Imported from libpng-1.0.4.tar

ANNOUNCE

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+
+Libpng 1.0.4 - September 19, 1999
+
+This is a public release of libpng, intended for use in production codes.
+
+Changes since the last public release (1.0.3):
+
+  Added check for PNG_READ_INTERLACE_SUPPORTED in pngread.c; issue a warning
+     if an attempt is made to read an interlaced image when it's not supported.
+  Added check if png_ptr->trans is defined before free'ing it in pngread.c
+  Modified the Y2K statement to include versions back to version 0.71
+  Fixed a bug in the check for valid IHDR bit_depth/color_types in pngrutil.c
+  Modified makefile.wat (added -zp8 flag, ".symbolic", changed some comments)
+  Replaced leading blanks with tab characters in makefile.hux
+  Changed "dworkin.wustl.edu" to "ccrc.wustl.edu" in various documents.
+  Changed (float)red and (float)green to (double)red, (double)green
+     in png_set_rgb_to_gray() to avoid "promotion" problems in AIX.
+  Fixed a bug in pngconf.h that omitted <stdio.h> when PNG_DEBUG==0 (K Bracey).
+  Reformatted libpng.3 and libpngpf.3 with proper fonts (script by J. vanZandt).
+  Updated documentation to refer to the PNG-1.2 specification.
+  Removed ansi2knr.c and left pointers to the latest source for ansi2knr.c
+    in makefile.knr, INSTALL, and README (L. Peter Deutsch)
+  Fixed bugs in calculation of the length of rowbytes when adding alpha
+    channels to 16-bit images, in pngrtran.c (Chris Nokleberg)
+  Added function png_set_user_transform_info() to store user_transform_ptr,
+    user_depth, and user_channels into the png_struct, and a function
+    png_get_user_transform_ptr() to retrieve the pointer (Chris Nokleberg)
+  Added function png_set_empty_plte_permitted() to make libpng useable
+    in MNG applications.
+  Corrected the typedef for png_free_ptr in png.h (Jesse Jones).
+  Correct gamma with srgb is 45455 instead of 45000 in pngrutil.c, to be
+    consistent with PNG-1.2, and allow variance of 500 before complaining.
+  Added assembler code contributed by Intel in file pngvcrd.c and modified
+    makefile.w32 to use it (Nirav Chhatrapati, INTEL Corporation, Gilles Vollant)
+  Define PNG_USE_PNGVCRD in makefile.w32, to get MMX assembler code.
+  Changed "ln -s -f" to "ln -f -s" in the makefiles to make Solaris happy.
+  Added makefile.beo for BEOS on X86, contributed by Sander Stok.
+  Replaced 2147483647L several places with PNG_MAX_UINT macro, defined in png.h
+  Changed leading blanks to tabs in all makefiles.
+  Made alternate versions of  png_set_expand() in pngrtran.c, namely
+    png_set_gray_1_2_4_to_8, png_set_palette_to_rgb, and png_set_tRNS_to_alpha
+    (Greg Roelofs, in "PNG: The Definitive Guide").
+  Relocated start of 'extern "C"' block in png.h so it doesn't include pngconf.h
+  Revised calculation of num_blocks in pngmem.c to avoid a potentially
+    negative shift distance, whose results are undefined in the C language.
+  Added a check in pngset.c to prevent writing multiple tIME chunks.
+  Added a check in pngwrite.c to detect invalid small window_bits sizes.
+  Added a demo read_user_transform_fn that examines the row filters in pngtest.c
+  Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined
+  Made several minor corrections to pngtest.c
+  Changed "hptr += 16L" to "hptr = hptr + 16L" in pngmem.c for Turbo 3.0
+  Renamed the makefiles with longer but more user friendly extensions.
+  Copied the PNG copyright and license to a separate LICENSE file.
+
+Send comments/corrections/commendations to
+png-implement@ccrc.wustl.edu or to randeg@alum.rpi.edu
+
+Glenn R-P

CHANGES

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+CHANGES - changes for libpng
+
+version 0.2
+  added reader into png.h
+  fixed small problems in stub file
+version 0.3
+  added pull reader
+  split up pngwrite.c to several files
+  added pnglib.txt
+  added example.c
+  cleaned up writer, adding a few new tranformations
+  fixed some bugs in writer
+  interfaced with zlib 0.5
+  added K&R support
+  added check for 64 KB blocks for 16 bit machines
+version 0.4
+  cleaned up code and commented code
+  simplified time handling into png_time
+  created png_color_16 and png_color_8 to handle color needs
+  cleaned up color type defines
+  fixed various bugs
+  made various names more consistant
+  interfaced with zlib 0.71
+  cleaned up zTXt reader and writer (using zlib's Reset functions)
+  split transformations into pngrtran.c and pngwtran.c
+version 0.5
+  interfaced with zlib 0.8
+  fixed many reading and writing bugs
+  saved using 3 spaces instead of tabs
+version 0.6
+  added png_large_malloc() and png_large_free()
+  added png_size_t
+  cleaned up some compiler warnings
+  added png_start_read_image()
+version 0.7
+  cleaned up lots of bugs
+  finished dithering and other stuff
+  added test program
+  changed name from pnglib to libpng
+version 0.71 [June, 1995]
+  changed pngtest.png for zlib 0.93
+  fixed error in libpng.txt and example.c
+version 0.8
+  cleaned up some bugs
+  added png_set_filler()
+  split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
+  added #define's to remove unwanted code
+  moved png_info_init() to png.c
+  added old_size into png_realloc()
+  added functions to manually set filtering and compression info
+  changed compression parameters based on image type
+  optimized filter selection code
+  added version info
+  changed external functions passing floats to doubles (k&r problems?)
+  put all the configurable stuff in pngconf.h
+  enabled png_set_shift to work with paletted images on read
+  added png_read_update_info() - updates info structure with
+     transformations
+version 0.81 [August, 1995]
+  incorporated Tim Wegner's medium model code (thanks, Tim)
+version 0.82 [September, 1995]
+  [unspecified changes]
+version 0.85 [December, 1995]
+  added more medium model code (almost everything's a far)
+  added i/o, error, and memory callback functions
+  fixed some bugs (16 bit, 4 bit interlaced, etc.)
+  added first run progressive reader (barely tested)
+version 0.86 [January, 1996]
+  fixed bugs
+  improved documentation
+version 0.87 [January, 1996]
+  fixed medium model bugs
+  fixed other bugs introduced in 0.85 and 0.86
+  added some minor documentation
+version 0.88 [January, 1996]
+  fixed progressive bugs
+  replaced tabs with spaces
+  cleaned up documentation
+  added callbacks for read/write and warning/error functions
+version 0.89 [July, 1996]
+  added new initialization API to make libpng work better with shared libs
+     we now have png_create_read_struct(), png_create_write_struct(),
+     png_create_info_struct(), png_destroy_read_struct(), and
+     png_destroy_write_struct() instead of the separate calls to
+     malloc and png_read_init(), png_info_init(), and png_write_init()
+  changed warning/error callback functions to fix bug - this means you
+     should use the new initialization API if you were using the old
+     png_set_message_fn() calls, and that the old API no longer exists
+     so that people are aware that they need to change their code
+  changed filter selection API to allow selection of multiple filters
+     since it didn't work in previous versions of libpng anyways
+  optimized filter selection code
+  fixed png_set_background() to allow using an arbitrary RGB color for
+     paletted images
+  fixed gamma and background correction for paletted images, so
+     png_correct_palette is not needed unless you are correcting an
+     external palette (you will need to #define PNG_CORRECT_PALETTE_SUPPORTED
+     in pngconf.h) - if nobody uses this, it may disappear in the future.
+  fixed bug with Borland 64K memory allocation (Alexander Lehmann)
+  fixed bug in interlace handling (Smarasderagd, I think)
+  added more error checking for writing and image to reduce invalid files
+  separated read and write functions so that they won't both be linked
+     into a binary when only reading or writing functionality is used
+  new pngtest image also has interlacing and zTXt
+  updated documentation to reflect new API
+version 0.90 [January, 1997]
+  made CRC errors/warnings on critical and ancillary chunks configurable
+  libpng will use the zlib CRC routines by (compile-time) default
+  changed DOS small/medium model memory support - needs zlib 1.04 (Tim Wegner)
+  added external C++ wrapper statements to png.h (Gilles Dauphin)
+  allow PNG file to be read when some or all of file signature has already
+     been read from the beginning of the stream.  ****This affects the size
+     of info_struct and invalidates all programs that use a shared libpng****
+  fixed png_filler() declarations
+  fixed? background color conversions
+  fixed order of error function pointers to match documentation
+  current chunk name is now available in png_struct to reduce the number
+     of nearly identical error messages (will simplify multi-lingual
+     support when available)
+  try to get ready for unknown-chunk callback functions:
+     - previously read critical chunks are flagged, so the chunk handling
+       routines can determine if the chunk is in the right place
+     - all chunk handling routines have the same prototypes, so we will
+       be able to handle all chunks via a callback mechanism
+  try to fix Linux "setjmp" buffer size problems
+version 0.95 [March, 1997]
+  fixed bug in pngwutil.c allocating "up_row" twice and "avg_row" never
+  fixed bug in PNG file signature compares when start != 0
+  changed parameter type of png_set_filler(...filler...) from png_byte
+     to png_uint_32
+  added test for MACOS to ensure that both math.h and fp.h are not #included
+  added macros for libpng to be compiled as a Windows DLL (Andreas Kupries)
+  added "packswap" transformation, which changes the endianness of
+     packed-pixel bytes (Kevin Bracey)
+  added "strip_alpha" transformation, which removes the alpha channel of
+     input images without using it (not neccesarily a good idea)
+  added "swap_alpha" transformation, which puts the alpha channel in front
+     of the color bytes instead of after
+  removed all implicit variable tests which assume NULL == 0 (I think)
+  changed several variables to "png_size_t" to show 16/32-bit limitations
+  added new pCAL chunk read/write support
+  added experimental filter selection weighting (Greg Roelofs)
+  removed old png_set_rgbx() and png_set_xrgb() functions that have been
+     obsolete for about 2 years now (use png_set_filler() instead)
+  added macros to read 16- and 32-bit ints directly from buffer, to be
+     used only on those systems that support it (namely PowerPC and 680x0)
+     With some testing, this may become the default for MACOS/PPC systems.
+  only calculate CRC on data if we are going to use it
+  added macros for zTXt compression type PNG_zTXt_COMPRESSION_???
+  added macros for simple libpng debugging output selectable at compile time
+  removed PNG_READ_END_MODE in progressive reader (Smarasderagd)
+  more description of info_struct in libpng.txt and png.h
+  more instructions in example.c
+  more chunk types tested in pngtest.c
+  renamed pngrcb.c to pngset.c, and all png_read_<chunk> functions to be
+     png_set_<chunk>.  We now have corresponding png_get_<chunk>
+     functions in pngget.c to get infomation in info_ptr.  This isolates
+     the application from the internal organization of png_info_struct
+     (good for shared library implementations).
+version 0.96 [May, 1997]
+  fixed serious bug with < 8bpp images introduced in 0.95
+  fixed 256-color transparency bug (Greg Roelofs)
+  fixed up documentation (Greg Roelofs, Laszlo Nyul)
+  fixed "error" in pngconf.h for Linux setjmp() behaviour
+  fixed DOS medium model support (Tim Wegner)
+  fixed png_check_keyword() for case with error in static string text
+  added read of CRC after IEND chunk for embedded PNGs (Laszlo Nyul)
+  added typecasts to quiet compiler errors
+  added more debugging info
+version 0.97 [January, 1998]
+  removed PNG_USE_OWN_CRC capability
+  relocated png_set_crc_action from pngrutil.c to pngrtran.c
+  fixed typecasts of "new_key", etc. (Andreas Dilger)
+  added RFC 1152 [sic] date support
+  fixed bug in gamma handling of 4-bit grayscale
+  added 2-bit grayscale gamma handling (Glenn R-P)
+  added more typecasts. 65536L becomes (png_uint_32)65536L, etc. (Glenn R-P)
+  minor corrections in libpng.txt
+  added simple sRGB support (Glenn R-P)
+  easier conditional compiling, e.g. define PNG_READ/WRITE_NOT_FULLY_SUPPORTED;
+     all configurable options can be selected from command-line instead
+     of having to edit pngconf.h (Glenn R-P)
+  fixed memory leak in pngwrite.c (free info_ptr->text) (Glenn R-P)
+  added more conditions for png_do_background, to avoid changing
+     black pixels to background when a background is supplied and
+     no pixels are transparent
+  repaired PNG_NO_STDIO behaviour
+  tested NODIV support and made it default behaviour (Greg Roelofs)
+  added "-m" option and PNGTEST_DEBUG_MEMORY to pngtest (John Bowler)
+  regularized version numbering scheme and bumped shared-library major
+     version number to 2 to avoid problems with libpng 0.89 apps (Greg Roelofs)
+version 0.98 [January, 1998]
+  cleaned up some typos in libpng.txt and in code documentation
+  fixed memory leaks in pCAL chunk processing (Glenn R-P and John Bowler)
+  cosmetic change "display_gamma" to "screen_gamma" in pngrtran.c
+  changed recommendation about file_gamma for PC images to .51 from .45,
+     in example.c and libpng.txt, added comments to distinguish between
+     screen_gamma, viewing_gamma, and display_gamma.
+  changed all references to RFC1152 to read RFC1123 and changed the
+     PNG_TIME_RFC1152_SUPPORTED macro to PNG_TIME_RFC1123_SUPPORTED
+  added png_invert_alpha capability (Glenn R-P -- suggestion by Jon Vincent)
+  changed srgb_intent from png_byte to int to avoid compiler bugs
+version 0.99 [January 30, 1998]
+  free info_ptr->text instead of end_info_ptr->text in pngread.c (John Bowler)
+  fixed a longstanding "packswap" bug in pngtrans.c
+  fixed some inconsistencies in pngconf.h that prevented compiling with
+     PNG_READ_GAMMA_SUPPORTED and PNG_READ_hIST_SUPPORTED undefined
+  fixed some typos and made other minor rearrangement of libpng.txt (Andreas)
+  changed recommendation about file_gamma for PC images to .50 from .51 in
+     example.c and libpng.txt, and changed file_gamma for sRGB images to .45
+  added a number of functions to access information from the png structure
+     png_get_image_height(), etc. (Glenn R-P, suggestion by Brad Pettit)
+  added TARGET_MACOS similar to zlib-1.0.8
+  define PNG_ALWAYS_EXTERN when __MWERKS__ && WIN32 are defined
+  added type casting to all png_malloc() function calls
+version 0.99a [January 31, 1998]
+  Added type casts and parentheses to all returns that return a value.(Tim W.)
+version 0.99b [February 4, 1998]
+  Added type cast png_uint_32 on malloc function calls where needed.
+  Changed type of num_hist from png_uint_32 to int (same as num_palette).
+  Added checks for rowbytes overflow, in case png_size_t is less than 32 bits.
+  Renamed makefile.elf to makefile.lnx.
+version 0.99c [February 7, 1998]
+  More type casting.  Removed erroneous overflow test in pngmem.c.
+  Added png_buffered_memcpy() and png_buffered_memset(), apply them to rowbytes.
+  Added UNIX manual pages libpng.3 (incorporating libpng.txt) and  png.5.
+version 0.99d [February 11, 1998]
+  Renamed "far_to_near()" "png_far_to_near()"
+  Revised libpng.3
+  Version 99c "buffered" operations didn't work as intended.  Replaced them
+    with png_memcpy_check() and png_memset_check().
+  Added many "if (png_ptr == NULL) return" to quell compiler warnings about
+    unused png_ptr, mostly in pngget.c and pngset.c.
+  Check for overlength tRNS chunk present when indexed-color PLTE is read.
+  Cleaned up spelling errors in libpng.3/libpng.txt
+  Corrected a problem with png_get_tRNS() which returned undefined trans array
+version 0.99e [February 28, 1998]
+  Corrected png_get_tRNS() again.
+  Add parentheses for easier reading of pngget.c, fixed "||" should be "&&".
+  Touched up example.c to make more of it compileable, although the entire
+    file still can't be compiled (Willem van Schaik)
+  Fixed a bug in png_do_shift() (Bryan Tsai)
+  Added a space in png.h prototype for png_write_chunk_start()
+  Replaced pngtest.png with one created with zlib 1.1.1
+  Changed pngtest to report PASS even when file size is different (Jean-loup G.)
+  Corrected some logic errors in png_do_invert_alpha() (Chris Patterson)
+version 0.99f [March 5, 1998]
+  Corrected a bug in pngpread() introduced in version 99c (Kevin Bracey)
+  Moved makefiles into a "scripts" directory, and added INSTALL instruction file
+  Added makefile.os2 and pngos2.def (A. Zabolotny) and makefile.s2x (W. Sebok)
+  Added pointers to "note on libpng versions" in makefile.lnx and README
+  Added row callback feature when reading and writing nonprogressive rows
+     and added a test of this feature in pngtest.c
+  Added user transform callbacks, with test of the feature in pngtest.c
+version 0.99g [March 6, 1998, morning]
+  Minor changes to pngtest.c to suppress compiler warnings.
+  Removed "beta" language from documentation.
+version 0.99h [March 6, 1998, evening]
+  Minor changes to previous minor changes to pngtest.c
+  Changed PNG_READ_NOT_FULLY_SUPPORTED to PNG_READ_TRANSFORMS_NOT_SUPPORTED
+  and added PNG_PROGRESSIVE_READ_NOT_SUPPORTED macro
+version 1.00 [March 7, 1998]
+  Changed several typedefs in pngrutil.c
+  Added makefile.wat (Pawel Mrochen), updated makefile.tc3 (Willem van Schaik)
+  replaced "while(1)" with "for(;;)"
+  added PNGARG() to prototypes in pngtest.c and removed some prototypes
+  updated some of the makefiles (Tom Lane)
+  changed some typedefs (s_start, etc.) in pngrutil.c
+  fixed dimensions of "short_months" array in pngwrite.c
+  Replaced ansi2knr.c with the one from jpeg-v6
+version 1.0.0 [March 8, 1998]
+  Changed name from 1.00 to 1.0.0 (Adam Costello)
+  Added smakefile.ppc (with SCOPTIONS.ppc) for Amiga PPC (Andreas Kleinert)
+version 1.0.0a [March 9, 1998]
+  Fixed three bugs in pngrtran.c to make gamma+background handling consistent
+  (Greg Roelofs)
+  Changed format of the PNG_LIBPNG_VER integer to xyyzz instead of xyz
+  for major, minor, and bugfix releases.  This is 10001. (Adam Costello,
+  Tom Lane)
+  Make months range from 1-12 in png_convert_to_rfc1123
+version 1.0.0b [March 13, 1998]
+  Quieted compiler complaints about two empty "for" loops in pngrutil.c
+  Minor changes to makefile.s2x
+  Removed #ifdef/#endif around a png_free() in pngread.c
+version 1.0.1 [March 14, 1998]
+  Changed makefile.s2x to reduce security risk of using a relative pathname
+  Fixed some typos in the documentation (Greg).
+  Fixed a problem with value of "channels" returned by png_read_update_info()
+version 1.0.1a [April 21, 1998]
+  Optimized Paeth calculations by replacing abs() function calls with intrinsics
+  plus other loop optimizations. Improves avg decoding speed by about 20%.
+  Commented out i386istic "align" compiler flags in makefile.lnx.
+  Reduced the default warning level in some makefiles, to make them consistent.
+  Removed references to IJG and JPEG in the ansi2knr.c copyright statement.
+  Fixed a bug in png_do_strip_filler with XXRRGGBB => RRGGBB transformation.
+  Added grayscale and 16-bit capability to png_do_read_filler().
+  Fixed a bug in pngset.c, introduced in version 0.99c, that sets rowbytes
+    too large when writing an image with bit_depth < 8 (Bob Dellaca).
+  Corrected some bugs in the experimental weighted filtering heuristics.
+  Moved a misplaced pngrutil code block that truncates tRNS if it has more
+    than num_palette entries -- test was done before num_palette was defined.
+  Fixed a png_convert_to_rfc1123() bug that converts day 31 to 0 (Steve Eddins).
+  Changed compiler flags in makefile.wat for better optimization (Pawel Mrochen).
+version 1.0.1b [May 2, 1998]
+  Relocated png_do_gray_to_rgb() within png_do_read_transformations() (Greg).
+  Relocated the png_composite macros from pngrtran.c to png.h (Greg).
+  Added makefile.sco (contributed by Mike Hopkirk).
+  Fixed two bugs (missing definitions of "istop") introduced in libpng-1.0.1a.
+  Fixed a bug in pngrtran.c that would set channels=5 under some circumstances.
+  More work on the Paeth-filtering, achieving imperceptible speedup (A Kleinert).
+  More work on loop optimization which may help when compiled with C++ compilers.
+  Added warnings when people try to use transforms they've defined out.
+  Collapsed 4 "i" and "c" loops into single "i" loops in pngrtran and pngwtran.
+  Revised paragraph about png_set_expand() in libpng.txt and libpng.3 (Greg)
+version 1.0.1c [May 11, 1998]
+  Fixed a bug in pngrtran.c (introduced in libpng-1.0.1a) where the masks for
+    filler bytes should have been 0xff instead of 0xf.
+  Added max_pixel_depth=32 in pngrutil.c when using FILLER with palette images.
+  Moved PNG_WRITE_WEIGHTED_FILTER_SUPPORTED and PNG_WRITE_FLUSH_SUPPORTED
+    out of the PNG_WRITE_TRANSFORMS_NOT_SUPPORTED block of pngconf.h
+  Added "PNG_NO_WRITE_TRANSFORMS" etc., as alternatives for *_NOT_SUPPORTED,
+    for consistency, in pngconf.h
+  Added individual "ifndef PNG_NO_[CAPABILITY]" in pngconf.h to make it easier
+    to remove unwanted capabilities via the compile line
+  Made some corrections to grammar (which, it's) in documentation (Greg).
+  Corrected example.c, use of row_pointers in png_write_image().
+version 1.0.1d [May 24, 1998]
+  Corrected several statements that used side effects illegally in pngrutil.c
+    and pngtrans.c, that were introduced in version 1.0.1b
+  Revised png_read_rows() to avoid repeated if-testing for NULL (A Kleinert)
+  More corrections to example.c, use of row_pointers in png_write_image()
+    and png_read_rows().
+  Added pngdll.mak and pngdef.pas to scripts directory, contributed by
+    Bob Dellaca, to make a png32bd.dll with Borland C++ 4.5
+  Fixed error in example.c with png_set_text: num_text is 3, not 2 (Guido V.)
+  Changed several loops from count-down to count-up, for consistency.
+version 1.0.1e [June 6, 1998]
+  Revised libpng.txt and libpng.3 description of png_set_read|write_fn(), and
+    added warnings when people try to set png_read_fn and png_write_fn in
+    the same structure.
+  Added a test such that png_do_gamma will be done when num_trans==0
+    for truecolor images that have defined a background.  This corrects an
+    error that was introduced in libpng-0.90 that can cause gamma processing
+    to be skipped.
+  Added tests in png.h to include "trans" and "trans_values" in structures
+    when PNG_READ_BACKGROUND_SUPPORTED or PNG_READ_EXPAND_SUPPORTED is defined.
+  Add png_free(png_ptr->time_buffer) in png_destroy_read_struct()
+  Moved png_convert_to_rfc_1123() from pngwrite.c to png.c
+  Added capability for user-provided malloc_fn() and free_fn() functions,
+    and revised pngtest.c to demonstrate their use, replacing the
+    PNGTEST_DEBUG_MEM feature.
+  Added makefile.w32, for Microsoft C++ 4.0 and later (Tim Wegner).
+version 1.0.2 [June 14, 1998]
+  Fixed two bugs in makefile.bor .
+version 1.0.2a [December 30, 1998]
+  Replaced and extended code that was removed from png_set_filler() in 1.0.1a.
+  Fixed a bug in png_do_filler() that made it fail to write filler bytes in
+    the left-most pixel of each row (Kevin Bracey).
+  Changed "static pngcharp tIME_string" to "static char tIME_string[30]"
+    in pngtest.c (Duncan Simpson).
+  Fixed a bug in pngtest.c that caused pngtest to try to write a tIME chunk
+    even when no tIME chunk was present in the source file.
+  Fixed a problem in pngrutil.c: gray_to_rgb didn't always work with 16-bit.
+  Fixed a problem in png_read_push_finish_row(), which would not skip some
+    passes that it should skip, for images that are less than 3 pixels high.
+  Interchanged the order of calls to png_do_swap() and png_do_shift()
+    in pngwtran.c (John Cromer).
+  Added #ifdef PNG_DEBUG/#endif surrounding use of PNG_DEBUG in png.h .
+  Changed "bad adaptive filter type" from error to warning in pngrutil.c .
+  Fixed a documentation error about default filtering with 8-bit indexed-color.
+  Separated the PNG_NO_STDIO macro into PNG_NO_STDIO and PNG_NO_CONSOLE_IO
+    (L. Peter Deutsch).
+  Added png_set_rgb_to_gray() and png_get_rgb_to_gray_status() functions.
+  Added png_get_copyright() and png_get_header_version() functions.
+  Revised comments on png_set_progressive_read_fn() in libpng.txt and example.c
+  Added information about debugging in libpng.txt and libpng.3 .
+  Changed "ln -sf" to "ln -s -f" in makefile.s2x, makefile.lnx, and makefile.sco.
+  Removed lines after Dynamic Dependencies" in makefile.aco .
+  Revised makefile.dec to make a shared library (Jeremie Petit).
+  Removed trailing blanks from all files. 
+version 1.0.2a [January 6, 1999]
+  Removed misplaced #endif and #ifdef PNG_NO_EXTERN near the end of png.h
+  Added "if" tests to silence complaints about unused png_ptr in png.h and png.c
+  Changed "check_if_png" function in example.c to return true (nonzero) if PNG.
+  Changed libpng.txt to demonstrate png_sig_cmp() instead of png_check_sig()
+    which is obsolete.
+version 1.0.3 [January 14, 1999]
+  Added makefile.hux, for Hewlett Packard HPUX 10.20 and 11.00 (Jim Rice)
+  Added a statement of Y2K compliance in png.h, libpng.3, and Y2KINFO.
+version 1.0.3a [August 12, 1999]
+  Added check for PNG_READ_INTERLACE_SUPPORTED in pngread.c; issue a warning
+     if an attempt is made to read an interlaced image when it's not supported.
+  Added check if png_ptr->trans is defined before free'ing it in pngread.c
+  Modified the Y2K statement to include versions back to version 0.71
+  Fixed a bug in the check for valid IHDR bit_depth/color_types in pngrutil.c
+  Modified makefile.wat (added -zp8 flag, ".symbolic", changed some comments)
+  Replaced leading blanks with tab characters in makefile.hux
+  Changed "dworkin.wustl.edu" to "ccrc.wustl.edu" in various documents.
+  Changed (float)red and (float)green to (double)red, (double)green
+     in png_set_rgb_to_gray() to avoid "promotion" problems in AIX.
+  Fixed a bug in pngconf.h that omitted <stdio.h> when PNG_DEBUG==0 (K Bracey).
+  Reformatted libpng.3 and libpngpf.3 with proper fonts (script by J. vanZandt).
+  Updated documentation to refer to the PNG-1.2 specification.
+  Removed ansi2knr.c and left pointers to the latest source for ansi2knr.c
+    in makefile.knr, INSTALL, and README (L. Peter Deutsch)
+  Fixed bugs in calculation of the length of rowbytes when adding alpha
+    channels to 16-bit images, in pngrtran.c (Chris Nokleberg)
+  Added function png_set_user_transform_info() to store user_transform_ptr,
+    user_depth, and user_channels into the png_struct, and a function
+    png_get_user_transform_ptr() to retrieve the pointer (Chris Nokleberg)
+  Added function png_set_empty_plte_permitted() to make libpng useable
+    in MNG applications.
+  Corrected the typedef for png_free_ptr in png.h (Jesse Jones).
+  Correct gamma with srgb is 45455 instead of 45000 in pngrutil.c, to be
+    consistent with PNG-1.2, and allow variance of 500 before complaining.
+  Added assembler code contributed by Intel in file pngvcrd.c and modified
+    makefile.w32 to use it (Nirav Chhatrapati, INTEL Corporation, Gilles Vollant)
+  Changed "ln -s -f" to "ln -f -s" in the makefiles to make Solaris happy.
+  Added some aliases for png_set_expand() in pngrtran.c, namely
+    png_set_expand_PLTE(), png_set_expand_depth(), and png_set_expand_tRNS()
+    (Greg Roelofs, in "PNG: The Definitive Guide").
+  Added makefile.beo for BEOS on X86, contributed by Sander Stok.
+version 1.0.3b [August 26, 1999]
+  Replaced 2147483647L several places with PNG_MAX_UINT macro, defined in png.h
+  Changed leading blanks to tabs in all makefiles.
+  Define PNG_USE_PNGVCRD in makefile.w32, to get MMX assembler code.
+  Made alternate versions of  png_set_expand() in pngrtran.c, namely
+    png_set_gray_1_2_4_to_8, png_set_palette_to_rgb, and png_set_tRNS_to_alpha
+    (Greg Roelofs, in "PNG: The Definitive Guide").  Deleted the 1.0.3a aliases.
+  Relocated start of 'extern "C"' block in png.h so it doesn't include pngconf.h
+  Revised calculation of num_blocks in pngmem.c to avoid a potentially
+    negative shift distance, whose results are undefined in the C language.
+  Added a check in pngset.c to prevent writing multiple tIME chunks.
+  Added a check in pngwrite.c to detect invalid small window_bits sizes.
+version 1.0.3d [September 4, 1999]
+  Fixed type casting of igamma in pngrutil.c
+  Added new png_expand functions to scripts/pngdef.pas and pngos2.def
+  Added a demo read_user_transform_fn that examines the row filters in pngtest.c
+version 1.0.4 [September 19, 1999]
+  Define PNG_ALWAYS_EXTERN in pngconf.h if __STDC__ is defined
+  Delete #define PNG_INTERNAL and include "png.h" from pngasmrd.h
+  Made several minor corrections to pngtest.c
+  Renamed the makefiles with longer but more user friendly extensions.
+  Copied the PNG copyright and license to a separate LICENSE file.

INSTALL

@@ -0,0 +1,96 @@
+
+Installing libpng version 1.0.4 - September 19, 1999
+
+Before installing libpng, you must first install zlib.  zlib
+can usually be found wherever you got libpng.  zlib can be
+placed in another directory, at the same level as libpng.
+Note that your system might already have a preinstalled
+zlib, but you will still need to have access to the
+zlib.h and zconf.h include files that correspond to the
+version of zlib that's installed.
+
+You can rename the directories that you downloaded (they
+might be called "libpng-1.0.4" or "lpng103" and "zlib-1.1.3"
+or "zlib113") so that you have directories called "zlib" and "libpng".
+
+Your directory structure should look like this:
+
+   ..       (the parent directory)
+      libpng  (this directory)
+          INSTALL (this file)
+          README
+          *.h
+          *.c
+          scripts
+             makefile.*
+          pngtest.png
+          etc.
+      zlib
+          README
+          *.h
+          *.c
+          contrib
+          etc.
+
+First enter the zlib directory and follow the instructions
+in zlib/README.  Then come back here and choose the
+appropriate makefile.sys in the scripts directory.
+The files that are presently available in the scripts directory
+include
+
+ descrip.mms      =>  VMS makefile for MMS or MMK
+ makefile.std     =>  Generic UNIX makefile
+ makefile.knr     =>  Archaic UNIX Makefile that converts files with
+                      ansi2knr (Requires ansi2knr.c from
+                      ftp://ftp.cs.wisc.edu/ghost)
+ makefile.dec     =>  DEC Alpha UNIX makefile
+ makefile.hpux    =>  HPUX (10.20 and 11.00) makefile
+ makefile.sgi     =>  Silicon Graphics IRIX makefile
+ makefile.sunos   =>  Sun makefile
+ makefile.solaris =>  Solaris 2.X makefile (gcc, creates libpng.so.2.1.0.4)
+ makefile.linux   =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.0.4)
+ 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.borland =>  Borland makefile
+ build.bat        =>  MS-DOS batch file for Borland compiler
+ makefile.dj2     =>  DJGPP 2 makefile
+ makefile.msc     =>  Microsoft C makefile
+ makefile.win32vc =>  makefile for Microsoft Visual C++ 4.0 and later
+ makefile.turboc3 =>  Turbo C 3.0 makefile
+ 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
+ pngdll.mak       =>  To make a png32bd.dll with Borland C++ 4.5
+ pngdef.pas       =>  Defines for a png32bd.dll with Borland C++ 4.5
+ SCOPTIONS.ppc    =>  Used with smakefile.ppc
+
+Copy the file (or files) that you need from the
+scripts directory into this directory, for example
+
+   MSDOS example: copy scripts\makefile.msd makefile
+   UNIX example:    cp scripts/makefile.std makefile
+
+Read the makefile to see if you need to change any source or
+target directories to match your preferences.
+
+Then read pngconf.h to see if you want to make any configuration
+changes.
+
+Then just run "make test" which will create the libpng library in
+this directory and run a quick test that reads the "pngtest.png"
+file and writes a "pngout.png" file that should be identical to it.
+
+Most of the makefiles will allow you to run "make install" to
+put the library in its final resting place (if you want to
+do that, run "make install" in the zlib directory first if necessary).
+
+Further information can be found in the README and libpng.txt
+files, in the individual makefiles, and in png.h, and the manual
+pages libpng.3 and png.5.

KNOWNBUG

@@ -0,0 +1,40 @@
+
+Known bugs and suggested enhancements in libpng-1.0.4
+
+
+1. March 15, 1998 -- OPTIMIZATION -- Kevin Bracey
+
+   Loops need to be optimized everywhere
+
+   Make them count down instead of up -- Kevin Bracey
+
+   Optimizing compilers don't need this, and making
+   the change would be error prone -- Tom Lane, Glenn R-P
+
+   Question whether i-- or --i is better.
+
+   STATUS: Under investigation, postponed until after
+   libpng-1.0.4.  About 160 loops will be turned around
+   in libpng-1.0.Nn, for testing.
+
+2. July 4, 1998 -- ENHANCEMENT -- Glenn R-P
+
+   libpng-1.0.4 and earlier transform colors to gamma=1.0 space for
+   merging with background, and then back to the image's gamma.  The
+   bit_depth of the intermediate (gamma=1.0) representation is probably
+   not sufficient.  In the typical gamma=1/2.2 situation, the linear
+   pixels need about 4 more bits than the gamma-encoded ones, to avoid
+   loss of precision.  A similar situation exists with the rgb_to_gray
+   operation.
+
+   STATUS: under development.
+
+3. September 1999 -- ENHANCEMENT --
+
+   It should be possible to use libpng without floating-point aritmetic.
+
+   STATUS: Under investigation, implementation postponed until after
+   libpng-1.0.4.  The application interface will change because replacements
+   for the png_set_gAMA(), png_set_cHRM(), and corresponding png_get_()
+   functions will be needed.
+

LICENSE

@@ -0,0 +1,41 @@
+COPYRIGHT NOTICE:
+
+Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+(libpng versions 0.5, May 1995, through 0.89c, May 1996)
+Copyright (c) 1996, 1997 Andreas Dilger
+(libpng versions 0.90, December 1996, through 0.96, May 1997)
+Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+(libpng versions 0.97, January 1998, through 1.0.4, September 19, 1999)
+
+The PNG Reference Library is supplied "AS IS".  The Contributing Authors
+and Group 42, Inc. disclaim all warranties, expressed or implied,
+including, without limitation, the warranties of merchantability and of
+fitness for any purpose.  The Contributing Authors and Group 42, Inc.
+assume no liability for direct, indirect, incidental, special, exemplary,
+or consequential damages, which may result from the use of the PNG
+Reference Library, even if advised of the possibility of such damage.
+
+Permission is hereby granted to use, copy, modify, and distribute this
+source code, or portions hereof, for any purpose, without fee, subject
+to the following restrictions:
+
+ 1. The origin of this source code must not be
+    misrepresented.
+
+ 2. Altered versions must be plainly marked as such
+    and must not be misrepresented as being the
+    original source.
+
+ 3. This Copyright notice may not be removed or
+    altered from any source or altered source
+    distribution.
+
+The Contributing Authors and Group 42, Inc. specifically permit, without
+fee, and encourage the use of this source code as a component to
+supporting the PNG file format in commercial products.  If you use this
+source code in a product, acknowledgment is not required but would be
+appreciated.
+
+Glenn Randers-Pehrson
+randeg at alum.rpi.edu
+September 19, 1999

README

@@ -0,0 +1,204 @@
+README for libpng 1.0.4 - September 19, 1999 (shared library 2.1)
+See the note about version numbers near the top of png.h
+
+See INSTALL for instructions on how to install libpng.
+
+This is 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 for about two and a half years.  However, it's
+finally gotten to the stage where there haven't been significant
+changes to the API in some time, and people have a bad feeling about
+libraries with versions < 1.0.
+
+****
+Note that some of the changes to the png_info structure render this
+version of the library binary incompatible with libpng-0.89 or
+earlier versions if you are using a shared library.  The type of the
+"filler" parameter for png_set_filler() has changed from png_byte to
+png_uint_32, which will affect shared-library applications that use
+this function.
+
+To avoid problems with changes to the internals of png_info_struct,
+new APIs have been made available in 0.95 to avoid direct application
+access to info_ptr.  These functions are the png_set_<chunk> and
+png_get_<chunk> functions.  These functions should be used when
+accessing/storing the info_struct data, rather than manipulating it
+directly, to avoid such problems in the future.
+
+It is important to note that the APIs do not make current programs
+that access the info struct directly incompatible with the new
+library.  However, it is strongly suggested that new programs use
+the new APIs (as shown in example.c), and older programs be converted
+to the new format, to facilitate upgrades in the future.
+****
+
+Additions since 0.90 include the ability to compile libpng as a
+Windows DLL, and new APIs for accessing data in the info struct.
+Experimental functions include the ability to set weighting and cost
+factors for row filter selection, direct reads of integers from buffers
+on big-endian processors that support misaligned data access, faster
+methods of doing alpha composition, and more accurate 16->8 bit color
+conversion.
+
+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 implementation mailing list <png-implement@ccrc.wustl.edu>
+and not on material submitted to Guy.
+
+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.
+
+You should use zlib 1.0.4 or later to run this, but it MAY work with
+versions as old as zlib 0.95.  Even so, there are bugs in older zlib
+versions which can cause the output of invalid compression streams for
+some images.  You will definitely need zlib 1.0.4 or later if you are
+taking advantage of the MS-DOS "far" structure allocation for the small
+and medium memory models.  You should also note that zlib is a
+compression library that is useful for more things than just PNG files.
+You can use zlib as a drop-in replacement for fread() and fwrite() if
+you are so inclined.
+
+zlib should be available at the same place that libpng is.
+If not, it should be at ftp.uu.net in /graphics/png
+Eventually, it will be at ftp.uu.net in /pub/archiving/zip/zlib
+
+You may also want a copy of the PNG specification.  It is available
+as an RFC and a W3C Recommendation.  Failing
+these resources you can try ftp.uu.net in the /graphics/png directory.
+
+This code is currently being archived at ftp.uu.net in the
+/graphics/png directory, and on CompuServe, Lib 20 (PNG SUPPORT)
+at GO GRAPHSUP.  If you can't find it in any of those places,
+e-mail me, and I'll help you find it.
+
+If you have any code changes, requests, problems, etc., please e-mail
+them to me.  Also, I'd appreciate any make files or project files,
+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.
+
+randeg@alum.rpi.edu
+png-implement@ccrc.wustl.edu
+
+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-implement list, however.
+
+Please do not send general questions about PNG.  Send them to
+the address in the specification (png-group@w3.org).  At the same
+time, please do not send libpng questions to that address, send them to me
+or to png-implement@ccrc.wustl.edu.  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 three 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 for version
+1.0, it may be used later.
+
+Files in this distribution:
+
+      CHANGES       =>  Description of changes between libpng versions
+      README        =>  This file
+      TODO          =>  Things not implemented in the current library
+      build.bat     =>  MS-DOS batch file for Borland compiler
+      descrip.mms   =>  VMS project file
+      example.c     =>  Example code for using libpng functions
+      libpng.3      =>  manual page for libpng
+      libpng.txt    =>  Description of libpng and its functions
+      libpngpf.3    =>  manual page for libpng's private functions
+      png.5         =>  manual page for the PNG format
+      png.c         =>  Basic interface functions common to library
+      png.h         =>  Library function and interface declarations
+      pngconf.h     =>  System specific library configuration
+      pngerror.c    =>  Error/warning message I/O functions
+      pngget.c      =>  Functions for retrieving info from struct
+      pngmem.c      =>  Memory handling functions
+      pngpread.c    =>  Progressive reading functions
+      pngread.c     =>  Read data/helper high-level functions
+      pngrio.c      =>  Lowest-level data read I/O functions
+      pngrtran.c    =>  Read data transformation functions
+      pngrutil.c    =>  Read data utility functions
+      pngset.c      =>  Functions for storing data into the info_struct
+      pngtest.c     =>  Library test program
+      pngtest.png   =>  Library test sample image
+      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
+      scripts       =>  Directory containing scripts for building libpng:
+       descrip.mms      =>  VMS makefile for MMS or MMK
+       makefile.std     =>  Generic UNIX makefile
+       makefile.knr     =>  Archaic UNIX Makefile that converts files with
+                            ansi2knr (Requires ansi2knr.c from
+                            ftp://ftp.cs.wisc.edu/ghost)
+       makefile.dec     =>  DEC Alpha UNIX makefile
+       makefile.hpux    =>  HPUX (10.20 and 11.00) makefile
+       makefile.sgi     =>  Silicon Graphics IRIX makefile
+       makefile.sunos   =>  Sun makefile
+       makefile.solaris =>  Solaris 2.X makefile
+                            (gcc, creates libpng.so.2.1.0.4)
+       makefile.linux   =>  Linux/ELF makefile
+                            (gcc, creates libpng.so.2.1.0.4)
+       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.borland =>  Borland makefile
+       build.bat        =>  MS-DOS batch file for Borland compiler
+       makefile.dj2     =>  DJGPP 2 makefile
+       makefile.msc     =>  Microsoft C makefile
+       makefile.win32vc =>  makefile for Microsoft Visual C++ 4.0 and later
+       makefile.turboc3 =>  Turbo C 3.0 makefile
+       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
+       pngdll.mak       =>  To make a png32bd.dll with Borland C++ 4.5
+       pngdef.pas       =>  Defines for a png32bd.dll with Borland C++ 4.5
+       SCOPTIONS.ppc    =>  Used with smakefile.ppc
+
+Good luck, and happy coding.
+
+-Glenn Randers-Pehrson
+ Internet: randeg@alum.rpi.edu
+ Web: http://www.rpi.edu/~randeg/index.html
+
+-Andreas Eric Dilger
+ Internet: adilger@enel.ucalgary.ca
+ Web: http://www-mddsp.enel.ucalgary.ca/People/adilger/
+
+-Guy Eric Schalnat
+ (formerly of Group 42, Inc)
+ Internet: gschal@infinet.com

TODO

@@ -0,0 +1,24 @@
+TODO - list of things to do for libpng:
+
+Final bug fixes.
+Fix problem with C++ and EXTERN "C".
+Better C++ wrapper/full C++ implementation?
+Keep up with public chunks.
+sPLT chunk handling.
+cHRM transformation.
+Support for application-defined chunk handlers.
+Improve setjmp/longjmp usage or remove it in favor of returning error codes.
+High-level API for reading images.
+Add "grayscale->palette" transformation and "palette->grayscale" detection.
+Improved dithering.
+Multi-lingual error and warning message support.
+Complete sRGB transformation (presently it simply uses gamma=0.45455).
+Man pages for function calls.
+Better documentation.
+Better filter selection
+   (counting huffman bits/precompression?  filter inertia?  filter costs?).
+Optional palette (sPLT) creation.
+Histogram creation.
+Text conversion between different code pages (Latin-1 -> Mac and DOS).
+Improve API by hiding the info_ptr.
+Make a no-floating-point version.

