libpng: update to 1.2.43

third_party/libpng/README

-README for libpng version 1.2.37 - June 4, 2009 (shared library 12.0)
+README for libpng version 1.2.43 - February 25, 2010 (shared library 12.0)
 See the note about version numbers near the top of png.h
 
 See INSTALL for instructions on how to install libpng.
 
 Libpng comes in several distribution formats.  Get libpng-*.tar.gz,
-libpng-*.tar.lzma, or libpng-*.tar.bz2 if you want UNIX-style line
+libpng-*.tar.xz, or libpng-*.tar.bz2 if you want UNIX-style line
 endings in the text files, or lpng*.7z or lpng*.zip if you want DOS-style
 line endings.  You can get UNIX-style line endings from the *.zip file
 by using "unzip -a" but there seems to be no simple way to recover
-UNIX-style line endings from the *.7z file.  The *.tar.lzma file is
+UNIX-style line endings from the *.7z file.  The *.tar.xz file is
 recommended for *NIX users instead.
 
 Version 0.89 was the first official release of libpng.  Don't let the
 fact that it's the first release fool you.  The libpng library has been in
 extensive use and testing since mid-1995.  By late 1997 it had
 finally gotten to the stage where there hadn't been significant
 changes to the API in some time, and people have a bad feeling about
 libraries with versions < 1.0.  Version 1.0.0 was released in
 March 1998.
 
@@ skipping 29 matching lines @@
 
 The additions since 0.89 include the ability to read from a PNG stream
 which has had some (or all) of the signature bytes read by the calling
 application.  This also allows the reading of embedded PNG streams that
 do not have the PNG file signature.  As well, it is now possible to set
 the library action on the detection of chunk CRC errors.  It is possible
 to set different actions based on whether the CRC error occurred in a
 critical or an ancillary chunk.
 
 The changes made to the library, and bugs fixed are based on discussions
-on the png-mng-implement mailing list
-and not on material submitted privately to Guy, Andreas, or Glenn.  They will
-forward any good suggestions to the list.
+on the png-mng-implement mailing list and not on material submitted
+privately to Guy, Andreas, or Glenn.  They will forward any good
+suggestions to the list.
 
 For a detailed description on using libpng, read libpng.txt.  For
 examples of libpng in a program, see example.c and pngtest.c.  For usage
 information and restrictions (what little they are) on libpng, see
 png.h.  For a description on using zlib (the compression library used by
 libpng) and zlib's restrictions, see zlib.h
 
 I have included a general makefile, as well as several machine and
 compiler specific ones, but you may have to modify one for your own needs.
 
@@ skipping 24 matching lines @@
 and any modifications you needed to make to get libpng to compile,
 along with a #define variable to tell what compiler/system you are on.
 If you needed to add transformations to libpng, or wish libpng would
 provide the image in a different way, drop me a note (and code, if
 possible), so I can consider supporting the transformation.
 Finally, if you get any warning messages when compiling libpng
 (note: not zlib), and they are easy to fix, I'd appreciate the
 fix.  Please mention "libpng" somewhere in the subject line.  Thanks.
 
 This release was created and will be supported by myself (of course
-based in a large way on Guy's and Andreas' earlier work), and the PNG group.
+based in a large way on Guy's and Andreas' earlier work), and the PNG
+development group.
 
 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
 
 You can't reach Guy, the original libpng author, at the addresses
-given in previous versions of this document.  He and Andreas will read mail
-addressed to the png-mng-implement list, however.
+given in previous versions of this document.  He and Andreas will
+read mail addressed to the png-mng-implement list, however.
 
 Please do not send general questions about PNG.  Send them to
 the (png-mng-misc at lists.sourceforge.net, subscription required, visit
-https://lists.sourceforge.net/lists/listinfo/png-mng-implement to subscribe)
-On the other hand,
-please do not send libpng questions to that address, send them to me
-or to the png-mng-implement list.  I'll
+https://lists.sourceforge.net/lists/listinfo/png-mng-misc to
+subscribe). On the other hand, please do not send libpng questions to
+that address, send them to me or to the png-mng-implement list.  I'll
 get them in the end anyway.  If you have a question about something
 in the PNG specification that is related to using libpng, send it
 to me.  Send me any questions that start with "I was using libpng,
 and ...".  If in doubt, send questions to me.  I'll bounce them
 to others, if necessary.
 
