[libpng16] Imported from libpng-1.6.24beta05.tar

only one filter is a candidate for selection. This trades off code size (added
png_setup_*_row_only() functions) for speed.

ANNOUNCE

@@ -1,4 +1,4 @@
-Libpng 1.6.22rc01 - May 14, 2016
+Libpng 1.6.24beta05 - July 13, 2016
 
 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.
@@ -8,99 +8,82 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script
 
-   1.6.22rc01.tar.xz (LZMA-compressed, recommended)
-   1.6.22rc01.tar.gz
+   1.6.24beta05.tar.xz (LZMA-compressed, recommended)
+   1.6.24beta05.tar.gz
 
 Source files with CRLF line endings (for Windows), without the
 "configure" script
 
-   lp1622r01.7z  (LZMA-compressed, recommended)
-   lp1622r01.zip
+   lp1624b05.7z  (LZMA-compressed, recommended)
+   lp1624b05.zip
 
 Other information:
 
-   1.6.22rc01-README.txt
-   1.6.22rc01-LICENSE.txt
-   libpng-1.6.22rc01-*.asc (armored detached GPG signatures)
+   1.6.24beta05-README.txt
+   1.6.24beta05-LICENSE.txt
+   libpng-1.6.24beta05-*.asc (armored detached GPG signatures)
 
-Changes since the last public release (1.6.21):
+Changes since the last public release (1.6.23):
 
-Version 1.6.22beta01 [January 23, 2016]
-  Changed PNG_USE_MKSTEMP to __COVERITY__ to select alternate
-    "tmpfile()" implementation in contrib/libtests/pngstest.c
-  Fixed NO_STDIO build of pngunknown.c to skip calling png_init_io()
-    if there is no stdio.h support.
-  Added a png_image_write_to_memory() API and a number of assist macros
-    to allow an application that uses the simplified API write to bypass
-    stdio and write directly to memory.
-  Added some warnings (png.h) and some check code to detect *possible*
-    overflow in the ROW_STRIDE and simplified image SIZE macros.  This
-    disallows image width/height/format that *might* overflow.  This is
-    a quiet API change that limits in-memory image size (uncompressed) to
-    less than 4GByte and image row size (stride) to less than 2GByte.
-  Revised workaround for false-positive Coverity issue in pngvalid.c.
+Version 1.6.24beta01 [June 11, 2016]
+  Avoid potential overflow of the PNG_IMAGE_SIZE macro.  This macro
+    is not used within libpng, but is used in some of the examples.
 
-Version 1.6.22beta02 [February 8, 2016]
-  Only use exit(77) in configure builds.
-  Corrected error in PNG_IMAGE_PNG_SIZE_MAX. This new macro underreported
-    the palette size because it failed to take into account that the memory
-    palette has to be expanded to full RGB when it is written to PNG.
-  Updated CMakeLists.txt, added supporting scripts/gen*.cmake.in
-    and test.cmake.in (Roger Leigh).
-  Relaxed limit checks on gamma values in pngrtran.c. As suggested in
-    the comments gamma values outside the range currently permitted
-    by png_set_alpha_mode are useful for HDR data encoding.  These values
-    are already permitted by png_set_gamma so it is reasonable caution to
-    extend the png_set_alpha_mode range as HDR imaging systems are starting
-    to emerge.
+Version 1.6.24beta02 [June 23, 2016]
+  Correct filter heuristic overflow handling. This was broken when the
+    write filter code was moved out-of-line; if there is a single filter and
+    the heuristic sum overflows the calculation of the filtered line is not
+    completed.  In versions prior to 1.6 the code was duplicated in-line
+    and the check not performed, so the filter operation completed; however,
+    in the multi-filter case where the sum is performed the 'none' filter would
+    be selected if all the sums overflowed, even if it wasn't in the filter
+    list.  The fix to the first problem is simply to provide PNG_SIZE_MAX as
+    the current lmins sum value; this means the sum can never exceed it and
+    overflows silently.  A reasonable compiler that does choose to inline
+    the code will simply eliminate the sum check.
+  The fix to the second problem is to use high precision arithmetic (this is
+    implemented in 1.7), however a simple safe fix here is to chose the lowest
+    numbered filter in the list from png_set_filter (this only works if the
+    first problem is also fixed) (John Bowler).
+  Use a more efficient absolute value calculation on SSE2 (Matthieu Darbois).
+  Fixed the case where PNG_IMAGE_BUFFER_SIZE can overflow in the application
+    as a result of the application using an increased 'row_stride'; previously
+    png_image_finish_read only checked for overflow on the base calculation of
+    components.  (I.e. it checked for overflow of a 32-bit number on the total
+    number of pixel components in the output format, not the possibly padded row
+    length and not the number of bytes, which for linear formats is twice the
+    number of components.)
+  MSVC does not like '-(unsigned)', so replaced it with 0U-(unsigned)
+  MSVC does not like (uInt) = -(unsigned) (i.e. as an initializer), unless
+    the conversion is explicitly invoked by a cast.
+  Put the SKIP definition in the correct place. It needs to come after the
+    png.h include (see all the other .c files in contrib/libtests) because it
+    depends on PNG_LIBPNG_VER.
+  Removed the three compile warning options from the individual project
+    files into the zlib.props globals.  It increases the warning level from 4
+    to All and adds a list of the warnings that need to be turned off.  This is
+    semi-documentary; the intent is to tell libpng users which warnings have
+    been examined and judged non-fixable at present.  The warning about
+    structure padding is fixable, but it would be a signficant change (moving
+    structure members around).
 
-Version 1.6.22beta03 [March 9, 2016]
-  Added a common-law trademark notice and export control information
-    to the LICENSE file, png.h, and the man page.
-  Restored "& 0xff" in png_save_uint_16() and png_save_uint_32() that
-    were accidentally removed from libpng-1.6.17. 
-  Changed PNG_INFO_cHNK and PNG_FREE_cHNK from 0xnnnn to 0xnnnnU in png.h
-    (Robert C. Seacord).
-  Removed dubious "#if INT_MAX" test from png.h that was added to
-    libpng-1.6.19beta02 (John Bowler).
-  Add ${INCLUDES} in scripts/genout.cmake.in (Bug report by Nixon Kwok).
-  Updated LICENSE to say files in the contrib directory are not
-    necessarily under the libpng license, and that some makefiles have
-    other copyright owners.
-  Added INTEL-SSE2 support (Mike Klein and Matt Sarett, Google, Inc.).
-  Made contrib/libtests/timepng more robust.  The code no longer gives
-    up/fails on invalid PNG data, it just skips it (with error messages).
-    The code no longer fails on PNG files with data beyond IEND.  Options
-    exist to use png_read_png (reading the whole image, not by row) and, in
-    that case, to apply any of the supported transforms.  This makes for
-    more realistic testing; the decoded data actually gets used in a
-    meaningful fashion (John Bowler).
-  Fixed some misleading indentation (Krishnaraj Bhat).
+Version 1.6.24beta03 [July 4, 2016]
+  Optimized absolute value calculation in filter selection, similar to
+    code in the PAETH decoder in pngrutil.c. Build with PNG_USE_ABS to
+    use this.
+  Added pngcp to the build together with a pngcp.dfa configuration test.
+  Added high resolution timing to pngcp.
+  Added "Common linking failures" section to INSTALL.
+  Relocated misplaced #endif in png.c sRGB profile checking.
+  Fixed two Coverity issues in pngcp.c.
 
-Version 1.6.22beta04 [April 5, 2016]
-  Force GCC compilation to C89 if needed (Dagobert Michelsen).
-  SSE filter speed improvements for bpp=3:
-    memcpy-free implementations of load3() / store3().
-    call load3() only when needed at the end of a scanline.
+Version 1.6.24beta04 [July 8, 2016]
+  Avoid filter-selection heuristic sum calculations in cases where only one
+    filter is a candidate for selection. This trades off code size (added
+    private png_setup_*_row_only() functions) for speed.
 
-Version 1.6.22beta05 [April 27, 2016]
-  Added PNG_FAST_FILTERS macro (defined as
-    PNG_FILTER_NONE|PNG_FILTER_SUB|PNG_FILTER_UP).
-  Various fixes for contrib/libtests/timepng.c
-  Moved INTEL-SSE code from pngpriv.h into contrib/intel/intel_sse.patch.
-  Fixed typo (missing underscore) in #define PNG_READ_16_TO_8_SUPPORTED
-    (Bug report by Y.Ohashik).
-
-Version 1.6.22beta06 [May 5, 2016]
-  Rebased contrib/intel_sse.patch.
-  Quieted two Coverity issues in contrib/libtests/timepng.c.
-  Fixed issues with scripts/genout.cmake.in (David Capello, Nixon Kwok):
-    Added support to use multiple directories in ZLIBINCDIR variable,
-    Fixed CMAKE_C_FLAGS with multiple values when genout is compiled on MSVC,
-    Fixed pnglibconf.c compilation on OS X including the sysroot path.
-
-Version 1.6.22rcp1 [May 14, 2016]
-  No changes.
+Version 1.6.24beta05 [July 13, 2016]
+  Fixed some indentation to comply with our coding style.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit

CHANGES

@@ -5562,6 +5562,100 @@ Version 1.6.22beta06 [May 5, 2016]
 Version 1.6.22rc01 [May 14, 2016]
   No changes.
 
+Version 1.6.22rc02 [May 16, 2016]
+  Removed contrib/timepng from default build; it does not build on platforms
+    that don't supply clock_gettime().
+
+Version 1.6.22rc03 [May 17, 2016]
+  Restored contrib/timepng to default build but check for the presence
+    of clock_gettime() in configure.ac and Makefile.am.
+
+Version 1.6.22 [May 26, 2016]
+  No changes.
+
+Version 1.6.23beta01 [May 29, 2016]
+  Stop a potential memory leak in png_set_tRNS() (Bug report by Ted Ying).
+  Fixed the progressive reader to handle empty first IDAT chunk properly
+    (patch by Timothy Nikkel).  This bug was introduced in libpng-1.6.0 and
+    only affected the libpng16 branch.
+  Added tests in pngvalid.c to check zero-length IDAT chunks in various
+    positions.  Fixed the sequential reader to handle these more robustly
+    (John Bowler).
+
+Version 1.6.23rc01 [June 2, 2016]
+  Corrected progressive read input buffer in pngvalid.c. The previous version
+    the code invariably passed just one byte at a time to libpng.  The intent
+    was to pass a random number of bytes in the range 0..511.
+  Moved sse2 prototype from pngpriv.h to contrib/intel/intel_sse.patch.
+  Added missing ")" in pngerror.c (Matt Sarrett).
+
+Version 1.6.23rc02 [June 4, 2016]
+  Fixed undefined behavior in png_push_save_buffer(). Do not call
+    memcpy() with a null source, even if count is zero (Leon Scroggins III).
+
+Version 1.6.23 [June 9, 2016]
+  Fixed bad link to RFC2083 in png.5 (Nikola Forro).
+
+Version 1.6.24beta01 [June 11, 2016]
+  Avoid potential overflow of the PNG_IMAGE_SIZE macro.  This macro
+    is not used within libpng, but is used in some of the examples.
+
+Version 1.6.24beta02 [June 23, 2016]
+  Correct filter heuristic overflow handling. This was broken when the
+    write filter code was moved out-of-line; if there is a single filter and
+    the heuristic sum overflows the calculation of the filtered line is not
+    completed.  In versions prior to 1.6 the code was duplicated in-line
+    and the check not performed, so the filter operation completed; however,
+    in the multi-filter case where the sum is performed the 'none' filter would
+    be selected if all the sums overflowed, even if it wasn't in the filter
+    list.  The fix to the first problem is simply to provide PNG_SIZE_MAX as
+    the current lmins sum value; this means the sum can never exceed it and
+    overflows silently.  A reasonable compiler that does choose to inline
+    the code will simply eliminate the sum check.
+  The fix to the second problem is to use high precision arithmetic (this is
+    implemented in 1.7), however a simple safe fix here is to chose the lowest
+    numbered filter in the list from png_set_filter (this only works if the
+    first problem is also fixed) (John Bowler).
+  Use a more efficient absolute value calculation on SSE2 (Matthieu Darbois).
+  Fixed the case where PNG_IMAGE_BUFFER_SIZE can overflow in the application
+    as a result of the application using an increased 'row_stride'; previously
+    png_image_finish_read only checked for overflow on the base calculation of
+    components.  (I.e. it checked for overflow of a 32-bit number on the total
+    number of pixel components in the output format, not the possibly padded row
+    length and not the number of bytes, which for linear formats is twice the
+    number of components.)
+  MSVC does not like '-(unsigned)', so replaced it with 0U-(unsigned)
+  MSVC does not like (uInt) = -(unsigned) (i.e. as an initializer), unless
+    the conversion is explicitly invoked by a cast.
+  Put the SKIP definition in the correct place. It needs to come after the
+    png.h include (see all the other .c files in contrib/libtests) because it
+    depends on PNG_LIBPNG_VER.
+  Removed the three compile warning options from the individual project
+    files into the zlib.props globals.  It increases the warning level from 4
+    to All and adds a list of the warnings that need to be turned off.  This is
+    semi-documentary; the intent is to tell libpng users which warnings have
+    been examined and judged non-fixable at present.  The warning about
+    structure padding is fixable, but it would be a signficant change (moving
+    structure members around).
+
+Version 1.6.24beta03 [July 4, 2016]
+  Optimized absolute value calculation in filter selection, similar to
+    code in the PAETH decoder in pngrutil.c. Build with PNG_USE_ABS to
+    use this.
+  Added pngcp to the build together with a pngcp.dfa configuration test.
+  Added high resolution timing to pngcp.
+  Added "Common linking failures" section to INSTALL.
+  Relocated misplaced #endif in png.c sRGB profile checking.
+  Fixed two Coverity issues in pngcp.c.
+
+Version 1.6.24beta04 [July 8, 2016]
+  Avoid filter-selection heuristic sum calculations in cases where only one
+    filter is a candidate for selection. This trades off code size (added
+    private png_setup_*_row_only() functions) for speed.
+
+Version 1.6.24beta05 [July 13, 2016]
+  Fixed some indentation to comply with our coding style.
+
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement

CMakeLists.txt

@@ -35,7 +35,7 @@ enable_testing()
 
 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 6)
-set(PNGLIB_RELEASE 22)
+set(PNGLIB_RELEASE 24)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})
 
@@ -696,7 +696,7 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)
 # SET UP LINKS
 if(PNG_SHARED)
   set_target_properties(png PROPERTIES
-#   VERSION 16.${PNGLIB_RELEASE}.1.6.22rc01
+#   VERSION 16.${PNGLIB_RELEASE}.1.6.24beta05
     VERSION 16.${PNGLIB_RELEASE}.0
     SOVERSION 16
     CLEAN_DIRECT_OUTPUT 1)

INSTALL

@@ -18,7 +18,8 @@ VIII. Configuring libpng for 16-bit platforms
 XIII. Removing unwanted object code
  XIV. Changes to the build and configuration of libpng in libpng-1.5.x
   XV. Setjmp/longjmp issues
- XVI. Other sources of information about libpng
+ XVI. Common linking failures
+XVII. Other sources of information about libpng
 
 I. Simple installation
 
@@ -78,7 +79,7 @@ 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; otherwise go to http://zlib.net.  You can place
-zlib in in the same directory as libpng or in another directory.
+zlib 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
@@ -118,8 +119,8 @@ or "zlib128") so that you have directories called "zlib" and "libpng".
 
 Your directory structure should look like this:
 
-   ..       (the parent directory)
-      libpng  (this directory)
+   .. (the parent directory)
+      libpng (this directory)
           INSTALL (this file)
           README
           *.h, *.c  => libpng source files
@@ -382,28 +383,20 @@ This requires setjmp/longjmp, so you must either build the library
 with PNG_SETJMP_SUPPORTED defined, or with PNG_SIMPLIFIED_READ_SUPPORTED
 and PNG_SIMPLIFIED_WRITE_SUPPORTED undefined.
 
-XVI. Other sources of information about libpng:
+XVI. Common linking failures
+
+If your application fails to find libpng or zlib entries while linking:
+
+  Be sure "-lz" appears after "-lpng" on your linking command.
+
+  Be sure you have built libpng, zlib, and your application for the
+  same platform (e.g., 32-bit or 64-bit).
+
+  If you are using the vstudio project, observe the WARNING in
+  project/vstudio/README.txt.
+
+XVII. 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.
-
-Using the ./configure script -- 16 December 2002.
-=================================================
-
-The ./configure script should work compatibly with what scripts/makefile.*
-did, however there are some options you might need to add to configure
-explicitly, which previously was done semi-automatically (if you didn't edit
-scripts/makefile.* yourself, that is)
-
-CFLAGS="-Wall -O -funroll-loops \
--malign-loops=2 -malign-functions=2" ./configure --prefix=/usr/include \
---with-pkgconfigdir=/usr/lib/pkgconfig --includedir=/usr/include
-
-You can alternatively specify --includedir=/usr/include, /usr/local/include,
-/usr/include/libpng16, 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",
-"Makefile.in", and the other configuration files. Then try configure again.
-

LICENSE

@@ -10,7 +10,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000 through 1.6.22rc01, May 14, 2016 are
+libpng versions 1.0.7, July 1, 2000 through 1.6.24beta05, July 13, 2016 are
 Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, and are distributed according to the same
 disclaimer and license as libpng-1.0.6 with the following individuals
@@ -127,4 +127,4 @@ any encryption software.  See the EAR, paragraphs 734.3(b)(3) and
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-May 14, 2016
+July 13, 2016

Makefile.am

@@ -12,10 +12,13 @@ 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 pngimage timepng
+check_PROGRAMS= pngtest pngunknown pngstest pngvalid pngimage
+if HAVE_CLOCK_GETTIME
+check_PROGRAMS += timepng
+endif
 
 # Utilities - installed
-bin_PROGRAMS= pngfix png-fix-itxt
+bin_PROGRAMS= pngcp 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,
@@ -50,6 +53,9 @@ pngfix_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
 
 png_fix_itxt_SOURCES = contrib/tools/png-fix-itxt.c
 
+pngcp_SOURCES = contrib/tools/pngcp.c
+pngcp_LDADD = libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.la
+
 # Generally these are single line shell scripts to run a test with a particular
 # set of parameters:
 TESTS =\
@@ -227,6 +233,7 @@ contrib/libtests/timepng.o: pnglibconf.h
 
 contrib/tools/makesRGB.o: pnglibconf.h
 contrib/tools/pngfix.o: pnglibconf.h
+contrib/tools/pngcp.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

README

@@ -1,4 +1,4 @@
-README for libpng version 1.6.22rc01 - May 14, 2016 (shared library 16.0)
+README for libpng version 1.6.24beta05 - July 13, 2016 (shared library 16.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.

arm/arm_init.c

@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2014,2016 Glenn Randers-Pehrson
  * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.22 [May 26, 2016]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

arm/filter_neon_intrinsics.c

@@ -5,7 +5,7 @@
  * 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 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.22 [May 26, 2016]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

configure.ac

@@ -1,7 +1,7 @@
 # configure.ac
 
 # Copyright (c) 2004-2015 Glenn Randers-Pehrson
-# Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+# Last changed in libpng 1.6.22 [May 26, 2016]
 
