_32)(png_const_bytep buf)
 {
-   png_uint_32 uval = png_get_uint_32(buf);
-   if ((uval & 0x80000000) == 0) /* non-negative */
-      return uval;
-
-   uval = (uval ^ 0xffffffff) + 1;  /* 2's complement: -x = ~x+1 */
-   return -(png_int_32)uval;
+   return PNG_S32(buf[0], buf[1], buf[2], buf[3]);
 }
 
 /* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
 png_uint_16 (PNGAPI
 png_get_uint_16)(png_const_bytep buf)
 {
-   /* ANSI-C requires an int value to accomodate at least 16 bits so this
-    * works and allows the compiler not to worry about possible narrowing
-    * on 32 bit systems.  (Pre-ANSI systems did not make integers smaller
-    * than 16 bits either.)
-    */
-   unsigned int val =
-       ((unsigned int)(*buf) << 8) +
-       ((unsigned int)(*(buf + 1)));
-
-   return (png_uint_16)val;
+   return PNG_U16(buf[0], buf[1]);
 }
+#endif /* READ_INT_FUNCTIONS */
 
-#endif /* PNG_READ_INT_FUNCTIONS_SUPPORTED */
+/* This is an exported function however its error handling is too harsh for most
+ * internal use.  For example if it were used for reading the chunk parameters
+ * it would error out even on ancillary chunks that can be ignored.
+ */
+png_uint_32 PNGAPI
+png_get_uint_31(png_const_structrp png_ptr, png_const_bytep buf)
+{
+   png_uint_32 uval = png_get_uint_32(buf);
+
+   if (uval > PNG_UINT_31_MAX)
+      png_error(png_ptr, "PNG unsigned integer out of range");
+
+   return uval;
+}
 
 /* Read and check the PNG file signature */
 void /* PRIVATE */
@@ -219,18 +202,15 @@ png_crc_finish(png_structrp png_ptr, png_uint_32 skip)
 
    if (png_crc_error(png_ptr))
    {
-      if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name) ?
-          !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) :
-          (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE))
+      if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name) ?
+          (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN) == 0:
+          (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE) != 0)
       {
          png_chunk_warning(png_ptr, "CRC error");
       }
 
       else
-      {
-         png_chunk_benign_error(png_ptr, "CRC error");
-         return (0);
-      }
+         png_chunk_error(png_ptr, "CRC error");
 
       return (1);
    }
@@ -248,7 +228,7 @@ png_crc_error(png_structrp png_ptr)
    png_uint_32 crc;
    int need_crc = 1;
 
-   if (PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name))
+   if (PNG_CHUNK_ANCILLARY(png_ptr->chunk_name))
    {
       if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
           (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
@@ -268,7 +248,7 @@ png_crc_error(png_structrp png_ptr)
    /* The chunk CRC must be serialized in a single I/O call. */
    png_read_data(png_ptr, crc_bytes, 4);
 
-   if (need_crc)
+   if (need_crc != 0)
    {
       crc = png_get_uint_32(crc_bytes);
       return ((int)(crc != png_ptr->crc));
@@ -278,6 +258,10 @@ png_crc_error(png_structrp png_ptr)
       return (0);
 }
 
+#if defined(PNG_READ_iCCP_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) ||\
+    defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_READ_sCAL_SUPPORTED) ||\
+    defined(PNG_READ_sPLT_SUPPORTED) || defined(PNG_READ_tEXt_SUPPORTED) ||\
+    defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_SEQUENTIAL_READ_SUPPORTED)
 /* Manage the read buffer; this simply reallocates the buffer if it is not small
  * enough (or if it is not allocated).  The routine returns a pointer to the
  * buffer; if an error occurs and 'warn' is set the routine returns NULL, else
@@ -310,21 +294,17 @@ png_read_buffer(png_structrp png_ptr, png_alloc_size_t new_size, int warn)
 
       else if (warn < 2) /* else silent */
       {
-#ifdef PNG_WARNINGS_SUPPORTED
-         if (warn)
+         if (warn != 0)
              png_chunk_warning(png_ptr, "insufficient memory to read chunk");
+
          else
-#endif
-         {
-#ifdef PNG_ERROR_TEXT_SUPPORTED
              png_chunk_error(png_ptr, "insufficient memory to read chunk");
-#endif
-         }
       }
    }
 
    return buffer;
 }
+#endif /* READ_iCCP|iTXt|pCAL|sCAL|sPLT|tEXt|zTXt|SEQUENTIAL_READ */
 
 /* png_inflate_claim: claim the zstream for some nefarious purpose that involves
  * decompression.  Returns Z_OK on success, else a zlib error code.  It checks
@@ -332,7 +312,7 @@ png_read_buffer(png_structrp png_ptr, png_alloc_size_t new_size, int warn)
  * chunk apparently owns the stream.  Prior to release it does a png_error.
  */
 static int
-png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
+png_inflate_claim(png_structrp png_ptr, png_uint_32 owner)
 {
    if (png_ptr->zowner != 0)
    {
@@ -367,6 +347,22 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
     */
    {
       int ret; /* zlib return code */
+#     if PNG_ZLIB_VERNUM >= 0x1240
+
+#        if defined(PNG_SET_OPTION_SUPPORTED) && \
+            defined(PNG_MAXIMUM_INFLATE_WINDOW)
+            int window_bits;
+
+            if (((png_ptr->options >> PNG_MAXIMUM_INFLATE_WINDOW) & 3) ==
+               PNG_OPTION_ON)
+               window_bits = 15;
+
+            else
+               window_bits = 0;
+#        else
+#           define window_bits 0
+#        endif
+#     endif
 
       /* Set this for safety, just in case the previous owner left pointers to
        * memory allocations.
@@ -378,8 +374,7 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
 
       if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
       {
-#        if ZLIB_VERNUM < 0x1240
-            PNG_UNUSED(window_bits)
+#        if PNG_ZLIB_VERNUM < 0x1240
             ret = inflateReset(&png_ptr->zstream);
 #        else
             ret = inflateReset2(&png_ptr->zstream, window_bits);
@@ -388,7 +383,7 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
 
       else
       {
-#        if ZLIB_VERNUM < 0x1240
+#        if PNG_ZLIB_VERNUM < 0x1240
             ret = inflateInit(&png_ptr->zstream);
 #        else
             ret = inflateInit2(&png_ptr->zstream, window_bits);
@@ -406,6 +401,10 @@ png_inflate_claim(png_structrp png_ptr, png_uint_32 owner, int window_bits)
 
       return ret;
    }
+
+#  ifdef window_bits
+#     undef window_bits
+#  endif
 }
 
 #ifdef PNG_READ_COMPRESSED_TEXT_SUPPORTED
@@ -502,7 +501,7 @@ png_inflate(png_structrp png_ptr, png_uint_32 owner, int finish,
           * end of the output buffer.
           */
          ret = inflate(&png_ptr->zstream, avail_out > 0 ? Z_NO_FLUSH :
-            (finish ? Z_FINISH : Z_SYNC_FLUSH));
+             (finish ? Z_FINISH : Z_SYNC_FLUSH));
       } while (ret == Z_OK);
 
       /* For safety kill the local buffer pointer now */
@@ -578,14 +577,8 @@ png_decompress_chunk(png_structrp png_ptr,
       if (limit < *newlength)
          *newlength = limit;
 
-      /* Now try to claim the stream; the 'warn' setting causes zlib to be told
-       * to use the maximum window size during inflate; this hides errors in the
-       * deflate header window bits value which is used if '0' is passed.  In
-       * fact this only has an effect with zlib versions 1.2.4 and later - see
-       * the comments in png_inflate_claim above.
-       */
-      ret = png_inflate_claim(png_ptr, png_ptr->chunk_name,
-         png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN ? 15 : 0);
+      /* Now try to claim the stream. */
+      ret = png_inflate_claim(png_ptr, png_ptr->chunk_name);
 
       if (ret == Z_OK)
       {
@@ -627,7 +620,7 @@ png_decompress_chunk(png_structrp png_ptr,
                   {
                      if (new_size == *newlength)
                      {
-                        if (terminate)
+                        if (terminate != 0)
                            text[prefix_size + *newlength] = 0;
 
                         if (prefix_size > 0)
@@ -708,7 +701,7 @@ png_decompress_chunk(png_structrp png_ptr,
       return Z_MEM_ERROR;
    }
 }
-#endif /* PNG_READ_COMPRESSED_TEXT_SUPPORTED */
+#endif /* READ_COMPRESSED_TEXT */
 
 #ifdef PNG_READ_iCCP_SUPPORTED
 /* Perform a partial read and decompress, producing 'avail_out' bytes and
@@ -968,15 +961,10 @@ png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))
       {
          if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)
-         {
-            png_chunk_benign_error(png_ptr, "CRC error");
-         }
+            return;
 
          else
-         {
-            png_chunk_warning(png_ptr, "CRC error");
-            return;
-         }
+            png_chunk_error(png_ptr, "CRC error");
       }
 
       /* Otherwise, we (optionally) emit a warning and use the chunk. */
@@ -1008,7 +996,7 @@ png_handle_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
     */
 #ifdef PNG_READ_tRNS_SUPPORTED
    if (png_ptr->num_trans > 0 ||
-      (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS) != 0))
+       (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS) != 0))
    {
       /* Cancel this because otherwise it would be used if the transforms
        * require it.  Don't cancel the 'valid' flag because this would prevent
@@ -1094,13 +1082,12 @@ png_handle_gAMA(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 void /* PRIVATE */
 png_handle_sBIT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 {
-   unsigned int truelen;
+   unsigned int truelen, i;
+   png_byte sample_depth;
    png_byte buf[4];
 
    png_debug(1, "in png_handle_sBIT");
 
-   buf[0] = buf[1] = buf[2] = buf[3] = 0;
-
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_chunk_error(png_ptr, "missing IHDR");
 
@@ -1119,10 +1106,16 @@ png_handle_sBIT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
    }
 
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   {
       truelen = 3;
+      sample_depth = 8;
+   }
 
    else
+   {
       truelen = png_ptr->channels;
+      sample_depth = png_ptr->bit_depth;
+   }
 
    if (length != truelen || length > 4)
    {
@@ -1131,11 +1124,19 @@ png_handle_sBIT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       return;
    }
 
+   buf[0] = buf[1] = buf[2] = buf[3] = sample_depth;
    png_crc_read(png_ptr, buf, truelen);
 
    if (png_crc_finish(png_ptr, 0))
       return;
 
+   for (i=0; i<truelen; ++i)
+      if (buf[i] == 0 || buf[i] > sample_depth)
+      {
+         png_chunk_benign_error(png_ptr, "invalid");
+         return;
+      }
+
    if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
    {
       png_ptr->sig_bit.red = buf[0];
@@ -1277,7 +1278,7 @@ png_handle_sRGB(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
    (void)png_colorspace_set_sRGB(png_ptr, &png_ptr->colorspace, intent);
    png_colorspace_sync(png_ptr, info_ptr);
 }
-#endif /* PNG_READ_sRGB_SUPPORTED */
+#endif /* READ_sRGB */
 
 #ifdef PNG_READ_iCCP_SUPPORTED
 void /* PRIVATE */
@@ -1303,9 +1304,9 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
     * chunk is just ignored, so does not invalidate the color space.  An
     * alternative is to set the 'invalid' flags at the start of this routine
     * and only clear them in they were not set before and all the tests pass.
-    * The minimum 'deflate' stream is assumed to be just the 2 byte header and 4
-    * byte checksum.  The keyword must be one character and there is a
-    * terminator (0) byte and the compression method.
+    * The minimum 'deflate' stream is assumed to be just the 2 byte header and
+    * 4 byte checksum.  The keyword must be at least one character and there is
+    * a terminator (0) byte and the compression method.
     */
    if (length < 9)
    {
@@ -1355,8 +1356,7 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
          {
             read_length -= keyword_length+2;
 
-            if (png_inflate_claim(png_ptr, png_iCCP,
-               png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN ? 15 : 0) == Z_OK)
+            if (png_inflate_claim(png_ptr, png_iCCP) == Z_OK)
             {
                Byte profile_header[132];
                Byte local_buffer[PNG_INFLATE_BUF_SIZE];
@@ -1406,7 +1406,7 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
                               (sizeof local_buffer), &length,
                               profile + (sizeof profile_header), &size, 0);
 
-                           /* Still expect a a buffer error because we expect
+                           /* Still expect a buffer error because we expect
                             * there to be some tag data!
                             */
                            if (size == 0)
@@ -1543,7 +1543,7 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       errmsg = "too many profiles";
 
    /* Failure: the reason is in 'errmsg' */
-   if (!finished)
+   if (finished == 0)
       png_crc_finish(png_ptr, length);
 
    png_ptr->colorspace.flags |= PNG_COLORSPACE_INVALID;
@@ -1551,7 +1551,7 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
    if (errmsg != NULL) /* else already output */
       png_chunk_benign_error(png_ptr, errmsg);
 }
-#endif /* PNG_READ_iCCP_SUPPORTED */
+#endif /* READ_iCCP */
 
 #ifdef PNG_READ_sPLT_SUPPORTED
 void /* PRIVATE */
@@ -1581,7 +1581,7 @@ png_handle_sPLT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          /* Warn the first time */
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          png_crc_finish(png_ptr, length);
          return;
       }
@@ -1729,7 +1729,7 @@ png_handle_sPLT(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 
    png_free(png_ptr, new_palette.entries);
 }
-#endif /* PNG_READ_sPLT_SUPPORTED */
+#endif /* READ_sPLT */
 
 #ifdef PNG_READ_tRNS_SUPPORTED
 void /* PRIVATE */
@@ -2371,7 +2371,7 @@ png_handle_tEXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          return;
       }
    }
@@ -2450,7 +2450,7 @@ png_handle_zTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          return;
       }
    }
@@ -2559,7 +2559,7 @@ png_handle_iTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       if (--png_ptr->user_chunk_cache_max == 1)
       {
          png_crc_finish(png_ptr, length);
-         png_chunk_benign_error(png_ptr, "chunk cache full");
+         png_chunk_benign_error(png_ptr, "no space in chunk cache");
          return;
       }
    }
@@ -2628,7 +2628,7 @@ png_handle_iTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
       /* prefix_length should now be at the trailing '\0' of the translated
        * keyword, but it may already be over the end.  None of this arithmetic
        * can overflow because chunks are at most 2^31 bytes long, but on 16-bit
-       * systems the available allocaton may overflow.
+       * systems the available allocation may overflow.
        */
       ++prefix_length;
 
@@ -2660,7 +2660,7 @@ png_handle_iTXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 
          buffer[uncompressed_length+prefix_length] = 0;
 
-         if (compressed)
+         if (compressed == 0)
             text.compression = PNG_ITXT_COMPRESSION_NONE;
 
          else
@@ -2744,7 +2744,7 @@ png_cache_unknown_chunk(png_structrp png_ptr, png_uint_32 length)
       return 1;
    }
 }
-#endif /* PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */
+#endif /* READ_UNKNOWN_CHUNKS */
 
 /* Handle an unknown, or known but disabled, chunk */
 void /* PRIVATE */
@@ -2801,19 +2801,26 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
             if (ret < 0)
                png_chunk_error(png_ptr, "error in user chunk");
 
-            else if (ret > 0) /* chunk was handled */
+            else if (ret == 0)
+            {
+               /* Use the default handling, note that if there is per-chunk
+                * handling specified it has already been set into 'keep'.
+                *
+                * NOTE: this is an API change in 1.7.0. Prior to 1.7.0 libpng
+                * would force keep to PNG_HANDLE_CHUNK_IF_SAFE at this point,
+                * and 1.6.0 would issue a warning if this caused a default of
+                * discarding the chunk to be changed.
+                */
+               if (keep == PNG_HANDLE_CHUNK_AS_DEFAULT)
+                  keep = png_ptr->unknown_default;
+            }
+
+            else /* chunk was handled */
             {
                handled = 1;
                /* Critical chunks can be safely discarded at this point. */
                keep = PNG_HANDLE_CHUNK_NEVER;
             }
-
-            /* else: use the default handling.
-             * NOTE: this is an API change in 1.7.0, prior to 1.7.0 libpng would
-             * force keep to PNG_HANDLE_CHUNK_IF_SAFE at this point, and 1.6.0
-             * would issue a warning if this caused a default of discarding the
-             * chunk to be changed.
-             */
          }
 
          else
@@ -2836,7 +2843,7 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
 
          if (keep == PNG_HANDLE_CHUNK_ALWAYS ||
             (keep == PNG_HANDLE_CHUNK_IF_SAFE &&
-             PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name)))
+             PNG_CHUNK_ANCILLARY(png_ptr->chunk_name)))
          {
             if (!png_cache_unknown_chunk(png_ptr, length))
                keep = PNG_HANDLE_CHUNK_NEVER;
@@ -2870,14 +2877,14 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
        */
       if (keep == PNG_HANDLE_CHUNK_ALWAYS ||
          (keep == PNG_HANDLE_CHUNK_IF_SAFE &&
-          PNG_CHUNK_ANCILLIARY(png_ptr->chunk_name)))
+          PNG_CHUNK_ANCILLARY(png_ptr->chunk_name)))
       {
 #     ifdef PNG_USER_LIMITS_SUPPORTED
          switch (png_ptr->user_chunk_cache_max)
          {
             case 2:
                png_ptr->user_chunk_cache_max = 1;
-               png_chunk_benign_error(png_ptr, "chunk cache full");
+               png_chunk_benign_error(png_ptr, "no space in chunk cache");
                /* FALL THROUGH */
             case 1:
                /* NOTE: prior to 1.6.0 this case resulted in an unknown critical
@@ -2901,9 +2908,8 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
          }
 #     endif
       }
-#  else /* no store support! */
+#  else /* no store support: the chunk must be handled by the user callback */
       PNG_UNUSED(info_ptr)
-#     error untested code (reading unknown chunks with no store support)
 #  endif
 
