[libpng16] Imported from libpng-1.6.17beta03.tar

[libpng16] Eliminated PNG_SAFE_LIMITS macro and restored the 1-million-column
and 1-million-row default limits in pnglibconf.dfa, that can be reset by the user at build time or run time. This provides a more robust defense against DOS and as-yet undiscovered overflows. Display user limits in the output from pngtest.
2025-07-10 18:04:09 +02:00 · 2015-02-17 10:52:21 -06:00 · 2015-02-16 22:52:07 -06:00 · 2015-02-07 09:16:17 -06:00 · 2015-02-07 09:07:09 -06:00 · 2015-02-07 09:03:30 -06:00
73 changed files with 2652 additions and 1635 deletions
--- a/47
+++ b/47
@@ -1,4 +1,4 @@
-Libpng 1.6.15beta01 - October 29, 2014
+Libpng 1.6.17beta03 - February 17, 2015

 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.
@@ -8,27 +8,48 @@ Files available for download:
 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script

-   1.6.15beta01.tar.xz (LZMA-compressed, recommended)
-   1.6.15beta01.tar.gz
+   1.6.17beta03.tar.xz (LZMA-compressed, recommended)
+   1.6.17beta03.tar.gz

 Source files with CRLF line endings (for Windows), without the
 "configure" script

-   lp1615b01.7z  (LZMA-compressed, recommended)
-   lp1615b01.zip
+   lp1617b03.7z  (LZMA-compressed, recommended)
+   lp1617b03.zip

 Other information:

-   1.6.15beta01-README.txt
-   1.6.15beta01-LICENSE.txt
-   libpng-1.6.15beta01-*.asc (armored detached GPG signatures)
+   1.6.17beta03-README.txt
+   1.6.17beta03-LICENSE.txt
+   libpng-1.6.17beta03-*.asc (armored detached GPG signatures)

-Changes since the last public release (1.6.14):
+Changes since the last public release (1.6.16):

-Version 1.6.15beta01 [October 29, 2014]
-  Changed "if (!x)" to "if (x == 0)" and "if (x)" to "if (x !== 0)"
-  Simplified png_free_data().
-  Added missing "ptr = NULL" after some instances of png_free().
+Version 1.6.17beta01 [January 29, 2015]
+  Removed duplicate PNG_SAFE_LIMITS_SUPPORTED handling from pngconf.h
+  Corrected the width limit calculation in png_check_IHDR().
+  Removed user limits from pngfix. Also pass NULL pointers to
+    png_read_row to skip the unnecessary row de-interlace stuff.
+  Added testing of png_set_packing() to pngvalid.c
+  Regenerated configure scripts in the *.tar distributions with libtool-2.4.4
+  Implement previously untested cases of libpng transforms in pngvalid.c
+  Fixed byte order in 2-byte filler, in png_do_read_filler().
+  Made the check for out-of-range values in png_set_tRNS() detect
+    values that are exactly 2^bit_depth, and work on 16-bit platforms.
+  Merged some parts of libpng-1.6.17beta01 and libpng-1.7.0beta47.
+  Added #ifndef __COVERITY__ where needed in png.c, pngrutil.c and
+    pngset.c to avoid warnings about dead code.
+
+Version 1.6.17beta02 [February 7, 2015]
+  Work around one more Coverity-scan dead-code warning.
+  Do not build png_product2() when it is unused.
+
+Version 1.6.17beta03 [February 17, 2015]
+  Display user limits in the output from pngtest.
+  Eliminated the PNG_SAFE_LIMITS macro and restored the 1-million-column
+    and 1-million-row default limits in pnglibconf.dfa, that can be reset
+    by the user at build time or run time.  This provides a more robust
+    defense against DOS and as-yet undiscovered overflows.

 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
--- a/116
+++ b/116
@@ -5034,10 +5034,124 @@ Version 1.6.14 [October 23, 2014]
  No changes.

 Version 1.6.15beta01 [October 29, 2014]
-  Changed "if (!x)" to "if (x == 0)" and "if (x)" to "if (x !== 0)"
+  Changed "if (!x)" to "if (x == 0)" and "if (x)" to "if (x != 0)"
  Simplified png_free_data().
  Added missing "ptr = NULL" after some instances of png_free().

+Version 1.6.15beta02 [November 1, 2014]
+  Changed remaining "if (!x)" to "if (x == 0)" and "if (x)" to "if (x != 0)"
+
+Version 1.6.15beta03 [November 3, 2014]
+  Added PNG_USE_ARM_NEON configuration flag (Marcin Juszkiewicz).
+
+Version 1.6.15beta04 [November 4, 2014]
+  Removed new PNG_USE_ARM_NEON configuration flag and made a one-line
+    revision to configure.ac to support ARM on aarch64 instead (John Bowler).
+
+Version 1.6.15beta05 [November 5, 2014]
+  Use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING in
+    example.c, pngtest.c, and applications in the contrib directory.
+  Avoid out-of-bounds memory access in png_user_version_check().
+  Simplified and future-proofed png_user_version_check().
+  Fixed GCC unsigned int->float warnings. Various versions of GCC
+    seem to generate warnings when an unsigned value is implicitly
+    converted to double. This is probably a GCC bug but this change
+    avoids the issue by explicitly converting to (int) where safe.
+  Free all allocated memory in pngimage. The file buffer cache was left
+    allocated at the end of the program, harmless but it causes memory
+    leak reports from clang.
+  Fixed array size calculations to avoid warnings. At various points
+    in the code the number of elements in an array is calculated using
+    sizeof.  This generates a compile time constant of type (size_t) which
+    is then typically assigned to an (unsigned int) or (int). Some versions
+    of GCC on 64-bit systems warn about the apparent narrowing, even though
+    the same compiler does apparently generate the correct, in-range,
+    numeric constant.  This adds appropriate, safe, casts to make the
+    warnings go away.
+
+Version 1.6.15beta06 [November 6, 2014]
+  Reverted use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING
+    in the manual, example.c, pngtest.c, and applications in the contrib
+    directory.  It was incorrect advice.
+
+Version 1.6.15beta07 [November 7, 2014]
+  Removed #ifdef PNG_16BIT_SUPPORTED/#endif around png_product2(); it is
+    needed by png_reciprocal2().
+  Added #ifdef PNG_16BIT_SUPPORTED/#endif around png_log16bit() and
+    png_do_swap().
+  Changed all "#endif /* PNG_FEATURE_SUPPORTED */" to "#endif /* FEATURE */"
+
+Version 1.6.15beta08 [November 8, 2014]
+  More housecleaning in *.h
+
+Version 1.6.15rc01 [November 13, 2014]
+
+Version 1.6.15rc02 [November 14, 2014]
+  The macros passed in the command line to Borland make were ignored if
+    similarly-named macros were already defined in makefiles. This behavior
+    is different from POSIX make and other make programs.  Surround the
+    macro definitions with ifndef guards (Cosmin).
+
+Version 1.6.15rc03 [November 16, 2014]
+  Added "-D_CRT_SECURE_NO_WARNINGS" to CFLAGS in scripts/makefile.vcwin32.
+  Removed the obsolete $ARCH variable from scripts/makefile.darwin.
+
+Version 1.6.15 [November 20, 2014]
+  No changes.
+
+Version 1.6.16beta01 [December 14, 2014]
+  Added ".align 2" to arm/filter_neon.S to support old GAS assemblers that
+    don't do alignment correctly.
+  Revised Makefile.am and scripts/symbols.dfn to work with MinGW/MSYS
+    (Bob Friesenhahn).
+
+Version 1.6.16beta02 [December 15, 2014]
+  Revised Makefile.am and scripts/*.dfn again to work with MinGW/MSYS;
+    renamed scripts/*.dfn to scripts/*.c (John Bowler).
+
+Version 1.6.16beta03 [December 21, 2014]
+  Quiet a "comparison always true" warning in pngstest.c (John Bowler).
+
+Version 1.6.16rc01 [December 21, 2014]
+  Restored a test on width that was removed from png.c at libpng-1.6.9
+    (Bug report by Alex Eubanks, CVE-2015-0973).
+
+Version 1.6.16rc02 [December 21, 2014]
+  Undid the update to pngrutil.c in 1.6.16rc01.
+
+Version 1.6.16rc03 [December 21, 2014]
+  Fixed an overflow in png_combine_row() with very wide interlaced images
+    (Bug report and fix by John Bowler, CVE-2014-9495).
+
+Version 1.6.16 [December 22, 2014]
+  No changes.
+
+Version 1.6.17beta01 [January 29, 2015]
+  Removed duplicate PNG_SAFE_LIMITS_SUPPORTED handling from pngconf.h
+  Corrected the width limit calculation in png_check_IHDR().
+  Removed user limits from pngfix. Also pass NULL pointers to
+    png_read_row to skip the unnecessary row de-interlace stuff.
+  Added testing of png_set_packing() to pngvalid.c
+  Regenerated configure scripts in the *.tar distributions with libtool-2.4.4
+  Implement previously untested cases of libpng transforms in pngvalid.c
+  Fixed byte order in 2-byte filler, in png_do_read_filler().
+  Made the check for out-of-range values in png_set_tRNS() detect
+    values that are exactly 2^bit_depth, and work on 16-bit platforms.
+  Merged some parts of libpng-1.6.17beta01 and libpng-1.7.0beta47.
+  Added #ifndef __COVERITY__ where needed in png.c, pngrutil.c and
+    pngset.c to avoid warnings about dead code.
+
+Version 1.6.17beta02 [February 7, 2015]
+  Work around one more Coverity-scan dead-code warning.
+  Do not build png_product2() when it is unused.
+
+Version 1.6.17beta03 [February 17, 2015]
+  Display user limits in the output from pngtest.
+  Eliminated the PNG_SAFE_LIMITS macro and restored the 1-million-column
+    and 1-million-row default limits in pnglibconf.dfa, that can be reset
+    by the user at build time or run time.  This provides a more robust
+    defense against DOS and as-yet undiscovered overflows.
+
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -16,7 +16,7 @@ enable_testing()

 set(PNGLIB_MAJOR 1)
 set(PNGLIB_MINOR 6)
-set(PNGLIB_RELEASE 15)
+set(PNGLIB_RELEASE 17)
 set(PNGLIB_NAME libpng${PNGLIB_MAJOR}${PNGLIB_MINOR})
 set(PNGLIB_VERSION ${PNGLIB_MAJOR}.${PNGLIB_MINOR}.${PNGLIB_RELEASE})

@@ -253,7 +253,7 @@ endif(NOT WIN32 OR CYGWIN OR MINGW)
 # SET UP LINKS
 if(PNG_SHARED)
  set_target_properties(${PNG_LIB_NAME} PROPERTIES
-#   VERSION 16.${PNGLIB_RELEASE}.1.6.15beta01
+#   VERSION 16.${PNGLIB_RELEASE}.1.6.17beta03
    VERSION 16.${PNGLIB_RELEASE}.0
    SOVERSION 16
    CLEAN_DIRECT_OUTPUT 1)
--- a/6
+++ b/6
@@ -10,8 +10,8 @@ this sentence.

 This code is released under the libpng license.

-libpng versions 1.2.6, August 15, 2004, through 1.6.15beta01, October 29, 2014, are
-Copyright (c) 2004, 2006-2014 Glenn Randers-Pehrson, and are
+libpng versions 1.2.6, August 15, 2004, through 1.6.17beta03, February 17, 2015, are
+Copyright (c) 2004, 2006-2015 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors

@@ -108,4 +108,4 @@ certification mark of the Open Source Initiative.

 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-October 29, 2014
+February 17, 2015
--- a/Makefile.am
+++ b/Makefile.am
@@ -129,7 +129,7 @@ EXTRA_DIST= \
 	$(TESTS) $(XFAIL_TESTS) tests/pngstest \
 	CMakeLists.txt example.c libpng-manual.txt

-SCRIPT_CLEANFILES=scripts/*.out scripts/*.chk scripts/pnglibconf.dfn
+SCRIPT_CLEANFILES=scripts/*.out scripts/*.chk scripts/pnglibconf.c

 CLEANFILES= *.tf? pngout.png libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@.pc \
 	libpng@PNGLIB_MAJOR@@PNGLIB_MINOR@-config libpng.vers libpng.sym \
@@ -152,7 +152,7 @@ AM_CFLAGS = ${PNG_COPTS}
 # checks for this and sets DFNCPP appropriately.
 DFNCPP = @DFNCPP@

-SUFFIXES = .chk .dfn .out
+SUFFIXES = .chk .out

 $(PNGLIB_BASENAME).pc: libpng.pc
 	cp libpng.pc $@
@@ -237,18 +237,17 @@ if DO_PNG_PREFIX
 SYMBOL_CFLAGS += -DPNG_PREFIX='@PNG_PREFIX@'
 endif

-.dfn.out:
-	rm -f $@ $*.c $*.tf[12]
+.c.out:
+	rm -f $@ $*.tf[12]
 	test -d scripts || mkdir scripts || test -d scripts
-	echo '#include "$<"' >$*.c
 	$(DFNCPP) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES)\
-	    $(CPPFLAGS) $(SYMBOL_CFLAGS) $*.c > $*.tf1
+	    $(CPPFLAGS) $(SYMBOL_CFLAGS) $< > $*.tf1
 	$(AWK) -f "${srcdir}/scripts/dfn.awk" out="$*.tf2" $*.tf1 1>&2
-	rm -f $*.c $*.tf1
+	rm -f $*.tf1
 	mv $*.tf2 $@

-# The .dfn file for pnglibconf.h is machine generated
-pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)
+# The .c file for pnglibconf.h is machine generated
+pnglibconf.c: scripts/pnglibconf.dfa scripts/options.awk pngconf.h pngusr.dfa $(DFA_XTRA)
 	rm -f $@ $*.tf[45]
 	$(AWK) -f ${srcdir}/scripts/options.awk out=$*.tf4 version=search\
 	    ${srcdir}/pngconf.h ${srcdir}/scripts/pnglibconf.dfa\
@@ -268,7 +267,7 @@ scripts/symbols.chk: scripts/checksym.awk scripts/symbols.def scripts/symbols.ou

 # used on demand to regenerate the standard header, CPPFLAGS should
 # be empty - no non-standard defines
-scripts/pnglibconf.dfn: scripts/pnglibconf.dfa scripts/options.awk pngconf.h
+scripts/pnglibconf.c: scripts/pnglibconf.dfa scripts/options.awk pngconf.h
 	rm -f $@ pnglibconf.tf[67]
 	test -z "$(CPPFLAGS)"
 	echo "com @PNGLIB_VERSION@ STANDARD API DEFINITION" |\
--- a/2
+++ b/2
@@ -1,4 +1,4 @@
-README for libpng version 1.6.15beta01 - October 29, 2014 (shared library 16.0)
+README for libpng version 1.6.17beta03 - February 17, 2015 (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.
--- a/arm/arm_init.c
+++ b/arm/arm_init.c
@@ -3,7 +3,7 @@
 *
 * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.10 [March 6, 2014]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -17,6 +17,7 @@
 #include "../pngpriv.h"

 #ifdef PNG_READ_SUPPORTED
+
 #if PNG_ARM_NEON_OPT > 0
 #ifdef PNG_ARM_NEON_CHECK_SUPPORTED /* Do run-time checks */
 /* WARNING: it is strongly recommended that you do not build libpng with
@@ -130,4 +131,4 @@ png_init_filter_functions_neon(png_structp pp, unsigned int bpp)
   }
 }
 #endif /* PNG_ARM_NEON_OPT > 0 */
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ */
--- a/arm/filter_neon.S
+++ b/arm/filter_neon.S
@@ -1,18 +1,17 @@

 /* filter_neon.S - NEON optimised filter functions
 *
- * Copyright (c) 2013 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by Mans Rullgard, 2011.
- * Last changed in libpng 1.6.8 [December 19, 2013]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
 */

-/* This is required to get the symbol renames, which are #defines, and also
- * includes the definition (or not) of PNG_ARM_NEON_OPT and
- * PNG_ARM_NEON_IMPLEMENTATION.
+/* This is required to get the symbol renames, which are #defines, and the
+ * definitions (or not) of PNG_ARM_NEON_OPT and PNG_ARM_NEON_IMPLEMENTATION.
 */
 #define PNG_VERSION_INFO_ONLY
 #include "../pngpriv.h"
@@ -21,6 +20,8 @@
 .section .note.GNU-stack,"",%progbits /* mark stack as non-executable */
 #endif

+#ifdef PNG_READ_SUPPORTED
+
 /* Assembler NEON support - only works for 32-bit ARM (i.e. it does not work for
 * ARM64).  The code in arm/filter_neon_intrinsics.c supports ARM64, however it
 * only works if -mfpu=neon is specified on the GCC command line.  See pngpriv.h
@@ -28,7 +29,6 @@
 */
 #if PNG_ARM_NEON_IMPLEMENTATION == 2 /* hand-coded assembler */

-#ifdef PNG_READ_SUPPORTED
 #if PNG_ARM_NEON_OPT > 0

 #ifdef __ELF__
@@ -47,6 +47,13 @@ ELF     .size   \name, . - \name
        .purgem endfunc
    .endm
        .text
+
+        /* Explicitly specifying alignment here because some versions of
+         * GAS don't align code correctly.  This is harmless in correctly
+         * written versions of GAS.
+         */
+        .align 2
+
    .if \export
        .global \name
    .endif
@@ -242,5 +249,5 @@ func    png_read_filter_row_paeth3_neon, export=1
        pop             {r4,pc}
 endfunc
 #endif /* PNG_ARM_NEON_OPT > 0 */
-#endif /* PNG_READ_SUPPORTED */
 #endif /* PNG_ARM_NEON_IMPLEMENTATION == 2 (assembler) */
+#endif /* READ */
--- a/arm/filter_neon_intrinsics.c
+++ b/arm/filter_neon_intrinsics.c
@@ -1,11 +1,11 @@

 /* filter_neon_intrinsics.c - NEON optimised filter functions
 *
- * Copyright (c) 2013 Glenn Randers-Pehrson
+ * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by James Yu <james.yu at linaro.org>, October 2013.
 * Based on filter_neon.S, written by Mans Rullgard, 2011.
 *
- * Last changed in libpng 1.6.8 [December 19, 2013]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -14,6 +14,8 @@

 #include "../pngpriv.h"

+#ifdef PNG_READ_SUPPORTED
+
 /* This code requires -mfpu=neon on the command line: */
 #if PNG_ARM_NEON_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */

@@ -35,7 +37,6 @@
 #define png_ldr(type,pointer)\
   (temp_pointer = png_ptr(type,pointer), *temp_pointer)

-#ifdef PNG_READ_SUPPORTED
 #if PNG_ARM_NEON_OPT > 0

 void
@@ -368,5 +369,5 @@ png_read_filter_row_paeth4_neon(png_row_infop row_info, png_bytep row,
 }

 #endif /* PNG_ARM_NEON_OPT > 0 */
-#endif /* PNG_READ_SUPPORTED */
 #endif /* PNG_ARM_NEON_IMPLEMENTATION == 1 (intrinsics) */
+#endif /* READ */
--- a/configure.ac
+++ b/configure.ac
@@ -18,7 +18,7 @@ AC_PREREQ([2.68])

 dnl Version number stuff here:

-AC_INIT([libpng],[1.6.15beta01],[png-mng-implement@lists.sourceforge.net])
+AC_INIT([libpng],[1.6.17beta03],[png-mng-implement@lists.sourceforge.net])
 AC_CONFIG_MACRO_DIR([scripts])

 # libpng does not follow GNU file name conventions (hence 'foreign')
@@ -39,10 +39,10 @@ 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=1.6.15beta01
+PNGLIB_VERSION=1.6.17beta03
 PNGLIB_MAJOR=1
 PNGLIB_MINOR=6
-PNGLIB_RELEASE=15
+PNGLIB_RELEASE=17

 dnl End of version number stuff

@@ -310,7 +310,7 @@ AC_ARG_ENABLE([arm-neon],
 AM_CONDITIONAL([PNG_ARM_NEON],
   [test "$enable_arm_neon" != 'no' &&
    case "$host_cpu" in
-      arm*) :;;
+      arm*|aarch64*) :;;
      *)    test "$enable_arm_neon" != '';;
    esac])

--- a/contrib/arm-neon/linux.c
+++ b/contrib/arm-neon/linux.c
@@ -2,7 +2,7 @@
 *
 * Copyright (c) 2014 Glenn Randers-Pehrson
 * Written by John Bowler, 2014.
- * Last changed in libpng 1.6.10 [March 6, 2014]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -16,8 +16,8 @@
 * png_have_neon implemented for Linux by reading the widely available
 * pseudo-file /proc/cpuinfo.
 *
- * This code is strict ANSI-C and is probably moderately portable, it does
- * however use <stdio.h> and assumes that /proc/cpuinfo is never localized.
+ * This code is strict ANSI-C and is probably moderately portable; it does
+ * however use <stdio.h> and it assumes that /proc/cpuinfo is never localized.
 */
 #include <stdio.h>

@@ -152,8 +152,10 @@ png_have_neon(png_structp png_ptr)
      }
   }

+#ifdef PNG_WARNINGS_SUPPORTED
   else
      png_warning(png_ptr, "/proc/cpuinfo open failed");
+#endif

   return 0;
 }
--- a/contrib/gregbook/readpng.c
+++ b/contrib/gregbook/readpng.c
@@ -100,7 +100,8 @@ int readpng_init(FILE *infile, ulg *pWidth, ulg *pHeight)

    /* could pass pointers to user-defined error handlers instead of NULLs: */

-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    png_ptr = png_create_read_struct(png_get_libpng_ver(NULL), NULL, NULL,
+        NULL);
    if (!png_ptr)
        return 4;   /* out of memory */

--- a/contrib/gregbook/readpng2.c
+++ b/contrib/gregbook/readpng2.c
@@ -104,7 +104,7 @@ int readpng2_init(mainprog_info *mainprog_ptr)

    /* could also replace libpng warning-handler (final NULL), but no need: */

-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+    png_ptr = png_create_read_struct(png_get_libpng_ver(NULL), mainprog_ptr,
      readpng2_error_handler, readpng2_warning_handler);
    if (!png_ptr)
        return 4;   /* out of memory */
--- a/contrib/gregbook/writepng.c
+++ b/contrib/gregbook/writepng.c
@@ -90,7 +90,7 @@ int writepng_init(mainprog_info *mainprog_ptr)

    /* could also replace libpng warning-handler (final NULL), but no need: */

-    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+    png_ptr = png_create_write_struct(png_get_libpng_ver(NULL), mainprog_ptr,
      writepng_error_handler, NULL);
    if (!png_ptr)
        return 4;   /* out of memory */
--- a/contrib/libtests/pngimage.c
+++ b/contrib/libtests/pngimage.c
@@ -337,6 +337,9 @@ validate_T(void)
 *    In both cases the file data is held in a linked list of buffers - not all
 *    of these are in use at any time.
 */
+#define NEW(type) ((type *)malloc(sizeof (type)))
+#define DELETE(ptr) (free(ptr))
+
 struct buffer_list
 {
   struct buffer_list *next;         /* next buffer in list */
@@ -361,6 +364,25 @@ buffer_init(struct buffer *buffer)
   buffer->current = NULL;
 }

+static void
+buffer_destroy_list(struct buffer_list *list)
+{
+   if (list != NULL)
+   {
+      struct buffer_list *next = list->next;
+      DELETE(list);
+      buffer_destroy_list(next);
+   }
+}
+
+static void
+buffer_destroy(struct buffer *buffer)
+{
+   struct buffer_list *list = buffer->first.next;
+   buffer_init(buffer);
+   buffer_destroy_list(list);
+}
+
 #ifdef PNG_WRITE_SUPPORTED
 static void
 buffer_start_write(struct buffer *buffer)
@@ -390,8 +412,6 @@ get_buffer(png_structp pp)
   return (struct buffer*)png_get_io_ptr(pp);
 }

-#define NEW(type) ((type *)malloc(sizeof (type)))
-
 static struct buffer_list *
 buffer_extend(struct buffer_list *current)
 {
@@ -598,6 +618,17 @@ display_clean(struct display *dp)
   dp->results = 0; /* reset for next time */
 }

+static void
+display_destroy(struct display *dp)
+{
+    /* Release any memory held in the display. */
+#  ifdef PNG_WRITE_SUPPORTED
+      buffer_destroy(&dp->written_file);
+#  endif
+
+   buffer_destroy(&dp->original_file);
+}
+
 static struct display *
 get_dp(png_structp pp)
   /* The display pointer is always stored in the png_struct error pointer */
@@ -1605,6 +1636,9 @@ main(const int argc, const char * const * const argv)
         display_clean(&d);
      }

+      /* Release allocated memory */
+      display_destroy(&d);
+
      return errors != 0;
   }
 }
--- a/contrib/libtests/pngstest.c
+++ b/contrib/libtests/pngstest.c
@@ -1,9 +1,9 @@
 /*-
 * pngstest.c
 *
- * Copyright (c) 2013 John Cunningham Bowler
+ * Copyright (c) 2013-2014 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.8 [December 19, 2013]
+ * Last changed in libpng 1.6.16 [December 22, 2014]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -3173,32 +3173,43 @@ read_one_file(Image *image)
            {
               long int cb = ftell(f);

-               if (cb > 0 && (unsigned long int)cb < (size_t)~(size_t)0)
+               if (cb > 0)
               {
-                  png_bytep b = voidcast(png_bytep, malloc((size_t)cb));
-
-                  if (b != NULL)
+                  if ((unsigned long int)cb <= (size_t)~(size_t)0)
                  {
-                     rewind(f);
+                     png_bytep b = voidcast(png_bytep, malloc((size_t)cb));

-                     if (fread(b, (size_t)cb, 1, f) == 1)
+                     if (b != NULL)
                     {
-                        fclose(f);
-                        image->input_memory_size = cb;
-                        image->input_memory = b;
+                        rewind(f);
+
+                        if (fread(b, (size_t)cb, 1, f) == 1)
+                        {
+                           fclose(f);
+                           image->input_memory_size = cb;
+                           image->input_memory = b;
+                        }
+
+                        else
+                        {
+                           free(b);
+                           return logclose(image, f, image->file_name,
+                              ": read failed: ");
+                        }
                     }

                     else
-                     {
-                        free(b);
                        return logclose(image, f, image->file_name,
-                           ": read failed: ");
-                     }
+                           ": out of memory: ");
                  }

                  else
                     return logclose(image, f, image->file_name,
-                        ": out of memory: ");
+                        ": file too big for this architecture: ");
+                     /* cb is the length of the file as a (long) and
+                      * this is greater than the maximum amount of
+                      * memory that can be requested from malloc.
+                      */
               }

               else if (cb == 0)
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
--- a/contrib/pngminus/png2pnm.c
+++ b/contrib/pngminus/png2pnm.c
@@ -223,7 +223,7 @@ BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file,

  /* create png and info structures */

-  png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING,
+  png_ptr = png_create_read_struct (png_get_libpng_ver(NULL),
    NULL, NULL, NULL);
  if (!png_ptr)
    return FALSE;   /* out of memory */
--- a/contrib/pngminus/pnm2png.c
+++ b/contrib/pngminus/pnm2png.c
@@ -425,7 +425,8 @@ BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace,
  } /* end for row */

  /* prepare the standard PNG structures */
-  png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+  png_ptr = png_create_write_struct (png_get_libpng_ver(NULL), NULL, NULL,
+      NULL);
  if (!png_ptr)
  {
    return FALSE;
--- a/contrib/tools/pngfix.c
+++ b/contrib/tools/pngfix.c
@@ -1,15 +1,15 @@
 /* pngfix.c
 *
- * Copyright (c) 2014 John Cunningham Bowler
+ * Copyright (c) 2014-2015 John Cunningham Bowler
 *
- * Last changed in libpng 1.6.14 [October 23, 2014]
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
 * and license in png.h
 *
- * Tool to check and fix the zlib inflate 'too far back' problem, see the usage
- * message for more information.
+ * Tool to check and fix the zlib inflate 'too far back' problem.
+ * See the usage message for more information.
 */
 #include <stdlib.h>
 #include <stdio.h>
@@ -3577,7 +3577,6 @@ read_png(struct control *control)
 {
   png_structp png_ptr;
   png_infop info_ptr = NULL;
-   volatile png_bytep row = NULL, display = NULL;
   volatile int rc;

   png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, control,
@@ -3594,6 +3593,16 @@ read_png(struct control *control)
   rc = setjmp(control->file.jmpbuf);
   if (rc == 0)
   {
+#     ifdef PNG_SET_USER_LIMITS_SUPPORTED
+         /* Remove any limits on the size of PNG files that can be read,
+          * without this we may reject files based on built-in safety
+          * limits.
+          */
+         png_set_user_limits(png_ptr, 0x7fffffff, 0x7fffffff);
+         png_set_chunk_cache_max(png_ptr, 0);
+         png_set_chunk_malloc_max(png_ptr, 0);
+#     endif
+
      png_set_read_fn(png_ptr, control, read_callback);

      info_ptr = png_create_info_struct(png_ptr);
@@ -3606,32 +3615,22 @@ read_png(struct control *control)
      png_read_info(png_ptr, info_ptr);

      {
-         png_size_t rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+        png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
+        int passes = png_set_interlace_handling(png_ptr);
+        int pass;

-         row = png_voidcast(png_byte*, malloc(rowbytes));
-         display = png_voidcast(png_byte*, malloc(rowbytes));
+        png_start_read_image(png_ptr);

-         if (row == NULL || display == NULL)
-            png_error(png_ptr, "OOM allocating row buffers");
+        for (pass = 0; pass < passes; ++pass)
+        {
+           png_uint_32 y = height;

-         {
-            png_uint_32 height = png_get_image_height(png_ptr, info_ptr);
-            int passes = png_set_interlace_handling(png_ptr);
-            int pass;
-
-            png_start_read_image(png_ptr);
-
-            for (pass = 0; pass < passes; ++pass)
-            {
-               png_uint_32 y = height;
-
-               /* NOTE: this trashes the row each time; interlace handling won't
-                * work, but this avoids memory thrashing for speed testing.
-                */
-               while (y-- > 0)
-                  png_read_row(png_ptr, row, display);
-            }
-         }
+           /* NOTE: this skips asking libpng to return either version of
+            * the image row, but libpng still reads the rows.
+            */
+           while (y-- > 0)
+              png_read_row(png_ptr, NULL, NULL);
+        }
      }

      if (control->file.global->verbose)
@@ -3642,8 +3641,6 @@ read_png(struct control *control)
   }

   png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
-   if (row != NULL) free(row);
-   if (display != NULL) free(display);
   return rc;
 }

--- a/contrib/visupng/PngFile.c
+++ b/contrib/visupng/PngFile.c
@@ -136,7 +136,7 @@ BOOL PngLoadImage (PTSTR pstrFileName, png_byte **ppbImageData,

    /* create the two png(-info) structures */

-    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,
+    png_ptr = png_create_read_struct(png_get_libpng_ver(NULL), NULL,
      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
    if (!png_ptr)
    {
@@ -313,7 +313,7 @@ BOOL PngSaveImage (PTSTR pstrFileName, png_byte *pDiData,