 # This code is released under the libpng license.
 # For conditions of distribution and use, see the disclaimer
@@ -25,7 +25,7 @@ AC_PREREQ([2.68])
 
 dnl Version number stuff here:
 
-AC_INIT([libpng],[1.6.22rc01],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.24beta05],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])
 
 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -46,10 +46,10 @@ 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=1.6.22rc01
+PNGLIB_VERSION=1.6.24beta05
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=22
+PNGLIB_RELEASE=24
 
 dnl End of version number stuff
 
@@ -146,6 +146,12 @@ AC_C_RESTRICT
 AC_FUNC_STRTOD
 AC_CHECK_FUNCS([memset], , AC_MSG_ERROR(memset not found in libc))
 AC_CHECK_FUNCS([pow], , AC_CHECK_LIB(m, pow, , AC_MSG_ERROR(cannot find pow)) )
+
+# Some later POSIX 1003.1 functions are required for test programs, failure here
+# is soft (the corresponding test program is not built).
+AC_CHECK_FUNC([clock_gettime],,[AC_MSG_WARN([not building timepng])])
+AM_CONDITIONAL([HAVE_CLOCK_GETTIME], [test "$ac_cv_func_clock_gettime" = "yes"])
+
 AC_ARG_WITH(zlib-prefix,
    AS_HELP_STRING([[[--with-zlib-prefix]]],
       [prefix that may have been used in installed zlib]),

contrib/conftest/pngcp.dfa

@@ -0,0 +1,57 @@
+# pngcp.dfa
+#  Build time configuration of libpng
+#
+# Author: John Bowler
+# Copyright: (c) John Bowler, 2016
+# 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 support for pngcp.  This means just png_read_png,
+# png_write_png and small number of configuration settings.
+#
+everything = off
+
+# This option is specific to this configuration; it adds a #define to the
+# generated pnglibconf.h which turns on the (not portable) timing option for
+# pngcp.  Note that any option is automatically preceded by PNG_; there is no
+# way round this and this is deliberate.
+option PNGCP_TIMING
+
+# Because of the everything off above the option must also be turned on.  This
+# may not be done in one step because it is safer and avoids mis-spelled options
+# in user .dfa files to error out if an unrecognized option is turned on.
+option PNGCP_TIMING on
+
+# Options to turn on png_read_png and png_write_png:
+option INFO_IMAGE on
+option SEQUENTIAL_READ on
+option EASY_ACCESS on
+option WRITE on
+option WRITE_16BIT on
+option WRITE_FILTER on
+
+# pngcp needs this to preserve unknown chunks, switching all these on means that
+# pngcp can work without explicit known chunk reading suppport
+option UNKNOWN_CHUNKS on
+option SET_UNKNOWN_CHUNKS on
+option HANDLE_AS_UNKNOWN on
+option SAVE_UNKNOWN_CHUNKS on
+option WRITE_UNKNOWN_CHUNKS on
+
+# pngcp needs this to handle palette files with invalid indices:
+option CHECK_FOR_INVALID_INDEX on
+option GET_PALETTE_MAX on
+
+# Pre-libpng 1.7 pngcp has to stash text chunks manually, post 1.7 without this
+# text chunks should be handled as unknown ok.
+option TEXT on
+
+# this is used to turn off limits:
+option USER_LIMITS on
+option SET_USER_LIMITS on
+
+# these are are just required for specific customizations
+option WRITE_CUSTOMIZE_ZTXT_COMPRESSION on
+option WRITE_CUSTOMIZE_COMPRESSION on

contrib/gregbook/readpng2.c

@@ -54,7 +54,7 @@
   ---------------------------------------------------------------------------
 
    Changelog:
-     %RDATE% - Check return value of png_get_bKGD() (Glenn R-P)
+     2015-11-12 - Check return value of png_get_bKGD() (Glenn R-P)
 
   ---------------------------------------------------------------------------*/
 

contrib/intel/INSTALL

@@ -46,16 +46,7 @@ following the instructions below, then follow the instructions in
 section II of INSTALL in the main libpng directory, then configure libpng
 with -DPNG_INTEL_SSE in CPPFLAGS.
 
-1. Insert the following lines above the copyright line near the top of
-configure.ac:
-
------------------cut----------------
-# Copyright (c) 2016 Google, Inc.
-# Written by Mike Klein and Matt Sarett
-# Derived from the ARM supporting code in libpng/configure.ac, which was
------------------cut----------------
-
-2. Add the following code to configure.ac under HOST SPECIFIC OPTIONS
+1. Add the following code to configure.ac under HOST SPECIFIC OPTIONS
 directly beneath the section for ARM:
 
 -----------------cut----------------
@@ -95,16 +86,7 @@ AM_CONDITIONAL([PNG_INTEL_SSE],
     esac])
 -----------------cut----------------
 
-3. Insert the following lines above the copyright line near the top of
-Makefile.am:
-
------------------cut----------------
-# Copyright (c) 2016 Google, Inc.
-# Written by Mike Klein and Matt Sarett
-# Derived from the ARM supporting code in libpng/configure.ac, which was
------------------cut----------------
-
-4. Add the following code to Makefile.am under HOST SPECIFIC OPTIONS
+2. Add the following code to Makefile.am under HOST SPECIFIC OPTIONS
 directly beneath the "if PNG_ARM_NEON ... endif" statement:
 
 -----------------cut----------------
@@ -114,7 +96,7 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SOURCES += contrib/intel/intel_init.c\
 endif
 -----------------cut----------------
 
-5. Add the following lines to pngpriv.h, following the PNG_ARM_NEON_OPT
+3. Add the following lines to pngpriv.h, following the PNG_ARM_NEON_OPT
 code:
 
 -----------------cut----------------
@@ -156,7 +138,7 @@ code:
 
 -----------------cut----------------
 
-5. Add the following lines to pngpriv.h, following the prototype for
+4. Add the following lines to pngpriv.h, following the prototype for
 png_read_filter_row_paeth4_neon:
 
 -----------------cut----------------

contrib/intel/filter_sse2_intrinsics.c

@@ -6,7 +6,7 @@
  * Derived from arm/filter_neon_intrinsics.c, which was
  * Copyright (c) 2014,2016 Glenn Randers-Pehrson
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -208,7 +208,7 @@ static __m128i abs_i16(__m128i x) {
    x = _mm_xor_si128(x, is_negative);
 
    /* +1 to negative lanes, else +0. */
-   x = _mm_add_epi16(x, _mm_srli_epi16(is_negative, 15));
+   x = _mm_sub_epi16(x, is_negative);
    return x;
 #endif
 }

contrib/intel/intel_init.c

@@ -6,7 +6,7 @@
  * Derived from arm/arm_init.c, which was
  * Copyright (c) 2014,2016 Glenn Randers-Pehrson
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.22 [May 26, 2016]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer

contrib/intel/intel_sse.patch

@@ -1,21 +1,7 @@
 diff --git a/configure.ac b/configure.ac
---- a/configure.ac	2016-04-27 22:33:47.805069558 -0500
-+++ b/configure.ac	2016-04-27 22:33:47.829012469 -0500
-@@ -1,10 +1,13 @@
- # configure.ac
- 
-+# Copyright (c) 2016 Google, Inc.
-+# Written by Mike Klein and Matt Sarett
-+# Derived from the ARM supporting code in libpng/configure.ac, which was
- # Copyright (c) 2004-2015 Glenn Randers-Pehrson
- # Last changed in libpng 1.6.22 [(PENDING RELEASE)]
- 
- # This code is released under the libpng license.
- # For conditions of distribution and use, see the disclaimer
- # and license in png.h
- 
- dnl Process this file with autoconf to produce a configure script.
-@@ -335,16 +338,50 @@ AC_ARG_ENABLE([arm-neon],
+--- a/configure.ac	2016-05-25 18:59:10.000000000 -0400
++++ b/configure.ac	2016-05-25 19:48:10.631751170 -0400
+@@ -341,16 +341,50 @@ AC_ARG_ENABLE([arm-neon],
  
  AM_CONDITIONAL([PNG_ARM_NEON],
     [test "$enable_arm_neon" != 'no' &&
@@ -67,23 +53,9 @@ diff --git a/configure.ac b/configure.ac
  
  AC_OUTPUT
 diff --git a/Makefile.am b/Makefile.am
---- a/Makefile.am	2016-04-27 22:33:47.809928404 -0500
-+++ b/Makefile.am	2016-04-27 22:33:47.832941146 -0500
-@@ -1,10 +1,13 @@
- # Makefile.am, the source file for Makefile.in (and hence Makefile), is
- #
-+# Copyright (c) 2016 Google, Inc.
-+# Written by Mike Klein and Matt Sarett
-+# Derived from the ARM supporting code in libpng/configure.ac, which was
- # Copyright (c) 2004-2016 Glenn Randers-Pehrson
- # Last changed in libpng 1.6.22 [(PENDING RELEASE)]
- #
- # This code is released under the libpng license.
- # For conditions of distribution and use, see the disclaimer
- # and license in png.h
- 
- PNGLIB_BASENAME= libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@
-@@ -86,16 +89,20 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SO
+--- a/Makefile.am	2016-05-17 18:15:12.000000000 -0400
++++ b/Makefile.am	2016-05-25 19:48:10.631751170 -0400
+@@ -89,16 +89,20 @@ libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@_la_SO
  	pngset.c pngtrans.c pngwio.c pngwrite.c pngwtran.c pngwutil.c\
  	png.h pngconf.h pngdebug.h pnginfo.h pngpriv.h pngstruct.h pngusr.dfa
  
@@ -105,8 +77,8 @@ diff --git a/Makefile.am b/Makefile.am
  #   Versioned symbols and restricted exports
  if HAVE_SOLARIS_LD
 diff --git a/pngpriv.h b/pngpriv.h
---- a/pngpriv.h	2016-04-27 22:33:47.800157005 -0500
-+++ b/pngpriv.h	2016-04-27 22:33:47.838191194 -0500
+--- a/pngpriv.h	2016-05-31 09:20:34.442885047 -0500
++++ b/pngpriv.h	2016-05-31 09:14:54.583492341 -0500
 @@ -177,16 +177,52 @@
  #  endif /* !PNG_ARM_NEON_IMPLEMENTATION */
  
@@ -190,3 +162,22 @@ diff --git a/pngpriv.h b/pngpriv.h
  PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
     png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
     /* Read 'avail_out' bytes of data from the IDAT stream.  If the output buffer
+@@ -1910,16 +1959,18 @@ PNG_INTERNAL_FUNCTION(void, PNG_FILTER_O
+    /* 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);
++PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
++   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
+ #endif
+ 
+ PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
+    png_const_charp key, png_bytep new_key), PNG_EMPTY);
+ 
+ /* Maintainer: Put new private prototypes here ^ */
+ 
+ #include "pngdebug.h"

contrib/libtests/pngimage.c

@@ -2,7 +2,7 @@
  *
  * Copyright (c) 2015,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -45,8 +45,19 @@
 #  define SKIP 0
 #endif
 
-#if defined(PNG_INFO_IMAGE_SUPPORTED) && defined(PNG_SEQUENTIAL_READ_SUPPORTED)\
-    && (defined(PNG_READ_PNG_SUPPORTED) || PNG_LIBPNG_VER < 10700)
+#if PNG_LIBPNG_VER < 10700
+   /* READ_PNG and WRITE_PNG were not defined, so: */
+#  ifdef PNG_INFO_IMAGE_SUPPORTED
+#     ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+#        define PNG_READ_PNG_SUPPORTED
+#     endif /* SEQUENTIAL_READ */
+#     ifdef PNG_WRITE_SUPPORTED
+#        define PNG_WRITE_PNG_SUPPORTED
+#     endif /* WRITE */
+#  endif /* INFO_IMAGE */
+#endif /* pre 1.7.0 */
+
+#ifdef PNG_READ_PNG_SUPPORTED
 /* If a transform is valid on both read and write this implies that if the
  * transform is applied to read it must also be applied on write to produce
  * meaningful data.  This is because these transforms when performed on read
@@ -395,7 +406,7 @@ buffer_destroy(struct buffer *buffer)
    buffer_destroy_list(list);
 }
 
-#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_PNG_SUPPORTED
 static void
 buffer_start_write(struct buffer *buffer)
 {
@@ -565,7 +576,7 @@ struct display
    png_structp    read_pp;
    png_infop      read_ip;
 
-#  ifdef PNG_WRITE_SUPPORTED
+#  ifdef PNG_WRITE_PNG_SUPPORTED
       /* Used to write a new image (the original info_ptr is used) */
       png_structp   write_pp;
       struct buffer written_file;   /* where the file gets written */
@@ -592,7 +603,7 @@ display_init(struct display *dp)
    dp->read_ip = NULL;
    buffer_init(&dp->original_file);
 
-#  ifdef PNG_WRITE_SUPPORTED
+#  ifdef PNG_WRITE_PNG_SUPPORTED
       dp->write_pp = NULL;
       buffer_init(&dp->written_file);
 #  endif
@@ -605,7 +616,7 @@ display_clean_read(struct display *dp)
       png_destroy_read_struct(&dp->read_pp, &dp->read_ip, NULL);
 }
 
-#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_PNG_SUPPORTED
 static void
 display_clean_write(struct display *dp)
 {
@@ -617,7 +628,7 @@ display_clean_write(struct display *dp)
 static void
 display_clean(struct display *dp)
 {
-#  ifdef PNG_WRITE_SUPPORTED
+#  ifdef PNG_WRITE_PNG_SUPPORTED
       display_clean_write(dp);
 #  endif
    display_clean_read(dp);
@@ -635,7 +646,7 @@ static void
 display_destroy(struct display *dp)
 {
     /* Release any memory held in the display. */
-#  ifdef PNG_WRITE_SUPPORTED
+#  ifdef PNG_WRITE_PNG_SUPPORTED
       buffer_destroy(&dp->written_file);
 #  endif
 
@@ -1082,6 +1093,7 @@ compare_read(struct display *dp, int applied_transforms)
       }
 
       else
+#     ifdef PNG_sBIT_SUPPORTED
       {
          unsigned long y;
          int bpp;   /* bits-per-pixel then bytes-per-pixel */
@@ -1243,12 +1255,16 @@ compare_read(struct display *dp, int applied_transforms)
             }
          } /* for y */
       }
+#     else /* !sBIT */
+         display_log(dp, INTERNAL_ERROR,
+               "active shift transform but no sBIT support");
+#     endif /* !sBIT */
    }
 
    return 1; /* compare succeeded */
 }
 
-#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_PNG_SUPPORTED
 static void
 buffer_write(struct display *dp, struct buffer *buffer, png_bytep data,
    png_size_t size)
@@ -1347,7 +1363,7 @@ write_png(struct display *dp, png_infop ip, int transforms)
     */
    display_clean_write(dp);
 }
-#endif /* WRITE_SUPPORTED */
+#endif /* WRITE_PNG */
 
 static int
 skip_transform(struct display *dp, int tr)
@@ -1409,7 +1425,7 @@ test_one_file(struct display *dp, const char *filename)
          return; /* no point testing more */
    }
 
-#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_PNG_SUPPORTED
    /* Second test: write the original PNG data out to a new file (to test the
     * write side) then read the result back in and make sure that it hasn't
     * changed.
@@ -1450,7 +1466,7 @@ test_one_file(struct display *dp, const char *filename)
           * out and read it back in again (without the reversible transforms)
           * we should get back to the place where we started.
           */
-#ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_PNG_SUPPORTED
          if ((current & write_transforms) == current)
          {
             /* All transforms reversible: write the PNG with the transformations
@@ -1686,7 +1702,7 @@ main(const int argc, const char * const * const argv)
       return errors != 0;
    }
 }
-#else /* !INFO_IMAGE || !SEQUENTIAL_READ || !READ_PNG*/
+#else /* !READ_PNG */
 int
 main(void)
 {

contrib/libtests/pngstest.c

@@ -3,7 +3,7 @@
  *
  * Copyright (c) 2013-2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -26,15 +26,6 @@
 #  include <config.h>
 #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 && defined(HAVE_CONFIG_H)
-#  define SKIP 77
-#else
-#  define SKIP 0
-#endif
-
 /* Define the following to use this test against your installed libpng, rather
  * than the one being built here:
  */
@@ -44,6 +35,15 @@
 #  include "../../png.h"
 #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 && defined(HAVE_CONFIG_H)
+#  define SKIP 77
+#else
+#  define SKIP 0
+#endif
+
 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED /* Else nothing can be done */
 #include "../tools/sRGB.h"
 

contrib/libtests/pngunknown.c

@@ -1,7 +1,7 @@
 
 /* pngunknown.c - test the read side unknown chunk handling
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.22 [May 26, 2016]
  * Copyright (c) 2015,2016 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *

contrib/libtests/pngvalid.c

@@ -1,7 +1,7 @@
 
 /* pngvalid.c - validate libpng by constructing then reading png files.
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
  * Copyright (c) 2014-2016 Glenn Randers-Pehrson
  * Written by John Cunningham Bowler
  *
@@ -131,6 +131,17 @@ typedef png_byte *png_const_bytep;
 #include <string.h> /* For memcpy, memset */
 #include <math.h>   /* For floor */
 
+/* Convenience macros. */
+#define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d))
+#define CHUNK_IHDR CHUNK(73,72,68,82)
+#define CHUNK_PLTE CHUNK(80,76,84,69)
+#define CHUNK_IDAT CHUNK(73,68,65,84)
+#define CHUNK_IEND CHUNK(73,69,78,68)
+#define CHUNK_cHRM CHUNK(99,72,82,77)
+#define CHUNK_gAMA CHUNK(103,65,77,65)
+#define CHUNK_sBIT CHUNK(115,66,73,84)
+#define CHUNK_sRGB CHUNK(115,82,71,66)
+
 /* Unused formal parameter errors are removed using the following macro which is
  * expected to have no bad effects on performance.
  */
@@ -297,38 +308,33 @@ randomize(void *pv, size_t size)
 
 #define R8(this) randomize(&(this), sizeof (this))
 
-static void r16(png_uint_16p p16, size_t count)
+#ifdef PNG_READ_SUPPORTED
+static png_byte
+random_byte(void)
 {
-   size_t i;
-
-   for (i=0; i<count; ++i)
-   {
-      unsigned char b2[2];
-      randomize(b2, sizeof b2);
-      *p16++ = png_get_uint_16(b2);
-   }
+   unsigned char b1[1];
+   randomize(b1, sizeof b1);
+   return b1[0];
 }
+#endif /* READ */
 
-#define R16(this) r16(&(this), (sizeof (this))/(sizeof (png_uint_16)))
-#define R16_1(this) r16(&(this), (size_t) 1U)
+static png_uint_16
+random_u16(void)
+{
+   unsigned char b2[2];
+   randomize(b2, sizeof b2);
+   return png_get_uint_16(b2);
+}
 