    /* Regardless of the error handling below the cached data (if any) can be
@@ -2919,7 +2925,7 @@ png_handle_unknown(png_structrp png_ptr, png_inforp info_ptr,
    png_crc_finish(png_ptr, length);
    PNG_UNUSED(info_ptr)
    PNG_UNUSED(keep)
-#endif /* !PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */
+#endif /* !READ_UNKNOWN_CHUNKS */
 
    /* Check for unhandled critical chunks */
    if (!handled && PNG_CHUNK_CRITICAL(png_ptr->chunk_name))
@@ -3120,7 +3126,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
 #        define S_MASKS(d,s) { S_MASK(0,d,s), S_MASK(1,d,s), S_MASK(2,d,s),\
             S_MASK(3,d,s), S_MASK(4,d,s), S_MASK(5,d,s) }
 
-#        define B_MASKS(d,s) { B_MASK(1,d,s), S_MASK(3,d,s), S_MASK(5,d,s) }
+#        define B_MASKS(d,s) { B_MASK(1,d,s), B_MASK(3,d,s), B_MASK(5,d,s) }
 
 #        define DEPTH_INDEX(d) ((d)==1?0:((d)==2?1:2))
 
@@ -3156,10 +3162,10 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
           */
 #        define MASK(pass,depth,display,png)\
             ((display)?B_MASK(pass,depth,png):S_MASK(pass,depth,png))
-#endif /* !PNG_USE_COMPILE_TIME_MASKS */
+#endif /* !USE_COMPILE_TIME_MASKS */
 
          /* Use the appropriate mask to copy the required bits.  In some cases
-          * the byte mask will be 0 or 0xff, optimize these cases.  row_width is
+          * the byte mask will be 0 or 0xff; optimize these cases.  row_width is
           * the number of pixels, but the code copies bytes, so it is necessary
           * to special case the end.
           */
@@ -3231,7 +3237,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
          }
 
          /* Work out the bytes to copy. */
-         if (display)
+         if (display != 0)
          {
             /* When doing the 'block' algorithm the pixel in the pass gets
              * replicated to adjacent pixels.  This is why the even (0,2,4,6)
@@ -3298,7 +3304,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
                /* This can only be the RGB case, so each copy is exactly one
                 * pixel and it is not necessary to check for a partial copy.
                 */
-               for(;;)
+               for (;;)
                {
                   dp[0] = sp[0], dp[1] = sp[1], dp[2] = sp[2];
 
@@ -3407,7 +3413,7 @@ png_combine_row(png_const_structrp png_ptr, png_bytep dp, int display)
                      return;
                   }
                }
-#endif /* PNG_ALIGN_ code */
+#endif /* ALIGN_ code */
 
                /* The true default - use a memcpy: */
                for (;;)
@@ -3663,7 +3669,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
 
             for (i = 0; i < row_info->width; i++)
             {
-               png_byte v[8];
+               png_byte v[8]; /* SAFE; pixel_depth does not exceed 64 */
                int j;
 
                memcpy(v, sp, pixel_bytes);
@@ -3687,7 +3693,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
    PNG_UNUSED(transformations)  /* Silence compiler warning */
 #endif
 }
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 
 static void
 png_read_filter_row_sub(png_row_infop row_info, png_bytep row,
@@ -3841,7 +3847,6 @@ png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row,
       if (pb < pa) pa = pb, a = b;
       if (pc < pa) a = c;
 
-      c = b;
       a += *row;
       *row++ = (png_byte)a;
    }
@@ -3849,7 +3854,8 @@ png_read_filter_row_paeth_multibyte_pixel(png_row_infop row_info, png_bytep row,
 
 static void
 png_init_filter_functions(png_structrp pp)
-   /* This function is called once for every PNG image to set the
+   /* This function is called once for every PNG image (except for PNG images
+    * that only use PNG_FILTER_VALUE_NONE for all rows) to set the
     * implementations required to reverse the filtering of PNG rows.  Reversing
     * the filter is the first transformation performed on the row data.  It is
     * performed in place, therefore an implementation can be selected based on
@@ -3891,10 +3897,13 @@ png_read_filter_row(png_structrp pp, png_row_infop row_info, png_bytep row,
     * PNG_FILTER_OPTIMIZATIONS to a function that overrides the generic
     * implementations.  See png_init_filter_functions above.
     */
-   if (pp->read_filter[0] == NULL)
-      png_init_filter_functions(pp);
    if (filter > PNG_FILTER_VALUE_NONE && filter < PNG_FILTER_VALUE_LAST)
+   {
+      if (pp->read_filter[0] == NULL)
+         png_init_filter_functions(pp);
+
       pp->read_filter[filter-1](row_info, row, prev_row);
+   }
 }
 
 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
@@ -4092,7 +4101,7 @@ png_read_finish_row(png_structrp png_ptr)
 
    /* Offset to next interlace block in the y direction */
    static PNG_CONST png_byte png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 
    png_debug(1, "in png_read_finish_row");
    png_ptr->row_number++;
@@ -4137,12 +4146,12 @@ png_read_finish_row(png_structrp png_ptr)
       if (png_ptr->pass < 7)
          return;
    }
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 
    /* Here after at the end of the last row of the last pass. */
    png_read_finish_IDAT(png_ptr);
 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */
 
 void /* PRIVATE */
 png_read_start_row(png_structrp png_ptr)
@@ -4188,7 +4197,7 @@ png_read_start_row(png_structrp png_ptr)
    }
 
    else
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
    {
       png_ptr->num_rows = png_ptr->height;
       png_ptr->iwidth = png_ptr->width;
@@ -4433,9 +4442,9 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
     * IDAT stream has a bogus deflate header window_bits value, but this should
     * not be happening any longer!)
     */
-   if (png_inflate_claim(png_ptr, png_IDAT, 0) != Z_OK)
+   if (png_inflate_claim(png_ptr, png_IDAT) != Z_OK)
       png_error(png_ptr, png_ptr->zstream.msg);
 
    png_ptr->flags |= PNG_FLAG_ROW_INIT;
 }
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ */

pngset.c

@@ -2,7 +2,7 @@
 /* pngset.c - storage of image information into info struct
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -59,7 +59,7 @@ png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
    xy.whitey = white_y;
 
    if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
-      2/* override with app values*/))
+       2/* override with app values*/) != 0)
       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
 
    png_colorspace_sync_info(png_ptr, info_ptr);
@@ -90,7 +90,8 @@ png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
    XYZ.blue_Y = int_blue_Y;
    XYZ.blue_Z = int_blue_Z;
 
-   if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace, &XYZ, 2))
+   if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace,
+       &XYZ, 2) != 0)
       info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;
 
    png_colorspace_sync_info(png_ptr, info_ptr);
@@ -131,7 +132,7 @@ png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
 }
 #  endif /* PNG_FLOATING_POINT_SUPPORTED */
 
-#endif /* PNG_cHRM_SUPPORTED */
+#endif /* cHRM */
 
 #ifdef PNG_gAMA_SUPPORTED
 void PNGFAPI
@@ -227,27 +228,18 @@ png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
    if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       info_ptr->channels = 1;
 
-   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+   else if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
       info_ptr->channels = 3;
 
    else
       info_ptr->channels = 1;
 
-   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+   if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
       info_ptr->channels++;
 
    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
 
-   /* Check for potential overflow */
-   if (width >
-       (PNG_UINT_32_MAX >> 3)      /* 8-byte RRGGBBAA pixels */
-       - 48       /* bigrowbuf hack */
-       - 1        /* filter byte */
-       - 7*8      /* rounding of width to multiple of 8 pixels */
-       - 8)       /* extra max_pixel_depth pad */
-      info_ptr->rowbytes = 0;
-   else
-      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
+   info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
 }
 
 #ifdef PNG_oFFs_SUPPORTED
@@ -297,12 +289,14 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
 
    /* Validate params[nparams] */
    for (i=0; i<nparams; ++i)
+   {
       if (params[i] == NULL ||
-         !png_check_fp_string(params[i], strlen(params[i])))
+          !png_check_fp_string(params[i], strlen(params[i])))
          png_error(png_ptr, "Invalid format for pCAL parameter");
+   }
 
    info_ptr->pcal_purpose = png_voidcast(png_charp,
-      png_malloc_warn(png_ptr, length));
+       png_malloc_warn(png_ptr, length));
 
    if (info_ptr->pcal_purpose == NULL)
    {
@@ -537,7 +531,7 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
 #        endif
       ))
    {
-      png_chunk_report(png_ptr, "Invalid palette", PNG_CHUNK_ERROR);
+      png_error(png_ptr, "Invalid palette");
       return;
    }
 
@@ -604,7 +598,8 @@ png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent))
+   if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace,
+       srgb_intent) != 0)
    {
       /* This causes the gAMA and cHRM to be written too */
       info_ptr->colorspace.flags |=
@@ -647,7 +642,7 @@ png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
       png_colorspace_sync_info(png_ptr, info_ptr);
 
       /* Don't do any of the copying if the profile was bad, or inconsistent. */
-      if (!result)
+      if (result == 0)
          return;
 
       /* But do write the gAMA and cHRM chunks from the profile. */
@@ -671,6 +666,7 @@ png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
    if (new_iccp_profile == NULL)
    {
       png_free(png_ptr, new_iccp_name);
+      new_iccp_name = NULL;
       png_benign_error(png_ptr,
           "Insufficient memory to process iCCP profile");
       return;
@@ -696,7 +692,7 @@ png_set_text(png_structrp png_ptr, png_inforp info_ptr,
    int ret;
    ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
 
-   if (ret)
+   if (ret != 0)
       png_error(png_ptr, "Insufficient memory to store text");
 }
 
@@ -736,7 +732,7 @@ png_set_text_2(png_structrp png_ptr, png_inforp info_ptr,
          else
             max_text = INT_MAX;
 
-         /* Now allocate a new array and copy the old members in, this does all
+         /* Now allocate a new array and copy the old members in; this does all
           * the overflow checks.
           */
          new_text = png_voidcast(png_textp,png_realloc_array(png_ptr,
@@ -866,7 +862,7 @@ png_set_text_2(png_structrp png_ptr, png_inforp info_ptr,
          textp->text = textp->key + key_len + 1;
       }
 
-      if (text_length)
+      if (text_length != 0)
          memcpy(textp->text, text_ptr[i].text, text_length);
 
       *(textp->text + text_length) = '\0';
@@ -901,7 +897,7 @@ png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
    png_debug1(1, "in %s storage function", "tIME");
 
    if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
-       (png_ptr->mode & PNG_WROTE_tIME))
+       (png_ptr->mode & PNG_WROTE_tIME) != 0)
       return;
 
    if (mod_time->month == 0   || mod_time->month > 12  ||
@@ -1070,8 +1066,8 @@ png_set_sPLT(png_structrp png_ptr,
 
       np->depth = entries->depth;
 
-      /* In the even of out-of-memory just return - there's no point keeping on
-       * trying to add sPLT chunks.
+      /* In the event of out-of-memory just return - there's no point keeping
+       * on trying to add sPLT chunks.
        */
       length = strlen(entries->name) + 1;
       np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length));
@@ -1082,8 +1078,8 @@ png_set_sPLT(png_structrp png_ptr,
       memcpy(np->name, entries->name, length);
 
       /* IMPORTANT: we have memory now that won't get freed if something else
-       * goes wrong, this code must free it.  png_malloc_array produces no
-       * warnings, use a png_chunk_report (below) if there is an error.
+       * goes wrong; this code must free it.  png_malloc_array produces no
+       * warnings; use a png_chunk_report (below) if there is an error.
        */
       np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr,
           entries->nentries, sizeof (png_sPLT_entry)));
@@ -1091,6 +1087,7 @@ png_set_sPLT(png_structrp png_ptr,
       if (np->entries == NULL)
       {
          png_free(png_ptr, np->name);
+         np->name = NULL;
          break;
       }
 
@@ -1113,7 +1110,7 @@ png_set_sPLT(png_structrp png_ptr,
    if (nentries > 0)
       png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
 }
-#endif /* PNG_sPLT_SUPPORTED */
+#endif /* sPLT */
 
 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static png_byte
@@ -1122,10 +1119,10 @@ check_location(png_const_structrp png_ptr, int location)
    location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT);
 
    /* New in 1.6.0; copy the location and check it.  This is an API
-    * change, previously the app had to use the
+    * change; previously the app had to use the
     * png_set_unknown_chunk_location API below for each chunk.
     */
-   if (location == 0 && !(png_ptr->mode & PNG_IS_READ_STRUCT))
+   if (location == 0 && (png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
    {
       /* Write struct, so unknown chunks come from the app */
       png_app_warning(png_ptr,
@@ -1171,7 +1168,7 @@ png_set_unknown_chunks(png_structrp png_ptr,
     */
 #  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
       defined(PNG_READ_SUPPORTED)
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
       {
          png_app_error(png_ptr, "no unknown chunk support on read");
          return;
@@ -1179,7 +1176,7 @@ png_set_unknown_chunks(png_structrp png_ptr,
 #  endif
 #  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
       defined(PNG_WRITE_SUPPORTED)
-      if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
       {
          png_app_error(png_ptr, "no unknown chunk support on write");
          return;
@@ -1256,8 +1253,6 @@ png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
 {
    /* This API is pretty pointless in 1.6.0 because the location can be set
     * before the call to png_set_unknown_chunks.
-    *
-    * TODO: add a png_app_warning in 1.7
     */
    if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 &&
       chunk < info_ptr->unknown_chunks_num)
@@ -1266,7 +1261,7 @@ png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
       {
          png_app_error(png_ptr, "invalid unknown chunk location");
          /* Fake out the pre 1.6.0 behavior: */
-         if ((location & PNG_HAVE_IDAT)) /* undocumented! */
+         if ((location & PNG_HAVE_IDAT) != 0) /* undocumented! */
             location = PNG_AFTER_IDAT;
 
          else
@@ -1276,6 +1271,10 @@ png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
       info_ptr->unknown_chunks[chunk].location =
          check_location(png_ptr, location);
    }
+
+   /* TODO: make this an error in 1.8 (or maybe it will become one in 1.7!) */
+   else if (png_ptr != NULL)
+      png_app_warning(png_ptr, "unknown chunk index out of range");
 }
 #endif
 
@@ -1304,10 +1303,13 @@ add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
    /* Utility function: update the 'keep' state of a chunk if it is already in
     * the list, otherwise add it to the list.
     */
-   for (i=0; i<count; ++i, list += 5) if (memcmp(list, add, 4) == 0)
+   for (i=0; i<count; ++i, list += 5)
    {
-      list[4] = (png_byte)keep;
-      return count;
+      if (memcmp(list, add, 4) == 0)
+      {
+         list[4] = (png_byte)keep;
+         return count;
+      }
    }
 
    if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
@@ -1371,7 +1373,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
       };
 
       chunk_list = chunks_to_ignore;
-      num_chunks = (sizeof chunks_to_ignore)/5;
+      num_chunks = (unsigned int)/*SAFE*/(sizeof chunks_to_ignore)/5U;
    }
 
    else /* num_chunks_in > 0 */
@@ -1404,7 +1406,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
     * required because add_one_chunk above doesn't extend the list if the 'keep'
     * parameter is the default.
     */
-   if (keep)
+   if (keep != 0)
    {
       new_list = png_voidcast(png_bytep, png_malloc(png_ptr,
           5 * (num_chunks + old_num_chunks)));
@@ -1431,12 +1433,15 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
       unsigned int i;
 
       for (i=0; i<num_chunks; ++i)
+      {
          old_num_chunks = add_one_chunk(new_list, old_num_chunks,
             chunk_list+5*i, keep);
+      }
 
       /* Now remove any spurious 'default' entries. */
       num_chunks = 0;
       for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
+      {
          if (inlist[4])
          {
             if (outlist != inlist)
@@ -1444,6 +1449,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
             outlist += 5;
             ++num_chunks;
          }
+      }
 
       /* This means the application has removed all the specialized handling. */
       if (num_chunks == 0)
@@ -1495,12 +1501,13 @@ png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+   if (info_ptr->row_pointers != NULL &&
+       (info_ptr->row_pointers != row_pointers))
       png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
 
    info_ptr->row_pointers = row_pointers;
 
-   if (row_pointers)
+   if (row_pointers != NULL)
       info_ptr->valid |= PNG_INFO_IDAT;
 }
 #endif
@@ -1515,7 +1522,7 @@ png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
        png_error(png_ptr, "invalid compression buffer size");
 
 #  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
       {
          png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
          return;
@@ -1523,7 +1530,7 @@ png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
 #  endif
 
 #  ifdef PNG_WRITE_SUPPORTED
-      if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
       {
          if (png_ptr->zowner != 0)
          {
@@ -1561,7 +1568,7 @@ png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
 void PNGAPI
 png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
 {
-   if (png_ptr && info_ptr)
+   if (png_ptr != NULL && info_ptr != NULL)
       info_ptr->valid &= ~mask;
 }
 