Y2KINFO

@@ -0,0 +1,55 @@
+   Y2K compliance in libpng:
+   =========================
+      
+      September 19, 1999
+      
+      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 1.0.4 are Y2K compliant.  It is my belief that earlier
+      versions were also Y2K compliant.
+      
+      Libpng only has three year fields.  One is a 2-byte unsigned integer
+      that will hold years up to 65535.  The other two hold the date in text
+      format, and will hold years up to 9999.
+      
+      The integer is
+          "png_uint_16 year" in png_time_struct.
+      
+      The strings are
+          "png_charp time_buffer" in png_struct and
+          "near_time_buffer", which is a local character string in png.c.
+      
+      There are seven time-related functions:
+
+          png_convert_to_rfc_1123() in png.c 
+            (formerly png_convert_to_rfc_1152() in error)
+          png_convert_from_struct_tm() in pngwrite.c, called in pngwrite.c
+          png_convert_from_time_t() in pngwrite.c
+          png_get_tIME() in pngget.c
+          png_handle_tIME() in pngrutil.c, called in pngread.c
+          png_set_tIME() in pngset.c
+          png_write_tIME() in pngwutil.c, called in pngwrite.c
+      
+      All appear to handle dates properly in a Y2K environment.  The 
+      png_convert_from_time_t() function calls gmtime() to convert from system
+      clock time, which returns (year - 1900), which we properly convert to
+      the full 4-digit year.  There is a possibility that applications using
+      libpng are not passing 4-digit years into the png_convert_to_rfc_1123()
+      function, or that they are incorrectly passing only a 2-digit year
+      instead of "year - 1900" into the png_convert_from_struct_tm() function,
+      but this is not under our control.  The libpng documentation has always
+      stated that it works with 4-digit years, and the APIs have been
+      documented as such.
+      
+      The tIME chunk itself is also Y2K compliant.  It uses a 2-byte unsigned
+      integer to hold the year, and can hold years as large as 65535.
+
+      zlib, upon which libpng depends, is also Y2K compliant.  It contains
+      no date-related code.
+      
+      
+         Glenn Randers-Pehrson
+         libpng maintainer
+         PNG Development Group

ansi2knr.c

@@ -1,488 +0,0 @@
-/* Copyright (C) 1989, 1991, 1993 Aladdin Enterprises. All rights reserved. */
-
-/* ansi2knr.c */
-/* Convert ANSI function declarations to K&R syntax */
-
-/*
-ansi2knr is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY.  No author or distributor accepts responsibility
-to anyone for the consequences of using it or for whether it serves any
-particular purpose or works at all, unless he says so in writing.  Refer
-to the GNU General Public License for full details.
-
-Everyone is granted permission to copy, modify and redistribute
-ansi2knr, but only under the conditions described in the GNU
-General Public License.  A copy of this license is supposed to have been
-given to you along with ansi2knr so you can know your rights and
-responsibilities.  It should be in a file named COPYING.  Among other
-things, the copyright notice and this notice must be preserved on all
-copies.
-*/
-
-/*
----------- Here is the GNU GPL file COPYING, referred to above ----------
------ These terms do NOT apply to the JPEG software itself; see README ------
-
-		    GHOSTSCRIPT GENERAL PUBLIC LICENSE
-		    (Clarified 11 Feb 1988)
-
- Copyright (C) 1988 Richard M. Stallman
- Everyone is permitted to copy and distribute verbatim copies of this
- license, but changing it is not allowed.  You can also use this wording
- to make the terms for other programs.
-
-  The license agreements of most software companies keep you at the
-mercy of those companies.  By contrast, our general public license is
-intended to give everyone the right to share Ghostscript.  To make sure
-that you get the rights we want you to have, we need to make
-restrictions that forbid anyone to deny you these rights or to ask you
-to surrender the rights.  Hence this license agreement.
-
-  Specifically, we want to make sure that you have the right to give
-away copies of Ghostscript, that you receive source code or else can get
-it if you want it, that you can change Ghostscript or use pieces of it
-in new free programs, and that you know you can do these things.
-
-  To make sure that everyone has such rights, we have to forbid you to
-deprive anyone else of these rights.  For example, if you distribute
-copies of Ghostscript, you must give the recipients all the rights that
-you have.  You must make sure that they, too, receive or can get the
-source code.  And you must tell them their rights.
-
-  Also, for our own protection, we must make certain that everyone finds
-out that there is no warranty for Ghostscript.  If Ghostscript is
-modified by someone else and passed on, we want its recipients to know
-that what they have is not what we distributed, so that any problems
-introduced by others will not reflect on our reputation.
-
-  Therefore we (Richard M. Stallman and the Free Software Foundation,
-Inc.) make the following terms which say what you must do to be allowed
-to distribute or change Ghostscript.
-
-
-			COPYING POLICIES
-
-  1. You may copy and distribute verbatim copies of Ghostscript source
-code as you receive it, in any medium, provided that you conspicuously
-and appropriately publish on each copy a valid copyright and license
-notice "Copyright (C) 1989 Aladdin Enterprises.  All rights reserved.
-Distributed by Free Software Foundation, Inc." (or with whatever year is
-appropriate); keep intact the notices on all files that refer to this
-License Agreement and to the absence of any warranty; and give any other
-recipients of the Ghostscript program a copy of this License Agreement
-along with the program.  You may charge a distribution fee for the
-physical act of transferring a copy.
-
-  2. You may modify your copy or copies of Ghostscript or any portion of
-it, and copy and distribute such modifications under the terms of
-Paragraph 1 above, provided that you also do the following:
-
-    a) cause the modified files to carry prominent notices stating
-    that you changed the files and the date of any change; and
-
-    b) cause the whole of any work that you distribute or publish,
-    that in whole or in part contains or is a derivative of Ghostscript
-    or any part thereof, to be licensed at no charge to all third
-    parties on terms identical to those contained in this License
-    Agreement (except that you may choose to grant more extensive
-    warranty protection to some or all third parties, at your option).
-
-    c) You may charge a distribution fee for the physical act of
-    transferring a copy, and you may at your option offer warranty
-    protection in exchange for a fee.
-
-Mere aggregation of another unrelated program with this program (or its
-derivative) on a volume of a storage or distribution medium does not bring
-the other program under the scope of these terms.
-
-  3. You may copy and distribute Ghostscript (or a portion or derivative
-of it, under Paragraph 2) in object code or executable form under the
-terms of Paragraphs 1 and 2 above provided that you also do one of the
-following:
-
-    a) accompany it with the complete corresponding machine-readable
-    source code, which must be distributed under the terms of
-    Paragraphs 1 and 2 above; or,
-
-    b) accompany it with a written offer, valid for at least three
-    years, to give any third party free (except for a nominal
-    shipping charge) a complete machine-readable copy of the
-    corresponding source code, to be distributed under the terms of
-    Paragraphs 1 and 2 above; or,
-
-    c) accompany it with the information you received as to where the
-    corresponding source code may be obtained.  (This alternative is
-    allowed only for noncommercial distribution and only if you
-    received the program in object code or executable form alone.)
-
-For an executable file, complete source code means all the source code for
-all modules it contains; but, as a special exception, it need not include
-source code for modules which are standard libraries that accompany the
-operating system on which the executable file runs.
-
-  4. You may not copy, sublicense, distribute or transfer Ghostscript
-except as expressly provided under this License Agreement.  Any attempt
-otherwise to copy, sublicense, distribute or transfer Ghostscript is
-void and your rights to use the program under this License agreement
-shall be automatically terminated.  However, parties who have received
-computer software programs from you with this License Agreement will not
-have their licenses terminated so long as such parties remain in full
-compliance.
-
-  5. If you wish to incorporate parts of Ghostscript into other free
-programs whose distribution conditions are different, write to the Free
-Software Foundation at 675 Mass Ave, Cambridge, MA 02139.  We have not
-yet worked out a simple rule that can be stated here, but we will often
-permit this.  We will be guided by the two goals of preserving the free
-status of all derivatives of our free software and of promoting the
-sharing and reuse of software.
-
-Your comments and suggestions about our licensing policies and our
-software are welcome!  Please contact the Free Software Foundation,
-Inc., 675 Mass Ave, Cambridge, MA 02139, or call (617) 876-3296.
-
-		       NO WARRANTY
-
-  BECAUSE GHOSTSCRIPT IS LICENSED FREE OF CHARGE, WE PROVIDE ABSOLUTELY
-NO WARRANTY, TO THE EXTENT PERMITTED BY APPLICABLE STATE LAW.  EXCEPT
-WHEN OTHERWISE STATED IN WRITING, FREE SOFTWARE FOUNDATION, INC, RICHARD
-M. STALLMAN, ALADDIN ENTERPRISES, L. PETER DEUTSCH, AND/OR OTHER PARTIES
-PROVIDE GHOSTSCRIPT "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER
-EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE
-ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF GHOSTSCRIPT IS WITH
-YOU.  SHOULD GHOSTSCRIPT PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
-NECESSARY SERVICING, REPAIR OR CORRECTION.
-
-  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW WILL RICHARD M.
-STALLMAN, THE FREE SOFTWARE FOUNDATION, INC., L. PETER DEUTSCH, ALADDIN
-ENTERPRISES, AND/OR ANY OTHER PARTY WHO MAY MODIFY AND REDISTRIBUTE
-GHOSTSCRIPT AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING
-ANY LOST PROFITS, LOST MONIES, OR OTHER SPECIAL, INCIDENTAL OR
-CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE
-(INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED
-INACCURATE OR LOSSES SUSTAINED BY THIRD PARTIES OR A FAILURE OF THE
-PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS) GHOSTSCRIPT, EVEN IF YOU
-HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, OR FOR ANY CLAIM
-BY ANY OTHER PARTY.
-
--------------------- End of file COPYING ------------------------------
-*/
-
-
-#include <stdio.h>
-#include <ctype.h>
-
-#ifdef BSD
-#include <strings.h>
-#else
-#ifdef VMS
-	extern int strlen(), strncmp();
-#else
-#include <string.h>
-#endif
-#endif
-
-/* malloc and free should be declared in stdlib.h, */
-/* but if you've got a K&R compiler, they probably aren't. */
-#ifdef MSDOS
-#include <malloc.h>
-#else
-#ifdef VMS
-     extern char *malloc();
-     extern void free();
-#else
-     extern char *malloc();
-     extern int free();
-#endif
-#endif
-
-/* Usage:
-	ansi2knr input_file [output_file]
- * If no output_file is supplied, output goes to stdout.
- * There are no error messages.
- *
- * ansi2knr recognizes functions by seeing a non-keyword identifier
- * at the left margin, followed by a left parenthesis,
- * with a right parenthesis as the last character on the line.
- * It will recognize a multi-line header provided that the last character
- * of the last line of the header is a right parenthesis,
- * and no intervening line ends with a left brace or a semicolon.
- * These algorithms ignore whitespace and comments, except that
- * the function name must be the first thing on the line.
- * The following constructs will confuse it:
- *	- Any other construct that starts at the left margin and
- *	    follows the above syntax (such as a macro or function call).
- *	- Macros that tinker with the syntax of the function header.
- */
-
-/* Scanning macros */
-#define isidchar(ch) (isalnum(ch) || (ch) == '_')
-#define isidfirstchar(ch) (isalpha(ch) || (ch) == '_')
-
-/* Forward references */
-char *skipspace();
-int writeblanks();
-int test1();
-int convert1();
-
-/* The main program */
-main(argc, argv)
-    int argc;
-    char *argv[];
-{	FILE *in, *out;
-#define bufsize 5000			/* arbitrary size */
-	char *buf;
-	char *line;
-	switch ( argc )
-	   {
-	default:
-		printf("Usage: ansi2knr input_file [output_file]\n");
-		exit(0);
-	case 2:
-		out = stdout; break;
-	case 3:
-		out = fopen(argv[2], "w");
-		if ( out == NULL )
-		   {	fprintf(stderr, "Cannot open %s\n", argv[2]);
-			exit(1);
-		   }
-	   }
-	in = fopen(argv[1], "r");
-	if ( in == NULL )
-	   {	fprintf(stderr, "Cannot open %s\n", argv[1]);
-		exit(1);
-	   }
-	fprintf(out, "#line 1 \"%s\"\n", argv[1]);
-	buf = malloc(bufsize);
-	line = buf;
-	while ( fgets(line, (unsigned)(buf + bufsize - line), in) != NULL )
-	   {	switch ( test1(buf) )
-		   {
-		case 1:			/* a function */
-			convert1(buf, out);
-			break;
-		case -1:		/* maybe the start of a function */
-			line = buf + strlen(buf);
-			if ( line != buf + (bufsize - 1) ) /* overflow check */
-				continue;
-			/* falls through */
-		default:		/* not a function */
-			fputs(buf, out);
-			break;
-		   }
-		line = buf;
-	   }
-	if ( line != buf ) fputs(buf, out);
-	free(buf);
-	fclose(out);
-	fclose(in);
-	return 0;
-}
-
-/* Skip over space and comments, in either direction. */
-char *
-skipspace(p, dir)
-    register char *p;
-    register int dir;			/* 1 for forward, -1 for backward */
-{	for ( ; ; )
-	   {	while ( isspace(*p) ) p += dir;
-		if ( !(*p == '/' && p[dir] == '*') ) break;
-		p += dir;  p += dir;
-		while ( !(*p == '*' && p[dir] == '/') )
-		   {	if ( *p == 0 ) return p;	/* multi-line comment?? */
-			p += dir;
-		   }
-		p += dir;  p += dir;
-	   }
-	return p;
-}
-
-/*
- * Write blanks over part of a string.
- */
-int
-writeblanks(start, end)
-    char *start;
-    char *end;
-{	char *p;
-	for ( p = start; p < end; p++ ) *p = ' ';
-	return 0;
-}
-
-/*
- * Test whether the string in buf is a function definition.
- * The string may contain and/or end with a newline.
- * Return as follows:
- *	0 - definitely not a function definition;
- *	1 - definitely a function definition;
- *	-1 - may be the beginning of a function definition,
- *		append another line and look again.
- */
-int
-test1(buf)
-    char *buf;
-{	register char *p = buf;
-	char *bend;
-	char *endfn;
-	int contin;
-	if ( !isidfirstchar(*p) )
-		return 0;		/* no name at left margin */
-	bend = skipspace(buf + strlen(buf) - 1, -1);
-	switch ( *bend )
-	   {
-	case ')': contin = 1; break;
-	case '{':
-	case ';': return 0;		/* not a function */
-	default: contin = -1;
-	   }
-	while ( isidchar(*p) ) p++;
-	endfn = p;
-	p = skipspace(p, 1);
-	if ( *p++ != '(' )
-		return 0;		/* not a function */
-	p = skipspace(p, 1);
-	if ( *p == ')' )
-		return 0;		/* no parameters */
-	/* Check that the apparent function name isn't a keyword. */
-	/* We only need to check for keywords that could be followed */
-	/* by a left parenthesis (which, unfortunately, is most of them). */
-	   {	static char *words[] =
-		   {	"asm", "auto", "case", "char", "const", "double",
-			"extern", "float", "for", "if", "int", "long",
-			"register", "return", "short", "signed", "sizeof",
-			"static", "switch", "typedef", "unsigned",
-			"void", "volatile", "while", 0
-		   };
-		char **key = words;
-		char *kp;
-		int len = endfn - buf;
-		while ( (kp = *key) != 0 )
-		   {	if ( strlen(kp) == len && !strncmp(kp, buf, len) )
-				return 0;	/* name is a keyword */
-			key++;
-		   }
-	   }
-	return contin;
-}
-
-int
-convert1(buf, out)
-    char *buf;
-    FILE *out;
-{	char *endfn;
-	register char *p;
-	char **breaks;
-	unsigned num_breaks = 2;	/* for testing */
-	char **btop;
-	char **bp;
-	char **ap;
-	/* Pre-ANSI implementations don't agree on whether strchr */
-	/* is called strchr or index, so we open-code it here. */
-	for ( endfn = buf; *(endfn++) != '('; ) ;
-top:	p = endfn;
-	breaks = (char **)malloc(sizeof(char *) * num_breaks * 2);
-	if ( breaks == 0 )
-	   {	/* Couldn't allocate break table, give up */
-		fprintf(stderr, "Unable to allocate break table!\n");
-		fputs(buf, out);
-		return -1;
-	   }
-	btop = breaks + num_breaks * 2 - 2;
-	bp = breaks;
-	/* Parse the argument list */
-	do
-	   {	int level = 0;
-		char *end = NULL;
-		if ( bp >= btop )
-		   {	/* Filled up break table. */
-			/* Allocate a bigger one and start over. */
-			free((char *)breaks);
-			num_breaks <<= 1;
-			goto top;
-		   }
-		*bp++ = p;
-		/* Find the end of the argument */
-		for ( ; end == NULL; p++ )
-		   {	switch(*p)
-			   {
-			case ',': if ( !level ) end = p; break;
-			case '(': level++; break;
-			case ')': if ( --level < 0 ) end = p; break;
-			case '/': p = skipspace(p, 1) - 1; break;
-			default: ;
-			   }
-		   }
-		p--;			/* back up over terminator */
-		/* Find the name being declared. */
-		/* This is complicated because of procedure and */
-		/* array modifiers. */
-		for ( ; ; )
-		   {	p = skipspace(p - 1, -1);
-			switch ( *p )
-			   {
-			case ']':	/* skip array dimension(s) */
-			case ')':	/* skip procedure args OR name */
-			   {	int level = 1;
-				while ( level )
-				 switch ( *--p )
-				   {
-				case ']': case ')': level++; break;
-				case '[': case '(': level--; break;
-				case '/': p = skipspace(p, -1) + 1; break;
-				default: ;
-				   }
-			   }
-				if ( *p == '(' && *skipspace(p + 1, 1) == '*' )
-				   {	/* We found the name being declared */
-					while ( !isidfirstchar(*p) )
-						p = skipspace(p, 1) + 1;
-					goto found;
-				   }
-				break;
-			default: goto found;
-			   }
-		   }
-found:		if ( *p == '.' && p[-1] == '.' && p[-2] == '.' )
-		   {	p++;
-			if ( bp == breaks + 1 )	/* sole argument */
-				writeblanks(breaks[0], p);
-			else
-				writeblanks(bp[-1] - 1, p);
-			bp--;
-		   }
-		else
-		   {	while ( isidchar(*p) ) p--;
-			*bp++ = p+1;
-		   }
-		p = end;
-	   }
-	while ( *p++ == ',' );
-	*bp = p;
-	/* Make a special check for 'void' arglist */
-	if ( bp == breaks+2 )
-	   {	p = skipspace(breaks[0], 1);
-		if ( !strncmp(p, "void", 4) )
-		   {	p = skipspace(p+4, 1);
-			if ( p == breaks[2] - 1 )
-			   {	bp = breaks;	/* yup, pretend arglist is empty */
-				writeblanks(breaks[0], p + 1);
-			   }
-		   }
-	   }
-	/* Put out the function name */
-	p = buf;
-	while ( p != endfn ) putc(*p, out), p++;
-	/* Put out the declaration */
-	for ( ap = breaks+1; ap < bp; ap += 2 )
-	   {	p = *ap;
-		while ( isidchar(*p) ) putc(*p, out), p++;
-		if ( ap < bp - 1 ) fputs(", ", out);
-	   }
-	fputs(")  ", out);
-	/* Put out the argument declarations */
-	for ( ap = breaks+2; ap <= bp; ap += 2 ) (*ap)[-1] = ';';
-	fputs(breaks[0], out);
-	free((char *)breaks);
-	return 0;
-}

example.c

@@ -1,76 +1,114 @@
+
 /* example.c - an example of using libpng */
 
-/* this is an example of how to use libpng to read and write
-   png files.  The file libpng.txt is much more verbose then
-   this.  If you have not read it, do so first.  This was
-   designed to be a starting point of an implementation.
-   This is not officially part of libpng, and therefore
-   does not require a copyright notice.
+/* This is an example of how to use libpng to read and write PNG files.
+ * The file libpng.txt is much more verbose then this.  If you have not
+ * read it, do so first.  This was designed to be a starting point of an
+ * implementation.  This is not officially part of libpng, and therefore
+ * does not require a copyright notice.
+ *
+ * This file does not currently compile, because it is missing certain
+ * parts, like allocating memory to hold an image.  You will have to
+ * supply these parts to get it to compile.  For an example of a minimal
+ * working PNG reader/writer, see pngtest.c, included in this distribution.
+ */
 
-   This file does not currently compile, because it is missing
-   certain parts, like allocating memory to hold an image.
-   You will have to supply these parts to get it to compile.
-   */
+#include "png.h"
 
-#include <png.h>
-
-/* check to see if a file is a png file using png_check_sig() */
-int check_png(char * file_name)
+/* Check to see if a file is a PNG file using png_sig_cmp().  png_sig_cmp()
+ * returns zero if the image is a PNG and nonzero if it isn't a PNG.
+ *
+ * The function check_if_png() shown here, but not used, returns nonzero (true)
+ * if the file can be opened and is a PNG, 0 (false) otherwise.
+ *
+ * If this call is successful, and you are going to keep the file open,
+ * you should call png_set_sig_bytes(png_ptr, PNG_BYTES_TO_CHECK); once
+ * you have created the png_ptr, so that libpng knows your application
+ * has read that many bytes from the start of the file.  Make sure you
+ * don't call png_set_sig_bytes() with more than 8 bytes read or give it
+ * an incorrect number of bytes read, or you will either have read too
+ * many bytes (your fault), or you are telling libpng to read the wrong
+ * number of magic bytes (also your fault).
+ *
+ * Many applications already read the first 2 or 4 bytes from the start
+ * of the image to determine the file type, so it would be easiest just
+ * to pass the bytes to png_sig_cmp() or even skip that if you know
+ * you have a PNG file, and call png_set_sig_bytes().
+ */
+#define PNG_BYTES_TO_CHECK 4
+int check_if_png(char *file_name, FILE **fp)
 {
-   FILE *fp;
-   char buf[8];
-   int ret;
+   char buf[PNG_BYTES_TO_CHECK];
 
-   fp = fopen(file_name, "rb");
-   if (!fp)
-      return 0;
-   ret = fread(buf, 1, 8, fp);
-   fclose(fp);
-
-   if (ret != 8)
+   /* Open the prospective PNG file. */
+   if ((*fp = fopen(file_name, "rb")) != NULL);
       return 0;
 
-   ret = png_check_sig(buf, 8);
+   /* Read in some of the signature bytes */
+   if (fread(buf, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK)
+      return 0;
 
-   return (ret);
+   /* Compare the first PNG_BYTES_TO_CHECK bytes of the signature.
+      Return nonzero (true) if they match */
+
+   return(!png_sig_cmp(buf, (png_size_t)0, PNG_BYTES_TO_CHECK));
 }
 
-/* read a png file.  You may want to return an error code if the read
-   fails (depending upon the failure). */
-void read_png(char *file_name)
+/* Read a PNG file.  You may want to return an error code if the read
+ * fails (depending upon the failure).  There are two "prototypes" given
+ * here - one where we are given the filename, and we need to open the
+ * file, and the other where we are given an open file (possibly with
+ * some or all of the magic bytes read - see comments above).
+ */
+#ifdef open_file /* prototype 1 */
+void read_png(char *file_name)  /* We need to open the file */
 {
-   FILE *fp;
    png_structp png_ptr;
    png_infop info_ptr;
+   unsigned int sig_read = 0;
+   png_uint_32 width, height;
+   int bit_depth, color_type, interlace_type;
+   FILE *fp;
 
-   /* open the file */
-   fp = fopen(file_name, "rb");
-   if (!fp)
+   if ((fp = fopen(file_name, "rb")) == NULL)
       return;
+#else no_open_file /* prototype 2 */
+void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
+{
+   png_structp png_ptr;
+   png_infop info_ptr;
+   png_uint_32 width, height;
+   int bit_depth, color_type, interlace_type;
+#endif no_open_file /* only use one prototype! */
 
    /* Create and initialize the png_struct with the desired error handler
-      functions.  If you want to use the default stderr and longjump method,
-      you can supply NULL for the last three parameters.  We also check that
-      the header file is compatible with the library version.
+    * functions.  If you want to use the default stderr and longjump method,
+    * you can supply NULL for the last three parameters.  We also supply the
+    * the compiler header file version, so that we know if the application
+    * was compiled with a compatible version of the library.  REQUIRED
     */
    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
-      (void *)user_error_ptr, user_error_fn, user_warning_fn);
+      png_voidp user_error_ptr, user_error_fn, user_warning_fn);
 
-   if (!png_ptr)
+   if (png_ptr == NULL)
    {
       fclose(fp);
       return;
    }
 
-   info_ptr = png_create_info_struct();
-   if (!info_ptr)
+   /* Allocate/initialize the memory for image information.  REQUIRED. */
+   info_ptr = png_create_info_struct(png_ptr);
+   if (info_ptr == NULL)
    {
       fclose(fp);
-      png_destroy_read_struct(&png_ptr,  (png_infopp)NULL, (png_infopp)NULL);
+      png_destroy_read_struct(&png_ptr, (png_infopp)NULL, (png_infopp)NULL);
       return;
    }
 
-   /* set error handling if you are using the setjmp/longjmp method */
+   /* Set error handling if you are using the setjmp/longjmp method (this is
+    * the normal method of doing things with libpng).  REQUIRED unless you
+    * set up your own error handlers in the png_create_read_struct() earlier.
+    */
    if (setjmp(png_ptr->jmpbuf))
    {
       /* Free all of the memory associated with the png_ptr and info_ptr */
@@ -80,145 +118,237 @@ void read_png(char *file_name)
       return;
    }
 
-   /* set up the input control if you are using standard C streams */
+   /* One of the following I/O initialization methods is REQUIRED */
+#ifdef streams /* PNG file I/O method 1 */
+   /* Set up the input control if you are using standard C streams */
    png_init_io(png_ptr, fp);
 
-   /* if you are using replacement read functions, instead of calling
-      png_init_io() here you would call */
+#else no_streams /* PNG file I/O method 2 */
+   /* If you are using replacement read functions, instead of calling
+    * png_init_io() here you would call:
+    */
    png_set_read_fn(png_ptr, (void *)user_io_ptr, user_read_fn);
    /* where user_io_ptr is a structure you want available to the callbacks */
+#endif no_streams /* Use only one I/O method! */
 
-   /* read the file information */
+   /* If we have already read some of the signature */
+   png_set_sig_bytes(png_ptr, sig_read);
+
+   /* The call to png_read_info() gives us all of the information from the
+    * PNG file before the first IDAT (image data chunk).  REQUIRED
+    */
    png_read_info(png_ptr, info_ptr);
 
-   /* set up the transformations you want.  Note that these are
-      all optional.  Only call them if you want them */
+   png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+       &interlace_type, NULL, NULL);
 
-   /* expand paletted colors into true RGB triplets */
-   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+/**** Set up the data transformations you want.  Note that these are all
+ **** optional.  Only call them if you want/need them.  Many of the
+ **** transformations only work on specific types of images, and many
+ **** are mutually exclusive.
+ ****/
+
+   /* tell libpng to strip 16 bit/color files down to 8 bits/color */
+   png_set_strip_16(png_ptr);
+
+   /* Strip alpha bytes from the input data without combining with the
+    * background (not recommended).
+    */
+   png_set_strip_alpha(png_ptr);
+
+   /* Extract multiple pixels with bit depths of 1, 2, and 4 from a single
+    * byte into separate bytes (useful for paletted and grayscale images).
+    */
+   png_set_packing(png_ptr);
+
+   /* Change the order of packed pixels to least significant bit first
+    * (not useful if you are using png_set_packing). */
+   png_set_packswap(png_ptr);
+
+   /* Expand paletted colors into true RGB triplets */
+   if (color_type == PNG_COLOR_TYPE_PALETTE)
       png_set_expand(png_ptr);
 
-   /* expand grayscale images to the full 8 bits */
-   if (info_ptr->color_type == PNG_COLOR_TYPE_GRAY && info_ptr->bit_depth < 8)
+   /* Expand grayscale images to the full 8 bits from 1, 2, or 4 bits/pixel */
+   if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
       png_set_expand(png_ptr);
 
-   /* expand paletted or RGB images with transparency to full alpha channels
-    * so the data will be available as RGBA quartets */
-   if (info_ptr->valid & PNG_INFO_tRNS)
+   /* 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))
       png_set_expand(png_ptr);
 
-   /* Set the background color to draw transparent and alpha
-      images over.  It is possible to set the red, green, and blue
-      components directly for paletted images. */
+   /* Set the background color to draw transparent and alpha images over.
+    * It is possible to set the red, green, and blue components directly
+    * for paletted images instead of supplying a palette index.  Note that
+    * even if the PNG file supplies a background, you are not required to
+    * use it - you should use the (solid) application background if it has one.
+    */
 
-   png_color_16 my_background;
+   png_color_16 my_background, *image_background;
 
-   if (info_ptr->valid & PNG_INFO_bKGD)
-      png_set_background(png_ptr, &(info_ptr->background),
+   if (png_get_bKGD(png_ptr, info_ptr, &image_background))
+      png_set_background(png_ptr, image_background,
                          PNG_BACKGROUND_GAMMA_FILE, 1, 1.0);
    else
       png_set_background(png_ptr, &my_background,
                          PNG_BACKGROUND_GAMMA_SCREEN, 0, 1.0);
 
-   /* tell libpng to handle the gamma conversion for you */
-   if (info_ptr->valid & PNG_INFO_gAMA)
-      png_set_gamma(png_ptr, screen_gamma, info_ptr->gamma);
-   else
-      png_set_gamma(png_ptr, screen_gamma, 0.45);
+   /* Some suggestions as to how to get a screen gamma value */
 
-   /* tell libpng to strip 16 bit/color files down to 8 bits/color */
-   if (info_ptr->bit_depth == 16)
-      png_set_strip_16(png_ptr);
-
-   /* dither rgb files down to 8 bit palette & reduce palettes
-      to the number of colors available on your screen */
-   if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+   /* Note that screen gamma is (display_gamma/viewing_gamma) */
+   if (/* We have a user-defined screen gamma value */)
    {
-      if (info_ptr->valid & PNG_INFO_PLTE)
-         png_set_dither(png_ptr, info_ptr->palette, info_ptr->num_palette,
-                        max_screen_colors, info_ptr->histogram);
+      screen_gamma = user-defined screen_gamma;
+   }
+   /* This is one way that applications share the same screen gamma value */
+   else if ((gamma_str = getenv("SCREEN_GAMMA")) != NULL)
+   {
+      screen_gamma = atof(gamma_str);
+   }
+   /* If we don't have another value */
+   else
+   {
+      screen_gamma = 2.2;  /* A good guess for a PC monitors in a dimly
+                              lit room */
+      screen_gamma = 1.7 or 1.0;  /* A good guess for Mac systems */
+   }
+
+   /* Tell libpng to handle the gamma conversion for you.  The second call
+    * is a good guess for PC generated images, but it should be configurable
+    * by the user at run time by the user.  It is strongly suggested that
+    * your application support gamma correction.
+    */
+
+   int intent;
+
+   if (png_get_sRGB(png_ptr, info_ptr, &intent))
+      png_set_sRGB(png_ptr, intent, 0);
+   else
+   {
+      double image_gamma;
+      if (png_get_gAMA(png_ptr, info_ptr, &image_gamma))
+         png_set_gamma(png_ptr, screen_gamma, image_gamma);
       else
+         png_set_gamma(png_ptr, screen_gamma, 0.45455);
+   }
+
+   /* Dither 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)
+   {
+      png_uint_32 num_palette;
+      png_colorp palette;
+
+      /* This reduces the image to the application supplied palette */
+      if (/* we have our own palette */)
       {
-         png_color std_color_cube[MAX_SCREEN_COLORS] =
-            {/* ... colors ... */};
+         /* An array of colors to which the image should be dithered */
+         png_color std_color_cube[MAX_SCREEN_COLORS];
 
          png_set_dither(png_ptr, std_color_cube, MAX_SCREEN_COLORS,
-            MAX_SCREEN_COLORS, NULL);
+            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))
+      {
+         png_color16p histogram;
+
+         png_get_hIST(png_ptr, info_ptr, &histogram);
+
+         png_set_dither(png_ptr, palette, num_palette,
+                        max_screen_colors, histogram, 0);
       }
    }
 
    /* invert monocrome files to have 0 as white and 1 as black */
-   if (info_ptr->bit_depth == 1 && info_ptr->color_type == PNG_COLOR_GRAY)
-      png_set_invert(png_ptr);
+   png_set_invert_mono(png_ptr);
 
-   /* shift the pixels down to their true bit depth */
-   if (info_ptr->valid & PNG_INFO_sBIT &&
-      info_ptr->bit_depth > info_ptr->sig_bit)
-      png_set_shift(png_ptr, &(info_ptr->sig_bit));
+   /* If you want to shift the pixel values from the range [0,255] or
+    * [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))
+   {
+      png_color8p sig_bit;
 
-   /* pack multiple pixels with bit depths of 1, 2, and 4 into bytes
-      (useful only for paletted and grayscale images) */
-   if (info_ptr->bit_depth < 8)
-      png_set_packing(png_ptr);
+      png_get_sBIT(png_ptr, info_ptr, &sig_bit);
+      png_set_shift(png_ptr, sig_bit);
+   }
 
-   /* flip the rgb pixels to bgr */
-   if (info_ptr->color_type == PNG_COLOR_TYPE_RGB ||
-      info_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
-      png_set_bgr(png_ptr);
+   /* flip the RGB pixels to BGR (or RGBA to BGRA) */
+   png_set_bgr(png_ptr);
 
-   /* swap bytes of 16 bit files to least significant bit first */
-   if (info_ptr->bit_depth == 16)
-      png_set_swap(png_ptr);
+   /* swap the RGBA or GA data to ARGB or AG (or BGRA to ABGR) */
+   png_set_swap_alpha(png_ptr);
 
-   /* add a filler byte to RGB files (before or after each RGB triplet) */
-   if (info_ptr->bit_depth == 8 && info_ptr->color_type == PNG_COLOR_TYPE_RGB)
-      png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
+   /* swap bytes of 16 bit files to least significant byte first */
+   png_set_swap(png_ptr);
 
-   /* turn on interlace handling if you are not using png_read_image() */
+   /* Add filler (or alpha) byte (before/after each RGB triplet) */
+   png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
+
+   /* Turn on interlace handling.  REQUIRED if you are not using
+    * png_read_image().  To see how to handle interlacing passes,
+    * see the png_read_row() method below:
+    */
    number_passes = png_set_interlace_handling(png_ptr);
 
-   /* optional call to gamma correct and add the background to the palette
-      and update info structure. */
+   /* Optional call to gamma correct and add the background to the palette
+    * and update info structure.  REQUIRED if you are expecting libpng to
+    * update the palette for you (ie you selected such a transform above).
+    */
    png_read_update_info(png_ptr, info_ptr);
 
-   /* allocate the memory to hold the image using the fields
-      of png_info. */
+   /* Allocate the memory to hold the image using the fields of info_ptr. */
 
-   /* the easiest way to read the image */
+   /* The easiest way to read the image: */
    png_bytep row_pointers[height];
 
    for (row = 0; row < height; row++)
    {
-     row_pointers[row] = malloc(info_ptr->rowbytes);
+      row_pointers[row] = malloc(png_get_rowbytes(png_ptr, info_ptr));
    }
 
+   /* Now it's time to read the image.  One of these methods is REQUIRED */
+#ifdef entire /* Read the entire image in one go */
    png_read_image(png_ptr, row_pointers);
 
-   /* the other way to read images - deal with interlacing */
+#else no_entire /* Read the image one or more scanlines at a time */
+   /* The other way to read images - deal with interlacing: */
 
    for (pass = 0; pass < number_passes; pass++)
    {
-      /* Read the image using the "sparkle" effect. */
-      png_read_rows(png_ptr, row_pointers, NULL, number_of_rows);
-
-      /* If you are only reading on row at a time, this works */
+#ifdef single /* Read the image a single row at a time */
       for (y = 0; y < height; y++)
       {
-         png_bytep row_pointers = row[y];
-         png_read_rows(png_ptr, &row_pointers, NULL, 1);
+         png_read_rows(png_ptr, &row_pointers[y], NULL, 1);
       }
 
-      /* to get the rectangle effect, use the third parameter */
-      png_read_rows(png_ptr, NULL, row_pointers, number_of_rows);
+#else no_single /* Read the image several rows at a time */
+      for (y = 0; y < height; y += number_of_rows)
+      {
+#ifdef sparkle /* Read the image using the "sparkle" effect. */
+         png_read_rows(png_ptr, &row_pointers[y], NULL, number_of_rows);
+
+         png_read_rows(png_ptr, NULL, row_pointers[y], number_of_rows);
+#else no_sparkle /* Read the image using the "rectangle" effect */
+         png_read_rows(png_ptr, NULL, &row_pointers[y], number_of_rows);
+#endif no_sparkle /* use only one of these two methods */
+      }
 