    /* prepare the standard PNG structures */

-    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL,
+    png_ptr = png_create_write_struct(png_get_libpng_ver(NULL), NULL,
      (png_error_ptr)png_cexcept_error, (png_error_ptr)NULL);
    if (!png_ptr)
    {
--- a/example.c
+++ b/example.c
@@ -2,7 +2,7 @@
 #if 0 /* in case someone actually tries to compile this */

 /* example.c - an example of using libpng
- * Last changed in libpng 1.6.11 [June 5, 2014]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Maintained 1998-2014 Glenn Randers-Pehrson
 * Maintained 1996, 1997 Andreas Dilger)
 * Written 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -52,7 +52,7 @@ int main(int argc, const char **argv)
      image.version = PNG_IMAGE_VERSION;

      /* The first argument is the file to read: */
-      if (png_image_begin_read_from_file(&image, argv[1]))
+      if (png_image_begin_read_from_file(&image, argv[1]) != 0)
      {
         png_bytep buffer;

@@ -97,7 +97,7 @@ int main(int argc, const char **argv)
          */
         if (buffer != NULL &&
            png_image_finish_read(&image, NULL/*background*/, buffer,
-               0/*row_stride*/, NULL/*colormap*/))
+               0/*row_stride*/, NULL/*colormap*/) != 0)
         {
            /* Now write the image out to the second argument.  In the write
             * call 'convert_to_8bit' allows 16-bit data to be squashed down to
@@ -105,7 +105,7 @@ int main(int argc, const char **argv)
             * to the 8-bit format.
             */
            if (png_image_write_to_file(&image, argv[2], 0/*convert_to_8bit*/,
-               buffer, 0/*row_stride*/, NULL/*colormap*/))
+               buffer, 0/*row_stride*/, NULL/*colormap*/) != 0)
            {
               /* The image has been written successfully. */
               exit(0);
@@ -405,7 +405,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
   /* Expand paletted or RGB images with transparency to full alpha channels
    * so the data will be available as RGBA quartets.
    */
-   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS) != 0)
      png_set_tRNS_to_alpha(png_ptr);

   /* Set the background color to draw transparent and alpha images over.
@@ -417,7 +417,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */

   png_color_16 my_background, *image_background;

-   if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+   if (png_get_bKGD(png_ptr, info_ptr, &image_background) != 0)
      png_set_background(png_ptr, image_background,
                         PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
   else
@@ -454,12 +454,12 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */

   int intent;

-   if (png_get_sRGB(png_ptr, info_ptr, &intent))
+   if (png_get_sRGB(png_ptr, info_ptr, &intent) != 0)
      png_set_gamma(png_ptr, screen_gamma, PNG_DEFAULT_sRGB);
   else
   {
      double image_gamma;
-      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
+      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma) != 0)
         png_set_gamma(png_ptr, screen_gamma, image_gamma);
      else
         png_set_gamma(png_ptr, screen_gamma, 0.45455);
@@ -469,7 +469,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
   /* Quantize RGB files down to 8 bit palette or reduce palettes
    * to the number of colors available on your screen.
    */
-   if (color_type & PNG_COLOR_MASK_COLOR)
+   if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
   {
      int num_palette;
      png_colorp palette;
@@ -484,7 +484,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
            MAX_SCREEN_COLORS, NULL, 0);
      }
      /* This reduces the image to the palette supplied in the file */
-      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette))
+      else if (png_get_PLTE(png_ptr, info_ptr, &palette, &num_palette) != 0)
      {
         png_uint_16p histogram = NULL;

@@ -494,7 +494,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
                        max_screen_colors, histogram, 0);
      }
   }
-#endif /* PNG_READ_QUANTIZE_SUPPORTED */
+#endif /* READ_QUANTIZE */

   /* Invert monochrome files to have 0 as white and 1 as black */
   png_set_invert_mono(png_ptr);
@@ -503,7 +503,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
    * [0,65535] to the original [0,7] or [0,31], or whatever range the
    * colors were originally in:
    */
-   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT))
+   if (png_get_valid(png_ptr, info_ptr, PNG_INFO_sBIT) != 0)
   {
      png_color_8p sig_bit_p;

@@ -512,7 +512,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
   }

   /* Flip the RGB pixels to BGR (or RGBA to BGRA) */
-   if (color_type & PNG_COLOR_MASK_COLOR)
+   if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
      png_set_bgr(png_ptr);

   /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
@@ -532,7 +532,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* File is already open */
   number_passes = png_set_interlace_handling(png_ptr);
 #else
   number_passes = 1;
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */


   /* Optional call to gamma correct and add the background to the palette
@@ -744,7 +744,7 @@ row_callback(png_structp png_ptr, png_bytep new_row,
    * to pass the current row as new_row, and the function will combine
    * the old row and the new row.
    */
-#endif /* PNG_READ_INTERLACING_SUPPORTED */
+#endif /* READ_INTERLACING */
 }

 end_callback(png_structp png_ptr, png_infop info)
--- a/libpng-manual.txt
+++ b/libpng-manual.txt
@@ -1,9 +1,9 @@
 libpng-manual.txt - A description on how to use and modify libpng

- libpng version 1.6.15beta01 - October 29, 2014
+ libpng version 1.6.17beta03 - February 17, 2015
 Updated and distributed by Glenn Randers-Pehrson
 <glennrp at users.sourceforge.net>
- Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ Copyright (c) 1998-2015 Glenn Randers-Pehrson

 This document is released under the libpng license.
 For conditions of distribution and use, see the disclaimer
@@ -11,9 +11,9 @@ libpng-manual.txt - A description on how to use and modify libpng

 Based on:

- libpng versions 0.97, January 1998, through 1.6.15beta01 - October 29, 2014
+ libpng versions 0.97, January 1998, through 1.6.17beta03 - February 17, 2015
 Updated and distributed by Glenn Randers-Pehrson
- Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ Copyright (c) 1998-2015 Glenn Randers-Pehrson

 libpng 1.0 beta 6 - version 0.96 - May 28, 1997
 Updated and distributed by Andreas Dilger
@@ -344,22 +344,23 @@ then only check the bytes (if any) that your program didn't read.
 to replace them with custom functions.  See the discussion under
 Customizing libpng.

-
    FILE *fp = fopen(file_name, "rb");
    if (!fp)
    {
       return (ERROR);
    }

-    fread(header, 1, number, fp);
-    is_png = !png_sig_cmp(header, 0, number);
+    if (fread(header, 1, number, fp) != number)
+    {
+       return (ERROR);
+    }

+    is_png = !png_sig_cmp(header, 0, number);
    if (!is_png)
    {
       return (NOT_PNG);
    }

-
 Next, png_struct and png_info need to be allocated and initialized.  In
 order to ensure that the size of these structures is correct even with a
 dynamically linked libpng, there are functions to initialize and
@@ -648,15 +649,12 @@ User limits

 The PNG specification allows the width and height of an image to be as
 large as 2^31-1 (0x7fffffff), or about 2.147 billion rows and columns.
-Since very few applications really need to process such large images,
-we have imposed an arbitrary 1-million limit on rows and columns.
 Larger images will be rejected immediately with a png_error() call. If
-you wish to change this limit, you can use
+you wish to reduce these limits, you can use

   png_set_user_limits(png_ptr, width_max, height_max);

-to set your own limits, or use width_max = height_max = 0x7fffffffL
-to allow all valid dimensions (libpng may reject some very large images
+to set your own limits (libpng may reject some very wide images
 anyway because of potential buffer overflow conditions).

 You should put this statement after you create the PNG structure and
@@ -5037,8 +5035,8 @@ where "rp" indicates a "restricted pointer".
 Error detection in some chunks has improved; in particular the iCCP chunk
 reader now does pretty complete validation of the basic format.  Some bad
 profiles that were previously accepted are now accepted with a warning or
-rejected, depending upon the png_set_benign_errors() setting, in particular the
-very old broken Microsoft/HP 3144-byte sRGB profile.  Starting with
+rejected, depending upon the png_set_benign_errors() setting, in particular
+the very old broken Microsoft/HP 3144-byte sRGB profile.  Starting with
 libpng-1.6.11, recognizing and checking sRGB profiles can be avoided by
 means of

@@ -5048,8 +5046,8 @@ means of
           PNG_OPTION_ON);
    #endif

-It's not a good idea to do this if you are using the "simplified API",
-which needs to be able to recognize an sRGB profile conveyed via the iCCP
+It's not a good idea to do this if you are using the new "simplified API",
+which needs to be able to recognize sRGB profiles conveyed via the iCCP
 chunk.

 The PNG spec requirement that only grayscale profiles may appear in images
@@ -5277,13 +5275,13 @@ Other rules can be inferred by inspecting the libpng source.

 XVI. Y2K Compliance in libpng

-October 29, 2014
+February 17, 2015

 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 1.6.15beta01 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.17beta03 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
--- a/libpng.3
+++ b/libpng.3
@@ -1,6 +1,6 @@
-.TH LIBPNG 3 "October 29, 2014"
+.TH LIBPNG 3 "February 17, 2015"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.15beta01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.17beta03
 .SH SYNOPSIS
 \fB
 #include <png.h>\fP
@@ -504,10 +504,10 @@ 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 1.6.15beta01 - October 29, 2014
+ libpng version 1.6.17beta03 - February 17, 2015
 Updated and distributed by Glenn Randers-Pehrson
 <glennrp at users.sourceforge.net>
- Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ Copyright (c) 1998-2015 Glenn Randers-Pehrson

 This document is released under the libpng license.
 For conditions of distribution and use, see the disclaimer
@@ -515,9 +515,9 @@ libpng-manual.txt - A description on how to use and modify libpng

 Based on:

- libpng versions 0.97, January 1998, through 1.6.15beta01 - October 29, 2014
+ libpng versions 0.97, January 1998, through 1.6.17beta03 - February 17, 2015
 Updated and distributed by Glenn Randers-Pehrson
- Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ Copyright (c) 1998-2015 Glenn Randers-Pehrson

 libpng 1.0 beta 6 - version 0.96 - May 28, 1997
 Updated and distributed by Andreas Dilger
@@ -848,22 +848,23 @@ then only check the bytes (if any) that your program didn't read.
 to replace them with custom functions.  See the discussion under
 Customizing libpng.

-
    FILE *fp = fopen(file_name, "rb");
    if (!fp)
    {
       return (ERROR);
    }

-    fread(header, 1, number, fp);
-    is_png = !png_sig_cmp(header, 0, number);
+    if (fread(header, 1, number, fp) != number)
+    {
+       return (ERROR);
+    }

+    is_png = !png_sig_cmp(header, 0, number);
    if (!is_png)
    {
       return (NOT_PNG);
    }

-
 Next, png_struct and png_info need to be allocated and initialized.  In
 order to ensure that the size of these structures is correct even with a
 dynamically linked libpng, there are functions to initialize and
@@ -1152,15 +1153,12 @@ callback function:

 The PNG specification allows the width and height of an image to be as
 large as 2^(31\-1 (0x7fffffff), or about 2.147 billion rows and columns.
-Since very few applications really need to process such large images,
-we have imposed an arbitrary 1-million limit on rows and columns.
 Larger images will be rejected immediately with a png_error() call. If
-you wish to change this limit, you can use
+you wish to reduce these limits, you can use

   png_set_user_limits(png_ptr, width_max, height_max);

-to set your own limits, or use width_max = height_max = 0x7fffffffL
-to allow all valid dimensions (libpng may reject some very large images
+to set your own limits (libpng may reject some very wide images
 anyway because of potential buffer overflow conditions).

 You should put this statement after you create the PNG structure and
@@ -5541,8 +5539,8 @@ where "rp" indicates a "restricted pointer".
 Error detection in some chunks has improved; in particular the iCCP chunk
 reader now does pretty complete validation of the basic format.  Some bad
 profiles that were previously accepted are now accepted with a warning or
-rejected, depending upon the png_set_benign_errors() setting, in particular the
-very old broken Microsoft/HP 3144-byte sRGB profile.  Starting with
+rejected, depending upon the png_set_benign_errors() setting, in particular
+the very old broken Microsoft/HP 3144-byte sRGB profile.  Starting with
 libpng-1.6.11, recognizing and checking sRGB profiles can be avoided by
 means of

@@ -5552,8 +5550,8 @@ means of
           PNG_OPTION_ON);
    #endif

-It's not a good idea to do this if you are using the "simplified API",
-which needs to be able to recognize an sRGB profile conveyed via the iCCP
+It's not a good idea to do this if you are using the new "simplified API",
+which needs to be able to recognize sRGB profiles conveyed via the iCCP
 chunk.

 The PNG spec requirement that only grayscale profiles may appear in images
@@ -5781,13 +5779,13 @@ Other rules can be inferred by inspecting the libpng source.

 .SH XVI. Y2K Compliance in libpng

-October 29, 2014
+February 17, 2015

 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 1.6.15beta01 are Y2K compliant.  It is my belief that earlier
+upward through 1.6.17beta03 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
@@ -6033,7 +6031,13 @@ the first widely used release:
 1.6.14beta01-07     16    10614  16.so.16.14[.0]
 1.6.14rc01-02       16    10614  16.so.16.14[.0]
 1.6.14              16    10614  16.so.16.14[.0]
- 1.6.15beta01        16    10615  16.so.16.15[.0]
+ 1.6.15beta01-08     16    10615  16.so.16.15[.0]
+ 1.6.15rc01-03       16    10615  16.so.16.15[.0]
+ 1.6.15              16    10615  16.so.16.15[.0]
+ 1.6.16beta01-03     16    10616  16.so.16.16[.0]
+ 1.6.16rc01-02       16    10616  16.so.16.16[.0]
+ 1.6.16              16    10616  16.so.16.16[.0]
+ 1.6.17beta01-03     16    10617  16.so.16.17[.0]

 Henceforth the source version will match the shared-library minor
 and patch numbers; the shared-library major version number will be
@@ -6090,7 +6094,7 @@ possible without all of you.

 Thanks to Frank J. T. Wojcik for helping with the documentation.

-Libpng version 1.6.15beta01 - October 29, 2014:
+Libpng version 1.6.17beta03 - February 17, 2015:
 Initially created in 1995 by Guy Eric Schalnat, then of Group 42, Inc.
 Currently maintained by Glenn Randers-Pehrson (glennrp at users.sourceforge.net).

@@ -6113,7 +6117,7 @@ this sentence.

 This code is released under the libpng license.

-libpng versions 1.2.6, August 15, 2004, through 1.6.15beta01, October 29, 2014, are
+libpng versions 1.2.6, August 15, 2004, through 1.6.17beta03, February 17, 2015, are
 Copyright (c) 2004,2006-2014 Glenn Randers-Pehrson, and are
 distributed according to the same disclaimer and license as libpng-1.2.5
 with the following individual added to the list of Contributing Authors
@@ -6212,7 +6216,7 @@ certification mark of the Open Source Initiative.

 Glenn Randers-Pehrson
 glennrp at users.sourceforge.net
-October 29, 2014
+February 17, 2015

 .\" end of man page

--- a/libpngpf.3
+++ b/libpngpf.3
@@ -1,6 +1,6 @@
-.TH LIBPNGPF 3 "October 29, 2014"
+.TH LIBPNGPF 3 "February 17, 2015"
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.6.15beta01
+libpng \- Portable Network Graphics (PNG) Reference Library 1.6.17beta03
 (private functions)
 .SH SYNOPSIS
 \fB#include \fI"pngpriv.h"
--- a/png.5
+++ b/png.5
@@ -1,4 +1,4 @@
-.TH PNG 5 "October 29, 2014"
+.TH PNG 5 "February 17, 2015"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
--- a/png.c
+++ b/png.c
--- a/png.h
+++ b/png.h
@@ -1,8 +1,8 @@

 /* png.h - header file for PNG reference library
 *
- * libpng version 1.6.15beta01 - October 29, 2014
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * libpng version 1.6.17beta03, February 17, 2015
+ * Copyright (c) 1998-2015 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.)
 *
@@ -11,7 +11,7 @@
 * Authors and maintainers:
 *   libpng versions 0.71, May 1995, through 0.88, January 1996: Guy Schalnat
 *   libpng versions 0.89c, June 1996, through 0.96, May 1997: Andreas Dilger
- *   libpng versions 0.97, January 1998, through 1.6.15beta01 - October 29, 2014: Glenn
+ *   libpng versions 0.97, January 1998, through 1.6.17beta03, February 17, 2015: Glenn
 *   See also "Contributing Authors", below.
 *
 * Note about libpng version numbers:
@@ -206,7 +206,13 @@
 *    1.6.14beta01-07         16    10614  16.so.16.14[.0]
 *    1.6.14rc01-02           16    10614  16.so.16.14[.0]
 *    1.6.14                  16    10614  16.so.16.14[.0]
- *    1.6.15beta01            16    10615  16.so.16.15[.0]
+ *    1.6.15beta01-08         16    10615  16.so.16.15[.0]
+ *    1.6.15rc01-03           16    10615  16.so.16.15[.0]
+ *    1.6.15                  16    10615  16.so.16.15[.0]
+ *    1.6.16beta01-03         16    10616  16.so.16.16[.0]
+ *    1.6.16rc01-02           16    10616  16.so.16.16[.0]
+ *    1.6.16                  16    10616  16.so.16.16[.0]
+ *    1.6.17beta01-03         16    10617  16.so.16.17[.0]
 *
 *   Henceforth the source version will match the shared-library major
 *   and minor numbers; the shared-library major version number will be
@@ -238,8 +244,8 @@
 *
 * This code is released under the libpng license.
 *
- * libpng versions 1.2.6, August 15, 2004, through 1.6.15beta01, October 29, 2014, are
- * Copyright (c) 2004, 2006-2014 Glenn Randers-Pehrson, and are
+ * libpng versions 1.2.6, August 15, 2004, through 1.6.17beta03, February 17, 2015, are
+ * Copyright (c) 2004, 2006-2015 Glenn Randers-Pehrson, and are
 * distributed according to the same disclaimer and license as libpng-1.2.5
 * with the following individual added to the list of Contributing Authors:
 *
@@ -350,13 +356,13 @@
 * Y2K compliance in libpng:
 * =========================
 *
- *    October 29, 2014
+ *    February 17, 2015
 *
 *    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 1.6.15beta01 are Y2K compliant.  It is my belief that
+ *    upward through 1.6.17beta03 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
@@ -418,9 +424,9 @@
 */

 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.6.15beta01"
+#define PNG_LIBPNG_VER_STRING "1.6.17beta03"
 #define PNG_HEADER_VERSION_STRING \
-     " libpng version 1.6.15beta01 - October 29, 2014\n"
+     " libpng version 1.6.17beta03 - February 17, 2015\n"

 #define PNG_LIBPNG_VER_SONUM   16
 #define PNG_LIBPNG_VER_DLLNUM  16
@@ -428,13 +434,13 @@
 /* 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 15
+#define PNG_LIBPNG_VER_RELEASE 17

 /* 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  03

 /* Release Status */
 #define PNG_LIBPNG_BUILD_ALPHA    1
@@ -459,7 +465,7 @@
 * 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 10615 /* 1.6.15 */
+#define PNG_LIBPNG_VER 10617 /* 1.6.17 */

 /* Library configuration: these options cannot be changed after
 * the library has been built.
@@ -564,7 +570,7 @@ 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_15beta01;
+typedef char* png_libpng_version_1_6_17beta03;

 /* Basic control structions.  Read libpng-manual.txt or libpng.3 for more info.
 *
@@ -1177,7 +1183,7 @@ PNG_EXPORT(24, void, png_convert_from_struct_tm, (png_timep ptime,

 /* Convert from time_t to png_time.  Uses gmtime() */
 PNG_EXPORT(25, void, png_convert_from_time_t, (png_timep ptime, time_t ttime));
-#endif /* PNG_CONVERT_tIME_SUPPORTED */
+#endif /* CONVERT_tIME */

 #ifdef PNG_READ_EXPAND_SUPPORTED
 /* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
@@ -1383,7 +1389,7 @@ PNG_EXPORT(39, void, png_set_filler, (png_structrp png_ptr, png_uint_32 filler,
 /* Add an alpha byte to 8-bit Gray or 24-bit RGB images. */
 PNG_EXPORT(40, void, png_set_add_alpha, (png_structrp png_ptr,
    png_uint_32 filler, int flags));
-#endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
+#endif /* READ_FILLER || WRITE_FILLER */

 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
 /* Swap bytes in 16-bit depth files. */
@@ -1647,7 +1653,7 @@ PNG_FIXED_EXPORT(209, void, png_set_filter_heuristics_fixed,
    (png_structrp png_ptr, int heuristic_method, int num_weights,
    png_const_fixed_point_p filter_weights,
    png_const_fixed_point_p filter_costs))
-#endif /*  PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+#endif /* WRITE_WEIGHTED_FILTER */

 /* Heuristic used for row filter selection.  These defines should NOT be
 * changed.
@@ -1703,7 +1709,7 @@ PNG_EXPORT(225, void, png_set_text_compression_window_bits,

 PNG_EXPORT(226, void, png_set_text_compression_method, (png_structrp png_ptr,
    int method));
-#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */

 /* These next functions are called for input/output, memory, and error
 * handling.  They are in the file pngrio.c, pngwio.c, and pngerror.c,
@@ -1870,7 +1876,7 @@ PNG_EXPORT(220, png_uint_32, png_process_data_skip, (png_structrp));
 */
 PNG_EXPORT(93, void, png_progressive_combine_row, (png_const_structrp png_ptr,
    png_bytep old_row, png_const_bytep new_row));
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+#endif /* PROGRESSIVE_READ */

 PNG_EXPORTA(94, png_voidp, png_malloc, (png_const_structrp png_ptr,
    png_alloc_size_t size), PNG_ALLOCATED);
@@ -2071,7 +2077,7 @@ PNG_EXPORT(128, png_int_32, png_get_x_offset_microns,
 PNG_EXPORT(129, png_int_32, png_get_y_offset_microns,
    (png_const_structrp png_ptr, png_const_inforp info_ptr));

-#endif /* PNG_EASY_ACCESS_SUPPORTED */
+#endif /* EASY_ACCESS */

 #ifdef PNG_READ_SUPPORTED
 /* Returns pointer to signature string read from PNG header */
@@ -2323,7 +2329,7 @@ PNG_FIXED_EXPORT(213, void, png_set_sCAL_fixed, (png_const_structrp png_ptr,
 PNG_EXPORT(171, void, png_set_sCAL_s, (png_const_structrp png_ptr,
    png_inforp info_ptr, int unit,
    png_const_charp swidth, png_const_charp sheight));
-#endif /* PNG_sCAL_SUPPORTED */
+#endif /* sCAL */

 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
 /* Provide the default handling for all unknown chunks or, optionally, for
@@ -2551,8 +2557,8 @@ PNG_FIXED_EXPORT(212, png_fixed_point, png_get_y_offset_inches_fixed,
 PNG_EXPORT(198, png_uint_32, png_get_pHYs_dpi, (png_const_structrp png_ptr,
    png_const_inforp info_ptr, png_uint_32 *res_x, png_uint_32 *res_y,
    int *unit_type));
-#  endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
+#  endif /* pHYs */
+#endif  /* INCH_CONVERSIONS */

 /* Added in libpng-1.4.0 */
 #ifdef PNG_IO_STATE_SUPPORTED
@@ -2575,7 +2581,7 @@ PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
 #  define PNG_IO_CHUNK_CRC   0x0080   /* currently at the chunk crc */
 #  define PNG_IO_MASK_OP     0x000f   /* current operation: reading/writing */
 #  define PNG_IO_MASK_LOC    0x00f0   /* current location: sig/hdr/data/crc */
-#endif /* ?PNG_IO_STATE_SUPPORTED */
+#endif /* IO_STATE */

 /* Interlace support.  The following macros are always defined so that if
 * libpng interlace handling is turned off the macros may be used to handle
@@ -2679,7 +2685,7 @@ PNG_EXPORT(216, png_uint_32, png_get_io_chunk_type,
     (composite) = (png_uint_16)(((png_uint_32)(fg) * (png_uint_32)(alpha) + \
     (png_uint_32)(bg)*(png_uint_32)(65535 - (png_uint_32)(alpha)) +         \
     32767) / 65535)
-#endif /* PNG_READ_COMPOSITE_NODIV_SUPPORTED */
+#endif /* READ_COMPOSITE_NODIV */

 #ifdef PNG_READ_INT_FUNCTIONS_SUPPORTED
 PNG_EXPORT(201, png_uint_32, png_get_uint_32, (png_const_bytep buf));
@@ -3107,7 +3113,7 @@ PNG_EXPORT(234, int, png_image_begin_read_from_file, (png_imagep image,
 PNG_EXPORT(235, int, png_image_begin_read_from_stdio, (png_imagep image,
   FILE* file));
   /* The PNG header is read from the stdio FILE object. */
-#endif /* PNG_STDIO_SUPPORTED */
+#endif /* STDIO */

 PNG_EXPORT(236, int, png_image_begin_read_from_memory, (png_imagep image,
   png_const_voidp memory, png_size_t size));
@@ -3152,7 +3158,7 @@ PNG_EXPORT(238, void, png_image_free, (png_imagep image));
   /* Free any data allocated by libpng in image->opaque, setting the pointer to
    * NULL.  May be called at any time after the structure is initialized.
    */
-#endif /* PNG_SIMPLIFIED_READ_SUPPORTED */
+#endif /* SIMPLIFIED_READ */

 #ifdef PNG_SIMPLIFIED_WRITE_SUPPORTED
 #ifdef PNG_STDIO_SUPPORTED
@@ -3198,12 +3204,12 @@ PNG_EXPORT(240, int, png_image_write_to_stdio, (png_imagep image, FILE *file,
 *
 * Note that the write API does not support interlacing or sub-8-bit pixels.
 */
-#endif /* PNG_STDIO_SUPPORTED */
-#endif /* PNG_SIMPLIFIED_WRITE_SUPPORTED */
+#endif /* STDIO */
+#endif /* SIMPLIFIED_WRITE */
 /*******************************************************************************
 *  END OF SIMPLIFIED API
 ******************************************************************************/
-#endif /* PNG_SIMPLIFIED_{READ|WRITE}_SUPPORTED */
+#endif /* SIMPLIFIED_{READ|WRITE} */

 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
 PNG_EXPORT(242, void, png_set_check_for_invalid_index,
@@ -3251,7 +3257,7 @@ PNG_EXPORT(243, int, png_get_palette_max, (png_const_structp png_ptr,

 PNG_EXPORT(244, int, png_set_option, (png_structrp png_ptr, int option,
   int onoff));
-#endif /* PNG_SET_OPTION_SUPPORTED */
+#endif /* SET_OPTION */

 /*******************************************************************************
 *  END OF HARDWARE AND SOFTWARE OPTIONS
--- a/pngconf.h
+++ b/pngconf.h
@@ -1,9 +1,9 @@

 /* pngconf.h - machine configurable file for libpng
 *
- * libpng version 1.6.15beta01 - October 29, 2014
+ * libpng version 1.6.17beta03, (PENDING RELEASE)
 *
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2015 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.)
 *
@@ -22,26 +22,6 @@
 #ifndef PNGCONF_H
 #define PNGCONF_H

-/* To do: Do all of this in scripts/pnglibconf.dfa */
-#ifdef PNG_SAFE_LIMITS_SUPPORTED
-#  ifdef PNG_USER_WIDTH_MAX
-#    undef PNG_USER_WIDTH_MAX
-#    define PNG_USER_WIDTH_MAX 1000000L
-#  endif
-#  ifdef PNG_USER_HEIGHT_MAX
-#    undef PNG_USER_HEIGHT_MAX
-#    define PNG_USER_HEIGHT_MAX 1000000L
-#  endif
-#  ifdef PNG_USER_CHUNK_MALLOC_MAX
-#    undef PNG_USER_CHUNK_MALLOC_MAX
-#    define PNG_USER_CHUNK_MALLOC_MAX 4000000L
-#  endif
-#  ifdef PNG_USER_CHUNK_CACHE_MAX
-#    undef PNG_USER_CHUNK_CACHE_MAX
-#    define PNG_USER_CHUNK_CACHE_MAX 128
-#  endif
-#endif
-
 #ifndef PNG_BUILDING_SYMBOL_TABLE /* else includes may cause problems */

 /* From libpng 1.6.0 libpng requires an ANSI X3.159-1989 ("ISOC90") compliant C
--- a/pngerror.c
+++ b/pngerror.c
@@ -1,7 +1,7 @@

 /* pngerror.c - stub functions for i/o and memory allocation
 *
- * Last changed in libpng 1.6.13 [August 21, 2014]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -27,7 +27,7 @@ static PNG_FUNCTION(void, png_default_error,PNGARG((png_const_structrp png_ptr,
 static void /* PRIVATE */
 png_default_warning PNGARG((png_const_structrp png_ptr,
   png_const_charp warning_message));
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */

 /* This function is called whenever there is a fatal error.  This function
 * should not be changed.  If there is a need to handle errors differently,
@@ -43,8 +43,8 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
   char msg[16];
   if (png_ptr != NULL)
   {
-      if (png_ptr->flags&
-         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+      if ((png_ptr->flags &
+         (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0
      {
         if (*error_message == PNG_LITERAL_SHARP)
         {
@@ -54,7 +54,7 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),
               if (error_message[offset] == ' ')
                  break;

-            if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+            if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0)
            {
               int i;
               for (i = 0; i < offset - 1; i++)
@@ -69,7 +69,7 @@ png_error,(png_const_structrp png_ptr, png_const_charp error_message),

      else
      {
-         if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT)
+         if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0)
         {
            msg[0] = '0';
            msg[1] = '\0';
@@ -103,7 +103,7 @@ png_err,(png_const_structrp png_ptr),PNG_NORETURN)
      use the default handler, which will not return. */
   png_default_error(png_ptr, "");
 }
-#endif /* PNG_ERROR_TEXT_SUPPORTED */
+#endif /* ERROR_TEXT */

 /* Utility to safely appends strings to a buffer.  This never errors out so
 * error checking is not required in the caller.
@@ -152,7 +152,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
         case PNG_NUMBER_FORMAT_fixed:
            /* Needs five digits (the fraction) */
            mincount = 5;
-            if (output || number % 10 != 0)
+            if (output != 0 || number % 10 != 0)
            {
               *--end = digits[number % 10];
               output = 1;
@@ -189,7 +189,7 @@ png_format_number(png_const_charp start, png_charp end, int format,
      ++count;

      /* Float a fixed number here: */
-      if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start)
+      if ((format == PNG_NUMBER_FORMAT_fixed) && (count == 5) && (end > start))
      {
         /* End of the fraction, but maybe nothing was output?  In that case
          * drop the decimal point.  If the number is a true zero handle that
@@ -219,8 +219,8 @@ png_warning(png_const_structrp png_ptr, png_const_charp warning_message)
   if (png_ptr != NULL)
   {
 #ifdef PNG_ERROR_NUMBERS_SUPPORTED
-   if (png_ptr->flags&
-       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))
+   if ((png_ptr->flags &
+       (PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0)
 #endif
      {
         if (*warning_message == PNG_LITERAL_SHARP)
@@ -355,13 +355,13 @@ png_formatted_warning(png_const_structrp png_ptr, png_warning_parameters p,
    */
   png_warning(png_ptr, msg);
 }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */

 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
 void PNGAPI
 png_benign_error(png_const_structrp png_ptr, png_const_charp error_message)
 {
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
+   if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0)
   {
 #     ifdef PNG_READ_SUPPORTED
         if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 &&
@@ -391,7 +391,7 @@ 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)
+  if ((png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN) != 0)
     png_warning(png_ptr, error_message);
  else
     png_error(png_ptr, error_message);
@@ -404,7 +404,7 @@ 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)
+  if ((png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN) != 0)
     png_warning(png_ptr, error_message);
  else
     png_error(png_ptr, error_message);
@@ -442,7 +442,7 @@ png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp
      int c = (int)(chunk_name >> ishift) & 0xff;

      ishift -= 8;
-      if (isnonalpha(c))
+      if (isnonalpha(c) != 0)
      {
         buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET;
         buffer[iout++] = png_digit[(c & 0xf0) >> 4];
@@ -473,7 +473,7 @@ png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp
      buffer[iout] = '\0';
   }
 }
-#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */
+#endif /* WARNINGS || ERROR_TEXT */

 #if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
 PNG_FUNCTION(void,PNGAPI
@@ -490,7 +490,7 @@ png_chunk_error,(png_const_structrp png_ptr, png_const_charp error_message),
      png_error(png_ptr, msg);
   }
 }
-#endif /* PNG_READ_SUPPORTED && PNG_ERROR_TEXT_SUPPORTED */
+#endif /* READ && ERROR_TEXT */

 #ifdef PNG_WARNINGS_SUPPORTED
 void PNGAPI
@@ -506,7 +506,7 @@ png_chunk_warning(png_const_structrp png_ptr, png_const_charp warning_message)
      png_warning(png_ptr, msg);
   }
 }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */

 #ifdef PNG_READ_SUPPORTED
 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
@@ -514,7 +514,7 @@ void PNGAPI
 png_chunk_benign_error(png_const_structrp png_ptr, png_const_charp
    error_message)
 {
-   if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN)
+   if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0)
      png_chunk_warning(png_ptr, error_message);

   else
@@ -525,7 +525,7 @@ png_chunk_benign_error(png_const_structrp png_ptr, png_const_charp
 #  endif
 }
 #endif
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ */

 void /* PRIVATE */
 png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
@@ -538,7 +538,7 @@ png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
    * unconditionally does the right thing.
    */
 #  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
 #  endif

 #  ifdef PNG_READ_SUPPORTED
@@ -552,7 +552,7 @@ png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
 #  endif

 #  if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED)
-      else if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
+      else if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
 #  endif

 #  ifdef PNG_WRITE_SUPPORTED
@@ -577,11 +577,12 @@ png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN)
   char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT];
   memcpy(msg, fixed_message, fixed_message_ln);
   iin = 0;
-   if (name != NULL) while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0)
-   {
-      msg[fixed_message_ln + iin] = name[iin];
-      ++iin;
-   }
+   if (name != NULL)
+      while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0)
+      {
+         msg[fixed_message_ln + iin] = name[iin];
+         ++iin;
+      }
   msg[fixed_message_ln + iin] = 0;
   png_error(png_ptr, msg);
 }
@@ -757,7 +758,8 @@ PNG_FUNCTION(void,PNGAPI
 png_longjmp,(png_const_structrp png_ptr, int val),PNG_NORETURN)
 {
 #ifdef PNG_SETJMP_SUPPORTED
-   if (png_ptr && png_ptr->longjmp_fn && png_ptr->jmp_buf_ptr)
+   if (png_ptr != NULL && png_ptr->longjmp_fn != NULL &&
+       png_ptr->jmp_buf_ptr != NULL)
      png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val);
 #else
   PNG_UNUSED(png_ptr)
@@ -822,7 +824,7 @@ png_default_warning(png_const_structrp png_ptr, png_const_charp warning_message)
 #endif
   PNG_UNUSED(png_ptr) /* Make compiler happy */
 }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */

 /* This function is called when the application wants to use another method
 * of handling errors and warnings.  Note that the error function MUST NOT
@@ -957,5 +959,5 @@ png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg)

   return result;
 }
-#endif /* SIMPLIFIED READ/WRITE */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* SIMPLIFIED READ || SIMPLIFIED_WRITE */
+#endif /* READ || WRITE */
--- a/pngget.c
+++ b/pngget.c
@@ -1,7 +1,7 @@

 /* pngget.c - retrieval of values from info struct
 *
- * Last changed in libpng 1.6.11 [June 5, 2014]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -116,7 +116,8 @@ png_get_x_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp
   info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
      {
         png_debug1(1, "in %s retrieval function",
             "png_get_x_pixels_per_meter");
@@ -137,7 +138,8 @@ png_get_y_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp
    info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
   {
      png_debug1(1, "in %s retrieval function",
          "png_get_y_pixels_per_meter");
@@ -157,7 +159,8 @@ png_uint_32 PNGAPI
 png_get_pixels_per_meter(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "png_get_pixels_per_meter");

@@ -179,7 +182,8 @@ png_get_pixel_aspect_ratio(png_const_structrp png_ptr, png_const_inforp
   info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "png_get_aspect_ratio");

@@ -202,10 +206,11 @@ png_get_pixel_aspect_ratio_fixed(png_const_structrp png_ptr,
    png_const_inforp info_ptr)
 {
 #ifdef PNG_READ_pHYs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs)
-       && info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0
-       && info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX
-       && info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0 &&
+       info_ptr->x_pixels_per_unit > 0 && info_ptr->y_pixels_per_unit > 0 &&
+       info_ptr->x_pixels_per_unit <= PNG_UINT_31_MAX &&
+       info_ptr->y_pixels_per_unit <= PNG_UINT_31_MAX)
   {
      png_fixed_point res;

@@ -215,7 +220,7 @@ png_get_pixel_aspect_ratio_fixed(png_const_structrp png_ptr,
       * range of 0..2^31-1; otherwise the cast might overflow.
       */
      if (png_muldiv(&res, (png_int_32)info_ptr->y_pixels_per_unit, PNG_FP_1,
-          (png_int_32)info_ptr->x_pixels_per_unit))
+          (png_int_32)info_ptr->x_pixels_per_unit) != 0)
         return res;
   }
 #else
@@ -231,7 +236,8 @@ png_int_32 PNGAPI
 png_get_x_offset_microns(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "png_get_x_offset_microns");

@@ -250,7 +256,8 @@ png_int_32 PNGAPI
 png_get_y_offset_microns(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "png_get_y_offset_microns");

@@ -269,7 +276,8 @@ png_int_32 PNGAPI
 png_get_x_offset_pixels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "png_get_x_offset_pixels");

@@ -288,7 +296,8 @@ png_int_32 PNGAPI
 png_get_y_offset_pixels(png_const_structrp png_ptr, png_const_inforp info_ptr)
 {
 #ifdef PNG_oFFs_SUPPORTED
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "png_get_y_offset_pixels");

@@ -328,7 +337,7 @@ ppi_from_ppm(png_uint_32 ppm)
    */
   png_fixed_point result;
   if (ppm <= PNG_UINT_31_MAX && png_muldiv(&result, (png_int_32)ppm, 127,
-       5000))
+       5000) != 0)
      return result;

   /* Overflow. */
@@ -414,7 +423,8 @@ png_get_pHYs_dpi(png_const_structrp png_ptr, png_const_inforp info_ptr,
 {
   png_uint_32 retval = 0;

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
   {
      png_debug1(1, "in %s retrieval function", "pHYs");

@@ -445,12 +455,12 @@ png_get_pHYs_dpi(png_const_structrp png_ptr, png_const_inforp info_ptr,

   return (retval);
 }
-#endif /* PNG_pHYs_SUPPORTED */
-#endif  /* PNG_INCH_CONVERSIONS_SUPPORTED */
+#endif /* pHYs */
+#endif  /* INCH_CONVERSIONS */

 /* png_get_channels really belongs in here, too, but it's been around longer */

-#endif  /* PNG_EASY_ACCESS_SUPPORTED */
+#endif  /* EASY_ACCESS */


 png_byte PNGAPI
@@ -478,8 +488,9 @@ png_uint_32 PNGAPI
 png_get_bKGD(png_const_structrp png_ptr, png_inforp info_ptr,
   png_color_16p *background)
 {
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
-       && background != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_bKGD) != 0 &&
+       background != NULL)
   {
      png_debug1(1, "in %s retrieval function", "bKGD");

@@ -509,7 +520,7 @@ png_get_cHRM(png_const_structrp png_ptr, png_const_inforp info_ptr,
    * consistent.
    */
   if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
   {
      png_debug1(1, "in %s retrieval function", "cHRM");

@@ -550,7 +561,7 @@ png_get_cHRM_XYZ(png_const_structrp png_ptr, png_const_inforp info_ptr,
   double *blue_Z)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
   {
      png_debug1(1, "in %s retrieval function", "cHRM_XYZ(float)");

@@ -598,7 +609,7 @@ png_get_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
    png_fixed_point *int_blue_Z)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
   {
      png_debug1(1, "in %s retrieval function", "cHRM_XYZ");

@@ -635,7 +646,7 @@ png_get_cHRM_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
   png_debug1(1, "in %s retrieval function", "cHRM");

   if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS))
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_ENDPOINTS) != 0)
   {
      if (white_x != NULL)
         *white_x = info_ptr->colorspace.end_points_xy.whitex;
@@ -670,7 +681,7 @@ png_get_gAMA_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
   png_debug1(1, "in %s retrieval function", "gAMA");

   if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) &&
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
      file_gamma != NULL)
   {
      *file_gamma = info_ptr->colorspace.gamma;
@@ -689,7 +700,7 @@ png_get_gAMA(png_const_structrp png_ptr, png_const_inforp info_ptr,
   png_debug1(1, "in %s retrieval function", "gAMA(float)");

   if (png_ptr != NULL && info_ptr != NULL &&
-      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) &&
+      (info_ptr->colorspace.flags & PNG_COLORSPACE_HAVE_GAMMA) != 0 &&
      file_gamma != NULL)
   {
      *file_gamma = png_float(png_ptr, info_ptr->colorspace.gamma,
@@ -709,8 +720,8 @@ png_get_sRGB(png_const_structrp png_ptr, png_const_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "sRGB");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
-       && file_srgb_intent != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+      (info_ptr->valid & PNG_INFO_sRGB) != 0 && file_srgb_intent != NULL)
   {
      *file_srgb_intent = info_ptr->colorspace.rendering_intent;
      return (PNG_INFO_sRGB);
@@ -728,9 +739,10 @@ png_get_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "iCCP");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP)
-       && name != NULL && compression_type != NULL && profile != NULL &&
-		 proflen != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_iCCP) != 0 &&
+       name != NULL && compression_type != NULL && profile != NULL &&
+           proflen != NULL)
   {
      *name = info_ptr->iccp_name;
      *profile = info_ptr->iccp_profile;
@@ -768,8 +780,8 @@ png_get_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "hIST");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
-       && hist != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_hIST) != 0 && hist != NULL)
   {
      *hist = info_ptr->hist;
      return (PNG_INFO_hIST);
@@ -824,8 +836,9 @@ png_get_oFFs(png_const_structrp png_ptr, png_const_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "oFFs");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
-       && offset_x != NULL && offset_y != NULL && unit_type != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_oFFs) != 0 &&
+       offset_x != NULL && offset_y != NULL && unit_type != NULL)
   {
      *offset_x = info_ptr->x_offset;
      *offset_y = info_ptr->y_offset;
@@ -845,8 +858,9 @@ png_get_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "pCAL");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL)
-       && purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_pCAL) != 0 &&
+       purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
       nparams != NULL && units != NULL && params != NULL)
   {
      *purpose = info_ptr->pcal_purpose;
@@ -872,7 +886,7 @@ png_get_sCAL_fixed(png_const_structrp png_ptr, png_const_inforp info_ptr,
    int *unit, png_fixed_point *width, png_fixed_point *height)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
+       (info_ptr->valid & PNG_INFO_sCAL) != 0)
   {
      *unit = info_ptr->scal_unit;
      /*TODO: make this work without FP support; the API is currently eliminated
@@ -895,7 +909,7 @@ png_get_sCAL(png_const_structrp png_ptr, png_const_inforp info_ptr,
    int *unit, double *width, double *height)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
+       (info_ptr->valid & PNG_INFO_sCAL) != 0)
   {
      *unit = info_ptr->scal_unit;
      *width = atof(info_ptr->scal_s_width);
@@ -911,7 +925,7 @@ png_get_sCAL_s(png_const_structrp png_ptr, png_const_inforp info_ptr,
    int *unit, png_charpp width, png_charpp height)
 {
   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_sCAL))
+       (info_ptr->valid & PNG_INFO_sCAL) != 0)
   {
      *unit = info_ptr->scal_unit;
      *width = info_ptr->scal_s_width;
@@ -933,7 +947,7 @@ png_get_pHYs(png_const_structrp png_ptr, png_const_inforp info_ptr,
   png_debug1(1, "in %s retrieval function", "pHYs");

   if (png_ptr != NULL && info_ptr != NULL &&
-       (info_ptr->valid & PNG_INFO_pHYs))
+       (info_ptr->valid & PNG_INFO_pHYs) != 0)
   {
      if (res_x != NULL)
      {
@@ -964,8 +978,8 @@ png_get_PLTE(png_const_structrp png_ptr, png_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "PLTE");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_PLTE)
-       && palette != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_PLTE) != 0 && palette != NULL)
   {
      *palette = info_ptr->palette;
      *num_palette = info_ptr->num_palette;
@@ -983,8 +997,8 @@ png_get_sBIT(png_const_structrp png_ptr, png_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "sBIT");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT)
-       && sig_bit != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_sBIT) != 0 && sig_bit != NULL)
   {
      *sig_bit = &(info_ptr->sig_bit);
      return (PNG_INFO_sBIT);
@@ -1027,8 +1041,8 @@ png_get_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
 {
   png_debug1(1, "in %s retrieval function", "tIME");

-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME)
-       && mod_time != NULL)
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_tIME) != 0 && mod_time != NULL)
   {
      *mod_time = &(info_ptr->mod_time);
      return (PNG_INFO_tIME);
@@ -1044,7 +1058,8 @@ png_get_tRNS(png_const_structrp png_ptr, png_inforp info_ptr,
    png_bytep *trans_alpha, int *num_trans, png_color_16p *trans_color)
 {
   png_uint_32 retval = 0;
-   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
+   if (png_ptr != NULL && info_ptr != NULL &&
+       (info_ptr->valid & PNG_INFO_tRNS) != 0)
   {
      png_debug1(1, "in %s retrieval function", "tRNS");

@@ -1120,21 +1135,21 @@ png_get_compression_buffer_size(png_const_structrp png_ptr)
   if (png_ptr == NULL)
      return 0;

-#  ifdef PNG_WRITE_SUPPORTED
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
-#  endif
+#ifdef PNG_WRITE_SUPPORTED
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
+#endif
   {
-#     ifdef PNG_SEQUENTIAL_READ_SUPPORTED
+#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
         return png_ptr->IDAT_read_size;
-#     else
+#else
         return PNG_IDAT_READ_SIZE;
-#     endif
+#endif
   }

-#  ifdef PNG_WRITE_SUPPORTED
+#ifdef PNG_WRITE_SUPPORTED
      else
         return png_ptr->zbuffer_size;
-#  endif
+#endif
 }

 #ifdef PNG_SET_USER_LIMITS_SUPPORTED
@@ -1165,7 +1180,7 @@ png_get_chunk_malloc_max (png_const_structrp png_ptr)
 {
   return (png_ptr ? png_ptr->user_chunk_malloc_max : 0);
 }
-#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+#endif /* SET_USER_LIMITS */

 /* These functions were added to libpng 1.4.0 */
 #ifdef PNG_IO_STATE_SUPPORTED
@@ -1180,7 +1195,7 @@ png_get_io_chunk_type (png_const_structrp png_ptr)
 {
   return png_ptr->chunk_name;
 }
-#endif /* ?PNG_IO_STATE_SUPPORTED */
+#endif /* IO_STATE */

 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
 #  ifdef PNG_GET_PALETTE_MAX_SUPPORTED
@@ -1195,4 +1210,4 @@ png_get_palette_max(png_const_structp png_ptr, png_const_infop info_ptr)
 #  endif
 #endif

-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* READ || WRITE */
--- a/pnginfo.h
+++ b/pnginfo.h
@@ -121,7 +121,7 @@ struct png_info_def
   int num_text; /* number of comments read or comments to write */
   int max_text; /* current size of text array */
   png_textp text; /* array of comments read or comments to write */
-#endif /* PNG_TEXT_SUPPORTED */
+#endif /* TEXT */

 #ifdef PNG_tIME_SUPPORTED
   /* The tIME chunk holds the last time the displayed image data was
--- a/pngmem.c
+++ b/pngmem.c
@@ -1,8 +1,8 @@

 /* pngmem.c - stub functions for memory allocation
 *
- * Last changed in libpng 1.6.8 [December 19, 2013]
- * Copyright (c) 1998-2013 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.15 [November 20, 2014]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
 *
@@ -199,7 +199,7 @@ png_malloc_default,(png_const_structrp png_ptr, png_alloc_size_t size),

   return ret;
 }
-#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* USER_MEM */

 /* This function was added at libpng version 1.2.3.  The png_malloc_warn()
 * function will issue a png_warning and return NULL instead of issuing a
@@ -244,7 +244,7 @@ png_free_default,(png_const_structrp png_ptr, png_voidp ptr),PNG_DEPRECATED)
 {
   if (png_ptr == NULL || ptr == NULL)
      return;
-#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* USER_MEM */

   free(ptr);
 }
@@ -277,5 +277,5 @@ png_get_mem_ptr(png_const_structrp png_ptr)

   return png_ptr->mem_ptr;
 }
-#endif /* PNG_USER_MEM_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* USER_MEM */
+#endif /* READ || WRITE */
--- a/pngpread.c
+++ b/pngpread.c
@@ -1,8 +1,8 @@

 /* pngpread.c - read a png file in push mode
 *
- * Last changed in libpng 1.6.15 [(PENDING RELEASE)]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2015 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.)
 *
@@ -202,7 +202,7 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)
    * sure we have enough data in the buffer for the 4-byte CRC at the
    * end of every chunk (except IDAT, which is handled separately).
    */
-   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+   if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
   {
      png_byte chunk_length[4];
      png_byte chunk_tag[4];
@@ -221,28 +221,28 @@ png_push_read_chunk(png_structrp png_ptr, png_inforp info_ptr)

   if (chunk_name == png_IDAT)
   {
-      if (png_ptr->mode & PNG_AFTER_IDAT)
+      if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
         png_ptr->mode |= PNG_HAVE_CHUNK_AFTER_IDAT;

      /* If we reach an IDAT chunk, this means we have read all of the
       * header chunks, and we can start reading the image (or if this
       * is called after the image has been read - we have an error).
       */
-      if (!(png_ptr->mode & PNG_HAVE_IHDR))
+      if ((png_ptr->mode & PNG_HAVE_IHDR) == 0)
         png_error(png_ptr, "Missing IHDR before IDAT");

      else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-          !(png_ptr->mode & PNG_HAVE_PLTE))
+          (png_ptr->mode & PNG_HAVE_PLTE) == 0)
         png_error(png_ptr, "Missing PLTE before IDAT");

      png_ptr->mode |= PNG_HAVE_IDAT;
      png_ptr->process_mode = PNG_READ_IDAT_MODE;

-      if (!(png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+      if ((png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) == 0)
         if (png_ptr->push_length == 0)
            return;

-      if (png_ptr->mode & PNG_AFTER_IDAT)
+      if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
         png_benign_error(png_ptr, "Too many IDATs found");
   }

@@ -449,7 +449,7 @@ png_push_crc_skip(png_structrp png_ptr, png_uint_32 skip)
 void /* PRIVATE */
 png_push_crc_finish(png_structrp png_ptr)
 {
-   if (png_ptr->skip_length && png_ptr->save_buffer_size)
+   if (png_ptr->skip_length != 0 && png_ptr->save_buffer_size != 0)
   {
      png_size_t save_size = png_ptr->save_buffer_size;
      png_uint_32 skip_length = png_ptr->skip_length;
@@ -473,7 +473,7 @@ png_push_crc_finish(png_structrp png_ptr)
      png_ptr->save_buffer_size -= save_size;
      png_ptr->save_buffer_ptr += save_size;
   }
-   if (png_ptr->skip_length && png_ptr->current_buffer_size)
+   if (png_ptr->skip_length != 0 && png_ptr->current_buffer_size != 0)
   {
      png_size_t save_size = png_ptr->current_buffer_size;
      png_uint_32 skip_length = png_ptr->skip_length;
@@ -494,7 +494,7 @@ png_push_crc_finish(png_structrp png_ptr)
      png_ptr->current_buffer_size -= save_size;
      png_ptr->current_buffer_ptr += save_size;
   }
-   if (!png_ptr->skip_length)
+   if (png_ptr->skip_length == 0)
   {
      PNG_PUSH_SAVE_BUFFER_IF_LT(4)
      png_crc_finish(png_ptr, 0);
@@ -511,7 +511,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
      return;

   ptr = buffer;
-   if (png_ptr->save_buffer_size)
+   if (png_ptr->save_buffer_size != 0)
   {
      png_size_t save_size;

@@ -528,7 +528,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
      png_ptr->save_buffer_size -= save_size;
      png_ptr->save_buffer_ptr += save_size;
   }
-   if (length && png_ptr->current_buffer_size)
+   if (length != 0 && png_ptr->current_buffer_size != 0)
   {
      png_size_t save_size;

@@ -548,7 +548,7 @@ png_push_fill_buffer(png_structp png_ptr, png_bytep buffer, png_size_t length)
 void /* PRIVATE */
 png_push_save_buffer(png_structrp png_ptr)
 {
-   if (png_ptr->save_buffer_size)
+   if (png_ptr->save_buffer_size != 0)
   {
      if (png_ptr->save_buffer_ptr != png_ptr->save_buffer)
      {
@@ -617,7 +617,7 @@ png_push_restore_buffer(png_structrp png_ptr, png_bytep buffer,
 void /* PRIVATE */
 png_push_read_IDAT(png_structrp png_ptr)
 {
-   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
+   if ((png_ptr->mode & PNG_HAVE_CHUNK_HEADER) == 0)
   {
      png_byte chunk_length[4];
      png_byte chunk_tag[4];
@@ -635,7 +635,7 @@ png_push_read_IDAT(png_structrp png_ptr)
      {
         png_ptr->process_mode = PNG_READ_CHUNK_MODE;

-         if (!(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+         if ((png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
            png_error(png_ptr, "Not enough compressed data");

         return;
@@ -644,7 +644,7 @@ png_push_read_IDAT(png_structrp png_ptr)
      png_ptr->idat_size = png_ptr->push_length;
   }

-   if (png_ptr->idat_size && png_ptr->save_buffer_size)
+   if (png_ptr->idat_size != 0 && png_ptr->save_buffer_size != 0)
   {
      png_size_t save_size = png_ptr->save_buffer_size;
      png_uint_32 idat_size = png_ptr->idat_size;
@@ -671,7 +671,7 @@ png_push_read_IDAT(png_structrp png_ptr)
      png_ptr->save_buffer_ptr += save_size;
   }

-   if (png_ptr->idat_size && png_ptr->current_buffer_size)
+   if (png_ptr->idat_size != 0 && png_ptr->current_buffer_size != 0)
   {
      png_size_t save_size = png_ptr->current_buffer_size;
      png_uint_32 idat_size = png_ptr->idat_size;
@@ -696,7 +696,7 @@ png_push_read_IDAT(png_structrp png_ptr)
      png_ptr->current_buffer_size -= save_size;
      png_ptr->current_buffer_ptr += save_size;
   }
-   if (!png_ptr->idat_size)
+   if (png_ptr->idat_size == 0)
   {
      PNG_PUSH_SAVE_BUFFER_IF_LT(4)
      png_crc_finish(png_ptr, 0);
@@ -726,7 +726,7 @@ png_process_IDAT_data(png_structrp png_ptr, png_bytep buffer,
    * or the stream marked as finished.
    */
   while (png_ptr->zstream.avail_in > 0 &&
-      !(png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED))
+      (png_ptr->flags & PNG_FLAG_ZSTREAM_ENDED) == 0)
   {
      int ret;

@@ -843,7 +843,7 @@ png_push_process_row(png_structrp png_ptr)
   memcpy(png_ptr->prev_row, png_ptr->row_buf, row_info.rowbytes + 1);

 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
-   if (png_ptr->transformations)
+   if (png_ptr->transformations != 0)
      png_do_read_transformations(png_ptr, &row_info);
 #endif

@@ -861,7 +861,8 @@ png_push_process_row(png_structrp png_ptr)

 #ifdef PNG_READ_INTERLACING_SUPPORTED
   /* Expand interlaced rows to full size */
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   if (png_ptr->interlaced != 0 &&
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
   {
      if (png_ptr->pass < 6)
         png_do_read_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass,
@@ -1035,6 +1036,7 @@ png_push_process_row(png_structrp png_ptr)
      }
   }
   else
+#endif
   {
      png_push_have_row(png_ptr, png_ptr->row_buf + 1);
      png_read_push_finish_row(png_ptr);
@@ -1044,6 +1046,7 @@ png_push_process_row(png_structrp png_ptr)
 void /* PRIVATE */
 png_read_push_finish_row(png_structrp png_ptr)
 {
+#ifdef PNG_READ_INTERLACING_SUPPORTED
   /* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */

   /* Start of interlace block */
@@ -1068,7 +1071,8 @@ png_read_push_finish_row(png_structrp png_ptr)
   if (png_ptr->row_number < png_ptr->num_rows)
      return;

-   if (png_ptr->interlaced)
+#ifdef PNG_READ_INTERLACING_SUPPORTED
+   if (png_ptr->interlaced != 0)
   {
      png_ptr->row_number = 0;
      memset(png_ptr->prev_row, 0, png_ptr->rowbytes + 1);
@@ -1092,7 +1096,7 @@ png_read_push_finish_row(png_structrp png_ptr)
             png_pass_start[png_ptr->pass]) /
             png_pass_inc[png_ptr->pass];

-         if (png_ptr->transformations & PNG_INTERLACE)
+         if ((png_ptr->transformations & PNG_INTERLACE) != 0)
            break;

         png_ptr->num_rows = (png_ptr->height +
@@ -1102,6 +1106,7 @@ png_read_push_finish_row(png_structrp png_ptr)

      } while (png_ptr->iwidth == 0 || png_ptr->num_rows == 0);
   }
+#endif /* READ_INTERLACING */
 }

 void /* PRIVATE */
@@ -1126,6 +1131,7 @@ png_push_have_row(png_structrp png_ptr, png_bytep row)
         (int)png_ptr->pass);
 }

+#ifdef PNG_READ_INTERLACING_SUPPORTED
 void PNGAPI
 png_progressive_combine_row(png_const_structrp png_ptr, png_bytep old_row,
    png_const_bytep new_row)
@@ -1140,6 +1146,7 @@ png_progressive_combine_row(png_const_structrp png_ptr, png_bytep old_row,
   if (new_row != NULL)
      png_combine_row(png_ptr, old_row, 1/*blocky display*/);
 }
+#endif /* READ_INTERLACING */

 void PNGAPI
 png_set_progressive_read_fn(png_structrp png_ptr, png_voidp progressive_ptr,
@@ -1164,4 +1171,4 @@ png_get_progressive_ptr(png_const_structrp png_ptr)

   return png_ptr->io_ptr;
 }
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+#endif /* PROGRESSIVE_READ */
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -2,11 +2,11 @@
 /* pngpriv.h - private declarations for use inside libpng
 *
 * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Copyright (c) 1998-2015 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.)
 *
- * Last changed in libpng 1.6.10 [March 6, 1014]]
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -172,7 +172,7 @@
          */
 #        define PNG_ARM_NEON_IMPLEMENTATION 2
 #     endif /* __ARM_NEON__ */
-#  endif /* !defined PNG_ARM_NEON_IMPLEMENTATION */
+#  endif /* !PNG_ARM_NEON_IMPLEMENTATION */

 #  ifndef PNG_ARM_NEON_IMPLEMENTATION
      /* Use the intrinsics code by default. */
@@ -300,46 +300,9 @@

 /* SECURITY and SAFETY:
 *
- * By default libpng is built without any internal limits on image size,
- * individual heap (png_malloc) allocations or the total amount of memory used.
- * If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used
- * (unless individually overridden).  These limits are believed to be fairly
- * safe, but builders of secure systems should verify the values against the
- * real system capabilities.
- */
-#ifdef PNG_SAFE_LIMITS_SUPPORTED
-   /* 'safe' limits */
-#  ifndef PNG_USER_WIDTH_MAX
-#     define PNG_USER_WIDTH_MAX 1000000
-#  endif
-#  ifndef PNG_USER_HEIGHT_MAX
-#     define PNG_USER_HEIGHT_MAX 1000000
-#  endif
-#  ifndef PNG_USER_CHUNK_CACHE_MAX
-#     define PNG_USER_CHUNK_CACHE_MAX 128
-#  endif
-#  ifndef PNG_USER_CHUNK_MALLOC_MAX
-#     define PNG_USER_CHUNK_MALLOC_MAX 8000000
-#  endif
-#else
-   /* values for no limits */
-#  ifndef PNG_USER_WIDTH_MAX
-#     define PNG_USER_WIDTH_MAX 0x7fffffff
-#  endif
-#  ifndef PNG_USER_HEIGHT_MAX
-#     define PNG_USER_HEIGHT_MAX 0x7fffffff
-#  endif
-#  ifndef PNG_USER_CHUNK_CACHE_MAX
-#     define PNG_USER_CHUNK_CACHE_MAX 0
-#  endif
-#  ifndef PNG_USER_CHUNK_MALLOC_MAX
-#     define PNG_USER_CHUNK_MALLOC_MAX 0
-#  endif
-#endif
-
-/* Moved to pngpriv.h at libpng-1.5.0 */
-/* NOTE: some of these may have been used in external applications as
- * these definitions were exposed in pngconf.h prior to 1.5.
+ * libpng is built with support for internal limits on image dimensions and
+ * memory usage.  These are documented in scripts/pnglibconf.dfa of the
+ * source and recorded in the machine generated header file pnglibconf.h.
 */

 /* If you are running on a machine where you cannot allocate more
@@ -582,13 +545,13 @@
 #define PNG_RGB_TO_GRAY_WARN  0x400000
 #define PNG_RGB_TO_GRAY       0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
 #define PNG_ENCODE_ALPHA      0x800000 /* Added to libpng-1.5.4 */
-#define PNG_ADD_ALPHA         0x1000000 /* Added to libpng-1.2.7 */
-#define PNG_EXPAND_tRNS       0x2000000 /* Added to libpng-1.2.9 */
-#define PNG_SCALE_16_TO_8     0x4000000 /* Added to libpng-1.5.4 */
-                       /*   0x8000000 unused */
-                       /*  0x10000000 unused */
-                       /*  0x20000000 unused */
-                       /*  0x40000000 unused */
+#define PNG_ADD_ALPHA        0x1000000 /* Added to libpng-1.2.7 */
+#define PNG_EXPAND_tRNS      0x2000000 /* Added to libpng-1.2.9 */
+#define PNG_SCALE_16_TO_8    0x4000000 /* Added to libpng-1.5.4 */
+                       /*    0x8000000 unused */
+                       /*   0x10000000 unused */
+                       /*   0x20000000 unused */
+                       /*   0x40000000 unused */
 /* Flags for png_create_struct */
 #define PNG_STRUCT_PNG   0x0001
 #define PNG_STRUCT_INFO  0x0002
@@ -855,7 +818,7 @@ PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
   /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
    * encoded value with maximum error 0.646365.  Note that the input is not a
    * 16-bit value; it has been multiplied by 255! */
-#endif /* PNG_SIMPLIFIED_READ/WRITE */
+#endif /* SIMPLIFIED_READ/WRITE */