@@ -1599,7 +1606,7 @@ png_set_chunk_malloc_max (png_structrp png_ptr,
    if (png_ptr != NULL)
       png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
 }
-#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+#endif /* ?SET_USER_LIMITS */
 
 
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
@@ -1614,7 +1621,7 @@ png_set_benign_errors(png_structrp png_ptr, int allowed)
     * is the default behavior if png_set_benign_errors() is not called).
     */
 
-   if (allowed)
+   if (allowed != 0)
       png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN |
          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN;
 
@@ -1622,14 +1629,14 @@ png_set_benign_errors(png_structrp png_ptr, int allowed)
       png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
          PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
 }
-#endif /* PNG_BENIGN_ERRORS_SUPPORTED */
+#endif /* BENIGN_ERRORS */
 
 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
    /* Whether to report invalid palette index; added at libng-1.5.10.
     * It is possible for an indexed (color-type==3) PNG file to contain
     * pixels with invalid (out-of-range) indexes if the PLTE chunk has
     * fewer entries than the image's bit-depth would allow. We recover
-    * from this gracefully by filling any incomplete palette with zeroes
+    * from this gracefully by filling any incomplete palette with zeros
     * (opaque black).  By default, when this occurs libpng will issue
     * a benign error.  This API can be used to override that behavior.
     */
@@ -1645,4 +1652,4 @@ png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
       png_ptr->num_palette_max = -1;
 }
 #endif
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* READ || WRITE */

pngstruct.h

@@ -1,7 +1,7 @@
 
 /* pngstruct.h - header file for PNG reference library
  *
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *

pngtest.c

@@ -1,8 +1,8 @@
 
 /* pngtest.c - a simple test program to test libpng
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.15 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -43,8 +43,35 @@
 
 #include "png.h"
 
-#ifdef PNG_READ_SUPPORTED /* else nothing can be done */
-#include PNG_ZLIB_HEADER /* defined by pnglibconf.h */
+/* Known chunks that exist in pngtest.png must be supported or pngtest will fail
+ * simply as a result of re-ordering them.  This may be fixed in 1.7
+ *
+ * pngtest allocates a single row buffer for each row and overwrites it,
+ * therefore if the write side doesn't support the writing of interlaced images
+ * nothing can be done for an interlaced image (and the code below will fail
+ * horribly trying to write extra data after writing garbage).
+ */
+#if defined PNG_READ_SUPPORTED && /* else nothing can be done */\
+   defined PNG_READ_bKGD_SUPPORTED &&\
+   defined PNG_READ_cHRM_SUPPORTED &&\
+   defined PNG_READ_gAMA_SUPPORTED &&\
+   defined PNG_READ_oFFs_SUPPORTED &&\
+   defined PNG_READ_pCAL_SUPPORTED &&\
+   defined PNG_READ_pHYs_SUPPORTED &&\
+   defined PNG_READ_sBIT_SUPPORTED &&\
+   defined PNG_READ_sCAL_SUPPORTED &&\
+   defined PNG_READ_sRGB_SUPPORTED &&\
+   defined PNG_READ_tEXt_SUPPORTED &&\
+   defined PNG_READ_tIME_SUPPORTED &&\
+   defined PNG_READ_zTXt_SUPPORTED &&\
+   defined PNG_WRITE_INTERLACING_SUPPORTED
+
+#ifdef PNG_ZLIB_HEADER
+#  include PNG_ZLIB_HEADER /* defined by pnglibconf.h from 1.7 */
+#else
+#  include "zlib.h"
+#endif
+
 /* Copied from pngpriv.h but only used in error messages below. */
 #ifndef PNG_ZBUF_SIZE
 #  define PNG_ZBUF_SIZE 8192
@@ -256,7 +283,8 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
        png_uint_32 n, nstop;
        int channel;
        int color_channels = row_info->channels;
-       if (row_info->color_type > 3)color_channels--;
+       if (row_info->color_type > 3)
+          color_channels--;
 
        for (n = 0, nstop=row_info->width; n<nstop; n++)
        {
@@ -283,7 +311,7 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
        }
     }
 }
-#endif /* PNG_WRITE_USER_TRANSFORM_SUPPORTED */
+#endif /* WRITE_USER_TRANSFORM */
 
 #ifndef PNG_STDIO_SUPPORTED
 /* START of code to validate stdio-free compilation */
@@ -332,7 +360,7 @@ pngtest_check_io_state(png_structp png_ptr, png_size_t data_length,
    default:
       err = 1;  /* uninitialized */
    }
-   if (err)
+   if (err != 0)
       png_error(png_ptr, "Bad I/O state or buffer size");
 }
 #endif
@@ -392,7 +420,7 @@ pngtest_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
    pngtest_check_io_state(png_ptr, length, PNG_IO_WRITING);
 #endif
 }
-#endif /* !PNG_STDIO_SUPPORTED */
+#endif /* !STDIO */
 
 /* This function is called when there is a warning, but the library thinks
  * it can continue anyway.  Replacement functions don't have to do anything
@@ -513,7 +541,7 @@ PNGCBAPI png_debug_malloc(png_structp png_ptr, png_alloc_size_t size)
       /* Make sure the caller isn't assuming zeroed memory. */
       memset(pinfo->pointer, 0xdd, pinfo->size);
 
-      if (verbose)
+      if (verbose != 0)
          printf("png_malloc %lu bytes at %p\n", (unsigned long)size,
             pinfo->pointer);
 
@@ -553,14 +581,15 @@ png_debug_free(png_structp png_ptr, png_voidp ptr)
             /* We must free the list element too, but first kill
                the memory that is to be freed. */
             memset(ptr, 0x55, pinfo->size);
-            png_free_default(png_ptr, pinfo);
+            if (pinfo != NULL)
+               free(pinfo);
             pinfo = NULL;
             break;
          }
 
          if (pinfo->next == NULL)
          {
-            fprintf(STDERR, "Pointer %x not found\n", (unsigned int)ptr);
+            fprintf(STDERR, "Pointer %p not found\n", ptr);
             break;
          }
 
@@ -569,13 +598,14 @@ png_debug_free(png_structp png_ptr, png_voidp ptr)
    }
 
    /* Finally free the data. */
-   if (verbose)
+   if (verbose != 0)
       printf("Freeing %p\n", ptr);
 
-   png_free_default(png_ptr, ptr);
+   if (ptr != NULL)
+      free(ptr);
    ptr = NULL;
 }
-#endif /* PNG_USER_MEM_SUPPORTED && PNG_DEBUG */
+#endif /* USER_MEM && DEBUG */
 /* END of code to test memory allocation/deallocation */
 
 
@@ -614,16 +644,16 @@ set_location(png_structp png_ptr, struct user_chunk_data *data, int what)
 {
    int location;
 
-   if ((data->location[0] & what) || (data->location[1] & what))
+   if ((data->location[0] & what) != 0 || (data->location[1] & what) != 0)
       return 0; /* already have one of these */
 
-   /* Find where we are (the code below zeros info_ptr to indicate that the
+   /* Find where we are (the code below zeroes info_ptr to indicate that the
     * chunks before the first IDAT have been read.)
     */
    if (data->info_ptr == NULL) /* after IDAT */
       location = what | after_IDAT;
 
-   else if (png_get_valid(png_ptr, data->info_ptr, PNG_INFO_PLTE))
+   else if (png_get_valid(png_ptr, data->info_ptr, PNG_INFO_PLTE) != 0)
       location = what | before_IDAT;
 
    else
@@ -638,8 +668,8 @@ set_location(png_structp png_ptr, struct user_chunk_data *data, int what)
    return 1; /* handled */
 }
 
-static int PNGCBAPI read_user_chunk_callback(png_struct *png_ptr,
-   png_unknown_chunkp chunk)
+static int PNGCBAPI
+read_user_chunk_callback(png_struct *png_ptr, png_unknown_chunkp chunk)
 {
    struct user_chunk_data *my_user_chunk_data =
       (struct user_chunk_data*)png_get_user_chunk_ptr(png_ptr);
@@ -670,7 +700,7 @@ static int PNGCBAPI read_user_chunk_callback(png_struct *png_ptr,
          if (chunk->data[0] != 0 && chunk->data[0] != 1)
             return (-1);  /* Invalid mode */
 
-         if (set_location(png_ptr, my_user_chunk_data, have_sTER))
+         if (set_location(png_ptr, my_user_chunk_data, have_sTER) != 0)
          {
             my_user_chunk_data->sTER_mode=chunk->data[0];
             return (1);
@@ -689,7 +719,7 @@ static int PNGCBAPI read_user_chunk_callback(png_struct *png_ptr,
    if (chunk->size != 9)
       return (-1); /* Error return */
 
-   if (!set_location(png_ptr, my_user_chunk_data, have_vpAg))
+   if (set_location(png_ptr, my_user_chunk_data, have_vpAg) == 0)
       return (0);  /* duplicate vpAg */
 
    my_user_chunk_data->vpAg_width = png_get_uint_31(png_ptr, chunk->data);
@@ -703,22 +733,22 @@ static int PNGCBAPI read_user_chunk_callback(png_struct *png_ptr,
 static void
 write_sTER_chunk(png_structp write_ptr)
 {
-   png_byte png_sTER[5] = {115,  84,  69,  82, '\0'};
+   png_byte sTER[5] = {115,  84,  69,  82, '\0'};
 
-   if (verbose)
+   if (verbose != 0)
       fprintf(STDERR, "\n stereo mode = %d\n", user_chunk_data.sTER_mode);
 
-   png_write_chunk(write_ptr, png_sTER, &user_chunk_data.sTER_mode, 1);
+   png_write_chunk(write_ptr, sTER, &user_chunk_data.sTER_mode, 1);
 }
 
 static void
 write_vpAg_chunk(png_structp write_ptr)
 {
-   png_byte png_vpAg[5] = {118, 112,  65, 103, '\0'};
+   png_byte vpAg[5] = {118, 112,  65, 103, '\0'};
 
    png_byte vpag_chunk_data[9];
 
-   if (verbose)
+   if (verbose != 0)
       fprintf(STDERR, " vpAg = %lu x %lu, units = %d\n",
         (unsigned long)user_chunk_data.vpAg_width,
         (unsigned long)user_chunk_data.vpAg_height,
@@ -727,7 +757,7 @@ write_vpAg_chunk(png_structp write_ptr)
    png_save_uint_32(vpag_chunk_data, user_chunk_data.vpAg_width);
    png_save_uint_32(vpag_chunk_data + 4, user_chunk_data.vpAg_height);
    vpag_chunk_data[8] = user_chunk_data.vpAg_units;
-   png_write_chunk(write_ptr, png_vpAg, vpag_chunk_data, 9);
+   png_write_chunk(write_ptr, vpAg, vpag_chunk_data, 9);
 }
 
 static void
@@ -750,7 +780,7 @@ write_chunks(png_structp write_ptr, int location)
          write_vpAg_chunk(write_ptr);
    }
 }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */
 #else /* !PNG_READ_USER_CHUNKS_SUPPORTED */
 #  define write_chunks(pp,loc) ((void)0)
 #endif
@@ -808,6 +838,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    png_structp write_ptr;
    png_infop write_info_ptr;
    png_infop write_end_info_ptr;
+   int interlace_preserved = 1;
 #else
    png_structp write_ptr = NULL;
    png_infop write_info_ptr = NULL;
@@ -816,7 +847,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    png_bytep row_buf;
    png_uint_32 y;
    png_uint_32 width, height;
-   int num_pass, pass;
+   int num_pass = 1, pass;
    int bit_depth, color_type;
 
    row_buf = NULL;
@@ -908,7 +939,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 #endif
 #endif
 
-   if (strict)
+   if (strict != 0)
    {
       /* Treat png_benign_error() as errors on read */
       png_set_benign_errors(read_ptr, 0);
@@ -924,7 +955,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
        */
    }
 
-   else if (relaxed)
+   else if (relaxed != 0)
    {
       /* Allow application (pngtest) errors and warnings to pass */
       png_set_benign_errors(read_ptr, 1);
@@ -1019,13 +1050,29 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       int interlace_type, compression_type, filter_type;
 
       if (png_get_IHDR(read_ptr, read_info_ptr, &width, &height, &bit_depth,
-          &color_type, &interlace_type, &compression_type, &filter_type))
+          &color_type, &interlace_type, &compression_type, &filter_type) != 0)
       {
          png_set_IHDR(write_ptr, write_info_ptr, width, height, bit_depth,
-#ifdef PNG_WRITE_INTERLACING_SUPPORTED
             color_type, interlace_type, compression_type, filter_type);
-#else
-            color_type, PNG_INTERLACE_NONE, compression_type, filter_type);
+#ifndef PNG_READ_INTERLACING_SUPPORTED
+         /* num_pass will not be set below, set it here if the image is
+          * interlaced: what happens is that write interlacing is *not* turned
+          * on an the partial interlaced rows are written directly.
+          */
+         switch (interlace_type)
+         {
+            case PNG_INTERLACE_NONE:
+               num_pass = 1;
+               break;
+
+            case PNG_INTERLACE_ADAM7:
+               num_pass = 7;
+                break;
+
+            default:
+                png_error(read_ptr, "invalid interlace type");
+                /*NOT REACHED*/
+         }
 #endif
       }
    }
@@ -1036,7 +1083,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
          blue_y;
 
       if (png_get_cHRM_fixed(read_ptr, read_info_ptr, &white_x, &white_y,
-         &red_x, &red_y, &green_x, &green_y, &blue_x, &blue_y))
+         &red_x, &red_y, &green_x, &green_y, &blue_x, &blue_y) != 0)
       {
          png_set_cHRM_fixed(write_ptr, write_info_ptr, white_x, white_y, red_x,
             red_y, green_x, green_y, blue_x, blue_y);
@@ -1047,7 +1094,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       png_fixed_point gamma;
 
-      if (png_get_gAMA_fixed(read_ptr, read_info_ptr, &gamma))
+      if (png_get_gAMA_fixed(read_ptr, read_info_ptr, &gamma) != 0)
          png_set_gAMA_fixed(write_ptr, write_info_ptr, gamma);
    }
 #endif
@@ -1059,7 +1106,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
          blue_y;
 
       if (png_get_cHRM(read_ptr, read_info_ptr, &white_x, &white_y, &red_x,
-         &red_y, &green_x, &green_y, &blue_x, &blue_y))
+         &red_y, &green_x, &green_y, &blue_x, &blue_y) != 0)
       {
          png_set_cHRM(write_ptr, write_info_ptr, white_x, white_y, red_x,
             red_y, green_x, green_y, blue_x, blue_y);
@@ -1070,7 +1117,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       double gamma;
 
-      if (png_get_gAMA(read_ptr, read_info_ptr, &gamma))
+      if (png_get_gAMA(read_ptr, read_info_ptr, &gamma) != 0)
          png_set_gAMA(write_ptr, write_info_ptr, gamma);
    }
 #endif
@@ -1084,7 +1131,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       int compression_type;
 
       if (png_get_iCCP(read_ptr, read_info_ptr, &name, &compression_type,
-                      &profile, &proflen))
+                      &profile, &proflen) != 0)
       {
          png_set_iCCP(write_ptr, write_info_ptr, name, compression_type,
                       profile, proflen);
@@ -1095,7 +1142,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       int intent;
 
-      if (png_get_sRGB(read_ptr, read_info_ptr, &intent))
+      if (png_get_sRGB(read_ptr, read_info_ptr, &intent) != 0)
          png_set_sRGB(write_ptr, write_info_ptr, intent);
    }
 #endif
@@ -1103,14 +1150,14 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_colorp palette;
       int num_palette;
 
-      if (png_get_PLTE(read_ptr, read_info_ptr, &palette, &num_palette))
+      if (png_get_PLTE(read_ptr, read_info_ptr, &palette, &num_palette) != 0)
          png_set_PLTE(write_ptr, write_info_ptr, palette, num_palette);
    }
 #ifdef PNG_bKGD_SUPPORTED
    {
       png_color_16p background;
 
-      if (png_get_bKGD(read_ptr, read_info_ptr, &background))
+      if (png_get_bKGD(read_ptr, read_info_ptr, &background) != 0)
       {
          png_set_bKGD(write_ptr, write_info_ptr, background);
       }
@@ -1120,7 +1167,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       png_uint_16p hist;
 
-      if (png_get_hIST(read_ptr, read_info_ptr, &hist))
+      if (png_get_hIST(read_ptr, read_info_ptr, &hist) != 0)
          png_set_hIST(write_ptr, write_info_ptr, hist);
    }
 #endif
@@ -1130,7 +1177,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       int unit_type;
 
       if (png_get_oFFs(read_ptr, read_info_ptr, &offset_x, &offset_y,
-          &unit_type))
+          &unit_type) != 0)
       {
          png_set_oFFs(write_ptr, write_info_ptr, offset_x, offset_y, unit_type);
       }
@@ -1144,7 +1191,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       int type, nparams;
 
       if (png_get_pCAL(read_ptr, read_info_ptr, &purpose, &X0, &X1, &type,
-         &nparams, &units, &params))
+         &nparams, &units, &params) != 0)
       {
          png_set_pCAL(write_ptr, write_info_ptr, purpose, X0, X1, type,
             nparams, units, params);
@@ -1156,7 +1203,8 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_uint_32 res_x, res_y;
       int unit_type;
 
-      if (png_get_pHYs(read_ptr, read_info_ptr, &res_x, &res_y, &unit_type))
+      if (png_get_pHYs(read_ptr, read_info_ptr, &res_x, &res_y,
+          &unit_type) != 0)
          png_set_pHYs(write_ptr, write_info_ptr, res_x, res_y, unit_type);
    }
 #endif
@@ -1164,7 +1212,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       png_color_8p sig_bit;
 
