libpng/ANNOUNCE

Libpng 1.5.0beta21 - April 25, 2010

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

   1.5.0beta21.tar.xz (LZMA-compressed, recommended)
   1.5.0beta21.tar.gz
   1.5.0beta21.tar.bz2

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

   lp150b21.zip
   lp150b21.7z

Other information:

   1.5.0beta21-README.txt
   1.5.0beta21-LICENSE.txt

Changes since the last public release (1.4.1):

version 1.5.0beta01 [February 7, 2010]
  Moved declaration of png_struct into private pngstruct.h and png_info
    into pnginfo.h

version 1.5.0beta02 [February 7, 2010]
  Reverted to original png_push_save_buffer() code.

version 1.5.0beta03 [February 8, 2010]
  Return allocated "old_buffer" in png_push_save_buffer() before
    calling png_error().
  Updated configure script to use SO number 15.

version 1.5.0beta04 [February 9, 2010]
  Removed malformed "incomplete struct declaration" of png_info from png.h

version 1.5.0beta05 [February 12, 2010]
  Removed PNG_DEPSTRUCT markup in pngstruct.h and pnginfo.h, and undid the
    linewrapping that it entailed.
  Revised comments in pngstruct.h and pnginfo.h and added pointers to
    the libpng license.
  Changed PNG_INTERNAL to PNG_EXPOSE_INTERNAL_STRUCTURES
  Removed the cbuilder5 project, which has not been updated to 1.4.0.

version 1.4.1beta12 and 1.5.0beta06 [February 14, 2010]
  Fixed type declaration of png_get_chunk_malloc_max() in pngget.c (Daisuke
    Nishikawa)

version 1.5.0beta07 [omitted]

version 1.5.0beta08 [February 19, 2010]
  Changed #ifdef PNG_NO_STDIO_SUPPORTED to #ifdef PNG_NO_CONSOLE_IO_SUPPORTED
    wherever png_snprintf() is used to construct error and warning messages.
  Noted in scripts/makefile.mingw that it expects to be run under MSYS.
  Removed obsolete unused MMX-querying support from contrib/gregbook
  Added exported png_longjmp() function.
  Removed the AIX redefinition of jmpbuf in png.h
  Added -D_ALLSOURCE in configure.ac, makefile.aix, and CMakeLists.txt
    when building on AIX.

version 1.5.0beta09 [February 19, 2010]
  Removed -D_ALLSOURCE from configure.ac, makefile.aix, and CMakeLists.txt.
  Changed the name of png_ptr->jmpbuf to png_ptr->png_jmpbuf in pngstruct.h

version 1.5.0beta10 [February 25, 2010]
  Removed unused gzio.c from contrib/pngminim gather and makefile scripts
  Removed replacement error handlers from contrib/gregbook.  Because of
    the new png_longjmp() function they are no longer needed.

version 1.5.0beta11 [March 6, 2010]
  Removed checking for already-included setjmp.h from pngconf.h
  Fixed inconsistent indentations and made numerous cosmetic changes.

version 1.5.0beta12 [March 9, 2010]
  Moved "#include png.h" inside pngpriv.h and removed "#include png.h" from
    the source files, along with "#define PNG_EXPOSE_INTERNAL_STRUCTURES"
    and "#define PNG_NO_PEDANTIC_WARNINGS" (John Bowler).
  Created new pngdebug.h and moved debug definitions there.

version 1.5.0beta13 [March 10, 2010]
  Protect pngstruct.h, pnginfo.h, and pngdebug.h from being included twice.
  Revise the "#ifdef" blocks in png_inflate() so it will compile when neither
    PNG_USER_CHUNK_MALLOC_MAX nor PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
    is defined.
  Removed unused png_measure_compressed_chunk() from pngpriv.h and libpngpf.3
  Moved the 'config.h' support from pngconf.h to pngpriv.h
  Removed PNGAPI from the png_longjmp_ptr typedef.
  Eliminated dependence of pngtest.c on the private pngdebug.h file.
  Make all png_debug macros into *unterminated* statements or
    expressions (i.e. a trailing ';' must always be added) and correct
    the format statements in various png_debug messages.