       /* if you want to display the image after every pass, do
          so here */
+#endif no_single /* use only one of these two methods */
    }
+#endif no_entire /* use only one of these two methods */
 
-   /* read the rest of the file, getting any additional chunks in info_ptr */
+   /* read rest of file, and get additional chunks in info_ptr - REQUIRED */
    png_read_end(png_ptr, info_ptr);
 
-   /* clean up after the read, and free any memory allocated */
+   /* clean up after the read, and free any memory allocated - REQUIRED */
    png_destroy_read_struct(&png_ptr, &info_ptr, (png_infopp)NULL);
 
    /* close the file */
@@ -234,15 +364,15 @@ int
 initialize_png_reader(png_structp *png_ptr, png_infop *info_ptr)
 {
    /* Create and initialize the png_struct with the desired error handler
-      functions.  If you want to use the default stderr and longjump method,
-      you can supply NULL for the last three parameters.  We also check that
-      the library version is compatible in case we are using dynamically
-      linked libraries.
+    * functions.  If you want to use the default stderr and longjump method,
+    * you can supply NULL for the last three parameters.  We also check that
+    * the library version is compatible in case we are using dynamically
+    * linked libraries.
     */
    *png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING,
-       (void *)user_error_ptr, user_error_fn, user_warning_fn);
+       png_voidp user_error_ptr, user_error_fn, user_warning_fn);
 
-   if (! *png_ptr)
+   if (*png_ptr == NULL)
    {
       *info_ptr = NULL;
       return ERROR;
@@ -250,7 +380,7 @@ initialize_png_reader(png_structp *png_ptr, png_infop *info_ptr)
 
    *info_ptr = png_create_info_struct(png_ptr);
 
-   if (! *info_ptr)
+   if (*info_ptr == NULL)
    {
       png_destroy_read_struct(png_ptr, info_ptr, (png_infopp)NULL);
       return ERROR;
@@ -262,14 +392,18 @@ initialize_png_reader(png_structp *png_ptr, png_infop *info_ptr)
       return ERROR;
    }
 
-   /* this one's new.  You will need to provide all three
-      function callbacks, even if you aren't using them all.
-      These functions shouldn't be dependent on global or
-      static variables if you are decoding several images
-      simultaneously.  You should store stream specific data
-      in a separate struct, given as the second parameter,
-      and retrieve the pointer from inside the callbacks using
-      the function png_get_progressive_ptr(png_ptr). */
+   /* This one's new.  You will need to provide all three
+    * function callbacks, even if you aren't using them all.
+    * If you aren't using all functions, you can specify NULL
+    * parameters.  Even when all three functions are NULL,
+    * you need to call png_set_progressive_read_fn().
+    * These functions shouldn't be dependent on global or
+    * static variables if you are decoding several images
+    * simultaneously.  You should store stream specific data
+    * in a separate struct, given as the second parameter,
+    * and retrieve the pointer from inside the callbacks using
+    * the function png_get_progressive_ptr(png_ptr).
+    */
    png_set_progressive_read_fn(*png_ptr, (void *)stream_data,
       info_callback, row_callback, end_callback);
 
@@ -287,15 +421,16 @@ process_data(png_structp *png_ptr, png_infop *info_ptr,
       return ERROR;
    }
 
-   /* this one's new also.  Simply give it chunks of data as
-      they arrive from the data stream (in order, of course).
-      On Segmented machines, don't give it any more than 64K.
-      The library seems to run fine with sizes of 4K, although
-      you can give it much less if necessary (I assume you can
-      give it chunks of 1 byte, but I haven't tried with less
-      than 256 bytes yet).  When this function returns, you may
-      want to display any rows that were generated in the row
-      callback, if you aren't already displaying them there. */
+   /* This one's new also.  Simply give it chunks of data as
+    * they arrive from the data stream (in order, of course).
+    * On Segmented machines, don't give it any more than 64K.
+    * The library seems to run fine with sizes of 4K, although
+    * you can give it much less if necessary (I assume you can
+    * give it chunks of 1 byte, but I haven't tried with less
+    * than 256 bytes yet).  When this function returns, you may
+    * want to display any rows that were generated in the row
+    * callback, if you aren't already displaying them there.
+    */
    png_process_data(*png_ptr, *info_ptr, buffer, length);
    return OK;
 }
@@ -303,56 +438,60 @@ process_data(png_structp *png_ptr, png_infop *info_ptr,
 info_callback(png_structp png_ptr, png_infop info)
 {
 /* do any setup here, including setting any of the transformations
-   mentioned in the Reading PNG files section.  For now, you _must_
-   call either png_start_read_image() or png_read_update_info()
-   after all the transformations are set (even if you don't set
-   any).  You may start getting rows before png_process_data()
-   returns, so this is your last chance to prepare for that. */
+ * mentioned in the Reading PNG files section.  For now, you _must_
+ * call either png_start_read_image() or png_read_update_info()
+ * after all the transformations are set (even if you don't set
+ * any).  You may start getting rows before png_process_data()
+ * returns, so this is your last chance to prepare for that.
+ */
 }
 
 row_callback(png_structp png_ptr, png_bytep new_row,
    png_uint_32 row_num, int pass)
 {
 /* this function is called for every row in the image.  If the
-   image is interlacing, and you turned on the interlace handler,
-   this function will be called for every row in every pass.
-   Some of these rows will not be changed from the previous pass.
-   When the row is not changed, the new_row variable will be NULL.
-   The rows and passes are called in order, so you don't really
-   need the row_num and pass, but I'm supplying them because it
-   may make your life easier.
-
-   For the non-NULL rows of interlaced images, you must call
-   png_progressive_combine_row() passing in the row and the
-   old row.  You can call this function for NULL rows (it will
-   just return) and for non-interlaced images (it just does the
-   memcpy for you) if it will make the code easier.  Thus, you
-   can just do this for all cases: */
+ * image is interlacing, and you turned on the interlace handler,
+ * this function will be called for every row in every pass.
+ * Some of these rows will not be changed from the previous pass.
+ * When the row is not changed, the new_row variable will be NULL.
+ * The rows and passes are called in order, so you don't really
+ * need the row_num and pass, but I'm supplying them because it
+ * may make your life easier.
+ *
+ * For the non-NULL rows of interlaced images, you must call
+ * png_progressive_combine_row() passing in the row and the
+ * old row.  You can call this function for NULL rows (it will
+ * just return) and for non-interlaced images (it just does the
+ * memcpy for you) if it will make the code easier.  Thus, you
+ * can just do this for all cases:
+ */
 
    png_progressive_combine_row(png_ptr, old_row, new_row);
 
 /* where old_row is what was displayed for previous rows.  Note
-   that the first pass (pass == 0 really) will completely cover
-   the old row, so the rows do not have to be initialized.  After
-   the first pass (and only for interlaced images), you will have
-   to pass the current row, and the function will combine the
-   old row and the new row. */
+ * that the first pass (pass == 0 really) will completely cover
+ * the old row, so the rows do not have to be initialized.  After
+ * the first pass (and only for interlaced images), you will have
+ * to pass the current row, and the function will combine the
+ * old row and the new row.
+ */
 }
 
 end_callback(png_structp png_ptr, png_infop info)
 {
 /* this function is called when the whole image has been read,
-   including any chunks after the image (up to and including
-   the IEND).  You will usually have the same info chunk as you
-   had in the header, although some data may have been added
-   to the comments and time fields.
-
-   Most people won't do much here, perhaps setting a flag that
-   marks the image as finished. */
+ * including any chunks after the image (up to and including
+ * the IEND).  You will usually have the same info chunk as you
+ * had in the header, although some data may have been added
+ * to the comments and time fields.
+ *
+ * Most people won't do much here, perhaps setting a flag that
+ * marks the image as finished.
+ */
 }
 
 /* write a png file */
-void write_png(char *file_name, ... other image information ...)
+void write_png(char *file_name /* , ... other image information ... */)
 {
    FILE *fp;
    png_structp png_ptr;
@@ -360,33 +499,36 @@ void write_png(char *file_name, ... other image information ...)
 
    /* open the file */
    fp = fopen(file_name, "wb");
-   if (!fp)
+   if (fp == NULL)
       return;
 
    /* Create and initialize the png_struct with the desired error handler
-      functions.  If you want to use the default stderr and longjump method,
-      you can supply NULL for the last three parameters.  We also check that
-      the library version is compatible in case we are using dynamically
-      linked libraries.
+    * functions.  If you want to use the default stderr and longjump method,
+    * you can supply NULL for the last three parameters.  We also check that
+    * the library version is compatible with the one used at compile time,
+    * in case we are using dynamically linked libraries.  REQUIRED.
     */
    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,
-      (void *)user_error_ptr, user_error_fn, user_warning_fn);
+      png_voidp user_error_ptr, user_error_fn, user_warning_fn);
 
-   if (!png_ptr)
+   if (png_ptr == NULL)
    {
       fclose(fp);
       return;
    }
 
+   /* Allocate/initialize the image information data.  REQUIRED */
    info_ptr = png_create_info_struct(png_ptr);
-   if (!info_ptr)
+   if (info_ptr == NULL)
    {
       fclose(fp);
       png_destroy_write_struct(&png_ptr,  (png_infopp)NULL);
       return;
    }
 
-   /* set error handling */
+   /* Set error handling.  REQUIRED if you aren't supplying your own
+    * error hadnling functions in the png_create_write_struct() call.
+    */
    if (setjmp(png_ptr->jmpbuf))
    {
       /* If we get here, we had a problem reading the file */
@@ -395,67 +537,107 @@ void write_png(char *file_name, ... other image information ...)
       return;
    }
 
+   /* One of the following I/O initialization functions is REQUIRED */
+#ifdef streams /* I/O initialization method 1 */
    /* set up the output control if you are using standard C streams */
    png_init_io(png_ptr, fp);
+#else no_streams /* I/O initialization method 2 */
+   /* If you are using replacement read functions, instead of calling
+    * png_init_io() here you would call */
+   png_set_write_fn(png_ptr, (void *)user_io_ptr, user_write_fn,
+      user_IO_flush_function);
+   /* where user_io_ptr is a structure you want available to the callbacks */
+#endif no_streams /* only use one initialization method */
 
-   /* if you are using replacement message functions, here you would call */
-   png_set_message_fn(png_ptr, (void *)msg_ptr, user_error_fn, user_warning_fn);
-   /* where msg_ptr is a structure you want available to the callbacks */
+   /* Set the image information here.  Width and height are up to 2^31,
+    * bit_depth is one of 1, 2, 4, 8, or 16, but valid values also depend on
+    * the color_type selected. color_type is one of PNG_COLOR_TYPE_GRAY,
+    * PNG_COLOR_TYPE_GRAY_ALPHA, PNG_COLOR_TYPE_PALETTE, PNG_COLOR_TYPE_RGB,
+    * or PNG_COLOR_TYPE_RGB_ALPHA.  interlace is either PNG_INTERLACE_NONE or
+    * PNG_INTERLACE_ADAM7, and the compression_type and filter_type MUST
+    * currently be PNG_COMPRESSION_TYPE_BASE and PNG_FILTER_TYPE_BASE. REQUIRED
+    */
+   png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth, PNG_COLOR_TYPE_???,
+      PNG_INTERLACE_????, PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
 
-   /* set the file information here */
-   info_ptr->width = ;
-   info_ptr->height = ;
-   etc.
-
-   /* set the palette if there is one */
-   info_ptr->valid |= PNG_INFO_PLTE;
-   info_ptr->palette = malloc(256 * sizeof (png_color));
-   info_ptr->num_palette = 256;
-   ... set palette colors ...
+   /* set the palette if there is one.  REQUIRED for indexed-color images */
+   palette = (png_colorp)png_malloc(png_ptr, 256 * sizeof (png_color));
+   /* ... set palette colors ... */
+   png_set_PLTE(png_ptr, info_ptr, palette, 256);
 
    /* optional significant bit chunk */
-   info_ptr->valid |= PNG_INFO_sBIT;
    /* if we are dealing with a grayscale image then */
-   info_ptr->sig_bit.gray = true_bit_depth;
+   sig_bit.gray = true_bit_depth;
    /* otherwise, if we are dealing with a color image then */
-   info_ptr->sig_bit.red = true_red_bit_depth;
-   info_ptr->sig_bit.green = true_green_bit_depth;
-   info_ptr->sig_bit.blue = true_blue_bit_depth;
+   sig_bit.red = true_red_bit_depth;
+   sig_bit.green = true_green_bit_depth;
+   sig_bit.blue = true_blue_bit_depth;
    /* if the image has an alpha channel then */
-   info_ptr->sig_bit.alpha = true_alpha_bit_depth;
-  
-   /* optional gamma chunk is strongly suggested if you have any guess
-      as to the correct gamma of the image */
-   info_ptr->valid |= PNG_INFO_gAMA;
-   info_ptr->gamma = gamma;
+   sig_bit.alpha = true_alpha_bit_depth;
+   png_set_sBIT(png_ptr, info_ptr, sig_bit);
 
-   /* other optional chunks like cHRM, bKGD, tRNS, tEXt, tIME, oFFs, pHYs, */
 
-   /* write the file header information */
+   /* Optional gamma chunk is strongly suggested if you have any guess
+    * as to the correct gamma of the image.
+    */
+   png_set_gAMA(png_ptr, info_ptr, gamma);
+
+   /* Optionally write comments into the image */
+   text_ptr[0].key = "Title";
+   text_ptr[0].text = "Mona Lisa";
+   text_ptr[0].compression = PNG_TEXT_COMPRESSION_NONE;
+   text_ptr[1].key = "Author";
+   text_ptr[1].text = "Leonardo DaVinci";
+   text_ptr[1].compression = PNG_TEXT_COMPRESSION_NONE;
+   text_ptr[2].key = "Description";
+   text_ptr[2].text = "<long text>";
+   text_ptr[2].compression = PNG_TEXT_COMPRESSION_zTXt;
+   png_set_text(png_ptr, info_ptr, text_ptr, 3);
+
+   /* other optional chunks like cHRM, bKGD, tRNS, tIME, oFFs, pHYs, */
+   /* note that if sRGB is present the cHRM chunk must be ignored
+    * on read and must be written in accordance with the sRGB profile */
+
+   /* Write the file header information.  REQUIRED */
    png_write_info(png_ptr, info_ptr);
 
+   /* Once we write out the header, the compression type on the text
+    * chunks gets changed to PNG_TEXT_COMPRESSION_NONE_WR or
+    * PNG_TEXT_COMPRESSION_zTXt_WR, so it doesn't get written out again
+    * at the end.
+    */
+
    /* set up the transformations you want.  Note that these are
-      all optional.  Only call them if you want them */
+    * all optional.  Only call them if you want them.
+    */
 
    /* invert monocrome pixels */
-   png_set_invert(png_ptr);
+   png_set_invert_mono(png_ptr);
 
-   /* shift the pixels up to a legal bit depth and fill in
-      as appropriate to correctly scale the image */
-   png_set_shift(png_ptr, &(info_ptr->sig_bit));
+   /* Shift the pixels up to a legal bit depth and fill in
+    * as appropriate to correctly scale the image.
+    */
+   png_set_shift(png_ptr, &sig_bit);
 
    /* pack pixels into bytes */
    png_set_packing(png_ptr);
 
-   /* flip bgr pixels to rgb */
+   /* swap location of alpha bytes from ARGB to RGBA */
+   png_set_swap_alpha(png_ptr);
+
+   /* Get rid of filler (OR ALPHA) bytes, pack XRGB/RGBX/ARGB/RGBA into
+    * RGB (4 channels -> 3 channels). The second parameter is not used.
+    */
+   png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+
+   /* flip BGR pixels to RGB */
    png_set_bgr(png_ptr);
 
-   /* swap bytes of 16 bit files to most significant bit first */
+   /* swap bytes of 16-bit files to most significant byte first */
    png_set_swap(png_ptr);
 
-   /* get rid of filler bytes, pack rgb into 3 bytes.  The
-      filler number is not used. */
-   png_set_filler(png_ptr, 0, PNG_FILLER_BEFORE);
+   /* swap bits of 1, 2, 4 bit packed pixel formats */
+   png_set_packswap(png_ptr);
 
    /* turn on interlace handling if you are not using png_write_image() */
    if (interlacing)
@@ -463,44 +645,53 @@ void write_png(char *file_name, ... other image information ...)
    else
       number_passes = 1;
 
-   /* the easiest way to write the image (you may choose to allocate the
-      memory differently, however) */
-   png_byte row_pointers[height][width];
+   /* The easiest way to write the image (you may have a different memory
+    * layout, however, so choose what fits your needs best).  You need to
+    * use the first method if you aren't handling interlacing yourself.
+    */
+   png_uint_32 k, height, width;
+   png_byte image[height][width];
+   png_bytep row_pointers[height];
+   for (k = 0; k < height; k++)
+     row_pointers[k] = image + k*width;
 
+   /* One of the following output methods is REQUIRED */
+#ifdef entire /* write out the entire image data in one call */
    png_write_image(png_ptr, row_pointers);
 
    /* the other way to write the image - deal with interlacing */
 
+#else no_entire /* write out the image data by one or more scanlines */
+   /* The number of passes is either 1 for non-interlaced images,
+    * or 7 for interlaced images.
+    */
    for (pass = 0; pass < number_passes; pass++)
    {
       /* Write a few rows at a time. */
-      png_write_rows(png_ptr, row_pointers, number_of_rows);
+      png_write_rows(png_ptr, &row_pointers[first_row], number_of_rows);
 
       /* If you are only writing one row at a time, this works */
       for (y = 0; y < height; y++)
       {
-         png_bytep row_pointers = row[y];
-         png_write_rows(png_ptr, &row_pointers, 1);
+         png_write_rows(png_ptr, &row_pointers[y], 1);
       }
    }
+#endif no_entire /* use only one output method */
 
-   /* You can write optional chunks like tEXt, tIME at the end as well.
-    * Note that if you wrote tEXt or zTXt chunks before the image, and
-    * you aren't writing out more at the end, you have to set
-    * info_ptr->num_text = 0 or they will be written out again.
+   /* You can write optional chunks like tEXt, zTXt, and tIME at the end
+    * as well.
     */
 
-   /* write the rest of the file */
+   /* It is REQUIRED to call this to finish writing the rest of the file */
    png_write_end(png_ptr, info_ptr);
 
    /* if you malloced the palette, free it here */
-   if (info_ptr->palette)
-      free(info_ptr->palette);
+   free(info_ptr->palette);
 
    /* if you allocated any text comments, free them here */
 
    /* clean up after the write, and free any memory allocated */
-   png_destroy_write_struct(&png_ptr,  (png_infopp)NULL);
+   png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
 
    /* close the file */
    fclose(fp);

libpngpf.3

@@ -0,0 +1,505 @@
+.TH LIBPNGPF 3 September 19, 1999
+.SH NAME
+libpng \- Portable Network Graphics (PNG) Reference Library 1.0.4 - September 19, 1999
+(private functions)
+.SH SYNOPSIS
+\fB#include <png.h>\fP
+
+\fI\fB
+
+\fBvoid png_build_gamma_table (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_build_grayscale_palette (int \fP\fIbit_depth\fP\fB, png_colorp \fIpalette\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_calculate_crc (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIptr\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_check_chunk_name (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIchunk_name\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_size_t png_check_keyword (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIkey\fP\fB, png_charpp \fInew_key\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_combine_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fImask\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_correct_palette (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fInum_palette\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_crc_error (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_crc_finish (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIskip\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_crc_read (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuf\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_create_struct (int \fP\fItype\fP\fB, png_malloc_ptr \fImalloc_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_voidp png_create_struct_2 (int \fItype\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_struct (png_voidp \fIstruct_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_destroy_struct_2 (png_voidp \fP\fIstruct_ptr\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_background (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_16p \fP\fItrans_values\fP\fB, png_color_16p \fP\fIbackground\fP\fB, png_color_16p \fP\fIbackground_1\fP\fB, png_bytep \fP\fIgamma_table\fP\fB, png_bytep \fP\fIgamma_from_1\fP\fB, png_bytep \fP\fIgamma_to_1\fP\fB, png_uint_16pp \fP\fIgamma_16\fP\fB, png_uint_16pp \fP\fIgamma_16_from_1\fP\fB, png_uint_16pp \fP\fIgamma_16_to_1\fP\fB, int \fIgamma_shift\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_bgr (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_chop (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_dither (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fP\fIpalette_lookup\fP\fB, png_bytep \fIdither_lookup\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_expand (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_16p \fItrans_value\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_expand_palette (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_colorp \fP\fIpalette\fP\fB, png_bytep \fP\fItrans\fP\fB, int \fInum_trans\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_gamma (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fP\fIgamma_table\fP\fB, png_uint_16pp \fP\fIgamma_16_table\fP\fB, int \fIgamma_shift\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_gray_to_rgb (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_invert (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_pack (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_uint_32 \fIbit_depth\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_packswap (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_read_filler (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_uint_32 \fP\fIfiller\fP\fB, png_uint_32 \fIflags\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_read_interlace (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fP\fIpass\fP\fB, png_uint_32 \fItransformations\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_read_invert_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_read_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_read_transformations (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBint png_do_rgb_to_gray (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_shift (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_8p \fIbit_depth\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_strip_filler (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_uint_32 \fIflags\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_swap (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_unpack (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_unshift (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_color_8p \fIsig_bits\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_write_interlace (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fIpass\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_write_invert_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_write_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_do_write_transformations (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid *png_far_to_near (png_structp png_ptr,png_voidp \fP\fIptr\fP\fB, int \fIcheck\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_flush (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_int_32 png_get_int_32 (png_bytep \fIbuf\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_16 png_get_uint_16 (png_bytep \fIbuf\fP\fB);\fP
+
+\fI\fB
+
+\fBpng_uint_32 png_get_uint_32 (png_bytep \fIbuf\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_cHRM (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_gAMA (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_IEND (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_sRGB (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_unknown (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_handle_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_info_destroy (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_init_read_transformations (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_process_IDAT_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIbuffer_length\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_process_some_data (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_check_crc (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_crc_finish (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_crc_skip (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_fill_buffer (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_handle_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_handle_unknown (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_handle_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fP\fIinfo_ptr\fP\fB, png_uint_32 \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_have_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_have_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_have_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIrow\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_process_row (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_read_chunk (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_read_end (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_read_IDAT (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_read_sig (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_read_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_read_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_restore_buffer (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuffer\fP\fB, png_size_t \fIbuffer_length\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_push_save_buffer (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_filter_row (png_structp \fP\fIpng_ptr\fP\fB, png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, png_bytep \fP\fIprev_row\fP\fB, int \fIfilter\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_finish_row (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_init (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_push_finish_row (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_start_row (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_read_transform_info (png_structp \fP\fIpng_ptr\fP\fB, png_infop \fIinfo_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_reset_crc (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_save_int_32 (png_bytep \fP\fIbuf\fP\fB, png_int_32 \fIi\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_save_uint_16 (png_bytep \fP\fIbuf\fP\fB, unsigned int \fIi\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_save_uint_32 (png_bytep \fP\fIbuf\fP\fB, png_uint_32 \fIi\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_bKGD (png_structp \fP\fIpng_ptr\fP\fB, png_color_16p \fP\fIvalues\fP\fB, int \fIcolor_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_cHRM (png_structp \fP\fIpng_ptr\fP\fB, double \fP\fIwhite_x\fP\fB, double \fP\fIwhite_y\fP\fB, double \fP\fIred_x\fP\fB, double \fP\fIred_y\fP\fB, double \fP\fIgreen_x\fP\fB, double \fP\fIgreen_y\fP\fB, double \fP\fIblue_x\fP\fB, double \fIblue_y\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_data (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fBvoid png_write_filtered_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIfiltered_row\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_find_filter (png_structp \fP\fIpng_ptr\fP\fB, png_row_infop \fIrow_info\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_finish_row (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_gAMA (png_structp \fP\fIpng_ptr\fP\fB, double \fIfile_gamma\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_hIST (png_structp \fP\fIpng_ptr\fP\fB, png_uint_16p \fP\fIhist\fP\fB, int \fInum_hist\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_init (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_IDAT (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIdata\fP\fB, png_size_t \fIlength\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_IEND (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_IHDR (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIwidth\fP\fB, png_uint_32 \fP\fIheight\fP\fB, int \fP\fIbit_depth\fP\fB, int \fP\fIcolor_type\fP\fB, int \fP\fIcompression_type\fP\fB, int \fP\fIfilter_type\fP\fB, int \fIinterlace_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_oFFs (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIx_offset\fP\fB, png_uint_32 \fP\fIy_offset\fP\fB, int \fIunit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_pCAL (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIpurpose\fP\fB, png_int_32 \fP\fIX0\fP\fB, png_int_32 \fP\fIX1\fP\fB, int \fP\fItype\fP\fB, int \fP\fInparams\fP\fB, png_charp \fP\fIunits\fP\fB, png_charpp \fIparams\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_pHYs (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fP\fIx_pixels_per_unit\fP\fB, png_uint_32 \fP\fIy_pixels_per_unit\fP\fB, int \fIunit_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_PLTE (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, png_uint_32 \fInum_pal\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_sBIT (png_structp \fP\fIpng_ptr\fP\fB, png_color_8p \fP\fIsbit\fP\fB, int \fIcolor_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_sig (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_sRGB (png_structp \fP\fIpng_ptr\fP\fB, int \fIintent\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_start_row (png_structp \fIpng_ptr\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_tEXt (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIkey\fP\fB, png_charp \fP\fItext\fP\fB, png_size_t \fItext_len\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_tIME (png_structp \fP\fIpng_ptr\fP\fB, png_timep \fImod_time\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_tRNS (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fItrans\fP\fB, png_color_16p \fP\fIvalues\fP\fB, int \fP\fInumber\fP\fB, int \fIcolor_type\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_write_zTXt (png_structp \fP\fIpng_ptr\fP\fB, png_charp \fP\fIkey\fP\fB, png_charp \fP\fItext\fP\fB, png_size_t \fP\fItext_len\fP\fB, int \fIcompression\fP\fB);\fP
+
+\fI\fB
+
+\fBvoidpf png_zalloc (voidpf \fP\fIpng_ptr\fP\fB, uInt \fP\fIitems\fP\fB, uInt \fIsize\fP\fB);\fP
+
+\fI\fB
+
+\fBvoid png_zfree (voidpf \fP\fIpng_ptr\fP\fB, voidpf \fIptr\fP\fB);\fP
+
+\fI\fB
+
+.SH DESCRIPTION
+The functions listed above are used privately by libpng
+and are not recommended for use by applications.  They
+are listed alphabetically here as an aid to libpng maintainers.
+See png.h for more information on these functions.
+
+.SH SEE ALSO
+libpng(3), png(5)
+.SH AUTHOR
+Glenn Randers-Pehrson

makefile.aco

@@ -1,114 +0,0 @@
-# Project:   libpng
-
-
-# Toolflags:
-CCflags = -c -depend !Depend -IC:,Zlib: -g -throwback  -DRISCOS  -fnah 
-C++flags = -c -depend !Depend -IC: -throwback
-Linkflags = -aif -c++ -o $@
-ObjAsmflags = -throwback -NoCache -depend !Depend
-CMHGflags = 
-LibFileflags = -c -o $@ 
-Squeezeflags = -o $@
-
-
-# Final targets:
-@.libpng-lib:   @.o.png @.o.pngerror @.o.pngrio @.o.pngwio @.o.pngmem \
-        @.o.pngpread @.o.pngrcb @.o.pngread @.o.pngrtran @.o.pngrutil \
-        @.o.pngtrans @.o.pngwrite @.o.pngwtran @.o.pngwutil
-        LibFile $(LibFileflags) @.o.png @.o.pngerror @.o.pngrio @.o.pngwio \
-        @.o.pngmem @.o.pngpread @.o.pngrcb @.o.pngread @.o.pngrtran \
-        @.o.pngrutil @.o.pngtrans @.o.pngwrite @.o.pngwtran @.o.pngwutil 
-@.test:   @.tests.pngtest 
-        echo Please run "Test" in directory tests 
-@.tests.pngtest:   @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib 
-        Link $(Linkflags) @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib 
-
-
-# User-editable dependencies:
-.c.o:
-        cc $(ccflags) -o $@ $<
-
-
-# Static dependencies:
-@.o.example:   @.tests.c.example
-        cc $(ccflags) -o @.o.example @.tests.c.example 
-@.o.pngtest:   @.tests.c.pngtest
-        cc $(ccflags) -o @.o.pngtest @.tests.c.pngtest 
-
-
-# Dynamic dependencies:
-o.png:	c.png
-o.png:	h.png
-o.png:	Zlib:h.zlib
-o.png:	Zlib:h.zconf
-o.png:	h.pngconf
-o.pngerror:	c.pngerror
-o.pngerror:	h.png
-o.pngerror:	Zlib:h.zlib
-o.pngerror:	Zlib:h.zconf
-o.pngerror:	h.pngconf
-o.pngrio:	c.pngrio
-o.pngrio:	h.png
-o.pngrio:	Zlib:h.zlib
-o.pngrio:	Zlib:h.zconf
-o.pngrio:	h.pngconf
-o.pngwio:	c.pngwio
-o.pngwio:	h.png
-o.pngwio:	Zlib:h.zlib
-o.pngwio:	Zlib:h.zconf
-o.pngwio:	h.pngconf
-o.pngmem:	c.pngmem
-o.pngmem:	h.png
-o.pngmem:	Zlib:h.zlib
-o.pngmem:	Zlib:h.zconf
-o.pngmem:	h.pngconf
-o.pngpread:	c.pngpread
-o.pngpread:	h.png
-o.pngpread:	Zlib:h.zlib
-o.pngpread:	Zlib:h.zconf
-o.pngpread:	h.pngconf
-o.pngrcb:	c.pngrcb
-o.pngrcb:	h.png
-o.pngrcb:	Zlib:h.zlib
-o.pngrcb:	Zlib:h.zconf
-o.pngrcb:	h.pngconf
-o.pngread:	c.pngread
-o.pngread:	h.png
-o.pngread:	Zlib:h.zlib
-o.pngread:	Zlib:h.zconf
-o.pngread:	h.pngconf
-o.pngrtran:	c.pngrtran
-o.pngrtran:	h.png
-o.pngrtran:	Zlib:h.zlib
-o.pngrtran:	Zlib:h.zconf
-o.pngrtran:	h.pngconf
-o.pngrutil:	c.pngrutil
-o.pngrutil:	h.png
-o.pngrutil:	Zlib:h.zlib
-o.pngrutil:	Zlib:h.zconf
-o.pngrutil:	h.pngconf
-o.pngtrans:	c.pngtrans
-o.pngtrans:	h.png
-o.pngtrans:	Zlib:h.zlib
-o.pngtrans:	Zlib:h.zconf
-o.pngtrans:	h.pngconf
-o.pngwrite:	c.pngwrite
-o.pngwrite:	h.png
-o.pngwrite:	Zlib:h.zlib
-o.pngwrite:	Zlib:h.zconf
-o.pngwrite:	h.pngconf
-o.pngwtran:	c.pngwtran
-o.pngwtran:	h.png
-o.pngwtran:	Zlib:h.zlib
-o.pngwtran:	Zlib:h.zconf
-o.pngwtran:	h.pngconf
-o.pngwutil:	c.pngwutil
-o.pngwutil:	h.png
-o.pngwutil:	Zlib:h.zlib
-o.pngwutil:	Zlib:h.zconf
-o.pngwutil:	h.pngconf
-o.pngtest:	tests.c.pngtest
-o.pngtest:	h.png
-o.pngtest:	Zlib:h.zlib
-o.pngtest:	Zlib:h.zconf
-o.pngtest:	h.pngconf

makefile.elf

@@ -1,74 +0,0 @@
-# makefile for libpng on (linux) ELF
-# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
-# For conditions of distribution and use, see copyright notice in png.h
-
-CC=gcc
-CFLAGS=-I../zlib -O2 -Wall -fPIC
-LDFLAGS=-L. -Wl,-rpath,. -L../zlib/ -Wl,-rpath,../zlib/ -lpng -lz -lm
-
-RANLIB=ranlib
-#RANLIB=echo
-
-PNGVER = 0.89
-
-# where make install puts libpng.a, libpng.so*, and png.h
-prefix=/usr/local
-
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
-       pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
-       pngwtran.o pngmem.o pngerror.o pngpread.o
-
-all: libpng.so pngtest
-
-libpng.a: $(OBJS)
-	ar rc $@  $(OBJS)
-	$(RANLIB) $@
-
-libpng.so: libpng.so.1
-	ln -sf libpng.so.1 libpng.so
-
-libpng.so.1: libpng.so.1.$(PNGVER)
-	ln -sf libpng.so.1.$(PNGVER) libpng.so.1
-
-libpng.so.1.$(PNGVER): $(OBJS)
-	gcc -shared -Wl,-soname,libpng.so.1 -o libpng.so.1.$(PNGVER) $(OBJS)
-
-pngtest: pngtest.o libpng.so
-	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
-
-test: pngtest
-	./pngtest
-
-install: libpng.so.1.$(PNGVER)
-	-@mkdir $(prefix)/include
-	-@mkdir $(prefix)/lib
-	cp png.h $(prefix)/include
-	cp pngconf.h $(prefix)/include
-	chmod 644 $(prefix)/include/png.h
-	chmod 644 $(prefix)/include/pngconf.h
-	cp libpng.so.1.$(PNGVER) $(prefix)/lib
-	chmod 755 $(prefix)/lib/libpng.so.1.$(PNGVER)
-	-@/bin/rm $(prefix)/lib/libpng.so.1 $(prefix)/lib/libpng.so
-	(cd $(prefix)/lib; ln -sf libpng.so.1.$(PNGVER) libpng.so.1; \
-	 ln -sf libpng.so.1 libpng.so)
-
-clean:
-	rm -f *.o libpng.so.1.$(PNGVER) libpng.so.1 libpng.so pngtest pngout.png
-
-# DO NOT DELETE THIS LINE -- make depend depends on it.
-
-png.o: png.h pngconf.h
-pngerror.o: png.h pngconf.h
-pngrio.o: png.h pngconf.h
-pngwio.o: png.h pngconf.h
-pngmem.o: png.h pngconf.h
-pngrcb.o: png.h pngconf.h
-pngread.o: png.h pngconf.h
-pngrtran.o: png.h pngconf.h
-pngrutil.o: png.h pngconf.h
-pngtest.o: png.h pngconf.h
-pngtrans.o: png.h pngconf.h
-pngwrite.o: png.h pngconf.h
-pngwtran.o: png.h pngconf.h
-pngwutil.o: png.h pngconf.h
-pngpread.o: png.h pngconf.h

makefile.tc

@@ -1,72 +0,0 @@
-# Makefile for libpng
-# TurboC++ 3.0 (Note: All modules are compiled in C mode)
-
-# To use, do "make -fmakefile.tc"
-
-# ------------- Turbo C++ 3.0 -------------
-MODEL=-ml
-CFLAGS=-O2 -Z $(MODEL) -I..\zlib
-CC=tcc
-LD=tcc
-LIB=tlib
-LDFLAGS=$(MODEL)
-O=.obj
-
-# variables
-OBJS1 = png$(O) pngrcb$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O) pngmem$(O) pngpread$(O)
-OBJS2 = pngread$(O) pngerror$(O) pngwrite$(O) pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
-OBJSL1 = +png$(O) +pngrcb$(O) +pngrutil$(O) +pngtrans$(O) +pngwutil$(O) +pngmem$(O) +pngpread$(O)
-OBJSL2 = +pngread$(O) +pngerror$(O) +pngwrite$(O) +pngrtran$(O) +pngwtran$(O) +pngrio$(O) +pngwio$(O)
-
-all: libpng.lib
-
-png$(O): png.h pngconf.h
-		  $(CC) -c $(CFLAGS) $*.c
-
-pngrcb$(O): png.h pngconf.h
-		  $(CC) -c $(CFLAGS) $*.c
-
-pngread$(O): png.h pngconf.h
-		  $(CC) -c $(CFLAGS) $*.c
-
-pngpread$(O): png.h pngconf.h
-		  $(CC) -c $(CFLAGS) $*.c
-
-pngrtran$(O): png.h pngconf.h
-		  $(CC) -c $(CFLAGS) $*.c
-
-pngrutil$(O): png.h pngconf.h
-		  $(CC) -c $(CFLAGS) $*.c
-
-pngerror$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngmem$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngrio$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngwio$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngtest$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngtrans$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngwrite$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngwtran$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-pngwutil$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
-
-libpng.lib: $(OBJS1) $(OBJS2)
-        $(LIB) libpng +$(OBJSL1)
-        $(LIB) libpng +$(OBJSL2)
-
-# End of makefile for libpng

png.5

@@ -0,0 +1,58 @@
+.TH PNG 5 "September 19, 1999"
+.SH NAME
+png \- Portable Network Graphics (PNG) format
+.SH DESCRIPTION
+PNG (Portable Network Graphics) is an extensible file format for the
+lossless, portable, well-compressed storage of raster images. PNG provides
+a patent-free replacement for GIF and can also replace many
+common uses of TIFF. Indexed-color, grayscale, and truecolor images are
+supported, plus an optional alpha channel. Sample depths range from
+1 to 16 bits.
+.br
+
+PNG is designed to work well in online viewing applications, such as the
+World Wide Web, so it is fully streamable with a progressive display
+option. PNG is robust, providing both full file integrity checking and
+fast, simple detection of common transmission errors. Also, PNG can store
+gamma and chromaticity data for improved color matching on heterogeneous
+platforms.
+
+.SH "SEE ALSO"
+.IR libpng(3), zlib(3), deflate(5), and zlib(5)
+.LP
+PNG 1.1 specification, January 1999:
+.IP
+.br
+http://www.cdrom.com/pub/png
+.LP
+PNG 1.0 specification, October 1996:
+.IP
+.br
+RFC 2083
+.IP
+.br
+ftp://ds.internic.net/rfc/rfc2083.txt
+.br
+or (as a W3C Recommendation) at
+.br
+http://www.w3.org/TR/REC-png.html
+.SH AUTHORS
+This man page: Glenn Randers-Pehrson
+.LP
+Portable Network Graphics (PNG) Specification Version 1.2 (July 8, 1999):
+Glenn Randers-Pehrson and others (png-list@ccrc.wustl.edu).
+.LP
+Portable Network Graphics (PNG) Specification Version 1.0 (October 1, 1996):
+Thomas Boutell and others (png-list@ccrc.wustl.edu).
+.LP
+
+
+.SH COPYRIGHT NOTICE
+The PNG-1.2 specification is copyright (c) 1999 Glenn Randers-Pehrson.
+See the specification for conditions of use and distribution.
+.LP
+The PNG-1.0 specification is copyright (c) 1996 Massachussets Institute of
+Technology.  See the specification for conditions of use and distribution.
+.LP
+.\" end of man page
+

png.c

@@ -1,41 +1,47 @@
 
-/* png.c - location for general purpose png functions
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-   */
+/* png.c - location for general purpose libpng functions
+ *
+ * libpng version 1.0.4 - September 19, 1999
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ * 
+ */
 
 #define PNG_INTERNAL
 #define PNG_NO_EXTERN
 #include "png.h"
 
-/* version information for c files.  This better match the version
-   string defined in png.h */
-char png_libpng_ver[] = "0.89";
+/* Version information for C files.  This had better match the version
+ * string defined in png.h.
+ */
 
-/* place to hold the signiture string for a png file. */
+char png_libpng_ver[12] = "1.0.4";
+
+/* Place to hold the signature string for a PNG file. */
 png_byte FARDATA png_sig[8] = {137, 80, 78, 71, 13, 10, 26, 10};
 