 #if defined PNG_READ_RGB_TO_GRAY_SUPPORTED ||\
     defined PNG_READ_FILLER_SUPPORTED
-static void r32(png_uint_32p p32, size_t count)
+static png_uint_32
+random_u32(void)
 {
-   size_t i;
-
-   for (i=0; i<count; ++i)
-   {
-      unsigned char b4[4];
-      randomize(b4, sizeof b4);
-      *p32++ = png_get_uint_32(b4);
-   }
+   unsigned char b4[4];
+   randomize(b4, sizeof b4);
+   return png_get_uint_32(b4);
 }
-
-#define R32(this) r32(&(this), (sizeof (this))/(sizeof (png_uint_32)))
-#define R32_1(this) r32(&(this), (size_t) 1U)
-
 #endif /* READ_FILLER || READ_RGB_TO_GRAY */
 
 #endif /* READ || WRITE_tRNS || WRITE_FILTER */
@@ -338,11 +344,7 @@ static void r32(png_uint_32p p32, size_t count)
 static unsigned int
 random_mod(unsigned int max)
 {
-   png_uint_16 x;
-
-   R16_1(x);
-
-   return x % max; /* 0 .. max-1 */
+   return random_u16() % max; /* 0 .. max-1 */
 }
 #endif /* READ_TRANSFORMS || WRITE_FILTER */
 
@@ -351,11 +353,7 @@ random_mod(unsigned int max)
 static int
 random_choice(void)
 {
-   unsigned char x;
-
-   R8(x);
-
-   return x & 1;
+   return random_byte() & 1;
 }
 #endif /* READ_RGB_TO_GRAY || READ_FILLER */
 
@@ -711,6 +709,8 @@ typedef struct png_store_file
 {
    struct png_store_file*  next;      /* as many as you like... */
    char                    name[FILE_NAME_SIZE];
+   unsigned int            IDAT_bits; /* Number of bits in IDAT size */
+   png_uint_32             IDAT_size; /* Total size of IDAT data */
    png_uint_32             id;        /* must be correct (see FILEID) */
    png_size_t              datacount; /* In this (the last) buffer */
    png_store_buffer        data;      /* Last buffer in file */
@@ -766,6 +766,13 @@ typedef struct png_store
    char               test[128];      /* Name of test */
    char               error[256];
 
+   /* Share fields */
+   png_uint_32        chunklen; /* Length of chunk+overhead (chunkpos >= 8) */
+   png_uint_32        chunktype;/* Type of chunk (valid if chunkpos >= 4) */
+   png_uint_32        chunkpos; /* Position in chunk */
+   png_uint_32        IDAT_size;/* Accumulated IDAT size in .new */
+   unsigned int       IDAT_bits;/* Cache of the file store value */
+
    /* Read fields */
    png_structp        pread;    /* Used to read a saved file */
    png_infop          piread;
@@ -775,6 +782,9 @@ typedef struct png_store
    png_byte*          image;    /* Buffer for reading interlaced images */
    png_size_t         cb_image; /* Size of this buffer */
    png_size_t         cb_row;   /* Row size of the image(s) */
+   uLong              IDAT_crc;
+   png_uint_32        IDAT_len; /* Used when re-chunking IDAT chunks */
+   png_uint_32        IDAT_pos; /* Used when re-chunking IDAT chunks */
    png_uint_32        image_h;  /* Number of rows in a single image */
    store_pool         read_memory_pool;
 
@@ -861,6 +871,11 @@ store_init(png_store* ps)
    ps->pwrite = NULL;
    ps->piwrite = NULL;
    ps->writepos = 0;
+   ps->chunkpos = 8;
+   ps->chunktype = 0;
+   ps->chunklen = 16;
+   ps->IDAT_size = 0;
+   ps->IDAT_bits = 0;
    ps->new.prev = NULL;
    ps->palette = NULL;
    ps->npalette = 0;
@@ -883,6 +898,11 @@ store_freenew(png_store *ps)
 {
    store_freebuffer(&ps->new);
    ps->writepos = 0;
+   ps->chunkpos = 8;
+   ps->chunktype = 0;
+   ps->chunklen = 16;
+   ps->IDAT_size = 0;
+   ps->IDAT_bits = 0;
    if (ps->palette != NULL)
    {
       free(ps->palette);
@@ -896,9 +916,6 @@ store_storenew(png_store *ps)
 {
    png_store_buffer *pb;
 
-   if (ps->writepos != STORE_BUFFER_SIZE)
-      png_error(ps->pwrite, "invalid store call");
-
    pb = voidcast(png_store_buffer*, malloc(sizeof *pb));
 
    if (pb == NULL)
@@ -929,21 +946,52 @@ store_freefile(png_store_file **ppf)
    }
 }
 
+static unsigned int
+bits_of(png_uint_32 num)
+{
+   /* Return the number of bits in 'num' */
+   unsigned int b = 0;
+
+   if (num & 0xffff0000U)  b += 16U, num >>= 16;
+   if (num & 0xff00U)      b += 8U, num >>= 8;
+   if (num & 0xf0U)        b += 4U, num >>= 4;
+   if (num & 0xcU)         b += 2U, num >>= 2;
+   if (num & 0x2U)         ++b, num >>= 1;
+   if (num)                ++b;
+
+   return b; /* 0..32 */
+}
+
 /* Main interface to file storeage, after writing a new PNG file (see the API
  * below) call store_storefile to store the result with the given name and id.
  */
 static void
 store_storefile(png_store *ps, png_uint_32 id)
 {
-   png_store_file *pf = voidcast(png_store_file*, malloc(sizeof *pf));
+   png_store_file *pf;
+
+   if (ps->chunkpos != 0U || ps->chunktype != 0U || ps->chunklen != 0U ||
+       ps->IDAT_size == 0)
+      png_error(ps->pwrite, "storefile: incomplete write");
+
+   pf = voidcast(png_store_file*, malloc(sizeof *pf));
    if (pf == NULL)
       png_error(ps->pwrite, "storefile: OOM");
    safecat(pf->name, sizeof pf->name, 0, ps->wname);
    pf->id = id;
    pf->data = ps->new;
    pf->datacount = ps->writepos;
+   pf->IDAT_size = ps->IDAT_size;
+   pf->IDAT_bits = bits_of(ps->IDAT_size);
+   /* Because the IDAT always has zlib header stuff this must be true: */
+   if (pf->IDAT_bits == 0U)
+      png_error(ps->pwrite, "storefile: 0 sized IDAT");
    ps->new.prev = NULL;
    ps->writepos = 0;
+   ps->chunkpos = 8;
+   ps->chunktype = 0;
+   ps->chunklen = 16;
+   ps->IDAT_size = 0;
    pf->palette = ps->palette;
    pf->npalette = ps->npalette;
    ps->palette = 0;
@@ -1209,32 +1257,119 @@ store_image_check(const png_store* ps, png_const_structp pp, int iImage)
 }
 #endif /* PNG_READ_SUPPORTED */
 
+static int
+valid_chunktype(png_uint_32 chunktype)
+{
+   /* Each byte in the chunk type must be in one of the ranges 65..90, 97..122
+    * (both inclusive), so:
+    */
+   unsigned int i;
+
+   for (i=0; i<4; ++i)
+   {
+      unsigned int c = chunktype & 0xffU;
+
+      if (!((c >= 65U && c <= 90U) || (c >= 97U && c <= 122U)))
+         return 0;
+
+      chunktype >>= 8;
+   }
+
+   return 1; /* It's valid */
+}
+
 static void PNGCBAPI
 store_write(png_structp ppIn, png_bytep pb, png_size_t st)
 {
    png_const_structp pp = ppIn;
    png_store *ps = voidcast(png_store*, png_get_io_ptr(pp));
+   size_t writepos = ps->writepos;
+   png_uint_32 chunkpos = ps->chunkpos;
+   png_uint_32 chunktype = ps->chunktype;
+   png_uint_32 chunklen = ps->chunklen;
 
    if (ps->pwrite != pp)
       png_error(pp, "store state damaged");
 
+   /* Technically this is legal, but in practice libpng never writes more than
+    * the maximum chunk size at once so if it happens something weird has
+    * changed inside libpng (probably).
+    */
+   if (st > 0x7fffffffU)
+      png_error(pp, "unexpected write size");
+
+   /* Now process the bytes to be written.  Do this in units of the space in the
+    * output (write) buffer or, at the start 4 bytes for the chunk type and
+    * length limited in any case by the amount of data.
+    */
    while (st > 0)
    {
-      size_t cb;
+      if (writepos >= STORE_BUFFER_SIZE)
+         store_storenew(ps), writepos = 0;
 
-      if (ps->writepos >= STORE_BUFFER_SIZE)
-         store_storenew(ps);
+      if (chunkpos < 4)
+      {
+         png_byte b = *pb++;
+         --st;
+         chunklen = (chunklen << 8) + b;
+         ps->new.buffer[writepos++] = b;
+         ++chunkpos;
+      }
 
-      cb = st;
+      else if (chunkpos < 8)
+      {
+         png_byte b = *pb++;
+         --st;
+         chunktype = (chunktype << 8) + b;
+         ps->new.buffer[writepos++] = b;
 
-      if (cb > STORE_BUFFER_SIZE - ps->writepos)
-         cb = STORE_BUFFER_SIZE - ps->writepos;
+         if (++chunkpos == 8)
+         {
+            chunklen &= 0xffffffffU;
+            if (chunklen > 0x7fffffffU)
+               png_error(pp, "chunk length too great");
 
-      memcpy(ps->new.buffer + ps->writepos, pb, cb);
-      pb += cb;
-      st -= cb;
-      ps->writepos += cb;
-   }
+            chunktype &= 0xffffffffU;
+            if (chunktype == CHUNK_IDAT)
+            {
+               if (chunklen > ~ps->IDAT_size)
+                  png_error(pp, "pngvalid internal image too large");
+
+               ps->IDAT_size += chunklen;
+            }
+
+            else if (!valid_chunktype(chunktype))
+               png_error(pp, "invalid chunk type");
+
+            chunklen += 12; /* for header and CRC */
+         }
+      }
+
+      else /* chunkpos >= 8 */
+      {
+         png_size_t cb = st;
+
+         if (cb > STORE_BUFFER_SIZE - writepos)
+            cb = STORE_BUFFER_SIZE - writepos;
+
+         if (cb  > chunklen - chunkpos/* bytes left in chunk*/)
+            cb = (png_size_t)/*SAFE*/(chunklen - chunkpos);
+
+         memcpy(ps->new.buffer + writepos, pb, cb);
+         chunkpos += (png_uint_32)/*SAFE*/cb;
+         pb += cb;
+         writepos += cb;
+         st -= cb;
+
+         if (chunkpos >= chunklen) /* must be equal */
+            chunkpos = chunktype = chunklen = 0;
+      }
+   } /* while (st > 0) */
+
+   ps->writepos = writepos;
+   ps->chunkpos = chunkpos;
+   ps->chunktype = chunktype;
+   ps->chunklen = chunklen;
 }
 
 static void PNGCBAPI
@@ -1254,7 +1389,6 @@ store_read_buffer_size(png_store *ps)
    return ps->current->datacount;
 }
 
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
 /* Return total bytes available for read. */
 static size_t
 store_read_buffer_avail(png_store *ps)
@@ -1279,7 +1413,6 @@ store_read_buffer_avail(png_store *ps)
 
    return 0;
 }
-#endif
 
 static int
 store_read_buffer_next(png_store *ps)
@@ -1331,6 +1464,240 @@ store_read_imp(png_store *ps, png_bytep pb, png_size_t st)
    }
 }
 
+static png_size_t
+store_read_chunk(png_store *ps, png_bytep pb, const png_size_t max,
+      const png_size_t min)
+{
+   png_uint_32 chunklen = ps->chunklen;
+   png_uint_32 chunktype = ps->chunktype;
+   png_uint_32 chunkpos = ps->chunkpos;
+   png_size_t st = max;
+
+   if (st > 0) do
+   {
+      if (chunkpos >= chunklen) /* end of last chunk */
+      {
+         png_byte buffer[8];
+
+         /* Read the header of the next chunk: */
+         store_read_imp(ps, buffer, 8U);
+         chunklen = png_get_uint_32(buffer) + 12U;
+         chunktype = png_get_uint_32(buffer+4U);
+         chunkpos = 0U; /* Position read so far */
+      }
+
+      if (chunktype == CHUNK_IDAT)
+      {
+         png_uint_32 IDAT_pos = ps->IDAT_pos;
+         png_uint_32 IDAT_len = ps->IDAT_len;
+         png_uint_32 IDAT_size = ps->IDAT_size;
+
+         /* The IDAT headers are constructed here; skip the input header. */
+         if (chunkpos < 8U)
+            chunkpos = 8U;
+
+         if (IDAT_pos == IDAT_len)
+         {
+            png_byte random = random_byte();
+
+            /* Make a new IDAT chunk, if IDAT_len is 0 this is the first IDAT,
+             * if IDAT_size is 0 this is the end.  At present this is set up
+             * using a random number so that there is a 25% chance before
+             * the start of the first IDAT chunk being 0 length.
+             */
+            if (IDAT_len == 0U) /* First IDAT */
+            {
+               switch (random & 3U)
+               {
+                  case 0U: IDAT_len = 12U; break; /* 0 bytes */
+                  case 1U: IDAT_len = 13U; break; /* 1 byte */
+                  default: IDAT_len = random_u32();
+                           IDAT_len %= IDAT_size;
+                           IDAT_len += 13U; /* 1..IDAT_size bytes */
+                           break;
+               }
+            }
+
+            else if (IDAT_size == 0U) /* all IDAT data read */
+            {
+               /* The last (IDAT) chunk should be positioned at the CRC now: */
+               if (chunkpos != chunklen-4U)
+                  png_error(ps->pread, "internal: IDAT size mismatch");
+
+               /* The only option here is to add a zero length IDAT, this
+                * happens 25% of the time.  Because of the check above
+                * chunklen-4U-chunkpos must be zero, we just need to skip the
+                * CRC now.
+                */
+               if ((random & 3U) == 0U)
+                  IDAT_len = 12U; /* Output another 0 length IDAT */
+
+               else
+               {
+                  /* End of IDATs, skip the CRC to make the code above load the
+                   * next chunk header next time round.
+                   */
+                  png_byte buffer[4];
+
+                  store_read_imp(ps, buffer, 4U);
+                  chunkpos += 4U;
+                  ps->IDAT_pos = IDAT_pos;
+                  ps->IDAT_len = IDAT_len;
+                  ps->IDAT_size = 0U;
+                  continue; /* Read the next chunk */
+               }
+            }
+
+            else
+            {
+               /* Middle of IDATs, use 'random' to determine the number of bits
+                * to use in the IDAT length.
+                */
+               IDAT_len = random_u32();
+               IDAT_len &= (1U << (1U + random % ps->IDAT_bits)) - 1U;
+               if (IDAT_len > IDAT_size)
+                  IDAT_len = IDAT_size;
+               IDAT_len += 12U; /* zero bytes may occur */
+            }
+
+            IDAT_pos = 0U;
+            ps->IDAT_crc = 0x35af061e; /* Ie: crc32(0UL, "IDAT", 4) */
+         } /* IDAT_pos == IDAT_len */
+
+         if (IDAT_pos < 8U) /* Return the header */ do
+         {
+            png_uint_32 b;
+            unsigned int shift;
+
+            if (IDAT_pos < 4U)
+               b = IDAT_len - 12U;
+
+            else
+               b = CHUNK_IDAT;
+
+            shift = 3U & IDAT_pos;
+            ++IDAT_pos;
+
+            if (shift < 3U)
+               b >>= 8U*(3U-shift);
+
+            *pb++ = 0xffU & b;
+         }
+         while (--st > 0 && IDAT_pos < 8);
+
+         else if (IDAT_pos < IDAT_len - 4U) /* I.e not the CRC */
+         {
+            if (chunkpos < chunklen-4U)
+            {
+               uInt avail = (uInt)-1;
+
+               if (avail > (IDAT_len-4U) - IDAT_pos)
+                  avail = (uInt)/*SAFE*/((IDAT_len-4U) - IDAT_pos);
+
+               if (avail > st)
+                  avail = (uInt)/*SAFE*/st;
+
+               if (avail > (chunklen-4U) - chunkpos)
+                  avail = (uInt)/*SAFE*/((chunklen-4U) - chunkpos);
+
+               store_read_imp(ps, pb, avail);
+               ps->IDAT_crc = crc32(ps->IDAT_crc, pb, avail);
+               pb += (png_size_t)/*SAFE*/avail;
+               st -= (png_size_t)/*SAFE*/avail;
+               chunkpos += (png_uint_32)/*SAFE*/avail;
+               IDAT_size -= (png_uint_32)/*SAFE*/avail;
+               IDAT_pos += (png_uint_32)/*SAFE*/avail;
+            }
+
+            else /* skip the input CRC */
+            {
+               png_byte buffer[4];
+
+               store_read_imp(ps, buffer, 4U);
+               chunkpos += 4U;
+            }
+         }
+
+         else /* IDAT crc */ do
+         {
+            uLong b = ps->IDAT_crc;
+            unsigned int shift = (IDAT_len - IDAT_pos); /* 4..1 */
+            ++IDAT_pos;
+
+            if (shift > 1U)
+               b >>= 8U*(shift-1U);
+
+            *pb++ = 0xffU & b;
+         }
+         while (--st > 0 && IDAT_pos < IDAT_len);
+
+         ps->IDAT_pos = IDAT_pos;
+         ps->IDAT_len = IDAT_len;
+         ps->IDAT_size = IDAT_size;
+      }
+
+      else /* !IDAT */
+      {
+         /* If there is still some pending IDAT data after the IDAT chunks have
+          * been processed there is a problem:
+          */
+         if (ps->IDAT_len > 0 && ps->IDAT_size > 0)
+            png_error(ps->pread, "internal: missing IDAT data");
+
+         if (chunktype == CHUNK_IEND && ps->IDAT_len == 0U)
+            png_error(ps->pread, "internal: missing IDAT");
+
+         if (chunkpos < 8U) /* Return the header */ do
+         {
+            png_uint_32 b;
+            unsigned int shift;
+
+            if (chunkpos < 4U)
+               b = chunklen - 12U;
+
+            else
+               b = chunktype;
+
+            shift = 3U & chunkpos;
+            ++chunkpos;
+
+            if (shift < 3U)
+               b >>= 8U*(3U-shift);
+
+            *pb++ = 0xffU & b;
+         }
+         while (--st > 0 && chunkpos < 8);
+
+         else /* Return chunk bytes, including the CRC */
+         {
+            png_size_t avail = st;
+
+            if (avail > chunklen - chunkpos)
+               avail = (png_size_t)/*SAFE*/(chunklen - chunkpos);
+
+            store_read_imp(ps, pb, avail);
+            pb += avail;
+            st -= avail;
+            chunkpos += (png_uint_32)/*SAFE*/avail;
+
+            /* Check for end of chunk and end-of-file; don't try to read a new
+             * chunk header at this point unless instructed to do so by 'min'.
+             */
+            if (chunkpos >= chunklen && max-st >= min &&
+                     store_read_buffer_avail(ps) == 0)
+               break;
+         }
+      } /* !IDAT */
+   }
+   while (st > 0);
+
+   ps->chunklen = chunklen;
+   ps->chunktype = chunktype;
+   ps->chunkpos = chunkpos;
+
+   return st; /* space left */
+}
+
 static void PNGCBAPI
 store_read(png_structp ppIn, png_bytep pb, png_size_t st)
 {
@@ -1340,26 +1707,33 @@ store_read(png_structp ppIn, png_bytep pb, png_size_t st)
    if (ps == NULL || ps->pread != pp)
       png_error(pp, "bad store read call");
 