-      if (png_get_sBIT(read_ptr, read_info_ptr, &sig_bit))
+      if (png_get_sBIT(read_ptr, read_info_ptr, &sig_bit) != 0)
          png_set_sBIT(write_ptr, write_info_ptr, sig_bit);
    }
 #endif
@@ -1176,7 +1224,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       double scal_width, scal_height;
 
       if (png_get_sCAL(read_ptr, read_info_ptr, &unit, &scal_width,
-         &scal_height))
+         &scal_height) != 0)
       {
          png_set_sCAL(write_ptr, write_info_ptr, unit, scal_width, scal_height);
       }
@@ -1188,7 +1236,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_charp scal_width, scal_height;
 
       if (png_get_sCAL_s(read_ptr, read_info_ptr, &unit, &scal_width,
-          &scal_height))
+          &scal_height) != 0)
       {
          png_set_sCAL_s(write_ptr, write_info_ptr, unit, scal_width,
              scal_height);
@@ -1208,7 +1256,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 
          pngtest_check_text_support(read_ptr, text_ptr, num_text);
 
-         if (verbose)
+         if (verbose != 0)
          {
             int i;
 
@@ -1228,11 +1276,11 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       png_timep mod_time;
 
-      if (png_get_tIME(read_ptr, read_info_ptr, &mod_time))
+      if (png_get_tIME(read_ptr, read_info_ptr, &mod_time) != 0)
       {
          png_set_tIME(write_ptr, write_info_ptr, mod_time);
 #ifdef PNG_TIME_RFC1123_SUPPORTED
-         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time))
+         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time) != 0)
             tIME_string[(sizeof tIME_string) - 1] = '\0';
 
          else
@@ -1242,7 +1290,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
          }
 
          tIME_chunk_present++;
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
       }
    }
 #endif
@@ -1253,7 +1301,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_color_16p trans_color;
 
       if (png_get_tRNS(read_ptr, read_info_ptr, &trans_alpha, &num_trans,
-         &trans_color))
+         &trans_color) != 0)
       {
          int sample_max = (1 << bit_depth);
          /* libpng doesn't reject a tRNS chunk with out-of-range samples */
@@ -1274,7 +1322,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       int num_unknowns = png_get_unknown_chunks(read_ptr, read_info_ptr,
          &unknowns);
 
-      if (num_unknowns)
+      if (num_unknowns != 0)
       {
          png_set_unknown_chunks(write_ptr, write_info_ptr, unknowns,
            num_unknowns);
@@ -1318,14 +1366,10 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 #endif /* SINGLE_ROWBUF_ALLOC */
    pngtest_debug("Writing row data");
 
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
-  defined(PNG_WRITE_INTERLACING_SUPPORTED)
+#ifdef PNG_READ_INTERLACING_SUPPORTED
    num_pass = png_set_interlace_handling(read_ptr);
-#  ifdef PNG_WRITE_SUPPORTED
-   png_set_interlace_handling(write_ptr);
-#  endif
-#else
-   num_pass = 1;
+   if (png_set_interlace_handling(write_ptr) != num_pass)
+      png_error(write_ptr, "png_set_interlace_handling: inconsistent num_pass");
 #endif
 
 #ifdef PNGTEST_TIMING
@@ -1340,11 +1384,12 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       {
 #ifndef SINGLE_ROWBUF_ALLOC
          pngtest_debug2("Allocating row buffer (pass %d, y = %u)...", pass, y);
+
          row_buf = (png_bytep)png_malloc(read_ptr,
             png_get_rowbytes(read_ptr, read_info_ptr));
 
-         pngtest_debug2("\t0x%08lx (%u bytes)", (unsigned long)row_buf,
-            png_get_rowbytes(read_ptr, read_info_ptr));
+         pngtest_debug2("\t0x%08lx (%lu bytes)", (unsigned long)row_buf,
+            (unsigned long)png_get_rowbytes(read_ptr, read_info_ptr));
 
 #endif /* !SINGLE_ROWBUF_ALLOC */
          png_read_rows(read_ptr, (png_bytepp)&row_buf, NULL, 1);
@@ -1361,7 +1406,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
          t_encode += (t_stop - t_start);
          t_start = t_stop;
 #endif
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */
 
 #ifndef SINGLE_ROWBUF_ALLOC
          pngtest_debug2("Freeing row buffer (pass %d, y = %u)", pass, y);
@@ -1371,11 +1416,13 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       }
    }
 
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-   png_free_data(read_ptr, read_info_ptr, PNG_FREE_UNKN, -1);
-#endif
-#ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
-   png_free_data(write_ptr, write_info_ptr, PNG_FREE_UNKN, -1);
+#ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
+#  ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
+      png_free_data(read_ptr, read_info_ptr, PNG_FREE_UNKN, -1);
+#  endif
+#  ifdef PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED
+      png_free_data(write_ptr, write_info_ptr, PNG_FREE_UNKN, -1);
+#  endif
 #endif
 
    pngtest_debug("Reading and writing end_info data");
@@ -1392,7 +1439,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 
          pngtest_check_text_support(read_ptr, text_ptr, num_text);
 
-         if (verbose)
+         if (verbose != 0)
          {
             int i;
 
@@ -1412,11 +1459,11 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       png_timep mod_time;
 
-      if (png_get_tIME(read_ptr, end_info_ptr, &mod_time))
+      if (png_get_tIME(read_ptr, end_info_ptr, &mod_time) != 0)
       {
          png_set_tIME(write_ptr, write_end_info_ptr, mod_time);
 #ifdef PNG_TIME_RFC1123_SUPPORTED
-         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time))
+         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time) != 0)
             tIME_string[(sizeof tIME_string) - 1] = '\0';
 
          else
@@ -1426,7 +1473,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
          }
 
          tIME_chunk_present++;
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
       }
    }
 #endif
@@ -1436,7 +1483,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       int num_unknowns = png_get_unknown_chunks(read_ptr, end_info_ptr,
          &unknowns);
 
-      if (num_unknowns)
+      if (num_unknowns != 0)
       {
          png_set_unknown_chunks(write_ptr, write_end_info_ptr, unknowns,
            num_unknowns);
@@ -1477,7 +1524,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 #endif
 
 #ifdef PNG_EASY_ACCESS_SUPPORTED
-   if (verbose)
+   if (verbose != 0)
    {
       png_uint_32 iwidth, iheight;
       iwidth = png_get_image_width(write_ptr, write_info_ptr);
@@ -1555,15 +1602,14 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    }
 
 #ifdef PNG_WRITE_SUPPORTED /* else nothing was written */
+   if (interlace_preserved != 0) /* else the files will be changed */
    {
-      int wrote_question = 0;
-
       for (;;)
       {
+         static int wrote_question = 0;
          png_size_t num_in, num_out;
          char inbuf[256], outbuf[256];
 
-
          num_in = fread(inbuf, 1, sizeof inbuf, fpin);
          num_out = fread(outbuf, 1, sizeof outbuf, fpout);
 
@@ -1595,7 +1641,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
               return (0);
          }
 
-         if (!num_in)
+         if (num_in == 0)
             break;
 
          if (memcmp(inbuf, outbuf, num_in))
@@ -1632,7 +1678,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
          }
       }
    }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */
 
    FCLOSE(fpin);
    FCLOSE(fpout);
@@ -1737,10 +1783,11 @@ main(int argc, char *argv[])
       }
    }
 
-   if (!multiple && argc == 3 + verbose)
+   if (multiple == 0 && argc == 3 + verbose)
      outname = argv[2 + verbose];
 
-   if ((!multiple && argc > 3 + verbose) || (multiple && argc < 2))
+   if ((multiple == 0 && argc > 3 + verbose) ||
+       (multiple != 0 && argc < 2))
    {
      fprintf(STDERR,
        "usage: %s [infile.png] [outfile.png]\n\t%s -m {infile.png}\n",
@@ -1752,7 +1799,7 @@ main(int argc, char *argv[])
      exit(1);
    }
 
-   if (multiple)
+   if (multiple != 0)
    {
       int i;
 #if defined(PNG_USER_MEM_SUPPORTED) && PNG_DEBUG
@@ -1762,6 +1809,9 @@ main(int argc, char *argv[])
       {
          int kerror;
          fprintf(STDERR, "\n Testing %s:", argv[i]);
+#if PNG_DEBUG > 0
+         fprintf(STDERR, "\n");
+#endif
          kerror = test_one_file(argv[i], outname);
          if (kerror == 0)
          {
@@ -1776,7 +1826,7 @@ main(int argc, char *argv[])
 #endif
 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
             for (k = 0; k<256; k++)
-               if (filters_used[k])
+               if (filters_used[k] != 0)
                   fprintf(STDERR, " Filter %d was used %lu times\n",
                      k, (unsigned long)filters_used[k]);
 #endif
@@ -1785,7 +1835,7 @@ main(int argc, char *argv[])
             fprintf(STDERR, " tIME = %s\n", tIME_string);
 
          tIME_chunk_present = 0;
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
          }
 
          else
@@ -1807,9 +1857,9 @@ main(int argc, char *argv[])
 
             while (pinfo != NULL)
             {
-               fprintf(STDERR, " %lu bytes at %x\n",
+               fprintf(STDERR, " %lu bytes at %p\n",
                  (unsigned long)pinfo->size,
-                 (unsigned int)pinfo->pointer);
+                 pinfo->pointer);
                pinfo = pinfo->next;
             }
          }
@@ -1843,7 +1893,12 @@ main(int argc, char *argv[])
             status_dots_requested = 0;
 
          if (i == 0 || verbose == 1 || ierror != 0)
+         {
             fprintf(STDERR, "\n Testing %s:", inname);
+#if PNG_DEBUG > 0
+            fprintf(STDERR, "\n");
+#endif
+         }
 
          kerror = test_one_file(inname, outname);
 
@@ -1862,21 +1917,26 @@ main(int argc, char *argv[])
 #endif
 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
                 for (k = 0; k<256; k++)
-                   if (filters_used[k])
+                   if (filters_used[k] != 0)
                       fprintf(STDERR, " Filter %d was used %lu times\n",
                          k, (unsigned long)filters_used[k]);
 #endif
 #ifdef PNG_TIME_RFC1123_SUPPORTED
              if (tIME_chunk_present != 0)
                 fprintf(STDERR, " tIME = %s\n", tIME_string);
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
             }
          }
 
          else
          {
             if (verbose == 0 && i != 2)
+            {
                fprintf(STDERR, "\n Testing %s:", inname);
+#if PNG_DEBUG > 0
+               fprintf(STDERR, "\n");
+#endif
+            }
 
             fprintf(STDERR, " FAIL\n");
             ierror += kerror;
@@ -1895,8 +1955,8 @@ main(int argc, char *argv[])
 
              while (pinfo != NULL)
              {
-                fprintf(STDERR, " %lu bytes at %x\n",
-                   (unsigned long)pinfo->size, (unsigned int)pinfo->pointer);
+                fprintf(STDERR, " %lu bytes at %p\n",
+                   (unsigned long)pinfo->size, pinfo->pointer);
                 pinfo = pinfo->next;
              }
           }
@@ -1942,9 +2002,10 @@ main(void)
 {
    fprintf(STDERR,
       " test ignored because libpng was not built with read support\n");
-   return 0;
+   /* And skip this test */
+   return PNG_LIBPNG_VER < 10600 ? 0 : 77;
 }
 #endif
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_7_0beta08 Your_png_h_is_not_version_1_7_0beta08;
+typedef png_libpng_version_1_7_0beta41 Your_png_h_is_not_version_1_7_0beta41;

pngtrans.c

@@ -1,8 +1,8 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.15 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -100,7 +100,7 @@ png_set_interlace_handling(png_structrp png_ptr)
 {
    png_debug(1, "in png_set_interlace handling");
 
-   if (png_ptr && png_ptr->interlaced)
+   if (png_ptr != 0 && png_ptr->interlaced != 0)
    {
       png_ptr->transformations |= PNG_INTERLACE;
       return (7);
@@ -127,7 +127,7 @@ png_set_filler(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
    /* In libpng 1.6 it is possible to determine whether this is a read or write
     * operation and therefore to do more checking here for a valid call.
     */
-   if (png_ptr->mode & PNG_IS_READ_STRUCT)
+   if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
    {
 #     ifdef PNG_READ_FILLER_SUPPORTED
          /* On read png_set_filler is always valid, regardless of the base PNG
@@ -210,7 +210,7 @@ png_set_add_alpha(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
 
    png_set_filler(png_ptr, filler, filler_loc);
    /* The above may fail to do anything. */
-   if (png_ptr->transformations & PNG_FILLER)
+   if ((png_ptr->transformations & PNG_FILLER) != 0)
       png_ptr->transformations |= PNG_ADD_ALPHA;
 }
 
@@ -327,9 +327,16 @@ png_do_swap(png_row_infop row_info, png_bytep row)
 
       for (i = 0; i < istop; i++, rp += 2)
       {
+#ifdef PNG_BUILTIN_BSWAP16_SUPPORTED
+         /* Feature added to libpng-1.6.11 for testing purposes, not
+          * enabled by default.
+          */
+         *(png_uint_16*)rp = __builtin_bswap16(*(png_uint_16*)rp);
+#else
          png_byte t = *rp;
          *rp = *(rp + 1);
          *(rp + 1) = t;
+#endif
       }
    }
 }
@@ -471,7 +478,7 @@ png_do_packswap(png_row_infop row_info, png_bytep row)
          *rp = table[*rp];
    }
 }
-#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */
+#endif /* READ_PACKSWAP or WRITE_PACKSWAP */
 
 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
     defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
@@ -503,7 +510,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
    {
       if (row_info->bit_depth == 8)
       {
-         if (at_start) /* Skip initial filler */
+         if (at_start != 0) /* Skip initial filler */
             ++sp;
          else          /* Skip initial channel and, for sp, the filler */
             sp += 2, ++dp;
@@ -517,7 +524,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
 
       else if (row_info->bit_depth == 16)
       {
-         if (at_start) /* Skip initial filler */
+         if (at_start != 0) /* Skip initial filler */
             sp += 2;
          else          /* Skip initial channel and, for sp, the filler */
             sp += 4, dp += 2;
@@ -543,7 +550,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
    {
       if (row_info->bit_depth == 8)
       {
-         if (at_start) /* Skip initial filler */
+         if (at_start != 0) /* Skip initial filler */
             ++sp;
          else          /* Skip initial channels and, for sp, the filler */
             sp += 4, dp += 3;
@@ -557,7 +564,7 @@ png_do_strip_channel(png_row_infop row_info, png_bytep row, int at_start)
 
       else if (row_info->bit_depth == 16)
       {
-         if (at_start) /* Skip initial filler */
+         if (at_start != 0) /* Skip initial filler */
             sp += 2;
          else          /* Skip initial channels and, for sp, the filler */
             sp += 8, dp += 6;
@@ -598,7 +605,7 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
 {
    png_debug(1, "in png_do_bgr");
 
-   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
+   if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
    {
       png_uint_32 row_width = row_info->width;
       if (row_info->bit_depth == 8)
@@ -668,7 +675,7 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
 #endif
    }
 }
-#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+#endif /* READ_BGR or WRITE_BGR */
 
 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
     defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
@@ -771,7 +778,7 @@ png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info)
       }
    }
 }
-#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
+#endif /* CHECK_FOR_INVALID_INDEX */
 
 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
     defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
@@ -821,7 +828,7 @@ png_get_user_transform_ptr(png_const_structrp png_ptr)
 png_uint_32 PNGAPI
 png_get_current_row_number(png_const_structrp png_ptr)
 {
-   /* See the comments in png.h - this is the sub-image row when reading and
+   /* See the comments in png.h - this is the sub-image row when reading an
     * interlaced image.
     */
    if (png_ptr != NULL)
@@ -837,7 +844,7 @@ png_get_current_pass_number(png_const_structrp png_ptr)
       return png_ptr->pass;
    return 8; /* invalid */
 }
-#endif /* PNG_USER_TRANSFORM_INFO_SUPPORTED */
-#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
+#endif /* USER_TRANSFORM_INFO */
+#endif /* READ_USER_TRANSFORM ||
           PNG_WRITE_USER_TRANSFORM_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* READ || WRITE */

pngwio.c

@@ -1,8 +1,8 @@
 
 /* pngwio.c - functions for data output
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.9 [February 6, 2014]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -149,7 +149,9 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
 #  else
    png_ptr->output_flush_fn = output_flush_fn;
 #  endif
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+#else
+   PNG_UNUSED(output_flush_fn)
+#endif /* WRITE_FLUSH */
 
 #ifdef PNG_READ_SUPPORTED
    /* It is an error to read while writing a png file */
@@ -163,4 +165,4 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
    }
 #endif
 }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */

pngwrite.c

@@ -2,7 +2,7 @@
 /* pngwrite.c - general routines to write a PNG file
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -24,7 +24,7 @@ static void
 write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
    unsigned int where)
 {
-   if (info_ptr->unknown_chunks_num)
+   if (info_ptr->unknown_chunks_num != 0)
    {
       png_const_unknown_chunkp up;
 
@@ -33,7 +33,7 @@ write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
       for (up = info_ptr->unknown_chunks;
            up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
            ++up)
-         if (up->location & where)
+         if ((up->location & where) != 0)
       {
          /* If per-chunk unknown chunk handling is enabled use it, otherwise
           * just write the chunks the application has set.
@@ -69,7 +69,7 @@ write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
       }
    }
 }
-#endif /* PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED */
+#endif /* WRITE_UNKNOWN_CHUNKS */
 