-/* constant strings for known chunk types.  If you need to add a chunk,
-   add a string holding the name here.  If you want to make the code
-   portable to EBCDIC machines, use ASCII numbers, not characters. */
-png_byte FARDATA png_IHDR[4] = { 73,  72,  68,  82};
-png_byte FARDATA png_IDAT[4] = { 73,  68,  65,  84};
-png_byte FARDATA png_IEND[4] = { 73,  69,  78,  68};
-png_byte FARDATA png_PLTE[4] = { 80,  76,  84,  69};
-png_byte FARDATA png_gAMA[4] = {103,  65,  77,  65};
-png_byte FARDATA png_sBIT[4] = {115,  66,  73,  84};
-png_byte FARDATA png_cHRM[4] = { 99,  72,  82,  77};
-png_byte FARDATA png_tRNS[4] = {116,  82,  78,  83};
-png_byte FARDATA png_bKGD[4] = { 98,  75,  71,  68};
-png_byte FARDATA png_hIST[4] = {104,  73,  83,  84};
-png_byte FARDATA png_tEXt[4] = {116,  69,  88, 116};
-png_byte FARDATA png_zTXt[4] = {122,  84,  88, 116};
-png_byte FARDATA png_pHYs[4] = {112,  72,  89, 115};
-png_byte FARDATA png_oFFs[4] = {111,  70,  70, 115};
-png_byte FARDATA png_tIME[4] = {116,  73,  77,  69};
+/* Constant strings for known chunk types.  If you need to add a chunk,
+ * add a string holding the name here.  If you want to make the code
+ * portable to EBCDIC machines, use ASCII numbers, not characters.
+ */
+png_byte FARDATA png_IHDR[5] = { 73,  72,  68,  82, '\0'};
+png_byte FARDATA png_IDAT[5] = { 73,  68,  65,  84, '\0'};
+png_byte FARDATA png_IEND[5] = { 73,  69,  78,  68, '\0'};
+png_byte FARDATA png_PLTE[5] = { 80,  76,  84,  69, '\0'};
+png_byte FARDATA png_bKGD[5] = { 98,  75,  71,  68, '\0'};
+png_byte FARDATA png_cHRM[5] = { 99,  72,  82,  77, '\0'};
+png_byte FARDATA png_gAMA[5] = {103,  65,  77,  65, '\0'};
+png_byte FARDATA png_hIST[5] = {104,  73,  83,  84, '\0'};
+png_byte FARDATA png_oFFs[5] = {111,  70,  70, 115, '\0'};
+png_byte FARDATA png_pCAL[5] = {112,  67,  65,  76, '\0'};
+png_byte FARDATA png_pHYs[5] = {112,  72,  89, 115, '\0'};
+png_byte FARDATA png_sBIT[5] = {115,  66,  73,  84, '\0'};
+png_byte FARDATA png_sRGB[5] = {115,  82,  71,  66, '\0'};
+png_byte FARDATA png_tEXt[5] = {116,  69,  88, 116, '\0'};
+png_byte FARDATA png_tIME[5] = {116,  73,  77,  69, '\0'};
+png_byte FARDATA png_tRNS[5] = {116,  82,  78,  83, '\0'};
+png_byte FARDATA png_zTXt[5] = {122,  84,  88, 116, '\0'};
 
 /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 
@@ -51,47 +57,81 @@ int FARDATA png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
 /* offset to next interlace block in the y direction */
 int FARDATA png_pass_yinc[] = {8, 8, 8, 4, 4, 2, 2};
 
-/* width of interlace block */
-/* this is not currently used - if you need it, uncomment it here and
-   in png.h
+/* Width of interlace block.  This is not currently used - if you need
+ * it, uncomment it here and in png.h
 int FARDATA png_pass_width[] = {8, 4, 4, 2, 2, 1, 1};
 */
 
-/* height of interlace block */
-/* this is not currently used - if you need it, uncomment it here and
-   in png.h
+/* Height of interlace block.  This is not currently used - if you need
+ * it, uncomment it here and in png.h
 int FARDATA png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
 */
 
-/* mask to determine which pixels are valid in a pass */
+/* Mask to determine which pixels are valid in a pass */
 int FARDATA png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
 
-/* mask to determine which pixels to overwrite while displaying */
+/* Mask to determine which pixels to overwrite while displaying */
 int FARDATA png_pass_dsp_mask[] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
 
 
+/* Tells libpng that we have already handled the first "num_bytes" bytes
+ * of the PNG file signature.  If the PNG data is embedded into another
+ * stream we can set num_bytes = 8 so that libpng will not attempt to read
+ * or write any of the magic bytes before it starts on the IHDR.
+ */
+void
+png_set_sig_bytes(png_structp png_ptr, int num_bytes)
+{
+   png_debug(1, "in png_set_sig_bytes\n");
+   if (num_bytes > 8)
+      png_error(png_ptr, "Too many bytes for PNG signature.");
+
+   png_ptr->sig_bytes = num_bytes < 0 ? 0 : num_bytes;
+}
+
+/* Checks whether the supplied bytes match the PNG signature.  We allow
+ * checking less than the full 8-byte signature so that those apps that
+ * already read the first few bytes of a file to determine the file type
+ * can simply check the remaining bytes for extra assurance.  Returns
+ * an integer less than, equal to, or greater than zero if sig is found,
+ * respectively, to be less than, to match, or be greater than the correct
+ * PNG signature (this is the same behaviour as strcmp, memcmp, etc).
+ */
+int
+png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
+{
+   if (num_to_check > 8)
+      num_to_check = 8;
+   else if (num_to_check < 1)
+      return (0);
+
+   if (start > 7)
+      return (0);
+
+   if (start + num_to_check > 8)
+      num_to_check = 8 - start;
+
+   return ((int)(png_memcmp(&sig[start], &png_sig[start], num_to_check)));
+}
+
+/* (Obsolete) function to check signature bytes.  It does not allow one
+ * to check a partial signature.  This function might be removed in the
+ * future - use png_sig_cmp().  Returns true (nonzero) if the file is a PNG.
+ */
 int
 png_check_sig(png_bytep sig, int num)
 {
-   if (num > 8)
-      num = 8;
-   if (num < 1)
-      return 0;
-
-   return (!png_memcmp(sig, png_sig, num));
+  return ((int)!png_sig_cmp(sig, (png_size_t)0, (png_size_t)num));
 }
 
 /* Function to allocate memory for zlib. */
 voidpf
 png_zalloc(voidpf png_ptr, uInt items, uInt size)
 {
-   png_voidp ptr;
-   png_uint_32 num_bytes;
+   png_uint_32 num_bytes = (png_uint_32)items * size;
+   png_voidp ptr = (png_voidp)png_malloc((png_structp)png_ptr, num_bytes);
 
-   ptr = png_large_malloc((png_structp)png_ptr,
-      (png_uint_32)items * (png_uint_32)size);
-   num_bytes = (png_uint_32)items * (png_uint_32)size;
-   if (num_bytes > (png_uint_32)0x7fff)
+   if (num_bytes > (png_uint_32)0x8000L)
    {
       png_memset(ptr, 0, (png_size_t)0x8000L);
       png_memset((png_bytep)ptr + (png_size_t)0x8000L, 0,
@@ -101,128 +141,219 @@ png_zalloc(voidpf png_ptr, uInt items, uInt size)
    {
       png_memset(ptr, 0, (png_size_t)num_bytes);
    }
-   return (voidpf)(ptr);
+   return ((voidpf)ptr);
 }
 
 /* function to free memory for zlib */
 void
 png_zfree(voidpf png_ptr, voidpf ptr)
 {
-   png_large_free((png_structp)png_ptr, (png_voidp)ptr);
+   png_free((png_structp)png_ptr, (png_voidp)ptr);
 }
 
-/* reset the crc variable to 32 bits of 1's.  Care must be taken
-   in case crc is > 32 bits to leave the top bits 0 */
+/* Reset the CRC variable to 32 bits of 1's.  Care must be taken
+ * in case CRC is > 32 bits to leave the top bits 0.
+ */
 void
 png_reset_crc(png_structp png_ptr)
 {
-   /* set crc to all 1's */
-   png_ptr->crc = 0xffffffffL;
+   png_ptr->crc = crc32(0, Z_NULL, 0);
 }
 
-/* Note: the crc code below was copied from the sample code in the
-   PNG spec, with appropriate modifications made to ensure the
-   variables are large enough */
-
-/* table of crc's of all 8-bit messages.  If you wish to png_malloc this
-   table, turn this into a pointer, and png_malloc it in make_crc_table().
-   You may then want to hook it into png_struct and free it with the
-   destroy functions. */
-static png_uint_32 crc_table[256];
-
-/* Flag: has the table been computed? Initially false. */
-static int crc_table_computed = 0;
-
-/* make the table for a fast crc */
-static void
-make_crc_table(void)
-{
-  png_uint_32 c;
-  int n, k;
-
-  for (n = 0; n < 256; n++)
-  {
-   c = (png_uint_32)n;
-   for (k = 0; k < 8; k++)
-     c = c & 1 ? 0xedb88320L ^ (c >> 1) : c >> 1;
-   crc_table[n] = c;
-  }
-  crc_table_computed = 1;
-}
-
-/* update a running crc with the bytes buf[0..len-1]--the crc should be
-   initialized to all 1's, and the transmitted value is the 1's complement
-   of the final running crc. */
-static png_uint_32
-update_crc(png_uint_32 crc, png_bytep buf, png_uint_32 len)
-{
-  png_uint_32 c;
-  png_bytep p;
-  png_uint_32 n;
-
-  c = crc;
-  p = buf;
-  n = len;
-
-  if (!crc_table_computed)
-  {
-   make_crc_table();
-  }
-
-  if (n > 0) do
-  {
-   c = crc_table[(png_byte)((c ^ (*p++)) & 0xff)] ^ (c >> 8);
-  } while (--n);
-
-  return c;
-}
-
-/* calculate the crc over a section of data.  Note that while we
-   are passing in a 32 bit value for length, on 16 bit machines, you
-   would need to use huge pointers to access all that data.  If you
-   need this, put huge here and above. */
+/* Calculate the CRC over a section of data.  We can only pass as
+ * much data to this routine as the largest single buffer size.  We
+ * also check that this data will actually be used before going to the
+ * trouble of calculating it.
+ */
 void
-png_calculate_crc(png_structp png_ptr, png_bytep ptr,
-   png_uint_32 length)
+png_calculate_crc(png_structp png_ptr, png_bytep ptr, png_size_t length)
 {
-   png_ptr->crc = update_crc(png_ptr->crc, ptr, length);
+   int need_crc = 1;
+
+   if (png_ptr->chunk_name[0] & 0x20)                     /* ancillary */
+   {
+      if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
+          (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
+         need_crc = 0;
+   }
+   else                                                    /* critical */
+   {
+      if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
+         need_crc = 0;
+   }
+
+   if (need_crc)
+      png_ptr->crc = crc32(png_ptr->crc, ptr, (uInt)length);
 }
 
+/* Allocate the memory for an info_struct for the application.  We don't
+ * really need the png_ptr, but it could potentially be useful in the
+ * future.  This should be used in favour of malloc(sizeof(png_info))
+ * and png_info_init() so that applications that want to use a shared
+ * libpng don't have to be recompiled if png_info changes size.
+ */
 png_infop
 png_create_info_struct(png_structp png_ptr)
 {
    png_infop info_ptr;
 
+   png_debug(1, "in png_create_info_struct\n");
+   if(png_ptr == NULL) return (NULL);
+#ifdef PNG_USER_MEM_SUPPORTED
+   if ((info_ptr = (png_infop)png_create_struct_2(PNG_STRUCT_INFO,
+      png_ptr->malloc_fn)) != NULL)
+#else
    if ((info_ptr = (png_infop)png_create_struct(PNG_STRUCT_INFO)) != NULL)
+#endif
    {
-      png_memset(info_ptr, 0, sizeof(png_info));
-      png_ptr->do_free |= PNG_FREE_INFO;
+      png_info_init(info_ptr);
    }
 
-   return info_ptr;
+   return (info_ptr);
 }
 
+/* This function frees the memory associated with a single info struct.
+ * Normally, one would use either png_destroy_read_struct() or
+ * png_destroy_write_struct() to free an info struct, but this may be
+ * useful for some applications.
+ */
 void
-png_info_init(png_infop info)
+png_destroy_info_struct(png_structp png_ptr, png_infopp info_ptr_ptr)
 {
+   png_infop info_ptr = NULL;
+
+   png_debug(1, "in png_destroy_info_struct\n");
+   if (info_ptr_ptr != NULL)
+      info_ptr = *info_ptr_ptr;
+
+   if (info_ptr != NULL)
+   {
+      png_info_destroy(png_ptr, info_ptr);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+      png_destroy_struct_2((png_voidp)info_ptr, png_ptr->free_fn);
+#else
+      png_destroy_struct((png_voidp)info_ptr);
+#endif
+      *info_ptr_ptr = (png_infop)NULL;
+   }
+}
+
+/* Initialize the info structure.  This is now an internal function (0.89)
+ * and applications using it are urged to use png_create_info_struct()
+ * instead.
+ */
+void
+png_info_init(png_infop info_ptr)
+{
+   png_debug(1, "in png_info_init\n");
    /* set everything to 0 */
-   png_memset(info, 0, sizeof (png_info));
+   png_memset(info_ptr, 0, sizeof (png_info));
+}
+
+/* This is an internal routine to free any memory that the info struct is
+ * pointing to before re-using it or freeing the struct itself.  Recall
+ * that png_free() checks for NULL pointers for us.
+ */
+void
+png_info_destroy(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
+   png_debug(1, "in png_info_destroy\n");
+   if (info_ptr->text != NULL)
+   {
+      int i;
+      for (i = 0; i < info_ptr->num_text; i++)
+      {
+         png_free(png_ptr, info_ptr->text[i].key);
+      }
+      png_free(png_ptr, info_ptr->text);
+   }
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+   png_free(png_ptr, info_ptr->pcal_purpose);
+   png_free(png_ptr, info_ptr->pcal_units);
+   if (info_ptr->pcal_params != NULL)
+   {
+      int i;
+      for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
+      {
+         png_free(png_ptr, info_ptr->pcal_params[i]);
+      }
+      png_free(png_ptr, info_ptr->pcal_params);
+   }
+#endif
+
+   png_info_init(info_ptr);
 }
 
 /* This function returns a pointer to the io_ptr associated with the user
-   functions.  The application should free any memory associated with this
-   pointer before png_write_destroy and png_read_destroy are called. */
+ * functions.  The application should free any memory associated with this
+ * pointer before png_write_destroy() or png_read_destroy() are called.
+ */
 png_voidp
 png_get_io_ptr(png_structp png_ptr)
 {
-   return png_ptr->io_ptr;
+   return (png_ptr->io_ptr);
 }
- 
-/* Initialize the default input/output functions for the png file.  If you
-   change the read, or write routines, you can call either png_set_read_fn()
-   or png_set_write_fn() instead of png_init_io(). */
+
+#if !defined(PNG_NO_STDIO)
+/* Initialize the default input/output functions for the PNG file.  If you
+ * use your own read or write routines, you can call either png_set_read_fn()
+ * or png_set_write_fn() instead of png_init_io().
+ */
 void
 png_init_io(png_structp png_ptr, FILE *fp)
 {
+   png_debug(1, "in png_init_io\n");
    png_ptr->io_ptr = (png_voidp)fp;
 }
+#endif
+
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+/* Convert the supplied time into an RFC 1123 string suitable for use in
+ * a "Creation Time" or other text-based time string.
+ */
+png_charp
+png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
+{
+   static PNG_CONST char short_months[12][4] =
+        {"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+         "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"};
+
+   if (png_ptr->time_buffer == NULL)
+   {
+      png_ptr->time_buffer = (png_charp)png_malloc(png_ptr, (png_uint_32)(29*
+         sizeof(char)));
+   }
+
+#ifdef USE_FAR_KEYWORD
+   {
+      char near_time_buf[29];
+      sprintf(near_time_buf, "%d %s %d %02d:%02d:%02d +0000",
+               ptime->day % 32, short_months[(ptime->month - 1) % 12],
+               ptime->year, ptime->hour % 24, ptime->minute % 60,
+               ptime->second % 61);
+      png_memcpy(png_ptr->time_buffer, near_time_buf,
+      29*sizeof(char));
+   }
+#else
+   sprintf(png_ptr->time_buffer, "%d %s %d %02d:%02d:%02d +0000",
+               ptime->day % 32, short_months[(ptime->month - 1) % 12],
+               ptime->year, ptime->hour % 24, ptime->minute % 60,
+               ptime->second % 61);
+#endif
+   return ((png_charp)png_ptr->time_buffer);
+}
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+
+png_charp
+png_get_copyright(png_structp png_ptr)
+{
+   if(png_ptr == NULL)
+     /* silence compiler warning about unused png_ptr */ ;
+   return("\n libpng version 1.0.4 - September 19, 1999\n\
+   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.\n\
+   Copyright (c) 1996, 1997 Andreas Dilger\n\
+   Copyright (c) 1998, 1999 Glenn Randers-Pehrson\n");
+}

pngasmrd.h

@@ -0,0 +1,32 @@
+/* pngasmrd.h - assembler version of utilities to read a PNG file
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1999 Glenn Randers-Pehrson
+ *
+ */
+
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+
+/* Set this in the makefile for VC++ on Pentium, not in pngconf.h */
+#ifdef PNG_USE_PNGVCRD
+/* Platform must be Pentium.  Makefile must assemble and load pngvcrd.c .
+ * MMX will be detected at run time and used if present.
+ */
+#define PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#define PNG_HAVE_ASSEMBLER_READ_INTERLACE
+#define PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#endif
+
+/* Set this in the makefile for gcc on Pentium, not in pngconf.h */
+#ifdef PNG_USE_PNGGCCRD
+/* Platform must be Pentium.  Makefile must assemble and load pnggccrd.c
+ * (not available in libpng 1.0.4).
+ * MMX will be detected at run time and used if present.
+ */
+#define PNG_HAVE_ASSEMBLER_COMBINE_ROW
+#define PNG_HAVE_ASSEMBLER_READ_INTERLACE
+#define PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+#endif
+
+#endif

pngchang.txt

@@ -1,103 +0,0 @@
-pngchange.txt - changes for libpng
-
-version 0.2
-   added reader into png.h
-   fixed small problems in stub file
-version 0.3
-   added pull reader
-   split up pngwrite.c to several files
-   added pnglib.txt
-   added example.c
-   cleaned up writer, adding a few new tranformations
-   fixed some bugs in writer
-   interfaced with zlib 0.5
-   added K&R support
-   added check for 64 KB blocks for 16 bit machines
-version 0.4
-   cleaned up code and commented code
-   simplified time handling into png_time
-   created png_color_16 and png_color_8 to handle color needs
-   cleaned up color type defines
-   fixed various bugs
-   made various names more consistant
-   interfaced with zlib 0.71
-   cleaned up zTXt reader and writer (using zlib's Reset functions)
-   split transformations into pngrtran.c and pngwtran.c
-version 0.5
-   interfaced with zlib 0.8
-   fixed many reading and writing bugs
-   saved using 3 spaces instead of tabs
-version 0.6
-   added png_large_malloc() and png_large_free()
-   added png_size_t
-   cleaned up some compiler warnings
-   added png_start_read_image()
-version 0.7
-   cleaned up lots of bugs
-   finished dithering and other stuff
-   added test program
-   changed name from pnglib to libpng
-version 0.71
-   changed pngtest.png for zlib 0.93
-   fixed error in libpng.txt and example.c
-version 0.8
-   cleaned up some bugs
-   added png_set_filler()
-   split up pngstub.c into pngmem.c, pngio.c, and pngerror.c
-   added #define's to remove unwanted code
-   moved png_info_init() to png.c
-   added old_size into png_realloc()
-   added functions to manually set filtering and compression info
-   changed compression parameters based on image type
-   optimized filter selection code
-   added version info
-   changed external functions passing floats to doubles (k&r problems?)
-   put all the configurable stuff in pngconf.h
-   enabled png_set_shift to work with paletted images on read
-   added png_read_update_info() - updates info structure with
-      transformations
-version 0.81
-   incorporated Tim Wegner's medium model code (thanks, Tim)
-version 0.85
-   added more medium model code (almost everythings a far)
-   added i/o, error, and memory callback functions
-   fixed some bugs (16 bit, 4 bit interlaced, etc.)
-   added first run progressive reader (barely tested)
-version 0.86
-   fixed bugs
-   improved documentation
-version 0.87
-   fixed medium model bugs
-   fixed other bugs introduced in 0.85 and 0.86
-   added some minor documentation
-version 0.88
-   fixed progressive bugs
-   replaced tabs with spaces
-   cleaned up documentation
-   added callbacks for read/write and warning/error functions
-version 0.89 
-   added new initialization API to make libpng work better with shared libs
-      we now have png_create_read_struct(), png_create_write_struct(),
-      png_create_info_struct(), png_destroy_read_struct(), and
-      png_destroy_write_struct() instead of the separate calls to
-      malloc and png_read_init(), png_info_init(), and png_write_init()
-   changed warning/error callback functions to fix bug - this means you
-      should use the new initialization API if you were using the old
-      png_set_message_fn() calls, and that the old API no longer exists
-      so that people are aware that they need to change their code
-   changed filter selection API to allow selection of multiple filters
-      since it didn't work in previous versions of libpng anyways
-   optimized filter selection code    
-   fixed png_set_background() to allow using an arbitrary RGB color for
-      paletted images
-   fixed gamma and background correction for paletted images, so
-      png_correct_palette is not needed unless you are correcting an
-      external palette (you will need to #define PNG_CORRECT_PALETTE_SUPPORTED
-      in pngconf.h)
-   fixed bug with Borland 64K memory allocation (Alexander Lehmann)
-   fixed bug in interlace handling (Smaraderagd, I think)
-   added more error checking for writing and image to reduce invalid files
-   separated read and write functions so that they won't both be linked
-      into a binary when only reading or writing functionality is used
-   new pngtest image also has interlacing and zTXt
-   updated dcumentation to reflect new API

pngconf.h

@@ -1,69 +1,88 @@
 
-/* pngconf.c - machine configurable file for libpng
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-   */
+/* pngconf.h - machine configurable file for libpng
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ */
 
 /* Any machine specific code is near the front of this file, so if you
-   are configuring libpng for a machine, you may want to read the section
-   starting here down to where it starts to typedef png_color, png_text,
-   and png_info */
+ * are configuring libpng for a machine, you may want to read the section
+ * starting here down to where it starts to typedef png_color, png_text,
+ * and png_info.
+ */
 
 #ifndef PNGCONF_H
 #define PNGCONF_H
 
-/* this is the size of the compression buffer, and thus the size of
-   an IDAT chunk.  Make this whatever size you feel is best for your
-   machine.  One of these will be allocated per png_struct.  When this
-   is full, it writes the data to the disk, and does some other
-   calculations.  Making this an extreamly small size will slow
-   the library down, but you may want to experiment to determine
-   where it becomes significant, if you are concerned with memory
-   usage.  Note that zlib allocates at least 32Kb also.  For readers,
-   this describes the size of the buffer available to read the data in.
-   Unless this gets smaller then the size of a row (compressed),
-   it should not make much difference how big this is.  */
 
+/* This is the size of the compression buffer, and thus the size of
+ * an IDAT chunk.  Make this whatever size you feel is best for your
+ * machine.  One of these will be allocated per png_struct.  When this
+ * is full, it writes the data to the disk, and does some other
+ * calculations.  Making this an extremely small size will slow
+ * the library down, but you may want to experiment to determine
+ * where it becomes significant, if you are concerned with memory
+ * usage.  Note that zlib allocates at least 32Kb also.  For readers,
+ * this describes the size of the buffer available to read the data in.
+ * Unless this gets smaller than the size of a row (compressed),
+ * it should not make much difference how big this is.
+ */
+
+#ifndef PNG_ZBUF_SIZE
 #define PNG_ZBUF_SIZE 8192
-
-/* While libpng currently uses zlib for it's compression, it has been designed
-   to stand on it's own.  Towards this end, there are two defines that are
-   used to help portability between machines.  To make it simpler to
-   setup libpng on a machine, this currently uses zlib's definitions, so
-   any changes should be made in zlib.  Libpng will check zlib's settings
-   and adjust it's own accordingly. */
-
-/* if you are running on a machine where you cannot allocate more then
-   64K of memory, uncomment this.  While libpng will not normally need
-   that much memory in a chunk (unless you load up a very large file),
-   zlib needs to know how big of a chunk it can use, and libpng thus
-   makes sure to check any memory allocation to verify it will fit
-   into memory.
-#define PNG_MAX_ALLOC_64K
-*/
-#ifdef MAXSEG_64K
-#define PNG_MAX_ALLOC_64K
 #endif
 
-/* this protects us against compilers which run on a windowing system
-   and thus don't have or would rather us not use the stdio types:
-   stdin, stdout, and stderr.  The only one currently used is stderr
-   in png_error() and png_warning().  #defining PNG_NO_STDIO will
-   prevent these from being compiled and used. */
+/* If you are running on a machine where you cannot allocate more
+ * than 64K of memory at once, uncomment this.  While libpng will not
+ * normally need that much memory in a chunk (unless you load up a very
+ * large file), zlib needs to know how big of a chunk it can use, and
+ * libpng thus makes sure to check any memory allocation to verify it
+ * will fit into memory.
+#define PNG_MAX_MALLOC_64K
+ */
+#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
+#define PNG_MAX_MALLOC_64K
+#endif
 
-/* #define PNG_NO_STDIO */
+/* This protects us against compilers that run on a windowing system
+ * and thus don't have or would rather us not use the stdio types:
+ * stdin, stdout, and stderr.  The only one currently used is stderr
+ * in png_error() and png_warning().  #defining PNG_NO_CONSOLE_IO will
+ * prevent these from being compiled and used. #defining PNG_NO_STDIO
+ * will also prevent these, plus will prevent the entire set of stdio
+ * macros and functions (FILE *, printf, etc.) from being compiled and used,
+ * unless (PNG_DEBUG > 0) has been #defined.
+ *
+ * #define PNG_NO_CONSOLE_IO
+ * #define PNG_NO_STDIO
+ */
 
-/* this macro protects us against machines that don't have function
-   prototypes.  If your compiler does not handle function prototypes,
-   define this macro.  I've always been able to use _NO_PROTO as the
-   indicator, but you may need to drag the empty declaration out in
-   front of here, or change the ifdef to suit your own needs. */
+#  ifdef PNG_NO_STDIO
+#    ifndef PNG_NO_CONSOLE_IO
+#      define PNG_NO_CONSOLE_IO
+#    endif
+#    ifdef PNG_DEBUG
+#      if (PNG_DEBUG > 0)
+#        include <stdio.h>
+#      endif
+#    endif
+#  else
+#    include <stdio.h>
+#  endif
+
+/* This macro protects us against machines that don't have function
+ * prototypes (ie K&R style headers).  If your compiler does not handle
+ * function prototypes, define this macro and use the included ansi2knr.
+ * I've always been able to use _NO_PROTO as the indicator, but you may
+ * need to drag the empty declaration out in front of here, or change the
+ * ifdef to suit your own needs.
+ */
 #ifndef PNGARG
 
-#ifdef OF
+#ifdef OF /* zlib prototype munger */
 #define PNGARG(arglist) OF(arglist)
 #else
 
@@ -77,39 +96,90 @@
 
 #endif /* PNGARG */
 
+/* Try to determine if we are compiling on a Mac.  Note that testing for
+ * just __MWERKS__ is not good enough, because the Codewarrior is now used
+ * on non-Mac platforms.
+ */
+#ifndef MACOS
+#if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
+    defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
+#define MACOS
+#endif
+#endif
+
 /* enough people need this for various reasons to include it here */
 #if !defined(MACOS) && !defined(RISCOS)
 #include <sys/types.h>
 #endif
-/* need the time information for reading tIME chunks */
-#include <time.h>
 
-/* for FILE.  If you are not using standard io, you don't need this */
-#include <stdio.h>
+/* This is an attempt to force a single setjmp behaviour on Linux.  If
+ * the X config stuff didn't define _BSD_SOURCE we wouldn't need this.
+ */
+#ifdef __linux__
+#ifdef _BSD_SOURCE
+#define _PNG_SAVE_BSD_SOURCE
+#undef _BSD_SOURCE
+#endif
+#ifdef _SETJMP_H
+__png.h__ already includes setjmp.h
+__dont__ include it again
+#endif
+#endif /* __linux__ */
 
 /* include setjmp.h for error handling */
 #include <setjmp.h>
 
+#ifdef __linux__
+#ifdef _PNG_SAVE_BSD_SOURCE
+#define _BSD_SOURCE
+#undef _PNG_SAVE_BSD_SOURCE
+#endif
+#endif /* __linux__ */
+
 #ifdef BSD
 #include <strings.h>
 #else
 #include <string.h>
 #endif
 
-/* other defines for things like memory and the like can go here.  These
-   are the only files included in libpng, so if you need to change them,
-   change them here.  They are only included if PNG_INTERNAL is defined. */
+/* Other defines for things like memory and the like can go here.  */
 #ifdef PNG_INTERNAL
 #include <stdlib.h>
-#include <ctype.h>
+
+/* The functions exported by PNG_EXTERN are PNG_INTERNAL functions, which
+ * aren't usually used outside the library (as far as I know), so it is
+ * debatable if they should be exported at all.  In the future, when it is
+ * possible to have run-time registry of chunk-handling functions, some of
+ * these will be made available again.
+#define PNG_EXTERN extern
+ */
+#define PNG_EXTERN
+
+/* Other defines specific to compilers can go here.  Try to keep
+ * them inside an appropriate ifdef/endif pair for portability.
+ */
+
+#if defined(MACOS)
+/* We need to check that <math.h> hasn't already been included earlier
+ * as it seems it doesn't agree with <fp.h>, yet we should really use
+ * <fp.h> if possible.
+ */
+#if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
+#include <fp.h>
+#endif
+#else
 #include <math.h>
+#endif
 
-/* other defines specific to compilers can go here.  Try to keep
-   them inside an appropriate ifdef/endif pair for portability */
+/* Codewarrior on NT has linking problems without this. */
+#if (defined(__MWERKS__) && defined(WIN32)) || defined(__STDC__)
+#define PNG_ALWAYS_EXTERN
+#endif
 
-/* for some reason, Borland C++ defines memcmp, etc. in mem.h, not
-   stdlib.h like it should (I think).  Or perhaps this is a C++
-   feature */
+/* For some reason, Borland C++ defines memcmp, etc. in mem.h, not
+ * stdlib.h like it should (I think).  Or perhaps this is a C++
+ * "feature"?
+ */
 #ifdef __TURBOC__
 #include <mem.h>
 #include "alloc.h"
@@ -119,112 +189,371 @@
 #include <malloc.h>
 #endif
 
-/* this controls how fine the dithering gets.  As this allocates
-   a largish chunk of memory (32K), those who are not as concerned
-   with dithering quality can decrease some or all of these */
+/* This controls how fine the dithering gets.  As this allocates
+ * a largish chunk of memory (32K), those who are not as concerned
+ * with dithering quality can decrease some or all of these.
+ */
+#ifndef PNG_DITHER_RED_BITS
 #define PNG_DITHER_RED_BITS 5
+#endif
+#ifndef PNG_DITHER_GREEN_BITS
 #define PNG_DITHER_GREEN_BITS 5
+#endif
+#ifndef PNG_DITHER_BLUE_BITS
 #define PNG_DITHER_BLUE_BITS 5
+#endif
 
-/* this controls how fine the gamma correction becomes when you
-   are only interested in 8 bits anyway.  Increasing this value
-   results in more memory being used, and more pow() functions
-   being called to fill in the gamma tables.  Don't get this
-   value less then 8, and even that may not work (I haven't tested
-   it). */
+/* This controls how fine the gamma correction becomes when you
+ * are only interested in 8 bits anyway.  Increasing this value
+ * results in more memory being used, and more pow() functions
+ * being called to fill in the gamma tables.  Don't set this value
+ * less then 8, and even that may not work (I haven't tested it).
+ */
 
+#ifndef PNG_MAX_GAMMA_8
 #define PNG_MAX_GAMMA_8 11
+#endif
+
+/* This controls how much a difference in gamma we can tolerate before
+ * we actually start doing gamma conversion.
+ */
+#ifndef PNG_GAMMA_THRESHOLD
+#define PNG_GAMMA_THRESHOLD 0.05
+#endif
 
 #endif /* PNG_INTERNAL */
 
-/* the following uses const char * instead of char * for error
-   and warning message functions, so some compilers won't complain.
-   If you want to use const, define PNG_USE_CONST here.  It is not
-   normally defined to make configuration easier, as it is not a
-   critical part of the code.
-   */
+/* The following uses const char * instead of char * for error
+ * and warning message functions, so some compilers won't complain.
+ * If you do not want to use const, define PNG_NO_CONST here.
+ */
 
-#ifdef PNG_USE_CONST
+#ifndef PNG_NO_CONST
 #  define PNG_CONST const
 #else
 #  define PNG_CONST
 #endif
 
-/* The following defines give you the ability to remove code
-   from the library that you will not be using.  I wish I
-   could figure out how to automate this, but I can't do
-   that without making it seriously hard on the users.  So
-   if you are not using an ability, change the #define to
-   and #undef, and that part of the library will not be
-   compiled.  If your linker can't find a function, you
-   may want to make sure the ability is defined here.
-   Some of these depend upon some others being defined.
-   I haven't figured out all the interactions here, so
-   you may have to experiment awhile to get everything
-   to compile.
-   */
+/* The following defines give you the ability to remove code from the
+ * library that you will not be using.  I wish I could figure out how to
+ * automate this, but I can't do that without making it seriously hard
+ * on the users.  So if you are not using an ability, change the #define
+ * to and #undef, and that part of the library will not be compiled.  If
+ * your linker can't find a function, you may want to make sure the
+ * ability is defined here.  Some of these depend upon some others being
+ * defined.  I haven't figured out all the interactions here, so you may
+ * have to experiment awhile to get everything to compile.  If you are
+ * creating or using a shared library, you probably shouldn't touch this,
+ * as it will affect the size of the structures, and this will cause bad
+ * things to happen if the library and/or application ever change.
+ */
 
 /* Any transformations you will not be using can be undef'ed here */
-#define PNG_PROGRESSIVE_READ_SUPPORTED
-#define PNG_READ_INTERLACING_SUPPORTED
+
+/* GR-P, 0.96a: Set "*TRANSFORMS_SUPPORTED as default but allow user
+   to turn it off with "*TRANSFORMS_NOT_SUPPORTED" or *PNG_NO_*_TRANSFORMS
+   on the compile line, then pick and choose which ones to define without
+   having to edit this file. It is safe to use the *TRANSFORMS_NOT_SUPPORTED
+   if you only want to have a png-compliant reader/writer but don't need
+   any of the extra transformations.  This saves about 80 kbytes in a
+   typical installation of the library. (PNG_NO_* form added in version
+   1.0.1c, for consistency)
+ */
+
+
+#if !defined(PNG_READ_TRANSFORMS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_READ_TRANSFORMS)
+#define PNG_READ_TRANSFORMS_SUPPORTED
+#endif
+#if !defined(PNG_WRITE_TRANSFORMS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_WRITE_TRANSFORMS)
+#define PNG_WRITE_TRANSFORMS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+#ifndef PNG_NO_READ_EXPAND
 #define PNG_READ_EXPAND_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_SHIFT
 #define PNG_READ_SHIFT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_PACK
 #define PNG_READ_PACK_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_BGR
 #define PNG_READ_BGR_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_SWAP
 #define PNG_READ_SWAP_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_PACKSWAP
+#define PNG_READ_PACKSWAP_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_INVERT
 #define PNG_READ_INVERT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_DITHER
 #define PNG_READ_DITHER_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_BACKGROUND
 #define PNG_READ_BACKGROUND_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_16_TO_8
 #define PNG_READ_16_TO_8_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_FILLER
 #define PNG_READ_FILLER_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_GAMMA
 #define PNG_READ_GAMMA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_GRAY_TO_RGB
 #define PNG_READ_GRAY_TO_RGB_SUPPORTED
-#undef  PNG_CORRECT_PALETTE_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_SWAP_ALPHA
+#define PNG_READ_SWAP_ALPHA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_INVERT_ALPHA
+#define PNG_READ_INVERT_ALPHA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_STRIP_ALPHA
+#define PNG_READ_STRIP_ALPHA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_USER_TRANSFORM
+#define PNG_READ_USER_TRANSFORM_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_RGB_TO_GRAY
+#define PNG_READ_RGB_TO_GRAY_SUPPORTED
+#endif
+#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
 
-#define PNG_WRITE_INTERLACING_SUPPORTED
+#if !defined(PNG_NO_PROGRESSIVE_READ) && \
+ !defined(PNG_PROGRESSIVE_READ_NOT_SUPPORTED) /* if you don't do progressive   */
+#define PNG_PROGRESSIVE_READ_SUPPORTED       /* reading.  This is not talking */
+#endif                               /* about interlacing capability!  You'll */
+              /* still have interlacing unless you change the following line: */
+#define PNG_READ_INTERLACING_SUPPORTED /* required for PNG-compliant decoders */
+
+#ifndef PNG_NO_READ_COMPOSITED_NODIV
+#define PNG_READ_COMPOSITE_NODIV_SUPPORTED    /* well tested on Intel and SGI */
+#endif
+
+#ifndef PNG_NO_READ_EMPTY_PLTE
+#define PNG_READ_EMPTY_PLTE_SUPPORTED  /* useful for MNG applications */
+#endif
+
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+#ifndef PNG_NO_WRITE_SHIFT
 #define PNG_WRITE_SHIFT_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_PACK
 #define PNG_WRITE_PACK_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_BGR
 #define PNG_WRITE_BGR_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_SWAP
 #define PNG_WRITE_SWAP_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_PACKSWAP
+#define PNG_WRITE_PACKSWAP_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_INVERT
 #define PNG_WRITE_INVERT_SUPPORTED
-#define PNG_WRITE_FILLER_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_FILLER
+#define PNG_WRITE_FILLER_SUPPORTED  /* This is the same as WRITE_STRIP_ALPHA */
+#endif
+#ifndef PNG_NO_WRITE_SWAP_ALPHA
+#define PNG_WRITE_SWAP_ALPHA_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_INVERT_ALPHA
+#define PNG_WRITE_INVERT_ALPHA_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_USER_TRANSFORM
+#define PNG_WRITE_USER_TRANSFORM_SUPPORTED
+#endif
+#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */
+
+#define PNG_WRITE_INTERLACING_SUPPORTED  /* not required for PNG-compliant
+                                            encoders, but can cause trouble
+                                            if left undefined */
+
+#ifndef PNG_NO_WRITE_WEIGHTED_FILTER
+#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
+#endif
+
+#ifndef PNG_NO_WRITE_FLUSH
 #define PNG_WRITE_FLUSH_SUPPORTED
+#endif
 
-/* any chunks you are not interested in, you can undef here.  The
-   ones that allocate memory may be expecially important (hIST,
-   tEXt, zTXt, tRNS) Others will just save time and make png_info
-   smaller.  OPT_PLTE only disables the optional palette in RGB
-   and RGB Alpha images. */
+#ifndef PNG_NO_WRITE_EMPTY_PLTE
+#define PNG_WRITE_EMPTY_PLTE_SUPPORTED  /* useful for MNG applications */
+#endif
 
-#define PNG_READ_gAMA_SUPPORTED
-#define PNG_READ_sBIT_SUPPORTED
-#define PNG_READ_cHRM_SUPPORTED
-#define PNG_READ_tRNS_SUPPORTED
+#ifndef PNG_NO_STDIO
+#define PNG_TIME_RFC1123_SUPPORTED
+#endif
+
+/* This adds extra functions in pngget.c for accessing data from the
+ * info pointer (added in version 0.99)
+ * png_get_image_width()
+ * png_get_image_height()
+ * png_get_bit_depth()
+ * png_get_color_type()
+ * png_get_compression_type()
+ * png_get_filter_type()
+ * png_get_interlace_type()
+ * png_get_pixel_aspect_ratio()
+ * png_get_pixels_per_meter()
+ * png_get_x_offset_pixels()
+ * png_get_y_offset_pixels()
+ * png_get_x_offset_microns()
+ * png_get_y_offset_microns()
+ */
+#ifndef PNG_NO_EASY_ACCESS
+#define PNG_EASY_ACCESS_SUPPORTED
+#endif
+
+#ifndef PNG_NO_ASSEMBLER_CODE
+#define PNG_ASSEMBLER_CODE_SUPPORTED
+#endif
+
+/* These are currently experimental features, define them if you want */
+
+/* very little testing */
+/*
+#define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
+#define PNG_USER_MEM_SUPPORTED
+*/
+
+/* This is only for PowerPC big-endian and 680x0 systems */
+/* some testing */
+/*
+#define PNG_READ_BIG_ENDIAN_SUPPORTED
+*/
+
+/* These functions are turned off by default, as they will be phased out. */
+/*
+#define  PNG_USELESS_TESTS_SUPPORTED
+#define  PNG_CORRECT_PALETTE_SUPPORTED
+*/
+
+/* Any chunks you are not interested in, you can undef here.  The
+ * ones that allocate memory may be expecially important (hIST,
+ * tEXt, zTXt, tRNS, pCAL).  Others will just save time and make png_info
+ * a bit smaller.
+ */
+
+#if !defined(PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_READ_ANCILLARY_CHUNKS)
+#define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+#if !defined(PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
+    !defined(PNG_NO_WRITE_ANCILLARY_CHUNKS)
+#define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+#endif
+
+#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
+#ifndef PNG_NO_READ_bKGD
 #define PNG_READ_bKGD_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_cHRM
+#define PNG_READ_cHRM_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_gAMA
+#define PNG_READ_gAMA_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_hIST
 #define PNG_READ_hIST_SUPPORTED
-#define PNG_READ_pHYs_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_oFFs
 #define PNG_READ_oFFs_SUPPORTED
-#define PNG_READ_tIME_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_pCAL
+#define PNG_READ_pCAL_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_pHYs
+#define PNG_READ_pHYs_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sBIT
+#define PNG_READ_sBIT_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_sRGB
+#define PNG_READ_sRGB_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tEXt
 #define PNG_READ_tEXt_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tIME
+#define PNG_READ_tIME_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_tRNS
+#define PNG_READ_tRNS_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_zTXt
 #define PNG_READ_zTXt_SUPPORTED
-#define PNG_READ_OPT_PLTE_SUPPORTED
+#endif
+#ifndef PNG_NO_READ_OPT_PLTE
+#define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the optional */
+#endif                              /* PLTE chunk in RGB and RGBA images */
+#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */
 