-   store_read_imp(ps, pb, st);
+   store_read_chunk(ps, pb, st, st);
 }
 
 static void
 store_progressive_read(png_store *ps, png_structp pp, png_infop pi)
 {
-   /* Notice that a call to store_read will cause this function to fail because
-    * readpos will be set.
-    */
    if (ps->pread != pp || ps->current == NULL || ps->next == NULL)
       png_error(pp, "store state damaged (progressive)");
 
-   do
+   /* This is another Horowitz and Hill random noise generator.  In this case
+    * the aim is to stress the progressive reader with truly horrible variable
+    * buffer sizes in the range 1..500, so a sequence of 9 bit random numbers
+    * is generated.  We could probably just count from 1 to 32767 and get as
+    * good a result.
+    */
+   while (store_read_buffer_avail(ps) > 0)
    {
-      if (ps->readpos != 0)
-         png_error(pp, "store_read called during progressive read");
+      static png_uint_32 noise = 2;
+      png_size_t cb;
+      png_byte buffer[512];
 
-      png_process_data(pp, pi, ps->next->buffer, store_read_buffer_size(ps));
+      /* Generate 15 more bits of stuff: */
+      noise = (noise << 9) | ((noise ^ (noise >> (9-5))) & 0x1ff);
+      cb = noise & 0x1ff;
+      cb -= store_read_chunk(ps, buffer, cb, 1);
+      png_process_data(pp, pi, buffer, cb);
    }
-   while (store_read_buffer_next(ps));
 }
 #endif /* PNG_READ_SUPPORTED */
 
@@ -1730,6 +2104,11 @@ store_read_reset(png_store *ps)
    ps->next = NULL;
    ps->readpos = 0;
    ps->validated = 0;
+
+   ps->chunkpos = 8;
+   ps->chunktype = 0;
+   ps->chunklen = 16;
+   ps->IDAT_size = 0;
 }
 
 #ifdef PNG_READ_SUPPORTED
@@ -1744,6 +2123,11 @@ store_read_set(png_store *ps, png_uint_32 id)
       {
          ps->current = pf;
          ps->next = NULL;
+         ps->IDAT_size = pf->IDAT_size;
+         ps->IDAT_bits = pf->IDAT_bits; /* just a cache */
+         ps->IDAT_len = 0;
+         ps->IDAT_pos = 0;
+         ps->IDAT_crc = 0UL;
          store_read_buffer_next(ps);
          return;
       }
@@ -2581,17 +2965,6 @@ modifier_color_encoding_is_set(const png_modifier *pm)
    return pm->current_gamma != 0;
 }
 
-/* Convenience macros. */
-#define CHUNK(a,b,c,d) (((a)<<24)+((b)<<16)+((c)<<8)+(d))
-#define CHUNK_IHDR CHUNK(73,72,68,82)
-#define CHUNK_PLTE CHUNK(80,76,84,69)
-#define CHUNK_IDAT CHUNK(73,68,65,84)
-#define CHUNK_IEND CHUNK(73,69,78,68)
-#define CHUNK_cHRM CHUNK(99,72,82,77)
-#define CHUNK_gAMA CHUNK(103,65,77,65)
-#define CHUNK_sBIT CHUNK(115,66,73,84)
-#define CHUNK_sRGB CHUNK(115,82,71,66)
-
 /* The guts of modification are performed during a read. */
 static void
 modifier_crc(png_bytep buffer)
@@ -2631,7 +3004,7 @@ modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
       {
          static png_byte sign[8] = { 137, 80, 78, 71, 13, 10, 26, 10 };
          case modifier_start:
-            store_read_imp(&pm->this, pm->buffer, 8); /* size of signature. */
+            store_read_chunk(&pm->this, pm->buffer, 8, 8); /* signature. */
             pm->buffer_count = 8;
             pm->buffer_position = 0;
 
@@ -2641,7 +3014,7 @@ modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
             break;
 
          case modifier_signature:
-            store_read_imp(&pm->this, pm->buffer, 13+12); /* size of IHDR */
+            store_read_chunk(&pm->this, pm->buffer, 13+12, 13+12); /* IHDR */
             pm->buffer_count = 13+12;
             pm->buffer_position = 0;
 
@@ -2682,7 +3055,7 @@ modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
             {
                if (cb > st) cb = st;
                pm->flush -= cb;
-               store_read_imp(&pm->this, pb, cb);
+               store_read_chunk(&pm->this, pb, cb, cb);
                pb += cb;
                st -= cb;
                if (st == 0) return;
@@ -2699,7 +3072,7 @@ modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
                pm->pending_chunk = 0;
             }
             else
-               store_read_imp(&pm->this, pm->buffer, 8);
+               store_read_chunk(&pm->this, pm->buffer, 8, 8);
 
             pm->buffer_count = 8;
             pm->buffer_position = 0;
@@ -2765,8 +3138,8 @@ modifier_read_imp(png_modifier *pm, png_bytep pb, png_size_t st)
              */
             if (len+12 <= sizeof pm->buffer)
             {
-               store_read_imp(&pm->this, pm->buffer+pm->buffer_count,
-                   len+12-pm->buffer_count);
+               png_size_t s = len+12-pm->buffer_count;
+               store_read_chunk(&pm->this, pm->buffer+pm->buffer_count, s, s);
                pm->buffer_count = len+12;
 
                /* Check for a modification, else leave it be. */
@@ -3333,8 +3706,8 @@ set_random_tRNS(png_structp pp, png_infop pi, const png_byte colour_type,
    {
       if (bit_depth == 8)
       {
-         R16(tRNS.red);
-         R16(tRNS.green);
+         tRNS.red = random_u16();
+         tRNS.green = random_u16();
          tRNS.blue = tRNS.red ^ tRNS.green;
          tRNS.red &= mask;
          tRNS.green &= mask;
@@ -3343,7 +3716,7 @@ set_random_tRNS(png_structp pp, png_infop pi, const png_byte colour_type,
 
       else /* bit_depth == 16 */
       {
-         R16(tRNS.red);
+         tRNS.red = random_u16();
          tRNS.green = (png_uint_16)(tRNS.red * 257);
          tRNS.blue = (png_uint_16)(tRNS.green * 17);
       }
@@ -3351,7 +3724,7 @@ set_random_tRNS(png_structp pp, png_infop pi, const png_byte colour_type,
 
    else
    {
-      R16(tRNS.gray);
+      tRNS.gray = random_u16();
       tRNS.gray &= mask;
    }
 
@@ -7303,7 +7676,7 @@ image_transform_png_set_rgb_to_gray_ini(const image_transform *this,
       png_uint_32 ru;
       double total;
 
-      R32_1(ru);
+      ru = random_u32();
       data.green_coefficient = total = (ru & 0xffff) / 65535.;
       ru >>= 16;
       data.red_coefficient = (1 - total) * (ru & 0xffff) / 65535.;
@@ -8231,7 +8604,7 @@ image_transform_png_set_filler_set(const image_transform *this,
     * filler.  The 'filler' value has all 32 bits set, but only bit_depth
     * will be used.  At this point we don't know bit_depth.
     */
-   R32(data.filler);
+   data.filler = random_u32();
    data.flags = random_choice();
 
    png_set_filler(pp, data.filler, data.flags);
@@ -8304,7 +8677,7 @@ image_transform_png_set_add_alpha_set(const image_transform *this,
     * filler.  The 'filler' value has all 32 bits set, but only bit_depth
     * will be used.  At this point we don't know bit_depth.
     */
-   R32(data.filler);
+   data.filler = random_u32();
    data.flags = random_choice();
 
    png_set_add_alpha(pp, data.filler, data.flags);

contrib/libtests/timepng.c

@@ -2,7 +2,7 @@
  *
  * Copyright (c) 2013,2016 John Cunningham Bowler
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.22 [May 26, 2016]
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -44,8 +44,20 @@
 #  define voidcast(type, value) (value)
 #endif /* __cplusplus */
 
-#if ((defined(PNG_SEQUENTIAL_READ_SUPPORTED)) && defined(PNG_STDIO_SUPPORTED)\
-     && defined(PNG_EASY_ACCESS_SUPPORTED) && defined(PNG_INFO_IMAGE_SUPPORTED))
+/* 'CLOCK_PROCESS_CPUTIME_ID' is one of the clock timers for clock_gettime.  It
+ * need not be supported even when clock_gettime is available.  It returns the
+ * 'CPU' time the process has consumed.  'CPU' time is assumed to include time
+ * when the CPU is actually blocked by a pending cache fill but not time
+ * waiting for page faults.  The attempt is to get a measure of the actual time
+ * the implementation takes to read a PNG ignoring the potentially very large IO
+ * overhead.
+ */
+#if defined (CLOCK_PROCESS_CPUTIME_ID) && defined(PNG_STDIO_SUPPORTED) &&\
+    defined(PNG_EASY_ACCESS_SUPPORTED) &&\
+    (PNG_LIBPNG_VER >= 10700 ? defined(PNG_READ_PNG_SUPPORTED) :\
+     defined (PNG_SEQUENTIAL_READ_SUPPORTED) &&\
+     defined(PNG_INFO_IMAGE_SUPPORTED))
+
 typedef struct
 {
    FILE *input;

contrib/tools/reindent

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+# reindent inputabsize outputabsize inputcontinuestring outputcontinuestring
+# eg, to change libpng coding style from 3-space indentation to 4-space
+#
+#  reindent 3 4 " " "  " < example.c.orig > example.c
+#
+# Assumes that continued lines begin with indentation plus one space, and
+# that continued comments begin with indentation plus " *".
+
+unexpand --first-only --t $inputtabsize $1 | \
+   sed -e "/^	$3[^\*]/{s/	$3/	$4/}" | \
+   expand -t $2

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 1.6.15 [November 20, 2014]
- * Maintained 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Maintained 1998-2016 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
@@ -375,7 +375,7 @@ void read_png(FILE *fp, int sig_read)  /* File is already open */
     * low byte.
     */
 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-    png_set_scale_16(png_ptr);
+   png_set_scale_16(png_ptr);
 #else
    png_set_strip_16(png_ptr);
 #endif
@@ -530,7 +530,7 @@ void read_png(FILE *fp, int sig_read)  /* File is already open */
     * see the png_read_row() method below:
     */
    number_passes = png_set_interlace_handling(png_ptr);
-#else
+#else /* !READ_INTERLACING */
    number_passes = 1;
 #endif /* READ_INTERLACING */
 
@@ -988,11 +988,11 @@ void write_png(char *file_name /* , ... other image information ... */)
    png_bytep row_pointers[height];
 
    if (height > PNG_UINT_32_MAX/(sizeof (png_bytep)))
-     png_error (png_ptr, "Image is too tall to process in memory");
+      png_error (png_ptr, "Image is too tall to process in memory");
 
    /* Set up pointers into your "image" byte array */
    for (k = 0; k < height; k++)
-     row_pointers[k] = image + k*width*bytes_per_pixel;
+      row_pointers[k] = image + k*width*bytes_per_pixel;
 
    /* One of the following output methods is REQUIRED */
 

libpng-manual.txt

@@ -1,6 +1,6 @@
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.22rc01 - May 14, 2016
+ libpng version 1.6.24beta05 - July 13, 2016
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2016 Glenn Randers-Pehrson
@@ -11,7 +11,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.22rc01 - May 14, 2016
+ libpng versions 0.97, January 1998, through 1.6.24beta05 - July 13, 2016
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2016 Glenn Randers-Pehrson
 
@@ -559,7 +559,7 @@ non-interlaced case the row that was just handled is simply one less than the
 passed in row number, and pass will always be 0.  For the interlaced case the
 same applies unless the row value is 0, in which case the row just handled was
 the last one from one of the preceding passes.  Because interlacing may skip a
-pass you cannot be sure that the preceding pass is just 'pass-1', if you really
+pass you cannot be sure that the preceding pass is just 'pass-1'; if you really
 need to know what the last pass is record (row,pass) from the callback and use
 the last recorded value each time.
 
@@ -2230,7 +2230,8 @@ is exactly the same.  If you are planning on displaying the image
 after each pass, the "rectangle" effect is generally considered the
 better looking one.
 
-If you only want the "sparkle" effect, just call png_read_rows() as
+If you only want the "sparkle" effect, just call png_read_row() or
+png_read_rows() as
 normal, with the third parameter NULL.  Make sure you make pass over
 the image number_of_passes times, and you don't change the data in the
 rows between calls.  You can change the locations of the data, just
@@ -2239,6 +2240,8 @@ pass, and assumes the data from previous passes is still valid.
 
     png_read_rows(png_ptr, row_pointers, NULL,
         number_of_rows);
+    or
+    png_read_row(png_ptr, row_pointers, NULL);
 
 If you only want the first effect (the rectangles), do the same as
 before except pass the row buffer in the third parameter, and leave
@@ -2246,6 +2249,8 @@ the second parameter NULL.
 
     png_read_rows(png_ptr, NULL, row_pointers,
         number_of_rows);
+    or
+    png_read_row(png_ptr, NULL, row_pointers);
 
 If you don't want libpng to handle the interlacing details, just call
 png_read_rows() PNG_INTERLACE_ADAM7_PASSES times to read in all the images.
@@ -5345,7 +5350,7 @@ 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 1.6.22rc01 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.24beta05 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

libpng.3

@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "May 14, 2016"
+.TH LIBPNG 3 "July 13, 2016"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.22rc01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.24beta05
 .SH SYNOPSIS
 \fB
 #include <png.h>\fP
@@ -510,7 +510,7 @@ Following is a copy of the libpng-manual.txt file that accompanies libpng.
 .SH LIBPNG.TXT
 libpng-manual.txt - A description on how to use and modify libpng
 
- libpng version 1.6.22rc01 - May 14, 2016
+ libpng version 1.6.24beta05 - July 13, 2016
  Updated and distributed by Glenn Randers-Pehrson
  <glennrp at users.sourceforge.net>
  Copyright (c) 1998-2016 Glenn Randers-Pehrson
@@ -521,7 +521,7 @@ libpng-manual.txt - A description on how to use and modify libpng
 
  Based on:
 
- libpng versions 0.97, January 1998, through 1.6.22rc01 - May 14, 2016
+ libpng versions 0.97, January 1998, through 1.6.24beta05 - July 13, 2016
  Updated and distributed by Glenn Randers-Pehrson
  Copyright (c) 1998-2016 Glenn Randers-Pehrson
 
@@ -1069,7 +1069,7 @@ non-interlaced case the row that was just handled is simply one less than the
 passed in row number, and pass will always be 0.  For the interlaced case the
 same applies unless the row value is 0, in which case the row just handled was
 the last one from one of the preceding passes.  Because interlacing may skip a
-pass you cannot be sure that the preceding pass is just 'pass\-1', if you really
+pass you cannot be sure that the preceding pass is just 'pass\-1'; if you really
 need to know what the last pass is record (row,pass) from the callback and use
 the last recorded value each time.
 
@@ -2740,7 +2740,8 @@ is exactly the same.  If you are planning on displaying the image
 after each pass, the "rectangle" effect is generally considered the
 better looking one.
 
-If you only want the "sparkle" effect, just call png_read_rows() as
+If you only want the "sparkle" effect, just call png_read_row() or
+png_read_rows() as
 normal, with the third parameter NULL.  Make sure you make pass over
 the image number_of_passes times, and you don't change the data in the
 rows between calls.  You can change the locations of the data, just
@@ -2749,6 +2750,8 @@ pass, and assumes the data from previous passes is still valid.
 
     png_read_rows(png_ptr, row_pointers, NULL,
         number_of_rows);
+    or
+    png_read_row(png_ptr, row_pointers, NULL);
 
 If you only want the first effect (the rectangles), do the same as
 before except pass the row buffer in the third parameter, and leave
@@ -2756,6 +2759,8 @@ the second parameter NULL.
 
     png_read_rows(png_ptr, NULL, row_pointers,
         number_of_rows);
+    or
+    png_read_row(png_ptr, NULL, row_pointers);
 
 If you don't want libpng to handle the interlacing details, just call
 png_read_rows() PNG_INTERLACE_ADAM7_PASSES times to read in all the images.
@@ -5855,7 +5860,7 @@ 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 1.6.22rc01 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.24beta05 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
@@ -5955,9 +5960,9 @@ the first widely used release:
  ...
  1.2.56                  13    10256  12.so.0.56[.0]
  ...
- 1.5.25                  15    10525  15.so.15.25[.0]
+ 1.5.27                  15    10527  15.so.15.27[.0]
  ...
- 1.6.22                  16    10622  16.so.16.22[.0]
+ 1.6.24                  16    10624  16.so.16.24[.0]
 
 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -6013,7 +6018,7 @@ possible without all of you.
 
 Thanks to Frank J. T. Wojcik for helping with the documentation.
 
-Libpng version 1.6.22rc01 - May 14, 2016:
+Libpng version 1.6.24beta05 - July 13, 2016:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).
 
@@ -6038,7 +6043,7 @@ this sentence.
 
 This code is released under the libpng license.
 
-libpng versions 1.0.7, July 1, 2000 through 1.6.22rc01, May 14, 2016 are
+libpng versions 1.0.7, July 1, 2000 through 1.6.24beta05, July 13, 2016 are
 Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
 derived from libpng-1.0.6, and are distributed according to the same
 disclaimer and license as libpng-1.0.6 with the following individuals
@@ -6163,7 +6168,7 @@ files "pngbar.png" and "pngbar.jpg (88x31) and "pngnow.png" (98x31).
 