 /* Writes all the PNG information.  This is the suggested way to use the
  * library.  If you have a new chunk to add, make a function to write it,
@@ -88,14 +88,14 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+   if ((png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE) == 0)
    {
    /* Write PNG signature */
    png_write_sig(png_ptr);
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-   if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \
-       (png_ptr->mng_features_permitted))
+   if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) != 0 && \
+       png_ptr->mng_features_permitted != 0)
    {
       png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
       png_ptr->mng_features_permitted = 0;
@@ -129,9 +129,9 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
     */
 #ifdef PNG_GAMMA_SUPPORTED
 #  ifdef PNG_WRITE_gAMA_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) &&
-         (info_ptr->valid & PNG_INFO_gAMA))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+          (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) != 0 &&
+          (info_ptr->valid & PNG_INFO_gAMA) != 0)
          png_write_gAMA_fixed(png_ptr, info_ptr->colorspace.gamma);
 #  endif
 #endif
@@ -141,11 +141,11 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
     * and it matches one of the known sRGB ones issue a warning.
     */
 #  ifdef PNG_WRITE_iCCP_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->valid & PNG_INFO_iCCP))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+          (info_ptr->valid & PNG_INFO_iCCP) != 0)
       {
 #        ifdef PNG_WRITE_sRGB_SUPPORTED
-            if (info_ptr->valid & PNG_INFO_sRGB)
+            if ((info_ptr->valid & PNG_INFO_sRGB) != 0)
                png_app_warning(png_ptr,
                   "profile matches sRGB but writing iCCP instead");
 #        endif
@@ -159,22 +159,22 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
 #  endif
 
 #  ifdef PNG_WRITE_sRGB_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->valid & PNG_INFO_sRGB))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+          (info_ptr->valid & PNG_INFO_sRGB) != 0)
          png_write_sRGB(png_ptr, info_ptr->colorspace.rendering_intent);
 #  endif /* WRITE_sRGB */
 #endif /* COLORSPACE */
 
 #ifdef PNG_WRITE_sBIT_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_sBIT)
+   if ((info_ptr->valid & PNG_INFO_sBIT) != 0)
       png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
 #endif
 
 #ifdef PNG_COLORSPACE_SUPPORTED
 #  ifdef PNG_WRITE_cHRM_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) &&
-         (info_ptr->valid & PNG_INFO_cHRM))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+         (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) != 0 &&
+         (info_ptr->valid & PNG_INFO_cHRM) != 0)
          png_write_cHRM_fixed(png_ptr, &info_ptr->colorspace.end_points_xy);
 #  endif
 #endif
@@ -201,19 +201,19 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
 
    png_write_info_before_PLTE(png_ptr, info_ptr);
 
-   if (info_ptr->valid & PNG_INFO_PLTE)
+   if ((info_ptr->valid & PNG_INFO_PLTE) != 0)
       png_write_PLTE(png_ptr, info_ptr->palette,
           (png_uint_32)info_ptr->num_palette);
 
-   else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   else if ((info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) !=0)
       png_error(png_ptr, "Valid palette required for paletted images");
 
 #ifdef PNG_WRITE_tRNS_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_tRNS)
+   if ((info_ptr->valid & PNG_INFO_tRNS) !=0)
    {
 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
       /* Invert the alpha channel (in tRNS) */
-      if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
+      if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0 &&
           info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       {
          int j, jend;
@@ -232,42 +232,42 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
    }
 #endif
 #ifdef PNG_WRITE_bKGD_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_bKGD)
+   if ((info_ptr->valid & PNG_INFO_bKGD) != 0)
       png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
 #endif
 
 #ifdef PNG_WRITE_hIST_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_hIST)
+   if ((info_ptr->valid & PNG_INFO_hIST) != 0)
       png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
 #endif
 
 #ifdef PNG_WRITE_oFFs_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_oFFs)
+   if ((info_ptr->valid & PNG_INFO_oFFs) != 0)
       png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
           info_ptr->offset_unit_type);
 #endif
 
 #ifdef PNG_WRITE_pCAL_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_pCAL)
+   if ((info_ptr->valid & PNG_INFO_pCAL) != 0)
       png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
           info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
           info_ptr->pcal_units, info_ptr->pcal_params);
 #endif
 
 #ifdef PNG_WRITE_sCAL_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_sCAL)
+   if ((info_ptr->valid & PNG_INFO_sCAL) != 0)
       png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
           info_ptr->scal_s_width, info_ptr->scal_s_height);
 #endif /* sCAL */
 
 #ifdef PNG_WRITE_pHYs_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_pHYs)
+   if ((info_ptr->valid & PNG_INFO_pHYs) != 0)
       png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
           info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
 #endif /* pHYs */
 
 #ifdef PNG_WRITE_tIME_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_tIME)
+   if ((info_ptr->valid & PNG_INFO_tIME) != 0)
    {
       png_write_tIME(png_ptr, &(info_ptr->mod_time));
       png_ptr->mode |= PNG_WROTE_tIME;
@@ -275,7 +275,7 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
 #endif /* tIME */
 
 #ifdef PNG_WRITE_sPLT_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_sPLT)
+   if ((info_ptr->valid & PNG_INFO_sPLT) != 0)
       for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
          png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
 #endif /* sPLT */
@@ -297,11 +297,14 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
              info_ptr->text[i].lang,
              info_ptr->text[i].lang_key,
              info_ptr->text[i].text);
+         /* Mark this chunk as written */
+         if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+         else
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
 #else
-          png_warning(png_ptr, "Unable to write international text");
+         png_warning(png_ptr, "Unable to write international text");
 #endif
-          /* Mark this chunk as written */
-          info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
       }
 
       /* If we want a compressed text chunk */
@@ -310,13 +313,12 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
 #ifdef PNG_WRITE_zTXt_SUPPORTED
          /* Write compressed chunk */
          png_write_zTXt(png_ptr, info_ptr->text[i].key,
-             info_ptr->text[i].text, 0,
-             info_ptr->text[i].compression);
+             info_ptr->text[i].text, info_ptr->text[i].compression);
+         /* Mark this chunk as written */
+         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
 #else
          png_warning(png_ptr, "Unable to write compressed text");
 #endif
-         /* Mark this chunk as written */
-         info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
       }
 
       else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
@@ -354,7 +356,7 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
    if (png_ptr == NULL)
       return;
 
-   if (!(png_ptr->mode & PNG_HAVE_IDAT))
+   if ((png_ptr->mode & PNG_HAVE_IDAT) == 0)
       png_error(png_ptr, "No IDATs written into file");
 
 #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
@@ -370,8 +372,8 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
 #endif
 #ifdef PNG_WRITE_tIME_SUPPORTED
       /* Check to see if user has supplied a time chunk */
-      if ((info_ptr->valid & PNG_INFO_tIME) &&
-          !(png_ptr->mode & PNG_WROTE_tIME))
+      if ((info_ptr->valid & PNG_INFO_tIME) != 0 &&
+          (png_ptr->mode & PNG_WROTE_tIME) == 0)
          png_write_tIME(png_ptr, &(info_ptr->mod_time));
 
 #endif
@@ -392,11 +394,14 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
                 info_ptr->text[i].lang,
                 info_ptr->text[i].lang_key,
                 info_ptr->text[i].text);
+            /* Mark this chunk as written */
+            if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
+               info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
+            else
+               info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
 #else
             png_warning(png_ptr, "Unable to write international text");
 #endif
-            /* Mark this chunk as written */
-            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
          }
 
          else if (info_ptr->text[i].compression >= PNG_TEXT_COMPRESSION_zTXt)
@@ -404,13 +409,12 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_WRITE_zTXt_SUPPORTED
             /* Write compressed chunk */
             png_write_zTXt(png_ptr, info_ptr->text[i].key,
-                info_ptr->text[i].text, 0,
-                info_ptr->text[i].compression);
+                info_ptr->text[i].text, info_ptr->text[i].compression);
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
 #else
             png_warning(png_ptr, "Unable to write compressed text");
 #endif
-            /* Mark this chunk as written */
-            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_zTXt_WR;
          }
 
          else if (info_ptr->text[i].compression == PNG_TEXT_COMPRESSION_NONE)
@@ -419,12 +423,11 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
             /* Write uncompressed chunk */
             png_write_tEXt(png_ptr, info_ptr->text[i].key,
                 info_ptr->text[i].text, 0);
+            /* Mark this chunk as written */
+            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
 #else
             png_warning(png_ptr, "Unable to write uncompressed text");
 #endif
-
-            /* Mark this chunk as written */
-            info_ptr->text[i].compression = PNG_TEXT_COMPRESSION_NONE_WR;
          }
       }
 #endif
@@ -498,52 +501,52 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 {
    png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr,
       error_fn, warn_fn, mem_ptr, malloc_fn, free_fn);
-#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* USER_MEM */
 
-   /* Set the zlib control values to defaults; they can be overridden by the
-    * application after the struct has been created.
-    */
-   png_ptr->zbuffer_size = PNG_ZBUF_SIZE;
+   if (png_ptr != NULL)
+   {
+      /* Set the zlib control values to defaults; they can be overridden by the
+       * application after the struct has been created.
+       */
+      png_ptr->zbuffer_size = PNG_ZBUF_SIZE;
 
-   /* The 'zlib_strategy' setting is irrelevant because png_default_claim in
-    * pngwutil.c defaults it according to whether or not filters will be used,
-    * and ignores this setting.
-    */
-   png_ptr->zlib_strategy = PNG_Z_DEFAULT_STRATEGY;
-   png_ptr->zlib_level = PNG_Z_DEFAULT_COMPRESSION;
-   png_ptr->zlib_mem_level = 8;
-   png_ptr->zlib_window_bits = 15;
-   png_ptr->zlib_method = 8;
+      /* The 'zlib_strategy' setting is irrelevant because png_default_claim in
+       * pngwutil.c defaults it according to whether or not filters will be
+       * used, and ignores this setting.
+       */
+      png_ptr->zlib_strategy = PNG_Z_DEFAULT_STRATEGY;
+      png_ptr->zlib_level = PNG_Z_DEFAULT_COMPRESSION;
+      png_ptr->zlib_mem_level = 8;
+      png_ptr->zlib_window_bits = 15;
+      png_ptr->zlib_method = 8;
 
 #ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
-   png_ptr->zlib_text_strategy = PNG_TEXT_Z_DEFAULT_STRATEGY;
-   png_ptr->zlib_text_level = PNG_TEXT_Z_DEFAULT_COMPRESSION;
-   png_ptr->zlib_text_mem_level = 8;
-   png_ptr->zlib_text_window_bits = 15;
-   png_ptr->zlib_text_method = 8;
-#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
+      png_ptr->zlib_text_strategy = PNG_TEXT_Z_DEFAULT_STRATEGY;
+      png_ptr->zlib_text_level = PNG_TEXT_Z_DEFAULT_COMPRESSION;
+      png_ptr->zlib_text_mem_level = 8;
+      png_ptr->zlib_text_window_bits = 15;
+      png_ptr->zlib_text_method = 8;
+#endif /* WRITE_COMPRESSED_TEXT */
 
-   /* This is a highly dubious configuration option; by default it is off, but
-    * it may be appropriate for private builds that are testing extensions not
-    * conformant to the current specification, or of applications that must not
-    * fail to write at all costs!
-    */
-#  ifdef PNG_BENIGN_WRITE_ERRORS_SUPPORTED
+      /* This is a highly dubious configuration option; by default it is off,
+       * but it may be appropriate for private builds that are testing
+       * extensions not conformant to the current specification, or of
+       * applications that must not fail to write at all costs!
+       */
+#ifdef PNG_BENIGN_WRITE_ERRORS_SUPPORTED
       png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN;
       /* In stable builds only warn if an application error can be completely
        * handled.
        */
-#  endif
+#endif
 
-   /* App warnings are warnings in release (or release candidate) builds but
-    * are errors during development.
-    */
-#  if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
-      png_ptr->flags |= PNG_FLAG_APP_WARNINGS_WARN;
-#  endif
+      /* App warnings are warnings in release (or release candidate) builds but
+       * are errors during development.
+       */
+#if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
+         png_ptr->flags |= PNG_FLAG_APP_WARNINGS_WARN;
+#endif
 
-   if (png_ptr != NULL)
-   {
       /* TODO: delay this, it can be done in png_init_io() (if the app doesn't
        * do it itself) avoiding setting the default function if it is not
        * required.
@@ -613,6 +616,71 @@ png_write_image(png_structrp png_ptr, png_bytepp image)
    }
 }
 
+#ifdef PNG_MNG_FEATURES_SUPPORTED
+/* Performs intrapixel differencing  */
+static void
+png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_write_intrapixel");
+
+   if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
+   {
+      int bytes_per_pixel;
+      png_uint_32 row_width = row_info->width;
+      if (row_info->bit_depth == 8)
+      {
+         png_bytep rp;
+         png_uint_32 i;
+
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+            bytes_per_pixel = 3;
+
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            bytes_per_pixel = 4;
+
+         else
+            return;
+
+         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+         {
+            *(rp)     = (png_byte)((*rp       - *(rp + 1)) & 0xff);
+            *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff);
+         }
+      }
+
+#ifdef PNG_WRITE_16BIT_SUPPORTED
+      else if (row_info->bit_depth == 16)
+      {
+         png_bytep rp;
+         png_uint_32 i;
+
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+            bytes_per_pixel = 6;
+
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+            bytes_per_pixel = 8;
+
+         else
+            return;
+
+         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
+         {
+            png_uint_32 s0   = (*(rp    ) << 8) | *(rp + 1);
+            png_uint_32 s1   = (*(rp + 2) << 8) | *(rp + 3);
+            png_uint_32 s2   = (*(rp + 4) << 8) | *(rp + 5);
+            png_uint_32 red  = (png_uint_32)((s0 - s1) & 0xffffL);
+            png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL);
+            *(rp    ) = (png_byte)((red >> 8) & 0xff);
+            *(rp + 1) = (png_byte)(red & 0xff);
+            *(rp + 4) = (png_byte)((blue >> 8) & 0xff);
+            *(rp + 5) = (png_byte)(blue & 0xff);
+         }
+      }
+#endif /* WRITE_16BIT */
+   }
+}
+#endif /* MNG_FEATURES */
+
 /* Called by user to write a row of image data */
 void PNGAPI
 png_write_row(png_structrp png_ptr, png_const_bytep row)
@@ -630,44 +698,44 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
    if (png_ptr->row_number == 0 && png_ptr->pass == 0)
    {
       /* Make sure we wrote the header info */
-      if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+      if ((png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE) == 0)
          png_error(png_ptr,
              "png_write_info was never called before png_write_row");
 
       /* Check for transforms that have been set but were defined out */
 #if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
-      if (png_ptr->transformations & PNG_INVERT_MONO)
+      if ((png_ptr->transformations & PNG_INVERT_MONO) != 0)
          png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined");
 #endif
 
 #if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
-      if (png_ptr->transformations & PNG_FILLER)
+      if ((png_ptr->transformations & PNG_FILLER) != 0)
          png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined");
 #endif
 #if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
     defined(PNG_READ_PACKSWAP_SUPPORTED)
-      if (png_ptr->transformations & PNG_PACKSWAP)
+      if ((png_ptr->transformations & PNG_PACKSWAP) != 0)
          png_warning(png_ptr,
              "PNG_WRITE_PACKSWAP_SUPPORTED is not defined");
 #endif
 
 #if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
-      if (png_ptr->transformations & PNG_PACK)
+      if ((png_ptr->transformations & PNG_PACK) != 0)
          png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined");
 #endif
 
 #if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
-      if (png_ptr->transformations & PNG_SHIFT)
+      if ((png_ptr->transformations & PNG_SHIFT) != 0)
          png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined");
 #endif
 
 #if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
-      if (png_ptr->transformations & PNG_BGR)
+      if ((png_ptr->transformations & PNG_BGR) != 0)
          png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined");
 #endif
 
 #if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
-      if (png_ptr->transformations & PNG_SWAP_BYTES)
+      if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0)
          png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined");
 #endif
 
@@ -676,12 +744,13 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
    /* If interlaced and not interested in row, return */
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   if (png_ptr->interlaced != 0 &&
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
    {
       switch (png_ptr->pass)
       {
          case 0:
-            if (png_ptr->row_number & 0x07)
+            if ((png_ptr->row_number & 0x07) != 0)
             {
                png_write_finish_row(png_ptr);
                return;
@@ -689,7 +758,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
             break;
 
          case 1:
-            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+            if ((png_ptr->row_number & 0x07) != 0 || png_ptr->width < 5)
             {
                png_write_finish_row(png_ptr);
                return;
@@ -705,7 +774,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
             break;
 
          case 3:
-            if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
+            if ((png_ptr->row_number & 0x03) != 0 || png_ptr->width < 3)
             {
                png_write_finish_row(png_ptr);
                return;
@@ -721,7 +790,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
             break;
 
          case 5:
-            if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
+            if ((png_ptr->row_number & 0x01) != 0 || png_ptr->width < 2)
             {
                png_write_finish_row(png_ptr);
                return;
@@ -729,7 +798,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
             break;
 
          case 6:
-            if (!(png_ptr->row_number & 0x01))
+            if ((png_ptr->row_number & 0x01) == 0)
             {
                png_write_finish_row(png_ptr);
                return;
@@ -763,11 +832,11 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
    /* Handle interlacing */
    if (png_ptr->interlaced && png_ptr->pass < 6 &&
-       (png_ptr->transformations & PNG_INTERLACE))
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
    {
       png_do_write_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass);
       /* This should always get caught above, but still ... */
-      if (!(row_info.width))
+      if (row_info.width == 0)
       {
          png_write_finish_row(png_ptr);
          return;
@@ -777,7 +846,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
 