-#define PNG_WRITE_gAMA_SUPPORTED
-#define PNG_WRITE_sBIT_SUPPORTED
-#define PNG_WRITE_cHRM_SUPPORTED
-#define PNG_WRITE_tRNS_SUPPORTED
+#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
+#ifndef PNG_NO_WRITE_bKGD
 #define PNG_WRITE_bKGD_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_cHRM
+#define PNG_WRITE_cHRM_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_gAMA
+#define PNG_WRITE_gAMA_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_hIST
 #define PNG_WRITE_hIST_SUPPORTED
-#define PNG_WRITE_pHYs_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_oFFs
 #define PNG_WRITE_oFFs_SUPPORTED
-#define PNG_WRITE_tIME_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_pCAL
+#define PNG_WRITE_pCAL_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_pHYs
+#define PNG_WRITE_pHYs_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_sBIT
+#define PNG_WRITE_sBIT_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_sRGB
+#define PNG_WRITE_sRGB_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_tEXt
 #define PNG_WRITE_tEXt_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_tIME
+#define PNG_WRITE_tIME_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_tRNS
+#define PNG_WRITE_tRNS_SUPPORTED
+#endif
+#ifndef PNG_NO_WRITE_zTXt
 #define PNG_WRITE_zTXt_SUPPORTED
+#endif
+#endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */
 
-/* some typedefs to get us started.  These should be safe on most of the
-   common platforms.  The typedefs should be at least as large
-   as the numbers suggest (a png_uint_32 must be at least 32 bits long),
-   but they don't have to be exactly that size. */
+/* need the time information for reading tIME chunks */
+#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
+#include <time.h>
+#endif
+
+/* Some typedefs to get us started.  These should be safe on most of the
+ * common platforms.  The typedefs should be at least as large as the
+ * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
+ * don't have to be exactly that size.  Some compilers dislike passing
+ * unsigned shorts as function parameters, so you may be better off using
+ * unsigned int for png_uint_16.  Likewise, for 64-bit systems, you may
+ * want to have unsigned int for png_uint_32 instead of unsigned long.
+ */
 
 typedef unsigned long png_uint_32;
 typedef long png_int_32;
@@ -232,21 +561,21 @@ typedef unsigned short png_uint_16;
 typedef short png_int_16;
 typedef unsigned char png_byte;
 
-/* this is usually size_t. it is typedef'ed just in case you need it to
+/* This is usually size_t.  It is typedef'ed just in case you need it to
    change (I'm not sure if you will or not, so I thought I'd be safe) */
 typedef size_t png_size_t;
 
-/* The following is needed for medium model support. It cannot be in the
-   PNG_INTERNAL section. Needs modification for other compilers besides
-   MSC. Model independent support declares all arrays that might be very
-   large using the far keyword. The Zlib version used must also support
-   model independent data. As of version Zlib .95, the necessary changes
-   have been made in Zlib. The USE_FAR_KEYWORD define triggers other
-   changes that are needed. Most of the far keyword changes are hidden
-   inside typedefs with suffix "f". Tim Wegner */
+/* The following is needed for medium model support.  It cannot be in the
+ * PNG_INTERNAL section.  Needs modification for other compilers besides
+ * MSC.  Model independent support declares all arrays and pointers to be
+ * large using the far keyword.  The zlib version used must also support
+ * model independent data.  As of version zlib 1.0.4, the necessary changes
+ * have been made in zlib.  The USE_FAR_KEYWORD define triggers other
+ * changes that are needed. (Tim Wegner)
+ */
 
-/* SJT: Separate compiler dependencies */
-/* SJT: problem here is that zlib.h always defines FAR */
+/* Separate compiler dependencies (problem here is that zlib.h always
+   defines FAR. (SJT) */
 #ifdef __BORLANDC__
 #if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
 #define LDATA 1
@@ -263,26 +592,27 @@ typedef size_t png_size_t;
 #define USE_FAR_KEYWORD
 #endif   /* LDATA != 1 */
 
-/* SJT:  Possibly useful for moving data out of default segment.
-   Uncomment it if you want. Could also define FARDATA as const
-   if your compiler supports it.
+/* Possibly useful for moving data out of default segment.
+ * Uncomment it if you want. Could also define FARDATA as
+ * const if your compiler supports it. (SJT)
 #  define FARDATA FAR
-*/
+ */
 #endif  /* __WIN32__, __FLAT__ */
 
 #endif   /* __BORLANDC__ */
 
 
-/* SJT:  Suggest testing for specific compiler first before
-   testing for FAR.  The Watcom compiler defines both __MEDIUM__
-   and M_I86MM, making reliance oncertain keywords suspect
-*/
+/* Suggest testing for specific compiler first before testing for
+ * FAR.  The Watcom compiler defines both __MEDIUM__ and M_I86MM,
+ * making reliance oncertain keywords suspect. (SJT)
+ */
 
 /* MSC Medium model */
 #if defined(FAR)
 #  if defined(M_I86MM)
 #     define USE_FAR_KEYWORD
-#     define FARDATA FAR /* SJT: added */
+#     define FARDATA FAR
+#     include <dos.h>
 #  endif
 #endif
 
@@ -291,23 +621,13 @@ typedef size_t png_size_t;
 #   define FAR
 #endif
 
-/* SJT: At this point FAR is always defined */
-
-/* not used anymore, but kept for compatability */
-typedef unsigned char FAR png_bytef;
-
-/* SJT: */
+/* At this point FAR is always defined */
 #ifndef FARDATA
 #define FARDATA
 #endif
 
-/* End medium model changes to be in zconf.h */
-
-/* SJT: More typedefs */
-typedef void FAR *   png_voidp;
-
-
-/* SJT: Add typedefs for pointers */
+/* Add typedefs for pointers */
+typedef void            FAR * png_voidp;
 typedef png_byte        FAR * png_bytep;
 typedef png_uint_32     FAR * png_uint_32p;
 typedef png_int_32      FAR * png_int_32p;
@@ -315,8 +635,9 @@ typedef png_uint_16     FAR * png_uint_16p;
 typedef png_int_16      FAR * png_int_16p;
 typedef PNG_CONST char  FAR * png_const_charp;
 typedef char            FAR * png_charp;
+typedef double          FAR * png_doublep;
 
-/*  SJT: Pointers to pointers; i.e. arrays */
+/* Pointers to pointers; i.e. arrays */
 typedef png_byte        FAR * FAR * png_bytepp;
 typedef png_uint_32     FAR * FAR * png_uint_32pp;
 typedef png_int_32      FAR * FAR * png_int_32pp;
@@ -324,37 +645,80 @@ typedef png_uint_16     FAR * FAR * png_uint_16pp;
 typedef png_int_16      FAR * FAR * png_int_16pp;
 typedef PNG_CONST char  FAR * FAR * png_const_charpp;
 typedef char            FAR * FAR * png_charpp;
+typedef double          FAR * FAR * png_doublepp;
 
+/* Pointers to pointers to pointers; i.e. pointer to array */
+typedef char            FAR * FAR * FAR * png_charppp;
 
-/* SJT: libpng typedefs for types in zlib. If Zlib changes
-   or another compression library is used, then change these.
-   Eliminates need to change all the source files.
-*/
+/* libpng typedefs for types in zlib. If zlib changes
+ * or another compression library is used, then change these.
+ * Eliminates need to change all the source files.
+ */
 typedef charf *         png_zcharp;
 typedef charf * FAR *   png_zcharpp;
-typedef z_stream *      png_zstreamp; /* zlib won't accept far z_stream */
+typedef z_stream FAR *  png_zstreamp;
+
+
+#ifndef PNG_EXPORT
+   /* allow for compilation as dll under MS Windows */
+#  ifdef __WIN32DLL__
+#    define PNG_EXPORT(type,symbol) __declspec(dllexport) type symbol
+#  endif
+
+   /* this variant is used in Mozilla; may correspond to MSVC++ 6.0 changes */
+#  ifdef ALT_WIN32_DLL
+#    define PNG_EXPORT(type,symbol) type __attribute__((dllexport)) symbol
+#  endif
+
+   /* allow for compilation as dll with Borland C++ 5.0 */
+#  if defined(__BORLANDC__) && defined(_Windows) && defined(__DLL__)
+#    define PNG_EXPORT(type,symbol) type _export symbol
+#  endif
+
+   /* allow for compilation as shared lib under BeOS */
+#  ifdef __BEOSDLL__
+#    define PNG_EXPORT(type,symbol) __declspec(export) type symbol
+#  endif
+#endif
+
+#ifndef PNG_EXPORT
+#  define PNG_EXPORT(type,symbol) type symbol
+#endif
 
 
 /* User may want to use these so not in PNG_INTERNAL. Any library functions
-   that are passed far data must be model independent. */
+ * that are passed far data must be model independent.
+ */
+
 #if defined(USE_FAR_KEYWORD)  /* memory model independent fns */
+/* use this to make far-to-near assignments */
+#   define CHECK   1
+#   define NOCHECK 0
+#   define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
+#   define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
 #   define png_strcpy _fstrcpy
-#   define png_strcat _fstrcat
 #   define png_strlen _fstrlen
-#   define png_strcmp _fstrcmp
 #   define png_memcmp _fmemcmp      /* SJT: added */
 #   define png_memcpy _fmemcpy
 #   define png_memset _fmemset
 #else /* use the usual functions */
+#   define CVT_PTR(ptr)         (ptr)
+#   define CVT_PTR_NOCHECK(ptr) (ptr)
 #   define png_strcpy strcpy
-#   define png_strcat strcat
 #   define png_strlen strlen
-#   define png_strcmp strcmp
 #   define png_memcmp memcmp     /* SJT: added */
 #   define png_memcpy memcpy
 #   define png_memset memset
 #endif
 /* End of memory model independent support */
 
+/* Just a double check that someone hasn't tried to define something
+ * contradictory.
+ */
+#if (PNG_ZBUF_SIZE > 65536) && defined(PNG_MAX_MALLOC_64K)
+#undef PNG_ZBUF_SIZE
+#define PNG_ZBUF_SIZE 65536
+#endif
+
 #endif /* PNGCONF_H */
 

pngerror.c

@@ -1,15 +1,17 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-
-   This file provides a location for all error handling.  Users which
-   need special error handling are expected to write replacement functions
-   and use png_set_error_fn() to use those functions.  See the instructions
-   at each function. */
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ *
+ * This file provides a location for all error handling.  Users who
+ * need special error handling are expected to write replacement functions
+ * and use png_set_error_fn() to use those functions.  See the instructions
+ * at each function.
+ */
 
 #define PNG_INTERNAL
 #include "png.h"
@@ -20,13 +22,14 @@ static void png_default_warning PNGARG((png_structp png_ptr,
                                         png_const_charp message));
 
 /* 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,
-   you should supply a replacement error function and use png_set_error_fn()
-   to replace the error function at run-time. */
+ * should not be changed.  If there is a need to handle errors differently,
+ * you should supply a replacement error function and use png_set_error_fn()
+ * to replace the error function at run-time.
+ */
 void
 png_error(png_structp png_ptr, png_const_charp message)
 {
-   if (png_ptr->error_fn)
+   if (png_ptr->error_fn != NULL)
       (*(png_ptr->error_fn))(png_ptr, message);
 
    /* if the following returns or doesn't exist, use the default function,
@@ -35,26 +38,82 @@ png_error(png_structp png_ptr, png_const_charp message)
 }
 
 /* This function is called whenever there is a non-fatal error.  This function
-   should not be changed.  If there is a need to handle warnings differently,
-   you should supply a replacement warning function and use
-   png_set_error_fn() to replace the warning function at run-time. */
+ * should not be changed.  If there is a need to handle warnings differently,
+ * you should supply a replacement warning function and use
+ * png_set_error_fn() to replace the warning function at run-time.
+ */
 void
 png_warning(png_structp png_ptr, png_const_charp message)
 {
-   if (png_ptr->warning_fn)
+   if (png_ptr->warning_fn != NULL)
       (*(png_ptr->warning_fn))(png_ptr, message);
    else
       png_default_warning(png_ptr, message);
 }
 
+/* These utilities are used internally to build an error message that relates
+ * to the current chunk.  The chunk name comes from png_ptr->chunk_name,
+ * this is used to prefix the message.  The message is limited in length
+ * to 63 bytes, the name characters are output as hex digits wrapped in []
+ * if the character is invalid.
+ */
+#define isnonalpha(c) ((c) < 41 || (c) > 122 || ((c) > 90 && (c) < 97))
+static PNG_CONST char png_digit[16] = {
+   '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
+};
+
+static void
+png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp message)
+{
+   int iout = 0, iin = 0;
+
+   while (iin < 4) {
+      int c = png_ptr->chunk_name[iin++];
+      if (isnonalpha(c)) {
+         buffer[iout++] = '[';
+         buffer[iout++] = png_digit[(c & 0xf0) >> 4];
+         buffer[iout++] = png_digit[c & 0xf];
+         buffer[iout++] = ']';
+      } else {
+         buffer[iout++] = c;
+      }
+   }
+
+   if (message == NULL)
+      buffer[iout] = 0;
+   else {
+      buffer[iout++] = ':';
+      buffer[iout++] = ' ';
+      png_memcpy(buffer+iout, message, 64);
+      buffer[iout+63] = 0;
+   }
+}
+
+void
+png_chunk_error(png_structp png_ptr, png_const_charp message)
+{
+   char msg[16+64];
+   png_format_buffer(png_ptr, msg, message);
+   png_error(png_ptr, msg);
+}
+
+void
+png_chunk_warning(png_structp png_ptr, png_const_charp message)
+{
+   char msg[16+64];
+   png_format_buffer(png_ptr, msg, message);
+   png_warning(png_ptr, msg);
+}
+
 /* This is the default error handling function.  Note that replacements for
-   this function MUST NOT RETURN, or the program will likely crash.  This
-   function is used by default, or if the program supplies NULL for the
-   error function pointer in png_set_error_fn(). */
+ * this function MUST NOT RETURN, or the program will likely crash.  This
+ * function is used by default, or if the program supplies NULL for the
+ * error function pointer in png_set_error_fn().
+ */
 static void
 png_default_error(png_structp png_ptr, png_const_charp message)
 {
-#ifndef PNG_NO_STDIO
+#ifndef PNG_NO_CONSOLE_IO
    fprintf(stderr, "libpng error: %s\n", message);
 #endif
 
@@ -70,24 +129,25 @@ png_default_error(png_structp png_ptr, png_const_charp message)
 }
 
 /* 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
-   here if you don't want to.  In the default configuration, png_ptr is
-   not used, but it is passed in case it may be useful. */
+ * it can continue anyway.  Replacement functions don't have to do anything
+ * here if you don't want them to.  In the default configuration, png_ptr is
+ * not used, but it is passed in case it may be useful.
+ */
 static void
 png_default_warning(png_structp png_ptr, png_const_charp message)
 {
-   if (!png_ptr)
-      return;
-
-#ifndef PNG_NO_STDIO
+#ifndef PNG_NO_CONSOLE_IO
    fprintf(stderr, "libpng warning: %s\n", message);
 #endif
+   if (png_ptr == NULL)
+      return;
 }
 
 /* This function is called when the application wants to use another method
-   of handling errors and warnings.  Note that the error function MUST NOT
-   return to the calling routine or serious problems will occur.  The return
-   method used in the default routine calls longjmp(png_ptr->jmpbuf, 1) */
+ * of handling errors and warnings.  Note that the error function MUST NOT
+ * return to the calling routine or serious problems will occur.  The return
+ * method used in the default routine calls longjmp(png_ptr->jmpbuf, 1)
+ */
 void
 png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
    png_error_ptr error_fn, png_error_ptr warning_fn)
@@ -99,12 +159,13 @@ png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
 
 
 /* This function returns a pointer to the error_ptr associated with the user
-   functions.  The application should free any memory associated with this
-   pointer before png_write_destroy and png_read_destroy are called. */
+ * functions.  The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
 png_voidp
 png_get_error_ptr(png_structp png_ptr)
 {
-   return png_ptr->error_ptr;
+   return ((png_voidp)png_ptr->error_ptr);
 }
 
 

pngget.c

@@ -0,0 +1,650 @@
+
+/* pngget.c - retrieval of values from info struct
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+png_uint_32
+png_get_valid(png_structp png_ptr, png_infop info_ptr, png_uint_32 flag)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->valid & flag);
+   else
+      return(0);
+}
+
+png_uint_32
+png_get_rowbytes(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->rowbytes);
+   else
+      return(0);
+}
+
+#ifdef PNG_EASY_ACCESS_SUPPORTED
+/* easy access to info, added in libpng-0.99 */
+png_uint_32
+png_get_image_width(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->width;
+   }
+   return (0);
+}
+
+png_uint_32
+png_get_image_height(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->height;
+   }
+   return (0);
+}
+
+png_byte
+png_get_bit_depth(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->bit_depth;
+   }
+   return (0);
+}
+
+png_byte
+png_get_color_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->color_type;
+   }
+   return (0);
+}
+
+png_byte
+png_get_filter_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->filter_type;
+   }
+   return (0);
+}
+
+png_byte
+png_get_interlace_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->interlace_type;
+   }
+   return (0);
+}
+
+png_byte
+png_get_compression_type(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+   {
+      return info_ptr->compression_type;
+   }
+   return (0);
+}
+
+png_uint_32
+png_get_x_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+          return (0);
+      else return (info_ptr->x_pixels_per_unit);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_y_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER)
+          return (0);
+      else return (info_ptr->y_pixels_per_unit);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_pixels_per_meter(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_pixels_per_meter");
+      if(info_ptr->phys_unit_type != PNG_RESOLUTION_METER ||
+         info_ptr->x_pixels_per_unit != info_ptr->y_pixels_per_unit)
+          return (0);
+      else return (info_ptr->x_pixels_per_unit);
+   }
+   else
+#endif
+   return (0);
+}
+
+float
+png_get_pixel_aspect_ratio(png_structp png_ptr, png_infop info_ptr)
+   {
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_aspect_ratio");
+      if (info_ptr->x_pixels_per_unit == 0)
+         return ((float)0.0);
+      else
+         return ((float)info_ptr->y_pixels_per_unit
+            /(float)info_ptr->x_pixels_per_unit);
+   }
+   else
+#endif
+      return ((float)0.0);
+}
+
+png_uint_32
+png_get_x_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+          return (0);
+      else return (info_ptr->x_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_y_offset_microns(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_MICROMETER)
+          return (0);
+      else return (info_ptr->y_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_x_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_x_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+          return (0);
+      else return (info_ptr->x_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+png_uint_32
+png_get_y_offset_pixels(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
+   {
+      png_debug1(1, "in %s retrieval function\n", "png_get_y_offset_microns");
+      if(info_ptr->offset_unit_type != PNG_OFFSET_PIXEL)
+          return (0);
+      else return (info_ptr->y_offset);
+   }
+   else
+#endif
+   return (0);
+}
+
+#ifdef PNG_INCH_CONVERSIONS
+png_uint_32
+png_get_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_pixels_per_meter(png_ptr, info_ptr)
+     *.03937 +.5)
+}
+
+png_uint_32
+png_get_x_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_x_pixels_per_meter(png_ptr, info_ptr)
+     *.03937 +.5)
+}
+
+png_uint_32
+png_get_y_pixels_per_inch(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((png_uint_32)((float)png_get_y_pixels_per_meter(png_ptr, info_ptr)
+     *.03937 +.5)
+}
+
+float
+png_get_x_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((float)png_get_x_offset_microns(png_ptr, info_ptr)
+     *.03937/1000000. +.5)
+}
+
+float
+png_get_y_offset_inches(png_structp png_ptr, png_infop info_ptr)
+{
+   return ((float)png_get_y_offset_microns(png_ptr, info_ptr)
+     *.03937/1000000. +.5)
+}
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+png_uint_32
+png_get_pHYs_dpi(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+   png_uint_32 retval = 0;
+
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "pHYs");
+      if (res_x != NULL)
+      {
+         *res_x = info_ptr->x_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (res_y != NULL)
+      {
+         *res_y = info_ptr->y_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (unit_type != NULL)
+      {
+         *unit_type = (int)info_ptr->phys_unit_type;
+         retval |= PNG_INFO_pHYs;
+         if(unit_type == 1)
+         {
+            if (res_x != NULL) *res_x = (png_uint_32)(*res_x * 39.37 + .50);
+            if (res_y != NULL) *res_y = (png_uint_32)(*res_y * 39.37 + .50);
+         }
+      }
+   }
+   return (retval);
+}
+#endif /* PNG_READ_pHYs_SUPPORTED */
+#endif  /* PNG_INCH_CONVERSIONS */
+
+/* png_get_channels really belongs in here, too, but it's been around longer */
+
+#endif  /* PNG_EASY_ACCESS_SUPPORTED */
+
+png_byte
+png_get_channels(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->channels);
+   else
+      return (0);
+}
+
+png_bytep
+png_get_signature(png_structp png_ptr, png_infop info_ptr)
+{
+   if (png_ptr != NULL && info_ptr != NULL)
+      return(info_ptr->signature);
+   else
+      return (NULL);
+}
+
+#if defined(PNG_READ_bKGD_SUPPORTED)
+png_uint_32
+png_get_bKGD(png_structp png_ptr, png_infop info_ptr,
+   png_color_16p *background)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD)
+      && background != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "bKGD");
+      *background = &(info_ptr->background);
+      return (PNG_INFO_bKGD);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED)
+png_uint_32
+png_get_cHRM(png_structp png_ptr, png_infop info_ptr,
+   double *white_x, double *white_y, double *red_x, double *red_y,
+   double *green_x, double *green_y, double *blue_x, double *blue_y)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
+   {
+      png_debug1(1, "in %s retrieval function\n", "cHRM");
+      if (white_x != NULL)
+         *white_x = (double)info_ptr->x_white;
+      if (white_y != NULL)
+         *white_y = (double)info_ptr->y_white;
+      if (red_x != NULL)
+         *red_x = (double)info_ptr->x_red;
+      if (red_y != NULL)
+         *red_y = (double)info_ptr->y_red;
+      if (green_x != NULL)
+         *green_x = (double)info_ptr->x_green;
+      if (green_y != NULL)
+         *green_y = (double)info_ptr->y_green;
+      if (blue_x != NULL)
+         *blue_x = (double)info_ptr->x_blue;
+      if (blue_y != NULL)
+         *blue_y = (double)info_ptr->y_blue;
+      return (PNG_INFO_cHRM);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_gAMA_SUPPORTED)
+png_uint_32
+png_get_gAMA(png_structp png_ptr, png_infop info_ptr, double *file_gamma)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
+      && file_gamma != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "gAMA");
+      *file_gamma = (double)info_ptr->gamma;
+      return (PNG_INFO_gAMA);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_sRGB_SUPPORTED)
+png_uint_32
+png_get_sRGB(png_structp png_ptr, png_infop info_ptr, int *file_srgb_intent)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB)
+      && file_srgb_intent != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "sRGB");
+      *file_srgb_intent = (int)info_ptr->srgb_intent;
+      return (PNG_INFO_sRGB);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_hIST_SUPPORTED)
+png_uint_32
+png_get_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p *hist)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST)
+      && hist != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "hIST");
+      *hist = info_ptr->hist;
+      return (PNG_INFO_hIST);
+   }
+   return (0);
+}
+#endif
+
+png_uint_32
+png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *width, png_uint_32 *height, int *bit_depth,
+   int *color_type, int *interlace_type, int *compression_type,
+   int *filter_type)
+
+{
+   if (png_ptr != NULL && info_ptr != NULL && width != NULL && height != NULL &&
+      bit_depth != NULL && color_type != NULL)
+   {
+      int pixel_depth, channels;
+      png_uint_32 rowbytes_per_pixel;
+
+      png_debug1(1, "in %s retrieval function\n", "IHDR");
+      *width = info_ptr->width;
+      *height = info_ptr->height;
+      *bit_depth = info_ptr->bit_depth;
+      *color_type = info_ptr->color_type;
+      if (compression_type != NULL)
+         *compression_type = info_ptr->compression_type;
+      if (filter_type != NULL)
+         *filter_type = info_ptr->filter_type;
+      if (interlace_type != NULL)
+         *interlace_type = info_ptr->interlace_type;
+
+      /* check for potential overflow of rowbytes */
+      if (*color_type == PNG_COLOR_TYPE_PALETTE)
+         channels = 1;
+      else if (*color_type & PNG_COLOR_MASK_COLOR)
+         channels = 3;
+      else
+         channels = 1;
+      if (*color_type & PNG_COLOR_MASK_ALPHA)
+         channels++;
+      pixel_depth = *bit_depth * channels;
+      rowbytes_per_pixel = (pixel_depth + 7) >> 3;
+      if ((*width > PNG_MAX_UINT/rowbytes_per_pixel))
+      {
+         png_warning(png_ptr,
+            "Width too large for libpng to process image data.");
+      }
+      return (1);
+   }
+   return (0);
+}
+
+#if defined(PNG_READ_oFFs_SUPPORTED)
+png_uint_32
+png_get_oFFs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *offset_x, png_uint_32 *offset_y, int *unit_type)
+{
+   if (png_ptr != NULL && info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs)
+      && offset_x != NULL && offset_y != NULL && unit_type != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "oFFs");
+      *offset_x = info_ptr->x_offset;
+      *offset_y = info_ptr->y_offset;
+      *unit_type = (int)info_ptr->offset_unit_type;
+      return (PNG_INFO_oFFs);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_pCAL_SUPPORTED)
+png_uint_32
+png_get_pCAL(png_structp png_ptr, png_infop info_ptr,
+   png_charp *purpose, png_int_32 *X0, png_int_32 *X1, int *type, int *nparams,
+   png_charp *units, png_charpp *params)
+{
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pCAL &&
+      purpose != NULL && X0 != NULL && X1 != NULL && type != NULL &&
+      nparams != NULL && units != NULL && params != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "pCAL");
+      *purpose = info_ptr->pcal_purpose;
+      *X0 = info_ptr->pcal_X0;
+      *X1 = info_ptr->pcal_X1;
+      *type = (int)info_ptr->pcal_type;
+      *nparams = (int)info_ptr->pcal_nparams;
+      *units = info_ptr->pcal_units;
+      *params = info_ptr->pcal_params;
+      return (PNG_INFO_pCAL);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_pHYs_SUPPORTED)
+png_uint_32
+png_get_pHYs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 *res_x, png_uint_32 *res_y, int *unit_type)
+{
+   png_uint_32 retval = 0;
+
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_pHYs)
+   {
+      png_debug1(1, "in %s retrieval function\n", "pHYs");
+      if (res_x != NULL)
+      {
+         *res_x = info_ptr->x_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (res_y != NULL)
+      {
+         *res_y = info_ptr->y_pixels_per_unit;
+         retval |= PNG_INFO_pHYs;
+      }
+      if (unit_type != NULL)
+      {
+         *unit_type = (int)info_ptr->phys_unit_type;
+         retval |= PNG_INFO_pHYs;
+      }
+   }
+   return (retval);
+}
+#endif
+
+png_uint_32
+png_get_PLTE(png_structp png_ptr, png_infop info_ptr, png_colorp *palette,
+   int *num_palette)
+{
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_PLTE &&
+       palette != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "PLTE");
+      *palette = info_ptr->palette;
+      *num_palette = info_ptr->num_palette;
+      png_debug1(3, "num_palette = %d\n", *num_palette);
+      return (PNG_INFO_PLTE);
+   }
+   return (0);
+}
+
+#if defined(PNG_READ_sBIT_SUPPORTED)
+png_uint_32
+png_get_sBIT(png_structp png_ptr, png_infop info_ptr, png_color_8p *sig_bit)
+{
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_sBIT &&
+       sig_bit != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "sBIT");
+      *sig_bit = &(info_ptr->sig_bit);
+      return (PNG_INFO_sBIT);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
+png_uint_32
+png_get_text(png_structp png_ptr, png_infop info_ptr, png_textp *text_ptr,
+   int *num_text)
+{
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->num_text > 0)
+   {
+      png_debug1(1, "in %s retrieval function\n",
+         (png_ptr->chunk_name[0] == '\0' ? "text"
+             : (png_const_charp)png_ptr->chunk_name));
+      if (text_ptr != NULL)
+         *text_ptr = info_ptr->text;
+      if (num_text != NULL)
+         *num_text = info_ptr->num_text;
+      return ((png_uint_32)info_ptr->num_text);
+   }
+   return(0);
+}
+#endif
+
+#if defined(PNG_READ_tIME_SUPPORTED)
+png_uint_32
+png_get_tIME(png_structp png_ptr, png_infop info_ptr, png_timep *mod_time)
+{
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_tIME &&
+       mod_time != NULL)
+   {
+      png_debug1(1, "in %s retrieval function\n", "tIME");
+      *mod_time = &(info_ptr->mod_time);
+      return (PNG_INFO_tIME);
+   }
+   return (0);
+}
+#endif
+
+#if defined(PNG_READ_tRNS_SUPPORTED)
+png_uint_32
+png_get_tRNS(png_structp png_ptr, png_infop info_ptr,
+   png_bytep *trans, int *num_trans, png_color_16p *trans_values)
+{
+   png_uint_32 retval = 0;
+   if (png_ptr != NULL && info_ptr != NULL && info_ptr->valid & PNG_INFO_tRNS)
+   {
+      png_debug1(1, "in %s retrieval function\n", "tRNS");
+      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      {
+          if (trans != NULL)
+          {
+             *trans = info_ptr->trans;
+             retval |= PNG_INFO_tRNS;
+          }
+          if (trans_values != NULL)
+             *trans_values = &(info_ptr->trans_values);
+      }
+      else /* if (info_ptr->color_type != PNG_COLOR_TYPE_PALETTE) */
+      {
+          if (trans_values != NULL)
+          {
+             *trans_values = &(info_ptr->trans_values);
+             retval |= PNG_INFO_tRNS;
+          }
+          if(trans != NULL)
+             *trans = NULL;
+      }
+      if(num_trans != NULL)
+      {
+         *num_trans = info_ptr->num_trans;
+         retval |= PNG_INFO_tRNS;
+      }
+   }
+   return (retval);
+}
+#endif
+
+#if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
+png_byte
+png_get_rgb_to_gray_status (png_structp png_ptr)
+{
+   return png_ptr->rgb_to_gray_status;
+}
+#endif

pngmem.c

@@ -1,14 +1,18 @@
 
 /* pngmem.c - stub functions for memory allocation
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-
-   This file provides a location for all memory allocation.  Users which
-   need special memory handling are expected to modify the code in this file
-   to meet their needs.  See the instructions at each function. */
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ *
+ * This file provides a location for all memory allocation.  Users who
+ * need special memory handling are expected to supply replacement
+ * functions for png_malloc() and png_free(), and to use
+ * png_create_read_struct_2() and png_create_write_struct_2() to
+ * identify the replacement functions.
+ */
 
 #define PNG_INTERNAL
 #include "png.h"
@@ -18,12 +22,20 @@
 /* if you change this, be sure to change the one in png.h also */
 
 /* Allocate memory for a png_struct.  The malloc and memset can be replaced
- * by a single call to calloc() if this is thought to improve performance.
- */
+   by a single call to calloc() if this is thought to improve performance. */
 png_voidp
-png_create_struct(uInt type)
+png_create_struct(int type)
 {
-   png_size_t type;
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_struct_2(type, NULL));
+}
+
+/* Alternate version of png_create_struct, for use with user-defined malloc. */
+png_voidp
+png_create_struct_2(int type, png_malloc_ptr malloc_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_size_t size;
    png_voidp struct_ptr;
 
    if (type == PNG_STRUCT_INFO)
@@ -31,13 +43,20 @@ png_create_struct(uInt type)
    else if (type == PNG_STRUCT_PNG)
      size = sizeof(png_struct);
    else
-     return (png_voidp)NULL;
+     return ((png_voidp)NULL);
 
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(malloc_fn != NULL)
+   {
+      if ((struct_ptr = (*(malloc_fn))(NULL, size)) != NULL)
+         png_memset(struct_ptr, 0, size);
+         return (struct_ptr);
+   }
+#endif /* PNG_USER_MEM_SUPPORTED */
    if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
    {
       png_memset(struct_ptr, 0, size);
    }
-
    return (struct_ptr);
 }
 
@@ -46,44 +65,85 @@ png_create_struct(uInt type)
 void
 png_destroy_struct(png_voidp struct_ptr)
 {
-   if (struct_ptr)
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_destroy_struct_2(struct_ptr, (png_free_ptr)NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
+{
+#endif
+   if (struct_ptr != NULL)
+   {
+#ifdef PNG_USER_MEM_SUPPORTED
+      if(free_fn != NULL)
+      {
+         png_struct dummy_struct;
+         png_structp png_ptr = &dummy_struct;
+         (*(free_fn))(png_ptr, struct_ptr);
+         struct_ptr = NULL;
+         return;
+      }
+#endif /* PNG_USER_MEM_SUPPORTED */
       farfree (struct_ptr);
+      struct_ptr = NULL;
+   }
 }
 
 /* Allocate memory.  For reasonable files, size should never exceed
-   64K.  However, zlib may allocate more then 64K if you don't tell
-   it not to.  See zconf.h and png.h for more information. zlib does
-   need to allocate exactly 64K, so whatever you call here must
-   have the ability to do that. */
+ * 64K.  However, zlib may allocate more then 64K if you don't tell
+ * it not to.  See zconf.h and png.h for more information. zlib does
+ * need to allocate exactly 64K, so whatever you call here must
+ * have the ability to do that.
+ *
+ * Borland seems to have a problem in DOS mode for exactly 64K.
+ * It gives you a segment with an offset of 8 (perhaps to store its
+ * memory stuff).  zlib doesn't like this at all, so we have to
+ * detect and deal with it.  This code should not be needed in
+ * Windows or OS/2 modes, and only in 16 bit mode.  This code has
+ * been updated by Alexander Lehmann for version 0.89 to waste less
+ * memory.
+ *
+ * Note that we can't use png_size_t for the "size" declaration,
+ * since on some systems a png_size_t is a 16-bit quantity, and as a
+ * result, we would be truncating potentially larger memory requests
+ * (which should cause a fatal error) and introducing major problems.
+ */
+png_voidp
+png_malloc(png_structp png_ptr, png_uint_32 size)
+{
+#ifndef PNG_USER_MEM_SUPPORTED
+   png_voidp ret;
+#endif
+   if (png_ptr == NULL || size == 0)
+      return ((png_voidp)NULL);
 
-/* Borland seems to have a problem in DOS mode for exactly 64K.
-   It gives you a segment with an offset of 8 (perhaps to store it's
-   memory stuff).  zlib doesn't like this at all, so we have to
-   detect and deal with it.  This code should not be needed in
-   Windows or OS/2 modes, and only in 16 bit mode.  This code has
-   been updated by Alexander Lehmann for version 0.89 to waste less
-   memory.
-*/
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(png_ptr->malloc_fn != NULL)
+       return ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
+   else
+       return png_malloc_default(png_ptr, size);
+}
 
 png_voidp
-png_large_malloc(png_structp png_ptr, png_uint_32 size)
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
 {
    png_voidp ret;
-   if (!png_ptr || !size)
-      return ((voidp)NULL);
+#endif /* PNG_USER_MEM_SUPPORTED */
 
 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)
       png_error(png_ptr, "Cannot Allocate > 64K");
 #endif
 
-   if (size == (png_uint_32)(65536L))
+   if (size == (png_uint_32)65536L)
    {
-      if (!png_ptr->offset_table)
+      if (png_ptr->offset_table == NULL)
       {
          /* try to see if we need to do any of this fancy stuff */
          ret = farmalloc(size);
-         if (!ret || ((long)ret & 0xffff))
+         if (ret == NULL || ((png_size_t)ret & 0xffff))
          {
             int num_blocks;
             png_uint_32 total_size;
@@ -91,12 +151,15 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
             int i;
             png_byte huge * hptr;
 
-            if (ret)
+            if (ret != NULL)
+            {
                farfree(ret);
-            ret = NULL;
+               ret = NULL;
+            }
 
-            num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
-            if (num_blocks < 1)
+            if(png_ptr->zlib_window_bits > 14)
+               num_blocks = (int)(1 << (png_ptr->zlib_window_bits - 14));
+            else
                num_blocks = 1;
             if (png_ptr->zlib_mem_level >= 7)
                num_blocks += (int)(1 << (png_ptr->zlib_mem_level - 7));
@@ -107,35 +170,35 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
 
             table = farmalloc(total_size);
 
-            if (!table)
+            if (table == NULL)
             {
-               png_error(png_ptr, "Out of Memory");
+               png_error(png_ptr, "Out Of Memory."); /* Note "O" and "M" */
             }
 
-            if ((long)table & 0xfff0)
+            if ((png_size_t)table & 0xfff0)
             {
                png_error(png_ptr, "Farmalloc didn't return normalized pointer");
             }
 
             png_ptr->offset_table = table;
-            png_ptr->offset_table_ptr = farmalloc(
-               num_blocks * sizeof (png_bytep));
+            png_ptr->offset_table_ptr = farmalloc(num_blocks *
+               sizeof (png_bytep));
 
-            if (!png_ptr->offset_table_ptr)
+            if (png_ptr->offset_table_ptr == NULL)
             {
-               png_error(png_ptr, "Out of memory");
+               png_error(png_ptr, "Out Of memory.");
             }
 
             hptr = (png_byte huge *)table;
-            if ((long)hptr & 0xf)
+            if ((png_size_t)hptr & 0xf)
             {
                hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
-               hptr += 16L;
+               hptr = hptr + 16L;  /* "hptr += 16L" fails on Turbo C++ 3.0 */
             }
             for (i = 0; i < num_blocks; i++)
             {
                png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
-               hptr += 65536L;
+               hptr = hptr + (png_uint_32)65536L;  /* "+=" fails on TC++3.0 */
             }
 
             png_ptr->offset_table_number = num_blocks;
@@ -145,7 +208,7 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
       }
 
       if (png_ptr->offset_table_count >= png_ptr->offset_table_number)
-         png_error(png_ptr, "Out of Memory");
+         png_error(png_ptr, "Out of Memory.");
 
       ret = png_ptr->offset_table_ptr[png_ptr->offset_table_count++];
    }
@@ -154,74 +217,108 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
 
    if (ret == NULL)
    {
-      png_error(png_ptr, "Out of Memory");
+      png_error(png_ptr, "Out of memory."); /* Note "o" and "m" */
    }
 
-   return ret;
+   return (ret);
 }
 
-/* free a pointer allocated by png_large_malloc().  In the default
-  configuration, png_ptr is not used, but is passed in case it
-  is needed.  If ptr is NULL, return without taking any action. */
+/* free a pointer allocated by png_malloc().  In the default
+   configuration, png_ptr is not used, but is passed in case it
+   is needed.  If ptr is NULL, return without taking any action. */
 void
-png_large_free(png_structp png_ptr, png_voidp ptr)
+png_free(png_structp png_ptr, png_voidp ptr)
 {
-   if (!png_ptr)
+   if (png_ptr == NULL || ptr == NULL)
       return;
 