 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-May 14, 2016
+July 13, 2016
 
 .\" end of man page
 

libpngpf.3

@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "May 14, 2016"
+.TH LIBPNGPF 3 "July 13, 2016"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.22rc01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.24beta05
 (private functions)
 .SH SYNOPSIS
 \fB#include \fI"pngpriv.h"

png.5

@@ -1,4 +1,4 @@
-.TH PNG 5 "May 14, 2016"
+.TH PNG 5 "July 13, 2016"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
@@ -35,7 +35,7 @@ PNG 1.0 specification, October 1996:
 RFC 2083
 .IP
 .br
-ftp://ds.internic.net/rfc/rfc2083.txt
+http://www.ietf.org/rfc/rfc2083.txt
 .br
 or (as a W3C Recommendation) at
 .br

png.c

@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.6.19 [November 12, 2015]
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
  * Copyright (c) 1998-2002,2004,2006-2015 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.)
@@ -14,7 +14,7 @@
 #include "pngpriv.h"
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_22rc01 Your_png_h_is_not_version_1_6_22rc01;
+typedef png_libpng_version_1_6_24beta05 Your_png_h_is_not_version_1_6_24beta05;
 
 /* Tells libpng that we have already handled the first "num_bytes" bytes
  * of the PNG file signature.  If the PNG data is embedded into another
@@ -172,10 +172,10 @@ png_calculate_crc(png_structrp png_ptr, png_const_bytep ptr, png_size_t length)
 int
 png_user_version_check(png_structrp png_ptr, png_const_charp user_png_ver)
 {
-     /* Libpng versions 1.0.0 and later are binary compatible if the version
-      * string matches through the second '.'; we must recompile any
-      * applications that use any older library version.
-      */
+   /* Libpng versions 1.0.0 and later are binary compatible if the version
+    * string matches through the second '.'; we must recompile any
+    * applications that use any older library version.
+    */
 
    if (user_png_ver != NULL)
    {
@@ -775,14 +775,14 @@ png_get_copyright(png_const_structrp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.22rc01 - May 14, 2016" PNG_STRING_NEWLINE \
+      "libpng version 1.6.24beta05 - July 13, 2016" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson" \
       PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
       "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
       PNG_STRING_NEWLINE;
 #  else
-   return "libpng version 1.6.22rc01 - May 14, 2016\
+   return "libpng version 1.6.24beta05 - July 13, 2016\
       Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
@@ -2354,7 +2354,6 @@ png_compare_ICC_profile_with_sRGB(png_const_structrp png_ptr,
 
    return 0; /* no match */
 }
-#endif /* PNG_sRGB_PROFILE_CHECKS >= 0 */
 
 void /* PRIVATE */
 png_icc_set_sRGB(png_const_structrp png_ptr,
@@ -2363,12 +2362,11 @@ png_icc_set_sRGB(png_const_structrp png_ptr,
    /* Is this profile one of the known ICC sRGB profiles?  If it is, just set
     * the sRGB information.
     */
-#if PNG_sRGB_PROFILE_CHECKS >= 0
    if (png_compare_ICC_profile_with_sRGB(png_ptr, profile, adler) != 0)
-#endif
       (void)png_colorspace_set_sRGB(png_ptr, colorspace,
          (int)/*already checked*/png_get_uint_32(profile+64));
 }
+#endif /* PNG_sRGB_PROFILE_CHECKS >= 0 */
 #endif /* sRGB */
 
 int /* PRIVATE */
@@ -2385,7 +2383,7 @@ png_colorspace_set_ICC(png_const_structrp png_ptr, png_colorspacerp colorspace,
        png_icc_check_tag_table(png_ptr, colorspace, name, profile_length,
           profile) != 0)
    {
-#     ifdef PNG_sRGB_SUPPORTED
+#     if defined(PNG_sRGB_SUPPORTED) && PNG_sRGB_PROFILE_CHECKS >= 0
          /* If no sRGB support, don't try storing sRGB information */
          png_icc_set_sRGB(png_ptr, colorspace, profile, 0);
 #     endif
@@ -2470,7 +2468,7 @@ png_colorspace_set_rgb_coefficients(png_structrp png_ptr)
 static int /* PRIVATE */
 png_gt(size_t a, size_t b)
 {
-    return a > b;
+   return a > b;
 }
 #else
 #   define png_gt(a,b) ((a) > (b))
@@ -4088,131 +4086,133 @@ png_destroy_gamma_table(png_structrp png_ptr)
 void /* PRIVATE */
 png_build_gamma_table(png_structrp png_ptr, int bit_depth)
 {
-  png_debug(1, "in png_build_gamma_table");
+   png_debug(1, "in png_build_gamma_table");
 
-  /* Remove any existing table; this copes with multiple calls to
-   * png_read_update_info.  The warning is because building the gamma tables
-   * multiple times is a performance hit - it's harmless but the ability to call
-   * png_read_update_info() multiple times is new in 1.5.6 so it seems sensible
-   * to warn if the app introduces such a hit.
-   */
-  if (png_ptr->gamma_table != NULL || png_ptr->gamma_16_table != NULL)
-  {
-    png_warning(png_ptr, "gamma table being rebuilt");
-    png_destroy_gamma_table(png_ptr);
-  }
+   /* Remove any existing table; this copes with multiple calls to
+    * png_read_update_info. The warning is because building the gamma tables
+    * multiple times is a performance hit - it's harmless but the ability to
+    * call png_read_update_info() multiple times is new in 1.5.6 so it seems
+    * sensible to warn if the app introduces such a hit.
+    */
+   if (png_ptr->gamma_table != NULL || png_ptr->gamma_16_table != NULL)
+   {
+      png_warning(png_ptr, "gamma table being rebuilt");
+      png_destroy_gamma_table(png_ptr);
+   }
 
-  if (bit_depth <= 8)
-  {
-     png_build_8bit_table(png_ptr, &png_ptr->gamma_table,
-         png_ptr->screen_gamma > 0 ?  png_reciprocal2(png_ptr->colorspace.gamma,
-         png_ptr->screen_gamma) : PNG_FP_1);
+   if (bit_depth <= 8)
+   {
+      png_build_8bit_table(png_ptr, &png_ptr->gamma_table,
+          png_ptr->screen_gamma > 0 ?
+          png_reciprocal2(png_ptr->colorspace.gamma,
+          png_ptr->screen_gamma) : PNG_FP_1);
 
 #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
    defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-     if ((png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY)) != 0)
-     {
-        png_build_8bit_table(png_ptr, &png_ptr->gamma_to_1,
-            png_reciprocal(png_ptr->colorspace.gamma));
+      if ((png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY)) != 0)
+      {
+         png_build_8bit_table(png_ptr, &png_ptr->gamma_to_1,
+             png_reciprocal(png_ptr->colorspace.gamma));
 
-        png_build_8bit_table(png_ptr, &png_ptr->gamma_from_1,
-            png_ptr->screen_gamma > 0 ?  png_reciprocal(png_ptr->screen_gamma) :
-            png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
-     }
+         png_build_8bit_table(png_ptr, &png_ptr->gamma_from_1,
+             png_ptr->screen_gamma > 0 ?
+             png_reciprocal(png_ptr->screen_gamma) :
+             png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
+      }
 #endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-  }
+   }
 #ifdef PNG_16BIT_SUPPORTED
-  else
-  {
-     png_byte shift, sig_bit;
+   else
+   {
+      png_byte shift, sig_bit;
 
-     if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
-     {
-        sig_bit = png_ptr->sig_bit.red;
+      if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
+      {
+         sig_bit = png_ptr->sig_bit.red;
 
-        if (png_ptr->sig_bit.green > sig_bit)
-           sig_bit = png_ptr->sig_bit.green;
+         if (png_ptr->sig_bit.green > sig_bit)
+            sig_bit = png_ptr->sig_bit.green;
 
-        if (png_ptr->sig_bit.blue > sig_bit)
-           sig_bit = png_ptr->sig_bit.blue;
-     }
-     else
-        sig_bit = png_ptr->sig_bit.gray;
+         if (png_ptr->sig_bit.blue > sig_bit)
+            sig_bit = png_ptr->sig_bit.blue;
+      }
+      else
+         sig_bit = png_ptr->sig_bit.gray;
 
-     /* 16-bit gamma code uses this equation:
-      *
-      *   ov = table[(iv & 0xff) >> gamma_shift][iv >> 8]
-      *
-      * Where 'iv' is the input color value and 'ov' is the output value -
-      * pow(iv, gamma).
-      *
-      * Thus the gamma table consists of up to 256 256-entry tables.  The table
-      * is selected by the (8-gamma_shift) most significant of the low 8 bits of
-      * the color value then indexed by the upper 8 bits:
-      *
-      *   table[low bits][high 8 bits]
-      *
-      * So the table 'n' corresponds to all those 'iv' of:
-      *
-      *   <all high 8-bit values><n << gamma_shift>..<(n+1 << gamma_shift)-1>
-      *
-      */
-     if (sig_bit > 0 && sig_bit < 16U)
-        /* shift == insignificant bits */
-        shift = (png_byte)((16U - sig_bit) & 0xff);
+      /* 16-bit gamma code uses this equation:
+       *
+       *   ov = table[(iv & 0xff) >> gamma_shift][iv >> 8]
+       *
+       * Where 'iv' is the input color value and 'ov' is the output value -
+       * pow(iv, gamma).
+       *
+       * Thus the gamma table consists of up to 256 256-entry tables.  The table
+       * is selected by the (8-gamma_shift) most significant of the low 8 bits
+       * of the color value then indexed by the upper 8 bits:
+       *
+       *   table[low bits][high 8 bits]
+       *
+       * So the table 'n' corresponds to all those 'iv' of:
+       *
+       *   <all high 8-bit values><n << gamma_shift>..<(n+1 << gamma_shift)-1>
+       *
+       */
+      if (sig_bit > 0 && sig_bit < 16U)
+         /* shift == insignificant bits */
+         shift = (png_byte)((16U - sig_bit) & 0xff);
 
-     else
-        shift = 0; /* keep all 16 bits */
+      else
+         shift = 0; /* keep all 16 bits */
 
-     if ((png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8)) != 0)
-     {
-        /* PNG_MAX_GAMMA_8 is the number of bits to keep - effectively
-         * the significant bits in the *input* when the output will
-         * eventually be 8 bits.  By default it is 11.
-         */
-        if (shift < (16U - PNG_MAX_GAMMA_8))
-           shift = (16U - PNG_MAX_GAMMA_8);
-     }
+      if ((png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8)) != 0)
+      {
+         /* PNG_MAX_GAMMA_8 is the number of bits to keep - effectively
+          * the significant bits in the *input* when the output will
+          * eventually be 8 bits.  By default it is 11.
+          */
+         if (shift < (16U - PNG_MAX_GAMMA_8))
+            shift = (16U - PNG_MAX_GAMMA_8);
+      }
 
-     if (shift > 8U)
-        shift = 8U; /* Guarantees at least one table! */
+      if (shift > 8U)
+         shift = 8U; /* Guarantees at least one table! */
 
-     png_ptr->gamma_shift = shift;
+      png_ptr->gamma_shift = shift;
 
-     /* NOTE: prior to 1.5.4 this test used to include PNG_BACKGROUND (now
-      * PNG_COMPOSE).  This effectively smashed the background calculation for
-      * 16-bit output because the 8-bit table assumes the result will be reduced
-      * to 8 bits.
-      */
-     if ((png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8)) != 0)
-         png_build_16to8_table(png_ptr, &png_ptr->gamma_16_table, shift,
-         png_ptr->screen_gamma > 0 ? png_product2(png_ptr->colorspace.gamma,
-         png_ptr->screen_gamma) : PNG_FP_1);
+      /* NOTE: prior to 1.5.4 this test used to include PNG_BACKGROUND (now
+       * PNG_COMPOSE).  This effectively smashed the background calculation for
+       * 16-bit output because the 8-bit table assumes the result will be
+       * reduced to 8 bits.
+       */
+      if ((png_ptr->transformations & (PNG_16_TO_8 | PNG_SCALE_16_TO_8)) != 0)
+          png_build_16to8_table(png_ptr, &png_ptr->gamma_16_table, shift,
+          png_ptr->screen_gamma > 0 ? png_product2(png_ptr->colorspace.gamma,
+          png_ptr->screen_gamma) : PNG_FP_1);
 
-     else
-         png_build_16bit_table(png_ptr, &png_ptr->gamma_16_table, shift,
-         png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->colorspace.gamma,
-         png_ptr->screen_gamma) : PNG_FP_1);
+      else
+          png_build_16bit_table(png_ptr, &png_ptr->gamma_16_table, shift,
+          png_ptr->screen_gamma > 0 ? png_reciprocal2(png_ptr->colorspace.gamma,
+          png_ptr->screen_gamma) : PNG_FP_1);
 
 #if defined(PNG_READ_BACKGROUND_SUPPORTED) || \
    defined(PNG_READ_ALPHA_MODE_SUPPORTED) || \
    defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
-     if ((png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY)) != 0)
-     {
-        png_build_16bit_table(png_ptr, &png_ptr->gamma_16_to_1, shift,
-            png_reciprocal(png_ptr->colorspace.gamma));
+      if ((png_ptr->transformations & (PNG_COMPOSE | PNG_RGB_TO_GRAY)) != 0)
+      {
+         png_build_16bit_table(png_ptr, &png_ptr->gamma_16_to_1, shift,
+             png_reciprocal(png_ptr->colorspace.gamma));
 
-        /* Notice that the '16 from 1' table should be full precision, however
-         * the lookup on this table still uses gamma_shift, so it can't be.
-         * TODO: fix this.
-         */
-        png_build_16bit_table(png_ptr, &png_ptr->gamma_16_from_1, shift,
-            png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
-            png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
-     }
+         /* Notice that the '16 from 1' table should be full precision, however
+          * the lookup on this table still uses gamma_shift, so it can't be.
+          * TODO: fix this.
+          */
+         png_build_16bit_table(png_ptr, &png_ptr->gamma_16_from_1, shift,
+             png_ptr->screen_gamma > 0 ? png_reciprocal(png_ptr->screen_gamma) :
+             png_ptr->colorspace.gamma/* Probably doing rgb_to_gray */);
+      }
 #endif /* READ_BACKGROUND || READ_ALPHA_MODE || RGB_TO_GRAY */
-  }
+   }
 #endif /* 16BIT */
 }
 #endif /* READ_GAMMA */

png.h

@@ -1,7 +1,7 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.6.22rc01, May 14, 2016
+ * libpng version 1.6.24beta05, July 13, 2016
  *
  * Copyright (c) 1998-2002,2004,2006-2016 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
@@ -12,7 +12,7 @@
  * Authors and maintainers:
  *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
  *   libpng versions 0.89, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.6.22rc01, May 14, 2016:
+ *   libpng versions 0.97, January 1998, through 1.6.24beta05, July 13, 2016:
  *     Glenn Randers-Pehrson.
  *   See also "Contributing Authors", below.
  */
@@ -29,7 +29,7 @@
  * files that are distributed with libpng have other copyright owners and
  * are released under other open source licenses.
  *
- * libpng versions 1.0.7, July 1, 2000 through 1.6.22rc01, May 14, 2016 are
+ * libpng versions 1.0.7, July 1, 2000 through 1.6.24beta05, July 13, 2016 are
  * Copyright (c) 2000-2002, 2004, 2006-2016 Glenn Randers-Pehrson, are
  * derived from libpng-1.0.6, and are distributed according to the same
  * disclaimer and license as libpng-1.0.6 with the following individuals
@@ -215,9 +215,9 @@
  *    ...
  *    1.2.56                  13    10256  12.so.0.56[.0]
  *    ...
- *    1.5.25                  15    10525  15.so.15.25[.0]
+ *    1.5.27                  15    10527  15.so.15.27[.0]
  *    ...
- *    1.6.22                  16    10622  16.so.16.22[.0]
+ *    1.6.24                  16    10624  16.so.16.24[.0]
  *
  *    Henceforth the source version will match the shared-library major
  *    and minor numbers; the shared-library major version number will be
@@ -245,13 +245,13 @@
  * Y2K compliance in libpng:
  * =========================
  *
- *    May 14, 2016
+ *    July 13, 2016
  *
  *    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 1.6.22rc01 are Y2K compliant.  It is my belief that
+ *    upward through 1.6.24beta05 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
@@ -313,9 +313,8 @@
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.22rc01"
-#define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.6.22rc01 - May 14, 2016\n"
+#define PNG_LIBPNG_VER_STRING "1.6.24beta05"
+#define PNG_HEADER_VERSION_STRING " libpng version 1.6.24beta05 - July 13, 2016\n"
 
 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
@@ -323,13 +322,13 @@
 /* These should match the first 3 components of PNG_LIBPNG_VER_STRING: */
 #define PNG_LIBPNG_VER_MAJOR   1
 #define PNG_LIBPNG_VER_MINOR   6
-#define PNG_LIBPNG_VER_RELEASE 22
+#define PNG_LIBPNG_VER_RELEASE 24
 
 /* This should match the numeric part of the final component of
  * PNG_LIBPNG_VER_STRING, omitting any leading zero:
  */
 
-#define PNG_LIBPNG_VER_BUILD  01
+#define PNG_LIBPNG_VER_BUILD  05
 
 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -346,7 +345,7 @@
 #define PNG_LIBPNG_BUILD_SPECIAL 32 /* Cannot be OR'ed with
                                        PNG_LIBPNG_BUILD_PRIVATE */
 
-#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_RC
+#define PNG_LIBPNG_BUILD_BASE_TYPE PNG_LIBPNG_BUILD_BETA
 
 /* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
  * We must not include leading zeros.
@@ -354,20 +353,20 @@
  * version 1.0.0 was mis-numbered 100 instead of 10000).  From
  * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=release
  */
-#define PNG_LIBPNG_VER 10622 /* 1.6.22 */
+#define PNG_LIBPNG_VER 10624 /* 1.6.24 */
 
 /* Library configuration: these options cannot be changed after
  * the library has been built.
  */
 #ifndef PNGLCONF_H
-    /* If pnglibconf.h is missing, you can
-     * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
-     */
+/* If pnglibconf.h is missing, you can
+ * copy scripts/pnglibconf.h.prebuilt to pnglibconf.h
+ */
 #   include "pnglibconf.h"
 #endif
 
 #ifndef PNG_VERSION_INFO_ONLY
-   /* Machine specific configuration. */
+/* Machine specific configuration. */
 #  include "pngconf.h"
 #endif
 
@@ -464,7 +463,7 @@ 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_6_22rc01;
+typedef char* png_libpng_version_1_6_24beta05;
 
 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
  *
@@ -657,17 +656,17 @@ typedef png_time * * png_timepp;
  */
 typedef struct png_unknown_chunk_t
 {
-    png_byte name[5]; /* Textual chunk name with '\0' terminator */
-    png_byte *data;   /* Data, should not be modified on read! */
-    png_size_t size;
+   png_byte name[5]; /* Textual chunk name with '\0' terminator */
+   png_byte *data;   /* Data, should not be modified on read! */
+   png_size_t size;
 
-    /* On write 'location' must be set using the flag values listed below.
-     * Notice that on read it is set by libpng however the values stored have
-     * more bits set than are listed below.  Always treat the value as a
-     * bitmask.  On write set only one bit - setting multiple bits may cause the
-     * chunk to be written in multiple places.
-     */
-    png_byte location; /* mode of operation at read time */
+   /* On write 'location' must be set using the flag values listed below.
+    * Notice that on read it is set by libpng however the values stored have
+    * more bits set than are listed below.  Always treat the value as a
+    * bitmask.  On write set only one bit - setting multiple bits may cause the
+    * chunk to be written in multiple places.
+    */
+   png_byte location; /* mode of operation at read time */
 }
 png_unknown_chunk;
 
@@ -2300,8 +2299,10 @@ PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
  *    except for the IHDR, PLTE, tRNS, IDAT, and IEND chunks (which continue to
  *    be processed by libpng.
  */
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
 PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr,
     int keep, png_const_bytep chunk_list, int num_chunks));
+#endif /* HANDLE_AS_UNKNOWN */
 