 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
@@ -910,7 +873,7 @@ PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
   defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
 /* Internal array allocator, outputs no error or warning messages on failure,
- * just returns NULL.  
+ * just returns NULL.
 */
 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
   int nelements, size_t element_size),PNG_ALLOCATED);
@@ -1229,7 +1192,7 @@ PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
   PNG_EMPTY);
   /* Finish a row while reading, dealing with interlacing passes, etc. */
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 /* Initialize the row buffers, etc. */
 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
@@ -1305,7 +1268,7 @@ PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
 #ifdef PNG_READ_iCCP_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif /* PNG_READ_iCCP_SUPPORTED */
+#endif /* READ_iCCP */

 #ifdef PNG_READ_iTXt_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
@@ -1340,7 +1303,7 @@ PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
 #ifdef PNG_READ_sPLT_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif /* PNG_READ_sPLT_SUPPORTED */
+#endif /* READ_sPLT */

 #ifdef PNG_READ_sRGB_SUPPORTED
 PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
@@ -1454,7 +1417,7 @@ PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
    png_inforp info_ptr),PNG_EMPTY);
 #  endif

-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+#endif /* PROGRESSIVE_READ */

 /* Added at libpng version 1.6.0 */
 #ifdef PNG_GAMMA_SUPPORTED
--- a/pngread.c
+++ b/pngread.c
@@ -1,8 +1,8 @@

 /* pngread.c - read a PNG file
 *
- * Last changed in libpng 1.6.15 [(PENDING RELEASE)]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2015 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.)
 *
@@ -44,7 +44,7 @@ png_create_read_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 {
   png_structp png_ptr = png_create_png_struct(user_png_ver, error_ptr,
      error_fn, warn_fn, mem_ptr, malloc_fn, free_fn);
-#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* USER_MEM */

   if (png_ptr != NULL)
   {
@@ -113,20 +113,20 @@ png_read_info(png_structrp png_ptr, png_inforp info_ptr)
       */
      if (chunk_name == png_IDAT)
      {
-         if (!(png_ptr->mode & PNG_HAVE_IHDR))
+         if ((png_ptr->mode & PNG_HAVE_IHDR) == 0)
            png_chunk_error(png_ptr, "Missing IHDR before IDAT");

         else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
-             !(png_ptr->mode & PNG_HAVE_PLTE))
+             (png_ptr->mode & PNG_HAVE_PLTE) == 0)
            png_chunk_error(png_ptr, "Missing PLTE before IDAT");

-         else if (png_ptr->mode & PNG_AFTER_IDAT)
+         else if ((png_ptr->mode & PNG_AFTER_IDAT) != 0)
            png_chunk_benign_error(png_ptr, "Too many IDATs found");

         png_ptr->mode |= PNG_HAVE_IDAT;
      }

-      else if (png_ptr->mode & PNG_HAVE_IDAT)
+      else if ((png_ptr->mode & PNG_HAVE_IDAT) != 0)
         png_ptr->mode |= PNG_AFTER_IDAT;

      /* This should be a binary subdivision search or a hash for
@@ -252,7 +252,7 @@ png_read_info(png_structrp png_ptr, png_inforp info_ptr)
            PNG_HANDLE_CHUNK_AS_DEFAULT);
   }
 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 /* Optional call to update the users info_ptr structure */
 void PNGAPI
@@ -302,7 +302,7 @@ png_start_read_image(png_structrp png_ptr)
            "png_start_read_image/png_read_update_info: duplicate call");
   }
 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 #ifdef PNG_MNG_FEATURES_SUPPORTED
@@ -315,7 +315,7 @@ png_do_read_intrapixel(png_row_infop row_info, png_bytep row)
   png_debug(1, "in png_do_read_intrapixel");

   if (
-       (row_info->color_type & PNG_COLOR_MASK_COLOR))
+       (row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
   {
      int bytes_per_pixel;
      png_uint_32 row_width = row_info->width;
@@ -369,7 +369,7 @@ png_do_read_intrapixel(png_row_infop row_info, png_bytep row)
      }
   }
 }
-#endif /* PNG_MNG_FEATURES_SUPPORTED */
+#endif /* MNG_FEATURES */

 void PNGAPI
 png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
@@ -385,7 +385,7 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
   /* png_read_start_row sets the information (in particular iwidth) for this
    * interlace pass.
    */
-   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+   if ((png_ptr->flags & PNG_FLAG_ROW_INIT) == 0)
      png_read_start_row(png_ptr);

   /* 1.5.6: row_info moved out of png_struct to a local here. */
@@ -401,42 +401,42 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
   {
   /* Check for transforms that have been set but were defined out */
 #if defined(PNG_WRITE_INVERT_SUPPORTED) && !defined(PNG_READ_INVERT_SUPPORTED)
-   if (png_ptr->transformations & PNG_INVERT_MONO)
+   if ((png_ptr->transformations & PNG_INVERT_MONO) != 0)
      png_warning(png_ptr, "PNG_READ_INVERT_SUPPORTED is not defined");
 #endif

 #if defined(PNG_WRITE_FILLER_SUPPORTED) && !defined(PNG_READ_FILLER_SUPPORTED)
-   if (png_ptr->transformations & PNG_FILLER)
+   if ((png_ptr->transformations & PNG_FILLER) != 0)
      png_warning(png_ptr, "PNG_READ_FILLER_SUPPORTED is not defined");
 #endif

 #if defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
    !defined(PNG_READ_PACKSWAP_SUPPORTED)
-   if (png_ptr->transformations & PNG_PACKSWAP)
+   if ((png_ptr->transformations & PNG_PACKSWAP) != 0)
      png_warning(png_ptr, "PNG_READ_PACKSWAP_SUPPORTED is not defined");
 #endif

 #if defined(PNG_WRITE_PACK_SUPPORTED) && !defined(PNG_READ_PACK_SUPPORTED)
-   if (png_ptr->transformations & PNG_PACK)
+   if ((png_ptr->transformations & PNG_PACK) != 0)
      png_warning(png_ptr, "PNG_READ_PACK_SUPPORTED is not defined");
 #endif

 #if defined(PNG_WRITE_SHIFT_SUPPORTED) && !defined(PNG_READ_SHIFT_SUPPORTED)
-   if (png_ptr->transformations & PNG_SHIFT)
+   if ((png_ptr->transformations & PNG_SHIFT) != 0)
      png_warning(png_ptr, "PNG_READ_SHIFT_SUPPORTED is not defined");
 #endif

 #if defined(PNG_WRITE_BGR_SUPPORTED) && !defined(PNG_READ_BGR_SUPPORTED)
-   if (png_ptr->transformations & PNG_BGR)
+   if ((png_ptr->transformations & PNG_BGR) != 0)
      png_warning(png_ptr, "PNG_READ_BGR_SUPPORTED is not defined");
 #endif

 #if defined(PNG_WRITE_SWAP_SUPPORTED) && !defined(PNG_READ_SWAP_SUPPORTED)
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
+   if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0)
      png_warning(png_ptr, "PNG_READ_SWAP_SUPPORTED is not defined");
 #endif
   }
-#endif /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */

 #ifdef PNG_READ_INTERLACING_SUPPORTED
   /* If interlaced and we do not need a new row, combine row and return.
@@ -445,7 +445,8 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
    * untransformed) and, because of the libpng API for interlaced images, this
    * means we must transform before de-interlacing.
    */
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   if (png_ptr->interlaced != 0 &&
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
   {
      switch (png_ptr->pass)
      {
@@ -516,7 +517,7 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)

         default:
         case 6:
-            if (!(png_ptr->row_number & 1))
+            if ((png_ptr->row_number & 1) == 0)
            {
               png_read_finish_row(png_ptr);
               return;
@@ -526,7 +527,7 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
   }
 #endif

-   if (!(png_ptr->mode & PNG_HAVE_IDAT))
+   if ((png_ptr->mode & PNG_HAVE_IDAT) == 0)
      png_error(png_ptr, "Invalid attempt to read row data");

   /* Fill the row with IDAT data: */
@@ -549,7 +550,7 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
   memcpy(png_ptr->prev_row, png_ptr->row_buf, row_info.rowbytes + 1);

 #ifdef PNG_MNG_FEATURES_SUPPORTED
-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
       (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
   {
      /* Intrapixel differencing */
@@ -575,8 +576,8 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)

 #ifdef PNG_READ_INTERLACING_SUPPORTED
   /* Expand interlaced rows to full size */
-   if (png_ptr->interlaced &&
-      (png_ptr->transformations & PNG_INTERLACE))
+   if (png_ptr->interlaced != 0 &&
+      (png_ptr->transformations & PNG_INTERLACE) != 0)
   {
      if (png_ptr->pass < 6)
         png_do_read_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass,
@@ -604,7 +605,7 @@ png_read_row(png_structrp png_ptr, png_bytep row, png_bytep dsp_row)
      (*(png_ptr->read_row_fn))(png_ptr, png_ptr->row_number, png_ptr->pass);

 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read one or more rows of image data.  If the image is interlaced,
@@ -671,7 +672,7 @@ png_read_rows(png_structrp png_ptr, png_bytepp row,
         dp++;
      }
 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read the entire image.  If the image has an alpha channel or a tRNS
@@ -699,7 +700,7 @@ png_read_image(png_structrp png_ptr, png_bytepp image)
      return;

 #ifdef PNG_READ_INTERLACING_SUPPORTED
-   if (!(png_ptr->flags & PNG_FLAG_ROW_INIT))
+   if ((png_ptr->flags & PNG_FLAG_ROW_INIT) == 0)
   {
      pass = png_set_interlace_handling(png_ptr);
      /* And make sure transforms are initialized. */
@@ -707,7 +708,8 @@ png_read_image(png_structrp png_ptr, png_bytepp image)
   }
   else
   {
-      if (png_ptr->interlaced && !(png_ptr->transformations & PNG_INTERLACE))
+      if (png_ptr->interlaced != 0 &&
+          (png_ptr->transformations & PNG_INTERLACE) == 0)
      {
         /* Caller called png_start_read_image or png_read_update_info without
          * first turning on the PNG_INTERLACE transform.  We can fix this here,
@@ -744,7 +746,7 @@ png_read_image(png_structrp png_ptr, png_bytepp image)
      }
   }
 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
 /* Read the end of the PNG file.  Will not read past the end of the
@@ -767,7 +769,7 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
    * still be pending IDAT data and an owned zstream.  Deal with this here.
    */
 #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
-   if (!png_chunk_unknown_handling(png_ptr, png_IDAT))
+   if (png_chunk_unknown_handling(png_ptr, png_IDAT) == 0)
 #endif
      png_read_finish_IDAT(png_ptr);

@@ -797,7 +799,8 @@ 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))
+            if ((length > 0) ||
+                (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);
@@ -811,7 +814,7 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
         /* Zero length IDATs are legal after the last IDAT has been
          * read, but not after other chunks have been read.
          */
-         if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT))
+         if ((length > 0) || (png_ptr->mode & PNG_HAVE_CHUNK_AFTER_IDAT) != 0)
            png_benign_error(png_ptr, "Too many IDATs found");

         png_crc_finish(png_ptr, length);
@@ -907,9 +910,9 @@ png_read_end(png_structrp png_ptr, png_inforp info_ptr)
      else
         png_handle_unknown(png_ptr, info_ptr, length,
            PNG_HANDLE_CHUNK_AS_DEFAULT);
-   } while (!(png_ptr->mode & PNG_HAVE_IEND));
+   } while ((png_ptr->mode & PNG_HAVE_IEND) == 0);
 }
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* SEQUENTIAL_READ */

 /* Free all memory used in the read struct */
 static void
@@ -935,7 +938,7 @@ png_read_destroy(png_structrp png_ptr)
   png_ptr->quantize_index = NULL;
 #endif

-   if (png_ptr->free_me & PNG_FREE_PLTE)
+   if ((png_ptr->free_me & PNG_FREE_PLTE) != 0)
   {
      png_zfree(png_ptr, png_ptr->palette);
      png_ptr->palette = NULL;
@@ -944,7 +947,7 @@ png_read_destroy(png_structrp png_ptr)

 #if defined(PNG_tRNS_SUPPORTED) || \
    defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-   if (png_ptr->free_me & PNG_FREE_TRNS)
+   if ((png_ptr->free_me & PNG_FREE_TRNS) != 0)
   {
      png_free(png_ptr, png_ptr->trans_alpha);
      png_ptr->trans_alpha = NULL;
@@ -1039,7 +1042,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,

   /* Tell libpng to strip 16-bit/color files down to 8 bits per color.
    */
-   if (transforms & PNG_TRANSFORM_SCALE_16)
+   if ((transforms & PNG_TRANSFORM_SCALE_16) != 0)
     /* Added at libpng-1.5.4. "strip_16" produces the same result that it
      * did in earlier versions, while "scale_16" is now more accurate.
      */
@@ -1053,7 +1056,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
    * latter by doing SCALE first.  This is ok and allows apps not to check for
    * which is supported to get the right answer.
    */
-   if (transforms & PNG_TRANSFORM_STRIP_16)
+   if ((transforms & PNG_TRANSFORM_STRIP_16) != 0)
 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
      png_set_strip_16(png_ptr);
 #else
@@ -1063,7 +1066,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
   /* Strip alpha bytes from the input data without combining with
    * the background (not recommended).
    */
-   if (transforms & PNG_TRANSFORM_STRIP_ALPHA)
+   if ((transforms & PNG_TRANSFORM_STRIP_ALPHA) != 0)
 #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED
      png_set_strip_alpha(png_ptr);
 #else
@@ -1073,7 +1076,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
   /* Extract multiple pixels with bit depths of 1, 2, or 4 from a single
    * byte into separate bytes (useful for paletted and grayscale images).
    */
-   if (transforms & PNG_TRANSFORM_PACKING)
+   if ((transforms & PNG_TRANSFORM_PACKING) != 0)
 #ifdef PNG_READ_PACK_SUPPORTED
      png_set_packing(png_ptr);
 #else
@@ -1083,7 +1086,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
   /* Change the order of packed pixels to least significant bit first
    * (not useful if you are using png_set_packing).
    */
-   if (transforms & PNG_TRANSFORM_PACKSWAP)
+   if ((transforms & PNG_TRANSFORM_PACKSWAP) != 0)
 #ifdef PNG_READ_PACKSWAP_SUPPORTED
      png_set_packswap(png_ptr);
 #else
@@ -1095,7 +1098,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
    * Expand paletted or RGB images with transparency to full alpha
    * channels so the data will be available as RGBA quartets.
    */
-   if (transforms & PNG_TRANSFORM_EXPAND)
+   if ((transforms & PNG_TRANSFORM_EXPAND) != 0)
 #ifdef PNG_READ_EXPAND_SUPPORTED
      png_set_expand(png_ptr);
 #else
@@ -1107,7 +1110,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,

   /* Invert monochrome files to have 0 as white and 1 as black
    */
-   if (transforms & PNG_TRANSFORM_INVERT_MONO)
+   if ((transforms & PNG_TRANSFORM_INVERT_MONO) != 0)
 #ifdef PNG_READ_INVERT_SUPPORTED
      png_set_invert_mono(png_ptr);
 #else
@@ -1118,16 +1121,16 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
    * [0,65535] to the original [0,7] or [0,31], or whatever range the
    * colors were originally in:
    */
-   if (transforms & PNG_TRANSFORM_SHIFT)
+   if ((transforms & PNG_TRANSFORM_SHIFT) != 0)
 #ifdef PNG_READ_SHIFT_SUPPORTED
-      if (info_ptr->valid & PNG_INFO_sBIT)
+      if ((info_ptr->valid & PNG_INFO_sBIT) != 0)
         png_set_shift(png_ptr, &info_ptr->sig_bit);
 #else
      png_app_error(png_ptr, "PNG_TRANSFORM_SHIFT not supported");
 #endif

   /* Flip the RGB pixels to BGR (or RGBA to BGRA) */
-   if (transforms & PNG_TRANSFORM_BGR)
+   if ((transforms & PNG_TRANSFORM_BGR) != 0)
 #ifdef PNG_READ_BGR_SUPPORTED
      png_set_bgr(png_ptr);
 #else
@@ -1135,7 +1138,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

   /* Swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
-   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+   if ((transforms & PNG_TRANSFORM_SWAP_ALPHA) != 0)
 #ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
      png_set_swap_alpha(png_ptr);
 #else
@@ -1143,7 +1146,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

   /* Swap bytes of 16-bit files to least significant byte first */
-   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+   if ((transforms & PNG_TRANSFORM_SWAP_ENDIAN) != 0)
 #ifdef PNG_READ_SWAP_SUPPORTED
      png_set_swap(png_ptr);
 #else
@@ -1152,7 +1155,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,

 /* Added at libpng-1.2.41 */
   /* Invert the alpha channel from opacity to transparency */
-   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+   if ((transforms & PNG_TRANSFORM_INVERT_ALPHA) != 0)
 #ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
      png_set_invert_alpha(png_ptr);
 #else
@@ -1161,7 +1164,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,

 /* Added at libpng-1.2.41 */
   /* Expand grayscale image to RGB */
-   if (transforms & PNG_TRANSFORM_GRAY_TO_RGB)
+   if ((transforms & PNG_TRANSFORM_GRAY_TO_RGB) != 0)
 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
      png_set_gray_to_rgb(png_ptr);
 #else
@@ -1169,7 +1172,7 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

 /* Added at libpng-1.5.4 */
-   if (transforms & PNG_TRANSFORM_EXPAND_16)
+   if ((transforms & PNG_TRANSFORM_EXPAND_16) != 0)
 #ifdef PNG_READ_EXPAND_16_SUPPORTED
      png_set_expand_16(png_ptr);
 #else
@@ -1217,8 +1220,8 @@ png_read_png(png_structrp png_ptr, png_inforp info_ptr,

   PNG_UNUSED(params)
 }
-#endif /* PNG_INFO_IMAGE_SUPPORTED */
-#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
+#endif /* INFO_IMAGE */
+#endif /* SEQUENTIAL_READ */

 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED
 /* SIMPLIFIED READ
@@ -1327,10 +1330,10 @@ png_image_format(png_structrp png_ptr)
 {
   png_uint_32 format = 0;

-   if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
+   if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
      format |= PNG_FORMAT_FLAG_COLOR;

-   if (png_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+   if ((png_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
      format |= PNG_FORMAT_FLAG_ALPHA;

   /* Use png_ptr here, not info_ptr, because by examination png_handle_tRNS
@@ -1344,7 +1347,7 @@ png_image_format(png_structrp png_ptr)
   if (png_ptr->bit_depth == 16)
      format |= PNG_FORMAT_FLAG_LINEAR;

-   if (png_ptr->color_type & PNG_COLOR_MASK_PALETTE)
+   if ((png_ptr->color_type & PNG_COLOR_MASK_PALETTE) != 0)
      format |= PNG_FORMAT_FLAG_COLORMAP;

   return format;
@@ -1444,7 +1447,7 @@ png_image_begin_read_from_stdio(png_imagep image, FILE* file)
   {
      if (file != NULL)
      {
-         if (png_image_read_init(image))
+         if (png_image_read_init(image) != 0)
         {
            /* This is slightly evil, but png_init_io doesn't do anything other
             * than this and we haven't changed the standard IO functions so
@@ -1478,7 +1481,7 @@ png_image_begin_read_from_file(png_imagep image, const char *file_name)

         if (fp != NULL)
         {
-            if (png_image_read_init(image))
+            if (png_image_read_init(image) != 0)
            {
               image->opaque->png_ptr->io_ptr = fp;
               image->opaque->owned_file = 1;
@@ -1504,7 +1507,7 @@ png_image_begin_read_from_file(png_imagep image, const char *file_name)

   return 0;
 }
-#endif /* PNG_STDIO_SUPPORTED */
+#endif /* STDIO */

 static void PNGCBAPI
 png_image_memory_read(png_structp png_ptr, png_bytep out, png_size_t need)
@@ -1543,7 +1546,7 @@ int PNGAPI png_image_begin_read_from_memory(png_imagep image,
   {
      if (memory != NULL && size > 0)
      {
-         if (png_image_read_init(image))
+         if (png_image_read_init(image) != 0)
         {
            /* Now set the IO functions to read from the memory buffer and
             * store it into io_ptr.  Again do this in-place to avoid calling a
@@ -1615,14 +1618,14 @@ 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, (sizeof chunks_to_process)/5);
+         chunks_to_process, (int)/*SAFE*/(sizeof chunks_to_process)/5);
    }
 }

 #  define PNG_SKIP_CHUNKS(p) png_image_skip_unused_chunks(p)
 #else
 #  define PNG_SKIP_CHUNKS(p) ((void)0)
-#endif /* PNG_HANDLE_AS_UNKNOWN_SUPPORTED */
+#endif /* HANDLE_AS_UNKNOWN */

 /* The following macro gives the exact rounded answer for all values in the
 * range 0..255 (it actually divides by 51.2, but the rounding still generates
@@ -1635,9 +1638,9 @@ static void
 set_file_encoding(png_image_read_control *display)
 {
   png_fixed_point g = display->image->opaque->png_ptr->colorspace.gamma;
-   if (png_gamma_significant(g))
+   if (png_gamma_significant(g) != 0)
   {
-      if (png_gamma_not_sRGB(g))
+      if (png_gamma_not_sRGB(g) != 0)
      {
         display->file_encoding = P_FILE;
         display->gamma_to_linear = png_reciprocal(g);
@@ -1732,7 +1735,7 @@ png_create_colormap_entry(png_image_read_control *display,
   png_uint_32 alpha, int encoding)
 {
   png_imagep image = display->image;
-   const int output_encoding = (image->format & PNG_FORMAT_FLAG_LINEAR) ?
+   const int output_encoding = (image->format & PNG_FORMAT_FLAG_LINEAR) != 0 ?
      P_LINEAR : P_sRGB;
   const int convert_to_Y = (image->format & PNG_FORMAT_FLAG_COLOR) == 0 &&
      (red != green || green != blue);
@@ -1762,7 +1765,7 @@ png_create_colormap_entry(png_image_read_control *display,
      green = png_gamma_16bit_correct(green*257, g);
      blue = png_gamma_16bit_correct(blue*257, g);

-      if (convert_to_Y || output_encoding == P_LINEAR)
+      if (convert_to_Y != 0 || output_encoding == P_LINEAR)
      {
         alpha *= 257;
         encoding = P_LINEAR;
@@ -1789,7 +1792,8 @@ png_create_colormap_entry(png_image_read_control *display,
      encoding = P_LINEAR;
   }

-   else if (encoding == P_sRGB && (convert_to_Y || output_encoding == P_LINEAR))
+   else if (encoding == P_sRGB &&
+       (convert_to_Y  != 0 || output_encoding == P_LINEAR))
   {
      /* The values are 8-bit sRGB values, but must be converted to 16-bit
       * linear.
@@ -1847,7 +1851,7 @@ png_create_colormap_entry(png_image_read_control *display,
 #        define afirst 0
 #     endif
 #     ifdef PNG_FORMAT_BGR_SUPPORTED
-         const int bgr = (image->format & PNG_FORMAT_FLAG_BGR) ? 2 : 0;
+         const int bgr = (image->format & PNG_FORMAT_FLAG_BGR) != 0 ? 2 : 0;
 #     else
 #        define bgr 0
 #     endif
@@ -2059,7 +2063,7 @@ png_image_read_colormap(png_voidp argument)

   const png_structrp png_ptr = image->opaque->png_ptr;
   const png_uint_32 output_format = image->format;
-   const int output_encoding = (output_format & PNG_FORMAT_FLAG_LINEAR) ?
+   const int output_encoding = (output_format & PNG_FORMAT_FLAG_LINEAR) != 0 ?
      P_LINEAR : P_sRGB;

   unsigned int cmap_entries;
@@ -2098,7 +2102,7 @@ png_image_read_colormap(png_voidp argument)
      else
      {
         back_g = display->background->green;
-         if (output_format & PNG_FORMAT_FLAG_COLOR)
+         if ((output_format & PNG_FORMAT_FLAG_COLOR) != 0)
         {
            back_r = display->background->red;
            back_b = display->background->blue;
@@ -2240,7 +2244,7 @@ png_image_read_colormap(png_voidp argument)
            {
               unsigned int back_alpha;

-               if (output_format & PNG_FORMAT_FLAG_ALPHA)
+               if ((output_format & PNG_FORMAT_FLAG_ALPHA) != 0)
                  back_alpha = 0;

               else
@@ -2281,8 +2285,14 @@ png_image_read_colormap(png_voidp argument)
                     output_processing = PNG_CMAP_NONE;
                     break;
                  }
-
+#ifdef __COVERITY__
+                 /* Coverity claims that output_encoding cannot be 2 (P_LINEAR)
+                  * here.
+                  */
+                  back_alpha = 255;
+#else
                  back_alpha = output_encoding == P_LINEAR ? 65535 : 255;
+#endif
               }

               /* output_processing means that the libpng-processed row will be
@@ -2321,7 +2331,7 @@ png_image_read_colormap(png_voidp argument)
          */
         data_encoding = P_sRGB;

-         if (output_format & PNG_FORMAT_FLAG_ALPHA)
+         if ((output_format & PNG_FORMAT_FLAG_ALPHA) != 0)
         {
            if (PNG_GA_COLORMAP_ENTRIES > image->colormap_entries)
               png_error(png_ptr, "gray+alpha color-map: too few entries");
@@ -2407,7 +2417,14 @@ png_image_read_colormap(png_voidp argument)
                */
               background_index = i;
               png_create_colormap_entry(display, i++, back_r, back_g, back_b,
-                  output_encoding == P_LINEAR ? 65535U : 255U, output_encoding);
+#ifdef __COVERITY__
+                 /* Coverity claims that output_encoding cannot be 2 (P_LINEAR)
+                  * here.
+                  */ 255U,
+#else
+                  output_encoding == P_LINEAR ? 65535U : 255U,
+#endif
+                  output_encoding);

               /* For non-opaque input composite on the sRGB background - this
                * requires inverting the encoding for each component.  The input
@@ -2516,7 +2533,7 @@ png_image_read_colormap(png_voidp argument)
                */
               if ((png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA ||
                  png_ptr->num_trans > 0) &&
-                  png_gamma_not_sRGB(png_ptr->colorspace.gamma))
+                  png_gamma_not_sRGB(png_ptr->colorspace.gamma) != 0)
               {
                  cmap_entries = make_gray_file_colormap(display);
                  data_encoding = P_FILE;
@@ -2604,7 +2621,7 @@ png_image_read_colormap(png_voidp argument)
               /* Is there alpha in the output too?  If so all four channels are
                * processed into a special RGB cube with alpha support.
                */
-               if (output_format & PNG_FORMAT_FLAG_ALPHA)
+               if ((output_format & PNG_FORMAT_FLAG_ALPHA) != 0)
               {
                  png_uint_32 r;

@@ -2778,7 +2795,7 @@ png_image_read_colormap(png_voidp argument)

            for (i=0; i < cmap_entries; ++i)
            {
-               if (do_background && i < num_trans && trans[i] < 255)
+               if (do_background != 0 && i < num_trans && trans[i] < 255)
               {
                  if (trans[i] == 0)
                     png_create_colormap_entry(display, i, back_r, back_g,
@@ -2823,8 +2840,8 @@ png_image_read_colormap(png_voidp argument)
   }

   /* Now deal with the output processing */
-   if (expand_tRNS && png_ptr->num_trans > 0 &&
-      (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) == 0)
+   if (expand_tRNS != 0 && png_ptr->num_trans > 0 &&
+       (png_ptr->color_type & PNG_COLOR_MASK_ALPHA) == 0)
      png_set_tRNS_to_alpha(png_ptr);

   switch (data_encoding)
@@ -3240,7 +3257,8 @@ png_image_read_composite(png_voidp argument)
      png_uint_32  height = image->height;
      png_uint_32  width = image->width;
      ptrdiff_t    step_row = display->row_bytes;
-      unsigned int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
+      unsigned int channels =
+          (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? 3 : 1;
      int pass;

      for (pass = 0; pass < passes; ++pass)
@@ -3538,7 +3556,8 @@ png_image_read_background(png_voidp argument)
            int swap_alpha = 0;

 #           ifdef PNG_SIMPLIFIED_READ_AFIRST_SUPPORTED
-               if (preserve_alpha && (image->format & PNG_FORMAT_FLAG_AFIRST))
+               if (preserve_alpha != 0 &&
+                   (image->format & PNG_FORMAT_FLAG_AFIRST) != 0)
                  swap_alpha = 1;
 #           endif

@@ -3647,10 +3666,10 @@ png_image_read_direct(png_voidp argument)
      int mode; /* alpha mode */

      /* Do this first so that we have a record if rgb to gray is happening. */
-      if (change & PNG_FORMAT_FLAG_COLOR)
+      if ((change & PNG_FORMAT_FLAG_COLOR) != 0)
      {
         /* gray<->color transformation required. */
-         if (format & PNG_FORMAT_FLAG_COLOR)
+         if ((format & PNG_FORMAT_FLAG_COLOR) != 0)
            png_set_gray_to_rgb(png_ptr);

         else
@@ -3668,7 +3687,7 @@ png_image_read_direct(png_voidp argument)
             * enormous change) 'do_local_background' is used to indicate that
             * the problem exists.
             */
-            if (base_format & PNG_FORMAT_FLAG_ALPHA)
+            if ((base_format & PNG_FORMAT_FLAG_ALPHA) != 0)
               do_local_background = 1/*maybe*/;

            png_set_rgb_to_gray_fixed(png_ptr, PNG_ERROR_ACTION_NONE,
@@ -3683,8 +3702,8 @@ png_image_read_direct(png_voidp argument)
      {
         png_fixed_point input_gamma_default;

-         if ((base_format & PNG_FORMAT_FLAG_LINEAR) &&
-            (image->flags & PNG_IMAGE_FLAG_16BIT_sRGB) == 0)
+         if ((base_format & PNG_FORMAT_FLAG_LINEAR) != 0 &&
+             (image->flags & PNG_IMAGE_FLAG_16BIT_sRGB) == 0)
            input_gamma_default = PNG_GAMMA_LINEAR;
         else
            input_gamma_default = PNG_DEFAULT_sRGB;
@@ -3700,7 +3719,7 @@ png_image_read_direct(png_voidp argument)
         /* If there *is* an alpha channel in the input it must be multiplied
          * out; use PNG_ALPHA_STANDARD, otherwise just use PNG_ALPHA_PNG.
          */
-         if (base_format & PNG_FORMAT_FLAG_ALPHA)
+         if ((base_format & PNG_FORMAT_FLAG_ALPHA) != 0)
            mode = PNG_ALPHA_STANDARD; /* associated alpha */

         else
@@ -3731,7 +3750,7 @@ png_image_read_direct(png_voidp argument)
          * final value.
          */
         if (png_muldiv(&gtest, output_gamma, png_ptr->colorspace.gamma,
-               PNG_FP_1) && !png_gamma_significant(gtest))
+               PNG_FP_1) != 0 && png_gamma_significant(gtest) == 0)
            do_local_background = 0;

         else if (mode == PNG_ALPHA_STANDARD)
@@ -3744,9 +3763,9 @@ png_image_read_direct(png_voidp argument)
      }