 Please do not send suggestions on how to change PNG.  We have
 been discussing PNG for twelve years now, and it is official and
 finished.  If you have suggestions for libpng, however, I'll
 gladly listen.  Even if your suggestion is not used immediately,
@@ skipping 33 matching lines @@
       pngtrans.c    =>  Common data transformation functions
       pngwio.c      =>  Lowest-level write I/O functions
       pngwrite.c    =>  High-level write functions
       pngwtran.c    =>  Write data transformations
       pngwutil.c    =>  Write utility functions
       contrib       =>  Contributions
        gregbook         =>  source code for PNG reading and writing, from
                             Greg Roelofs' "PNG: The Definitive Guide",
                             O'Reilly, 1999
        msvctest     =>  Builds and runs pngtest using a MSVC workspace
+       pngminim     =>  Simple pnm2pngm and png2pnmm programs
        pngminus     =>  Simple pnm2png and png2pnm programs
        pngsuite     =>  Test images
        visupng      =>  Contains a MSVC workspace for VisualPng
-      projects      =>  Contains project files and workspaces for building DLL
+      projects      =>  Contains project files and workspaces for
+                        building a DLL
        beos             =>  Contains a Beos workspace for building libpng
-       c5builder        =>  Contains a Borland workspace for building libpng
-                            and zlib
-       visualc6         =>  Contains a Microsoft Visual C++ (MSVC) workspace
-                            for building libpng and zlib
-       netware.txt      =>  Contains instructions for downloading a set of
-                            project files for building libpng and zlib on
-                            Netware.
-       wince.txt        =>  Contains instructions for downloading a Microsoft
-                            Visual C++ (Windows CD Toolkit) workspace for
-                            building libpng and zlib on WindowsCE
+       c5builder        =>  Contains a Borland workspace for building
+                            libpng and zlib
+       netware.txt      =>  Contains instructions for downloading a set
+                            of project files for building libpng and
+                            zlib on Netware.
+       visualc6         =>  Contains a Microsoft Visual C++ (MSVC)
+                            workspace for building libpng and zlib
+       wince.txt        =>  Contains instructions for downloading a
+                            Microsoft Visual C++ (Windows CD Toolkit)
+                            workspace for building libpng and zlib on
+                            WindowsCE
+       xcode            =>  Contains xcode project files
       scripts       =>  Directory containing scripts for building libpng:
        descrip.mms      =>  VMS makefile for MMS or MMK
-       makefile.std     =>  Generic UNIX makefile (cc, creates static libpng.a)
-       makefile.elf     =>  Linux/ELF makefile symbol versioning,
-                            gcc, creates libpng12.so.0.1.2.37)
-       makefile.linux   =>  Linux/ELF makefile
-                            (gcc, creates libpng12.so.0.1.2.37)
-       makefile.gcmmx   =>  Linux/ELF makefile
-                            (gcc, creates libpng12.so.0.1.2.37,
-                            uses assembler code tuned for Intel MMX platform)
-       makefile.gcc     =>  Generic makefile (gcc, creates static libpng.a)
-       makefile.knr     =>  Archaic UNIX Makefile that converts files with
-                            ansi2knr (Requires ansi2knr.c from
+       makefile.std     =>  Generic UNIX makefile (cc, creates static
+                            libpng.a)
+       makefile.elf     =>  Linux/ELF gcc makefile symbol versioning,
+                            creates libpng12.so.0.1.2.43)
+       makefile.linux   =>  Linux/ELF makefile (gcc, creates
+                            libpng12.so.0.1.2.43)
+       makefile.gcmmx   =>  Linux/ELF makefile (gcc, creates
+                            libpng12.so.0.1.2.43, previously
+                            used assembler code tuned for Intel MMX