 /* The "keep" PNG_HANDLE_CHUNK_ parameter for the specified chunk is returned;
  * the result is therefore true (non-zero) if special handling is required,
@@ -2309,7 +2310,7 @@ PNG_EXPORT(172, void, png_set_keep_unknown_chunks, (png_structrp png_ptr,
  */
 PNG_EXPORT(173, int, png_handle_as_unknown, (png_const_structrp png_ptr,
     png_const_bytep chunk_name));
-#endif
+#endif /* SET_UNKNOWN_CHUNKS */
 
 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 PNG_EXPORT(174, void, png_set_unknown_chunks, (png_const_structrp png_ptr,
@@ -2530,33 +2531,37 @@ PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
 
  /* fg and bg should be in `gamma 1.0' space; alpha is the opacity */
 
-#  define png_composite(composite, fg, alpha, bg)         \
-     { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \
-           * (png_uint_16)(alpha)                         \
-           + (png_uint_16)(bg)*(png_uint_16)(255          \
-           - (png_uint_16)(alpha)) + 128);                \
-       (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); }
+#  define png_composite(composite, fg, alpha, bg)        \
+   {                                                     \
+      png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) \
+          * (png_uint_16)(alpha)                         \
+          + (png_uint_16)(bg)*(png_uint_16)(255          \
+          - (png_uint_16)(alpha)) + 128);                \
+      (composite) = (png_byte)(((temp + (temp >> 8)) >> 8) & 0xff); \
+   }
 
-#  define png_composite_16(composite, fg, alpha, bg)       \
-     { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg)  \
-           * (png_uint_32)(alpha)                          \
-           + (png_uint_32)(bg)*(65535                      \
-           - (png_uint_32)(alpha)) + 32768);               \
-       (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); }
+#  define png_composite_16(composite, fg, alpha, bg)     \
+   {                                                     \
+      png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) \
+          * (png_uint_32)(alpha)                         \
+          + (png_uint_32)(bg)*(65535                     \
+          - (png_uint_32)(alpha)) + 32768);              \
+      (composite) = (png_uint_16)(0xffff & ((temp + (temp >> 16)) >> 16)); \
+   }
 
 #else  /* Standard method using integer division */
 
-#  define png_composite(composite, fg, alpha, bg)                        \
-     (composite) =                                                       \
-         (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
-         (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
-         127) / 255))
+#  define png_composite(composite, fg, alpha, bg)                      \
+   (composite) =                                                       \
+       (png_byte)(0xff & (((png_uint_16)(fg) * (png_uint_16)(alpha) +  \
+       (png_uint_16)(bg) * (png_uint_16)(255 - (png_uint_16)(alpha)) + \
+       127) / 255))
 
-#  define png_composite_16(composite, fg, alpha, bg)                         \
-     (composite) =                                                           \
-         (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \
-         (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +     \
-         32767) / 65535))
+#  define png_composite_16(composite, fg, alpha, bg)                       \
+   (composite) =                                                           \
+       (png_uint_16)(0xffff & (((png_uint_32)(fg) * (png_uint_32)(alpha) + \
+       (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +     \
+       32767) / 65535))
 #endif /* READ_COMPOSITE_NODIV */
 
 #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
@@ -2592,38 +2597,38 @@ PNG_EXPORT(207, void, png_save_uint_16, (png_bytep buf, unsigned int i));
  * format for negative values, which is almost certainly true.
  */
 #  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_uint_32)(*(buf)) << 24) + \
+    ((png_uint_32)(*((buf) + 1)) << 16) + \
+    ((png_uint_32)(*((buf) + 2)) << 8) + \
+    ((png_uint_32)(*((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)))))
+   ((png_uint_16) \
+    (((unsigned int)(*(buf)) << 8) + \
+    ((unsigned int)(*((buf) + 1)))))
 
 #  define PNG_get_int_32(buf) \
-     ((png_int_32)((*(buf) & 0x80) \
-      ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \
-      : (png_int_32)png_get_uint_32(buf)))
+   ((png_int_32)((*(buf) & 0x80) \
+    ? -((png_int_32)(((png_get_uint_32(buf)^0xffffffffU)+1U)&0x7fffffffU)) \
+    : (png_int_32)png_get_uint_32(buf)))
 
-   /* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h,
-    * but defining a macro name prefixed with PNG_PREFIX.
-    */
+/* If PNG_PREFIX is defined the same thing as below happens in pnglibconf.h,
+ * but defining a macro name prefixed with PNG_PREFIX.
+ */
 #  ifndef PNG_PREFIX
-#     define png_get_uint_32(buf) PNG_get_uint_32(buf)
-#     define png_get_uint_16(buf) PNG_get_uint_16(buf)
-#     define png_get_int_32(buf)  PNG_get_int_32(buf)
+#    define png_get_uint_32(buf) PNG_get_uint_32(buf)
+#    define png_get_uint_16(buf) PNG_get_uint_16(buf)
+#    define png_get_int_32(buf)  PNG_get_int_32(buf)
 #  endif
 #else
 #  ifdef PNG_PREFIX
-      /* No macros; revert to the (redefined) function */
-#     define PNG_get_uint_32 (png_get_uint_32)
-#     define PNG_get_uint_16 (png_get_uint_16)
-#     define PNG_get_int_32  (png_get_int_32)
+   /* No macros; revert to the (redefined) function */
+#    define PNG_get_uint_32 (png_get_uint_32)
+#    define PNG_get_uint_16 (png_get_uint_16)
+#    define PNG_get_int_32  (png_get_int_32)
 #  endif
 #endif
 
@@ -3171,9 +3176,9 @@ PNG_EXPORT(245, int, png_image_write_to_memory, (png_imagep image, void *memory,
 #define PNG_IMAGE_PNG_SIZE_MAX_(image, image_size)\
    ((8U/*sig*/+25U/*IHDR*/+16U/*gAMA*/+44U/*cHRM*/+12U/*IEND*/+\
     (((image).format&PNG_FORMAT_FLAG_COLORMAP)?/*colormap: PLTE, tRNS*/\
-     12U+3U*(image).colormap_entries/*PLTE data*/+\
-     (((image).format&PNG_FORMAT_FLAG_ALPHA)?\
-      12U/*tRNS*/+(image).colormap_entries:0U):0U)+\
+    12U+3U*(image).colormap_entries/*PLTE data*/+\
+    (((image).format&PNG_FORMAT_FLAG_ALPHA)?\
+    12U/*tRNS*/+(image).colormap_entries:0U):0U)+\
     12U)+(12U*((image_size)/PNG_ZBUF_SIZE))/*IDAT*/+(image_size))
    /* A helper for the following macro; if your compiler cannot handle the
     * following macro use this one with the result of

pngconf.h

@@ -1,9 +1,9 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng version 1.6.22rc01, May 14, 2016
+ * libpng version 1.6.24beta05, July 13, 2016
  *
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -188,27 +188,27 @@
    * compatible with GCC or Visual C because of different calling conventions.
    */
 #  if PNG_API_RULE == 2
-    /* If this line results in an error, either because __watcall is not
-     * understood or because of a redefine just below you cannot use *this*
-     * build of the library with the compiler you are using.  *This* build was
-     * build using Watcom and applications must also be built using Watcom!
-     */
+   /* If this line results in an error, either because __watcall is not
+    * understood or because of a redefine just below you cannot use *this*
+    * build of the library with the compiler you are using.  *This* build was
+    * build using Watcom and applications must also be built using Watcom!
+    */
 #    define PNGCAPI __watcall
 #  endif
 
 #  if defined(__GNUC__) || (defined(_MSC_VER) && (_MSC_VER >= 800))
 #    define PNGCAPI __cdecl
 #    if PNG_API_RULE == 1
-       /* If this line results in an error __stdcall is not understood and
-        * PNG_API_RULE should not have been set to '1'.
-        */
+   /* If this line results in an error __stdcall is not understood and
+    * PNG_API_RULE should not have been set to '1'.
+    */
 #      define PNGAPI __stdcall
 #    endif
 #  else
-    /* An older compiler, or one not detected (erroneously) above,
-     * if necessary override on the command line to get the correct
-     * variants for the compiler.
-     */
+   /* An older compiler, or one not detected (erroneously) above,
+    * if necessary override on the command line to get the correct
+    * variants for the compiler.
+    */
 #    ifndef PNGCAPI
 #      define PNGCAPI _cdecl
 #    endif
@@ -225,10 +225,10 @@
 
 #  if (defined(_MSC_VER) && _MSC_VER < 800) ||\
       (defined(__BORLANDC__) && __BORLANDC__ < 0x500)
-    /* older Borland and MSC
-     * compilers used '__export' and required this to be after
-     * the type.
-     */
+   /* older Borland and MSC
+    * compilers used '__export' and required this to be after
+    * the type.
+    */
 #    ifndef PNG_EXPORT_TYPE
 #      define PNG_EXPORT_TYPE(type) type PNG_IMPEXP
 #    endif
@@ -244,9 +244,9 @@
 #  if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__)
 #    define PNGAPI _System
 #  else /* !Windows/x86 && !OS/2 */
-    /* Use the defaults, or define PNG*API on the command line (but
-     * this will have to be done for every compile!)
-     */
+   /* Use the defaults, or define PNG*API on the command line (but
+    * this will have to be done for every compile!)
+    */
 #  endif /* other system, !OS/2 */
 #endif /* !Windows/x86 */
 
@@ -267,7 +267,7 @@
  */
 #ifndef PNG_IMPEXP
 #  if defined(PNG_USE_DLL) && defined(PNG_DLL_IMPORT)
-     /* This forces use of a DLL, disallowing static linking */
+   /* This forces use of a DLL, disallowing static linking */
 #    define PNG_IMPEXP PNG_DLL_IMPORT
 #  endif
 
@@ -340,7 +340,7 @@
    * less efficient code.
    */
 #  if defined(__clang__) && defined(__has_attribute)
-     /* Clang defines both __clang__ and __GNUC__. Check __clang__ first. */
+   /* 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

pngerror.c

@@ -1,8 +1,8 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * Last changed in libpng 1.6.15 [November 20, 2014]
- * Copyright (c) 1998-2002,2004,2006-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -44,7 +44,7 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
    if (png_ptr != NULL)
    {
       if ((png_ptr->flags &
-         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0
+         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0)
       {
          if (*error_message == PNG_LITERAL_SHARP)
          {
@@ -65,18 +65,18 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
 
             else
                error_message += offset;
-      }
-
-      else
-      {
-         if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0)
-         {
-            msg[0] = '0';
-            msg[1] = '\0';
-            error_message = msg;
          }
-       }
-     }
+
+         else
+         {
+            if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0)
+            {
+               msg[0] = '0';
+               msg[1] = '\0';
+               error_message = msg;
+            }
+         }
+      }
    }
 #endif
    if (png_ptr != NULL && png_ptr->error_fn != NULL)
@@ -391,10 +391,10 @@ png_benign_error(png_const_structrp png_ptr, png_const_charp error_message)
 void /* PRIVATE */
 png_app_warning(png_const_structrp png_ptr, png_const_charp error_message)
 {
-  if ((png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN) != 0)
-     png_warning(png_ptr, error_message);
-  else
-     png_error(png_ptr, error_message);
+   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)
@@ -404,10 +404,10 @@ png_app_warning(png_const_structrp png_ptr, png_const_charp error_message)
 void /* PRIVATE */
 png_app_error(png_const_structrp png_ptr, png_const_charp error_message)
 {
-  if ((png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN) != 0)
-     png_warning(png_ptr, error_message);
-  else
-     png_error(png_ptr, error_message);
+   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)

pngpread.c

@@ -1,8 +1,8 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.23 [June 9, 2016]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -210,12 +210,14 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
           (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) == 0)
-         if (png_ptr->push_length == 0)
-            return;
+      if ((png_ptr->mode & PNG_HAVE_IDAT) != 0)
+         if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
+            if (png_ptr->push_length == 0)
+               return;
+
+      png_ptr->mode |= PNG_HAVE_IDAT;
 
       if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
          png_benign_error(png_ptr, "Too many IDATs found");
@@ -499,7 +501,10 @@ png_push_save_buffer(png_structrp png_ptr)
          png_error(png_ptr, "Insufficient memory for save_buffer");
       }
 
-      memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+      if (old_buffer)
+         memcpy(png_ptr->save_buffer, old_buffer, png_ptr->save_buffer_size);
+      else if (png_ptr->save_buffer_size)
+         png_error(png_ptr, "save_buffer error");
       png_free(png_ptr, old_buffer);
       png_ptr->save_buffer_max = new_max;
    }

pngpriv.h

@@ -1,8 +1,8 @@
 
 /* pngpriv.h - private declarations for use inside libpng
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -420,10 +420,10 @@
 
 #  if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
     defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
-     /* We need to check that <math.h> hasn't already been included earlier
-      * as it seems it doesn't agree with <fp.h>, yet we should really use
-      * <fp.h> if possible.
-      */
+   /* We need to check that <math.h> hasn't already been included earlier
+    * as it seems it doesn't agree with <fp.h>, yet we should really use
+    * <fp.h> if possible.
+    */
 #    if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
 #      include <fp.h>
 #    endif
@@ -431,9 +431,9 @@
 #    include <math.h>
 #  endif
 #  if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
-     /* Amiga SAS/C: We must include builtin FPU functions when compiling using
-      * MATH=68881
-      */
+   /* Amiga SAS/C: We must include builtin FPU functions when compiling using
+    * MATH=68881
+    */
 #    include <m68881.h>
 #  endif
 #endif
@@ -1025,7 +1025,7 @@ PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
 #ifdef PNG_WRITE_cHRM_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
     const png_xy *xy), PNG_EMPTY);
-    /* The xy value must have been previously validated */
+   /* The xy value must have been previously validated */
 #endif
 
 #ifdef PNG_WRITE_sRGB_SUPPORTED
@@ -1413,7 +1413,7 @@ PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
 PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
    png_inforp info_ptr),PNG_EMPTY);
 PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
-     png_bytep row),PNG_EMPTY);
+    png_bytep row),PNG_EMPTY);
 PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
     png_inforp info_ptr),PNG_EMPTY);
 PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
@@ -1452,13 +1452,13 @@ PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
 
 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
     png_inforp info_ptr), PNG_EMPTY);
-    /* Synchronize the info 'valid' flags with the colorspace */
+   /* Synchronize the info 'valid' flags with the colorspace */
 
 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
     png_inforp info_ptr), PNG_EMPTY);
-    /* Copy the png_struct colorspace to the info_struct and call the above to
-     * synchronize the flags.  Checks for NULL info_ptr and does nothing.
-     */
+   /* Copy the png_struct colorspace to the info_struct and call the above to
+    * synchronize the flags.  Checks for NULL info_ptr and does nothing.
+    */
 #endif
 
 /* Added at libpng version 1.4.0 */
@@ -1915,8 +1915,6 @@ PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
     */
 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
    (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
-   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
 #endif
 
 PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,

pngread.c

@@ -1,8 +1,8 @@
 
 /* pngread.c - read a PNG file
  *
- * Last changed in libpng 1.6.17 [March 26, 2015]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -127,7 +127,10 @@ png_read_info(png_structrp png_ptr, png_inforp info_ptr)
       }
 
       else if ((png_ptr->mode & PNG_HAVE_IDAT) != 0)
+      {
+         png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
          png_ptr->mode |= PNG_AFTER_IDAT;
+      }
 
       /* This should be a binary subdivision search or a hash for
        * matching the chunk name rather than a linear search.
@@ -776,8 +779,8 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
 #ifdef PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED
    /* Report invalid palette index; added at libng-1.5.10 */
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-      png_ptr->num_palette_max > png_ptr->num_palette)
-     png_benign_error(png_ptr, "Read palette index exceeding num_palette");
+       png_ptr->num_palette_max > png_ptr->num_palette)
+      png_benign_error(png_ptr, "Read palette index exceeding num_palette");
 #endif
 
    do
@@ -785,6 +788,9 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
       png_uint_32 length = png_read_chunk_header(png_ptr);
       png_uint_32 chunk_name = png_ptr->chunk_name;
 
+      if (chunk_name != png_IDAT)
+         png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;
+
       if (chunk_name == png_IEND)
          png_handle_IEND(png_ptr, info_ptr, length);
 
@@ -799,9 +805,9 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
       {
          if (chunk_name == png_IDAT)
          {
-            if ((length > 0) ||
-                (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
-               png_benign_error(png_ptr, "Too many IDATs found");
+            if ((length > 0 && !(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+                || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
+               png_benign_error(png_ptr, ".Too many IDATs found");
          }
          png_handle_unknown(png_ptr, info_ptr, length, keep);
          if (chunk_name == png_PLTE)
@@ -812,10 +818,14 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
       else if (chunk_name == png_IDAT)
       {
          /* Zero length IDATs are legal after the last IDAT has been
-          * read, but not after other chunks have been read.
+          * read, but not after other chunks have been read.  1.6 does not
+          * always read all the deflate data; specifically it cannot be relied
+          * upon to read the Adler32 at the end.  If it doesn't ignore IDAT
+          * chunks which are longer than zero as well:
           */
-         if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
-            png_benign_error(png_ptr, "Too many IDATs found");
+         if ((length > 0 && !(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+             || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
+            png_benign_error(png_ptr, "..Too many IDATs found");
 
          png_crc_finish(png_ptr, length);
       }
@@ -1619,7 +1629,7 @@ png_image_skip_unused_chunks(png_structrp png_ptr)
        /* But do not ignore image data handling chunks */
        png_set_keep_unknown_chunks(png_ptr, PNG_HANDLE_CHUNK_AS_DEFAULT,
          chunks_to_process, (int)/*SAFE*/(sizeof chunks_to_process)/5);
-    }
+   }
 }
 
 #  define PNG_SKIP_CHUNKS(p) png_image_skip_unused_chunks(p)
@@ -4077,6 +4087,12 @@ png_image_finish_read(png_imagep image, png_const_colorp background,
        */
       const unsigned int channels = PNG_IMAGE_PIXEL_CHANNELS(image->format);
 
+      /* The following checks just the 'row_stride' calculation to ensure it
+       * fits in a signed 32-bit value.  Because channels/components can be
+       * either 1 or 2 bytes in size the length of a row can still overflow 32
+       * bits; this is just to verify that the 'row_stride' argument can be
+       * represented.
+       */
       if (image->width <= 0x7FFFFFFFU/channels) /* no overflow */
       {
          png_uint_32 check;
@@ -4091,13 +4107,30 @@ png_image_finish_read(png_imagep image, png_const_colorp background,
          else
             check = row_stride;
 