version 1.5.0beta14 [March 14, 2010]
  Removed direct access to png_ptr->io_ptr from the Windows code in pngtest.c
  Revised Makefile.am to account for recent additions and replacements.
  Corrected CE and OS/2 DEF files (scripts/png*def) for symbols removed and
    added ordinal numbers to the Windows DEF file and corrected the duplicated
    ordinal numbers on CE symbols that are commented out.
  Added back in export symbols that can be present in the Windows build but
    are disabled by default.
  PNG_EXPORT changed to include an 'ordinal' field for DEF file generation.
    PNG_CALLBACK added to make callback definitions uniform.  PNGAPI split
    into PNGCAPI (base C form), PNGAPI (exports) and PNGCBAPI (callbacks),
    and appropriate changes made to all files.  Cygwin builds re-hinged to
    allow procedure call standard changes and to remove the need for the DEF
    file (fixes build on Cygwin).
  Enabled 'attribute' warnings that are relevant to library APIs and callbacks.
  Changed rules for generation of the various symbol files and added a new
    rule for a DEF file (which is also added to the distribution).
  Updated the symbol file generation to stop it adding spurious spaces
    to EOL (coming from preprocessor macro expansion).  Added a facility
    to join tokens in the output and rewrite *.dfn to use this.
  Eliminated scripts/*.def in favor of libpng.def; updated projects/visualc71
    and removed scripts/makefile.cygwin.
  Made PNG_BUILD_DLL safe: it can be set whenever a DLL is being built.
  Removed the include of sys/types.h - apparently unnecessary now on the
    platforms on which it happened (all but Mac OS and RISC OS).
  Moved the Mac OS test into pngpriv.h (the only place it is used.)

version 1.5.0beta15 [March 17, 2010]
  Added symbols.chk target to Makefile.am to validate the symbols in png.h
    against the new DEF file scripts/symbols.def.
  Changed the default DEF file back to pngwin.def.
  Removed makefile.mingw.
  Eliminated PNG_NO_EXTERN and PNG_ALL_EXTERN

version 1.5.0beta16 [April 1, 2010]
  Made png_text_struct independent of PNG_iTXt_SUPPORTED, so that
    fields are initialized in all configurations.  The READ/WRITE
    macros (PNG_(READ|WRITE)_iTXt_SUPPORTED) still function as
    before to disable code to actually read or write iTXt chunks
    and iTXt_SUPPORTED can be used to detect presence of either
    read or write support (but it is probably better to check for
    the one actually required - read or write.)
  Combined multiple png_warning() calls for a single error.
  Restored the macro definition of png_check_sig().

version 1.5.0beta17 [April 17, 2010]
  Documented the fact that png_set_dither() was disabled since libpng-1.4.0.
  Reenabled png_set_dither() but renamed it to png_set_quantize() to reflect
    more accurately what it actually does.  At the same time, renamed
    the PNG_DITHER_[RED,GREEN_BLUE]_BITS macros to
    PNG_QUANTIZE_[RED,GREEN,BLUE]_BITS.
  Added some "(long)" typecasts to printf calls in png_handle_cHRM().
  Freeze build-time only configuration in the build.
    In all prior versions of libpng most configuration options
    controlled by compiler #defines had to be repeated by the
    application code that used libpng.  This patch changes this
    so that compilation options that can only be changed at build
    time are frozen in the build.  Options that are compiler
    dependent (and those that are system dependent) are evaluated
    each time - pngconf.h holds these.  Options that can be changed
    per-file in the application are in png.h.  Frozen options are
    in the new installed header file pnglibconf.h (John Bowler)
  Removed the xcode project because it has not been updated to work
    with libpng-1.5.0.

version 1.5.0beta18 [April 17, 2010]
  Restored the ability to include optional pngusr.h
  Moved replacements for png_error() and png_warning() from the
    contrib/pngminim project to pngerror.c, for use when warnings or
    errors are disabled via PNG_NO_WARN or PNG_NO_ERROR_TEXT, to avoid
    storing unneeded error/warning text.
  Updated contrib/pngminim project to work with the new pnglibconf.h
  Added some PNG_NO_* defines to contrib/pngminim/*/pngusr.h to save space.

version 1.5.0beta19 [April 24, 2010]
  Added PNG_{READ,WRITE}_INT_FUNCTIONS_SUPPORTED.  This allows the functions
    to read and write ints to be disabled independently of PNG_USE_READ_MACROS,
    which allows libpng to be built with the functions even though the default
    is to use the macros - this allows applications to choose at app build
    time whether or not to use macros (previously impossible because the
    functions weren't in the default build.)
  Changed Windows calling convention back to __cdecl for API functions.
    For Windows/x86 platforms only:
      __stdcall is no longer needed for Visual Basic, so libpng-1.5.0 uses
      __cdecl throughout (both API functions and callbacks) on Windows/x86
      platforms.
  Replaced visualc6 and visualc71 projects with new vstudio project 
  Relaxed the overly-restrictive permissions of some files.

version 1.5.0beta20 [April 24, 2010]
  Relaxed more overly-restrictive permissions of some files.

version 1.5.0beta21 [April 25, 2010]
  Trivial editing; changed CRLF to NEWLINE in the new vstudio project files.

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