 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
    /* Handle other transformations */
-   if (png_ptr->transformations)
+   if (png_ptr->transformations != 0)
       png_do_write_transformations(png_ptr, &row_info);
 #endif
 
@@ -798,7 +867,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
     * 4. The filter_method is 64 and
     * 5. The color_type is RGB or RGBA
     */
-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
        (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
    {
       /* Intrapixel differencing */
@@ -851,7 +920,7 @@ png_write_flush(png_structrp png_ptr)
    png_ptr->flush_rows = 0;
    png_flush(png_ptr);
 }
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+#endif /* WRITE_FLUSH */
 
 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
 static void png_reset_filter_heuristics(png_structrp png_ptr);/* forward decl */
@@ -864,18 +933,24 @@ png_write_destroy(png_structrp png_ptr)
    png_debug(1, "in png_write_destroy");
 
    /* Free any memory zlib uses */
-   if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
+   if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
       deflateEnd(&png_ptr->zstream);
 
    /* Free our memory.  png_free checks NULL for us. */
    png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
    png_free(png_ptr, png_ptr->row_buf);
+   png_ptr->row_buf = NULL;
 #ifdef PNG_WRITE_FILTER_SUPPORTED
    png_free(png_ptr, png_ptr->prev_row);
    png_free(png_ptr, png_ptr->sub_row);
    png_free(png_ptr, png_ptr->up_row);
    png_free(png_ptr, png_ptr->avg_row);
    png_free(png_ptr, png_ptr->paeth_row);
+   png_ptr->prev_row = NULL;
+   png_ptr->sub_row = NULL;
+   png_ptr->up_row = NULL;
+   png_ptr->avg_row = NULL;
+   png_ptr->paeth_row = NULL;
 #endif
 
 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
@@ -883,10 +958,13 @@ png_write_destroy(png_structrp png_ptr)
    png_reset_filter_heuristics(png_ptr);
    png_free(png_ptr, png_ptr->filter_costs);
    png_free(png_ptr, png_ptr->inv_filter_costs);
+   png_ptr->filter_costs = NULL;
+   png_ptr->inv_filter_costs = NULL;
 #endif
 
 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
    png_free(png_ptr, png_ptr->chunk_list);
+   png_ptr->chunk_list = NULL;
 #endif
 
    /* The error handling and memory handling information is left intact at this
@@ -932,7 +1010,7 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
       return;
 
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
        (method == PNG_INTRAPIXEL_DIFFERENCING))
       method = PNG_FILTER_TYPE_BASE;
 #endif
@@ -1165,7 +1243,7 @@ png_set_filter_heuristics(png_structrp png_ptr, int heuristic_method,
    /* The internal API allocates all the arrays and ensures that the elements of
     * those arrays are set to the default value.
     */
-   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
+   if (png_init_filter_heuristics(png_ptr, heuristic_method, num_weights) == 0)
       return;
 
    /* If using the weighted method copy in the weights. */
@@ -1220,7 +1298,7 @@ png_set_filter_heuristics_fixed(png_structrp png_ptr, int heuristic_method,
    /* The internal API allocates all the arrays and ensures that the elements of
     * those arrays are set to the default value.
     */
-   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
+   if (png_init_filter_heuristics(png_ptr, heuristic_method, num_weights) == 0)
       return;
 
    /* If using the weighted method copy in the weights. */
@@ -1274,7 +1352,7 @@ png_set_filter_heuristics_fixed(png_structrp png_ptr, int heuristic_method,
    }
 }
 #endif /* FIXED_POINT */
-#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+#endif /* WRITE_WEIGHTED_FILTER */
 
 void PNGAPI
 png_set_compression_level(png_structrp png_ptr, int level)
@@ -1431,7 +1509,7 @@ png_set_text_compression_method(png_structrp png_ptr, int method)
 
    png_ptr->zlib_text_method = method;
 }
-#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
 /* end of API added to libpng-1.5.4 */
 
 void PNGAPI
@@ -1467,81 +1545,117 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
+   if ((info_ptr->valid & PNG_INFO_IDAT) == 0)
+   {
+      png_app_error(png_ptr, "no rows for png_write_image to write");
+      return;
+   }
+
    /* Write the file header information. */
    png_write_info(png_ptr, info_ptr);
 
    /* ------ these transformations don't touch the info structure ------- */
 
-#ifdef PNG_WRITE_INVERT_SUPPORTED
    /* Invert monochrome pixels */
-   if (transforms & PNG_TRANSFORM_INVERT_MONO)
+   if ((transforms & PNG_TRANSFORM_INVERT_MONO) != 0)
+#ifdef PNG_WRITE_INVERT_SUPPORTED
       png_set_invert_mono(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_INVERT_MONO not supported");
 #endif
 
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
    /* Shift the pixels up to a legal bit depth and fill in
     * as appropriate to correctly scale the image.
     */
-   if ((transforms & PNG_TRANSFORM_SHIFT)
-       && (info_ptr->valid & PNG_INFO_sBIT))
-      png_set_shift(png_ptr, &info_ptr->sig_bit);
+   if ((transforms & PNG_TRANSFORM_SHIFT) != 0)
+#ifdef PNG_WRITE_SHIFT_SUPPORTED
+      if ((info_ptr->valid & PNG_INFO_sBIT) != 0)
+         png_set_shift(png_ptr, &info_ptr->sig_bit);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_SHIFT not supported");
 #endif
 
-#ifdef PNG_WRITE_PACK_SUPPORTED
    /* Pack pixels into bytes */
-   if (transforms & PNG_TRANSFORM_PACKING)
-       png_set_packing(png_ptr);
+   if ((transforms & PNG_TRANSFORM_PACKING) != 0)
+#ifdef PNG_WRITE_PACK_SUPPORTED
+      png_set_packing(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_PACKING not supported");
 #endif
 
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
    /* Swap location of alpha bytes from ARGB to RGBA */
-   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+   if ((transforms & PNG_TRANSFORM_SWAP_ALPHA) != 0)
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
       png_set_swap_alpha(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_SWAP_ALPHA not supported");
 #endif
 
+   /* Remove a filler (X) from XRGB/RGBX/AG/GA into to convert it into
+    * RGB, note that the code expects the input color type to be G or RGB; no
+    * alpha channel.
+    */
+   if ((transforms & (PNG_TRANSFORM_STRIP_FILLER_AFTER|
+      PNG_TRANSFORM_STRIP_FILLER_BEFORE)) != 0)
+   {
 #ifdef PNG_WRITE_FILLER_SUPPORTED
-   /* Pack XRGB/RGBX/ARGB/RGBA into RGB (4 channels -> 3 channels) */
-   if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER)
-      png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
+      if ((transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER) != 0)
+      {
+         if ((transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) != 0)
+            png_app_error(png_ptr,
+               "PNG_TRANSFORM_STRIP_FILLER: BEFORE+AFTER not supported");
 
-   else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)
-      png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+         /* Continue if ignored - this is the pre-1.6.10 behavior */
+         png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
+      }
+
+      else if ((transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) != 0)
+         png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_STRIP_FILLER not supported");
 #endif
+   }
 
-#ifdef PNG_WRITE_BGR_SUPPORTED
    /* Flip BGR pixels to RGB */
-   if (transforms & PNG_TRANSFORM_BGR)
+   if ((transforms & PNG_TRANSFORM_BGR) != 0)
+#ifdef PNG_WRITE_BGR_SUPPORTED
       png_set_bgr(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_BGR not supported");
 #endif
 
-#ifdef PNG_WRITE_SWAP_SUPPORTED
    /* Swap bytes of 16-bit files to most significant byte first */
-   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+   if ((transforms & PNG_TRANSFORM_SWAP_ENDIAN) != 0)
+#ifdef PNG_WRITE_SWAP_SUPPORTED
       png_set_swap(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_SWAP_ENDIAN not supported");
 #endif
 
-#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
    /* Swap bits of 1, 2, 4 bit packed pixel formats */
-   if (transforms & PNG_TRANSFORM_PACKSWAP)
+   if ((transforms & PNG_TRANSFORM_PACKSWAP) != 0)
+#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
       png_set_packswap(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_PACKSWAP not supported");
 #endif
 
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
    /* Invert the alpha channel from opacity to transparency */
-   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+   if ((transforms & PNG_TRANSFORM_INVERT_ALPHA) != 0)
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
       png_set_invert_alpha(png_ptr);
+#else
+      png_app_error(png_ptr, "PNG_TRANSFORM_INVERT_ALPHA not supported");
 #endif
 
    /* ----------------------- end of transformations ------------------- */
 
    /* Write the bits */
-   if (info_ptr->valid & PNG_INFO_IDAT)
-       png_write_image(png_ptr, info_ptr->row_pointers);
+   png_write_image(png_ptr, info_ptr->row_pointers);
 
    /* It is REQUIRED to call this to finish writing the rest of the file */
    png_write_end(png_ptr, info_ptr);
 
-   PNG_UNUSED(transforms)   /* Quiet compiler warnings */
    PNG_UNUSED(params)
 }
 #endif
@@ -1622,16 +1736,18 @@ png_write_image_16bit(png_voidp argument)
    int aindex = 0;
    png_uint_32 y = image->height;
 
-   if (image->format & PNG_FORMAT_FLAG_ALPHA)
+   if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
    {
-      if (image->format & PNG_FORMAT_FLAG_AFIRST)
-      {
-         aindex = -1;
-         ++input_row; /* To point to the first component */
-         ++output_row;
-      }
+#     ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
+         if ((image->format & PNG_FORMAT_FLAG_AFIRST) != 0)
+         {
+            aindex = -1;
+            ++input_row; /* To point to the first component */
+            ++output_row;
+         }
 
-      else
+         else
+#     endif
          aindex = channels;
    }
 
@@ -1775,19 +1891,21 @@ png_write_image_8bit(png_voidp argument)
    png_uint_32 y = image->height;
    const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
 
-   if (image->format & PNG_FORMAT_FLAG_ALPHA)
+   if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
    {
       png_bytep row_end;
       int aindex;
 
-      if (image->format & PNG_FORMAT_FLAG_AFIRST)
-      {
-         aindex = -1;
-         ++input_row; /* To point to the first component */
-         ++output_row;
-      }
+#     ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
+         if ((image->format & PNG_FORMAT_FLAG_AFIRST) != 0)
+         {
+            aindex = -1;
+            ++input_row; /* To point to the first component */
+            ++output_row;
+         }
 
-      else
+         else
+#     endif
          aindex = channels;
 
       /* Use row_end in place of a loop counter: */
@@ -1867,7 +1985,8 @@ png_image_set_PLTE(png_image_write_control *display)
    const png_uint_32 format = image->format;
    const int channels = PNG_IMAGE_SAMPLE_CHANNELS(format);
 
-#  ifdef PNG_FORMAT_BGR_SUPPORTED
+#  if defined(PNG_FORMAT_BGR_SUPPORTED) &&\
+      defined(PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED)
       const int afirst = (format & PNG_FORMAT_FLAG_AFIRST) != 0 &&
          (format & PNG_FORMAT_FLAG_ALPHA) != 0;
 #  else
@@ -1892,13 +2011,13 @@ png_image_set_PLTE(png_image_write_control *display)
       /* This gets automatically converted to sRGB with reversal of the
        * pre-multiplication if the color-map has an alpha channel.
        */
-      if (format & PNG_FORMAT_FLAG_LINEAR)
+      if ((format & PNG_FORMAT_FLAG_LINEAR) != 0)
       {
          png_const_uint_16p entry = png_voidcast(png_const_uint_16p, cmap);
 
          entry += i * channels;
 
-         if (channels & 1) /* no alpha */
+         if ((channels & 1) != 0) /* no alpha */
          {
             if (channels >= 3) /* RGB */
             {
@@ -2025,7 +2144,7 @@ png_image_write_main(png_voidp argument)
       display->row_stride = PNG_IMAGE_ROW_STRIDE(*image);
 
    /* Set the required transforms then write the rows in the correct order. */
-   if (format & PNG_FORMAT_FLAG_COLORMAP)
+   if ((format & PNG_FORMAT_FLAG_COLORMAP) != 0)
    {
       if (display->colormap != NULL && image->colormap_entries > 0)
       {
@@ -2057,12 +2176,12 @@ png_image_write_main(png_voidp argument)
     * write an interlaced image.
     */
 
-   if (write_16bit)
+   if (write_16bit != 0)
    {
       /* The gamma here is 1.0 (linear) and the cHRM chunk matches sRGB. */
       png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_LINEAR);
 
-      if (!(image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB))
+      if ((image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB) == 0)
          png_set_cHRM_fixed(png_ptr, info_ptr,
             /* color      x       y */
             /* white */ 31270, 32900,
@@ -2072,7 +2191,7 @@ png_image_write_main(png_voidp argument)
          );
    }
 
-   else if (!(image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB))
+   else if ((image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB) == 0)
       png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_PERCEPTUAL);
 
    /* Else writing an 8-bit file and the *colors* aren't sRGB, but the 8-bit
@@ -2089,16 +2208,16 @@ png_image_write_main(png_voidp argument)
     *
     * First check for a little endian system if writing 16 bit files.
     */
-   if (write_16bit)
+   if (write_16bit != 0)
    {
       PNG_CONST png_uint_16 le = 0x0001;
 
-      if (*(png_const_bytep)&le)
+      if ((*(png_const_bytep) & le) != 0)
          png_set_swap(png_ptr);
    }
 
 #  ifdef PNG_SIMPLIFIED_WRITE_BGR_SUPPORTED
-      if (format & PNG_FORMAT_FLAG_BGR)
+      if ((format & PNG_FORMAT_FLAG_BGR) != 0)
       {
          if (!colormap && (format & PNG_FORMAT_FLAG_COLOR) != 0)
             png_set_bgr(png_ptr);
@@ -2107,7 +2226,7 @@ png_image_write_main(png_voidp argument)
 #  endif
 
 #  ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
-      if (format & PNG_FORMAT_FLAG_AFIRST)
+      if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
       {
          if (!colormap && (format & PNG_FORMAT_FLAG_ALPHA) != 0)
             png_set_swap_alpha(png_ptr);
@@ -2118,7 +2237,7 @@ png_image_write_main(png_voidp argument)
    /* If there are 16 or fewer color-map entries we wrote a lower bit depth
     * above, but the application data is still byte packed.
     */
-   if (colormap && image->colormap_entries <= 16)
+   if (colormap != 0 && image->colormap_entries <= 16)
       png_set_packing(png_ptr);
 
    /* That should have handled all (both) the transforms. */
@@ -2130,7 +2249,7 @@ png_image_write_main(png_voidp argument)
       png_const_bytep row = png_voidcast(png_const_bytep, display->buffer);
       ptrdiff_t row_bytes = display->row_stride;
 
-      if (linear)
+      if (linear != 0)
          row_bytes *= (sizeof (png_uint_16));
 
       if (row_bytes < 0)
@@ -2163,7 +2282,7 @@ png_image_write_main(png_voidp argument)
       int result;
 
       display->local_row = row;
-      if (write_16bit)
+      if (write_16bit != 0)
          result = png_safe_execute(image, png_write_image_16bit, display);
       else
          result = png_safe_execute(image, png_write_image_8bit, display);
@@ -2172,7 +2291,7 @@ png_image_write_main(png_voidp argument)
       png_free(png_ptr, row);
 
       /* Skip the 'write_end' on error: */
-      if (!result)
+      if (result == 0)
          return 0;
    }
 
@@ -2205,7 +2324,7 @@ png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
    {
       if (file != NULL)
       {
-         if (png_image_write_init(image))
+         if (png_image_write_init(image) != 0)
          {
             png_image_write_control display;
             int result;
@@ -2260,7 +2379,7 @@ png_image_write_to_file(png_imagep image, const char *file_name,
          if (fp != NULL)
          {
             if (png_image_write_to_stdio(image, fp, convert_to_8bit, buffer,
-               row_stride, colormap))
+               row_stride, colormap) != 0)
             {
                int error; /* from fflush/fclose */
 
@@ -2311,6 +2430,6 @@ png_image_write_to_file(png_imagep image, const char *file_name,
    else
       return 0;
 }
-#endif /* PNG_STDIO_SUPPORTED */
+#endif /* STDIO */
 #endif /* SIMPLIFIED_WRITE */
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */

pngwtran.c

@@ -1,8 +1,8 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.9 [February 6, 2014]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -14,90 +14,14 @@
 #include "pngpriv.h"
 