+                            platform)
+       makefile.gcc     =>  Generic makefile (gcc, creates static
+                            libpng.a)
+       makefile.knr     =>  Archaic UNIX Makefile that converts files
+                            with ansi2knr (Requires ansi2knr.c from
                             ftp://ftp.cs.wisc.edu/ghost)
        makefile.aix     =>  AIX makefile
        makefile.cygwin  =>  Cygwin/gcc makefile
        makefile.darwin  =>  Darwin makefile
        makefile.dec     =>  DEC Alpha UNIX makefile
        makefile.freebsd =>  FreeBSD makefile
        makefile.hpgcc   =>  HPUX makefile using gcc
        makefile.hpux    =>  HPUX (10.20 and 11.00) makefile
        makefile.hp64    =>  HPUX (10.20 and 11.00) makefile, 64 bit
-       makefile.ibmc    =>  IBM C/C++ version 3.x for Win32 and OS/2 (static)
+       makefile.ibmc    =>  IBM C/C++ version 3.x for Win32 and OS/2
+                            (static)
        makefile.intel   =>  Intel C/C++ version 4.0 and later
        libpng.icc       =>  Project file, IBM VisualAge/C++ 4.0 or later
-       makefile.netbsd  =>  NetBSD/cc makefile, PNGGCCRD, makes libpng.so.
-       makefile.ne12bsd  =>  NetBSD/cc makefile, PNGGCCRD, makes libpng12.so
+       makefile.netbsd  =>  NetBSD/cc makefile, makes libpng.so.
+       makefile.ne12bsd  =>  NetBSD/cc makefile, makes libpng12.so
        makefile.openbsd =>  OpenBSD makefile
        makefile.sgi     =>  Silicon Graphics IRIX (cc, creates static lib)
        makefile.sggcc   =>  Silicon Graphics
-                            (gcc, creates libpng12.so.0.1.2.37)
+                            (gcc, creates libpng12.so.0.1.2.43)
        makefile.sunos   =>  Sun makefile
        makefile.solaris =>  Solaris 2.X makefile
-                            (gcc, creates libpng12.so.0.1.2.37)
+                            (gcc, creates libpng12.so.0.1.2.43)
        makefile.so9     =>  Solaris 9 makefile
-                            (gcc, creates libpng12.so.0.1.2.37)
+                            (gcc, creates libpng12.so.0.1.2.43)
        makefile.32sunu  =>  Sun Ultra 32-bit makefile
        makefile.64sunu  =>  Sun Ultra 64-bit makefile
        makefile.sco     =>  For SCO OSr5  ELF and Unixware 7 with Native cc
        makefile.mips    =>  MIPS makefile
        makefile.acorn   =>  Acorn makefile
        makefile.amiga   =>  Amiga makefile
        smakefile.ppc    =>  AMIGA smakefile for SAS C V6.58/7.00 PPC
                             compiler (Requires SCOPTIONS, copied from
                             scripts/SCOPTIONS.ppc)
        makefile.atari   =>  Atari makefile
        makefile.beos    =>  BEOS makefile for X86
        makefile.bor     =>  Borland makefile (uses bcc)
        makefile.bc32    =>  32-bit Borland C++ (all modules compiled in C mode)
        makefile.tc3     =>  Turbo C 3.0 makefile
        makefile.dj2     =>  DJGPP 2 makefile
        makefile.msc     =>  Microsoft C makefile
        makefile.vcawin32=>  makefile for Microsoft Visual C++ 5.0 and
-                            later (uses assembler code tuned for Intel MMX
-                            platform)
+                            later (previously used assembler code tuned
+                            for Intel MMX platform)
        makefile.vcwin32 =>  makefile for Microsoft Visual C++ 4.0 and
                             later (does not use assembler code)
        makefile.os2     =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
        pngos2.def       =>  OS/2 module definition file used by makefile.os2
        makefile.watcom  =>  Watcom 10a+ Makefile, 32-bit flat memory model
        makevms.com      =>  VMS build script
        SCOPTIONS.ppc    =>  Used with smakefile.ppc
 
 Good luck, and happy coding.
 
--Glenn Randers-Pehrson (current maintainer)
+-Glenn Randers-Pehrson (current maintainer, since 1998)
  Internet: glennrp at users.sourceforge.net
 
 -Andreas Eric Dilger (former maintainer, 1996-1997)
  Internet: adilger at enel.ucalgary.ca
  Web: http://members.shaw.ca/adilger/
 
 -Guy Eric Schalnat (original author and former maintainer, 1995-1996)
  (formerly of Group 42, Inc)
  Internet: gschal at infinet.com