+         /* This verifies 'check', the absolute value of the actual stride
+          * passed in and detects overflow in the application calculation (i.e.
+          * if the app did actually pass in a non-zero 'row_stride'.
+          */
          if (image->opaque != NULL && buffer != NULL && check >= png_row_stride)
          {
             /* Now check for overflow of the image buffer calculation; this
              * limits the whole image size to 32 bits for API compatibility with
              * the current, 32-bit, PNG_IMAGE_BUFFER_SIZE macro.
+             *
+             * The PNG_IMAGE_BUFFER_SIZE macro is:
+             *
+             *    (PNG_IMAGE_PIXEL_COMPONENT_SIZE(fmt)*height*(row_stride))
+             *
+             * And the component size is always 1 or 2, so make sure that the
+             * number of *bytes* that the application is saying are available
+             * does actually fit into a 32-bit number.
+             *
+             * NOTE: this will be changed in 1.7 because PNG_IMAGE_BUFFER_SIZE
+             * will be changed to use png_alloc_size_t; bigger images can be
+             * accomodated on 64-bit systems.
              */
-            if (image->height <= 0xFFFFFFFF/png_row_stride)
+            if (image->height <=
+                0xFFFFFFFFU/PNG_IMAGE_PIXEL_COMPONENT_SIZE(image->format)/check)
             {
                if ((image->format & PNG_FORMAT_FLAG_COLORMAP) == 0 ||
                   (image->colormap_entries > 0 && colormap != NULL))

pngrtran.c

@@ -1,7 +1,7 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.22 [May 26, 2016]
  * Copyright (c) 1998-2002,2004,2006-2016 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.)

pngrutil.c

@@ -1,8 +1,8 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.6.20 [December 3, 2014]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -1512,12 +1512,12 @@ png_handle_iCCP(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
                                     png_crc_finish(png_ptr, length);
                                     finished = 1;
 
-#                                   ifdef PNG_sRGB_SUPPORTED
+# if defined(PNG_sRGB_SUPPORTED) && PNG_sRGB_PROFILE_CHECKS >= 0
                                     /* Check for a match against sRGB */
                                     png_icc_set_sRGB(png_ptr,
                                        &png_ptr->colorspace, profile,
                                        png_ptr->zstream.adler);
-#                                   endif
+# endif
 
                                     /* Steal the profile for info_ptr. */
                                     if (info_ptr != NULL)
@@ -2465,8 +2465,8 @@ png_handle_tEXt(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 
    if (buffer == NULL)
    {
-     png_chunk_benign_error(png_ptr, "out of memory");
-     return;
+      png_chunk_benign_error(png_ptr, "out of memory");
+      return;
    }
 
    png_crc_read(png_ptr, buffer, length);
@@ -4447,42 +4447,42 @@ defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
 
    if (row_bytes + 48 > png_ptr->old_big_row_buf_size)
    {
-     png_free(png_ptr, png_ptr->big_row_buf);
-     png_free(png_ptr, png_ptr->big_prev_row);
+      png_free(png_ptr, png_ptr->big_row_buf);
+      png_free(png_ptr, png_ptr->big_prev_row);
 
-     if (png_ptr->interlaced != 0)
-        png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr,
-            row_bytes + 48);
+      if (png_ptr->interlaced != 0)
+         png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr,
+             row_bytes + 48);
 
-     else
-        png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 48);
+      else
+         png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes + 48);
 
-     png_ptr->big_prev_row = (png_bytep)png_malloc(png_ptr, row_bytes + 48);
+      png_ptr->big_prev_row = (png_bytep)png_malloc(png_ptr, row_bytes + 48);
 
 #ifdef PNG_ALIGNED_MEMORY_SUPPORTED
-     /* Use 16-byte aligned memory for row_buf with at least 16 bytes
-      * of padding before and after row_buf; treat prev_row similarly.
-      * NOTE: the alignment is to the start of the pixels, one beyond the start
-      * of the buffer, because of the filter byte.  Prior to libpng 1.5.6 this
-      * was incorrect; the filter byte was aligned, which had the exact
-      * opposite effect of that intended.
-      */
-     {
-        png_bytep temp = png_ptr->big_row_buf + 32;
-        int extra = (int)((temp - (png_bytep)0) & 0x0f);
-        png_ptr->row_buf = temp - extra - 1/*filter byte*/;
+      /* Use 16-byte aligned memory for row_buf with at least 16 bytes
+       * of padding before and after row_buf; treat prev_row similarly.
+       * NOTE: the alignment is to the start of the pixels, one beyond the start
+       * of the buffer, because of the filter byte.  Prior to libpng 1.5.6 this
+       * was incorrect; the filter byte was aligned, which had the exact
+       * opposite effect of that intended.
+       */
+      {
+         png_bytep temp = png_ptr->big_row_buf + 32;
+         int extra = (int)((temp - (png_bytep)0) & 0x0f);
+         png_ptr->row_buf = temp - extra - 1/*filter byte*/;
 
-        temp = png_ptr->big_prev_row + 32;
-        extra = (int)((temp - (png_bytep)0) & 0x0f);
-        png_ptr->prev_row = temp - extra - 1/*filter byte*/;
-     }
+         temp = png_ptr->big_prev_row + 32;
+         extra = (int)((temp - (png_bytep)0) & 0x0f);
+         png_ptr->prev_row = temp - extra - 1/*filter byte*/;
+      }
 
 #else
-     /* Use 31 bytes of padding before and 17 bytes after row_buf. */
-     png_ptr->row_buf = png_ptr->big_row_buf + 31;
-     png_ptr->prev_row = png_ptr->big_prev_row + 31;
+      /* Use 31 bytes of padding before and 17 bytes after row_buf. */
+      png_ptr->row_buf = png_ptr->big_row_buf + 31;
+      png_ptr->prev_row = png_ptr->big_prev_row + 31;
 #endif
-     png_ptr->old_big_row_buf_size = row_bytes + 48;
+      png_ptr->old_big_row_buf_size = row_bytes + 48;
    }
 
 #ifdef PNG_MAX_MALLOC_64K

pngset.c

@@ -1,8 +1,8 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * Last changed in libpng 1.6.21 [January 15, 2016]
- * Copyright (c) 1998-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2016 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.)
  *
@@ -316,10 +316,10 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
 
    length = strlen(units) + 1;
    png_debug1(3, "allocating units for info (%lu bytes)",
-     (unsigned long)length);
+       (unsigned long)length);
 
    info_ptr->pcal_units = png_voidcast(png_charp,
-      png_malloc_warn(png_ptr, length));
+       png_malloc_warn(png_ptr, length));
 
    if (info_ptr->pcal_units == NULL)
    {
@@ -952,12 +952,14 @@ png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
 
        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
 
-       /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
-       png_ptr->trans_alpha = info_ptr->trans_alpha = png_voidcast(png_bytep,
-         png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
-
        if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
+       {
+         /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
+          info_ptr->trans_alpha = png_voidcast(png_bytep,
+             png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH));
           memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
+       }
+       png_ptr->trans_alpha = info_ptr->trans_alpha;
    }
 
    if (trans_color != NULL)
@@ -1500,60 +1502,60 @@ png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
 void PNGAPI
 png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
 {
-    if (png_ptr == NULL)
-       return;
+   if (png_ptr == NULL)
+      return;
 
-    if (size == 0 || size > PNG_UINT_31_MAX)
-       png_error(png_ptr, "invalid compression buffer size");
+   if (size == 0 || size > PNG_UINT_31_MAX)
+      png_error(png_ptr, "invalid compression buffer size");
 
 #  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
-      {
-         png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
-         return;
-      }
+   if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
+   {
+      png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
+      return;
+   }
 #  endif
 
 #  ifdef PNG_WRITE_SUPPORTED
-      if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
+   if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
+   {
+      if (png_ptr->zowner != 0)
       {
-         if (png_ptr->zowner != 0)
-         {
-            png_warning(png_ptr,
-              "Compression buffer size cannot be changed because it is in use");
+         png_warning(png_ptr,
+           "Compression buffer size cannot be changed because it is in use");
 
-            return;
-         }
+         return;
+      }
 
 #ifndef __COVERITY__
-         /* Some compilers complain that this is always false.  However, it
-          * can be true when integer overflow happens.
-          */
-         if (size > ZLIB_IO_MAX)
-         {
-            png_warning(png_ptr,
-               "Compression buffer size limited to system maximum");
-            size = ZLIB_IO_MAX; /* must fit */
-         }
+      /* Some compilers complain that this is always false.  However, it
+       * can be true when integer overflow happens.
+       */
+      if (size > ZLIB_IO_MAX)
+      {
+         png_warning(png_ptr,
+            "Compression buffer size limited to system maximum");
+         size = ZLIB_IO_MAX; /* must fit */
+      }
 #endif
 
-         if (size < 6)
-         {
-            /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
-             * if this is permitted.
-             */
-            png_warning(png_ptr,
-               "Compression buffer size cannot be reduced below 6");
+      if (size < 6)
+      {
+         /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH
+          * if this is permitted.
+          */
+         png_warning(png_ptr,
+            "Compression buffer size cannot be reduced below 6");
 
-            return;
-         }
-
-         if (png_ptr->zbuffer_size != size)
-         {
-            png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
-            png_ptr->zbuffer_size = (uInt)size;
-         }
+         return;
       }
+
+      if (png_ptr->zbuffer_size != size)
+      {
+         png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list);
+         png_ptr->zbuffer_size = (uInt)size;
+      }
+   }
 #  endif
 }
 
@@ -1660,7 +1662,9 @@ png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
 png_uint_32 /* PRIVATE */
 png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
 {
+#ifdef PNG_WARNINGS_SUPPORTED
    png_const_charp orig_key = key;
+#endif
    png_uint_32 key_len = 0;
    int bad_character = 0;
    int space = 1;
@@ -1723,7 +1727,9 @@ 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 */
+#else /* !WARNINGS */
+   PNG_UNUSED(png_ptr)
+#endif /* !WARNINGS */
 
    return key_len;
 }

pngstruct.h

@@ -1,8 +1,8 @@
 
 /* pngstruct.h - header file for PNG reference library
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -249,7 +249,7 @@ struct png_struct_def
    png_byte filter;           /* file filter type (always 0) */
    png_byte interlaced;       /* PNG_INTERLACE_NONE, PNG_INTERLACE_ADAM7 */
    png_byte pass;             /* current interlace pass (0 - 6) */
-   png_byte do_filter;        /* row filter flags (see PNG_FILTER_ below ) */
+   png_byte do_filter;        /* row filter flags (see PNG_FILTER_ in png.h ) */
    png_byte color_type;       /* color type of file */
    png_byte bit_depth;        /* bit depth of file */
    png_byte usr_bit_depth;    /* bit depth of users row: write only */

pngtest.c

@@ -1,8 +1,8 @@
 
 /* pngtest.c - a simple test program to test libpng
  *
- * Last changed in libpng 1.5.25 [December 3, 2015]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -139,13 +139,13 @@ static char tIME_string[PNG_tIME_STRING_LENGTH] = "tIME chunk is not present";
 static int
 tIME_to_str(png_structp png_ptr, png_charp ts, png_const_timep t)
 {
-    png_const_charp str = png_convert_to_rfc1123(png_ptr, t);
+   png_const_charp str = png_convert_to_rfc1123(png_ptr, t);
 
-    if (str == NULL)
-        return 0;
+   if (str == NULL)
+       return 0;
 
-    strcpy(ts, str);
-    return 1;
+   strcpy(ts, str);
+   return 1;
 }
 #endif /* older libpng */
 #endif
@@ -249,95 +249,95 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
     *  png_byte pixel_depth   bits per pixel (depth*channels)
     */
 
-    /* Counts the number of zero samples (or zero pixels if color_type is 3 */
+   /* Counts the number of zero samples (or zero pixels if color_type is 3 */
 
-    if (row_info->color_type == 0 || row_info->color_type == 3)
-    {
-       int pos = 0;
-       png_uint_32 n, nstop;
+   if (row_info->color_type == 0 || row_info->color_type == 3)
+   {
+      int pos = 0;
+      png_uint_32 n, nstop;
 
-       for (n = 0, nstop=row_info->width; n<nstop; n++)
-       {
-          if (row_info->bit_depth == 1)
-          {
-             if (((*dp << pos++ ) & 0x80) == 0)
-                zero_samples++;
+      for (n = 0, nstop=row_info->width; n<nstop; n++)
+      {
+         if (row_info->bit_depth == 1)
+         {
+            if (((*dp << pos++ ) & 0x80) == 0)
+               zero_samples++;
 
-             if (pos == 8)
-             {
-                pos = 0;
-                dp++;
-             }
-          }
+            if (pos == 8)
+            {
+               pos = 0;
+               dp++;
+            }
+         }
 
-          if (row_info->bit_depth == 2)
-          {
-             if (((*dp << (pos+=2)) & 0xc0) == 0)
-                zero_samples++;
+         if (row_info->bit_depth == 2)
+         {
+            if (((*dp << (pos+=2)) & 0xc0) == 0)
+               zero_samples++;
 
-             if (pos == 8)
-             {
-                pos = 0;
-                dp++;
-             }
-          }
+            if (pos == 8)
+            {
+               pos = 0;
+               dp++;
+            }
+         }
 
-          if (row_info->bit_depth == 4)
-          {
-             if (((*dp << (pos+=4)) & 0xf0) == 0)
-                zero_samples++;
+         if (row_info->bit_depth == 4)
+         {
+            if (((*dp << (pos+=4)) & 0xf0) == 0)
+               zero_samples++;
 
-             if (pos == 8)
-             {
-                pos = 0;
-                dp++;
-             }
-          }
+            if (pos == 8)
+            {
+               pos = 0;
+               dp++;
+            }
+         }
 
-          if (row_info->bit_depth == 8)
-             if (*dp++ == 0)
-                zero_samples++;
+         if (row_info->bit_depth == 8)
+            if (*dp++ == 0)
+               zero_samples++;
 
-          if (row_info->bit_depth == 16)
-          {
-             if ((*dp | *(dp+1)) == 0)
-                zero_samples++;
-             dp+=2;
-          }
-       }
-    }
-    else /* Other color types */
-    {
-       png_uint_32 n, nstop;
-       int channel;
-       int color_channels = row_info->channels;
-       if (row_info->color_type > 3)
-          color_channels--;
+         if (row_info->bit_depth == 16)
+         {
+            if ((*dp | *(dp+1)) == 0)
+               zero_samples++;
+            dp+=2;
+         }
+      }
+   }
+   else /* Other color types */
+   {
+      png_uint_32 n, nstop;
+      int channel;
+      int color_channels = row_info->channels;
+      if (row_info->color_type > 3)
+         color_channels--;
 
-       for (n = 0, nstop=row_info->width; n<nstop; n++)
-       {
-          for (channel = 0; channel < color_channels; channel++)
-          {
-             if (row_info->bit_depth == 8)
-                if (*dp++ == 0)
-                   zero_samples++;
+      for (n = 0, nstop=row_info->width; n<nstop; n++)
+      {
+         for (channel = 0; channel < color_channels; channel++)
+         {
+            if (row_info->bit_depth == 8)
+               if (*dp++ == 0)
+                  zero_samples++;
 
-             if (row_info->bit_depth == 16)
-             {
-                if ((*dp | *(dp+1)) == 0)
-                   zero_samples++;
+            if (row_info->bit_depth == 16)
+            {
+               if ((*dp | *(dp+1)) == 0)
+                  zero_samples++;
 
-                dp+=2;
-             }
-          }
-          if (row_info->color_type > 3)
-          {
-             dp++;
-             if (row_info->bit_depth == 16)
-                dp++;
-          }
-       }
-    }
+               dp+=2;
+            }
+         }
+         if (row_info->color_type > 3)
+         {
+            dp++;
+            if (row_info->bit_depth == 16)
+               dp++;
+         }
+      }
+   }
 }
 #endif /* WRITE_USER_TRANSFORM */
 
@@ -935,7 +935,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 #ifdef PNG_READ_USER_CHUNKS_SUPPORTED
    init_callback_info(read_info_ptr);
    png_set_read_user_chunk_fn(read_ptr, &user_chunk_data,
-     read_user_chunk_callback);
+       read_user_chunk_callback);
 #endif
 
 #ifdef PNG_SETJMP_SUPPORTED
@@ -1855,19 +1855,19 @@ main(int argc, char *argv[])
    }
 
    if (multiple == 0 && argc == 3 + verbose)
-     outname = argv[2 + verbose];
+      outname = argv[2 + verbose];
 
    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",
-        argv[0], argv[0]);
-     fprintf(STDERR,
-       "  reads/writes one PNG file (without -m) or multiple files (-m)\n");
-     fprintf(STDERR,
-       "  with -m %s is used as a temporary file\n", outname);
-     exit(1);
+      fprintf(STDERR,
+          "usage: %s [infile.png] [outfile.png]\n\t%s -m {infile.png}\n",
+          argv[0], argv[0]);
+      fprintf(STDERR,
+          "  reads/writes one PNG file (without -m) or multiple files (-m)\n");
+      fprintf(STDERR,
+          "  with -m %s is used as a temporary file\n", outname);
+      exit(1);
    }
 
    if (multiple != 0)
@@ -2079,4 +2079,4 @@ main(void)
 #endif
 
 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_22rc01 Your_png_h_is_not_version_1_6_22rc01;
+typedef png_libpng_version_1_6_24beta05 Your_png_h_is_not_version_1_6_24beta05;

pngwutil.c

@@ -1,8 +1,8 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * Last changed in libpng 1.6.22 [(PENDING RELEASE)]
- * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.24 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2002,2004,2006-2016 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.)
  *
@@ -2262,14 +2262,22 @@ png_setup_sub_row(png_structrp png_ptr, const png_uint_32 bpp,
         i++, rp++, dp++)
    {
       v = *dp = *rp;
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
    }
 
    for (lp = png_ptr->row_buf + 1; i < row_bytes;
       i++, rp++, lp++, dp++)
    {
       v = *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
 
       if (sum > lmins)  /* We are already worse, don't continue. */
         break;
@@ -2278,6 +2286,28 @@ png_setup_sub_row(png_structrp png_ptr, const png_uint_32 bpp,
    return (sum);
 }
 
+static void /* PRIVATE */
+png_setup_sub_row_only(png_structrp png_ptr, const png_uint_32 bpp,
+    const png_size_t row_bytes)
+{
+   png_bytep rp, dp, lp;
+   png_size_t i;
+
+   png_ptr->try_row[0] = PNG_FILTER_VALUE_SUB;
+
+   for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1; i < bpp;
+        i++, rp++, dp++)
+   {
+      *dp = *rp;
+   }
+
+   for (lp = png_ptr->row_buf + 1; i < row_bytes;
+      i++, rp++, lp++, dp++)
+   {
+      *dp = (png_byte)(((int)*rp - (int)*lp) & 0xff);
+   }
+}
+
 static png_size_t /* PRIVATE */
 png_setup_up_row(png_structrp png_ptr, const png_size_t row_bytes,
     const png_size_t lmins)
@@ -2294,7 +2324,11 @@ png_setup_up_row(png_structrp png_ptr, const png_size_t row_bytes,
        i++, rp++, pp++, dp++)
    {
       v = *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
 
       if (sum > lmins)  /* We are already worse, don't continue. */
         break;
@@ -2302,6 +2336,21 @@ png_setup_up_row(png_structrp png_ptr, const png_size_t row_bytes,
 
    return (sum);
 }
+static void /* PRIVATE */
+png_setup_up_row_only(png_structrp png_ptr, const png_size_t row_bytes)
+{
+   png_bytep rp, dp, pp;
+   png_size_t i;
+
+   png_ptr->try_row[0] = PNG_FILTER_VALUE_UP;
+
+   for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
+       pp = png_ptr->prev_row + 1; i < row_bytes;
+       i++, rp++, pp++, dp++)
+   {
+      *dp = (png_byte)(((int)*rp - (int)*pp) & 0xff);
+   }
+}
 
 static png_size_t /* PRIVATE */
 png_setup_avg_row(png_structrp png_ptr, const png_uint_32 bpp,
@@ -2319,7 +2368,11 @@ png_setup_avg_row(png_structrp png_ptr, const png_uint_32 bpp,
    {
       v = *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
 