 #ifdef PNG_WRITE_SUPPORTED
-
 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
-/* Transform the data according to the user's wishes.  The order of
- * transformations is significant.
- */
-void /* PRIVATE */
-png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info)
-{
-   png_debug(1, "in png_do_write_transformations");
-
-   if (png_ptr == NULL)
-      return;
-
-#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-   if (png_ptr->transformations & PNG_USER_TRANSFORM)
-      if (png_ptr->write_user_transform_fn != NULL)
-         (*(png_ptr->write_user_transform_fn)) /* User write transform
-                                                 function */
-             (png_ptr,  /* png_ptr */
-             row_info,  /* row_info: */
-                /*  png_uint_32 width;       width of row */
-                /*  png_size_t rowbytes;     number of bytes in row */
-                /*  png_byte color_type;     color type of pixels */
-                /*  png_byte bit_depth;      bit depth of samples */
-                /*  png_byte channels;       number of channels (1-4) */
-                /*  png_byte pixel_depth;    bits per pixel (depth*channels) */
-             png_ptr->row_buf + 1);      /* start of pixel data for row */
-#endif
-
-#ifdef PNG_WRITE_FILLER_SUPPORTED
-   if (png_ptr->transformations & PNG_FILLER)
-      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
-         !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
-#endif
-
-#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_PACKSWAP)
-      png_do_packswap(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_PACK_SUPPORTED
-   if (png_ptr->transformations & PNG_PACK)
-      png_do_pack(row_info, png_ptr->row_buf + 1,
-          (png_uint_32)png_ptr->bit_depth);
-#endif
-
-#ifdef PNG_WRITE_SWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
-      png_do_swap(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
-   if (png_ptr->transformations & PNG_SHIFT)
-      png_do_shift(row_info, png_ptr->row_buf + 1,
-          &(png_ptr->shift));
-#endif
-
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_ALPHA)
-      png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_ALPHA)
-      png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_BGR_SUPPORTED
-   if (png_ptr->transformations & PNG_BGR)
-      png_do_bgr(row_info, png_ptr->row_buf + 1);
-#endif
-
-#ifdef PNG_WRITE_INVERT_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_MONO)
-      png_do_invert(row_info, png_ptr->row_buf + 1);
-#endif
-}
 
 #ifdef PNG_WRITE_PACK_SUPPORTED
 /* Pack pixels into bytes.  Pass the true bit depth in bit_depth.  The
  * row_info bit depth should be 8 (one pixel per byte).  The channels
  * should be 1 (this only happens on grayscale and paletted images).
  */
-void /* PRIVATE */
+static void
 png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
 {
    png_debug(1, "in png_do_pack");
@@ -242,7 +166,7 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
  * would pass 3 as bit_depth, and this routine would translate the
  * data to 0 to 15.
  */
-void /* PRIVATE */
+static void
 png_do_shift(png_row_infop row_info, png_bytep row,
     png_const_color_8p bit_depth)
 {
@@ -253,7 +177,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
       int shift_start[4], shift_dec[4];
       int channels = 0;
 
-      if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+      if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->red;
          shift_dec[channels] = bit_depth->red;
@@ -275,7 +199,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
          channels++;
       }
 
-      if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+      if ((row_info->color_type & PNG_COLOR_MASK_ALPHA) != 0)
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->alpha;
          shift_dec[channels] = bit_depth->alpha;
@@ -381,7 +305,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
 #endif
 
 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-void /* PRIVATE */
+static void
 png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
 {
    png_debug(1, "in png_do_write_swap_alpha");
@@ -429,7 +353,7 @@ png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = save[1];
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
 
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -468,14 +392,14 @@ png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = save[1];
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
    }
 }
 #endif
 
 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-void /* PRIVATE */
+static void
 png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
 {
    png_debug(1, "in png_do_write_invert_alpha");
@@ -525,7 +449,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
 
       else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -563,75 +487,88 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
       }
    }
 }
 #endif
-#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
 
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-/* Undoes intrapixel differencing  */
+/* Transform the data according to the user's wishes.  The order of
+ * transformations is significant.
+ */
 void /* PRIVATE */
-png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
+png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info)
 {
-   png_debug(1, "in png_do_write_intrapixel");
+   png_debug(1, "in png_do_write_transformations");
 
-   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
-   {
-      int bytes_per_pixel;
-      png_uint_32 row_width = row_info->width;
-      if (row_info->bit_depth == 8)
-      {
-         png_bytep rp;
-         png_uint_32 i;
+   if (png_ptr == NULL)
+      return;
 
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-            bytes_per_pixel = 3;
+#ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
+   if ((png_ptr->transformations & PNG_USER_TRANSFORM) != 0)
+      if (png_ptr->write_user_transform_fn != NULL)
+         (*(png_ptr->write_user_transform_fn)) /* User write transform
+                                                 function */
+             (png_ptr,  /* png_ptr */
+             row_info,  /* row_info: */
+                /*  png_uint_32 width;       width of row */
+                /*  png_size_t rowbytes;     number of bytes in row */
+                /*  png_byte color_type;     color type of pixels */
+                /*  png_byte bit_depth;      bit depth of samples */
+                /*  png_byte channels;       number of channels (1-4) */
+                /*  png_byte pixel_depth;    bits per pixel (depth*channels) */
+             png_ptr->row_buf + 1);      /* start of pixel data for row */
+#endif
 
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            bytes_per_pixel = 4;
+#ifdef PNG_WRITE_FILLER_SUPPORTED
+   if ((png_ptr->transformations & PNG_FILLER) != 0)
+      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
+         !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
+#endif
 
-         else
-            return;
+#ifdef PNG_WRITE_PACKSWAP_SUPPORTED
+   if ((png_ptr->transformations & PNG_PACKSWAP) != 0)
+      png_do_packswap(row_info, png_ptr->row_buf + 1);
+#endif
 
-         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
-         {
-            *(rp)     = (png_byte)((*rp       - *(rp + 1)) & 0xff);
-            *(rp + 2) = (png_byte)((*(rp + 2) - *(rp + 1)) & 0xff);
-         }
-      }
+#ifdef PNG_WRITE_PACK_SUPPORTED
+   if ((png_ptr->transformations & PNG_PACK) != 0)
+      png_do_pack(row_info, png_ptr->row_buf + 1,
+          (png_uint_32)png_ptr->bit_depth);
+#endif
 
-#ifdef PNG_WRITE_16BIT_SUPPORTED
-      else if (row_info->bit_depth == 16)
-      {
-         png_bytep rp;
-         png_uint_32 i;
+#ifdef PNG_WRITE_SWAP_SUPPORTED
+#  ifdef PNG_16BIT_SUPPORTED
+   if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0)
+      png_do_swap(row_info, png_ptr->row_buf + 1);
+#  endif
+#endif
 
-         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
-            bytes_per_pixel = 6;
+#ifdef PNG_WRITE_SHIFT_SUPPORTED
+   if ((png_ptr->transformations & PNG_SHIFT) != 0)
+      png_do_shift(row_info, png_ptr->row_buf + 1,
+          &(png_ptr->shift));
+#endif
 
-         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-            bytes_per_pixel = 8;
+#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
+   if ((png_ptr->transformations & PNG_SWAP_ALPHA) != 0)
+      png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1);
+#endif
 
-         else
-            return;
+#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
+   if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0)
+      png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1);
+#endif
 
-         for (i = 0, rp = row; i < row_width; i++, rp += bytes_per_pixel)
-         {
-            png_uint_32 s0   = (*(rp    ) << 8) | *(rp + 1);
-            png_uint_32 s1   = (*(rp + 2) << 8) | *(rp + 3);
-            png_uint_32 s2   = (*(rp + 4) << 8) | *(rp + 5);
-            png_uint_32 red  = (png_uint_32)((s0 - s1) & 0xffffL);
-            png_uint_32 blue = (png_uint_32)((s2 - s1) & 0xffffL);
-            *(rp    ) = (png_byte)((red >> 8) & 0xff);
-            *(rp + 1) = (png_byte)(red & 0xff);
-            *(rp + 4) = (png_byte)((blue >> 8) & 0xff);
-            *(rp + 5) = (png_byte)(blue & 0xff);
-         }
-      }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
-   }
+#ifdef PNG_WRITE_BGR_SUPPORTED
+   if ((png_ptr->transformations & PNG_BGR) != 0)
+      png_do_bgr(row_info, png_ptr->row_buf + 1);
+#endif
+
+#ifdef PNG_WRITE_INVERT_SUPPORTED
+   if ((png_ptr->transformations & PNG_INVERT_MONO) != 0)
+      png_do_invert(row_info, png_ptr->row_buf + 1);
+#endif
 }
-#endif /* PNG_MNG_FEATURES_SUPPORTED */
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE_TRANSFORMS */
+#endif /* WRITE */

pngwutil.c

@@ -2,7 +2,7 @@
 /* pngwutil.c - utilities to write a PNG file
  *
  * Last changed in libpng 1.7.0 [(PENDING RELEASE)]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
@@ -136,7 +136,7 @@ png_write_chunk_data(png_structrp png_ptr, png_const_bytep data,
       png_write_data(png_ptr, data, length);
 
       /* Update the CRC after writing the data,
-       * in case that the user I/O routine alters it.
+       * in case the user I/O routine alters it.
        */
       png_calculate_crc(png_ptr, data, length);
    }
@@ -181,7 +181,7 @@ png_write_complete_chunk(png_structrp png_ptr, png_uint_32 chunk_name,
 
    /* On 64 bit architectures 'length' may not fit in a png_uint_32. */
    if (length > PNG_UINT_31_MAX)
-      png_error(png_ptr, "length exceeds PNG maxima");
+      png_error(png_ptr, "length exceeds PNG maximum");
 
    png_write_chunk_header(png_ptr, chunk_name, (png_uint_32)length);
    png_write_chunk_data(png_ptr, data, length);
@@ -204,14 +204,14 @@ png_write_chunk(png_structrp png_ptr, png_const_bytep chunk_string,
 static png_alloc_size_t
 png_image_size(png_structrp png_ptr)
 {
-   /* Only return sizes up to the maximum of a png_uint_32, do this by limiting
+   /* Only return sizes up to the maximum of a png_uint_32; do this by limiting
     * the width and height used to 15 bits.
     */
    png_uint_32 h = png_ptr->height;
 
    if (png_ptr->rowbytes < 32768 && h < 32768)
    {
-      if (png_ptr->interlaced)
+      if (png_ptr->interlaced != 0)
       {
          /* Interlacing makes the image larger because of the replication of
           * both the filter byte and the padding to a byte boundary.
@@ -286,9 +286,7 @@ optimize_cmf(png_bytep data, png_alloc_size_t data_size)
       }
    }
 }
-#else
-#  define optimize_cmf(dp,dl) ((void)0)
-#endif /* PNG_WRITE_OPTIMIZE_CMF_SUPPORTED */
+#endif /* WRITE_OPTIMIZE_CMF */
 
 /* Initialize the compressor for the appropriate type of compression. */
 static int
@@ -297,6 +295,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
 {
    if (png_ptr->zowner != 0)
    {
+#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
       char msg[64];
 
       PNG_STRING_FROM_CHUNK(msg, owner);
@@ -308,7 +307,8 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
        * are minimal.
        */
       (void)png_safecat(msg, (sizeof msg), 10, " using zstream");
-#     if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
+#endif
+#if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
          png_warning(png_ptr, msg);
 
          /* Attempt sane error recovery */
@@ -319,9 +319,9 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
          }
 
          png_ptr->zowner = 0;
-#     else
+#else
          png_error(png_ptr, msg);
-#     endif
+#endif
    }
 
    {
@@ -334,7 +334,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
 
       if (owner == png_IDAT)
       {
-         if (png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY)
+         if ((png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY) != 0)
             strategy = png_ptr->zlib_strategy;
 
          else if (png_ptr->do_filter != PNG_FILTER_NONE)
@@ -346,20 +346,20 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
 
       else
       {
-#        ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
             level = png_ptr->zlib_text_level;
             method = png_ptr->zlib_text_method;
             windowBits = png_ptr->zlib_text_window_bits;
             memLevel = png_ptr->zlib_text_mem_level;
             strategy = png_ptr->zlib_text_strategy;
-#        else
+#else
             /* If customization is not supported the values all come from the
              * IDAT values except for the strategy, which is fixed to the
              * default.  (This is the pre-1.6.0 behavior too, although it was
              * implemented in a very different way.)
              */
             strategy = Z_DEFAULT_STRATEGY;
-#        endif
+#endif
       }
 
       /* Adjust 'windowBits' down if larger than 'data_size'; to stop this
@@ -386,7 +386,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
       }
 
       /* Check against the previous initialized values, if any. */
-      if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) &&
+      if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0 &&
          (png_ptr->zlib_set_level != level ||
          png_ptr->zlib_set_method != method ||
          png_ptr->zlib_set_window_bits != windowBits ||
@@ -410,7 +410,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
       /* Now initialize if required, setting the new parameters, otherwise just
        * to a simple reset to the previous parameters.
        */
-      if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
+      if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
          ret = deflateReset(&png_ptr->zstream);
 
       else
@@ -492,7 +492,7 @@ png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
    int ret;
 
    /* To find the length of the output it is necessary to first compress the
-    * input, the result is buffered rather than using the two-pass algorithm
+    * input. The result is buffered rather than using the two-pass algorithm
     * that is used on the inflate side; deflate is assumed to be slower and a
     * PNG writer is assumed to have more memory available than a PNG reader.
     *
@@ -589,7 +589,7 @@ png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
       }
       while (ret == Z_OK);
 
-      /* There may be some space left in the last output buffer, this needs to
+      /* There may be some space left in the last output buffer. This needs to
        * be subtracted from output_len.
        */
       output_len -= png_ptr->zstream.avail_out;
@@ -612,14 +612,15 @@ png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
       /* Reset zlib for another zTXt/iTXt or image data */
       png_ptr->zowner = 0;
 
-      /* The only success case is Z_STREAM_END, input_len must be 0, if not this
+      /* The only success case is Z_STREAM_END, input_len must be 0; if not this
        * is an internal error.
        */
       if (ret == Z_STREAM_END && input_len == 0)
       {
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
          /* Fix up the deflate header, if required */
          optimize_cmf(comp->output, comp->input_len);
-
+#endif
          /* But Z_OK is returned, not Z_STREAM_END; this allows the claim
           * function above to return Z_STREAM_END on an error (though it never
           * does in the current versions of zlib.)
@@ -662,7 +663,7 @@ png_write_compressed_data_out(png_structrp png_ptr, compression_state *comp)
    if (output_len > 0)
       png_error(png_ptr, "error writing ancillary chunked compressed data");
 }
-#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
+#endif /* WRITE_COMPRESSED_TEXT */
 
 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
     defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
@@ -699,7 +700,7 @@ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
       if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/))
          *new_key++ = ch, ++key_len, space = 0;
 
-      else if (!space)
+      else if (space == 0)
       {
          /* A space or an invalid character when one wasn't seen immediately
           * before; output just a space.
@@ -711,14 +712,14 @@ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
             bad_character = ch;
       }
 
-      else if (!bad_character)
+      else if (bad_character == 0)
          bad_character = ch; /* just skip it, record the first error */
    }
 
-   if (key_len > 0 && space) /* trailing space */
+   if (key_len > 0 && space != 0) /* trailing space */
    {
       --key_len, --new_key;
-      if (!bad_character)
+      if (bad_character == 0)
          bad_character = 32;
    }
 
@@ -728,11 +729,12 @@ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
    if (key_len == 0)
       return 0;
 
+#ifdef PNG_WARNINGS_SUPPORTED
    /* Try to only output one warning per keyword: */
-   if (*key) /* keyword too long */
+   if (*key != 0) /* keyword too long */
       png_warning(png_ptr, "keyword truncated");
 
-   else if (bad_character)
+   else if (bad_character != 0)
    {
       PNG_WARNING_PARAMETERS(p)
 
@@ -741,6 +743,7 @@ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
 
       png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'");
    }
+#endif /* WARNINGS */
 
    return key_len;
 }
@@ -845,8 +848,8 @@ png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
     */
    if (
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-       !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
-       ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+       !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
+       ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) &&
        (color_type == PNG_COLOR_TYPE_RGB ||
         color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
        (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
@@ -898,7 +901,7 @@ png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
    /* Write the chunk */
    png_write_complete_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
 
-   if (!(png_ptr->do_filter))
+   if ((png_ptr->do_filter) == PNG_NO_FILTERS)
    {
       if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
           png_ptr->bit_depth < 8)
@@ -927,7 +930,7 @@ png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
 
    if ((
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-       !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) &&
+       (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 &&
 #endif
        num_pal == 0) || num_pal > 256)
    {
@@ -943,7 +946,7 @@ png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
       }
    }
 
-   if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
+   if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) == 0)
    {
       png_warning(png_ptr,
           "Ignoring request to write a PLTE chunk in grayscale PNG");
@@ -998,7 +1001,7 @@ png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
  * Z_FINISH: this is the end of the input, do a Z_FINISH and clean up
  *
  * The routine manages the acquire and release of the png_ptr->zstream by
- * checking and (at the end) clearing png_ptr->zowner, it does some sanity
+ * checking and (at the end) clearing png_ptr->zowner; it does some sanity
  * checks on the 'mode' flags while doing this.
  */
 void /* PRIVATE */
@@ -1058,7 +1061,7 @@ png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
       input_len += png_ptr->zstream.avail_in;
       png_ptr->zstream.avail_in = 0;
 
-      /* OUTPUT: write complete IDAT chunks when avail_out drops to zero, note
+      /* OUTPUT: write complete IDAT chunks when avail_out drops to zero. Note
        * that these two zstream fields are preserved across the calls, therefore
        * there is no need to set these up on entry to the loop.
        */
@@ -1070,11 +1073,11 @@ png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
          /* Write an IDAT containing the data then reset the buffer.  The
           * first IDAT may need deflate header optimization.
           */
-#        ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-            if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
-               png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
+            if ((png_ptr->mode & PNG_HAVE_IDAT) == 0 &&
+                png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
                optimize_cmf(data, png_image_size(png_ptr));
-#        endif
+#endif
 
          png_write_complete_chunk(png_ptr, png_IDAT, data, size);
          png_ptr->mode |= PNG_HAVE_IDAT;
@@ -1090,7 +1093,7 @@ png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
             continue;
       }
 