      /* If the bit-depth changes then handle that here. */
-      if (change & PNG_FORMAT_FLAG_LINEAR)
+      if ((change & PNG_FORMAT_FLAG_LINEAR) != 0)
      {
-         if (linear /*16-bit output*/)
+         if (linear != 0 /*16-bit output*/)
            png_set_expand_16(png_ptr);

         else /* 8-bit output */
@@ -3756,13 +3775,13 @@ png_image_read_direct(png_voidp argument)
      }

      /* Now the background/alpha channel changes. */
-      if (change & PNG_FORMAT_FLAG_ALPHA)
+      if ((change & PNG_FORMAT_FLAG_ALPHA) != 0)
      {
         /* Removing an alpha channel requires composition for the 8-bit
          * formats; for the 16-bit it is already done, above, by the
          * pre-multiplication and the channel just needs to be stripped.
          */
-         if (base_format & PNG_FORMAT_FLAG_ALPHA)
+         if ((base_format & PNG_FORMAT_FLAG_ALPHA) != 0)
         {
            /* If RGB->gray is happening the alpha channel must be left and the
             * operation completed locally.
@@ -3827,7 +3846,7 @@ png_image_read_direct(png_voidp argument)
               filler = 255;

 #           ifdef PNG_FORMAT_AFIRST_SUPPORTED
-               if (format & PNG_FORMAT_FLAG_AFIRST)
+               if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
               {
                  where = PNG_FILLER_BEFORE;
                  change &= ~PNG_FORMAT_FLAG_AFIRST;
@@ -3851,12 +3870,12 @@ png_image_read_direct(png_voidp argument)
      png_set_alpha_mode_fixed(png_ptr, mode, output_gamma);

 #     ifdef PNG_FORMAT_BGR_SUPPORTED
-         if (change & PNG_FORMAT_FLAG_BGR)
+         if ((change & PNG_FORMAT_FLAG_BGR) != 0)
         {
            /* Check only the output format; PNG is never BGR; don't do this if
             * the output is gray, but fix up the 'format' value in that case.
             */
-            if (format & PNG_FORMAT_FLAG_COLOR)
+            if ((format & PNG_FORMAT_FLAG_COLOR) != 0)
               png_set_bgr(png_ptr);

            else
@@ -3867,14 +3886,14 @@ png_image_read_direct(png_voidp argument)
 #     endif

 #     ifdef PNG_FORMAT_AFIRST_SUPPORTED
-         if (change & PNG_FORMAT_FLAG_AFIRST)
+         if ((change & PNG_FORMAT_FLAG_AFIRST) != 0)
         {
            /* Only relevant if there is an alpha channel - it's particularly
             * important to handle this correctly because do_local_compose may
             * be set above and then libpng will keep the alpha channel for this
             * code to remove.
             */
-            if (format & PNG_FORMAT_FLAG_ALPHA)
+            if ((format & PNG_FORMAT_FLAG_ALPHA) != 0)
            {
               /* Disable this if doing a local background,
                * TODO: remove this when local background is no longer required.
@@ -3897,7 +3916,7 @@ png_image_read_direct(png_voidp argument)
      {
         PNG_CONST png_uint_16 le = 0x0001;

-         if (*(png_const_bytep)&le)
+         if ((*(png_const_bytep) & le) != 0)
            png_set_swap(png_ptr);
      }

@@ -3922,10 +3941,10 @@ png_image_read_direct(png_voidp argument)
   {
      png_uint_32 info_format = 0;

-      if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
         info_format |= PNG_FORMAT_FLAG_COLOR;

-      if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+      if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
      {
         /* do_local_compose removes this channel below. */
         if (do_local_compose == 0)
@@ -3944,14 +3963,14 @@ png_image_read_direct(png_voidp argument)
         info_format |= PNG_FORMAT_FLAG_LINEAR;

 #     ifdef PNG_FORMAT_BGR_SUPPORTED
-         if (png_ptr->transformations & PNG_BGR)
+         if ((png_ptr->transformations & PNG_BGR) != 0)
            info_format |= PNG_FORMAT_FLAG_BGR;
 #     endif

 #     ifdef PNG_FORMAT_AFIRST_SUPPORTED
         if (do_local_background == 2)
         {
-            if (format & PNG_FORMAT_FLAG_AFIRST)
+            if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
               info_format |= PNG_FORMAT_FLAG_AFIRST;
         }

@@ -4080,7 +4099,7 @@ png_image_finish_read(png_imagep image, png_const_colorp background,
            /* Choose the correct 'end' routine; for the color-map case all the
             * setup has already been done.
             */
-            if (image->format & PNG_FORMAT_FLAG_COLORMAP)
+            if ((image->format & PNG_FORMAT_FLAG_COLORMAP) != 0)
               result =
                  png_safe_execute(image, png_image_read_colormap, &display) &&
                  png_safe_execute(image, png_image_read_colormapped, &display);
@@ -4110,5 +4129,5 @@ png_image_finish_read(png_imagep image, png_const_colorp background,
   return 0;
 }

-#endif /* PNG_SIMPLIFIED_READ_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED */
+#endif /* SIMPLIFIED_READ */
+#endif /* READ */
--- a/pngrio.c
+++ b/pngrio.c
@@ -1,8 +1,8 @@

 /* pngrio.c - functions for data input
 *
- * Last changed in libpng 1.6.9 [February 6, 2014]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2015 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.)
 *
@@ -117,4 +117,4 @@ png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
   png_ptr->output_flush_fn = NULL;
 #endif
 }
-#endif /* PNG_READ_SUPPORTED */
+#endif /* READ */
--- a/pngrtran.c
+++ b/pngrtran.c
--- a/pngrutil.c
+++ b/pngrutil.c
--- a/pngset.c
+++ b/pngset.c
@@ -1,8 +1,8 @@

 /* pngset.c - storage of image information into info struct
 *
- * Last changed in libpng 1.6.11 [June 5, 2014]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2015 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.)
 *
@@ -59,7 +59,7 @@ png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
   xy.whitey = white_y;

   if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy,
-      2/* override with app values*/))
+       2/* override with app values*/) != 0)
      info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;

   png_colorspace_sync_info(png_ptr, info_ptr);
@@ -90,7 +90,8 @@ png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr,
   XYZ.blue_Y = int_blue_Y;
   XYZ.blue_Z = int_blue_Z;

-   if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace, &XYZ, 2))
+   if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace,
+       &XYZ, 2) != 0)
      info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM;

   png_colorspace_sync_info(png_ptr, info_ptr);
@@ -129,9 +130,9 @@ png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X,
      png_fixed(png_ptr, blue_Y, "cHRM Red Y"),
      png_fixed(png_ptr, blue_Z, "cHRM Red Z"));
 }
-#  endif /* PNG_FLOATING_POINT_SUPPORTED */
+#  endif /* FLOATING_POINT */

-#endif /* PNG_cHRM_SUPPORTED */
+#endif /* cHRM */

 #ifdef PNG_gAMA_SUPPORTED
 void PNGFAPI
@@ -189,6 +190,7 @@ png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr,
   if (info_ptr->hist == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for hIST chunk data");
+
      return;
   }

@@ -227,13 +229,13 @@ png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr,
   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
      info_ptr->channels = 1;

-   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+   else if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0)
      info_ptr->channels = 3;

   else
      info_ptr->channels = 1;

-   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+   if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0)
      info_ptr->channels++;

   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
@@ -270,7 +272,7 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
   png_debug1(1, "in %s storage function", "pCAL");

   if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL
-      || (nparams > 0 && params == NULL))
+       || (nparams > 0 && params == NULL))
      return;

   length = strlen(purpose) + 1;
@@ -288,16 +290,19 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,

   /* Validate params[nparams] */
   for (i=0; i<nparams; ++i)
+   {
      if (params[i] == NULL ||
-         !png_check_fp_string(params[i], strlen(params[i])))
+          !png_check_fp_string(params[i], strlen(params[i])))
         png_error(png_ptr, "Invalid format for pCAL parameter");
+   }

   info_ptr->pcal_purpose = png_voidcast(png_charp,
-      png_malloc_warn(png_ptr, length));
+       png_malloc_warn(png_ptr, length));

   if (info_ptr->pcal_purpose == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL purpose");
+
      return;
   }

@@ -319,6 +324,7 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
   if (info_ptr->pcal_units == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL units");
+
      return;
   }

@@ -330,6 +336,7 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
   if (info_ptr->pcal_params == NULL)
   {
      png_warning(png_ptr, "Insufficient memory for pCAL params");
+
      return;
   }

@@ -346,6 +353,7 @@ png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr,
      if (info_ptr->pcal_params[i] == NULL)
      {
         png_warning(png_ptr, "Insufficient memory for pCAL parameter");
+
         return;
      }

@@ -395,6 +403,7 @@ png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
   if (info_ptr->scal_s_width == NULL)
   {
      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
+
      return;
   }

@@ -413,6 +422,7 @@ png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr,
      info_ptr->scal_s_width = NULL;

      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
+
      return;
   }

@@ -516,6 +526,7 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
      else
      {
         png_warning(png_ptr, "Invalid palette length");
+
         return;
      }
   }
@@ -528,7 +539,6 @@ png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr,
      ))
   {
      png_error(png_ptr, "Invalid palette");
-      return;
   }

   /* It may not actually be necessary to set png_ptr->palette here;
@@ -594,7 +604,8 @@ png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr,
   if (png_ptr == NULL || info_ptr == NULL)
      return;

-   if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent))
+   if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace,
+       srgb_intent) != 0)
   {
      /* This causes the gAMA and cHRM to be written too */
      info_ptr->colorspace.flags |=
@@ -651,6 +662,7 @@ png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
   if (new_iccp_name == NULL)
   {
      png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk");
+
      return;
   }

@@ -664,6 +676,7 @@ png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr,
      new_iccp_name = NULL;
      png_benign_error(png_ptr,
          "Insufficient memory to process iCCP profile");
+
      return;
   }

@@ -739,6 +752,7 @@ png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
      {
         png_chunk_report(png_ptr, "too many text chunks",
            PNG_CHUNK_WRITE_ERROR);
+
         return 1;
      }

@@ -794,7 +808,7 @@ png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
         else
            lang_key_len = 0;
      }
-#  else /* PNG_iTXt_SUPPORTED */
+#  else /* iTXt */
      {
         png_chunk_report(png_ptr, "iTXt chunk not supported",
            PNG_CHUNK_WRITE_ERROR);
@@ -827,6 +841,7 @@ png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr,
      {
         png_chunk_report(png_ptr, "text chunk: out of memory",
               PNG_CHUNK_WRITE_ERROR);
+
         return 1;
      }

@@ -891,7 +906,7 @@ png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
   png_debug1(1, "in %s storage function", "tIME");

   if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL ||
-       (png_ptr->mode & PNG_WROTE_tIME))
+       (png_ptr->mode & PNG_WROTE_tIME) != 0)
      return;

   if (mod_time->month == 0   || mod_time->month > 12  ||
@@ -900,6 +915,7 @@ png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr,
       mod_time->second > 60)
   {
      png_warning(png_ptr, "Ignoring invalid time value");
+
      return;
   }

@@ -916,6 +932,7 @@ png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,
   png_debug1(1, "in %s storage function", "tRNS");

   if (png_ptr == NULL || info_ptr == NULL)
+
      return;

   if (trans_alpha != NULL)
@@ -941,16 +958,21 @@ png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr,

   if (trans_color != NULL)
   {
-      int sample_max = (1 << info_ptr->bit_depth);
+#ifdef PNG_WARNINGS_SUPPORTED
+      if (info_ptr->bit_depth < 16)
+      {
+         int sample_max = (1 << info_ptr->bit_depth) - 1;

-      if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
-          trans_color->gray > sample_max) ||
-          (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
-          (trans_color->red > sample_max ||
-          trans_color->green > sample_max ||
-          trans_color->blue > sample_max)))
-         png_warning(png_ptr,
-            "tRNS chunk has out-of-range samples for bit_depth");
+         if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
+             trans_color->gray > sample_max) ||
+             (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
+             (trans_color->red > sample_max ||
+             trans_color->green > sample_max ||
+             trans_color->blue > sample_max)))
+            png_warning(png_ptr,
+               "tRNS chunk has out-of-range samples for bit_depth");
+      }
+#endif

      info_ptr->trans_color = *trans_color;

@@ -997,6 +1019,7 @@ png_set_sPLT(png_const_structrp png_ptr,
   {
      /* Out of memory or too many chunks */
      png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR);
+
      return;
   }

@@ -1065,7 +1088,7 @@ png_set_sPLT(png_const_structrp png_ptr,
   if (nentries > 0)
      png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR);
 }
-#endif /* PNG_sPLT_SUPPORTED */
+#endif /* sPLT */

 #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED
 static png_byte
@@ -1077,7 +1100,7 @@ check_location(png_const_structrp png_ptr, int location)
    * change; previously the app had to use the
    * png_set_unknown_chunk_location API below for each chunk.
    */
-   if (location == 0 && !(png_ptr->mode & PNG_IS_READ_STRUCT))
+   if (location == 0 && (png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
   {
      /* Write struct, so unknown chunks come from the app */
      png_app_warning(png_ptr,
@@ -1112,7 +1135,7 @@ png_set_unknown_chunks(png_const_structrp png_ptr,
   png_unknown_chunkp np;

   if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 ||
-      unknowns == NULL)
+       unknowns == NULL)
      return;

   /* Check for the failure cases where support has been disabled at compile
@@ -1123,17 +1146,19 @@ png_set_unknown_chunks(png_const_structrp png_ptr,
    */
 #  if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \
      defined(PNG_READ_SUPPORTED)
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
      {
         png_app_error(png_ptr, "no unknown chunk support on read");
+
         return;
      }
 #  endif
 #  if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \
      defined(PNG_WRITE_SUPPORTED)
-      if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
      {
         png_app_error(png_ptr, "no unknown chunk support on write");
+
         return;
      }
 #  endif
@@ -1151,6 +1176,7 @@ png_set_unknown_chunks(png_const_structrp png_ptr,
   {
      png_chunk_report(png_ptr, "too many unknown chunks",
         PNG_CHUNK_WRITE_ERROR);
+
      return;
   }

@@ -1217,7 +1243,7 @@ png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr,
      {
         png_app_error(png_ptr, "invalid unknown chunk location");
         /* Fake out the pre 1.6.0 behavior: */
-         if ((location & PNG_HAVE_IDAT)) /* undocumented! */
+         if ((location & PNG_HAVE_IDAT) != 0) /* undocumented! */
            location = PNG_AFTER_IDAT;

         else
@@ -1255,10 +1281,14 @@ add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep)
   /* Utility function: update the 'keep' state of a chunk if it is already in
    * the list, otherwise add it to the list.
    */
-   for (i=0; i<count; ++i, list += 5) if (memcmp(list, add, 4) == 0)
+   for (i=0; i<count; ++i, list += 5)
   {
-      list[4] = (png_byte)keep;
-      return count;
+      if (memcmp(list, add, 4) == 0)
+      {
+         list[4] = (png_byte)keep;
+
+         return count;
+      }
   }

   if (keep != PNG_HANDLE_CHUNK_AS_DEFAULT)
@@ -1284,6 +1314,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
   if (keep < 0 || keep >= PNG_HANDLE_CHUNK_LAST)
   {
      png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep");
+
      return;
   }

@@ -1322,7 +1353,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
      };

      chunk_list = chunks_to_ignore;
-      num_chunks = (sizeof chunks_to_ignore)/5;
+      num_chunks = (unsigned int)/*SAFE*/(sizeof chunks_to_ignore)/5U;
   }

   else /* num_chunks_in > 0 */
@@ -1333,6 +1364,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
          * which can be switched off.
          */
         png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list");
+
         return;
      }

@@ -1348,6 +1380,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
   if (num_chunks + old_num_chunks > UINT_MAX/5)
   {
      png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks");
+
      return;
   }

@@ -1382,12 +1415,15 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
      unsigned int i;

      for (i=0; i<num_chunks; ++i)
+      {
         old_num_chunks = add_one_chunk(new_list, old_num_chunks,
            chunk_list+5*i, keep);
+      }

      /* Now remove any spurious 'default' entries. */
      num_chunks = 0;
      for (i=0, inlist=outlist=new_list; i<old_num_chunks; ++i, inlist += 5)
+      {
         if (inlist[4])
         {
            if (outlist != inlist)
@@ -1395,6 +1431,7 @@ png_set_keep_unknown_chunks(png_structrp png_ptr, int keep,
            outlist += 5;
            ++num_chunks;
         }
+      }

      /* This means the application has removed all the specialized handling. */
      if (num_chunks == 0)
@@ -1446,7 +1483,8 @@ png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr,
   if (png_ptr == NULL || info_ptr == NULL)
      return;

-   if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+   if (info_ptr->row_pointers != NULL &&
+       (info_ptr->row_pointers != row_pointers))
      png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);

   info_ptr->row_pointers = row_pointers;
@@ -1466,7 +1504,7 @@ png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
       png_error(png_ptr, "invalid compression buffer size");

 #  ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-      if (png_ptr->mode & PNG_IS_READ_STRUCT)
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
      {
         png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */
         return;
@@ -1474,29 +1512,33 @@ png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
 #  endif

 #  ifdef PNG_WRITE_SUPPORTED
-      if (!(png_ptr->mode & PNG_IS_READ_STRUCT))
+      if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0)
      {
         if (png_ptr->zowner != 0)
         {
            png_warning(png_ptr,
              "Compression buffer size cannot be changed because it is in use");
+
            return;
         }

+#ifndef __COVERITY__
         if (size > ZLIB_IO_MAX)
         {
            png_warning(png_ptr,
               "Compression buffer size limited to system maximum");
            size = ZLIB_IO_MAX; /* must fit */
         }
+#endif

-         else if (size < 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;
         }

@@ -1512,7 +1554,7 @@ png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size)
 void PNGAPI
 png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask)
 {
-   if (png_ptr && info_ptr)
+   if (png_ptr != NULL && info_ptr != NULL)
      info_ptr->valid &= ~mask;
 }

@@ -1538,8 +1580,8 @@ png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max,
 void PNGAPI
 png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max)
 {
-    if (png_ptr != NULL)
-       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
+   if (png_ptr != NULL)
+      png_ptr->user_chunk_cache_max = user_chunk_cache_max;
 }

 /* This function was added to libpng 1.4.1 */
@@ -1550,7 +1592,7 @@ png_set_chunk_malloc_max (png_structrp png_ptr,
   if (png_ptr != NULL)
      png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
 }
-#endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
+#endif /* ?SET_USER_LIMITS */


 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
@@ -1573,7 +1615,7 @@ png_set_benign_errors(png_structrp png_ptr, int allowed)
      png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN |
         PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN);
 }
-#endif /* PNG_BENIGN_ERRORS_SUPPORTED */
+#endif /* BENIGN_ERRORS */

 #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED
   /* Whether to report invalid palette index; added at libng-1.5.10.
@@ -1596,4 +1638,4 @@ png_set_check_for_invalid_index(png_structrp png_ptr, int allowed)
      png_ptr->num_palette_max = -1;
 }
 #endif
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* READ || WRITE */
--- a/pngstruct.h
+++ b/pngstruct.h
@@ -101,7 +101,7 @@ typedef struct png_XYZ
 #endif /* COLORSPACE */

 #if defined(PNG_COLORSPACE_SUPPORTED) || defined(PNG_GAMMA_SUPPORTED)
-/* A colorspace is all the above plus, potentially, profile information,
+/* A colorspace is all the above plus, potentially, profile information;
 * however at present libpng does not use the profile internally so it is only
 * stored in the png_info struct (if iCCP is supported.)  The rendering intent
 * is retained here and is checked.
@@ -274,7 +274,7 @@ struct png_struct_def
 #ifdef PNG_READ_GAMMA_SUPPORTED
   png_color_16 background_1; /* background normalized to gamma 1.0 */
 #endif
-#endif /* PNG_bKGD_SUPPORTED */
+#endif /* bKGD */

 #ifdef PNG_WRITE_FLUSH_SUPPORTED
   png_flush_ptr output_flush_fn; /* Function for flushing output */
@@ -331,7 +331,7 @@ struct png_struct_def
   int process_mode;                 /* what push library is currently doing */
   int cur_palette;                  /* current push library palette index */

-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
+#endif /* PROGRESSIVE_READ */

 #if defined(__TURBOC__) && !defined(_Windows) && !defined(__FLAT__)
 /* For the Borland special 64K segment handler */
--- a/pngtest.c
+++ b/pngtest.c
@@ -1,8 +1,8 @@

 /* pngtest.c - a simple test program to test libpng
 *
- * Last changed in libpng 1.6.15 [(PENDING RELEASE)]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2015 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.)
 *
@@ -283,7 +283,8 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
       png_uint_32 n, nstop;
       int channel;
       int color_channels = row_info->channels;
-       if (row_info->color_type > 3)color_channels--;
+       if (row_info->color_type > 3)
+          color_channels--;

       for (n = 0, nstop=row_info->width; n<nstop; n++)
       {
@@ -310,7 +311,7 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
       }
    }
 }
-#endif /* PNG_WRITE_USER_TRANSFORM_SUPPORTED */
+#endif /* WRITE_USER_TRANSFORM */

 #ifndef PNG_STDIO_SUPPORTED
 /* START of code to validate stdio-free compilation */
@@ -419,7 +420,7 @@ pngtest_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
   pngtest_check_io_state(png_ptr, length, PNG_IO_WRITING);
 #endif
 }
-#endif /* !PNG_STDIO_SUPPORTED */
+#endif /* !STDIO */

 /* This function is called when there is a warning, but the library thinks
 * it can continue anyway.  Replacement functions don't have to do anything
@@ -604,7 +605,7 @@ png_debug_free(png_structp png_ptr, png_voidp ptr)
      free(ptr);
   ptr = NULL;
 }
-#endif /* PNG_USER_MEM_SUPPORTED && PNG_DEBUG */
+#endif /* USER_MEM && DEBUG */
 /* END of code to test memory allocation/deallocation */


@@ -643,7 +644,7 @@ set_location(png_structp png_ptr, struct user_chunk_data *data, int what)
 {
   int location;

-   if ((data->location[0] & what) || (data->location[1] & what))
+   if ((data->location[0] & what) != 0 || (data->location[1] & what) != 0)
      return 0; /* already have one of these */

   /* Find where we are (the code below zeroes info_ptr to indicate that the
@@ -652,7 +653,7 @@ set_location(png_structp png_ptr, struct user_chunk_data *data, int what)
   if (data->info_ptr == NULL) /* after IDAT */
      location = what | after_IDAT;

-   else if (png_get_valid(png_ptr, data->info_ptr, PNG_INFO_PLTE))
+   else if (png_get_valid(png_ptr, data->info_ptr, PNG_INFO_PLTE) != 0)
      location = what | before_IDAT;

   else
@@ -699,7 +700,7 @@ read_user_chunk_callback(png_struct *png_ptr, png_unknown_chunkp chunk)
         if (chunk->data[0] != 0 && chunk->data[0] != 1)
            return (-1);  /* Invalid mode */

-         if (set_location(png_ptr, my_user_chunk_data, have_sTER))
+         if (set_location(png_ptr, my_user_chunk_data, have_sTER) != 0)
         {
            my_user_chunk_data->sTER_mode=chunk->data[0];
            return (1);
@@ -718,7 +719,7 @@ read_user_chunk_callback(png_struct *png_ptr, png_unknown_chunkp chunk)
   if (chunk->size != 9)
      return (-1); /* Error return */

-   if (!set_location(png_ptr, my_user_chunk_data, have_vpAg))
+   if (set_location(png_ptr, my_user_chunk_data, have_vpAg) == 0)
      return (0);  /* duplicate vpAg */

   my_user_chunk_data->vpAg_width = png_get_uint_31(png_ptr, chunk->data);
@@ -779,8 +780,8 @@ write_chunks(png_structp write_ptr, int location)
         write_vpAg_chunk(write_ptr);
   }
 }
-#endif /* PNG_WRITE_SUPPORTED */
-#else /* !PNG_READ_USER_CHUNKS_SUPPORTED */
+#endif /* WRITE */
+#else /* !READ_USER_CHUNKS */
 #  define write_chunks(pp,loc) ((void)0)
 #endif
 /* END of code to demonstrate user chunk support */
@@ -1049,7 +1050,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      int interlace_type, compression_type, filter_type;

      if (png_get_IHDR(read_ptr, read_info_ptr, &width, &height, &bit_depth,
-          &color_type, &interlace_type, &compression_type, &filter_type))
+          &color_type, &interlace_type, &compression_type, &filter_type) != 0)
      {
         png_set_IHDR(write_ptr, write_info_ptr, width, height, bit_depth,
            color_type, interlace_type, compression_type, filter_type);
@@ -1082,7 +1083,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
         blue_y;

      if (png_get_cHRM_fixed(read_ptr, read_info_ptr, &white_x, &white_y,
-         &red_x, &red_y, &green_x, &green_y, &blue_x, &blue_y))
+         &red_x, &red_y, &green_x, &green_y, &blue_x, &blue_y) != 0)
      {
         png_set_cHRM_fixed(write_ptr, write_info_ptr, white_x, white_y, red_x,
            red_y, green_x, green_y, blue_x, blue_y);
@@ -1093,7 +1094,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      png_fixed_point gamma;

-      if (png_get_gAMA_fixed(read_ptr, read_info_ptr, &gamma))
+      if (png_get_gAMA_fixed(read_ptr, read_info_ptr, &gamma) != 0)
         png_set_gAMA_fixed(write_ptr, write_info_ptr, gamma);
   }
 #endif
@@ -1105,7 +1106,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
         blue_y;

      if (png_get_cHRM(read_ptr, read_info_ptr, &white_x, &white_y, &red_x,
-         &red_y, &green_x, &green_y, &blue_x, &blue_y))
+         &red_y, &green_x, &green_y, &blue_x, &blue_y) != 0)
      {
         png_set_cHRM(write_ptr, write_info_ptr, white_x, white_y, red_x,
            red_y, green_x, green_y, blue_x, blue_y);
@@ -1116,7 +1117,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      double gamma;

-      if (png_get_gAMA(read_ptr, read_info_ptr, &gamma))
+      if (png_get_gAMA(read_ptr, read_info_ptr, &gamma) != 0)
         png_set_gAMA(write_ptr, write_info_ptr, gamma);
   }
 #endif
@@ -1130,7 +1131,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      int compression_type;

      if (png_get_iCCP(read_ptr, read_info_ptr, &name, &compression_type,
-                      &profile, &proflen))
+                      &profile, &proflen) != 0)
      {
         png_set_iCCP(write_ptr, write_info_ptr, name, compression_type,
                      profile, proflen);
@@ -1141,7 +1142,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      int intent;

-      if (png_get_sRGB(read_ptr, read_info_ptr, &intent))
+      if (png_get_sRGB(read_ptr, read_info_ptr, &intent) != 0)
         png_set_sRGB(write_ptr, write_info_ptr, intent);
   }
 #endif
@@ -1149,14 +1150,14 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      png_colorp palette;
      int num_palette;

-      if (png_get_PLTE(read_ptr, read_info_ptr, &palette, &num_palette))
+      if (png_get_PLTE(read_ptr, read_info_ptr, &palette, &num_palette) != 0)
         png_set_PLTE(write_ptr, write_info_ptr, palette, num_palette);
   }
 #ifdef PNG_bKGD_SUPPORTED
   {
      png_color_16p background;

-      if (png_get_bKGD(read_ptr, read_info_ptr, &background))
+      if (png_get_bKGD(read_ptr, read_info_ptr, &background) != 0)
      {
         png_set_bKGD(write_ptr, write_info_ptr, background);
      }
@@ -1166,7 +1167,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      png_uint_16p hist;

-      if (png_get_hIST(read_ptr, read_info_ptr, &hist))
+      if (png_get_hIST(read_ptr, read_info_ptr, &hist) != 0)
         png_set_hIST(write_ptr, write_info_ptr, hist);
   }
 #endif
@@ -1176,7 +1177,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      int unit_type;

      if (png_get_oFFs(read_ptr, read_info_ptr, &offset_x, &offset_y,
-          &unit_type))
+          &unit_type) != 0)
      {
         png_set_oFFs(write_ptr, write_info_ptr, offset_x, offset_y, unit_type);
      }
@@ -1190,7 +1191,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      int type, nparams;

      if (png_get_pCAL(read_ptr, read_info_ptr, &purpose, &X0, &X1, &type,
-         &nparams, &units, &params))
+         &nparams, &units, &params) != 0)
      {
         png_set_pCAL(write_ptr, write_info_ptr, purpose, X0, X1, type,
            nparams, units, params);
@@ -1202,7 +1203,8 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      png_uint_32 res_x, res_y;
      int unit_type;

-      if (png_get_pHYs(read_ptr, read_info_ptr, &res_x, &res_y, &unit_type))
+      if (png_get_pHYs(read_ptr, read_info_ptr, &res_x, &res_y,
+          &unit_type) != 0)
         png_set_pHYs(write_ptr, write_info_ptr, res_x, res_y, unit_type);
   }
 #endif
@@ -1210,7 +1212,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      png_color_8p sig_bit;

-      if (png_get_sBIT(read_ptr, read_info_ptr, &sig_bit))
+      if (png_get_sBIT(read_ptr, read_info_ptr, &sig_bit) != 0)
         png_set_sBIT(write_ptr, write_info_ptr, sig_bit);
   }
 #endif
@@ -1222,7 +1224,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      double scal_width, scal_height;

      if (png_get_sCAL(read_ptr, read_info_ptr, &unit, &scal_width,
-         &scal_height))
+         &scal_height) != 0)
      {
         png_set_sCAL(write_ptr, write_info_ptr, unit, scal_width, scal_height);
      }
@@ -1234,7 +1236,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      png_charp scal_width, scal_height;

      if (png_get_sCAL_s(read_ptr, read_info_ptr, &unit, &scal_width,
-          &scal_height))
+          &scal_height) != 0)
      {
         png_set_sCAL_s(write_ptr, write_info_ptr, unit, scal_width,
             scal_height);
@@ -1274,11 +1276,11 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      png_timep mod_time;

-      if (png_get_tIME(read_ptr, read_info_ptr, &mod_time))
+      if (png_get_tIME(read_ptr, read_info_ptr, &mod_time) != 0)
      {
         png_set_tIME(write_ptr, write_info_ptr, mod_time);
 #ifdef PNG_TIME_RFC1123_SUPPORTED
-         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time))
+         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time) != 0)
            tIME_string[(sizeof tIME_string) - 1] = '\0';

         else
@@ -1288,7 +1290,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
         }

         tIME_chunk_present++;
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
      }
   }
 #endif
@@ -1299,7 +1301,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
      png_color_16p trans_color;

      if (png_get_tRNS(read_ptr, read_info_ptr, &trans_alpha, &num_trans,
-         &trans_color))
+         &trans_color) != 0)
      {
         int sample_max = (1 << bit_depth);
         /* libpng doesn't reject a tRNS chunk with out-of-range samples */
@@ -1404,7 +1406,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
         t_encode += (t_stop - t_start);
         t_start = t_stop;
 #endif
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */

 #ifndef SINGLE_ROWBUF_ALLOC
         pngtest_debug2("Freeing row buffer (pass %d, y = %u)", pass, y);
@@ -1457,11 +1459,11 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
   {
      png_timep mod_time;

-      if (png_get_tIME(read_ptr, end_info_ptr, &mod_time))
+      if (png_get_tIME(read_ptr, end_info_ptr, &mod_time) != 0)
      {
         png_set_tIME(write_ptr, write_end_info_ptr, mod_time);
 #ifdef PNG_TIME_RFC1123_SUPPORTED
-         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time))
+         if (png_convert_to_rfc1123_buffer(tIME_string, mod_time) != 0)
            tIME_string[(sizeof tIME_string) - 1] = '\0';

         else
@@ -1471,7 +1473,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
         }

         tIME_chunk_present++;
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
      }
   }
 #endif
@@ -1676,7 +1678,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
         }
      }
   }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */

   FCLOSE(fpin);
   FCLOSE(fpout);
@@ -1699,6 +1701,8 @@ main(int argc, char *argv[])
   int multiple = 0;
   int ierror = 0;

+   png_structp dummy_ptr;
+
   fprintf(STDERR, "\n Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);
   fprintf(STDERR, "   with zlib   version %s\n", ZLIB_VERSION);
   fprintf(STDERR, "%s", png_get_copyright(NULL));
@@ -1824,7 +1828,7 @@ main(int argc, char *argv[])
 #endif
 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
            for (k = 0; k<256; k++)
-               if (filters_used[k])
+               if (filters_used[k] != 0)
                  fprintf(STDERR, " Filter %d was used %lu times\n",
                     k, (unsigned long)filters_used[k]);
 #endif
@@ -1833,7 +1837,7 @@ main(int argc, char *argv[])
            fprintf(STDERR, " tIME = %s\n", tIME_string);

         tIME_chunk_present = 0;
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
         }

         else
@@ -1915,14 +1919,14 @@ main(int argc, char *argv[])
 #endif
 #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED
                for (k = 0; k<256; k++)
-                   if (filters_used[k])
+                   if (filters_used[k] != 0)
                      fprintf(STDERR, " Filter %d was used %lu times\n",
                         k, (unsigned long)filters_used[k]);
 #endif
 #ifdef PNG_TIME_RFC1123_SUPPORTED
             if (tIME_chunk_present != 0)
                fprintf(STDERR, " tIME = %s\n", tIME_string);
-#endif /* PNG_TIME_RFC1123_SUPPORTED */
+#endif /* TIME_RFC1123 */
            }
         }

@@ -1992,6 +1996,24 @@ main(int argc, char *argv[])
   else
      fprintf(STDERR, " libpng FAILS test\n");

+   dummy_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+   fprintf(STDERR, " Default limits:\n");
+   fprintf(STDERR, "  width_max  = %lu\n",
+      (unsigned long) png_get_user_width_max(dummy_ptr));
+   fprintf(STDERR, "  height_max = %lu\n",
+      (unsigned long) png_get_user_height_max(dummy_ptr));
+   if (png_get_chunk_cache_max(dummy_ptr) == 0)
+      fprintf(STDERR, "  cache_max  = unlimited\n");
+   else
+      fprintf(STDERR, "  cache_max  = %lu\n",
+         (unsigned long) png_get_chunk_cache_max(dummy_ptr));
+   if (png_get_chunk_malloc_max(dummy_ptr) == 0)
+      fprintf(STDERR, "  malloc_max = unlimited\n");
+   else
+      fprintf(STDERR, "  malloc_max = %lu\n",
+         (unsigned long) png_get_chunk_malloc_max(dummy_ptr));
+   png_destroy_read_struct(&dummy_ptr, NULL, NULL);
+
   return (int)(ierror != 0);
 }
 #else
@@ -2006,4 +2028,4 @@ main(void)
 #endif

 /* Generate a compiler error if there is an old png.h in the search path. */
-typedef png_libpng_version_1_6_15beta01 Your_png_h_is_not_version_1_6_15beta01;
+typedef png_libpng_version_1_6_17beta03 Your_png_h_is_not_version_1_6_17beta03;
--- a/pngtrans.c
+++ b/pngtrans.c
@@ -1,7 +1,7 @@

 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
 *
- * Last changed in libpng 1.6.11 [June 5, 2014]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -100,7 +100,7 @@ png_set_interlace_handling(png_structrp png_ptr)
 {
   png_debug(1, "in png_set_interlace handling");

-   if (png_ptr && png_ptr->interlaced)
+   if (png_ptr != 0 && png_ptr->interlaced != 0)
   {
      png_ptr->transformations |= PNG_INTERLACE;
      return (7);
@@ -127,7 +127,7 @@ png_set_filler(png_structrp png_ptr, png_uint_32 filler, int filler_loc)
   /* In libpng 1.6 it is possible to determine whether this is a read or write
    * operation and therefore to do more checking here for a valid call.
    */
-   if (png_ptr->mode & PNG_IS_READ_STRUCT)
+   if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0)
   {
 #     ifdef PNG_READ_FILLER_SUPPORTED
         /* On read png_set_filler is always valid, regardless of the base PNG
@@ -210,7 +210,7 @@ png_set_add_alpha(png_structrp png_ptr, png_uint_32 filler, int filler_loc)

   png_set_filler(png_ptr, filler, filler_loc);
   /* The above may fail to do anything. */
-   if (png_ptr->transformations & PNG_FILLER)
+   if ((png_ptr->transformations & PNG_FILLER) != 0)
      png_ptr->transformations |= PNG_ADD_ALPHA;
 }

@@ -478,7 +478,7 @@ png_do_packswap(png_row_infop row_info, png_bytep row)
         *rp = table[*rp];
   }
 }
-#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */
+#endif /* PACKSWAP || WRITE_PACKSWAP */

 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
@@ -605,7 +605,7 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
 {
   png_debug(1, "in png_do_bgr");

-   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
+   if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
   {
      png_uint_32 row_width = row_info->width;
      if (row_info->bit_depth == 8)
@@ -675,7 +675,7 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
 #endif
   }
 }
-#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+#endif /* READ_BGR || WRITE_BGR */

 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
@@ -778,7 +778,7 @@ png_do_check_palette_indexes(png_structrp png_ptr, png_row_infop row_info)
      }
   }
 }
-#endif /* PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED */
+#endif /* CHECK_FOR_INVALID_INDEX */

 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
@@ -844,7 +844,6 @@ png_get_current_pass_number(png_const_structrp png_ptr)
      return png_ptr->pass;
   return 8; /* invalid */
 }
-#endif /* PNG_USER_TRANSFORM_INFO_SUPPORTED */
-#endif /* PNG_READ_USER_TRANSFORM_SUPPORTED ||
-          PNG_WRITE_USER_TRANSFORM_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */
+#endif /* USER_TRANSFORM_INFO */
+#endif /* READ_USER_TRANSFORM || WRITE_USER_TRANSFORM */
+#endif /* READ || WRITE */
--- a/pngusr.dfa
+++ b/pngusr.dfa
@@ -8,7 +8,7 @@
 # here by entering the appropriate values as #defines preceded by '@' (to cause,
 # them to be passed through to the build of pnglibconf.h), for example:
 #
-# @# define PNG_USER_WIDTH_MAX 1000000
-# @# define PNG_USER_HEIGHT_MAX 1000000
-# @# define PNG_USER_CHUNK_CACHE_MAX 128
-# @# define PNG_USER_CHUNK_MALLOC_MAX 8000000
+# @# define PNG_USER_WIDTH_MAX 65535
+# @# define PNG_USER_HEIGHT_MAX 65535
+# @# define PNG_USER_CHUNK_CACHE_MAX 256
+# @# define PNG_USER_CHUNK_MALLOC_MAX 640000
--- a/pngwio.c
+++ b/pngwio.c
@@ -1,7 +1,7 @@

 /* pngwio.c - functions for data output
 *
- * Last changed in libpng 1.6.9 [February 6, 2014]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -151,7 +151,7 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
 #  endif
 #else
   PNG_UNUSED(output_flush_fn)
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+#endif /* WRITE_FLUSH */

 #ifdef PNG_READ_SUPPORTED
   /* It is an error to read while writing a png file */
@@ -165,4 +165,4 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
   }
 #endif
 }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */
--- a/pngwrite.c
+++ b/pngwrite.c
@@ -1,7 +1,7 @@

 /* pngwrite.c - general routines to write a PNG file
 *
- * Last changed in libpng 1.6.15 [(PENDING RELEASE)]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -24,7 +24,7 @@ static void
 write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
   unsigned int where)
 {
-   if (info_ptr->unknown_chunks_num)
+   if (info_ptr->unknown_chunks_num != 0)
   {
      png_const_unknown_chunkp up;

@@ -33,7 +33,7 @@ write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
      for (up = info_ptr->unknown_chunks;
           up < info_ptr->unknown_chunks + info_ptr->unknown_chunks_num;
           ++up)
-         if (up->location & where)
+         if ((up->location & where) != 0)
      {
         /* If per-chunk unknown chunk handling is enabled use it, otherwise
          * just write the chunks the application has set.
@@ -69,7 +69,7 @@ write_unknown_chunks(png_structrp png_ptr, png_const_inforp info_ptr,
      }
   }
 }
-#endif /* PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED */
+#endif /* WRITE_UNKNOWN_CHUNKS */

 /* Writes all the PNG information.  This is the suggested way to use the
 * library.  If you have a new chunk to add, make a function to write it,
@@ -88,14 +88,14 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
   if (png_ptr == NULL || info_ptr == NULL)
      return;

-   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+   if ((png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE) == 0)
   {
   /* Write PNG signature */
   png_write_sig(png_ptr);

 #ifdef PNG_MNG_FEATURES_SUPPORTED
-   if ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) && \
-       (png_ptr->mng_features_permitted))
+   if ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) != 0 && \
+       png_ptr->mng_features_permitted != 0)
   {
      png_warning(png_ptr, "MNG features are not allowed in a PNG datastream");
      png_ptr->mng_features_permitted = 0;
@@ -129,9 +129,9 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
    */
 #ifdef PNG_GAMMA_SUPPORTED
 #  ifdef PNG_WRITE_gAMA_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) &&
-         (info_ptr->valid & PNG_INFO_gAMA))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+          (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_gAMA) != 0 &&
+          (info_ptr->valid & PNG_INFO_gAMA) != 0)
         png_write_gAMA_fixed(png_ptr, info_ptr->colorspace.gamma);
 #  endif
 #endif
@@ -141,11 +141,11 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
    * and it matches one of the known sRGB ones issue a warning.
    */
 #  ifdef PNG_WRITE_iCCP_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->valid & PNG_INFO_iCCP))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+          (info_ptr->valid & PNG_INFO_iCCP) != 0)
      {
 #        ifdef PNG_WRITE_sRGB_SUPPORTED
-            if (info_ptr->valid & PNG_INFO_sRGB)
+            if ((info_ptr->valid & PNG_INFO_sRGB) != 0)
               png_app_warning(png_ptr,
                  "profile matches sRGB but writing iCCP instead");
 #        endif
@@ -159,22 +159,22 @@ png_write_info_before_PLTE(png_structrp png_ptr, png_const_inforp info_ptr)
 #  endif

 #  ifdef PNG_WRITE_sRGB_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->valid & PNG_INFO_sRGB))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+          (info_ptr->valid & PNG_INFO_sRGB) != 0)
         png_write_sRGB(png_ptr, info_ptr->colorspace.rendering_intent);
 #  endif /* WRITE_sRGB */
 #endif /* COLORSPACE */

 #ifdef PNG_WRITE_sBIT_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_sBIT)
+   if ((info_ptr->valid & PNG_INFO_sBIT) != 0)
      png_write_sBIT(png_ptr, &(info_ptr->sig_bit), info_ptr->color_type);
 #endif

 #ifdef PNG_COLORSPACE_SUPPORTED
 #  ifdef PNG_WRITE_cHRM_SUPPORTED
-      if (!(info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) &&
-         (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) &&
-         (info_ptr->valid & PNG_INFO_cHRM))
+      if ((info_ptr->colorspace.flags & PNG_COLORSPACE_INVALID) == 0 &&
+         (info_ptr->colorspace.flags & PNG_COLORSPACE_FROM_cHRM) != 0 &&
+         (info_ptr->valid & PNG_INFO_cHRM) != 0)
         png_write_cHRM_fixed(png_ptr, &info_ptr->colorspace.end_points_xy);
 #  endif
 #endif
@@ -201,19 +201,19 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)

   png_write_info_before_PLTE(png_ptr, info_ptr);

-   if (info_ptr->valid & PNG_INFO_PLTE)
+   if ((info_ptr->valid & PNG_INFO_PLTE) != 0)
      png_write_PLTE(png_ptr, info_ptr->palette,
          (png_uint_32)info_ptr->num_palette);

-   else if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+   else if ((info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) !=0)
      png_error(png_ptr, "Valid palette required for paletted images");

 #ifdef PNG_WRITE_tRNS_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_tRNS)
+   if ((info_ptr->valid & PNG_INFO_tRNS) !=0)
   {
 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
      /* Invert the alpha channel (in tRNS) */
-      if ((png_ptr->transformations & PNG_INVERT_ALPHA) &&
+      if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0 &&
          info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
      {
         int j;
@@ -227,42 +227,42 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
   }
 #endif
 #ifdef PNG_WRITE_bKGD_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_bKGD)
+   if ((info_ptr->valid & PNG_INFO_bKGD) != 0)
      png_write_bKGD(png_ptr, &(info_ptr->background), info_ptr->color_type);
 #endif

 #ifdef PNG_WRITE_hIST_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_hIST)
+   if ((info_ptr->valid & PNG_INFO_hIST) != 0)
      png_write_hIST(png_ptr, info_ptr->hist, info_ptr->num_palette);
 #endif

 #ifdef PNG_WRITE_oFFs_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_oFFs)
+   if ((info_ptr->valid & PNG_INFO_oFFs) != 0)
      png_write_oFFs(png_ptr, info_ptr->x_offset, info_ptr->y_offset,
          info_ptr->offset_unit_type);
 #endif

 #ifdef PNG_WRITE_pCAL_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_pCAL)
+   if ((info_ptr->valid & PNG_INFO_pCAL) != 0)
      png_write_pCAL(png_ptr, info_ptr->pcal_purpose, info_ptr->pcal_X0,
          info_ptr->pcal_X1, info_ptr->pcal_type, info_ptr->pcal_nparams,
          info_ptr->pcal_units, info_ptr->pcal_params);
 #endif

 #ifdef PNG_WRITE_sCAL_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_sCAL)
+   if ((info_ptr->valid & PNG_INFO_sCAL) != 0)
      png_write_sCAL_s(png_ptr, (int)info_ptr->scal_unit,
          info_ptr->scal_s_width, info_ptr->scal_s_height);
 #endif /* sCAL */

 #ifdef PNG_WRITE_pHYs_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_pHYs)
+   if ((info_ptr->valid & PNG_INFO_pHYs) != 0)
      png_write_pHYs(png_ptr, info_ptr->x_pixels_per_unit,
          info_ptr->y_pixels_per_unit, info_ptr->phys_unit_type);
 #endif /* pHYs */

 #ifdef PNG_WRITE_tIME_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_tIME)
+   if ((info_ptr->valid & PNG_INFO_tIME) != 0)
   {
      png_write_tIME(png_ptr, &(info_ptr->mod_time));
      png_ptr->mode |= PNG_WROTE_tIME;
@@ -270,7 +270,7 @@ png_write_info(png_structrp png_ptr, png_const_inforp info_ptr)
 #endif /* tIME */

 #ifdef PNG_WRITE_sPLT_SUPPORTED
-   if (info_ptr->valid & PNG_INFO_sPLT)
+   if ((info_ptr->valid & PNG_INFO_sPLT) != 0)
      for (i = 0; i < (int)info_ptr->splt_palettes_num; i++)
         png_write_sPLT(png_ptr, info_ptr->splt_palettes + i);
 #endif /* sPLT */
@@ -351,7 +351,7 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
   if (png_ptr == NULL)
      return;

-   if (!(png_ptr->mode & PNG_HAVE_IDAT))
+   if ((png_ptr->mode & PNG_HAVE_IDAT) == 0)
      png_error(png_ptr, "No IDATs written into file");

 #ifdef PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
@@ -367,8 +367,8 @@ png_write_end(png_structrp png_ptr, png_inforp info_ptr)
 #endif
 #ifdef PNG_WRITE_tIME_SUPPORTED
      /* Check to see if user has supplied a time chunk */
-      if ((info_ptr->valid & PNG_INFO_tIME) &&
-          !(png_ptr->mode & PNG_WROTE_tIME))
+      if ((info_ptr->valid & PNG_INFO_tIME) != 0 &&
+          (png_ptr->mode & PNG_WROTE_tIME) == 0)
         png_write_tIME(png_ptr, &(info_ptr->mod_time));

 #endif
@@ -497,7 +497,7 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
 {
   png_structrp png_ptr = png_create_png_struct(user_png_ver, error_ptr,
       error_fn, warn_fn, mem_ptr, malloc_fn, free_fn);
-#endif /* PNG_USER_MEM_SUPPORTED */
+#endif /* USER_MEM */
   if (png_ptr != NULL)
   {
      /* Set the zlib control values to defaults; they can be overridden by the
@@ -521,7 +521,7 @@ png_create_write_struct_2,(png_const_charp user_png_ver, png_voidp error_ptr,
      png_ptr->zlib_text_mem_level = 8;
      png_ptr->zlib_text_window_bits = 15;
      png_ptr->zlib_text_method = 8;
-#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
+#endif /* WRITE_COMPRESSED_TEXT */

      /* This is a highly dubious configuration option; by default it is off,
       * but it may be appropriate for private builds that are testing
@@ -618,7 +618,7 @@ png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
 {
   png_debug(1, "in png_do_write_intrapixel");

-   if ((row_info->color_type & PNG_COLOR_MASK_COLOR))
+   if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
   {
      int bytes_per_pixel;
      png_uint_32 row_width = row_info->width;
@@ -671,10 +671,10 @@ png_do_write_intrapixel(png_row_infop row_info, png_bytep row)
            *(rp + 5) = (png_byte)(blue & 0xff);
         }
      }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
   }
 }
-#endif /* PNG_MNG_FEATURES_SUPPORTED */
+#endif /* MNG_FEATURES */

 /* Called by user to write a row of image data */
 void PNGAPI
@@ -693,44 +693,44 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
   if (png_ptr->row_number == 0 && png_ptr->pass == 0)
   {
      /* Make sure we wrote the header info */
-      if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+      if ((png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE) == 0)
         png_error(png_ptr,
             "png_write_info was never called before png_write_row");

      /* Check for transforms that have been set but were defined out */
 #if !defined(PNG_WRITE_INVERT_SUPPORTED) && defined(PNG_READ_INVERT_SUPPORTED)
-      if (png_ptr->transformations & PNG_INVERT_MONO)
+      if ((png_ptr->transformations & PNG_INVERT_MONO) != 0)
         png_warning(png_ptr, "PNG_WRITE_INVERT_SUPPORTED is not defined");
 #endif

 #if !defined(PNG_WRITE_FILLER_SUPPORTED) && defined(PNG_READ_FILLER_SUPPORTED)
-      if (png_ptr->transformations & PNG_FILLER)
+      if ((png_ptr->transformations & PNG_FILLER) != 0)
         png_warning(png_ptr, "PNG_WRITE_FILLER_SUPPORTED is not defined");
 #endif
 #if !defined(PNG_WRITE_PACKSWAP_SUPPORTED) && \
    defined(PNG_READ_PACKSWAP_SUPPORTED)
-      if (png_ptr->transformations & PNG_PACKSWAP)
+      if ((png_ptr->transformations & PNG_PACKSWAP) != 0)
         png_warning(png_ptr,
             "PNG_WRITE_PACKSWAP_SUPPORTED is not defined");
 #endif

 #if !defined(PNG_WRITE_PACK_SUPPORTED) && defined(PNG_READ_PACK_SUPPORTED)
-      if (png_ptr->transformations & PNG_PACK)
+      if ((png_ptr->transformations & PNG_PACK) != 0)
         png_warning(png_ptr, "PNG_WRITE_PACK_SUPPORTED is not defined");
 #endif

 #if !defined(PNG_WRITE_SHIFT_SUPPORTED) && defined(PNG_READ_SHIFT_SUPPORTED)
-      if (png_ptr->transformations & PNG_SHIFT)
+      if ((png_ptr->transformations & PNG_SHIFT) != 0)
         png_warning(png_ptr, "PNG_WRITE_SHIFT_SUPPORTED is not defined");
 #endif

 #if !defined(PNG_WRITE_BGR_SUPPORTED) && defined(PNG_READ_BGR_SUPPORTED)
-      if (png_ptr->transformations & PNG_BGR)
+      if ((png_ptr->transformations & PNG_BGR) != 0)
         png_warning(png_ptr, "PNG_WRITE_BGR_SUPPORTED is not defined");
 #endif

 #if !defined(PNG_WRITE_SWAP_SUPPORTED) && defined(PNG_READ_SWAP_SUPPORTED)
-      if (png_ptr->transformations & PNG_SWAP_BYTES)
+      if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0)
         png_warning(png_ptr, "PNG_WRITE_SWAP_SUPPORTED is not defined");
 #endif

@@ -739,12 +739,13 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)

 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
   /* If interlaced and not interested in row, return */
-   if (png_ptr->interlaced && (png_ptr->transformations & PNG_INTERLACE))
+   if (png_ptr->interlaced != 0 &&
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
   {
      switch (png_ptr->pass)
      {
         case 0:
-            if (png_ptr->row_number & 0x07)
+            if ((png_ptr->row_number & 0x07) != 0)
            {
               png_write_finish_row(png_ptr);
               return;
@@ -752,7 +753,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
            break;

         case 1:
-            if ((png_ptr->row_number & 0x07) || png_ptr->width < 5)
+            if ((png_ptr->row_number & 0x07) != 0 || png_ptr->width < 5)
            {
               png_write_finish_row(png_ptr);
               return;
@@ -768,7 +769,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
            break;

         case 3:
-            if ((png_ptr->row_number & 0x03) || png_ptr->width < 3)
+            if ((png_ptr->row_number & 0x03) != 0 || png_ptr->width < 3)
            {
               png_write_finish_row(png_ptr);
               return;
@@ -784,7 +785,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
            break;

         case 5:
-            if ((png_ptr->row_number & 0x01) || png_ptr->width < 2)
+            if ((png_ptr->row_number & 0x01) != 0 || png_ptr->width < 2)
            {
               png_write_finish_row(png_ptr);
               return;
@@ -792,7 +793,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
            break;

         case 6:
-            if (!(png_ptr->row_number & 0x01))
+            if ((png_ptr->row_number & 0x01) == 0)
            {
               png_write_finish_row(png_ptr);
               return;
@@ -826,7 +827,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
   /* Handle interlacing */
   if (png_ptr->interlaced && png_ptr->pass < 6 &&
-       (png_ptr->transformations & PNG_INTERLACE))
+       (png_ptr->transformations & PNG_INTERLACE) != 0)
   {
      png_do_write_interlace(&row_info, png_ptr->row_buf + 1, png_ptr->pass);
      /* This should always get caught above, but still ... */
@@ -840,7 +841,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)

 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
   /* Handle other transformations */
-   if (png_ptr->transformations)
+   if (png_ptr->transformations != 0)
      png_do_write_transformations(png_ptr, &row_info);
 #endif

@@ -861,7 +862,7 @@ png_write_row(png_structrp png_ptr, png_const_bytep row)
    * 4. The filter_method is 64 and
    * 5. The color_type is RGB or RGBA
    */
-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
       (png_ptr->filter_type == PNG_INTRAPIXEL_DIFFERENCING))
   {
      /* Intrapixel differencing */
@@ -914,7 +915,7 @@ png_write_flush(png_structrp png_ptr)
   png_ptr->flush_rows = 0;
   png_flush(png_ptr);
 }
-#endif /* PNG_WRITE_FLUSH_SUPPORTED */
+#endif /* WRITE_FLUSH */

 #ifdef PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
 static void png_reset_filter_heuristics(png_structrp png_ptr);/* forward decl */
@@ -927,7 +928,7 @@ png_write_destroy(png_structrp png_ptr)
   png_debug(1, "in png_write_destroy");

   /* Free any memory zlib uses */
-   if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
+   if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
      deflateEnd(&png_ptr->zstream);

   /* Free our memory.  png_free checks NULL for us. */
@@ -1004,7 +1005,7 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
      return;

 #ifdef PNG_MNG_FEATURES_SUPPORTED
-   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
+   if ((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
       (method == PNG_INTRAPIXEL_DIFFERENCING))
      method = PNG_FILTER_TYPE_BASE;

@@ -1018,7 +1019,7 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
         case 6:
         case 7: png_app_error(png_ptr, "Unknown row filter for method 0");
            /* FALL THROUGH */
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
         case PNG_FILTER_VALUE_NONE:
            png_ptr->do_filter = PNG_FILTER_NONE; break;

@@ -1040,7 +1041,7 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
 #else
         default:
            png_app_error(png_ptr, "Unknown row filter for method 0");
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
      }

      /* If we have allocated the row_buf, this means we have already started
@@ -1055,14 +1056,16 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
      if (png_ptr->row_buf != NULL)
      {
 #ifdef PNG_WRITE_FILTER_SUPPORTED
-         if ((png_ptr->do_filter & PNG_FILTER_SUB) && png_ptr->sub_row == NULL)
+         if ((png_ptr->do_filter & PNG_FILTER_SUB) != 0 &&
+             png_ptr->sub_row == NULL)
         {
            png_ptr->sub_row = (png_bytep)png_malloc(png_ptr,
                (png_ptr->rowbytes + 1));
            png_ptr->sub_row[0] = PNG_FILTER_VALUE_SUB;
         }

-         if ((png_ptr->do_filter & PNG_FILTER_UP) && png_ptr->up_row == NULL)
+         if ((png_ptr->do_filter & PNG_FILTER_UP) != 0 &&
+              png_ptr->up_row == NULL)
         {
            if (png_ptr->prev_row == NULL)
            {
@@ -1079,7 +1082,8 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
            }
         }

-         if ((png_ptr->do_filter & PNG_FILTER_AVG) && png_ptr->avg_row == NULL)
+         if ((png_ptr->do_filter & PNG_FILTER_AVG) != 0 &&
+              png_ptr->avg_row == NULL)
         {
            if (png_ptr->prev_row == NULL)
            {
@@ -1096,7 +1100,7 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
            }
         }

-         if ((png_ptr->do_filter & PNG_FILTER_PAETH) &&
+         if ((png_ptr->do_filter & PNG_FILTER_PAETH) != 0 &&
             png_ptr->paeth_row == NULL)
         {
            if (png_ptr->prev_row == NULL)
@@ -1114,7 +1118,7 @@ png_set_filter(png_structrp png_ptr, int method, int filters)
         }

         if (png_ptr->do_filter == PNG_NO_FILTERS)
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
            png_ptr->do_filter = PNG_FILTER_NONE;
      }
   }
@@ -1257,7 +1261,7 @@ png_set_filter_heuristics(png_structrp png_ptr, int heuristic_method,
   /* The internal API allocates all the arrays and ensures that the elements of
    * those arrays are set to the default value.
    */
-   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
+   if (png_init_filter_heuristics(png_ptr, heuristic_method, num_weights) == 0)
      return;

   /* If using the weighted method copy in the weights. */
@@ -1312,7 +1316,7 @@ png_set_filter_heuristics_fixed(png_structrp png_ptr, int heuristic_method,
   /* The internal API allocates all the arrays and ensures that the elements of
    * those arrays are set to the default value.
    */
-   if (!png_init_filter_heuristics(png_ptr, heuristic_method, num_weights))
+   if (png_init_filter_heuristics(png_ptr, heuristic_method, num_weights) == 0)
      return;

   /* If using the weighted method copy in the weights. */
@@ -1366,7 +1370,7 @@ png_set_filter_heuristics_fixed(png_structrp png_ptr, int heuristic_method,
   }
 }
 #endif /* FIXED_POINT */
-#endif /* PNG_WRITE_WEIGHTED_FILTER_SUPPORTED */
+#endif /* WRITE_WEIGHTED_FILTER */

 void PNGAPI
 png_set_compression_level(png_structrp png_ptr, int level)
@@ -1523,7 +1527,7 @@ png_set_text_compression_method(png_structrp png_ptr, int method)

   png_ptr->zlib_text_method = method;
 }
-#endif /* PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED */
+#endif /* WRITE_CUSTOMIZE_ZTXT_COMPRESSION */
 /* end of API added to libpng-1.5.4 */

 void PNGAPI
@@ -1571,7 +1575,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
   /* ------ these transformations don't touch the info structure ------- */

   /* Invert monochrome pixels */
-   if (transforms & PNG_TRANSFORM_INVERT_MONO)
+   if ((transforms & PNG_TRANSFORM_INVERT_MONO) != 0)
 #ifdef PNG_WRITE_INVERT_SUPPORTED
      png_set_invert_mono(png_ptr);
 #else
@@ -1581,16 +1585,16 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
   /* Shift the pixels up to a legal bit depth and fill in
    * as appropriate to correctly scale the image.
    */
-   if (transforms & PNG_TRANSFORM_SHIFT)
+   if ((transforms & PNG_TRANSFORM_SHIFT) != 0)
 #ifdef PNG_WRITE_SHIFT_SUPPORTED
-      if (info_ptr->valid & PNG_INFO_sBIT)
+      if ((info_ptr->valid & PNG_INFO_sBIT) != 0)
         png_set_shift(png_ptr, &info_ptr->sig_bit);
 #else
      png_app_error(png_ptr, "PNG_TRANSFORM_SHIFT not supported");
 #endif

   /* Pack pixels into bytes */
-   if (transforms & PNG_TRANSFORM_PACKING)
+   if ((transforms & PNG_TRANSFORM_PACKING) != 0)
 #ifdef PNG_WRITE_PACK_SUPPORTED
      png_set_packing(png_ptr);
 #else
@@ -1598,7 +1602,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

   /* Swap location of alpha bytes from ARGB to RGBA */
-   if (transforms & PNG_TRANSFORM_SWAP_ALPHA)
+   if ((transforms & PNG_TRANSFORM_SWAP_ALPHA) != 0)
 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
      png_set_swap_alpha(png_ptr);
 #else
@@ -1609,13 +1613,13 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
    * RGB, note that the code expects the input color type to be G or RGB; no
    * alpha channel.
    */
-   if (transforms &
-      (PNG_TRANSFORM_STRIP_FILLER_AFTER|PNG_TRANSFORM_STRIP_FILLER_BEFORE))
+   if ((transforms & (PNG_TRANSFORM_STRIP_FILLER_AFTER|
+      PNG_TRANSFORM_STRIP_FILLER_BEFORE)) != 0)
   {
 #ifdef PNG_WRITE_FILLER_SUPPORTED
-      if (transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER)
+      if ((transforms & PNG_TRANSFORM_STRIP_FILLER_AFTER) != 0)
      {
-         if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)
+         if ((transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) != 0)
            png_app_error(png_ptr,
               "PNG_TRANSFORM_STRIP_FILLER: BEFORE+AFTER not supported");

