ANNOUNCE - third_party/libpng - Git at Google

 Libpng 1.6.19beta04 - October 15, 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.

 Files available for download:

 Source files with LF line endings (for Unix/Linux) and with a
 "configure" script

    1.6.19beta04.tar.xz (LZMA-compressed, recommended)
    1.6.19beta04.tar.gz

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

    lp1619b04.7z  (LZMA-compressed, recommended)
    lp1619b04.zip

 Other information:

    1.6.19beta04-README.txt
    1.6.19beta04-LICENSE.txt
    libpng-1.6.19beta04-*.asc (armored detached GPG signatures)

 Changes since the last public release (1.6.18):

 Version 1.6.19beta01 [July 30, 2015]

   Updated obsolete information about the simplified API macros in the
     manual pages (Bug report by Arc Riley).
   Avoid potentially dereferencing NULL info_ptr in png_info_init_3().
   Rearranged png.h to put the major sections in the same order as
     in libpng17.
   Eliminated unused PNG_COST_SHIFT, PNG_WEIGHT_SHIFT, PNG_COST_FACTOR, and
     PNG_WEIGHT_FACTOR macros.
   Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
     (Bug report by Viktor Szakats).  Several warnings remain and are
     unavoidable, where we test for overflow.
   Fixed potential leak of png_pixels in contrib/pngminus/pnm2png.c
   Fixed uninitialized variable in contrib/gregbook/rpng2-x.c

 Version 1.6.19beta02 [August 19, 2015]
   Moved config.h.in~ from the "libpng_autotools_files" list to the
     "libpng_autotools_extra" list in autogen.sh because it was causing a
     false positive for missing files (bug report by Robert C. Seacord).
   Removed unreachable "break" statements in png.c, pngread.c, and pngrtran.c
     to suppress clang warnings (Bug report by Viktor Szakats).
   Fixed some bad links in the man page.
   Changed "n bit" to "n-bit" in comments.
   Added signed/unsigned 16-bit safety net. This removes the dubious
     0x8000 flag definitions on 16-bit systems. They aren't supported
     yet the defs *probably* work, however it seems much safer to do this
     and be advised if anyone, contrary to advice, is building libpng 1.6
     on a 16-bit system. It also adds back various switch default clauses
     for GCC; GCC errors out if they are not present (with an appropriately
     high level of warnings).
   Safely convert num_bytes to a png_byte in png_set_sig_bytes() (Robert
     Seacord).
   Fixed the recently reported 1's complement security issue by replacing
     the value that is illegal in the PNG spec, in both signed and unsigned
     values, with 0. Illegal unsigned values (anything greater than or equal
     to  0x80000000) can still pass through, but since these are not illegal
     in ANSI-C (unlike 0x80000000 in the signed case) the checking that
     occurs later can catch them (John Bowler).

 Version 1.6.19beta03 [September 26, 2015]
   Fixed png_save_int_32 when int is not 2's complement (John Bowler).
   Updated libpng16 with all the recent test changes from libpng17,
     including changes to pngvalid.c to ensure that the original,
     distributed, version of contrib/visupng/cexcept.h can be used
     (John Bowler).
   pngvalid contains the correction to the use of SAVE/STORE_
     UNKNOWN_CHUNKS; a bug revealed by changes in libpng 1.7. More
     tests contain the --strict option to detect warnings and the
     pngvalid-standard test has been corrected so that it does not
     turn on progressive-read. There is a separate test which does
     that. (John Bowler)
   Also made some signed/unsigned fixes.
   Make pngstest error limits version specific. Splitting the machine
     generated error structs out to a file allows the values to be updated
     without changing pngstest.c itself. Since libpng 1.6 and 1.7 have
     slightly different error limits this simplifies maintenance. The
     makepngs.sh script has also been updated to more accurately reflect
     current problems in libpng 1.7 (John Bowler).
   Incorporated new test PNG files into make check.  tests/pngstest-*
     are changed so that the new test files are divided into 8 groups by
     gamma and alpha channel.  These tests have considerably better code
     and pixel-value coverage than contrib/pngsuite; however,coverage is
     still incomplete (John Bowler).
   Removed the '--strict' in 1.6 because of the double-gamma-correction
     warning, updated pngstest-errors.h for the errors detected with the
     new contrib/testspngs PNG test files (John Bowler).

 Version 1.6.19beta04 [October 15, 2015]
   Worked around rgb-to-gray issues in libpng 1.6.  The previous
     attempts to ignore the errors in the code aren't quite enough to
     deal with the 'channel selection' encoding added to libpng 1.7; abort.
   Fixed 'pow' macros in pngvalid.c. It is legal for 'pow' to be a
     macro, therefore the argument list cannot contain preprocessing
     directives.  Make sure pow is a function where this happens. This is
     a minimal safe fix, the issue only arises in non-performance-critical
     code (bug report by Curtis Leach, fix by John Bowler).
   Added sPLT support to pngtest.c

 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
 https://lists.sourceforge.net/lists/listinfo/png-mng-implement
 to subscribe)
 or to glennrp at users.sourceforge.net

 Glenn R-P
	Libpng 1.6.19beta04 - October 15, 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.