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
    }
 
    for (lp = png_ptr->row_buf + 1; i < row_bytes; i++)
@@ -2327,7 +2380,11 @@ png_setup_avg_row(png_structrp png_ptr, const png_uint_32 bpp,
       v = *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
           & 0xff);
 
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
 
       if (sum > lmins)  /* We are already worse, don't continue. */
         break;
@@ -2335,6 +2392,27 @@ png_setup_avg_row(png_structrp png_ptr, const png_uint_32 bpp,
 
    return (sum);
 }
+static void /* PRIVATE */
+png_setup_avg_row_only(png_structrp png_ptr, const png_uint_32 bpp,
+      const png_size_t row_bytes)
+{
+   png_bytep rp, dp, pp, lp;
+   png_uint_32 i;
+
+   png_ptr->try_row[0] = PNG_FILTER_VALUE_AVG;
+
+   for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
+        pp = png_ptr->prev_row + 1; i < bpp; i++)
+   {
+      *dp++ = (png_byte)(((int)*rp++ - ((int)*pp++ / 2)) & 0xff);
+   }
+
+   for (lp = png_ptr->row_buf + 1; i < row_bytes; i++)
+   {
+      *dp++ = (png_byte)(((int)*rp++ - (((int)*pp++ + (int)*lp++) / 2))
+          & 0xff);
+   }
+}
 
 static png_size_t /* PRIVATE */
 png_setup_paeth_row(png_structrp png_ptr, const png_uint_32 bpp,
@@ -2352,7 +2430,11 @@ png_setup_paeth_row(png_structrp png_ptr, const png_uint_32 bpp,
    {
       v = *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
 
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
    }
 
    for (lp = png_ptr->row_buf + 1, cp = png_ptr->prev_row + 1; i < row_bytes;
@@ -2381,7 +2463,11 @@ png_setup_paeth_row(png_structrp png_ptr, const png_uint_32 bpp,
 
       v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
 
+#ifdef PNG_USE_ABS
+      sum += 128 - abs(v - 128);
+#else
       sum += (v < 128) ? v : 256 - v;
+#endif
 
       if (sum > lmins)  /* We are already worse, don't continue. */
         break;
@@ -2389,6 +2475,48 @@ png_setup_paeth_row(png_structrp png_ptr, const png_uint_32 bpp,
 
    return (sum);
 }
+static void /* PRIVATE */
+png_setup_paeth_row_only(png_structrp png_ptr, const png_uint_32 bpp,
+    const png_size_t row_bytes)
+{
+   png_bytep rp, dp, pp, cp, lp;
+   png_size_t i;
+
+   png_ptr->try_row[0] = PNG_FILTER_VALUE_PAETH;
+
+   for (i = 0, rp = png_ptr->row_buf + 1, dp = png_ptr->try_row + 1,
+       pp = png_ptr->prev_row + 1; i < bpp; i++)
+   {
+      *dp++ = (png_byte)(((int)*rp++ - (int)*pp++) & 0xff);
+   }
+
+   for (lp = png_ptr->row_buf + 1, cp = png_ptr->prev_row + 1; i < row_bytes;
+        i++)
+   {
+      int a, b, c, pa, pb, pc, p;
+
+      b = *pp++;
+      c = *cp++;
+      a = *lp++;
+
+      p = b - c;
+      pc = a - c;
+
+#ifdef PNG_USE_ABS
+      pa = abs(p);
+      pb = abs(pc);
+      pc = abs(p + pc);
+#else
+      pa = p < 0 ? -p : p;
+      pb = pc < 0 ? -pc : pc;
+      pc = (p + pc) < 0 ? -(p + pc) : p + pc;
+#endif
+
+      p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
+
+      *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);
+   }
+}
 #endif /* WRITE_FILTER */
 
 void /* PRIVATE */
@@ -2397,7 +2525,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
 #ifndef PNG_WRITE_FILTER_SUPPORTED
    png_write_filtered_row(png_ptr, png_ptr->row_buf, row_info->rowbytes+1);
 #else
-   png_byte filter_to_do = png_ptr->do_filter;
+   unsigned int filter_to_do = png_ptr->do_filter;
    png_bytep row_buf;
    png_bytep best_row;
    png_uint_32 bpp;
@@ -2443,32 +2571,33 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
     */
    best_row = png_ptr->row_buf;
 
-
-   if ((filter_to_do & PNG_FILTER_NONE) != 0 && filter_to_do != PNG_FILTER_NONE)
+   if (PNG_SIZE_MAX/128 <= row_bytes)
    {
+      /* Overflow can occur in the calculation, just select the lowest set
+       * filter.
+       */
+      filter_to_do &= 0U-filter_to_do;
+   }
+   else if ((filter_to_do & PNG_FILTER_NONE) != 0 &&
+         filter_to_do != PNG_FILTER_NONE)
+   {
+      /* Overflow not possible and multiple filters in the list, including the
+       * 'none' filter.
+       */
       png_bytep rp;
       png_size_t sum = 0;
       png_size_t i;
       int v;
 
-      if (PNG_SIZE_MAX/128 <= row_bytes)
-      {
-         for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
-         {
-            /* Check for overflow */
-            if (sum > PNG_SIZE_MAX/128 - 256)
-               break;
-
-            v = *rp;
-            sum += (v < 128) ? v : 256 - v;
-         }
-      }
-      else /* Overflow is not possible */
       {
          for (i = 0, rp = row_buf + 1; i < row_bytes; i++, rp++)
          {
             v = *rp;
+#ifdef PNG_USE_ABS
+            sum += 128 - abs(v - 128);
+#else
             sum += (v < 128) ? v : 256 - v;
+#endif
          }
       }
 
@@ -2479,7 +2608,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
    if (filter_to_do == PNG_FILTER_SUB)
    /* It's the only filter so no testing is needed */
    {
-      (void) png_setup_sub_row(png_ptr, bpp, row_bytes, mins);
+      png_setup_sub_row_only(png_ptr, bpp, row_bytes);
       best_row = png_ptr->try_row;
    }
 
@@ -2505,7 +2634,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
    /* Up filter */
    if (filter_to_do == PNG_FILTER_UP)
    {
-      (void) png_setup_up_row(png_ptr, row_bytes, mins);
+      png_setup_up_row_only(png_ptr, row_bytes);
       best_row = png_ptr->try_row;
    }
 
@@ -2531,7 +2660,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
    /* Avg filter */
    if (filter_to_do == PNG_FILTER_AVG)
    {
-      (void) png_setup_avg_row(png_ptr, bpp, row_bytes, mins);
+      png_setup_avg_row_only(png_ptr, bpp, row_bytes);
       best_row = png_ptr->try_row;
    }
 
@@ -2555,9 +2684,9 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
    }
 
    /* Paeth filter */
-   if ((filter_to_do == PNG_FILTER_PAETH) != 0)
+   if (filter_to_do == PNG_FILTER_PAETH)
    {
-      (void) png_setup_paeth_row(png_ptr, bpp, row_bytes, mins);
+      png_setup_paeth_row_only(png_ptr, bpp, row_bytes);
       best_row = png_ptr->try_row;
    }
 

projects/vstudio/README.txt

@@ -1,7 +1,7 @@
 
 VisualStudio instructions
 
-libpng version 1.6.22rc01 - May 14, 2016
+libpng version 1.6.24beta05 - July 13, 2016
 
 Copyright (c) 2010,2013,2015 Glenn Randers-Pehrson
 
@@ -93,3 +93,5 @@ as follows:
     DLL               /MD         /MDd
     Static Library    /MD         /MDd
 
+Also, be sure to build libpng, zlib, and your project all for the same
+platform (e.g., 32-bit or 64-bit).

projects/vstudio/libpng/libpng.vcxproj

@@ -84,7 +84,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
@@ -97,9 +97,9 @@
       <BrowseInformation>true</BrowseInformation>
       <CompileAs>CompileAsC</CompileAs>
       <StringPooling>true</StringPooling>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <Optimization>Disabled</Optimization>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
     </ClCompile>
@@ -114,7 +114,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>Use</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -128,9 +128,9 @@
       <BrowseInformation>true</BrowseInformation>
       <CompileAs>CompileAsC</CompileAs>
       <StringPooling>true</StringPooling>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
     </ClCompile>
     <Link>
@@ -140,7 +140,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>Use</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <FunctionLevelLinking>true</FunctionLevelLinking>
@@ -153,9 +153,9 @@
       <CompileAs>CompileAsC</CompileAs>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <Optimization>Full</Optimization>
     </ClCompile>
     <Link>
@@ -170,7 +170,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>Use</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
@@ -184,9 +184,9 @@
       <CompileAs>CompileAsC</CompileAs>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <Optimization>Full</Optimization>
       <WholeProgramOptimization>true</WholeProgramOptimization>
     </ClCompile>

projects/vstudio/pnglibconf/pnglibconf.vcxproj

@@ -30,7 +30,7 @@
   </PropertyGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level3</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <Optimization>MaxSpeed</Optimization>
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>

projects/vstudio/pngstest/pngstest.vcxproj

@@ -76,16 +76,16 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +109,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -117,9 +117,9 @@
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -141,7 +141,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -149,9 +149,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
@@ -176,7 +176,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -185,9 +185,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>

projects/vstudio/pngtest/pngtest.vcxproj

@@ -76,16 +76,16 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +109,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -117,9 +117,9 @@
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -141,7 +141,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -149,9 +149,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
@@ -176,7 +176,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -185,9 +185,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>

projects/vstudio/pngunknown/pngunknown.vcxproj

@@ -76,16 +76,16 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +109,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -117,9 +117,9 @@
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -141,7 +141,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -149,9 +149,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
@@ -176,7 +176,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -185,9 +185,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>

projects/vstudio/pngvalid/pngvalid.vcxproj

@@ -76,16 +76,16 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BasicRuntimeChecks>EnableFastChecks</BasicRuntimeChecks>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -109,7 +109,7 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug Library|Win32'">
     <ClCompile>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <MinimalRebuild>false</MinimalRebuild>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
@@ -117,9 +117,9 @@
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
       <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <StringPooling>true</StringPooling>
       <FunctionLevelLinking>false</FunctionLevelLinking>
@@ -141,7 +141,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -149,9 +149,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;PNG_USE_DLL;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>
@@ -176,7 +176,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>Level4</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <PrecompiledHeader>NotUsing</PrecompiledHeader>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
@@ -185,9 +185,9 @@
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <AdditionalIncludeDirectories>$(ZLibSrcDir);..\..\..\scripts;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <DisableSpecificWarnings>4996;4127</DisableSpecificWarnings>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings)</DisableSpecificWarnings>
       <CompileAsManaged>false</CompileAsManaged>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <StringPooling>true</StringPooling>
       <MinimalRebuild>false</MinimalRebuild>
       <BrowseInformation>true</BrowseInformation>

projects/vstudio/zlib.props

@@ -2,7 +2,7 @@
 <!--
  * zlib.props - location of zlib source
  *
- * libpng version 1.6.22rc01 - May 14, 2016
+ * libpng version 1.6.24beta05 - July 13, 2016
  *
  * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  *
@@ -41,5 +41,18 @@
          test it:
      -->
     <WindowsSDKDesktopARMSupport>true</WindowsSDKDesktopARMSupport>
+
+    <!-- The following lines provide a global (solution level) control of the
+         warnings issued by the compiler, these are used in the individual
+         project files (*/*.vcxproj) with, for zlib, some extra disables.
+
+         Different versions of Visual Studio may require different settings,
+         these settings work with Visual Studio 2013.  Just set
+         TreatWarningAsError to false to check the build without failing on
+         errors.
+     -->
+   <WarningLevel>EnableAllWarnings</WarningLevel>
+   <TreatWarningAsError>true</TreatWarningAsError>
+   <DisableSpecificWarnings>4255;4668;4710;4711;4746;4820;4996</DisableSpecificWarnings>
   </PropertyGroup>
 </Project>

projects/vstudio/zlib/zlib.vcxproj

@@ -88,11 +88,13 @@
     <ClCompile>
       <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
-      <WarningLevel>TurnOffAllWarnings</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
     </ClCompile>
     <Link>
       <TargetMachine>MachineX86</TargetMachine>
@@ -103,11 +105,13 @@
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
     <ClCompile>
       <PreprocessorDefinitions>WIN32;_DEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
-      <WarningLevel>TurnOffAllWarnings</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Disabled</Optimization>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <RuntimeLibrary>MultiThreadedDebugDLL</RuntimeLibrary>
     </ClCompile>
     <Link>
@@ -118,7 +122,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release Library|Win32'">
     <ClCompile>
-      <WarningLevel>Level3</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -126,7 +130,8 @@
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
       <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
@@ -141,7 +146,7 @@
   </ItemDefinitionGroup>
   <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
     <ClCompile>
-      <WarningLevel>Level3</WarningLevel>
+      <WarningLevel>$(WarningLevel)</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
       <Optimization>Full</Optimization>
       <IntrinsicFunctions>true</IntrinsicFunctions>
@@ -149,7 +154,8 @@
       <BufferSecurityCheck>false</BufferSecurityCheck>
       <BrowseInformation>true</BrowseInformation>
       <FunctionLevelLinking>true</FunctionLevelLinking>
-      <TreatWarningAsError>true</TreatWarningAsError>
+      <DisableSpecificWarnings>$(DisableSpecificWarnings);4127;4131;4242;4244</DisableSpecificWarnings>
+      <TreatWarningAsError>$(TreatWarningAsError)</TreatWarningAsError>
       <PreprocessorDefinitions>WIN32;NDEBUG;_WINDOWS;Z_SOLO;%(PreprocessorDefinitions)</PreprocessorDefinitions>
     </ClCompile>
     <Link>

scripts/README.txt

@@ -1,9 +1,9 @@
 
-Makefiles for  libpng version 1.6.22rc01 - May 14, 2016
+Makefiles for  libpng version 1.6.24beta05 - July 13, 2016
 
 pnglibconf.h.prebuilt       =>  Stores configuration settings
  makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng16.so.16.1.6.22rc01)
+                       (gcc, creates libpng16.so.16.1.6.24beta05)
  makefile.gcc      =>  Generic makefile (gcc, creates static libpng.a)
  makefile.knr      =>  Archaic UNIX Makefile that converts files with
                        ansi2knr (Requires ansi2knr.c from
@@ -33,12 +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 libpng16.so.16.1.6.22rc01)
+                       creates libpng16.so.16.1.6.24beta05)
  makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
  makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng16.so.16.1.6.22rc01)
+                       creates libpng16.so.16.1.6.24beta05)
  makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng16.so.16.1.6.22rc01)
+                       creates libpng16.so.16.1.6.24beta05)
  makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
  makefile.sunos    =>  Sun makefile
  makefile.32sunu   =>  Sun Ultra 32-bit makefile

scripts/def.c

@@ -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 1.6.22rc01"
+PNG_DFN ";Version 1.6.24beta05"
 
 #define PNG_EXPORTA(ordinal, type, name, args, attributes)\
         PNG_DFN "@" SYMBOL_PREFIX "@@" name "@"

scripts/libpng-config-head.in

@@ -11,7 +11,7 @@
 
 # Modeled after libxml-config.
 
-version=1.6.22rc01
+version=1.6.24beta05
 prefix=""
 libdir=""
 libs=""

scripts/libpng.pc.in

@@ -5,6 +5,6 @@ includedir=@includedir@/libpng16
 
 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.6.22rc01
+Version: 1.6.24beta05
 Libs: -L${libdir} -lpng16
 Cflags: -I${includedir}

scripts/makefile.cegcc

@@ -23,7 +23,7 @@
 
 VERMAJ = 1
 VERMIN = 6
-VERMIC = 22
+VERMIC = 24
 VER = $(VERMAJ).$(VERMIN).$(VERMIC)
 NAME = libpng
 PACKAGE = $(NAME)-$(VER)

scripts/makefile.linux

@@ -10,7 +10,7 @@
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
-RELEASE = 22
+RELEASE = 24
 
 # Shared library names:
 LIBSO=$(LIBNAME).so

scripts/makefile.msys

@@ -18,7 +18,7 @@ exec_prefix=$(prefix)
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
-RELEASE = 22
+RELEASE = 24
 
 # Shared library names:
 LIBSO=$(LIBNAME).dll

scripts/makefile.ne12bsd

@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include/libpng16
 
 LIB=	png16
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.6.22rc01
+SHLIB_MINOR=	1.6.24beta05
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c

scripts/makefile.netbsd

@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include
 
 LIB=	png
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.22rc01
+SHLIB_MINOR=	1.6.24beta05
 SRCS=	png.c pngset.c pngget.c pngrutil.c pngtrans.c pngwutil.c \
 	pngread.c pngrio.c pngwio.c pngwrite.c pngrtran.c \
 	pngwtran.c pngmem.c pngerror.c pngpread.c

scripts/makefile.openbsd

@@ -11,7 +11,7 @@ LIBDIR=	${PREFIX}/lib
 MANDIR= ${PREFIX}/man/cat
 
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.22rc01
+SHLIB_MINOR=	1.6.24beta05
 
 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \

scripts/pnglibconf.dfa

@@ -552,6 +552,7 @@ option WRITE_ANCILLARY_CHUNKS requires WRITE
 
 # These options disable *all* the text chunks if turned off
 
+option TEXT disabled
 option READ_TEXT requires READ_ANCILLARY_CHUNKS enables TEXT
 option WRITE_TEXT requires WRITE_ANCILLARY_CHUNKS enables TEXT
 

scripts/pnglibconf.h.prebuilt

@@ -1,8 +1,8 @@
-/* libpng 1.6.22rc01 STANDARD API DEFINITION */
+/* libpng 1.6.24beta05 STANDARD API DEFINITION */
 
 /* pnglibconf.h - library build configuration */
 
-/* Libpng version 1.6.22rc01 - May 14, 2016 */
+/* Libpng version 1.6.24beta05 - July 13, 2016 */
 
 /* Copyright (c) 1998-2015 Glenn Randers-Pehrson */
 

scripts/symbols.def

@@ -1,4 +1,4 @@
-;Version 1.6.22rc01
+;Version 1.6.24beta05
 ;--------------------------------------------------------------
 ; LIBPNG symbol list as a Win32 DEF file
 ; Contains all the symbols that can be exported from libpng