@@ -1623,7 +1627,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
         png_set_filler(png_ptr, 0, PNG_FILLER_AFTER);
      }

-      else if (transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE)
+      else if ((transforms & PNG_TRANSFORM_STRIP_FILLER_BEFORE) != 0)
         png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
 #else
      png_app_error(png_ptr, "PNG_TRANSFORM_STRIP_FILLER not supported");
@@ -1631,7 +1635,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
   }

   /* Flip BGR pixels to RGB */
-   if (transforms & PNG_TRANSFORM_BGR)
+   if ((transforms & PNG_TRANSFORM_BGR) != 0)
 #ifdef PNG_WRITE_BGR_SUPPORTED
      png_set_bgr(png_ptr);
 #else
@@ -1639,7 +1643,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

   /* Swap bytes of 16-bit files to most significant byte first */
-   if (transforms & PNG_TRANSFORM_SWAP_ENDIAN)
+   if ((transforms & PNG_TRANSFORM_SWAP_ENDIAN) != 0)
 #ifdef PNG_WRITE_SWAP_SUPPORTED
      png_set_swap(png_ptr);
 #else
@@ -1647,7 +1651,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

   /* Swap bits of 1, 2, 4 bit packed pixel formats */
-   if (transforms & PNG_TRANSFORM_PACKSWAP)
+   if ((transforms & PNG_TRANSFORM_PACKSWAP) != 0)
 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED
      png_set_packswap(png_ptr);
 #else
@@ -1655,7 +1659,7 @@ png_write_png(png_structrp png_ptr, png_inforp info_ptr,
 #endif

   /* Invert the alpha channel from opacity to transparency */
-   if (transforms & PNG_TRANSFORM_INVERT_ALPHA)
+   if ((transforms & PNG_TRANSFORM_INVERT_ALPHA) != 0)
 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
      png_set_invert_alpha(png_ptr);
 #else
@@ -1746,14 +1750,14 @@ png_write_image_16bit(png_voidp argument)
      display->first_row);
   png_uint_16p output_row = png_voidcast(png_uint_16p, display->local_row);
   png_uint_16p row_end;
-   const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
+   const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? 3 : 1;
   int aindex = 0;
   png_uint_32 y = image->height;

-   if (image->format & PNG_FORMAT_FLAG_ALPHA)
+   if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
   {
 #     ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
-         if (image->format & PNG_FORMAT_FLAG_AFIRST)
+         if ((image->format & PNG_FORMAT_FLAG_AFIRST) != 0)
         {
            aindex = -1;
            ++input_row; /* To point to the first component */
@@ -1903,15 +1907,15 @@ png_write_image_8bit(png_voidp argument)
      display->first_row);
   png_bytep output_row = png_voidcast(png_bytep, display->local_row);
   png_uint_32 y = image->height;
-   const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) ? 3 : 1;
+   const int channels = (image->format & PNG_FORMAT_FLAG_COLOR) != 0 ? 3 : 1;

-   if (image->format & PNG_FORMAT_FLAG_ALPHA)
+   if ((image->format & PNG_FORMAT_FLAG_ALPHA) != 0)
   {
      png_bytep row_end;
      int aindex;

 #     ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
-         if (image->format & PNG_FORMAT_FLAG_AFIRST)
+         if ((image->format & PNG_FORMAT_FLAG_AFIRST) != 0)
         {
            aindex = -1;
            ++input_row; /* To point to the first component */
@@ -2008,7 +2012,7 @@ png_image_set_PLTE(png_image_write_control *display)
 #  endif

 #  ifdef PNG_FORMAT_BGR_SUPPORTED
-      const int bgr = (format & PNG_FORMAT_FLAG_BGR) ? 2 : 0;
+      const int bgr = (format & PNG_FORMAT_FLAG_BGR) != 0 ? 2 : 0;
 #  else
 #     define bgr 0
 #  endif
@@ -2025,13 +2029,13 @@ png_image_set_PLTE(png_image_write_control *display)
      /* This gets automatically converted to sRGB with reversal of the
       * pre-multiplication if the color-map has an alpha channel.
       */
-      if (format & PNG_FORMAT_FLAG_LINEAR)
+      if ((format & PNG_FORMAT_FLAG_LINEAR) != 0)
      {
         png_const_uint_16p entry = png_voidcast(png_const_uint_16p, cmap);

         entry += i * channels;

-         if (channels & 1) /* no alpha */
+         if ((channels & 1) != 0) /* no alpha */
         {
            if (channels >= 3) /* RGB */
            {
@@ -2143,12 +2147,11 @@ png_image_write_main(png_voidp argument)
   png_inforp info_ptr = image->opaque->info_ptr;
   png_uint_32 format = image->format;

-   int colormap = (format & PNG_FORMAT_FLAG_COLORMAP) != 0;
-   /* input */
-   int linear = (colormap == 0) && (format & PNG_FORMAT_FLAG_LINEAR) != 0;
-   int alpha = (colormap == 0) && (format & PNG_FORMAT_FLAG_ALPHA) != 0;
-   int write_16bit = (linear != 0 ) && (colormap == 0) &&
-       (display->convert_to_8bit == 0);
+   /* The following four ints are actually booleans */
+   int colormap = (format & PNG_FORMAT_FLAG_COLORMAP);
+   int linear = !colormap && (format & PNG_FORMAT_FLAG_LINEAR); /* input */
+   int alpha = !colormap && (format & PNG_FORMAT_FLAG_ALPHA);
+   int write_16bit = linear && !colormap && (display->convert_to_8bit == 0);

 #  ifdef PNG_BENIGN_ERRORS_SUPPORTED
      /* Make sure we error out on any bad situation */
@@ -2160,7 +2163,7 @@ png_image_write_main(png_voidp argument)
      display->row_stride = PNG_IMAGE_ROW_STRIDE(*image);

   /* Set the required transforms then write the rows in the correct order. */
-   if (format & PNG_FORMAT_FLAG_COLORMAP)
+   if ((format & PNG_FORMAT_FLAG_COLORMAP) != 0)
   {
      if (display->colormap != NULL && image->colormap_entries > 0)
      {
@@ -2197,7 +2200,7 @@ png_image_write_main(png_voidp argument)
      /* The gamma here is 1.0 (linear) and the cHRM chunk matches sRGB. */
      png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_LINEAR);

-      if (!(image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB))
+      if ((image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB) == 0)
         png_set_cHRM_fixed(png_ptr, info_ptr,
            /* color      x       y */
            /* white */ 31270, 32900,
@@ -2207,7 +2210,7 @@ png_image_write_main(png_voidp argument)
         );
   }

-   else if (!(image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB))
+   else if ((image->flags & PNG_IMAGE_FLAG_COLORSPACE_NOT_sRGB) == 0)
      png_set_sRGB(png_ptr, info_ptr, PNG_sRGB_INTENT_PERCEPTUAL);

   /* Else writing an 8-bit file and the *colors* aren't sRGB, but the 8-bit
@@ -2228,12 +2231,12 @@ png_image_write_main(png_voidp argument)
   {
      PNG_CONST png_uint_16 le = 0x0001;

-      if (*(png_const_bytep)&le)
+      if ((*(png_const_bytep) & le) != 0)
         png_set_swap(png_ptr);
   }

 #  ifdef PNG_SIMPLIFIED_WRITE_BGR_SUPPORTED
-      if (format & PNG_FORMAT_FLAG_BGR)
+      if ((format & PNG_FORMAT_FLAG_BGR) != 0)
      {
         if (colormap == 0 && (format & PNG_FORMAT_FLAG_COLOR) != 0)
            png_set_bgr(png_ptr);
@@ -2242,7 +2245,7 @@ png_image_write_main(png_voidp argument)
 #  endif

 #  ifdef PNG_SIMPLIFIED_WRITE_AFIRST_SUPPORTED
-      if (format & PNG_FORMAT_FLAG_AFIRST)
+      if ((format & PNG_FORMAT_FLAG_AFIRST) != 0)
      {
         if (colormap == 0 && (format & PNG_FORMAT_FLAG_ALPHA) != 0)
            png_set_swap_alpha(png_ptr);
@@ -2253,7 +2256,7 @@ png_image_write_main(png_voidp argument)
   /* If there are 16 or fewer color-map entries we wrote a lower bit depth
    * above, but the application data is still byte packed.
    */
-   if (colormap && image->colormap_entries <= 16)
+   if (colormap != 0 && image->colormap_entries <= 16)
      png_set_packing(png_ptr);

   /* That should have handled all (both) the transforms. */
@@ -2341,7 +2344,7 @@ png_image_write_to_stdio(png_imagep image, FILE *file, int convert_to_8bit,
   {
      if (file != NULL)
      {
-         if (png_image_write_init(image))
+         if (png_image_write_init(image) != 0)
         {
            png_image_write_control display;
            int result;
@@ -2396,7 +2399,7 @@ png_image_write_to_file(png_imagep image, const char *file_name,
         if (fp != NULL)
         {
            if (png_image_write_to_stdio(image, fp, convert_to_8bit, buffer,
-               row_stride, colormap))
+               row_stride, colormap) != 0)
            {
               int error; /* from fflush/fclose */

@@ -2447,6 +2450,6 @@ png_image_write_to_file(png_imagep image, const char *file_name,
   else
      return 0;
 }
-#endif /* PNG_STDIO_SUPPORTED */
+#endif /* STDIO */
 #endif /* SIMPLIFIED_WRITE */
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */
--- a/pngwtran.c
+++ b/pngwtran.c
@@ -1,7 +1,7 @@

 /* pngwtran.c - transforms the data in a row for PNG writers
 *
- * Last changed in libpng 1.6.9 [February 6, 2014]
+ * Last changed in libpng 1.6.15 [November 20, 2014]
 * Copyright (c) 1998-2014 Glenn Randers-Pehrson
 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -177,7 +177,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
      int shift_start[4], shift_dec[4];
      int channels = 0;

-      if (row_info->color_type & PNG_COLOR_MASK_COLOR)
+      if ((row_info->color_type & PNG_COLOR_MASK_COLOR) != 0)
      {
         shift_start[channels] = row_info->bit_depth - bit_depth->red;
         shift_dec[channels] = bit_depth->red;
@@ -199,7 +199,7 @@ png_do_shift(png_row_infop row_info, png_bytep row,
         channels++;
      }

-      if (row_info->color_type & PNG_COLOR_MASK_ALPHA)
+      if ((row_info->color_type & PNG_COLOR_MASK_ALPHA) != 0)
      {
         shift_start[channels] = row_info->bit_depth - bit_depth->alpha;
         shift_dec[channels] = bit_depth->alpha;
@@ -353,7 +353,7 @@ png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
               *(dp++) = save[1];
            }
         }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
      }

      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -392,7 +392,7 @@ png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
               *(dp++) = save[1];
            }
         }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
      }
   }
 }
@@ -449,7 +449,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
               *(dp++) = (png_byte)(255 - *(sp++));
            }
         }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
      }

      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
@@ -487,7 +487,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
               *(dp++) = (png_byte)(255 - *(sp++));
            }
         }
-#endif /* PNG_WRITE_16BIT_SUPPORTED */
+#endif /* WRITE_16BIT */
      }
   }
 }
@@ -505,7 +505,7 @@ png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info)
      return;

 #ifdef PNG_WRITE_USER_TRANSFORM_SUPPORTED
-   if (png_ptr->transformations & PNG_USER_TRANSFORM)
+   if ((png_ptr->transformations & PNG_USER_TRANSFORM) != 0)
      if (png_ptr->write_user_transform_fn != NULL)
         (*(png_ptr->write_user_transform_fn)) /* User write transform
                                                 function */
@@ -521,52 +521,54 @@ png_do_write_transformations(png_structrp png_ptr, png_row_infop row_info)
 #endif

 #ifdef PNG_WRITE_FILLER_SUPPORTED
-   if (png_ptr->transformations & PNG_FILLER)
+   if ((png_ptr->transformations & PNG_FILLER) != 0)
      png_do_strip_channel(row_info, png_ptr->row_buf + 1,
         !(png_ptr->flags & PNG_FLAG_FILLER_AFTER));
 #endif

 #ifdef PNG_WRITE_PACKSWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_PACKSWAP)
+   if ((png_ptr->transformations & PNG_PACKSWAP) != 0)
      png_do_packswap(row_info, png_ptr->row_buf + 1);
 #endif

 #ifdef PNG_WRITE_PACK_SUPPORTED
-   if (png_ptr->transformations & PNG_PACK)
+   if ((png_ptr->transformations & PNG_PACK) != 0)
      png_do_pack(row_info, png_ptr->row_buf + 1,
          (png_uint_32)png_ptr->bit_depth);
 #endif

 #ifdef PNG_WRITE_SWAP_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
+#  ifdef PNG_16BIT_SUPPORTED
+   if ((png_ptr->transformations & PNG_SWAP_BYTES) != 0)
      png_do_swap(row_info, png_ptr->row_buf + 1);
+#  endif
 #endif

 #ifdef PNG_WRITE_SHIFT_SUPPORTED
-   if (png_ptr->transformations & PNG_SHIFT)
+   if ((png_ptr->transformations & PNG_SHIFT) != 0)
      png_do_shift(row_info, png_ptr->row_buf + 1,
          &(png_ptr->shift));
 #endif

 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_SWAP_ALPHA)
+   if ((png_ptr->transformations & PNG_SWAP_ALPHA) != 0)
      png_do_write_swap_alpha(row_info, png_ptr->row_buf + 1);
 #endif

 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_ALPHA)
+   if ((png_ptr->transformations & PNG_INVERT_ALPHA) != 0)
      png_do_write_invert_alpha(row_info, png_ptr->row_buf + 1);
 #endif

 #ifdef PNG_WRITE_BGR_SUPPORTED
-   if (png_ptr->transformations & PNG_BGR)
+   if ((png_ptr->transformations & PNG_BGR) != 0)
      png_do_bgr(row_info, png_ptr->row_buf + 1);
 #endif

 #ifdef PNG_WRITE_INVERT_SUPPORTED
-   if (png_ptr->transformations & PNG_INVERT_MONO)
+   if ((png_ptr->transformations & PNG_INVERT_MONO) != 0)
      png_do_invert(row_info, png_ptr->row_buf + 1);
 #endif
 }
-#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE_TRANSFORMS */
+#endif /* WRITE */
--- a/pngwutil.c
+++ b/pngwutil.c
@@ -1,8 +1,8 @@

 /* pngwutil.c - utilities to write a PNG file
 *
- * Last changed in libpng 1.6.14 [October 23, 2014]
- * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * Last changed in libpng 1.6.17 [(PENDING RELEASE)]
+ * Copyright (c) 1998-2015 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.)
 *
@@ -211,7 +211,7 @@ png_image_size(png_structrp png_ptr)

   if (png_ptr->rowbytes < 32768 && h < 32768)
   {
-      if (png_ptr->interlaced)
+      if (png_ptr->interlaced != 0)
      {
         /* Interlacing makes the image larger because of the replication of
          * both the filter byte and the padding to a byte boundary.
@@ -286,9 +286,7 @@ optimize_cmf(png_bytep data, png_alloc_size_t data_size)
      }
   }
 }
-#else
-#  define optimize_cmf(dp,dl) ((void)0)
-#endif /* PNG_WRITE_OPTIMIZE_CMF_SUPPORTED */
+#endif /* WRITE_OPTIMIZE_CMF */

 /* Initialize the compressor for the appropriate type of compression. */
 static int
@@ -297,7 +295,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
 {
   if (png_ptr->zowner != 0)
   {
-#     if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
+#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
      char msg[64];

      PNG_STRING_FROM_CHUNK(msg, owner);
@@ -309,8 +307,8 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
       * are minimal.
       */
      (void)png_safecat(msg, (sizeof msg), 10, " using zstream");
-#     endif
-#     if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
+#endif
+#if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC
         png_warning(png_ptr, msg);

         /* Attempt sane error recovery */
@@ -321,9 +319,9 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
         }

         png_ptr->zowner = 0;
-#     else
+#else
         png_error(png_ptr, msg);
-#     endif
+#endif
   }

   {
@@ -336,7 +334,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,

      if (owner == png_IDAT)
      {
-         if (png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY)
+         if ((png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY) != 0)
            strategy = png_ptr->zlib_strategy;

         else if (png_ptr->do_filter != PNG_FILTER_NONE)
@@ -348,20 +346,20 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,

      else
      {
-#        ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
+#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
            level = png_ptr->zlib_text_level;
            method = png_ptr->zlib_text_method;
            windowBits = png_ptr->zlib_text_window_bits;
            memLevel = png_ptr->zlib_text_mem_level;
            strategy = png_ptr->zlib_text_strategy;
-#        else
+#else
            /* If customization is not supported the values all come from the
             * IDAT values except for the strategy, which is fixed to the
             * default.  (This is the pre-1.6.0 behavior too, although it was
             * implemented in a very different way.)
             */
            strategy = Z_DEFAULT_STRATEGY;
-#        endif
+#endif
      }

      /* Adjust 'windowBits' down if larger than 'data_size'; to stop this
@@ -388,7 +386,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
      }

      /* Check against the previous initialized values, if any. */
-      if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) &&
+      if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0 &&
         (png_ptr->zlib_set_level != level ||
         png_ptr->zlib_set_method != method ||
         png_ptr->zlib_set_window_bits != windowBits ||
@@ -412,7 +410,7 @@ png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
      /* Now initialize if required, setting the new parameters, otherwise just
       * to a simple reset to the previous parameters.
       */
-      if (png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED)
+      if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
         ret = deflateReset(&png_ptr->zstream);

      else
@@ -619,9 +617,10 @@ png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
       */
      if (ret == Z_STREAM_END && input_len == 0)
      {
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
         /* Fix up the deflate header, if required */
         optimize_cmf(comp->output, comp->input_len);
-
+#endif
         /* But Z_OK is returned, not Z_STREAM_END; this allows the claim
          * function above to return Z_STREAM_END on an error (though it never
          * does in the current versions of zlib.)
@@ -664,7 +663,7 @@ png_write_compressed_data_out(png_structrp png_ptr, compression_state *comp)
   if (output_len > 0)
      png_error(png_ptr, "error writing ancillary chunked compressed data");
 }
-#endif /* PNG_WRITE_COMPRESSED_TEXT_SUPPORTED */
+#endif /* WRITE_COMPRESSED_TEXT */

 #if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
    defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
@@ -717,7 +716,7 @@ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)
         bad_character = ch; /* just skip it, record the first error */
   }

-   if (key_len > 0 && space) /* trailing space */
+   if (key_len > 0 && space != 0) /* trailing space */
   {
      --key_len, --new_key;
      if (bad_character == 0)
@@ -732,7 +731,7 @@ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key)

 #ifdef PNG_WARNINGS_SUPPORTED
   /* Try to only output one warning per keyword: */
-   if (*key) /* keyword too long */
+   if (*key != 0) /* keyword too long */
      png_warning(png_ptr, "keyword truncated");

   else if (bad_character != 0)
@@ -744,11 +743,11 @@ 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 /* PNG_WARNINGS_SUPPORTED */
+#endif /* WARNINGS */

   return key_len;
 }
-#endif
+#endif /* WRITE_TEXT || WRITE_pCAL || WRITE_iCCP || WRITE_sPLT */

 /* Write the IHDR chunk, and update the png_struct with the necessary
 * information.  Note that the rest of this code depends upon this
@@ -849,8 +848,8 @@ png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
    */
   if (
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-       !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
-       ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
+       !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
+       ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) &&
       (color_type == PNG_COLOR_TYPE_RGB ||
        color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
       (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
@@ -931,7 +930,7 @@ png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,

   if ((
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-       !(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) &&
+       (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 &&
 #endif
       num_pal == 0) || num_pal > 256)
   {
@@ -947,7 +946,7 @@ png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
      }
   }

-   if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
+   if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) == 0)
   {
      png_warning(png_ptr,
          "Ignoring request to write a PLTE chunk in grayscale PNG");
@@ -1074,11 +1073,11 @@ png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
         /* Write an IDAT containing the data then reset the buffer.  The
          * first IDAT may need deflate header optimization.
          */
-#        ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-            if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
-               png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
+            if ((png_ptr->mode & PNG_HAVE_IDAT) == 0 &&
+                png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
               optimize_cmf(data, png_image_size(png_ptr));
-#        endif
+#endif

         png_write_complete_chunk(png_ptr, png_IDAT, data, size);
         png_ptr->mode |= PNG_HAVE_IDAT;
@@ -1120,11 +1119,11 @@ png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
         png_bytep data = png_ptr->zbuffer_list->output;
         uInt size = png_ptr->zbuffer_size - png_ptr->zstream.avail_out;

-#        ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-            if (!(png_ptr->mode & PNG_HAVE_IDAT) &&
-               png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
-               optimize_cmf(data, png_image_size(png_ptr));
-#        endif
+#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
+         if ((png_ptr->mode & PNG_HAVE_IDAT) == 0 &&
+             png_ptr->compression_type == PNG_COMPRESSION_TYPE_BASE)
+            optimize_cmf(data, png_image_size(png_ptr));
+#endif

         png_write_complete_chunk(png_ptr, png_IDAT, data, size);
         png_ptr->zstream.avail_out = 0;
@@ -1345,7 +1344,7 @@ png_write_sBIT(png_structrp png_ptr, png_const_color_8p sbit, int color_type)
   png_debug(1, "in png_write_sBIT");

   /* Make sure we don't depend upon the order of PNG_COLOR_8 */
-   if (color_type & PNG_COLOR_MASK_COLOR)
+   if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
   {
      png_byte maxbits;

@@ -1378,7 +1377,7 @@ png_write_sBIT(png_structrp png_ptr, png_const_color_8p sbit, int color_type)
      size = 1;
   }

-   if (color_type & PNG_COLOR_MASK_ALPHA)
+   if ((color_type & PNG_COLOR_MASK_ALPHA) != 0)
   {
      if (sbit->alpha == 0 || sbit->alpha > png_ptr->usr_bit_depth)
      {
@@ -1465,9 +1464,9 @@ png_write_tRNS(png_structrp png_ptr, png_const_bytep trans_alpha,
      png_save_uint_16(buf + 2, tran->green);
      png_save_uint_16(buf + 4, tran->blue);
 #ifdef PNG_WRITE_16BIT_SUPPORTED
-      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]) != 0)
 #else
-      if (buf[0] | buf[2] | buf[4])
+      if ((buf[0] | buf[2] | buf[4]) != 0)
 #endif
      {
         png_app_warning(png_ptr,
@@ -1498,8 +1497,8 @@ png_write_bKGD(png_structrp png_ptr, png_const_color_16p back, int color_type)
   {
      if (
 #ifdef PNG_MNG_FEATURES_SUPPORTED
-          (png_ptr->num_palette ||
-          (!(png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE))) &&
+          (png_ptr->num_palette != 0 ||
+          (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0) &&
 #endif
         back->index >= png_ptr->num_palette)
      {
@@ -1511,15 +1510,15 @@ png_write_bKGD(png_structrp png_ptr, png_const_color_16p back, int color_type)
      png_write_complete_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
   }

-   else if (color_type & PNG_COLOR_MASK_COLOR)
+   else if ((color_type & PNG_COLOR_MASK_COLOR) != 0)
   {
      png_save_uint_16(buf, back->red);
      png_save_uint_16(buf + 2, back->green);
      png_save_uint_16(buf + 4, back->blue);
 #ifdef PNG_WRITE_16BIT_SUPPORTED
-      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]))
+      if (png_ptr->bit_depth == 8 && (buf[0] | buf[2] | buf[4]) != 0)
 #else
-      if (buf[0] | buf[2] | buf[4])
+      if ((buf[0] | buf[2] | buf[4]) != 0)
 #endif
      {
         png_warning(png_ptr,
@@ -1766,7 +1765,7 @@ png_write_iTXt(png_structrp png_ptr, int compression, png_const_charp key,
      png_write_compressed_data_out(png_ptr, &comp);

   else
-      png_write_chunk_data(png_ptr, (png_const_bytep)text, comp.input_len);
+      png_write_chunk_data(png_ptr, (png_const_bytep)text, comp.output_len);

   png_write_chunk_end(png_ptr);
 }
@@ -1986,12 +1985,13 @@ png_write_start_row(png_structrp png_ptr)
   }

   /* We only need to keep the previous row if we are using one of these. */
-   if (png_ptr->do_filter & (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH))
+   if ((png_ptr->do_filter &
+      (PNG_FILTER_AVG | PNG_FILTER_UP | PNG_FILTER_PAETH)) != 0)
   {
      /* Set up previous row buffer */
      png_ptr->prev_row = (png_bytep)png_calloc(png_ptr, buf_size);

-      if (png_ptr->do_filter & PNG_FILTER_UP)
+      if ((png_ptr->do_filter & PNG_FILTER_UP) != 0)
      {
         png_ptr->up_row = (png_bytep)png_malloc(png_ptr,
            png_ptr->rowbytes + 1);
@@ -1999,7 +1999,7 @@ png_write_start_row(png_structrp png_ptr)
         png_ptr->up_row[0] = PNG_FILTER_VALUE_UP;
      }

-      if (png_ptr->do_filter & PNG_FILTER_AVG)
+      if ((png_ptr->do_filter & PNG_FILTER_AVG) != 0)
      {
         png_ptr->avg_row = (png_bytep)png_malloc(png_ptr,
             png_ptr->rowbytes + 1);
@@ -2007,7 +2007,7 @@ png_write_start_row(png_structrp png_ptr)
         png_ptr->avg_row[0] = PNG_FILTER_VALUE_AVG;
      }

-      if (png_ptr->do_filter & PNG_FILTER_PAETH)
+      if ((png_ptr->do_filter & PNG_FILTER_PAETH) != 0)
      {
         png_ptr->paeth_row = (png_bytep)png_malloc(png_ptr,
             png_ptr->rowbytes + 1);
@@ -2015,13 +2015,13 @@ png_write_start_row(png_structrp png_ptr)
         png_ptr->paeth_row[0] = PNG_FILTER_VALUE_PAETH;
      }
   }
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */

 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
   /* If interlaced, we need to set up width and height of pass */
-   if (png_ptr->interlaced)
+   if (png_ptr->interlaced != 0)
   {
-      if (!(png_ptr->transformations & PNG_INTERLACE))
+      if ((png_ptr->transformations & PNG_INTERLACE) == 0)
      {
         png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
             png_pass_ystart[0]) / png_pass_yinc[0];
@@ -2076,10 +2076,10 @@ png_write_finish_row(png_structrp png_ptr)

 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
   /* If interlaced, go to next pass */
-   if (png_ptr->interlaced)
+   if (png_ptr->interlaced != 0)
   {
      png_ptr->row_number = 0;
-      if (png_ptr->transformations & PNG_INTERLACE)
+      if ((png_ptr->transformations & PNG_INTERLACE) != 0)
      {
         png_ptr->pass++;
      }
@@ -2104,7 +2104,7 @@ png_write_finish_row(png_structrp png_ptr)
                png_pass_ystart[png_ptr->pass]) /
                png_pass_yinc[png_ptr->pass];

-            if (png_ptr->transformations & PNG_INTERLACE)
+            if ((png_ptr->transformations & PNG_INTERLACE) != 0)
               break;

         } while (png_ptr->usr_width == 0 || png_ptr->num_rows == 0);
@@ -2314,7 +2314,7 @@ png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
 * been specified by the application, and then writes the row out with the
 * chosen filter.
 */
-static void
+static void /* PRIVATE */
 png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
   png_size_t row_bytes);

@@ -2383,7 +2383,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
   /* We don't need to test the 'no filter' case if this is the only filter
    * that has been chosen, as it doesn't actually do anything to the data.
    */
-   if ((filter_to_do & PNG_FILTER_NONE) && filter_to_do != PNG_FILTER_NONE)
+   if ((filter_to_do & PNG_FILTER_NONE) != 0 && filter_to_do != PNG_FILTER_NONE)
   {
      png_bytep rp;
      png_uint_32 sum = 0;
@@ -2459,7 +2459,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
      best_row = png_ptr->sub_row;
   }

-   else if (filter_to_do & PNG_FILTER_SUB)
+   else if ((filter_to_do & PNG_FILTER_SUB) != 0)
   {
      png_bytep rp, dp, lp;
      png_uint_32 sum = 0, lmins = mins;
@@ -2580,7 +2580,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
      best_row = png_ptr->up_row;
   }

-   else if (filter_to_do & PNG_FILTER_UP)
+   else if ((filter_to_do & PNG_FILTER_UP) != 0)
   {
      png_bytep rp, dp, pp;
      png_uint_32 sum = 0, lmins = mins;
@@ -2694,7 +2694,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
      best_row = png_ptr->avg_row;
   }

-   else if (filter_to_do & PNG_FILTER_AVG)
+   else if ((filter_to_do & PNG_FILTER_AVG) != 0)
   {
      png_bytep rp, dp, pp, lp;
      png_uint_32 sum = 0, lmins = mins;
@@ -2796,7 +2796,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
   }

   /* Paeth filter */
-   if (filter_to_do == PNG_FILTER_PAETH)
+   if ((filter_to_do == PNG_FILTER_PAETH) != 0)
   {
      png_bytep rp, dp, pp, cp, lp;
      png_size_t i;
@@ -2835,7 +2835,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
      best_row = png_ptr->paeth_row;
   }

-   else if (filter_to_do & PNG_FILTER_PAETH)
+   else if ((filter_to_do & PNG_FILTER_PAETH) != 0)
   {
      png_bytep rp, dp, pp, cp, lp;
      png_uint_32 sum = 0, lmins = mins;
@@ -2905,7 +2905,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
         pc = (p + pc) < 0 ? -(p + pc) : p + pc;
 #endif
         p = (pa <= pb && pa <=pc) ? a : (pb <= pc) ? b : c;
-#else /* PNG_SLOW_PAETH */
+#else /* SLOW_PAETH */
         p = a + b - c;
         pa = abs(p - a);
         pb = abs(p - b);
@@ -2919,7 +2919,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)

         else
            p = c;
-#endif /* PNG_SLOW_PAETH */
+#endif /* SLOW_PAETH */

         v = *dp++ = (png_byte)(((int)*rp++ - p) & 0xff);

@@ -2968,7 +2968,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
         best_row = png_ptr->paeth_row;
      }
   }
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */

   /* Do the actual writing of the filtered row data from the chosen filter. */
   png_write_filtered_row(png_ptr, best_row, row_info->rowbytes+1);
@@ -2988,7 +2988,7 @@ png_write_find_filter(png_structrp png_ptr, png_row_infop row_info)
      png_ptr->prev_filters[j] = best_row[0];
   }
 #endif
-#endif /* PNG_WRITE_FILTER_SUPPORTED */
+#endif /* WRITE_FILTER */
 }


@@ -3003,6 +3003,7 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,

   png_compress_IDAT(png_ptr, filtered_row, full_row_length, Z_NO_FLUSH);

+#ifdef PNG_WRITE_FILTER_SUPPORTED
   /* Swap the current and previous rows */
   if (png_ptr->prev_row != NULL)
   {
@@ -3012,6 +3013,7 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
      png_ptr->prev_row = png_ptr->row_buf;
      png_ptr->row_buf = tptr;
   }
+#endif /* WRITE_FILTER */