+#ifdef PNG_USER_MEM_SUPPORTED
+   if (png_ptr->free_fn != NULL)
+   {
+      (*(png_ptr->free_fn))(png_ptr, ptr);
+      ptr = NULL;
+      return;
+   }
+   else png_free_default(png_ptr, ptr);
+}
+
+void
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
+   if (png_ptr->offset_table != NULL)
+   {
+      int i;
+
+      for (i = 0; i < png_ptr->offset_table_count; i++)
+      {
+         if (ptr == png_ptr->offset_table_ptr[i])
+         {
+            ptr = NULL;
+            png_ptr->offset_table_count_free++;
+            break;
+         }
+      }
+      if (png_ptr->offset_table_count_free == png_ptr->offset_table_count)
+      {
+         farfree(png_ptr->offset_table);
+         farfree(png_ptr->offset_table_ptr);
+         png_ptr->offset_table = NULL;
+         png_ptr->offset_table_ptr = NULL;
+      }
+   }
+
    if (ptr != NULL)
    {
-      if (png_ptr->offset_table)
-      {
-         int i;
-
-         for (i = 0; i < png_ptr->offset_table_count; i++)
-         {
-            if (ptr == png_ptr->offset_table_ptr[i])
-            {
-               ptr = 0;
-               png_ptr->offset_table_count_free++;
-               break;
-            }
-         }
-         if (png_ptr->offset_table_count_free == png_ptr->offset_table_count)
-         {
-            farfree(png_ptr->offset_table);
-            farfree(png_ptr->offset_table_ptr);
-            png_ptr->offset_table = 0;
-            png_ptr->offset_table_ptr = 0;
-         }
-      }
-
-      if (ptr)
-         farfree(ptr);
+      farfree(ptr);
+      ptr = NULL;
    }
 }
 
 #else /* Not the Borland DOS special memory handler */
 
 /* Allocate memory for a png_struct or a png_info.  The malloc and
- * memset can be replaced by a single call to calloc() if this is thought
- * to improve performance noticably.
- */
+   memset can be replaced by a single call to calloc() if this is thought
+   to improve performance noticably.*/
 png_voidp
-png_create_struct(uInt type)
+png_create_struct(int type)
 {
-   size_t size;
+#ifdef PNG_USER_MEM_SUPPORTED
+   return (png_create_struct_2(type, NULL));
+}
+
+/* Allocate memory for a png_struct or a png_info.  The malloc and
+   memset can be replaced by a single call to calloc() if this is thought
+   to improve performance noticably.*/
+png_voidp
+png_create_struct_2(int type, png_malloc_ptr malloc_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   png_size_t size;
    png_voidp struct_ptr;
 
    if (type == PNG_STRUCT_INFO)
-     size = sizeof(png_info);
+      size = sizeof(png_info);
    else if (type == PNG_STRUCT_PNG)
-     size = sizeof(png_struct);
+      size = sizeof(png_struct);
    else
-     return (png_voidp)NULL;
+      return ((png_voidp)NULL);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(malloc_fn != NULL)
+   {
+      if ((struct_ptr = (*(malloc_fn))(NULL, size)) != NULL)
+         png_memset(struct_ptr, 0, size);
+      return (struct_ptr);
+   }
+#endif /* PNG_USER_MEM_SUPPORTED */
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
    if ((struct_ptr = (png_voidp)farmalloc(size)) != NULL)
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
-   if ((struct_ptr = (png_voidp)halloc(size)) != NULL)
+   if ((struct_ptr = (png_voidp)halloc(size,1)) != NULL)
 # else
    if ((struct_ptr = (png_voidp)malloc(size)) != NULL)
 # endif
@@ -238,31 +335,69 @@ png_create_struct(uInt type)
 void
 png_destroy_struct(png_voidp struct_ptr)
 {
-   if (struct_ptr)
+#ifdef PNG_USER_MEM_SUPPORTED
+   png_destroy_struct_2(struct_ptr, (png_free_ptr)NULL);
+}
+
+/* Free memory allocated by a png_create_struct() call */
+void
+png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+   if (struct_ptr != NULL)
+   {
+#ifdef PNG_USER_MEM_SUPPORTED
+      if(free_fn != NULL)
+      {
+         png_struct dummy_struct;
+         png_structp png_ptr = &dummy_struct;
+         (*(free_fn))(png_ptr, struct_ptr);
+         struct_ptr = NULL;
+         return;
+      }
+#endif /* PNG_USER_MEM_SUPPORTED */
 #if defined(__TURBOC__) && !defined(__FLAT__)
       farfree(struct_ptr);
+      struct_ptr = NULL;
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
       hfree(struct_ptr);
+      struct_ptr = NULL;
 # else
       free(struct_ptr);
+      struct_ptr = NULL;
 # endif
 #endif
+   }
 }
 
 
 /* Allocate memory.  For reasonable files, size should never exceed
    64K.  However, zlib may allocate more then 64K if you don't tell
-   it not to.  See zconf.h and png.h for more information. zlib does
+   it not to.  See zconf.h and png.h for more information.  zlib does
    need to allocate exactly 64K, so whatever you call here must
    have the ability to do that. */
 
 png_voidp
-png_large_malloc(png_structp png_ptr, png_uint_32 size)
+png_malloc(png_structp png_ptr, png_uint_32 size)
+{
+#ifndef PNG_USER_MEM_SUPPORTED
+   png_voidp ret;
+#endif
+   if (png_ptr == NULL || size == 0)
+      return ((png_voidp)NULL);
+
+#ifdef PNG_USER_MEM_SUPPORTED
+   if(png_ptr->malloc_fn != NULL)
+       return ((png_voidp)(*(png_ptr->malloc_fn))(png_ptr, size));
+   else
+       return (png_malloc_default(png_ptr, size));
+}
+png_voidp
+png_malloc_default(png_structp png_ptr, png_uint_32 size)
 {
    png_voidp ret;
-   if (!png_ptr || !size)
-      return ((voidp)0);
+#endif /* PNG_USER_MEM_SUPPORTED */
 
 #ifdef PNG_MAX_MALLOC_64K
    if (size > (png_uint_32)65536L)
@@ -275,7 +410,7 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
    ret = halloc(size, 1);
 # else
-   ret = malloc(size);
+   ret = malloc((size_t)size);
 # endif
 #endif
 
@@ -284,102 +419,94 @@ png_large_malloc(png_structp png_ptr, png_uint_32 size)
       png_error(png_ptr, "Out of Memory");
    }
 
-   return ret;
+   return (ret);
 }
 
-/* free a pointer allocated by png_large_malloc().  In the default
-  configuration, png_ptr is not used, but is passed in case it
-  is needed.  If ptr is NULL, return without taking any action. */
+/* Free a pointer allocated by png_malloc().  If ptr is NULL, return
+   without taking any action. */
 void
-png_large_free(png_structp png_ptr, png_voidp ptr)
+png_free(png_structp png_ptr, png_voidp ptr)
 {
-   if (!png_ptr)
+   if (png_ptr == NULL || ptr == NULL)
       return;
 
-   if (ptr != NULL)
+#ifdef PNG_USER_MEM_SUPPORTED
+   if (png_ptr->free_fn != NULL)
    {
+      (*(png_ptr->free_fn))(png_ptr, ptr);
+      ptr = NULL;
+      return;
+   }
+   else png_free_default(png_ptr, ptr);
+}
+void
+png_free_default(png_structp png_ptr, png_voidp ptr)
+{
+#endif /* PNG_USER_MEM_SUPPORTED */
+
 #if defined(__TURBOC__) && !defined(__FLAT__)
-      farfree(ptr);
+   farfree(ptr);
+   ptr = NULL;
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
-      hfree(ptr);
+   hfree(ptr);
+   ptr = NULL;
 # else
-      free(ptr);
+   free(ptr);
+   ptr = NULL;
 # endif
 #endif
-   }
 }
 
 #endif /* Not Borland DOS special memory handler */
 
-/* Allocate memory.  This is called for smallish blocks only  It
-   should not get anywhere near 64K.  On segmented machines, this
-   must come from the local heap (for zlib).  Currently, zlib is
-   the only one that uses this, so you should only get one call
-   to this, and that a small block. */
-void *
-png_malloc(png_structp png_ptr, png_uint_32 size)
+png_voidp
+png_memcpy_check (png_structp png_ptr, png_voidp s1, png_voidp s2,
+   png_uint_32 length)
 {
-   void *ret;
+   png_size_t size;
 
-   if (!png_ptr || !size)
-   {
-      return ((void *)0);
-   }
+   size = (png_size_t)length;
+   if ((png_uint_32)size != length)
+      png_error(png_ptr,"Overflow in png_memcpy_check.");
 
-#ifdef PNG_MAX_MALLOC_64K
-   if (size > (png_uint_32)65536L)
-      png_error(png_ptr, "Cannot Allocate > 64K");
-#endif
-
-
-   ret = malloc((png_size_t)size);
-
-   if (!ret)
-   {
-      png_error(png_ptr, "Out of Memory");
-   }
-
-   return ret;
+   return(png_memcpy (s1, s2, size));
 }
 
-/* Reallocate memory.  This will not get near 64K on a
-   even marginally reasonable file.  This is not used in
-   the current version of the library. */
-void *
-png_realloc(png_structp png_ptr, void * ptr, png_uint_32 size,
-   png_uint_32 old_size)
+png_voidp
+png_memset_check (png_structp png_ptr, png_voidp s1, int value,
+   png_uint_32 length)
 {
-   void *ret;
+   png_size_t size;
 
-   if (!png_ptr || !old_size || !ptr || !size)
-      return ((void *)0);
+   size = (png_size_t)length;
+   if ((png_uint_32)size != length)
+      png_error(png_ptr,"Overflow in png_memset_check.");
 
-#ifdef PNG_MAX_MALLOC_64K
-   if (size > (png_uint_32)65536L)
-      png_error(png_ptr, "Cannot Allocate > 64K");
-#endif
+   return (png_memset (s1, value, size));
 
-   ret = realloc(ptr, (png_size_t)size);
-
-   if (!ret)
-   {
-      png_error(png_ptr, "Out of Memory 7");
-   }
-
-   return ret;
 }
 
-/* free a pointer allocated by png_malloc().  In the default
-  configuration, png_ptr is not used, but is passed incase it
-  is needed.  If ptr is NULL, return without taking any action. */
+#ifdef PNG_USER_MEM_SUPPORTED
+/* This function is called when the application wants to use another method
+ * of allocating and freeing memory.
+ */
 void
-png_free(png_structp png_ptr, void * ptr)
+png_set_mem_fn(png_structp png_ptr, png_voidp mem_ptr, png_malloc_ptr
+  malloc_fn, png_free_ptr free_fn)
 {
-   if (!png_ptr)
-      return;
-
-   if (ptr != (void *)0)
-      free(ptr);
+   png_ptr->mem_ptr = mem_ptr;
+   png_ptr->malloc_fn = malloc_fn;
+   png_ptr->free_fn = free_fn;
 }
 
+/* This function returns a pointer to the mem_ptr associated with the user
+ * functions.  The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
+png_voidp
+png_get_mem_ptr(png_structp png_ptr)
+{
+   return ((png_voidp)png_ptr->mem_ptr);
+}
+#endif /* PNG_USER_MEM_SUPPORTED */

pngrcb.c

@@ -1,243 +0,0 @@
-/* pngrcb.c - callbacks while reading a png file
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-   */
-
-#define PNG_INTERNAL
-#include "png.h"
-
-void
-png_read_IHDR(png_structp png_ptr, png_infop info,
-   png_uint_32 width, png_uint_32 height, int bit_depth,
-   int color_type, int compression_type, int filter_type,
-   int interlace_type)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->width = width;
-   info->height = height;
-   info->bit_depth = (png_byte)bit_depth;
-   info->color_type =(png_byte) color_type;
-   info->compression_type = (png_byte)compression_type;
-   info->filter_type = (png_byte)filter_type;
-   info->interlace_type = (png_byte)interlace_type;
-   if (info->color_type == PNG_COLOR_TYPE_PALETTE)
-      info->channels = 1;
-   else if (info->color_type & PNG_COLOR_MASK_COLOR)
-      info->channels = 3;
-   else
-      info->channels = 1;
-   if (info->color_type & PNG_COLOR_MASK_ALPHA)
-      info->channels++;
-   info->pixel_depth = (png_byte)(info->channels * info->bit_depth);
-   info->rowbytes = ((info->width * info->pixel_depth + 7) >> 3);
-}
-
-void
-png_read_PLTE(png_structp png_ptr, png_infop info,
-   png_colorp palette, int num)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->palette = palette;
-   info->num_palette = (png_uint_16)num;
-   info->valid |= PNG_INFO_PLTE;
-}
-
-#if defined(PNG_READ_gAMA_SUPPORTED)
-void
-png_read_gAMA(png_structp png_ptr, png_infop info, double gamma)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->gamma = gamma;
-   info->valid |= PNG_INFO_gAMA;
-}
-#endif
-
-#if defined(PNG_READ_sBIT_SUPPORTED)
-void
-png_read_sBIT(png_structp png_ptr, png_infop info,
-   png_color_8p sig_bit)
-{
-   if (!png_ptr || !info)
-      return;
-
-   png_memcpy(&(info->sig_bit), sig_bit, sizeof (png_color_8));
-   info->valid |= PNG_INFO_sBIT;
-}
-#endif
-
-#if defined(PNG_READ_cHRM_SUPPORTED)
-void
-png_read_cHRM(png_structp png_ptr, png_infop info,
-   double white_x, double white_y, double red_x, double red_y,
-   double green_x, double green_y, double blue_x, double blue_y)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->x_white = white_x;
-   info->y_white = white_y;
-   info->x_red = red_x;
-   info->y_red = red_y;
-   info->x_green = green_x;
-   info->y_green = green_y;
-   info->x_blue = blue_x;
-   info->y_blue = blue_y;
-   info->valid |= PNG_INFO_cHRM;
-}
-#endif
-
-#if defined(PNG_READ_tRNS_SUPPORTED)
-void
-png_read_tRNS(png_structp png_ptr, png_infop info,
-   png_bytep trans, int num_trans,   png_color_16p trans_values)
-{
-   if (!png_ptr || !info)
-      return;
-
-   if (trans)
-   {
-      info->trans = trans;
-   }
-   else
-   {
-      png_memcpy(&(info->trans_values), trans_values,
-         sizeof(png_color_16));
-   }
-   info->num_trans = (png_uint_16)num_trans;
-   info->valid |= PNG_INFO_tRNS;
-}
-#endif
-
-#if defined(PNG_READ_bKGD_SUPPORTED)
-void
-png_read_bKGD(png_structp png_ptr, png_infop info,
-   png_color_16p background)
-{
-   if (!png_ptr || !info)
-      return;
-
-   png_memcpy(&(info->background), background, sizeof(png_color_16));
-   info->valid |= PNG_INFO_bKGD;
-}
-#endif
-
-#if defined(PNG_READ_hIST_SUPPORTED)
-void
-png_read_hIST(png_structp png_ptr, png_infop info, png_uint_16p hist)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->hist = hist;
-   info->valid |= PNG_INFO_hIST;
-}
-#endif
-
-#if defined(PNG_READ_pHYs_SUPPORTED)
-void
-png_read_pHYs(png_structp png_ptr, png_infop info,
-   png_uint_32 res_x, png_uint_32 res_y, int unit_type)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->x_pixels_per_unit = res_x;
-   info->y_pixels_per_unit = res_y;
-   info->phys_unit_type = (png_byte)unit_type;
-   info->valid |= PNG_INFO_pHYs;
-}
-#endif
-
-#if defined(PNG_READ_oFFs_SUPPORTED)
-void
-png_read_oFFs(png_structp png_ptr, png_infop info,
-   png_uint_32 offset_x, png_uint_32 offset_y, int unit_type)
-{
-   if (!png_ptr || !info)
-      return;
-
-   info->x_offset = offset_x;
-   info->y_offset = offset_y;
-   info->offset_unit_type = (png_byte)unit_type;
-   info->valid |= PNG_INFO_oFFs;
-}
-#endif
-
-#if defined(PNG_READ_tIME_SUPPORTED)
-void
-png_read_tIME(png_structp png_ptr, png_infop info,
-   png_timep mod_time)
-{
-   if (!png_ptr || !info)
-      return;
-
-   png_memcpy(&(info->mod_time), mod_time, sizeof (png_time));
-   info->valid |= PNG_INFO_tIME;
-}
-#endif
-
-#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_READ_zTXt_SUPPORTED)
-void
-png_read_zTXt(png_structp png_ptr, png_infop info,
-   png_charp key, png_charp text, png_uint_32 text_len, int compression)
-{
-   if (!png_ptr || !info)
-      return;
-
-   if (info->max_text <= info->num_text)
-   {
-      if (info->text)
-      {
-         png_uint_32 old_max;
-
-         old_max = info->max_text;
-         info->max_text = info->num_text + 16;
-         {
-            png_textp old_text;
-
-            old_text = info->text;
-            info->text = (png_textp)png_large_malloc(png_ptr,
-               info->max_text * sizeof (png_text));
-            png_memcpy(info->text, old_text,
-               (png_size_t)(old_max * sizeof (png_text)));
-            png_large_free(png_ptr, old_text);
-         }
-      }
-      else
-      {
-         info->max_text = 16;
-         info->num_text = 0;
-         info->text = (png_textp)png_large_malloc(png_ptr,
-            info->max_text * sizeof (png_text));
-      }
-   }
-
-   info->text[info->num_text].key = key;
-   info->text[info->num_text].text = text;
-   info->text[info->num_text].text_length = text_len;
-   info->text[info->num_text].compression = compression;
-   info->num_text++;
-}
-#endif
-
-#if defined(PNG_READ_tEXt_SUPPORTED)
-void
-png_read_tEXt(png_structp png_ptr, png_infop info,
-   png_charp key, png_charp text, png_uint_32 text_len)
-{
-   if (!png_ptr || !info)
-      return;
-
-   png_read_zTXt(png_ptr, info, key, text, text_len, -1);
-}
-#endif
-

pngrio.c

@@ -1,17 +1,19 @@
 
 /* pngrio.c - functions for data input
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-
-   This file provides a location for all input.  Users which need
-   special handling are expected to write a function which has the same
-   arguments as this, and perform a similar function, but possibly has
-   a different input method.  Note that you shouldn't change this
-   function, but rather write a replacement function and then make
-   libpng use it at run time with png_set_read_fn(...) */
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ *
+ * This file provides a location for all input.  Users who need
+ * special handling are expected to write a function that has the same
+ * arguments as this and performs a similar function, but that possibly
+ * has a different input method.  Note that you shouldn't change this
+ * function, but rather write a replacement function and then make
+ * libpng use it at run time with png_set_read_fn(...).
+ */
 
 #define PNG_INTERNAL
 #include "png.h"
@@ -20,28 +22,34 @@
    reads from a file pointer.  Note that this routine sometimes gets called
    with very small lengths, so you should implement some kind of simple
    buffering if you are using unbuffered reads.  This should never be asked
-   to read more then 64K on a 16 bit machine.  The cast to png_size_t is
-   there to quiet some compilers */
+   to read more then 64K on a 16 bit machine. */
 void
-png_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
+png_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
-   if (png_ptr->read_data_fn)
+   png_debug1(4,"reading %d bytes\n", length);
+   if (png_ptr->read_data_fn != NULL)
       (*(png_ptr->read_data_fn))(png_ptr, data, length);
    else
       png_error(png_ptr, "Call to NULL read function");
 }
 
-/* This is the function which does the actual reading of data.  If you are
+#if !defined(PNG_NO_STDIO)
+/* This is the function that does the actual reading of data.  If you are
    not reading from a standard C stream, you should create a replacement
    read_data function and use it at run time with png_set_read_fn(), rather
    than changing the library. */
 #ifndef USE_FAR_KEYWORD
 static void
-png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
-   png_uint_32 check;
+   png_size_t check;
+
+   /* fread() returns 0 on error, so it is OK to store this in a png_size_t
+    * instead of an int, which is what fread() actually returns.
+    */
+   check = (png_size_t)fread(data, (png_size_t)1, length,
+      (FILE *)png_ptr->io_ptr);
 
-   check = fread(data, 1, (size_t)length, (FILE *)png_ptr->io_ptr);
    if (check != length)
    {
       png_error(png_ptr, "Read Error");
@@ -52,44 +60,34 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
    can't handle far buffers in the medium and small models, we have to copy
    the data.
 */
- 
+
 #define NEAR_BUF_SIZE 1024
 #define MIN(a,b) (a <= b ? a : b)
- 
-#ifdef _MSC_VER
-/* for FP_OFF */
-#include <dos.h>
-#endif
- 
+
 static void
-png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
+png_default_read_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
-   png_uint_32 check;
+   int check;
    png_byte *n_data;
+   FILE *io_ptr;
 
    /* Check if data really is near. If so, use usual code. */
-#ifdef _MSC_VER
-   /* do it this way just to quiet warning */
-   FP_OFF(n_data) = FP_OFF(data);
-   if (FP_SEG(n_data) == FP_SEG(data))
-#else
-   /* this works in MSC also but with lost segment warning */
-   n_data = (png_byte *)data;
+   n_data = (png_byte *)CVT_PTR_NOCHECK(data);
+   io_ptr = (FILE *)CVT_PTR(png_ptr->io_ptr);
    if ((png_bytep)n_data == data)
-#endif
    {
-      check = fread(n_data, 1, (size_t)length, (FILE *)png_ptr->io_ptr);
+      check = fread(n_data, 1, length, io_ptr);
    }
    else
    {
       png_byte buf[NEAR_BUF_SIZE];
       png_size_t read, remaining, err;
       check = 0;
-      remaining = (png_size_t)length;
+      remaining = length;
       do
       {
          read = MIN(NEAR_BUF_SIZE, remaining);
-         err = fread(buf, 1, read, (FILE *)png_ptr->io_ptr);
+         err = fread(buf, (png_size_t)1, read, io_ptr);
          png_memcpy(data, buf, read); /* copy far buffer to near buffer */
          if(err != read)
             break;
@@ -100,12 +98,13 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
       }
       while (remaining != 0);
    }
-   if (check != length)
+   if ((png_uint_32)check != (png_uint_32)length)
    {
       png_error(png_ptr, "read Error");
    }
 }
 #endif
+#endif
 
 /* This function allows the application to supply a new input function
    for libpng if standard C streams aren't being used.
@@ -114,10 +113,10 @@ png_default_read_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
    png_ptr      - pointer to a png input data structure
    io_ptr       - pointer to user supplied structure containing info about
                   the input functions.  May be NULL.
-   read_data_fn - pointer to a new input function which takes as it's
+   read_data_fn - pointer to a new input function that takes as its
                   arguments a pointer to a png_struct, a pointer to
                   a location where input data can be stored, and a 32-bit
-                  unsigned int which is the number of bytes to be read.
+                  unsigned int that is the number of bytes to be read.
                   To exit and output any fatal error messages the new write
                   function should call png_error(png_ptr, "Error msg"). */
 void
@@ -126,13 +125,24 @@ png_set_read_fn(png_structp png_ptr, png_voidp io_ptr,
 {
    png_ptr->io_ptr = io_ptr;
 
-   if (read_data_fn)
+#if !defined(PNG_NO_STDIO)
+   if (read_data_fn != NULL)
       png_ptr->read_data_fn = read_data_fn;
    else
       png_ptr->read_data_fn = png_default_read_data;
+#else
+   png_ptr->read_data_fn = read_data_fn;
+#endif
 
    /* It is an error to write to a read device */
-   png_ptr->write_data_fn = NULL;
+   if (png_ptr->write_data_fn != NULL)
+   {
+      png_ptr->write_data_fn = NULL;
+      png_warning(png_ptr,
+         "It's an error to set both read_data_fn and write_data_fn in the ");
+      png_warning(png_ptr,
+         "same structure.  Resetting write_data_fn to NULL.");
+   }
 
 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
    png_ptr->output_flush_fn = NULL;

pngset.c

@@ -0,0 +1,391 @@
+
+/* pngset.c - storage of image information into info struct
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ *
+ * The functions here are used during reads to store data from the file
+ * into the info struct, and during writes to store application data
+ * into the info struct for writing into the file.  This abstracts the
+ * info struct and allows us to change the structure in the future.
+ */
+
+#define PNG_INTERNAL
+#include "png.h"
+
+#if defined(PNG_READ_bKGD_SUPPORTED) || defined(PNG_WRITE_bKGD_SUPPORTED)
+void
+png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
+{
+   png_debug1(1, "in %s storage function\n", "bKGD");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_memcpy(&(info_ptr->background), background, sizeof(png_color_16));
+   info_ptr->valid |= PNG_INFO_bKGD;
+}
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
+void
+png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
+   double white_x, double white_y, double red_x, double red_y,
+   double green_x, double green_y, double blue_x, double blue_y)
+{
+   png_debug1(1, "in %s storage function\n", "cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_white = (float)white_x;
+   info_ptr->y_white = (float)white_y;
+   info_ptr->x_red   = (float)red_x;
+   info_ptr->y_red   = (float)red_y;
+   info_ptr->x_green = (float)green_x;
+   info_ptr->y_green = (float)green_y;
+   info_ptr->x_blue  = (float)blue_x;
+   info_ptr->y_blue  = (float)blue_y;
+   info_ptr->valid |= PNG_INFO_cHRM;
+}
+#endif
+
+#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
+void
+png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
+{
+   png_debug1(1, "in %s storage function\n", "gAMA");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->gamma = (float)file_gamma;
+   info_ptr->valid |= PNG_INFO_gAMA;
+}
+#endif
+
+#if defined(PNG_READ_hIST_SUPPORTED) || defined(PNG_WRITE_hIST_SUPPORTED)
+void
+png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
+{
+   png_debug1(1, "in %s storage function\n", "hIST");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->hist = hist;
+   info_ptr->valid |= PNG_INFO_hIST;
+}
+#endif
+
+void
+png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 width, png_uint_32 height, int bit_depth,
+   int color_type, int interlace_type, int compression_type,
+   int filter_type)
+{
+   int rowbytes_per_pixel;
+   png_debug1(1, "in %s storage function\n", "IHDR");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->width = width;
+   info_ptr->height = height;
+   info_ptr->bit_depth = (png_byte)bit_depth;
+   info_ptr->color_type =(png_byte) color_type;
+   info_ptr->compression_type = (png_byte)compression_type;
+   info_ptr->filter_type = (png_byte)filter_type;
+   info_ptr->interlace_type = (png_byte)interlace_type;
+   if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+      info_ptr->channels = 1;
+   else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
+      info_ptr->channels = 3;
+   else
+      info_ptr->channels = 1;
+   if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
+      info_ptr->channels++;
+   info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
+
+   /* check for overflow */
+   rowbytes_per_pixel = (info_ptr->pixel_depth + 7) >> 3;
+   if (( width > PNG_MAX_UINT/rowbytes_per_pixel))
+   {
+      png_warning(png_ptr,
+         "Width too large to process image data; rowbytes will overflow.");
+      info_ptr->rowbytes = (png_size_t)0;
+   }
+   else
+      info_ptr->rowbytes = (info_ptr->width * info_ptr->pixel_depth + 7) >> 3;
+}
+
+#if defined(PNG_READ_oFFs_SUPPORTED) || defined(PNG_WRITE_oFFs_SUPPORTED)
+void
+png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 offset_x, png_uint_32 offset_y, int unit_type)
+{
+   png_debug1(1, "in %s storage function\n", "oFFs");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_offset = offset_x;
+   info_ptr->y_offset = offset_y;
+   info_ptr->offset_unit_type = (png_byte)unit_type;
+   info_ptr->valid |= PNG_INFO_oFFs;
+}
+#endif
+
+#if defined(PNG_READ_pCAL_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED)
+void
+png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
+   png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
+   png_charp units, png_charpp params)
+{
+   png_uint_32 length;
+   int i;
+
+   png_debug1(1, "in %s storage function\n", "pCAL");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   length = png_strlen(purpose) + 1;
+   png_debug1(3, "allocating purpose for info (%d bytes)\n", length);
+   info_ptr->pcal_purpose = (png_charp)png_malloc(png_ptr, length);
+   png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
+
+   png_debug(3, "storing X0, X1, type, and nparams in info\n");
+   info_ptr->pcal_X0 = X0;
+   info_ptr->pcal_X1 = X1;
+   info_ptr->pcal_type = (png_byte)type;
+   info_ptr->pcal_nparams = (png_byte)nparams;
+
+   length = png_strlen(units) + 1;
+   png_debug1(3, "allocating units for info (%d bytes)\n", length);
+   info_ptr->pcal_units = (png_charp)png_malloc(png_ptr, length);
+   png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
+
+   info_ptr->pcal_params = (png_charpp)png_malloc(png_ptr,
+      (png_uint_32)((nparams + 1) * sizeof(png_charp)));
+   info_ptr->pcal_params[nparams] = NULL;
+
+   for (i = 0; i < nparams; i++)
+   {
+      length = png_strlen(params[i]) + 1;
+      png_debug2(3, "allocating parameter %d for info (%d bytes)\n", i, length);
+      info_ptr->pcal_params[i] = (png_charp)png_malloc(png_ptr, length);
+      png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
+   }
+
+   info_ptr->valid |= PNG_INFO_pCAL;
+}
+#endif
+
+#if defined(PNG_READ_pHYs_SUPPORTED) || defined(PNG_WRITE_pHYs_SUPPORTED)
+void
+png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
+   png_uint_32 res_x, png_uint_32 res_y, int unit_type)
+{
+   png_debug1(1, "in %s storage function\n", "pHYs");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->x_pixels_per_unit = res_x;
+   info_ptr->y_pixels_per_unit = res_y;
+   info_ptr->phys_unit_type = (png_byte)unit_type;
+   info_ptr->valid |= PNG_INFO_pHYs;
+}
+#endif
+
+void
+png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
+   png_colorp palette, int num_palette)
+{
+   png_debug1(1, "in %s storage function\n", "PLTE");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->palette = palette;
+   info_ptr->num_palette = (png_uint_16)num_palette;
+   info_ptr->valid |= PNG_INFO_PLTE;
+}
+
+#if defined(PNG_READ_sBIT_SUPPORTED) || defined(PNG_WRITE_sBIT_SUPPORTED)
+void
+png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
+   png_color_8p sig_bit)
+{
+   png_debug1(1, "in %s storage function\n", "sBIT");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_memcpy(&(info_ptr->sig_bit), sig_bit, sizeof (png_color_8));
+   info_ptr->valid |= PNG_INFO_sBIT;
+}
+#endif
+
+#if defined(PNG_READ_sRGB_SUPPORTED) || defined(PNG_WRITE_sRGB_SUPPORTED)
+void
+png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
+{
+   png_debug1(1, "in %s storage function\n", "sRGB");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   info_ptr->srgb_intent = (png_byte)intent;
+   info_ptr->valid |= PNG_INFO_sRGB;
+}
+void
+png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
+   int intent)
+{
+#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
+   float file_gamma;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
+   float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
+#endif
+   png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   png_set_sRGB(png_ptr, info_ptr, intent);
+
+#if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
+   file_gamma = (float).45;
+   png_set_gAMA(png_ptr, info_ptr, file_gamma);
+#endif
+
+#if defined(PNG_READ_cHRM_SUPPORTED) || defined(PNG_WRITE_cHRM_SUPPORTED)
+   white_x = (float).3127;
+   white_y = (float).3290;
+   red_x   = (float).64;
+   red_y   = (float).33;
+   green_x = (float).30;
+   green_y = (float).60;
+   blue_x  = (float).15;
+   blue_y  = (float).06;
+
+   png_set_cHRM(png_ptr, info_ptr,
+      white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
+
+#endif
+}
+#endif
+
+#if defined(PNG_READ_tEXt_SUPPORTED) || defined(PNG_WRITE_tEXt_SUPPORTED) || \
+    defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
+void
+png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
+   int num_text)
+{
+   int i;
+
+   png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
+      "text" : (png_const_charp)png_ptr->chunk_name));
+
+   if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
+      return;
+
+   /* Make sure we have enough space in the "text" array in info_struct
+    * to hold all of the incoming text_ptr objects.
+    */
+   if (info_ptr->num_text + num_text > info_ptr->max_text)
+   {
+      if (info_ptr->text != NULL)
+      {
+         png_textp old_text;
+         int old_max;
+
+         old_max = info_ptr->max_text;
+         info_ptr->max_text = info_ptr->num_text + num_text + 8;
+         old_text = info_ptr->text;
+         info_ptr->text = (png_textp)png_malloc(png_ptr,
+            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
+         png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
+            sizeof(png_text)));
+         png_free(png_ptr, old_text);
+      }
+      else
+      {
+         info_ptr->max_text = num_text + 8;
+         info_ptr->num_text = 0;
+         info_ptr->text = (png_textp)png_malloc(png_ptr,
+            (png_uint_32)(info_ptr->max_text * sizeof (png_text)));
+      }
+      png_debug1(3, "allocated %d entries for info_ptr->text\n",
+         info_ptr->max_text);
+   }
+
+   for (i = 0; i < num_text; i++)
+   {
+      png_textp textp = &(info_ptr->text[info_ptr->num_text]);
+
+      if (text_ptr[i].text == NULL)
+         text_ptr[i].text = (png_charp)"";
+
+      if (text_ptr[i].text[0] == '\0')
+      {
+         textp->text_length = 0;
+         textp->compression = PNG_TEXT_COMPRESSION_NONE;
+      }
+      else
+      {
+         textp->text_length = png_strlen(text_ptr[i].text);
+         textp->compression = text_ptr[i].compression;
+      }
+      textp->text = text_ptr[i].text;
+      textp->key = text_ptr[i].key;
+      info_ptr->num_text++;
+      png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
+   }
+}
+#endif
+
+#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
+void
+png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
+{
+   png_debug1(1, "in %s storage function\n", "tIME");
+   if (png_ptr == NULL || info_ptr == NULL ||
+       (png_ptr->flags & PNG_FLAG_WROTE_tIME))
+      return;
+
+   png_memcpy(&(info_ptr->mod_time), mod_time, sizeof (png_time));
+   info_ptr->valid |= PNG_INFO_tIME;
+}
+#endif
+
+#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED)
+void
+png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
+   png_bytep trans, int num_trans, png_color_16p trans_values)
+{
+   png_debug1(1, "in %s storage function\n", "tRNS");
+   if (png_ptr == NULL || info_ptr == NULL)
+      return;
+
+   if (trans != NULL)
+   {
+      info_ptr->trans = trans;
+   }
+
+   if (trans_values != NULL)
+   {
+      png_memcpy(&(info_ptr->trans_values), trans_values,
+         sizeof(png_color_16));
+      if (num_trans == 0)
+        num_trans = 1;
+   }
+   info_ptr->num_trans = (png_uint_16)num_trans;
+   info_ptr->valid |= PNG_INFO_tRNS;
+}
+#endif
+
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED)
+void
+png_permit_empty_plte (png_structp png_ptr, int empty_plte_permitted)
+{
+   png_debug1(1, "in png_permit_empty_plte\n", "");
+   if (png_ptr == NULL)
+      return;
+   png_ptr->empty_plte_permitted=(png_byte)empty_plte_permitted;
+}
+#endif

pngtodo.txt

@@ -1,27 +0,0 @@
-pngtodo.txt - list of things to do for libpng
-
-for 0.9
-   improved dithering
-   final bug fixes
-   cHRM transformation
-   better documentation
-
-after 1.0
-   overlaying one image on top of another
-   make pull reader use push reader internally to reduce code, and
-      increase amount of image read in an error situation
-   optional palette creation
-   histogram creation
-   text conversion between different code types
-   support for other chunks being defined (sCAl, the gIF series,
-      and others that people come up with).
-   pull writer
-   better dithering
-   keep up with public chunks
-   other compression libraries
-   more exotic interlace handling
-   better filtering (counting huffman bits?  filter type inertia?)
-   C++ wrapper
-   other languages (pascal, for one)
-   comments of > 64K
-

pngtrans.c

@@ -1,21 +1,22 @@
 
-/* pngtrans.c - transforms the data in a row
-   routines used by both readers and writers
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-   */
+/* pngtrans.c - transforms the data in a row (used by both readers and writers)
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ */
 
 #define PNG_INTERNAL
 #include "png.h"
 
 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* turn on bgr to rgb mapping */
+/* turn on BGR-to-RGB mapping */
 void
 png_set_bgr(png_structp png_ptr)
 {
+   png_debug(1, "in png_set_bgr\n");
    png_ptr->transformations |= PNG_BGR;
 }
 #endif
@@ -25,6 +26,7 @@ png_set_bgr(png_structp png_ptr)
 void
 png_set_swap(png_structp png_ptr)
 {
+   png_debug(1, "in png_set_swap\n");
    if (png_ptr->bit_depth == 16)
       png_ptr->transformations |= PNG_SWAP_BYTES;
 }
@@ -35,6 +37,7 @@ png_set_swap(png_structp png_ptr)
 void
 png_set_packing(png_structp png_ptr)
 {
+   png_debug(1, "in png_set_packing\n");
    if (png_ptr->bit_depth < 8)
    {
       png_ptr->transformations |= PNG_PACK;
@@ -43,33 +46,53 @@ png_set_packing(png_structp png_ptr)
 }
 #endif
 
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+/* turn on packed pixel swapping */
+void
+png_set_packswap(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_packswap\n");
+   if (png_ptr->bit_depth < 8)
+      png_ptr->transformations |= PNG_PACKSWAP;
+}
+#endif
+
 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
 void
 png_set_shift(png_structp png_ptr, png_color_8p true_bits)
 {
+   png_debug(1, "in png_set_shift\n");
    png_ptr->transformations |= PNG_SHIFT;
    png_ptr->shift = *true_bits;
 }
 #endif
 
-#if defined(PNG_READ_INTERLACING_SUPPORTED) || defined(PNG_WRITE_INTERLACING_SUPPORTED)
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+    defined(PNG_WRITE_INTERLACING_SUPPORTED)
 int
 png_set_interlace_handling(png_structp png_ptr)
 {
+   png_debug(1, "in png_set_interlace handling\n");
    if (png_ptr->interlaced)
    {
       png_ptr->transformations |= PNG_INTERLACE;
-      return 7;
+      return (7);
    }
 
-   return 1;
+   return (1);
 }
 #endif
 
 #if defined(PNG_READ_FILLER_SUPPORTED) || defined(PNG_WRITE_FILLER_SUPPORTED)
+/* Add a filler byte on read, or remove a filler or alpha byte on write.
+ * The filler type has changed in v0.95 to allow future 2-byte fillers
+ * for 48-bit input data, as well as to avoid problems with some compilers
+ * that don't like bytes as parameters.
+ */
 void
-png_set_filler(png_structp png_ptr, int filler, int filler_loc)
+png_set_filler(png_structp png_ptr, png_uint_32 filler, int filler_loc)
 {
+   png_debug(1, "in png_set_filler\n");
    png_ptr->transformations |= PNG_FILLER;
    png_ptr->filler = (png_byte)filler;
    if (filler_loc == PNG_FILLER_AFTER)
@@ -77,22 +100,43 @@ png_set_filler(png_structp png_ptr, int filler, int filler_loc)
    else
       png_ptr->flags &= ~PNG_FLAG_FILLER_AFTER;
 
-   if (png_ptr->color_type == PNG_COLOR_TYPE_RGB &&
-      png_ptr->bit_depth == 8)
+   /* This should probably go in the "do_filler" routine.
+    * I attempted to do that in libpng-1.0.1a but that caused problems
+    * so I restored it in libpng-1.0.2a
+   */
+
+   if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
+   {
       png_ptr->usr_channels = 4;
-}
+   }
 
-/* old functions kept around for compatability purposes */
-void
-png_set_rgbx(png_structp png_ptr)
-{
-   png_set_filler(png_ptr, 0xff, PNG_FILLER_AFTER);
-}
+   /* Also I added this in libpng-1.0.2a (what happens when we expand
+    * a less-than-8-bit grayscale to GA? */
 