-      /* The order of these checks doesn't matter much; it just effect which
+      /* The order of these checks doesn't matter much; it just affects which
        * possible error might be detected if multiple things go wrong at once.
        */
       if (ret == Z_OK) /* most likely return code! */
@@ -1116,11 +1119,11 @@ png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
          png_bytep data = png_ptr->zbuffer_list->output;
          uInt size = png_ptr->zbuffer_size - png_ptr->zstream.avail_out;
 
-#        ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-            if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
-               png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
-               optimize_cmf(data, png_image_size(png_ptr));
-#        endif
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
+         if ((png_ptr->mode & PNG_HAVE_IDAT) == 0 &&
+             png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+            optimize_cmf(data, png_image_size(png_ptr));
+#endif
 
          png_write_complete_chunk(png_ptr, png_IDAT, data, size);
          png_ptr->zstream.avail_out = 0;
@@ -1339,7 +1342,7 @@ png_write_sBIT(png_structrp png_ptr, png_const_color_8p sbit, int color_type)
    png_debug(1, "in png_write_sBIT");
 
    /* Make sure we don't depend upon the order of PNG_COLOR_8 */
-   if (color_type & PNG_COLOR_MASK_COLOR)
+   if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
    {
       png_byte maxbits;
 
@@ -1372,7 +1375,7 @@ png_write_sBIT(png_structrp png_ptr, png_const_color_8p sbit, int color_type)
       size = 1;
    }
 
-   if (color_type & PNG_COLOR_MASK_ALPHA)
+   if ((color_type & PNG_COLOR_MASK_ALPHA) != 0)
    {
       if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
       {
@@ -1461,9 +1464,9 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
       png_save_uint_16(buf + 2, tran->green);
       png_save_uint_16(buf + 4, tran->blue);
 #ifdef PNG_WRITE_16BIT_SUPPORTED
-      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]) != 0)
 #else
-      if (buf[0] | buf[2] | buf[4])
+      if ((buf[0] | buf[2] | buf[4]) != 0)
 #endif
       {
          /* Also checked in png_set_tRNS */
@@ -1496,8 +1499,8 @@ png_write_bKGD(png_structrp png_ptr, png_const_color_16p back, int color_type)
    {
       if (
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-          (png_ptr->num_palette ||
-          (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) &&
+          (png_ptr->num_palette != 0 ||
+          (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0) &&
 #endif
          back->index >= png_ptr->num_palette)
       {
@@ -1509,15 +1512,15 @@ png_write_bKGD(png_structrp png_ptr, png_const_color_16p back, int color_type)
       png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
    }
 
-   else if (color_type & PNG_COLOR_MASK_COLOR)
+   else if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
    {
       png_save_uint_16(buf, back->red);
       png_save_uint_16(buf + 2, back->green);
       png_save_uint_16(buf + 4, back->blue);
 #ifdef PNG_WRITE_16BIT_SUPPORTED
-      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]) != 0)
 #else
-      if (buf[0] | buf[2] | buf[4])
+      if ((buf[0] | buf[2] | buf[4]) != 0)
 #endif
       {
          png_warning(png_ptr,
@@ -1612,7 +1615,7 @@ png_write_tEXt(png_structrp png_ptr, png_const_charp key, png_const_charp text,
     */
    png_write_chunk_data(png_ptr, new_key, key_len + 1);
 
-   if (text_len)
+   if (text_len != 0)
       png_write_chunk_data(png_ptr, (png_const_bytep)text, text_len);
 
    png_write_chunk_end(png_ptr);
@@ -1623,14 +1626,13 @@ png_write_tEXt(png_structrp png_ptr, png_const_charp key, png_const_charp text,
 /* Write a compressed text chunk */
 void /* PRIVATE */
 png_write_zTXt(png_structrp png_ptr, png_const_charp key, png_const_charp text,
-    png_size_t text_len, int compression)
+    int compression)
 {
    png_uint_32 key_len;
    png_byte new_key[81];
    compression_state comp;
 
    png_debug(1, "in png_write_zTXt");
-   PNG_UNUSED(text_len) /* Always use strlen */
 
    if (compression == PNG_TEXT_COMPRESSION_NONE)
    {
@@ -1738,7 +1740,7 @@ png_write_iTXt(png_structrp png_ptr, int compression, png_const_charp key,
 
    png_text_compress_init(&comp, (png_const_bytep)text, strlen(text));
 
-   if (compression)
+   if (compression != 0)
    {
       if (png_text_compress(png_ptr, png_iTXt, &comp, prefix_len) != Z_OK)
          png_error(png_ptr, png_ptr->zstream.msg);
@@ -1761,7 +1763,7 @@ png_write_iTXt(png_structrp png_ptr, int compression, png_const_charp key,
 
    png_write_chunk_data(png_ptr, (png_const_bytep)lang_key, lang_key_len);
 
-   if (compression)
+   if (compression != 0)
       png_write_compressed_data_out(png_ptr, &comp);
 
    else
@@ -1977,7 +1979,7 @@ png_write_alloc_filter_row_buffers(png_structrp png_ptr, int filters)
       png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
    }
 }
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
 
 /* Initializes the row writing capability of libpng */
 void /* PRIVATE */
@@ -2038,7 +2040,7 @@ png_write_start_row(png_structrp png_ptr)
    /* We only need to keep the previous row if we are using one of the following
     * filters.
     */
-   if (filters & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
+   if ((filters & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) != 0)
       png_ptr->prev_row = png_voidcast(png_bytep, png_calloc(png_ptr,
          buf_size));
 
@@ -2047,13 +2049,13 @@ png_write_start_row(png_structrp png_ptr)
    png_ptr->do_filter = (png_byte)filters; /* in case it was changed above */
 #else
    png_ptr->do_filter = PNG_FILTER_NONE;
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
    /* If interlaced, we need to set up width and height of pass */
-   if (png_ptr->interlaced)
+   if (png_ptr->interlaced != 0)
    {
-      if (!(png_ptr->transformations & PNG_INTERLACE))
+      if ((png_ptr->transformations & PNG_INTERLACE) == 0)
       {
          png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
              png_pass_ystart[0]) / png_pass_yinc[0];
@@ -2108,10 +2110,10 @@ png_write_finish_row(png_structrp png_ptr)
 
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
    /* If interlaced, go to next pass */
-   if (png_ptr->interlaced)
+   if (png_ptr->interlaced != 0)
    {
       png_ptr->row_number = 0;
-      if (png_ptr->transformations & PNG_INTERLACE)
+      if ((png_ptr->transformations & PNG_INTERLACE) != 0)
       {
          png_ptr->pass++;
       }
@@ -2136,7 +2138,7 @@ png_write_finish_row(png_structrp png_ptr)
                 png_pass_ystart[png_ptr->pass]) /
                 png_pass_yinc[png_ptr->pass];
 
-            if (png_ptr->transformations & PNG_INTERLACE)
+            if ((png_ptr->transformations & PNG_INTERLACE) != 0)
                break;
 
          } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
@@ -2414,7 +2416,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
    /* We don't need to test the 'no filter' case if this is the only filter
     * that has been chosen, as it doesn't actually do anything to the data.
     */
-   if ((filter_to_do & PNG_FILTER_NONE) && filter_to_do != PNG_FILTER_NONE)
+   if ((filter_to_do & PNG_FILTER_NONE) != 0 && filter_to_do != PNG_FILTER_NONE)
    {
       png_bytep rp;
       png_uint_32 sum = 0;
@@ -2490,7 +2492,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
       best_row = png_ptr->sub_row;
    }
 
-   else if (filter_to_do & PNG_FILTER_SUB)
+   else if ((filter_to_do & PNG_FILTER_SUB) != 0)
    {
       png_bytep rp, dp, lp;
       png_uint_32 sum = 0, lmins = mins;
@@ -2611,7 +2613,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
       best_row = png_ptr->up_row;
    }
 
-   else if (filter_to_do & PNG_FILTER_UP)
+   else if ((filter_to_do & PNG_FILTER_UP) != 0)
    {
       png_bytep rp, dp, pp;
       png_uint_32 sum = 0, lmins = mins;
@@ -2725,7 +2727,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
       best_row = png_ptr->avg_row;
    }
 
-   else if (filter_to_do & PNG_FILTER_AVG)
+   else if ((filter_to_do & PNG_FILTER_AVG) != 0)
    {
       png_bytep rp, dp, pp, lp;
       png_uint_32 sum = 0, lmins = mins;
@@ -2827,7 +2829,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
    }
 
    /* Paeth filter */
-   if (filter_to_do == PNG_FILTER_PAETH)
+   if ((filter_to_do == PNG_FILTER_PAETH) != 0)
    {
       png_bytep rp, dp, pp, cp, lp;
       png_size_t i;
@@ -2866,7 +2868,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
       best_row = png_ptr->paeth_row;
    }
 
-   else if (filter_to_do & PNG_FILTER_PAETH)
+   else if ((filter_to_do & PNG_FILTER_PAETH) != 0)
    {
       png_bytep rp, dp, pp, cp, lp;
       png_uint_32 sum = 0, lmins = mins;
@@ -2950,7 +2952,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
 
          else
             p = c;
-#endif /* PNG_SLOW_PAETH */
+#endif /* SLOW_PAETH */
 
          v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
 
@@ -2999,7 +3001,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
          best_row = png_ptr->paeth_row;
       }
    }
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
 
    /* Do the actual writing of the filtered row data from the chosen filter. */
    png_write_filtered_row(png_ptr, best_row, row_info->rowbytes+1);
@@ -3019,7 +3021,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
       png_ptr->prev_filters[j] = best_row[0];
    }
 #endif
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
 }
 
 
@@ -3044,7 +3046,7 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
       png_ptr->prev_row = png_ptr->row_buf;
       png_ptr->row_buf = tptr;
    }
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
 
    /* Finish row - updates counters and flushes zlib if last row */
    png_write_finish_row(png_ptr);
@@ -3059,4 +3061,4 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
    }
 #endif
 }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */

projects/vstudio/readme.txt

@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.7.0beta08 - April 14, 2013
+libpng version 1.7.0beta41 - November 7, 2014
 
 Copyright (c) 1998-2010 Glenn Randers-Pehrson
 

projects/vstudio/zlib.props

@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.7.0beta08 - April 14, 2013
+ * libpng version 1.7.0beta41 - November 7, 2014
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *
@@ -24,7 +24,7 @@
 	 source.
 
 	 If you use a relative directory name (as below) then it must be
-	 relative to the project directories; these are one level deepers than
+	 relative to the project directories; these are one level deeper than
 	 the directories containing this file.
 
 	 If the version of zlib you use does not match that used when the
@@ -32,7 +32,7 @@
 	 versions do not match.  The zlib version used in this build is recorded
 	 below:
      -->
-    <ZLibSrcDir>..\..\..\..\zlib-1.2.5</ZLibSrcDir>
+    <ZLibSrcDir>..\..\..\..\zlib-1.2.8</ZLibSrcDir>
 
     <!-- The following line allows compilation for an ARM target with Visual
          Studio 2012.  Notice that this is not supported by the Visual Studio

scripts/README.txt

@@ -1,9 +1,9 @@
 
-Makefiles for  libpng version 1.7.0beta08 - April 14, 2013
+Makefiles for  libpng version 1.7.0beta41 - November 7, 2014
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng17.so.17.1.7.0beta08)
+                       (gcc, creates libpng17.so.17.1.7.0beta41)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
                        ansi2knr (Requires ansi2knr.c from
@@ -19,8 +19,6 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.darwin   =>  Darwin makefile, can use on MacosX
  makefile.dec      =>  DEC Alpha UNIX makefile
  makefile.dj2      =>  DJGPP 2 makefile
- makefile.elf      =>  Linux/ELF makefile symbol versioning,
-                       (gcc, creates libpng17.so.17.1.7.0beta08)
  makefile.freebsd  =>  FreeBSD makefile
  makefile.gcc      =>  Generic gcc makefile
  makefile.hpgcc    =>  HPUX makefile using gcc
@@ -35,12 +33,12 @@ pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.os2      =>  OS/2 Makefile (gcc and emx, requires libpng.def)
  makefile.sco      =>  For SCO OSr5  ELF and Unixware 7 with Native cc
  makefile.sggcc    =>  Silicon Graphics (gcc,
-                       creates libpng17.so.17.1.7.0beta08)
+                       creates libpng17.so.17.1.7.0beta41)
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
  makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng17.so.17.1.7.0beta08)
+                       creates libpng17.so.17.1.7.0beta41)
  makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng17.so.17.1.7.0beta08)
+                       creates libpng17.so.17.1.7.0beta41)
  makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
  makefile.sunos    =>  Sun makefile
  makefile.32sunu   =>  Sun Ultra 32-bit makefile

scripts/def.dfn

@@ -21,7 +21,7 @@ PNG_DFN "OS2 DESCRIPTION "PNG image compression library""
 PNG_DFN "OS2 CODE PRELOAD MOVEABLE DISCARDABLE"
 PNG_DFN ""
 PNG_DFN "EXPORTS"
-PNG_DFN ";Version 1.7.0beta08"
+PNG_DFN ";Version 1.7.0beta41"
 
 #define PNG_EXPORTA(ordinal, type, name, args, attributes)\
         PNG_DFN "@" SYMBOL_PREFIX "@@" name "@"

scripts/descrip.mms

@@ -33,20 +33,20 @@ clean :
 
 
 # Other dependencies.
-png.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngpread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngset.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngget.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngrtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngrutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngerror.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngmem.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngrio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngwio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngtrans.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngwrite.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngwtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
-pngwutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h,             pnginfo.h, pngdebug.h
+png.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngpread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngset.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngget.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngread.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngrtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngrutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngerror.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngmem.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngrio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngwio.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngtrans.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngwrite.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngwtran.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
+pngwutil.obj : png.h, pngconf.h, pnglibconf.h, pngpriv.h, pngstruct.h, pnginfo.h, pngdebug.h
 
-pngtest.obj : png.h, pngconf.h
+pngtest.obj : png.h, pngconf.h, pnglibconf.h

scripts/dfn.awk

@@ -1,9 +1,9 @@
 #!/bin/awk -f
 # scripts/dfn.awk - process a .dfn file
 #
-# last changed in libpng version 1.5.14 - February 4, 2013
+# last changed in libpng version 1.5.19 - August 21, 2014
 #
-# Copyright (c) 2013-2013 Glenn Randers-Pehrson
+# Copyright (c) 2013-2014 Glenn Randers-Pehrson
 #
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -25,7 +25,7 @@ BEGIN{
 # The output file must be specified before any input:
 NR==1 && out == "/dev/null" {
    print "out=output.file must be given on the command line"
-   # but continue without setting the error code, this allows the
+   # but continue without setting the error code; this allows the
    # script to be checked easily
 }
 
@@ -61,14 +61,14 @@ $1 ~ /^PNG_DFN_END_SORT/{
 }
 
 /^[^"]*PNG_DFN *".*"[^"]*$/{
-   # A definition line, apparently correctly formated, extract the
+   # A definition line, apparently correctly formatted; extract the
    # definition then replace any doubled "" that remain with a single
    # double quote.  Notice that the original doubled double quotes
    # may have been split by tokenization
    #
-   # Sometimes GCC splits the PNG_DFN lines, we know this has happened
+   # Sometimes GCC splits the PNG_DFN lines; we know this has happened
    # if the quotes aren't closed and must read another line.  In this
-   # case it is essential to reject lines that start '#' because those
+   # case it is essential to reject lines that start with '#' because those
    # are introduced #line directives.
    orig=$0
    line=$0
@@ -126,13 +126,13 @@ $1 ~ /^PNG_DFN_END_SORT/{
          else while (1) {
             if (getline nextline) {
                # If the line starts with '#' it is a preprocesor line directive
-               # from cc -E, skip it:
+               # from cc -E; skip it:
                if (nextline !~ /^#/) {
                   line = line " " nextline
                   break
                }
             } else {
-               # This is end-of-input - probably a missig "@ on the first line:
+               # This is end-of-input - probably a missing "@ on the first line:
                print "line", lineno ": unbalanced @\" ... \"@ pair"
                err=1
                next
@@ -144,7 +144,7 @@ $1 ~ /^PNG_DFN_END_SORT/{
       }
 
       # Attempt to remove a trailing " (not preceded by '@') - if this can
-      # be done stop now, if not assume a split line again
+      # be done, stop now; if not assume a split line again
       if (sub(/"[^"]*$/, "", line))
          break
 
@@ -189,7 +189,7 @@ $1 ~ /^PNG_DFN_END_SORT/{
    next
 }
 
-/PNG_DFN/{
+/PNG_DFN/{
    print "line", NR, "incorrectly formatted PNG_DFN line:"
    print $0
    err = 1

scripts/intprefix.dfn

@@ -15,5 +15,8 @@
 #define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
         PNG_DFN "@" name "@"
 
+#define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
+        PNG_DFN "@" name "@"
+
 #define PNGPREFIX_H /* self generation */
 #include "../pngpriv.h"

scripts/libpng-config-head.in

@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.7.0beta08
+version=1.7.0beta41
 prefix=""
 libdir=""
 libs=""