   /* Finish row - updates counters and flushes zlib if last row */
   png_write_finish_row(png_ptr);
@@ -3024,6 +3026,6 @@ png_write_filtered_row(png_structrp png_ptr, png_bytep filtered_row,
   {
      png_write_flush(png_ptr);
   }
-#endif
+#endif /* WRITE_FLUSH */
 }
-#endif /* PNG_WRITE_SUPPORTED */
+#endif /* WRITE */
--- a/projects/vstudio/readme.txt
+++ b/projects/vstudio/readme.txt
@@ -1,7 +1,7 @@

 VisualStudio instructions

-libpng version 1.6.15beta01 - October 29, 2014
+libpng version 1.6.17beta03 - February 17, 2015

 Copyright (c) 1998-2010 Glenn Randers-Pehrson

--- a/projects/vstudio/zlib.props
+++ b/projects/vstudio/zlib.props
@@ -2,7 +2,7 @@
 <!--
 * zlib.props - location of zlib source
 *
- * libpng version 1.6.15beta01 - October 29, 2014
+ * libpng version 1.6.17beta03 - February 17, 2015
 *
 * Copyright (c) 1998-2011 Glenn Randers-Pehrson
 *
--- a/scripts/README.txt
+++ b/scripts/README.txt
@@ -1,9 +1,9 @@

-Makefiles for  libpng version 1.6.15beta01 - October 29, 2014
+Makefiles for  libpng version 1.6.17beta03 - February 17, 2015

 pnglibconf.h.prebuilt       =>  Stores configuration settings
 makefile.linux    =>  Linux/ELF makefile
-                       (gcc, creates libpng16.so.16.1.6.15beta01)
+                       (gcc, creates libpng16.so.16.1.6.17beta03)
 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.16.1.6.15beta01)
+                       creates libpng16.so.16.1.6.17beta03)
 makefile.sgi      =>  Silicon Graphics IRIX makefile (cc, creates static lib)
 makefile.solaris  =>  Solaris 2.X makefile (gcc,
-                       creates libpng16.so.16.1.6.15beta01)
+                       creates libpng16.so.16.1.6.17beta03)
 makefile.so9      =>  Solaris 9 makefile (gcc,
-                       creates libpng16.so.16.1.6.15beta01)
+                       creates libpng16.so.16.1.6.17beta03)
 makefile.std      =>  Generic UNIX makefile (cc, creates static libpng.a)
 makefile.sunos    =>  Sun makefile
 makefile.32sunu   =>  Sun Ultra 32-bit makefile
--- a/scripts/def.dfn
+++ b/scripts/def.dfn
@@ -1,7 +1,7 @@
-/* def.dfn - define format of libpng.def
+/* def.c - define format of libpng.def
 *
- * Last changed in libpng version 1.5.7 [December 15, 2011]
- * Copyright (c) 2010-2011 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.6.16 [December 22, 2014]
+ * Copyright (c) 2011-2014 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
@@ -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 1.6.15beta01"
+PNG_DFN ";Version 1.6.17beta03"

 #define PNG_EXPORTA(ordinal, type, name, args, attributes)\
        PNG_DFN "@" SYMBOL_PREFIX "@@" name "@"
--- a/scripts/intprefix.dfn
+++ b/scripts/intprefix.dfn
@@ -1,8 +1,8 @@

-/* intprefix.dfn - generate an unprefixed internal symbol list
+/* intprefix.c - generate an unprefixed internal symbol list
 *
- * Last changed in libpng version 1.6.0 [January 30, 2012]
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.6.16 [December 22, 2014]
+ * Copyright (c) 2013-2014 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/scripts/libpng-config-head.in
+++ b/scripts/libpng-config-head.in
@@ -11,7 +11,7 @@

 # Modeled after libxml-config.

-version=1.6.15beta01
+version=1.6.17beta03
 prefix=""
 libdir=""
 libs=""
--- a/scripts/libpng.pc.in
+++ b/scripts/libpng.pc.in
@@ -5,6 +5,6 @@ includedir=@includedir@/libpng16

 Name: libpng
 Description: Loads and saves PNG files
-Version: 1.6.15beta01
+Version: 1.6.17beta03
 Libs: -L${libdir} -lpng16
 Cflags: -I${includedir}
--- a/scripts/makefile.bc32
+++ b/scripts/makefile.bc32
@@ -52,7 +52,9 @@ LDFLAGS=-L$(ZLIB_DIR) -M $(LDEBUG)

 # Pre-built configuration
 # See scripts\pnglibconf.mak for more options
+!ifndef PNGLIBCONF_H_PREBUILT
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
+!endif

 ## Variables
 OBJS = \
--- a/scripts/makefile.bor
+++ b/scripts/makefile.bor
@@ -60,7 +60,9 @@ LDFLAGS=-M -L$(ZLIB_DIR) $(MODEL_ARG) $(LDEBUG)

 # Pre-built configuration
 # See scripts\pnglibconf.mak for more options
+!ifndef PNGLIBCONF_H_PREBUILT
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
+!endif

 ## Variables

--- a/scripts/makefile.cegcc
+++ b/scripts/makefile.cegcc
@@ -23,7 +23,7 @@

 VERMAJ = 1
 VERMIN = 6
-VERMIC = 15
+VERMIC = 17
 VER = $(VERMAJ).$(VERMIN).$(VERMIC)
 NAME = libpng
 PACKAGE = $(NAME)-$(VER)
--- a/scripts/makefile.darwin
+++ b/scripts/makefile.darwin
@@ -36,12 +36,11 @@ LN_SF=ln -sf
 RANLIB=ranlib
 CP=cp
 RM_F=/bin/rm -f
-ARCH=-arch ppc -arch i386 -arch x86_64

 CPPFLAGS=-I$(ZLIBINC)
 # CFLAGS=-W -Wall -O3 -funroll-loops
-CFLAGS=-W -Wall -O -funroll-loops $(ARCH)
-LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz $(ARCH)
+CFLAGS=-W -Wall -O -funroll-loops
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng16 -lz

 INCPATH=$(prefix)/include
 LIBPATH=$(exec_prefix)/lib
@@ -113,7 +112,7 @@ $(LIBSOMAJ): $(OBJSDLL)
 	$(CC) -dynamiclib \
 	 -install_name $(LIBPATH)/$(LIBSOMAJ) \
 	 -current_version 16 -compatibility_version 16 \
-	 $(ARCH) -o $(LIBSOMAJ) \
+	 -o $(LIBSOMAJ) \
 	 $(OBJSDLL) -L$(ZLIBLIB) -lz

 pngtest: pngtest.o $(LIBSO)
--- a/scripts/makefile.linux
+++ b/scripts/makefile.linux
@@ -10,7 +10,7 @@
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
-RELEASE = 15
+RELEASE = 17

 # Shared library names:
 LIBSO=$(LIBNAME).so
--- a/scripts/makefile.msys
+++ b/scripts/makefile.msys
@@ -18,7 +18,7 @@ exec_prefix=$(prefix)
 # Library name:
 LIBNAME = libpng16
 PNGMAJ = 16
-RELEASE = 15
+RELEASE = 17

 # Shared library names:
 LIBSO=$(LIBNAME).dll
--- a/scripts/makefile.ne12bsd
+++ b/scripts/makefile.ne12bsd
@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include/libpng16

 LIB=	png16
 SHLIB_MAJOR=	0
-SHLIB_MINOR=	1.6.15beta01
+SHLIB_MINOR=	1.6.17beta03
 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
--- a/scripts/makefile.netbsd
+++ b/scripts/makefile.netbsd
@@ -17,7 +17,7 @@ INCSDIR=${LOCALBASE}/include

 LIB=	png
 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.15beta01
+SHLIB_MINOR=	1.6.17beta03
 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
--- a/scripts/makefile.openbsd
+++ b/scripts/makefile.openbsd
@@ -11,7 +11,7 @@ LIBDIR=	${PREFIX}/lib
 MANDIR= ${PREFIX}/man/cat

 SHLIB_MAJOR=	16
-SHLIB_MINOR=	1.6.15beta01
+SHLIB_MINOR=	1.6.17beta03

 LIB=	png
 SRCS=	png.c pngerror.c pngget.c pngmem.c pngpread.c \
--- a/scripts/makefile.tc3
+++ b/scripts/makefile.tc3
@@ -16,7 +16,9 @@ CP=copy

 # Pre-built configuration
 # See scripts\pnglibconf.mak for more options
+!ifndef PNGLIBCONF_H_PREBUILT
 PNGLIBCONF_H_PREBUILT = scripts\pnglibconf.h.prebuilt
+!endif

 O=.obj
 E=.exe
--- a/scripts/makefile.vcwin32
+++ b/scripts/makefile.vcwin32
@@ -16,7 +16,7 @@ CC = cl
 LD = link
 AR = lib
 CPPFLAGS = -I..\zlib
-CFLAGS  = -nologo -D_CRT_SECURE_NO_DEPRECATE -MD -O2 -W3
+CFLAGS  = -nologo -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS -MD -O2 -W3
 LDFLAGS = -nologo
 ARFLAGS = -nologo
 CP = copy
--- a/scripts/pnglibconf.dfa
+++ b/scripts/pnglibconf.dfa
@@ -221,7 +221,7 @@ option SET_OPTION disabled
 # ARM_NEON_API:   (PNG_ARM_NEON == 1) allow the optimization to be switched on
 #                 with png_set_option
 # ARM_NEON_CHECK: (PNG_ARM_NEON == 1) compile a run-time check to see if Neon
-#                 extensions are supported, this is poorly supported and
+#                 extensions are supported. This is poorly supported and
 #                 deprectated - use the png_set_option API.
 setting ARM_NEON_OPT
 option ARM_NEON_API disabled requires ALIGNED_MEMORY enables SET_OPTION,
@@ -303,7 +303,7 @@ option BENIGN_READ_ERRORS requires BENIGN_ERRORS
 option MNG_FEATURES

 # Arithmetic options, the first is the big switch that chooses between internal
-# floating and fixed point arithmetic implementations - it does not affect an
+# floating and fixed point arithmetic implementations - it does not affect any
 # APIs.  The second two (the _POINT settings) switch off individual APIs.
 #
 # Prior to libpng 1.6.8 one of the API (_POINT) variants had to be selected.  At
@@ -350,36 +350,15 @@ option USER_MEM

 option IO_STATE

-# This is only for PowerPC big-endian and 680x0 systems
-# some testing, not enabled by default.
-# NO LONGER USED
-
-#option READ_BIG_ENDIAN disabled
-
-# Allow users to control limits on what the READ code will
-# read:
-
-# Added at libpng-1.2.43; adds limit fields to png_struct,
-# allows some usages of these fields
-
-option USER_LIMITS
-
-# Added at libpng-1.2.6; adds setting APIs, allows additional
-# usage of this field (UTSL)
-
-option SET_USER_LIMITS requires USER_LIMITS
-
-# Feature added at libpng-1.4.0, this flag added at 1.4.1
-option SET_USER_LIMITS enables SET_CHUNK_CACHE_LIMIT
-# Feature added at libpng-1.4.1, this flag added at 1.4.1
-
-option SET_USER_LIMITS enables SET_CHUNK_MALLOC_LIMIT
-
-# Libpng limits.
+# Libpng limits: limit the size of images and data on read.
 #
-# If these settings are *not* set libpng will not limit the size of
-# images or the size of data in ancilliary chunks.  This does lead to
-# security issues if PNG files come from untrusted sources.  Settings have the
+# If this option is disabled all the limit checking code will be disabled:
+
+option USER_LIMITS requires READ
+
+# The default settings given below for the limits mean that libpng will
+# limit the size of images or the size of data in ancilliary chunks to less
+# than the specification or implementation limits. Settings have the
 # following interpretations:
 #
 # USER_WIDTH_MAX: maximum width of an image that will be read
@@ -389,17 +368,14 @@ option SET_USER_LIMITS enables SET_CHUNK_MALLOC_LIMIT
 #
 # Only chunks that are variable in number are counted towards the
 # USER_CHUNK_CACHE_MAX limit
-setting USER_WIDTH_MAX
-setting USER_HEIGHT_MAX
-setting USER_CHUNK_CACHE_MAX
-setting USER_CHUNK_MALLOC_MAX
+setting USER_WIDTH_MAX default        1000000 /* Use 0x7fffffff for unlimited */
+setting USER_HEIGHT_MAX default       1000000 /* Use 0x7fffffff for unlimited */
+setting USER_CHUNK_CACHE_MAX default     1000 /* Use 0 for unlimited */
+setting USER_CHUNK_MALLOC_MAX default 8000000 /* Use 0 for unlimited */

-# To default all these settings to values that are large but probably
-# safe turn the SAFE_LIMITS option on; this will cause the value in
-# pngpriv.h to be used.  Individual values can also be set, simply set
-# them in pngusr.dfa with '@#define PNG_setting value' lines.
-option SAFE_LIMITS enables USER_LIMITS disabled
-= SAFE_LIMITS SAFE_LIMITS
+# If this option is enabled APIs to set the above limits at run time are added;
+# without this the hardwired (compile time) limits will be used.
+option SET_USER_LIMITS requires USER_LIMITS

 # All of the following options relate to code capabilities for
 # processing image data before creating a PNG or after reading one.
@@ -541,6 +517,7 @@ option USER_TRANSFORM_INFO if READ_USER_TRANSFORM, WRITE_USER_TRANSFORM
 # non-IDAT chunks (zTXt, iTXt, iCCP, and unknown chunks).  This feature
 # was added at libpng-1.5.3.
 option WRITE_CUSTOMIZE_ZTXT_COMPRESSION requires WRITE
+option WRITE_CUSTOMIZE_COMPRESSION requires WRITE

 # Any chunks you are not interested in, you can undef here.  The
 # ones that allocate memory may be expecially important (hIST,
--- a/scripts/pnglibconf.h.prebuilt
+++ b/scripts/pnglibconf.h.prebuilt
@@ -1,8 +1,8 @@
-/* libpng 1.6.15beta01 STANDARD API DEFINITION */
+/* libpng 1.6.17beta03 STANDARD API DEFINITION */

 /* pnglibconf.h - library build configuration */

-/* Libpng version 1.6.15beta01 - October 29, 2014 */
+/* Libpng version 1.6.17beta03 - February 17, 2015 */

 /* Copyright (c) 1998-2014 Glenn Randers-Pehrson */

@@ -97,7 +97,6 @@
 #define PNG_READ_tIME_SUPPORTED
 #define PNG_READ_tRNS_SUPPORTED
 #define PNG_READ_zTXt_SUPPORTED
-/*#undef PNG_SAFE_LIMITS_SUPPORTED*/
 #define PNG_SAVE_INT_32_SUPPORTED
 #define PNG_SAVE_UNKNOWN_CHUNKS_SUPPORTED
 #define PNG_SEQUENTIAL_READ_SUPPORTED
@@ -129,6 +128,7 @@
 #define PNG_WRITE_BGR_SUPPORTED
 #define PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED
 #define PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
+#define PNG_WRITE_CUSTOMIZE_COMPRESSION_SUPPORTED
 #define PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
 #define PNG_WRITE_FILLER_SUPPORTED
 #define PNG_WRITE_FILTER_SUPPORTED
@@ -198,6 +198,10 @@
 #define PNG_QUANTIZE_RED_BITS 5
 #define PNG_TEXT_Z_DEFAULT_COMPRESSION (-1)
 #define PNG_TEXT_Z_DEFAULT_STRATEGY 0
+#define PNG_USER_CHUNK_CACHE_MAX 1000 /* Use 0 for unlimited */
+#define PNG_USER_CHUNK_MALLOC_MAX 8000000 /* Use 0 for unlimited */
+#define PNG_USER_HEIGHT_MAX 1000000 /* Use 0x7fffffff for unlimited */
+#define PNG_USER_WIDTH_MAX 1000000 /* Use 0x7fffffff for unlimited */
 #define PNG_WEIGHT_SHIFT 8
 #define PNG_ZBUF_SIZE 8192
 #define PNG_ZLIB_VERNUM 0 /* unknown */
--- a/scripts/prefix.dfn
+++ b/scripts/prefix.dfn
@@ -1,8 +1,8 @@

-/* prefix.dfn - generate an unprefixed symbol list
+/* prefix.c - generate an unprefixed symbol list
 *
- * Last changed in libpng version 1.6.0 [January 30, 2012]
- * Copyright (c) 2012 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.6.16 [December 22, 2014]
+ * Copyright (c) 2013-2014 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/scripts/sym.dfn
+++ b/scripts/sym.dfn
@@ -1,8 +1,8 @@

-/* sym.dfn - define format of libpng.sym
+/* sym.c - define format of libpng.sym
 *
- * Last changed in libpng version 1.5.0 [January 6, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.6.16 [December 22, 2014]
+ * Copyright (c) 2011-2014 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/scripts/symbols.dfn
+++ b/scripts/symbols.dfn
@@ -1,8 +1,8 @@

-/* symbols.dfn - find all exported symbols
+/* symbols.c - find all exported symbols
 *
- * Last changed in libpng version 1.5.0 [January 6, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.6.16 [December 22, 2014]
+ * Copyright (c) 2011-2014 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
--- a/scripts/symbols.def
+++ b/scripts/symbols.def
@@ -1,4 +1,4 @@
-;Version 1.6.15beta01
+;Version 1.6.17beta03
 ;--------------------------------------------------------------
 ; LIBPNG symbol list as a Win32 DEF file
 ; Contains all the symbols that can be exported from libpng
--- a/scripts/vers.dfn
+++ b/scripts/vers.dfn
@@ -1,8 +1,8 @@

-/* vers.dfn - define format of libpng.vers
+/* vers.c - define format of libpng.vers
 *
- * Last changed in libpng version 1.5.0 [January 6, 2011]
- * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * Last changed in libpng version 1.6.16 [December 22, 2014]
+ * Copyright (c) 2011-2014 Glenn Randers-Pehrson
 *
 * This code is released under the libpng license.
 * For conditions of distribution and use, see the disclaimer
Author	SHA1	Message	Date
Glenn Randers-Pehrson	de23a49231	[libpng16] Imported from libpng-1.6.17beta03.tar	2015-02-17 10:52:21 -06:00
Glenn Randers-Pehrson	4b65a89cf4	[libpng16] Eliminated PNG_SAFE_LIMITS macro and restored the 1-million-column and 1-million-row default limits in pnglibconf.dfa, that can be reset by the user at build time or run time. This provides a more robust defense against DOS and as-yet undiscovered overflows. Display user limits in the output from pngtest.	2015-02-16 22:52:07 -06:00
Glenn Randers-Pehrson	471b38aa00	[libpng16] Bump version to 1.6.17beta03	2015-02-07 09:16:17 -06:00
Glenn Randers-Pehrson	b6c9ac6304	[libpng16] Imported from libpng-1.6.17beta02.tar	2015-02-07 09:07:09 -06:00
Glenn Randers-Pehrson	8cd78da8b3	[libpng16] Do not build png_product2() when it is unused. Work around more Coverity-scan dead-code warnings.	2015-02-07 09:03:30 -06:00
Glenn Randers-Pehrson	8f0e2729dd	[libpng16] Improved comments on some #ifdef lines.	2015-02-03 19:10:03 -06:00
Glenn Randers-Pehrson	c73d6219f2	[libpng16] Bump version to 1.6.17beta02	2015-01-28 19:20:51 -06:00
Glenn Randers-Pehrson	6ef579df50	[libpng16] Imported from libpng-1.6.17beta01.tar	2015-01-28 19:15:16 -06:00
Glenn Randers-Pehrson	bd76965879	[libpng16] Added #ifndef __COVERITY__ where needed in png.c, pngrutil.c and pngset.c to avoid warnings about dead code.	2015-01-27 06:53:56 -06:00
Glenn Randers-Pehrson	7a015b92b2	[libpng16] Update "last changed" comment in pngset.c	2015-01-13 09:41:25 -06:00
Glenn Randers-Pehrson	2f56fe4071	[libpng16] Made the check for out-of-range values in png_set_tRNS() detect values that are exactly 2^bit_depth, and work on 16-bit platforms.	2015-01-13 09:25:48 -06:00
Glenn Randers-Pehrson	9d6cab3b21	[libpng16] Updated recent CVE numbers in CHANGES file.	2015-01-10 19:18:17 -06:00
Glenn Randers-Pehrson	04affde6a1	[libpng16] Happy 2015, continued.	2014-12-31 19:03:08 -06:00
Glenn Randers-Pehrson	018b4fccb9	[libpng16] Happy New Year! Update copyright year.	2014-12-31 18:45:23 -06:00
Glenn Randers-Pehrson	bba3aa9533	[libpng16] Update "last changed" info in pngrtran.c	2014-12-29 16:36:50 -06:00
John Bowler	b6788ccaff	[libpng16] Implement previously untested libpng transforms in pngvalid.c	2014-12-29 16:31:58 -06:00
John Bowler	cde8cd6b30	[libpng16] Fixed byte order in 2-byte filler, in png_do_read_filler().	2014-12-29 16:24:33 -06:00
John Bowler	19ec55f40e	[libpng16] Added testing of png_set_packing() to pngvalid.c	2014-12-27 19:10:04 -06:00
John Bowler	6a6eb354ff	[libpng16] Removed user limits from pngfix. Also pass NULL pointers to png_read_row to skip the unnecessary row de-interlace stuff.	2014-12-24 18:54:08 -06:00
Glenn Randers-Pehrson	6b5abbe58e	[libpng16] Corrected the width limit calculation in png_check_IHDR().	2014-12-23 14:33:02 -06:00
Glenn Randers-Pehrson	66c1ec5a26	[libpng16] Removed duplicate PNG_SAFE_LIMITS_SUPPORTED handling from pngconf.h	2014-12-23 14:18:36 -06:00
Glenn Randers-Pehrson	ecd074945c	[libpng16] Bump version to 1.6.17beta01	2014-12-21 22:56:42 -06:00
Glenn Randers-Pehrson	88dd30b232	[libpng16] Imported from libpng-1.6.16.tar	2014-12-21 21:53:00 -06:00
Glenn Randers-Pehrson	10569a452f	[libpng16] Imported from libpng-1.6.16rc03.tar	2014-12-21 17:12:39 -06:00
John Bowler	dc294204b6	[libpng16] Fixed an overflow in png_combine_row with very wide interlaced images.	2014-12-21 17:11:33 -06:00
Glenn Randers-Pehrson	06ee38423b	[libpng16] Imported from libpng-1.6.16rc02.tar	2014-12-21 13:54:45 -06:00
Glenn Randers-Pehrson	6d8c88177a	[libpng16] Imported from libpng-1.6.16rc01.tar	2014-12-21 09:18:15 -06:00
Glenn Randers-Pehrson	f43b5e3709	[libpng16] Imported from libpng-1.6.16beta03.tar	2014-12-20 19:21:32 -06:00
John Bowler	a00ea0aeae	[libpng16] Quiet a "comparison always true" warning in pngstest.c (John Bowler).	2014-12-16 19:18:06 -06:00
Glenn Randers-Pehrson	0659cddd21	[libpng16] Bump version to 1.6.16beta03	2014-12-14 19:42:05 -06:00
Glenn Randers-Pehrson	66d846b0cc	[libpng16] Imported from libpng-1.6.16beta02.tar	2014-12-14 19:24:00 -06:00
John Bowler	d040886dc4	[libpng16] Revised handling of scripts/.dfn; renamed them to scripts/.c	2014-12-14 19:17:56 -06:00
Glenn Randers-Pehrson	91f9e0370d	[libpng16] Bump version to 1.6.16beta02	2014-12-14 12:43:12 -06:00
Glenn Randers-Pehrson	86a7eef997	[libpng16] Imported from libpng-1.6.16beta01.tar	2014-12-14 12:38:35 -06:00
Bob Friesenhahn	530eec311d	[libpng16] Revised Makefile.am and scripts/symbols.dfn to work with MinGW/MSYS	2014-12-14 12:37:12 -06:00
Glenn Randers-Pehrson	7c5d037032	[libpng16] Update arm/*.c to libpng coding style.	2014-11-29 17:04:35 -06:00
Glenn Randers-Pehrson	ee16fc4a6f	[libpng16] Added ".align 2" to arm/filter_neon.S to support old GAS assemblers that don't do alignment correctly.	2014-11-29 16:27:27 -06:00
Glenn Randers-Pehrson	2d24cbdd98	[libpng16] Bump version to 1.6.16beta01	2014-11-21 08:25:32 -06:00
Glenn Randers-Pehrson	e8ef689cb9	[libpng16] Imported from libpng-1.6.15.tar	2014-11-20 10:22:57 -06:00
Glenn Randers-Pehrson	aebb7585c9	[libpng16] Imported from libpng-1.6.15rc03.tar	2014-11-16 20:04:53 -06:00
Cosmin Truta	5b9ac20297	[libpng16] Added "-D_CRT_SECURE_NO_WARNINGS" to CFLAGS in scripts/makefile.vcwin32. Removed the obsolete $ARCH variable from scripts/makefile.darwin.	2014-11-16 19:37:42 -06:00
Glenn Randers-Pehrson	9c05216461	[libpng16] Fix typos in ANNOUNCE and CHANGES	2014-11-14 17:59:40 -06:00
Glenn Randers-Pehrson	d4965b4014	[libpng16] Imported from libpng-1.6.15rc02.tar	2014-11-14 09:51:59 -06:00
Cosmin Truta	b8eb945946	[libpng16] The macros passed in the command line to Borland make were ignored if similarly-named macros were already defined in makefiles. This behavior is different from POSIX make and other make programs. Surround the macro definitions with ifndef guards (Cosmin).	2014-11-14 09:47:54 -06:00
Glenn Randers-Pehrson	6df21524cd	[libpng16] Imported from libpng-1.6.15rc01.tar	2014-11-13 06:47:08 -06:00
Glenn Randers-Pehrson	fa49aae286	[libpng16] Imported from libpng-1.6.15beta08.tar	2014-11-08 09:08:03 -06:00
Glenn Randers-Pehrson	05e11008c0	[libpng16] More "#endif" housecleaning, in *.h	2014-11-07 07:41:16 -06:00
Glenn Randers-Pehrson	40656e9855	[libpng16] Bump version to 1.6.15beta08	2014-11-07 06:45:39 -06:00
Glenn Randers-Pehrson	7cee075a32	[libpng16] Imported from libpng-1.6.15beta07.tar	2014-11-07 06:40:30 -06:00
Glenn Randers-Pehrson	985dc00f1f	[libpng16] Fix typo in example.c	2014-11-06 23:17:35 -06:00
Glenn Randers-Pehrson	cda68df8c1	[libpng16] Changed "#endif /* PNG_FEATURE_SUPPORTED /" to "#endif / FEATURE */"	2014-11-06 22:11:39 -06:00
Glenn Randers-Pehrson	70cb8f9a7e	[libpng16] Removed #ifdef PNG_16BIT_SUPPORTED/#endif around png_product2(); it is needed by png_reciprocal2(). Added #ifdef PNG_16BIT_SUPPORTED/#endif around png_log16bit() and png_do_swap().	2014-11-06 20:58:33 -06:00
Glenn Randers-Pehrson	674c3e5816	[libpng16] Bump version to 1.6.15beta07	2014-11-06 07:37:32 -06:00
Glenn Randers-Pehrson	61ea3eacb0	[libpng16] Reverted use png_get_libpng_ver(NULL) instead of PNG_LIBPNG_VER_STRING in the manual, example.c, pngtest.c, and applications in the contrib directory. It was incorrect advice.	2014-11-06 06:39:56 -06:00
Glenn Randers-Pehrson	8e7c35fc81	[libpng16] Bump version to 1.6.15beta06	2014-11-05 19:08:08 -06:00
Glenn Randers-Pehrson	234fe626af	[libpng16] Imported from libpng-1.6.15beta05.tar	2014-11-05 19:07:58 -06:00
John Bowler	03df189954	[libpng16] Fixed array size calculations to avoid warnings. At various points in the code the number of elements in an array is calculated using sizeof. This generates a compile time constant of type (size_t) which is then typically assigned to an (unsigned int) or (int). Some versions of GCC on 64-bit systems warn about the apparent narrowing, even though the same compiler does apparently generate the correct, in-range, numeric constant. This adds appropriate, safe, casts to make the warnings go away.	2014-11-05 17:19:36 -06:00
John Bowler	6f2c50e7fc	[libpng16] Free all allocated memory in pngimage. The file buffer cache was left allocated at the end of the program, harmless but it causes memory leak reports from clang.	2014-11-05 17:11:59 -06:00
John Bowler	c9720568d0	[libpng16] Fixed GCC unsigned int->float warnings. Various versions of GCC seem to generate warnings when an unsigned value is implicitly converted to double. This is probably a GCC bug but this change avoids the issue by explicitly converting to (int) where safe.	2014-11-05 17:06:27 -06:00
Glenn Randers-Pehrson	5be76ae252	[libpng16] use PNG_LIBPNG_VER_STRING[i] in png_user_version_check()	2014-11-05 15:02:45 -06:00
Glenn Randers-Pehrson	a2fe24d186	[libpng16] Simplified and future-proofed png_user_version_check().	2014-11-05 12:00:32 -06:00
Glenn Randers-Pehrson	97dd654ba4	[libpng16] Avoid out-of-bounds memory access in png_user_version_check().	2014-11-05 09:22:19 -06:00
Glenn Randers-Pehrson	f1b547a509	[libpng16] Use png_get_libpng_ver(NULL), not PNG_LIBPNG_VER_STRING	2014-11-04 23:33:46 -06:00
Glenn Randers-Pehrson	5efb1327df	[libpng16] Bump version to 1.6.15beta05	2014-11-04 07:08:37 -06:00
Glenn Randers-Pehrson	b5113f4e70	[libpng16] Imported from libpng-1.6.15beta04.tar	2014-11-04 07:08:23 -06:00
John Bowler	445475a166	[libpng16] Removed new PNG_USE_ARM_NEON configuration flag and made a one-line revision to configure.ac to support ARM on aarch64 instead (John Bowler).	2014-11-03 19:44:39 -06:00
Glenn Randers-Pehrson	2eb712e519	[libpng16] Bump version to 1.6.15beta04	2014-11-03 09:33:51 -06:00
Glenn Randers-Pehrson	736c8e8773	[libpng16] Imported from libpng-1.6.15beta03.tar	2014-11-03 09:33:44 -06:00
Glenn Randers-Pehrson	3278452323	[libpng16] Added PNG_USE_ARM_NEON configuration flag (Marcin Juszkiewicz).	2014-11-03 08:24:34 -06:00
Glenn Randers-Pehrson	bd3818eb1b	[libpng16] Bump version to 1.6.15beta03	2014-11-01 18:59:15 -05:00
Glenn Randers-Pehrson	b75c3cc415	[libpng16] Imported from libpng-1.6.15beta02.tar	2014-11-01 18:59:08 -05:00
Glenn Randers-Pehrson	b963feeec6	[libpng16] More cosmetic changes	2014-11-01 13:18:36 -05:00
Glenn Randers-Pehrson	f2d4167fee	[libpng16] Added a pair of parentheses suggested by clang	2014-10-31 21:17:11 -05:00
Glenn Randers-Pehrson	5d713fe123	[libpng16] Changed remaining "if (!x)" to "if (x == 0)" and "if (x)" to "if (x !== 0)"	2014-10-31 20:58:40 -05:00
Glenn Randers-Pehrson	6b9a20e7f9	[libpng16] Bump version to 1.6.15beta02	2014-10-29 09:13:06 -05:00