+   if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY && png_ptr->bit_depth >= 8)
+   {
+      png_ptr->usr_channels = 2;
+   }
+}
+#endif
+
+#if defined(PNG_READ_SWAP_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
 void
-png_set_xrgb(png_structp png_ptr)
+png_set_swap_alpha(png_structp png_ptr)
 {
-   png_set_filler(png_ptr, 0xff, PNG_FILLER_BEFORE);
+   png_debug(1, "in png_set_swap_alpha\n");
+   png_ptr->transformations |= PNG_SWAP_ALPHA;
+}
+#endif
+
+#if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) || \
+    defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+void
+png_set_invert_alpha(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_invert_alpha\n");
+   png_ptr->transformations |= PNG_INVERT_ALPHA;
 }
 #endif
 
@@ -100,24 +144,29 @@ png_set_xrgb(png_structp png_ptr)
 void
 png_set_invert_mono(png_structp png_ptr)
 {
+   png_debug(1, "in png_set_invert_mono\n");
    png_ptr->transformations |= PNG_INVERT_MONO;
 }
 
-/* invert monocrome grayscale data */
+/* invert monochrome grayscale data */
 void
 png_do_invert(png_row_infop row_info, png_bytep row)
 {
-   if (row && row_info && row_info->bit_depth == 1 &&
-      row_info->color_type == PNG_COLOR_TYPE_GRAY)
+   png_debug(1, "in png_do_invert\n");
+   if (row_info->bit_depth == 1 &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       row_info->color_type == PNG_COLOR_TYPE_GRAY)
    {
-      png_bytep rp;
+      png_bytep rp = row;
       png_uint_32 i;
+      png_uint_32 istop = row_info->rowbytes;
 
-      for (i = 0, rp = row;
-         i < row_info->rowbytes;
-         i++, rp++)
+      for (i = 0; i < istop; i++)
       {
          *rp = (png_byte)(~(*rp));
+         rp++;
       }
    }
 }
@@ -128,17 +177,20 @@ png_do_invert(png_row_infop row_info, png_bytep row)
 void
 png_do_swap(png_row_infop row_info, png_bytep row)
 {
-   if (row && row_info && row_info->bit_depth == 16)
+   png_debug(1, "in png_do_swap\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       row_info->bit_depth == 16)
    {
-      png_bytep rp;
-      png_byte t;
+      png_bytep rp = row;
       png_uint_32 i;
+      png_uint_32 istop= row_info->width * row_info->channels;
 
-      for (i = 0, rp = row;
-         i < row_info->width * row_info->channels;
-         i++, rp += 2)
+      for (i = 0; i < istop; i++, rp += 2)
       {
-         t = *rp;
+         png_byte t = *rp;
          *rp = *(rp + 1);
          *(rp + 1) = t;
       }
@@ -146,80 +198,398 @@ png_do_swap(png_row_infop row_info, png_bytep row)
 }
 #endif
 
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-/* swaps red and blue */
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)||defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+static png_byte onebppswaptable[256] = {
+   0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0,
+   0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0,
+   0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8,
+   0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8,
+   0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4,
+   0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4,
+   0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC,
+   0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC,
+   0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2,
+   0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2,
+   0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA,
+   0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA,
+   0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
+   0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6,
+   0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE,
+   0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE,
+   0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1,
+   0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1,
+   0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9,
+   0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9,
+   0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5,
+   0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5,
+   0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED,
+   0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD,
+   0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3,
+   0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
+   0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB,
+   0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB,
+   0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7,
+   0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7,
+   0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF,
+   0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
+};
+
+static png_byte twobppswaptable[256] = {
+   0x00, 0x40, 0x80, 0xC0, 0x10, 0x50, 0x90, 0xD0,
+   0x20, 0x60, 0xA0, 0xE0, 0x30, 0x70, 0xB0, 0xF0,
+   0x04, 0x44, 0x84, 0xC4, 0x14, 0x54, 0x94, 0xD4,
+   0x24, 0x64, 0xA4, 0xE4, 0x34, 0x74, 0xB4, 0xF4,
+   0x08, 0x48, 0x88, 0xC8, 0x18, 0x58, 0x98, 0xD8,
+   0x28, 0x68, 0xA8, 0xE8, 0x38, 0x78, 0xB8, 0xF8,
+   0x0C, 0x4C, 0x8C, 0xCC, 0x1C, 0x5C, 0x9C, 0xDC,
+   0x2C, 0x6C, 0xAC, 0xEC, 0x3C, 0x7C, 0xBC, 0xFC,
+   0x01, 0x41, 0x81, 0xC1, 0x11, 0x51, 0x91, 0xD1,
+   0x21, 0x61, 0xA1, 0xE1, 0x31, 0x71, 0xB1, 0xF1,
+   0x05, 0x45, 0x85, 0xC5, 0x15, 0x55, 0x95, 0xD5,
+   0x25, 0x65, 0xA5, 0xE5, 0x35, 0x75, 0xB5, 0xF5,
+   0x09, 0x49, 0x89, 0xC9, 0x19, 0x59, 0x99, 0xD9,
+   0x29, 0x69, 0xA9, 0xE9, 0x39, 0x79, 0xB9, 0xF9,
+   0x0D, 0x4D, 0x8D, 0xCD, 0x1D, 0x5D, 0x9D, 0xDD,
+   0x2D, 0x6D, 0xAD, 0xED, 0x3D, 0x7D, 0xBD, 0xFD,
+   0x02, 0x42, 0x82, 0xC2, 0x12, 0x52, 0x92, 0xD2,
+   0x22, 0x62, 0xA2, 0xE2, 0x32, 0x72, 0xB2, 0xF2,
+   0x06, 0x46, 0x86, 0xC6, 0x16, 0x56, 0x96, 0xD6,
+   0x26, 0x66, 0xA6, 0xE6, 0x36, 0x76, 0xB6, 0xF6,
+   0x0A, 0x4A, 0x8A, 0xCA, 0x1A, 0x5A, 0x9A, 0xDA,
+   0x2A, 0x6A, 0xAA, 0xEA, 0x3A, 0x7A, 0xBA, 0xFA,
+   0x0E, 0x4E, 0x8E, 0xCE, 0x1E, 0x5E, 0x9E, 0xDE,
+   0x2E, 0x6E, 0xAE, 0xEE, 0x3E, 0x7E, 0xBE, 0xFE,
+   0x03, 0x43, 0x83, 0xC3, 0x13, 0x53, 0x93, 0xD3,
+   0x23, 0x63, 0xA3, 0xE3, 0x33, 0x73, 0xB3, 0xF3,
+   0x07, 0x47, 0x87, 0xC7, 0x17, 0x57, 0x97, 0xD7,
+   0x27, 0x67, 0xA7, 0xE7, 0x37, 0x77, 0xB7, 0xF7,
+   0x0B, 0x4B, 0x8B, 0xCB, 0x1B, 0x5B, 0x9B, 0xDB,
+   0x2B, 0x6B, 0xAB, 0xEB, 0x3B, 0x7B, 0xBB, 0xFB,
+   0x0F, 0x4F, 0x8F, 0xCF, 0x1F, 0x5F, 0x9F, 0xDF,
+   0x2F, 0x6F, 0xAF, 0xEF, 0x3F, 0x7F, 0xBF, 0xFF
+};
+
+static png_byte fourbppswaptable[256] = {
+   0x00, 0x10, 0x20, 0x30, 0x40, 0x50, 0x60, 0x70,
+   0x80, 0x90, 0xA0, 0xB0, 0xC0, 0xD0, 0xE0, 0xF0,
+   0x01, 0x11, 0x21, 0x31, 0x41, 0x51, 0x61, 0x71,
+   0x81, 0x91, 0xA1, 0xB1, 0xC1, 0xD1, 0xE1, 0xF1,
+   0x02, 0x12, 0x22, 0x32, 0x42, 0x52, 0x62, 0x72,
+   0x82, 0x92, 0xA2, 0xB2, 0xC2, 0xD2, 0xE2, 0xF2,
+   0x03, 0x13, 0x23, 0x33, 0x43, 0x53, 0x63, 0x73,
+   0x83, 0x93, 0xA3, 0xB3, 0xC3, 0xD3, 0xE3, 0xF3,
+   0x04, 0x14, 0x24, 0x34, 0x44, 0x54, 0x64, 0x74,
+   0x84, 0x94, 0xA4, 0xB4, 0xC4, 0xD4, 0xE4, 0xF4,
+   0x05, 0x15, 0x25, 0x35, 0x45, 0x55, 0x65, 0x75,
+   0x85, 0x95, 0xA5, 0xB5, 0xC5, 0xD5, 0xE5, 0xF5,
+   0x06, 0x16, 0x26, 0x36, 0x46, 0x56, 0x66, 0x76,
+   0x86, 0x96, 0xA6, 0xB6, 0xC6, 0xD6, 0xE6, 0xF6,
+   0x07, 0x17, 0x27, 0x37, 0x47, 0x57, 0x67, 0x77,
+   0x87, 0x97, 0xA7, 0xB7, 0xC7, 0xD7, 0xE7, 0xF7,
+   0x08, 0x18, 0x28, 0x38, 0x48, 0x58, 0x68, 0x78,
+   0x88, 0x98, 0xA8, 0xB8, 0xC8, 0xD8, 0xE8, 0xF8,
+   0x09, 0x19, 0x29, 0x39, 0x49, 0x59, 0x69, 0x79,
+   0x89, 0x99, 0xA9, 0xB9, 0xC9, 0xD9, 0xE9, 0xF9,
+   0x0A, 0x1A, 0x2A, 0x3A, 0x4A, 0x5A, 0x6A, 0x7A,
+   0x8A, 0x9A, 0xAA, 0xBA, 0xCA, 0xDA, 0xEA, 0xFA,
+   0x0B, 0x1B, 0x2B, 0x3B, 0x4B, 0x5B, 0x6B, 0x7B,
+   0x8B, 0x9B, 0xAB, 0xBB, 0xCB, 0xDB, 0xEB, 0xFB,
+   0x0C, 0x1C, 0x2C, 0x3C, 0x4C, 0x5C, 0x6C, 0x7C,
+   0x8C, 0x9C, 0xAC, 0xBC, 0xCC, 0xDC, 0xEC, 0xFC,
+   0x0D, 0x1D, 0x2D, 0x3D, 0x4D, 0x5D, 0x6D, 0x7D,
+   0x8D, 0x9D, 0xAD, 0xBD, 0xCD, 0xDD, 0xED, 0xFD,
+   0x0E, 0x1E, 0x2E, 0x3E, 0x4E, 0x5E, 0x6E, 0x7E,
+   0x8E, 0x9E, 0xAE, 0xBE, 0xCE, 0xDE, 0xEE, 0xFE,
+   0x0F, 0x1F, 0x2F, 0x3F, 0x4F, 0x5F, 0x6F, 0x7F,
+   0x8F, 0x9F, 0xAF, 0xBF, 0xCF, 0xDF, 0xEF, 0xFF
+};
+
+/* swaps pixel packing order within bytes */
 void
-png_do_bgr(png_row_infop row_info, png_bytep row)
+png_do_packswap(png_row_infop row_info, png_bytep row)
 {
-   if (row && row_info && (row_info->color_type & 2))
+   png_debug(1, "in png_do_packswap\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       row_info->bit_depth < 8)
    {
-      if (row_info->color_type == 2 && row_info->bit_depth == 8)
-      {
-         png_bytep rp;
-         png_byte t;
-         png_uint_32 i;
+      png_bytep rp, end, table;
 
-         for (i = 0, rp = row;
-            i < row_info->width;
-            i++, rp += 3)
+      end = row + row_info->rowbytes;
+
+      if (row_info->bit_depth == 1)
+         table = onebppswaptable;
+      else if (row_info->bit_depth == 2)
+         table = twobppswaptable;
+      else if (row_info->bit_depth == 4)
+         table = fourbppswaptable;
+      else
+         return;
+
+      for (rp = row; rp < end; rp++)
+         *rp = table[*rp];
+   }
+}
+#endif /* PNG_READ_PACKSWAP_SUPPORTED or PNG_WRITE_PACKSWAP_SUPPORTED */
+
+#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
+    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
+/* remove filler or alpha byte(s) */
+void
+png_do_strip_filler(png_row_infop row_info, png_bytep row, png_uint_32 flags)
+{
+   png_debug(1, "in png_do_strip_filler\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+/*
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB ||
+          row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+*/
+      png_bytep sp=row;
+      png_bytep dp=row;
+      png_uint_32 row_width=row_info->width;
+      png_uint_32 i;
+
+      if (row_info->channels == 4)
+      {
+         if (row_info->bit_depth == 8)
          {
-            t = *rp;
-            *rp = *(rp + 2);
-            *(rp + 2) = t;
+            /* This converts from RGBX or RGBA to RGB */
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               dp+=3; sp+=4;
+               for (i = 1; i < row_width; i++)
+               {
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  sp++;
+               }
+            }
+            /* This converts from XRGB or ARGB to RGB */
+            else
+            {
+               for (i = 0; i < row_width; i++)
+               {
+                  sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 24;
+            row_info->rowbytes = row_width * 3;
          }
+         else /* if (row_info->bit_depth == 16) */
+         {
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               /* This converts from RRGGBBXX or RRGGBBAA to RRGGBB */
+               sp += 8; dp += 6;
+               for (i = 1; i < row_width; i++)
+               {
+                  /* This could be (although memcpy is probably slower):
+                  png_memcpy(dp, sp, 6);
+                  sp += 8;
+                  dp += 6;
+                  */
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  sp += 2;
+               }
+            }
+            else
+            {
+               /* This converts from XXRRGGBB or AARRGGBB to RRGGBB */
+               for (i = 0; i < row_width; i++)
+               {
+                  /* This could be (although memcpy is probably slower):
+                  png_memcpy(dp, sp, 6);
+                  sp += 8;
+                  dp += 6;
+                  */
+                  sp+=2;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 48;
+            row_info->rowbytes = row_width * 6;
+         }
+         row_info->channels = 3;
+         row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
       }
-      else if (row_info->color_type == 6 && row_info->bit_depth == 8)
+/*
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY ||
+               row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+*/
+      else if (row_info->channels == 2)
       {
-         png_bytep rp;
-         png_byte t;
-         png_uint_32 i;
-
-         for (i = 0, rp = row;
-            i < row_info->width;
-            i++, rp += 4)
+         if (row_info->bit_depth == 8)
          {
-            t = *rp;
-            *rp = *(rp + 2);
-            *(rp + 2) = t;
+            /* This converts from GX or GA to G */
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               for (i = 0; i < row_width; i++)
+               {
+                  *dp++ = *sp++;
+                  sp++;
+               }
+            }
+            /* This converts from XG or AG to G */
+            else
+            {
+               for (i = 0; i < row_width; i++)
+               {
+                  sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 8;
+            row_info->rowbytes = row_width;
          }
-      }
-      else if (row_info->color_type == 2 && row_info->bit_depth == 16)
-      {
-         png_bytep rp;
-         png_byte t[2];
-         png_uint_32 i;
-
-         for (i = 0, rp = row;
-            i < row_info->width;
-            i++, rp += 6)
+         else /* if (row_info->bit_depth == 16) */
          {
-            t[0] = *rp;
-            t[1] = *(rp + 1);
-            *rp = *(rp + 4);
-            *(rp + 1) = *(rp + 5);
-            *(rp + 4) = t[0];
-            *(rp + 5) = t[1];
-         }
-      }
-      else if (row_info->color_type == 6 && row_info->bit_depth == 16)
-      {
-         png_bytep rp;
-         png_byte t[2];
-         png_uint_32 i;
-
-         for (i = 0, rp = row;
-            i < row_info->width;
-            i++, rp += 8)
-         {
-            t[0] = *rp;
-            t[1] = *(rp + 1);
-            *rp = *(rp + 4);
-            *(rp + 1) = *(rp + 5);
-            *(rp + 4) = t[0];
-            *(rp + 5) = t[1];
+            if (flags & PNG_FLAG_FILLER_AFTER)
+            {
+               /* This converts from GGXX or GGAA to GG */
+               sp += 4; dp += 2;
+               for (i = 1; i < row_width; i++)
+               {
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+                  sp += 2;
+               }
+            }
+            else
+            {
+               /* This converts from XXGG or AAGG to GG */
+               for (i = 0; i < row_width; i++)
+               {
+                  sp += 2;
+                  *dp++ = *sp++;
+                  *dp++ = *sp++;
+               }
+            }
+            row_info->pixel_depth = 16;
+            row_info->rowbytes = row_width * 2;
          }
+         row_info->channels = 1;
+         row_info->color_type &= ~PNG_COLOR_MASK_ALPHA;
       }
    }
 }
 #endif
 
+#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
+/* swaps red and blue bytes within a pixel */
+void
+png_do_bgr(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_bgr\n");
+   if (
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
+       (row_info->color_type & PNG_COLOR_MASK_COLOR))
+   {
+      png_uint_32 row_width = row_info->width;
+      if (row_info->bit_depth == 8)
+      {
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 3)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 2);
+               *(rp + 2) = save;
+            }
+         }
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 4)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 2);
+               *(rp + 2) = save;
+            }
+         }
+      }
+      else if (row_info->bit_depth == 16)
+      {
+         if (row_info->color_type == PNG_COLOR_TYPE_RGB)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 6)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 4);
+               *(rp + 4) = save;
+               save = *(rp + 1);
+               *(rp + 1) = *(rp + 5);
+               *(rp + 5) = save;
+            }
+         }
+         else if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+         {
+            png_bytep rp;
+            png_uint_32 i;
+
+            for (i = 0, rp = row; i < row_width; i++, rp += 8)
+            {
+               png_byte save = *rp;
+               *rp = *(rp + 4);
+               *(rp + 4) = save;
+               save = *(rp + 1);
+               *(rp + 1) = *(rp + 5);
+               *(rp + 5) = save;
+            }
+         }
+      }
+   }
+}
+#endif /* PNG_READ_BGR_SUPPORTED or PNG_WRITE_BGR_SUPPORTED */
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+void
+png_set_user_transform_info(png_structp png_ptr, png_voidp
+   user_transform_ptr, int user_transform_depth, int user_transform_channels)
+{
+   png_debug(1, "in png_set_user_transform_info\n");
+   png_ptr->user_transform_ptr = user_transform_ptr;
+   png_ptr->user_transform_depth = user_transform_depth;
+   png_ptr->user_transform_channels = user_transform_channels;
+}
+
+/* This function returns a pointer to the user_transform_ptr associated with
+ * the user transform functions.  The application should free any memory
+ * associated with this pointer before png_write_destroy and png_read_destroy
+ * are called.
+ */
+png_voidp
+png_get_user_transform_ptr(png_structp png_ptr)
+{
+   return ((png_voidp)png_ptr->user_transform_ptr);
+}
+#endif

pngwio.c

@@ -1,17 +1,19 @@
 
 /* pngwio.c - functions for data output
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-
-   This file provides a location for all output.  Users which need
-   special handling are expected to write functions which have the same
-   arguments as these, and perform similar functions, but possibly use
-   different output methods.  Note that you shouldn't change these
-   functions, but rather write replacement functions and then change
-   them at run time with png_set_write_fn(...) */
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ *
+ * This file provides a location for all output.  Users who need
+ * special handling are expected to write functions that have the same
+ * arguments as these and perform similar functions, but that possibly
+ * use different output methods.  Note that you shouldn't change these
+ * functions, but rather write replacement functions and then change
+ * them at run time with png_set_write_fn(...).
+ */
 
 #define PNG_INTERNAL
 #include "png.h"
@@ -20,29 +22,29 @@
    writes to a file pointer.  Note that this routine sometimes gets called
    with very small lengths, so you should implement some kind of simple
    buffering if you are using unbuffered writes.  This should never be asked
-   to write more then 64K on a 16 bit machine.  The cast to png_size_t is
-   there to quiet warnings of certain compilers. */
+   to write more than 64K on a 16 bit machine.  */
 
 void
-png_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
+png_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
-   if (png_ptr->write_data_fn)
+   if (png_ptr->write_data_fn != NULL )
       (*(png_ptr->write_data_fn))(png_ptr, data, length);
    else
       png_error(png_ptr, "Call to NULL write function");
 }
 
-/* This is the function which does the actual writing of data.  If you are
+#if !defined(PNG_NO_STDIO)
+/* This is the function that does the actual writing of data.  If you are
    not writing to a standard C stream, you should create a replacement
    write_data function and use it at run time with png_set_write_fn(), rather
    than changing the library. */
 #ifndef USE_FAR_KEYWORD
 static void
-png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
    png_uint_32 check;
 
-   check = fwrite(data, 1, (png_size_t)length, (FILE *)(png_ptr->io_ptr));
+   check = fwrite(data, 1, length, (FILE *)(png_ptr->io_ptr));
    if (check != length)
    {
       png_error(png_ptr, "Write Error");
@@ -57,41 +59,31 @@ png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
 #define NEAR_BUF_SIZE 1024
 #define MIN(a,b) (a <= b ? a : b)
 
-#ifdef _MSC_VER
-/* for FP_OFF */
-#include <dos.h>
-#endif
-
 static void
-png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
+png_default_write_data(png_structp png_ptr, png_bytep data, png_size_t length)
 {
    png_uint_32 check;
-   png_byte *n_data;
+   png_byte *near_data;  /* Needs to be "png_byte *" instead of "png_bytep" */
+   FILE *io_ptr;
 
    /* Check if data really is near. If so, use usual code. */
-#ifdef _MSC_VER
-   /* do it this way just to quiet warning */
-   FP_OFF(n_data) = FP_OFF(data);
-   if (FP_SEG(n_data) == FP_SEG(data))
-#else
-   /* this works in MSC also but with lost segment warning */
-   n_data = (png_byte *)data;
-   if ((png_bytep)n_data == data)
-#endif
+   near_data = (png_byte *)CVT_PTR_NOCHECK(data);
+   io_ptr = (FILE *)CVT_PTR(png_ptr->io_ptr);
+   if ((png_bytep)near_data == data)
    {
-      check = fwrite(n_data, 1, (png_size_t)length, (FILE *)(png_ptr->io_ptr));
+      check = fwrite(near_data, 1, length, io_ptr);
    }
    else
    {
       png_byte buf[NEAR_BUF_SIZE];
       png_size_t written, remaining, err;
       check = 0;
-      remaining = (png_size_t)length;
+      remaining = length;
       do
       {
          written = MIN(NEAR_BUF_SIZE, remaining);
          png_memcpy(buf, data, written); /* copy far buffer to near buffer */
-         err = fwrite(buf, 1, written, (FILE *)(png_ptr->io_ptr));
+         err = fwrite(buf, 1, written, io_ptr);
          if (err != written)
             break;
          else
@@ -107,6 +99,7 @@ png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
    }
 }
 
+#endif
 #endif
 
 /* This function is called to output any data pending writing (normally
@@ -116,17 +109,21 @@ png_default_write_data(png_structp png_ptr, png_bytep data, png_uint_32 length)
 void
 png_flush(png_structp png_ptr)
 {
-   if (png_ptr->output_flush_fn)
+   if (png_ptr->output_flush_fn != NULL)
       (*(png_ptr->output_flush_fn))(png_ptr);
 }
 
+#if !defined(PNG_NO_STDIO)
 static void
 png_default_flush(png_structp png_ptr)
 {
-   if ((FILE *)(png_ptr->io_ptr))
-      fflush((FILE *)(png_ptr->io_ptr));
+   FILE *io_ptr;
+   io_ptr = (FILE *)CVT_PTR((png_ptr->io_ptr));
+   if (io_ptr != NULL)
+      fflush(io_ptr);
 }
 #endif
+#endif
 
 /* This function allows the application to supply new output functions for
    libpng if standard C streams aren't being used.
@@ -135,13 +132,13 @@ png_default_flush(png_structp png_ptr)
    png_ptr       - pointer to a png output data structure
    io_ptr        - pointer to user supplied structure containing info about
                    the output functions.  May be NULL.
-   write_data_fn - pointer to a new output function which takes as its
+   write_data_fn - pointer to a new output function that takes as its
                    arguments a pointer to a png_struct, a pointer to
-                   data to be written, and a 32-bit unsigned int which is
+                   data to be written, and a 32-bit unsigned int that is
                    the number of bytes to be written.  The new write
                    function should call png_error(png_ptr, "Error msg")
                    to exit and output any fatal error messages.
-   flush_data_fn - pointer to a new flush function which takes as its
+   flush_data_fn - pointer to a new flush function that takes as its
                    arguments a pointer to a png_struct.  After a call to
                    the flush function, there should be no data in any buffers
                    or pending transmission.  If the output method doesn't do
@@ -156,19 +153,61 @@ png_set_write_fn(png_structp png_ptr, png_voidp io_ptr,
 {
    png_ptr->io_ptr = io_ptr;
 
-   if (write_data_fn)
+#if !defined(PNG_NO_STDIO)
+   if (write_data_fn != NULL)
       png_ptr->write_data_fn = write_data_fn;
    else
       png_ptr->write_data_fn = png_default_write_data;
+#else
+   png_ptr->write_data_fn = write_data_fn;
+#endif
 
 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
-   if (output_flush_fn)
+#if !defined(PNG_NO_STDIO)
+   if (output_flush_fn != NULL)
       png_ptr->output_flush_fn = output_flush_fn;
    else
       png_ptr->output_flush_fn = png_default_flush;
+#else
+   png_ptr->output_flush_fn = output_flush_fn;
+#endif
 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
 
    /* It is an error to read while writing a png file */
-   png_ptr->read_data_fn = NULL;
+   if (png_ptr->read_data_fn != NULL)
+   {
+      png_ptr->read_data_fn = NULL;
+      png_warning(png_ptr,
+         "Attempted to set both read_data_fn and write_data_fn in");
+      png_warning(png_ptr,
+         "the same structure.  Resetting read_data_fn to NULL.");
+   }
 }
 
+#if defined(USE_FAR_KEYWORD)
+#if defined(_MSC_VER)
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+{
+   void *near_ptr;
+   void FAR *far_ptr;
+   FP_OFF(near_ptr) = FP_OFF(ptr);
+   far_ptr = (void FAR *)near_ptr;
+   if(check != 0)
+      if(FP_SEG(ptr) != FP_SEG(far_ptr))
+         png_error(png_ptr,"segment lost in conversion");
+   return(near_ptr);
+}
+#  else
+void *png_far_to_near(png_structp png_ptr,png_voidp ptr, int check)
+{
+   void *near_ptr;
+   void FAR *far_ptr;
+   near_ptr = (void FAR *)ptr;
+   far_ptr = (void FAR *)near_ptr;
+   if(check != 0)
+      if(far_ptr != ptr)
+         png_error(png_ptr,"segment lost in conversion");
+   return(near_ptr);
+}
+#   endif
+#   endif

pngwtran.c

@@ -1,38 +1,68 @@
 
-/* pngwtran.c - transforms the data in a row for png writers
-
-   libpng 1.0 beta 3 - version 0.89
-   For conditions of distribution and use, see copyright notice in png.h
-   Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
-   May 25, 1996
-   */
+/* pngwtran.c - transforms the data in a row for PNG writers
+ *
+ * libpng 1.0.4 - September 19, 1999
+ * For conditions of distribution and use, see copyright notice in png.h
+ * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
+ * Copyright (c) 1996, 1997 Andreas Dilger
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
+ */
 
 #define PNG_INTERNAL
 #include "png.h"
 
-/* transform the data according to the users wishes.  The order of
-   transformations is significant. */
+/* Transform the data according to the user's wishes.  The order of
+ * transformations is significant.
+ */
 void
 png_do_write_transformations(png_structp png_ptr)
 {
+   png_debug(1, "in png_do_write_transformations\n");
+
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   if (png_ptr->transformations & PNG_USER_TRANSFORM)
+      if(png_ptr->write_user_transform_fn != NULL)
+        (*(png_ptr->write_user_transform_fn)) /* user write transform function */
+          (png_ptr,                    /* png_ptr */
+           &(png_ptr->row_info),       /* row_info:     */
+             /*  png_uint_32 width;          width of row */
+             /*  png_uint_32 rowbytes;       number of bytes in row */
+             /*  png_byte color_type;        color type of pixels */
+             /*  png_byte bit_depth;         bit depth of samples */
+             /*  png_byte channels;          number of channels (1-4) */
+             /*  png_byte pixel_depth;       bits per pixel (depth*channels) */
+           png_ptr->row_buf + 1);      /* start of pixel data for row */
+#endif
 #if defined(PNG_WRITE_FILLER_SUPPORTED)
    if (png_ptr->transformations & PNG_FILLER)
-      png_do_write_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
+      png_do_strip_filler(&(png_ptr->row_info), png_ptr->row_buf + 1,
          png_ptr->flags);
 #endif
+#if defined(PNG_WRITE_PACKSWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_PACKSWAP)
+      png_do_packswap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
 #if defined(PNG_WRITE_PACK_SUPPORTED)
    if (png_ptr->transformations & PNG_PACK)
       png_do_pack(&(png_ptr->row_info), png_ptr->row_buf + 1,
-         png_ptr->bit_depth);
+         (png_uint_32)png_ptr->bit_depth);
+#endif
+#if defined(PNG_WRITE_SWAP_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_BYTES)
+      png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
 #if defined(PNG_WRITE_SHIFT_SUPPORTED)
    if (png_ptr->transformations & PNG_SHIFT)
       png_do_shift(&(png_ptr->row_info), png_ptr->row_buf + 1,
          &(png_ptr->shift));
 #endif
-#if defined(PNG_WRITE_SWAP_SUPPORTED)
-   if (png_ptr->transformations & PNG_SWAP_BYTES)
-      png_do_swap(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_INVERT_ALPHA)
+      png_do_write_invert_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
+#endif
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
+   if (png_ptr->transformations & PNG_SWAP_ALPHA)
+      png_do_write_swap_alpha(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
 #if defined(PNG_WRITE_BGR_SUPPORTED)
    if (png_ptr->transformations & PNG_BGR)
@@ -45,32 +75,37 @@ png_do_write_transformations(png_structp png_ptr)
 }
 
 #if defined(PNG_WRITE_PACK_SUPPORTED)
-/* pack pixels into bytes.  Pass the true bit depth in bit_depth.  The
-   row_info bit depth should be 8 (one pixel per byte).  The channels
-   should be 1 (this only happens on grayscale and paletted images) */
+/* Pack pixels into bytes.  Pass the true bit depth in bit_depth.  The
+ * row_info bit depth should be 8 (one pixel per byte).  The channels
+ * should be 1 (this only happens on grayscale and paletted images).
+ */
 void
-png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
+png_do_pack(png_row_infop row_info, png_bytep row, png_uint_32 bit_depth)
 {
-   if (row_info && row && row_info->bit_depth == 8 &&
+   png_debug(1, "in png_do_pack\n");
+   if (row_info->bit_depth == 8 &&
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+       row != NULL && row_info != NULL &&
+#endif
       row_info->channels == 1)
    {
-      switch (bit_depth)
+      switch ((int)bit_depth)
       {
          case 1:
          {
-            png_bytep sp;
-            png_bytep dp;
-            int mask;
-            png_int_32 i;
-            int v;
+            png_bytep sp, dp;
+            int mask, v;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
 
             sp = row;
             dp = row;
             mask = 0x80;
             v = 0;
-            for (i = 0; i < row_info->width; i++)
+
+            for (i = 0; i < row_width; i++)
             {
-               if (*sp)
+               if (*sp != 0)
                   v |= mask;
                sp++;
                if (mask > 1)
@@ -89,19 +124,19 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
          }
          case 2:
          {
-            png_bytep sp;
-            png_bytep dp;
-            int shift;
-            png_int_32 i;
-            int v;
-            png_byte value;
+            png_bytep sp, dp;
+            int shift, v;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
 
             sp = row;
             dp = row;
             shift = 6;
             v = 0;
-            for (i = 0; i < row_info->width; i++)
+            for (i = 0; i < row_width; i++)
             {
+               png_byte value;
+
                value = (png_byte)(*sp & 0x3);
                v |= (value << shift);
                if (shift == 0)
@@ -121,19 +156,19 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
          }
          case 4:
          {
-            png_bytep sp;
-            png_bytep dp;
-            int shift;
-            png_int_32 i;
-            int v;
-            png_byte value;
+            png_bytep sp, dp;
+            int shift, v;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
 
             sp = row;
             dp = row;
             shift = 4;
             v = 0;
-            for (i = 0; i < row_info->width; i++)
+            for (i = 0; i < row_width; i++)
             {
+               png_byte value;
+
                value = (png_byte)(*sp & 0xf);
                v |= (value << shift);
 
@@ -154,8 +189,8 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
             break;
          }
       }
-      row_info->bit_depth = bit_depth;
-      row_info->pixel_depth = (png_uint_16)(bit_depth * row_info->channels);
+      row_info->bit_depth = (png_byte)bit_depth;
+      row_info->pixel_depth = (png_byte)(bit_depth * row_info->channels);
       row_info->rowbytes =
          ((row_info->width * row_info->pixel_depth + 7) >> 3);
    }
@@ -163,22 +198,27 @@ png_do_pack(png_row_infop row_info, png_bytep row, png_byte bit_depth)
 #endif
 
 #if defined(PNG_WRITE_SHIFT_SUPPORTED)
-/* shift pixel values to take advantage of whole range.  Pass the
-   true number of bits in bit_depth.  The row should be packed
-   according to row_info->bit_depth.  Thus, if you had a row of
-   bit depth 4, but the pixels only had values from 0 to 7, you
-   would pass 3 as bit_depth, and this routine would translate the
-   data to 0 to 15. */
+/* Shift pixel values to take advantage of whole range.  Pass the
+ * true number of bits in bit_depth.  The row should be packed
+ * according to row_info->bit_depth.  Thus, if you had a row of
+ * bit depth 4, but the pixels only had values from 0 to 7, you
+ * would pass 3 as bit_depth, and this routine would translate the
+ * data to 0 to 15.
+ */
 void
 png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
 {
-   if (row && row_info &&
+   png_debug(1, "in png_do_shift\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL &&
+#else
+   if (
+#endif
       row_info->color_type != PNG_COLOR_TYPE_PALETTE)
    {
       int shift_start[4], shift_dec[4];
-      int channels;
+      int channels = 0;
 
-      channels = 0;
       if (row_info->color_type & PNG_COLOR_MASK_COLOR)
       {
          shift_start[channels] = row_info->bit_depth - bit_depth->red;
@@ -204,13 +244,13 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
          channels++;
       }
 
-      /* with low row dephts, could only be grayscale, so one channel */
+      /* with low row depths, could only be grayscale, so one channel */
       if (row_info->bit_depth < 8)
       {
-         png_bytep bp;
+         png_bytep bp = row;
          png_uint_32 i;
-         int j;
          png_byte mask;
+         png_uint_32 row_bytes = row_info->rowbytes;
 
          if (bit_depth->gray == 1 && row_info->bit_depth == 2)
             mask = 0x55;
@@ -219,9 +259,10 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
          else
             mask = 0xff;
 
-         for (bp = row, i = 0; i < row_info->rowbytes; i++, bp++)
+         for (i = 0; i < row_bytes; i++, bp++)
          {
-            int v;
+            png_uint_16 v;
+            int j;
 
             v = *bp;
             *bp = 0;
@@ -236,27 +277,25 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
       }
       else if (row_info->bit_depth == 8)
       {
-         png_bytep bp;
+         png_bytep bp = row;
          png_uint_32 i;
-         int j;
+         png_uint_32 istop = channels * row_info->width;
 
-         for (bp = row, i = 0; i < row_info->width; i++)
+         for (i = 0; i < istop; i++, bp++)
          {
-            int c;
 
-            for (c = 0; c < channels; c++, bp++)
+            png_uint_16 v;
+            int j;
+            int c = (int)(i%channels);
+
+            v = *bp;
+            *bp = 0;
+            for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
-               int v;
-
-               v = *bp;
-               *bp = 0;
-               for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
-               {
-                  if (j > 0)
-                     *bp |= (png_byte)((v << j) & 0xff);
-                  else
-                     *bp |= (png_byte)((v >> (-j)) & 0xff);
-               }
+               if (j > 0)
+                  *bp |= (png_byte)((v << j) & 0xff);
+               else
+                  *bp |= (png_byte)((v >> (-j)) & 0xff);
             }
          }
       }
@@ -264,84 +303,195 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
       {
          png_bytep bp;
          png_uint_32 i;
-         int j;
+         png_uint_32 istop = channels * row_info->width;
 
-         for (bp = row, i = 0;
-            i < row_info->width * row_info->channels;
-            i++)
+         for (bp = row, i = 0; i < istop; i++)
          {
-            int c;
+            int c = (int)(i%channels);
+            png_uint_16 value, v;
+            int j;
 
-            for (c = 0; c < channels; c++, bp += 2)
+            v = ((png_uint_16)(*bp) << 8) + *(bp + 1);
+            value = 0;
+            for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
-               png_uint_16 value, v;
-
-               v = (png_uint_16)(((png_uint_16)(*bp) << 8) +
-                  (png_uint_16)(*(bp + 1)));
-               value = 0;
-               for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
-               {
-                  if (j > 0)
-                     value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
-                  else
-                     value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
-               }
-               *bp = (png_byte)(value >> 8);
-               *(bp + 1) = (png_byte)(value & 0xff);
+               if (j > 0)
+                  value |= (png_uint_16)((v << j) & (png_uint_16)0xffff);
+               else
+                  value |= (png_uint_16)((v >> (-j)) & (png_uint_16)0xffff);
             }
+            *bp++ = (png_byte)(value >> 8);
+            *bp++ = (png_byte)(value & 0xff);
          }
       }
    }
 }
 #endif
 
-#ifdef PNG_WRITE_FILLER_SUPPORTED
-/* remove filler byte */
+#if defined(PNG_WRITE_SWAP_ALPHA_SUPPORTED)
 void
-png_do_write_filler(png_row_infop row_info, png_bytep row,
-   png_byte flags)
+png_do_write_swap_alpha(png_row_infop row_info, png_bytep row)
 {
-   if (row && row_info && row_info->color_type == PNG_COLOR_TYPE_RGB &&
-      row_info->bit_depth == 8)
+   png_debug(1, "in png_do_write_swap_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
    {
-      if (flags & PNG_FLAG_FILLER_AFTER)
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
       {
-         png_bytep sp, dp;
-
-         png_uint_32 i;
-
-         for (i = 1, sp = row + 4, dp = row + 3;
-            i < row_info->width;
-            i++)
+         /* This converts from ARGB to RGBA */
+         if (row_info->bit_depth == 8)
          {
-            *dp++ = *sp++;
-            *dp++ = *sp++;
-            *dp++ = *sp++;
-            sp++;
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save;
+            }
+         }
+         /* This converts from AARRGGBB to RRGGBBAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save[2];
+               save[0] = *(sp++);
+               save[1] = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save[0];
+               *(dp++) = save[1];
+            }
          }
-         row_info->channels = 3;
-         row_info->pixel_depth = 24;
-         row_info->rowbytes = row_info->width * 3;
       }
-      else
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
       {
-         png_bytep sp, dp;
-         png_uint_32 i;
-
-         for (i = 0, sp = row, dp = row;
-            i < row_info->width;
-            i++)
+         /* This converts from AG to GA */
+         if (row_info->bit_depth == 8)
          {
-            sp++;
-            *dp++ = *sp++;
-            *dp++ = *sp++;
-            *dp++ = *sp++;
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save;
+            }
+         }
+         /* This converts from AAGG to GGAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               png_byte save[2];
+               save[0] = *(sp++);
+               save[1] = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = save[0];
+               *(dp++) = save[1];
+            }
          }
-         row_info->channels = 3;
-         row_info->pixel_depth = 24;
-         row_info->rowbytes = row_info->width * 3;
       }
    }
 }
 #endif
 