	Files available for download:

	Source files with LF line endings (for Unix/Linux) and with a
	"configure" script

	1.6.19beta04.tar.xz (LZMA-compressed, recommended)
	1.6.19beta04.tar.gz

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

	lp1619b04.7z (LZMA-compressed, recommended)
	lp1619b04.zip

	Other information:

	1.6.19beta04-README.txt
	1.6.19beta04-LICENSE.txt
	libpng-1.6.19beta04-*.asc (armored detached GPG signatures)

	Changes since the last public release (1.6.18):

	Version 1.6.19beta01 [July 30, 2015]

	Updated obsolete information about the simplified API macros in the
	manual pages (Bug report by Arc Riley).
	Avoid potentially dereferencing NULL info_ptr in png_info_init_3().
	Rearranged png.h to put the major sections in the same order as
	in libpng17.
	Eliminated unused PNG_COST_SHIFT, PNG_WEIGHT_SHIFT, PNG_COST_FACTOR, and
	PNG_WEIGHT_FACTOR macros.
	Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
	(Bug report by Viktor Szakats). Several warnings remain and are
	unavoidable, where we test for overflow.
	Fixed potential leak of png_pixels in contrib/pngminus/pnm2png.c
	Fixed uninitialized variable in contrib/gregbook/rpng2-x.c

	Version 1.6.19beta02 [August 19, 2015]
	Moved config.h.in~ from the "libpng_autotools_files" list to the
	"libpng_autotools_extra" list in autogen.sh because it was causing a
	false positive for missing files (bug report by Robert C. Seacord).
	Removed unreachable "break" statements in png.c, pngread.c, and pngrtran.c
	to suppress clang warnings (Bug report by Viktor Szakats).
	Fixed some bad links in the man page.
	Changed "n bit" to "n-bit" in comments.
	Added signed/unsigned 16-bit safety net. This removes the dubious
	0x8000 flag definitions on 16-bit systems. They aren't supported
	yet the defs probably work, however it seems much safer to do this
	and be advised if anyone, contrary to advice, is building libpng 1.6
	on a 16-bit system. It also adds back various switch default clauses
	for GCC; GCC errors out if they are not present (with an appropriately
	high level of warnings).
	Safely convert num_bytes to a png_byte in png_set_sig_bytes() (Robert
	Seacord).
	Fixed the recently reported 1's complement security issue by replacing
	the value that is illegal in the PNG spec, in both signed and unsigned
	values, with 0. Illegal unsigned values (anything greater than or equal
	to 0x80000000) can still pass through, but since these are not illegal
	in ANSI-C (unlike 0x80000000 in the signed case) the checking that
	occurs later can catch them (John Bowler).

	Version 1.6.19beta03 [September 26, 2015]
	Fixed png_save_int_32 when int is not 2's complement (John Bowler).
	Updated libpng16 with all the recent test changes from libpng17,
	including changes to pngvalid.c to ensure that the original,
	distributed, version of contrib/visupng/cexcept.h can be used
	(John Bowler).
	pngvalid contains the correction to the use of SAVE/STORE_
	UNKNOWN_CHUNKS; a bug revealed by changes in libpng 1.7. More
	tests contain the --strict option to detect warnings and the
	pngvalid-standard test has been corrected so that it does not
	turn on progressive-read. There is a separate test which does
	that. (John Bowler)
	Also made some signed/unsigned fixes.
	Make pngstest error limits version specific. Splitting the machine
	generated error structs out to a file allows the values to be updated
	without changing pngstest.c itself. Since libpng 1.6 and 1.7 have
	slightly different error limits this simplifies maintenance. The
	makepngs.sh script has also been updated to more accurately reflect
	current problems in libpng 1.7 (John Bowler).
	Incorporated new test PNG files into make check. tests/pngstest-*
	are changed so that the new test files are divided into 8 groups by
	gamma and alpha channel. These tests have considerably better code
	and pixel-value coverage than contrib/pngsuite; however,coverage is
	still incomplete (John Bowler).
	Removed the '--strict' in 1.6 because of the double-gamma-correction
	warning, updated pngstest-errors.h for the errors detected with the
	new contrib/testspngs PNG test files (John Bowler).

	Version 1.6.19beta04 [October 15, 2015]
	Worked around rgb-to-gray issues in libpng 1.6. The previous
	attempts to ignore the errors in the code aren't quite enough to
	deal with the 'channel selection' encoding added to libpng 1.7; abort.
	Fixed 'pow' macros in pngvalid.c. It is legal for 'pow' to be a
	macro, therefore the argument list cannot contain preprocessing
	directives. Make sure pow is a function where this happens. This is
	a minimal safe fix, the issue only arises in non-performance-critical
	code (bug report by Curtis Leach, fix by John Bowler).
	Added sPLT support to pngtest.c

	Send comments/corrections/commendations to png-mng-implement at lists.sf.net
	(subscription required; visit
	https://lists.sourceforge.net/lists/listinfo/png-mng-implement
	to subscribe)
	or to glennrp at users.sourceforge.net

	Glenn R-P