+#if defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED)
+void
+png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
+{
+   png_debug(1, "in png_do_write_invert_alpha\n");
+#if defined(PNG_USELESS_TESTS_SUPPORTED)
+   if (row != NULL && row_info != NULL)
+#endif
+   {
+      if (row_info->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+      {
+         /* This inverts the alpha channel in RGBA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = 255 - *(sp++);
+            }
+         }
+         /* This inverts the alpha channel in RRGGBBAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = 255 - *(sp++);
+               *(dp++) = 255 - *(sp++);
+            }
+         }
+      }
+      else if (row_info->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+      {
+         /* This inverts the alpha channel in GA */
+         if (row_info->bit_depth == 8)
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = 255 - *(sp++);
+            }
+         }
+         /* This inverts the alpha channel in GGAA */
+         else
+         {
+            png_bytep sp, dp;
+            png_uint_32 i;
+            png_uint_32 row_width = row_info->width;
+
+            for (i = 0, sp = dp = row; i < row_width; i++)
+            {
+               *(dp++) = *(sp++);
+               *(dp++) = *(sp++);
+               *(dp++) = 255 - *(sp++);
+               *(dp++) = 255 - *(sp++);
+            }
+         }
+      }
+   }
+}
+#endif

readme.txt

@@ -1,106 +0,0 @@
-readme.txt - for libpng 0.89
-
-This is a bug fix for the third beta version of libpng 1.0.  The
-changes from libpng-0.88 are bug fixes and some changes to the
-API itself to increase robustness with shared libraries.  This
-release is based on libpng-0.88, but has been modified from that
-version by Andreas Dilger <adilger@enel.ucalgary.ca> because the
-original author, Guy Schalnat, has not been able to keep up with
-the time demands of maintaining this library.
-
-The callback functions for the error/warning messages have changed
-since the last release because their implementation was broken,
-and it was thought best to change the API itself (which was only
-introduced in libpng-0.88 itself) to alert the user to the change,
-rather than mislead the user into thinking their application was
-OK after re-compiling.  This means that calls to png_set_message_fn()
-no longer exist, because the previously suggested method of calling
-them before png_read_init() or png_write_init() is now ineffective.
-
-The preferred method of setting the error and warning callbacks
-has been incorporated into the allocation of the png_struct and
-info_struct itself, which allow them to be safely used during the
-initialization of the structure, as well as to keep the size of
-the png_struct internal to the library, rather than at compile time
-of the application.  This will hopefully remove any problems with
-dynamically linked libraries, and should be considered the preferred
-method of creating these structures, although the previous
-initialization API is still available for compatibility.  See libpng.txt
-for more information on the new API.
-
-The changes made to the library, and bugs fixed are based on discussions
-on the PNG implementation mailing list <png-implement@dworking.wustl.edu>
-and not on material submitted to Guy.
-
-For a detailed description on using libpng, read libpng.txt.  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.
-
-You will need zlib 0.95 or later to run this.  zlib is a compression
-library that is useful for more things then just png files.  If
-you need a compression library, check out zlib.h.  There was a bug in
-zlib <= 0.99 which caused it to generate invalid compression streams
-on some occasions.  Later versions of zlib do not have this problem.
-
-zlib should be available at the same place that libpng is.
-If not, it should be at ftp.uu.net in /graphics/png
-Eventually, it will be at ftp.uu.net in /pub/archiving/zip/zlib
-
-You may also want a copy of the PNG specification.  It should
-be available at the same place you picked up libpng.  If it is
-not there, try ftp.uu.net in the /graphics/png directory.
-
-This code is currently being archived at ftp.uu.net in the
-/graphics/png directory, and on CompuServe, Lib 20 (PNG SUPPORT)
-at GO GRAPHSUP.  If you can't find it in any of those places,
-e-mail me, and I'll help you find it.
-
-If you have any code changes, requests, problems, etc., please e-mail
-them to me.  Also, I'd appreciate any make files or project files,
-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, and the
-PNG group.
-
-adilger@enel.ucalgary.ca
-png-implement@dworkin.wustl.edu
-
-You can reach Guy, the original libpng author, at (internet preferred):
-
-internet: schalnat@group42.com
-CompuServe: 75501,1625
-
-Please do not send general questions about PNG.  Send them to
-the address in the specification.  At the same time, please do
-not send libpng questions to that address, send them to me.  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 over a year 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 for version
-1.0, it may be used later.
-
-Good luck, and happy coding.
-
--Guy Eric Schalnat
- Group 42, Inc.
- Internet: schalnat@group42.com
- CompuServe: 75501,1625
- Web: www.group42.com
-

scripts/SCOPTIONS.ppc

@@ -0,0 +1,7 @@
+OPTIMIZE
+OPTPEEP
+OPTTIME
+OPTSCHED
+AUTOREGISTER
+PARMS=REGISTERS
+INCLUDEDIR=hlp:ppc/include

scripts/descrip.mms

@@ -8,9 +8,9 @@ pref = /prefix=all
 
 
 
-OBJS = png.obj, pngrcb.obj, pngrutil.obj, pngtrans.obj, pngwutil.obj,\
-	pngread.obj, pngmem.obj, pngwrite.obj, pngrtran.obj, pngwtran.obj,\
-	pngrio.obj, pngwio.obj, pngerror.obj, pngpread.obj
+OBJS = png.obj, pngset.obj, pngget.obj, pngrutil.obj, pngtrans.obj,\
+	pngwutil.obj, pngread.obj, pngmem.obj, pngwrite.obj, pngrtran.obj,\
+	pngwtran.obj, pngrio.obj, pngwio.obj, pngerror.obj, pngpread.obj
 
 
 CFLAGS= $(C_DEB) $(CC_DEFS) $(PREF)
@@ -35,7 +35,8 @@ clean :
 # Other dependencies.
 png.obj : png.h, pngconf.h
 pngpread.obj : png.h, pngconf.h
-pngrcb.obj : png.h, pngconf.h
+pngset.obj : png.h, pngconf.h
+pngget.obj : png.h, pngconf.h
 pngread.obj : png.h, pngconf.h
 pngrtran.obj : png.h, pngconf.h
 pngrutil.obj : png.h, pngconf.h

scripts/makefile.acorn

@@ -0,0 +1,51 @@
+# Project:   libpng
+
+
+# Toolflags:
+CCflags = -c -depend !Depend -IC:,Zlib: -g -throwback  -DRISCOS  -fnah 
+C++flags = -c -depend !Depend -IC: -throwback
+Linkflags = -aif -c++ -o $@
+ObjAsmflags = -throwback -NoCache -depend !Depend
+CMHGflags = 
+LibFileflags = -c -l -o $@ 
+Squeezeflags = -o $@
+
+
+# Final targets:
+@.libpng-lib:   @.o.png @.o.pngerror @.o.pngrio @.o.pngwio @.o.pngmem \
+	@.o.pngpread @.o.pngset @.o.pngget @.o.pngread @.o.pngrtran \
+	@.o.pngrutil @.o.pngtrans @.o.pngwrite @.o.pngwtran @.o.pngwutil 
+	LibFile $(LibFileflags) @.o.png @.o.pngerror @.o.pngrio @.o.pngrtran \
+	@.o.pngmem @.o.pngpread @.o.pngset @.o.pngget @.o.pngread @.o.pngwio \
+	@.o.pngrutil @.o.pngtrans  @.o.pngwrite @.o.pngwtran @.o.pngwutil 
+@.mm-libpng-lib:   @.mm.png @.mm.pngerror @.mm.pngrio @.mm.pngwio @.mm.pngmem \
+	@.mm.pngpread @.mm.pngset @.mm.pngget @.mm.pngread @.mm.pngrtran \
+	@.mm.pngrutil @.mm.pngtrans @.mm.pngwrite @.mm.pngwtran @.mm.pngwutil 
+	LibFile $(LibFileflags) @.mm.png @.mm.pngerror @.mm.pngrio \
+	@.mm.pngwio @.mm.pngmem @.mm.pngpread @.mm.pngset @.mm.pngget \
+	@.mm.pngread @.mm.pngrtran @.mm.pngrutil @.mm.pngtrans @.mm.pngwrite \
+	@.mm.pngwtran @.mm.pngwutil 
+
+
+# User-editable dependencies:
+# (C) Copyright 1997 Tom Tanner
+Test: @.pngtest 
+	<Prefix$Dir>.pngtest
+	@remove <Prefix$Dir>.pngtest
+
+#It would be nice if you could stop "make" listing from here on!
+@.pngtest:   @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib 
+	Link $(Linkflags) @.o.pngtest @.libpng-lib C:o.Stubs Zlib:zlib_lib 
+
+.SUFFIXES: .o .mm .c
+
+.c.mm:
+	MemCheck.CC cc $(ccflags) -o $@ LibPng:$<
+.c.o:
+	cc $(ccflags) -o $@ $<
+
+
+# Static dependencies:
+
+
+# Dynamic dependencies:

scripts/makefile.amiga

@@ -8,7 +8,7 @@ CC=sc
 # WARNING: a bug in V6.51 causes bad code with OPTGO
 #          So use V6.55 or set NOOPTGO!!!!!!!!!
 CFLAGS= NOSTKCHK PARMS=REG OPTIMIZE OPTGO OPTPEEP OPTINLOCAL OPTINL\
-        OPTLOOP OPTRDEP=4 OPTDEP=4 OPTCOMP=4 DEFINE=PNG_INTERNAL
+	OPTLOOP OPTRDEP=4 OPTDEP=4 OPTCOMP=4 DEFINE=PNG_INTERNAL
 #linker flags
 LDFLAGS= SD ND BATCH
 #link libs
@@ -22,7 +22,7 @@ AR= oml
 # make directory command
 MKDIR= makedir
 
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o pngpread.o \
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o pngpread.o \
 pngread.o pngerror.o pngwrite.o pngrtran.o pngwtran.o pngrio.o pngwio.o pngmem.o
 
 all: libpng.lib pngtest

scripts/makefile.atari

@@ -9,8 +9,9 @@ LBR = png.lib
 LDFLAGS=-lpng -lz -lm
 
 # where make install puts libpng.a and png.h
+prefix=/usr/local
 
-OBJS = $(LBR)(png.o) $(LBR)(pngrcb.o) $(LBR)(pngrutil.o)\
+OBJS = $(LBR)(png.o) $(LBR)(pngset.o) $(LBR)(pngget.o) $(LBR)(pngrutil.o)\
 	$(LBR)(pngtrans.o) $(LBR)(pngwutil.o)\
 	$(LBR)(pngread.o) $(LBR)(pngerror.o) $(LBR)(pngwrite.o)\
 	$(LBR)(pngrtran.o) $(LBR)(pngwtran.o)\
@@ -28,4 +29,5 @@ install: libpng.a
 	-@mkdir $(prefix)/lib
 	cp png.h $(prefix)/include
 	cp pngconf.h $(prefix)/include
-	chmod 644 $(prefix)/include/p
+	chmod 644 $(prefix)/include/png.h
+	chmod 644 $(prefix)/include/pngconf.h

scripts/makefile.beos

@@ -0,0 +1,104 @@
+# makefile for libpng on BeOS x86 ELF with gcc
+# modified from makefile.lnx by Sander Stoks
+# Copyright (C) 1996, 1997 Andreas Dilger
+# Copyright (C) 1999 Greg Roelofs
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=gcc
+
+# Where the zlib library and include files are located
+ZLIBLIB=/usr/local/lib
+ZLIBINC=/usr/local/include
+
+ALIGN=
+# For i386:
+# ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# On BeOS, -O1 is actually better than -O3.  This is a known bug but it's
+# still here in R4.5
+CFLAGS=-I$(ZLIBINC) -Wall -O1 -funroll-loops \
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+# LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz -lm
+LDFLAGS=-L. -Wl,-soname=libpng.so.$(PNGMAJ) -L$(ZLIBLIB) -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+# read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
+# have to change it.
+PNGMAJ = 2
+PNGMIN = 1.0.4
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+# where make install puts libpng.a, libpng.so*, and png.h
+prefix=/usr/local
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS)
+
+.SUFFIXES:      .c .o
+
+all: libpng.a libpng.so pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.so: libpng.so.$(PNGMAJ)
+	ln -sf libpng.so.$(PNGMAJ) libpng.so
+	cp libpng.so* /boot/home/config/lib
+
+libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
+	ln -sf libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+
+libpng.so.$(PNGVER): $(OBJSDLL)
+	$(CC) -L$(ZLIBLIB) -lz -nostart -Wl,-soname,libpng.so.$(PNGMAJ) -o
+libpng.so.$(PNGVER) \
+	 $(OBJSDLL)
+
+pngtest: pngtest.o libpng.so
+	$(CC) -L$(ZLIBLIB) -lz -lpng -o pngtest pngtest.o
+
+test: pngtest
+	./pngtest
+
+install: libpng.a libpng.so.$(PNGVER)
+	-@mkdir $(INCPATH) $(LIBPATH)
+	cp png.h pngconf.h $(INCPATH)
+	chmod 644 $(INCPATH)/png.h $(INCPATH)/pngconf.h
+	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
+	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
+	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
+	(cd $(LIBPATH); ln -sf libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
+	 ln -sf libpng.so.$(PNGMAJ) libpng.so)
+
+clean:
+	/bin/rm -f *.o libpng.a libpng.so* pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h

scripts/makefile.borland

@@ -70,36 +70,38 @@ O=obj
 
 ## variables
 OBJS = \
- png.$(O) \
- pngerror.$(O) \
- pngmem.$(O) \
- pngpread.$(O) \
- pngrcb.$(O) \
- pngread.$(O) \
- pngrio.$(O) \
- pngrtran.$(O) \
- pngrutil.$(O) \
- pngtrans.$(O) \
- pngwrite.$(O) \
- pngwtran.$(O) \
- pngwio.$(O) \
- pngwutil.$(O)
+	png.$(O) \
+	pngerror.$(O) \
+	pngmem.$(O) \
+	pngpread.$(O) \
+	pngset.$(O) \
+	pngget.$(O) \
+	pngread.$(O) \
+	pngrio.$(O) \
+	pngrtran.$(O) \
+	pngrutil.$(O) \
+	pngtrans.$(O) \
+	pngwrite.$(O) \
+	pngwtran.$(O) \
+	pngwio.$(O) \
+	pngwutil.$(O)
 
 LIBOBJS = \
- +png.$(O) \
- +pngerror.$(O) \
- +pngmem.$(O) \
- +pngpread.$(O) \
- +pngread.$(O) \
- +pngrcb.$(O) \
- +pngrio.$(O) \
- +pngrtran.$(O) \
- +pngrutil.$(O) \
- +pngtrans.$(O) \
- +pngwrite.$(O) \
- +pngwtran.$(O) \
- +pngwio.$(O)
- +pngwutil.$(O)
+	+png.$(O) \
+	+pngerror.$(O) \
+	+pngmem.$(O) \
+	+pngpread.$(O) \
+	+pngread.$(O) \
+	+pngset.$(O) \
+	+pngget.$(O) \
+	+pngrio.$(O) \
+	+pngrtran.$(O) \
+	+pngrutil.$(O) \
+	+pngtrans.$(O) \
+	+pngwrite.$(O) \
+	+pngwtran.$(O) \
+	+pngwio.$(O) \
+	+pngwutil.$(O)
 
 LIBNAME=libpng$(MODEL).lib
 
@@ -119,14 +121,15 @@ libpng: $(LIBNAME)
 
 pngtest: pngtest$(MODEL).exe
 
-test:
+test: pngtest$(MODEL).exe
 	pngtest$(MODEL)
 
 
 ## Minor Targets
 
 png.obj: png.c
-pngrcb.obj: pngrcb.c
+pngset.obj: pngset.c
+pngget.obj: pngget.c
 pngread.obj: pngread.c
 pngpread.obj: pngpread.c
 pngrtran.obj: pngrtran.c
@@ -143,7 +146,7 @@ pngwutil.obj: pngwutil.c
 
 $(LIBNAME): $(OBJS)
 	-del $(LIBNAME)
-        $(LIB) $(LIBNAME) @&&|
+	$(LIB) $(LIBNAME) @&&|
 $(LIBOBJS), libpng$(MODEL)
 |
 

scripts/makefile.dec

@@ -0,0 +1,89 @@
+# makefile for libpng on DEC Alpha Unix
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+# read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
+# have to change it.
+PNGMAJ = 2
+PNGMIN = 1.0.4
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+CC=cc
+CFLAGS=-std -w1 -I$(ZLIBINC) -O # -g -DPNG_DEBUG=1
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+#RANLIB=echo
+RANLIB=ranlib
+
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.so libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+libpng.so: libpng.so.$(PNGMAJ)
+	ln -f -s libpng.so.$(PNGMAJ) libpng.so
+
+libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
+	ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+
+libpng.so.$(PNGVER): $(OBJS)
+	$(CC) -shared -o $@ $(OBJS) -L$(ZLIBLIB) -lz -lm
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a libpng.so.$(PNGVER)
+	-@mkdir $(prefix)/include
+	-@mkdir $(prefix)/lib
+	cp png.h $(prefix)/include
+	cp pngconf.h $(prefix)/include
+	chmod 644 $(prefix)/include/png.h
+	chmod 644 $(prefix)/include/pngconf.h
+	cp libpng.a $(prefix)/lib
+	cp libpng.so.$(PNGVER) $(prefix)/lib
+	chmod 644 $(prefix)/lib/libpng.a
+	chmod 644 $(prefix)/lib/libpng.so.$(PNGVER)
+	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
+	(cd $(LIBPATH); ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
+	 ln -f -s libpng.so.$(PNGMAJ) libpng.so)
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png libpng.so*
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+

scripts/makefile.dj2

@@ -1,18 +1,18 @@
-# gcc/DOS makefile for libpng
+# DJGPP (DOS gcc) makefile for libpng
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 # For conditions of distribution and use, see copyright notice in png.h
 
+# where make install puts libpng.a and png.h
+#prefix=/usr/local
+prefix=.
+
 CC=gcc
 CFLAGS=-I../zlib -O
 LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
 
 RANLIB=ranlib
 
-# where make install puts libpng.a and png.h
-#prefix=/usr/local
-prefix=.
-
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
 	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o pngwtran.o \
 	pngmem.o pngerror.o pngpread.o
 
@@ -23,7 +23,7 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
 	coff2exe pngtest
 
 test: pngtest
@@ -38,7 +38,8 @@ pngerror.o: png.h pngconf.h
 pngrio.o: png.h pngconf.h
 pngwio.o: png.h pngconf.h
 pngmem.o: png.h pngconf.h
-pngrcb.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
 pngread.o: png.h pngconf.h
 pngpread.o: png.h pngconf.h
 pngrtran.o: png.h pngconf.h

scripts/makefile.hpux

@@ -0,0 +1,67 @@
+# makefile for libpng, HPUX (10.20 and 11.00)
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42
+# Copyright (C) 1999 Glenn Randers-Pehrson
+# contributed by Jim Rice, Hewlett Packard
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Where the zlib library and include files are located
+ZLIBLIB=/opt/zlib/lib
+ZLIBINC=/opt/zlib/include
+
+CC=cc
+CFLAGS=-I$(ZLIBINC) -O -Ae +DA1.1 +DS2.0
+CCFLAGS=-I$(ZLIBINC) -O -Ae +DA1.1 +DS2.0
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=ranlib
+
+# where make install puts libpng.a and png.h
+prefix=/opt/libpng
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a
+	-@mkdir $(prefix)/include
+	-@mkdir $(prefix)/lib
+	cp png.h $(prefix)/include
+	cp pngconf.h $(prefix)/include
+	chmod 644 $(prefix)/include/png.h
+	chmod 644 $(prefix)/include/pngconf.h
+	cp libpng.a $(prefix)/lib
+	chmod 644 $(prefix)/lib/libpng.a
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h

scripts/makefile.knr

@@ -2,6 +2,14 @@
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 # For conditions of distribution and use, see copyright notice in png.h
 
+# This makefile requires file file ansi2knr.c, which you can get
+# from the Ghostscript ftp site at ftp://ftp.cs.wisc.edu/ghost/
+# If you have libjpeg, you probably already have ansi2knr.c in the jpeg
+# source distribution.
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+
 CC=cc
 CFLAGS=-I../zlib -O
 LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
@@ -11,10 +19,7 @@ ANSI2KNRFLAGS=
 RANLIB=ranlib
 #RANLIB=echo
 
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
 	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
 	pngwtran.o pngmem.o pngerror.o pngpread.o
 
@@ -34,8 +39,8 @@ libpng.a: ansi2knr $(OBJS)
 	ar rc $@  $(OBJS)
 	$(RANLIB) $@
 
-pngtest: pngtest.o libpng.a ansi2knr
-	cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
 
 test: pngtest
 	./pngtest
@@ -60,7 +65,8 @@ pngerror.o: png.h pngconf.h
 pngrio.o: png.h pngconf.h
 pngwio.o: png.h pngconf.h
 pngmem.o: png.h pngconf.h
-pngrcb.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
 pngread.o: png.h pngconf.h
 pngpread.o: png.h pngconf.h
 pngrtran.o: png.h pngconf.h

scripts/makefile.linux

@@ -0,0 +1,105 @@
+# makefile for libpng on Linux ELF with gcc
+# Copyright (C) 1996, 1997 Andreas Dilger
+# Copyright (C) 1998, 1999 Greg Roelofs
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=gcc
+
+# where "make install" puts libpng.a, libpng.so*, png.h and pngconf.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+ALIGN=
+# for i386:
+#ALIGN=-malign-loops=2 -malign-functions=2
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+CFLAGS=-I$(ZLIBINC) -Wall -O3 -funroll-loops \
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+# read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
+# have to change it.
+PNGMAJ = 2
+PNGMIN = 1.0.4
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a libpng.so pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.so: libpng.so.$(PNGMAJ)
+	ln -sf libpng.so.$(PNGMAJ) libpng.so
+
+libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
+	ln -sf libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+
+libpng.so.$(PNGVER): $(OBJSDLL)
+	$(CC) -shared -Wl,-soname,libpng.so.$(PNGMAJ) -o libpng.so.$(PNGVER) \
+	 $(OBJSDLL) -L$(ZLIBLIB) -lz -lm -lc
+
+pngtest: pngtest.o libpng.so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a libpng.so.$(PNGVER)
+	-@mkdir $(INCPATH) $(LIBPATH)
+	cp png.h pngconf.h $(INCPATH)
+	chmod 644 $(INCPATH)/png.h $(INCPATH)/pngconf.h
+	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
+	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
+	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
+	(cd $(LIBPATH); ln -sf libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
+	 ln -sf libpng.so.$(PNGMAJ) libpng.so)
+
+clean:
+	/bin/rm -f *.o libpng.a libpng.so* pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h

scripts/makefile.mips

@@ -2,6 +2,9 @@
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 # For conditions of distribution and use, see copyright notice in png.h
 
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+
 CC=cc
 CFLAGS=-I../zlib -O -systype sysv -DSYSV -w -Dmips
 #CFLAGS=-O
@@ -10,10 +13,7 @@ LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
 #RANLIB=ranlib
 RANLIB=echo
 
-# where make install puts libpng.a and png.h
-prefix=/usr/local
-
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
 	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
 	pngwtran.o pngmem.o pngerror.o pngpread.o
 
@@ -24,7 +24,7 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	cc -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
 
 test: pngtest
 	./pngtest
@@ -49,7 +49,8 @@ pngerror.o: png.h pngconf.h
 pngrio.o: png.h pngconf.h
 pngwio.o: png.h pngconf.h
 pngmem.o: png.h pngconf.h
-pngrcb.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
 pngread.o: png.h pngconf.h
 pngpread.o: png.h pngconf.h
 pngrtran.o: png.h pngconf.h

scripts/makefile.msc

@@ -5,7 +5,7 @@
 
 # ------------- Microsoft C 5.1 and later -------------
 MODEL=-AL
-CFLAGS=-Oait -Gs -nologo -W2 $(MODEL) -I..\zlib
+CFLAGS=-Oait -Gs -nologo -W3 $(MODEL) -I..\zlib
 #-Ox generates bad code with MSC 5.1
 CC=cl
 LD=link
@@ -16,60 +16,65 @@ O=.obj
 ERRFILE= >> pngerrs
 
 # variables
-OBJS1 = png$(O) pngrcb$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O) pngmem$(O) pngpread$(O)
-OBJS2 = pngread$(O) pngerror$(O) pngwrite$(O) pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+OBJS1 = png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2 = pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3 = pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
 
 all: libpng.lib
 
 png$(O): png.h pngconf.h
 		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
-pngrcb$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+pngset$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngread$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngpread$(O): png.h pngconf.h
 		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngrtran$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngrutil$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngerror$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngmem$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngrio$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngwio$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngtest$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngtrans$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngwrite$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngwtran$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngwutil$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
-libpng.lib: $(OBJS1) $(OBJS2)
-        del libpng.lib
+libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	del libpng.lib
 	lib libpng $(OBJS1);
 	lib libpng $(OBJS2);
+	lib libpng $(OBJS3);
 
 pngtest.exe: pngtest.obj libpng.lib 
 	$(LD) $(LDFLAGS) pngtest.obj,,,libpng.lib ..\zlib\zlib.lib ;

scripts/makefile.os2

@@ -0,0 +1,69 @@
+# makefile for libpng on OS/2 with gcc
+# For conditions of distribution and use, see copyright notice in png.h
+
+# Related files: pngos2.def
+
+CC=gcc -Zomf -s
+
+# Where the zlib library and include files are located
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+CFLAGS=-I$(ZLIBINC) -Wall -O6 -funroll-loops -malign-loops=2 \
+	-malign-functions=2 #$(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lzdll -Zcrtdll
+AR=emxomfar
+
+PNGLIB=png.lib
+IMPLIB=emximp
+SHAREDLIB=png.dll
+SHAREDLIBIMP=pngdll.lib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+.SUFFIXES:      .c .o
+
+all: $(PNGLIB) $(SHAREDLIB) $(SHAREDLIBIMP)
+
+$(PNGLIB): $(OBJS)
+	$(AR) rc $@ $(OBJS)
+
+$(SHAREDLIB): $(OBJS) pngos2.def
+	$(CC) $(LDFLAGS) -Zdll -o $@ $^
+
+$(SHAREDLIBIMP): pngos2.def
+	$(IMPLIB) -o $@ $^
+
+pngtest.exe: pngtest.o png.dll pngdll.lib
+	$(CC) -o $@ $(CFLAGS) $< $(LDFLAGS)
+
+test: pngtest.exe
+	./pngtest.exe
+
+clean:
+	rm -f *.o $(PNGLIB) png.dll pngdll.lib pngtest.exe pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h

scripts/makefile.sco

@@ -0,0 +1,98 @@
+# makefile for SCO OSr5  ELF and Unixware 7 with Native cc
+# Contributed by Mike Hopkirk (hops@sco.com) modified from Makefile.lnx
+#   force ELF build dynamic linking, SONAME setting in lib and RPATH in app
+# Copyright (C) 1996, 1997 Andreas Dilger
+# Copyright (C) 1998 Greg Roelofs
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=cc
+
+# where make install puts libpng.a, libpng.so*, and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CFLAGS= -dy -belf -I$(ZLIBINC) -O3 
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+# read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
+# have to change it.
+PNGMAJ = 2
+PNGMIN = 1.0.4
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -KPIC -o $@ $*.c
+
+all: libpng.a libpng.so pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.so: libpng.so.$(PNGMAJ)
+	ln -f -s libpng.so.$(PNGMAJ) libpng.so
+
+libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
+	ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+
+libpng.so.$(PNGVER): $(OBJSDLL)
+	$(CC) -G  -Wl,-h,libpng.so.$(PNGMAJ) -o libpng.so.$(PNGVER) \
+	 $(OBJSDLL)
+
+pngtest: pngtest.o libpng.so
+	LD_RUN_PATH=.:$(ZLIBLIB) $(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a libpng.so.$(PNGVER)
+	-@mkdir $(INCPATH) $(LIBPATH)
+	cp png.h pngconf.h $(INCPATH)
+	chmod 644 $(INCPATH)/png.h $(INCPATH)/pngconf.h
+	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
+	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
+	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
+	(cd $(LIBPATH); ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
+	 ln -f -s libpng.so.$(PNGMAJ) libpng.so)
+
+clean:
+	/bin/rm -f *.o libpng.a libpng.so* pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h

scripts/makefile.sgi

@@ -2,18 +2,27 @@
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 # For conditions of distribution and use, see copyright notice in png.h
 
-CC=cc
-CFLAGS=-I../zlib -O
-LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
-
-#RANLIB=ranlib
-RANLIB=echo
-
 # where make install puts libpng.a and png.h
 prefix=/usr/local
 
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
-	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CC=cc
+
+WARNMORE=-fullwarn
+# You can add the -n32 option; then zlib must also be compiled with -n32
+CFLAGS=-I$(ZLIBINC) -O $(WARNMORE) # -g -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=echo
+#RANLIB=ranlib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
 	pngwtran.o pngmem.o pngerror.o pngpread.o
 
 all: libpng.a pngtest
@@ -23,7 +32,7 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
 
 test: pngtest
 	./pngtest
@@ -48,7 +57,8 @@ pngerror.o: png.h pngconf.h
 pngrio.o: png.h pngconf.h
 pngwio.o: png.h pngconf.h
 pngmem.o: png.h pngconf.h
-pngrcb.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
 pngread.o: png.h pngconf.h
 pngrtran.o: png.h pngconf.h
 pngrutil.o: png.h pngconf.h

scripts/makefile.solaris

@@ -0,0 +1,109 @@
+# makefile for libpng on Solaris 2.x with gcc
+# Contributed by William L. Sebok, based on makefile.lnx
+# Copyright (C) 1996, 1997 Andreas Dilger
+# Copyright (C) 1998 Greg Roelofs
+# For conditions of distribution and use, see copyright notice in png.h
+
+CC=gcc
+
+# The commands "CC" and "LD" must NOT refer to /usr/ucb/cc and /usr/ucb/ld.
+# If they do, you need to adjust your PATH environment variable.
+# The environment variable LD_LIBRARY_PATH should not be set at all.  If
+# it is, things are likely to break.
+
+# Where make install puts libpng.a, libpng.so*, and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+# Changing these to ../zlib poses a security risk.  If you want
+# to have zlib in an adjacent directory, specify the full path instead of "..".
+#ZLIBLIB=../zlib
+#ZLIBINC=../zlib
+
+ZLIBLIB=/usr/local/lib
+ZLIBINC=/usr/local/include
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+CFLAGS=-I$(ZLIBINC) -Wall -O3 \
+	# $(WARNMORE) -g -DPNG_DEBUG=5
+LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng -lz -lm
+
+#RANLIB=ranlib
+RANLIB=echo
+
+# read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
+# have to change it.
+PNGMAJ = 2
+PNGMIN = 1.0.4
+PNGVER = $(PNGMAJ).$(PNGMIN)
+
+INCPATH=$(prefix)/include
+LIBPATH=$(prefix)/lib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+OBJSDLL = $(OBJS:.o=.pic.o)
+
+.SUFFIXES:      .c .o .pic.o
+
+.c.pic.o:
+	$(CC) -c $(CFLAGS) -fPIC -o $@ $*.c
+
+all: libpng.a libpng.so pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@ $(OBJS)
+	$(RANLIB) $@
+
+libpng.so: libpng.so.$(PNGMAJ)
+	ln -f -s libpng.so.$(PNGMAJ) libpng.so
+
+libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
+	ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+
+libpng.so.$(PNGVER): $(OBJSDLL)
+	$(LD) -G -L$(ZLIBLIB) -R$(ZLIBLIB) -h libpng.so.$(PNGMAJ) \
+	 -o libpng.so.$(PNGVER) $(OBJSDLL) -lz
+
+pngtest: pngtest.o libpng.so
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a libpng.so.$(PNGVER)
+	-@mkdir $(INCPATH) $(LIBPATH)
+	cp png.h pngconf.h $(INCPATH)
+	chmod 644 $(INCPATH)/png.h $(INCPATH)/pngconf.h
+	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
+	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
+	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
+	(cd $(LIBPATH); ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
+	 ln -f -s libpng.so.$(PNGMAJ) libpng.so)
+
+clean:
+	/bin/rm -f *.o libpng.a libpng.so* pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o png.pic.o: png.h pngconf.h
+pngerror.o pngerror.pic.o: png.h pngconf.h
+pngrio.o pngrio.pic.o: png.h pngconf.h
+pngwio.o pngwio.pic.o: png.h pngconf.h
+pngmem.o pngmem.pic.o: png.h pngconf.h
+pngset.o pngset.pic.o: png.h pngconf.h
+pngget.o pngget.pic.o: png.h pngconf.h
+pngread.o pngread.pic.o: png.h pngconf.h
+pngrtran.o pngrtran.pic.o: png.h pngconf.h
+pngrutil.o pngrutil.pic.o: png.h pngconf.h
+pngtrans.o pngtrans.pic.o: png.h pngconf.h
+pngwrite.o pngwrite.pic.o: png.h pngconf.h
+pngwtran.o pngwtran.pic.o: png.h pngconf.h
+pngwutil.o pngwutil.pic.o: png.h pngconf.h
+pngpread.o pngpread.pic.o: png.h pngconf.h
+
+pngtest.o: png.h pngconf.h

scripts/makefile.std

@@ -2,17 +2,23 @@
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 # For conditions of distribution and use, see copyright notice in png.h
 
-CC=cc
-CFLAGS=-I../zlib -O
-LDFLAGS=-L. -L../zlib/ -lpng -lz -lm
-
-#RANLIB=ranlib
-RANLIB=echo
-
 # where make install puts libpng.a and png.h
 prefix=/usr/local
 
-OBJS = png.o pngrcb.o pngrutil.o pngtrans.o pngwutil.o \
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+CC=cc
+CFLAGS=-I$(ZLIBINC) -O # -g -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+#RANLIB=echo
+RANLIB=ranlib
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
 	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
 	pngwtran.o pngmem.o pngerror.o pngpread.o
 
@@ -23,7 +29,7 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 pngtest: pngtest.o libpng.a
-	$(CC) -o pngtest $(CCFLAGS) pngtest.o $(LDFLAGS)
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
 
 test: pngtest
 	./pngtest
@@ -48,7 +54,8 @@ pngerror.o: png.h pngconf.h
 pngrio.o: png.h pngconf.h
 pngwio.o: png.h pngconf.h
 pngmem.o: png.h pngconf.h
-pngrcb.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
 pngread.o: png.h pngconf.h
 pngrtran.o: png.h pngconf.h
 pngrutil.o: png.h pngconf.h

scripts/makefile.sunos

@@ -0,0 +1,72 @@
+# makefile for libpng
+# Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
+# For conditions of distribution and use, see copyright notice in png.h
+
+# where make install puts libpng.a and png.h
+prefix=/usr/local
+
+# Where the zlib library and include files are located
+#ZLIBLIB=/usr/local/lib
+#ZLIBINC=/usr/local/include
+ZLIBLIB=../zlib
+ZLIBINC=../zlib
+
+
+WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow -Wconversion \
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes
+CC=gcc
+CFLAGS=-I$(ZLIBINC) -O # $(WARNMORE) -DPNG_DEBUG=5
+LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lz -lm
+
+RANLIB=ranlib
+#RANLIB=echo
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o \
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
+
+all: libpng.a pngtest
+
+libpng.a: $(OBJS)
+	ar rc $@  $(OBJS)
+	$(RANLIB) $@
+
+pngtest: pngtest.o libpng.a
+	$(CC) -o pngtest $(CFLAGS) pngtest.o $(LDFLAGS)
+
+test: pngtest
+	./pngtest
+
+install: libpng.a
+	-@mkdir $(prefix)/include
+	-@mkdir $(prefix)/lib
+	cp png.h $(prefix)/include
+	cp pngconf.h $(prefix)/include
+	chmod 644 $(prefix)/include/png.h
+	chmod 644 $(prefix)/include/pngconf.h
+	cp libpng.a $(prefix)/lib
+	chmod 644 $(prefix)/lib/libpng.a
+
+clean:
+	rm -f *.o libpng.a pngtest pngout.png
+
+# DO NOT DELETE THIS LINE -- make depend depends on it.
+
+png.o: png.h pngconf.h
+pngerror.o: png.h pngconf.h
+pngrio.o: png.h pngconf.h
+pngwio.o: png.h pngconf.h
+pngmem.o: png.h pngconf.h
+pngset.o: png.h pngconf.h
+pngget.o: png.h pngconf.h
+pngread.o: png.h pngconf.h
+pngrtran.o: png.h pngconf.h
+pngrutil.o: png.h pngconf.h
+pngtest.o: png.h pngconf.h
+pngtrans.o: png.h pngconf.h
+pngwrite.o: png.h pngconf.h
+pngwtran.o: png.h pngconf.h
+pngwutil.o: png.h pngconf.h
+pngpread.o: png.h pngconf.h
+

scripts/makefile.turboc3

@@ -0,0 +1,82 @@
+# Makefile for libpng
+# TurboC++ 3.0 (Note: All modules are compiled in C mode)
+
+# To use, do "make -fmakefile.tc3"
+
+# ------------- Turbo C++ 3.0 -------------
+MODEL=-ml
+CFLAGS=-O2 -Z $(MODEL) -I..\zlib
+CC=tcc
+LD=tcc
+LIB=tlib
+LDFLAGS=$(MODEL) -L..\zlib
+O=.obj
+E=.exe
+
+# variables
+OBJS1 = png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2 = pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3 = pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+OBJSL1 = +png$(O) +pngset$(O) +pngget$(O) +pngrutil$(O) +pngtrans$(O)
+OBJSL2 = +pngwutil$(O) +pngmem$(O) +pngpread$(O) +pngread$(O) +pngerror$(O)
+OBJSL3 = +pngwrite$(O) +pngrtran$(O) +pngwtran$(O) +pngrio$(O) +pngwio$(O)
+
+all: libpng.lib pngtest.exe
+
+png$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngset$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngget$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngread$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngpread$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngrtran$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngrutil$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c
+
+pngerror$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngmem$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngrio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngtest$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c
+
+libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	$(LIB) libpng +$(OBJSL1)
+	$(LIB) libpng +$(OBJSL2)
+	$(LIB) libpng +$(OBJSL3)
+
+pngtest$(E): pngtest$(O) libpng.lib
+	$(CC) $(LDFLAGS) pngtest.obj libpng.lib zlib.lib
+
+# End of makefile for libpng

scripts/makefile.watcom

@@ -0,0 +1,88 @@
+# Makefile for libpng
+# Watcom 10.0 and later 32-bit protected mode flat memory model
+
+# Adapted by Pawel Mrochen, based on makefile.msc
+# For conditions of distribution and use, see copyright notice in png.h
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+
+# To use, do "wmake /f scripts\makefile.wat"
+
+# ------------- Watcom 10.0 and later -------------
+MODEL=-mf
+CFLAGS= $(MODEL) -5r -fp5 -fpi87 -oneatx -i=..\zlib
+CC=wcc386
+LD=wcl386
+LIB=wlib -b -c
+LDFLAGS=
+O=.obj
+
+#uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs
+
+# variables
+OBJS1 = png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2 = pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3 = pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O)
+
+all: test
+
+png$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	$(LIB) -n libpng.lib $(OBJS1)
+	$(LIB) libpng.lib $(OBJS2)
+	$(LIB) libpng.lib $(OBJS3)
+
+pngtest.exe: pngtest.obj libpng.lib
+	$(LD) $(LDFLAGS) pngtest.obj libpng.lib ..\zlib\zlib.lib
+
+test: pngtest.exe .symbolic
+	pngtest
+
+# End of makefile for libpng

scripts/makefile.win32vc

@@ -0,0 +1,88 @@
+# makefile for libpng
+# Copyright (C) 1998 Tim Wegner
+# For conditions of distribution and use, see copyright notice in png.h
+# Assumes that zlib.lib, zconf.h, and zlib.h have been copied to ..\zlib
+# To use, do "nmake /f scripts\makefile.w32"
+
+# ------------- Microsoft Visual C++ 4.0 and later -------------
+MODEL=- 
+CFLAGS=-DPNG_USE_PNGVCRD -Ox -GA3s -nologo -W3 -I..\zlib
+
+CC=cl
+LD=link
+LDFLAGS= 
+O=.obj
+
+#uncomment next to put error messages in a file
+#ERRFILE= >> pngerrs
+
+# variables
+OBJS1 = png$(O) pngset$(O) pngget$(O) pngrutil$(O) pngtrans$(O) pngwutil$(O)
+OBJS2 = pngmem$(O) pngpread$(O) pngread$(O) pngerror$(O) pngwrite$(O)
+OBJS3 = pngrtran$(O) pngwtran$(O) pngrio$(O) pngwio$(O) pngvcrd$(O)
+
+all: libpng.lib
+
+png$(O): png.h pngconf.h
+		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngset$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngget$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngpread$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrutil$(O): png.h pngconf.h pngasmrd.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngvcrd$(O): png.h pngconf.h pngasmrd.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngerror$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngmem$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngrio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwio$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtest$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngtrans$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwrite$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwtran$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+pngwutil$(O): png.h pngconf.h
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+
+libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
+	del libpng.lib
+	lib /OUT:libpng.lib $(OBJS1) $(OBJS2) $(OBJS3)
+
+pngtest.exe: pngtest.obj libpng.lib 
+	$(LD) $(LDFLAGS) pngtest.obj libpng.lib ..\zlib\zlib.lib /OUT:pngtest.exe /SUBSYSTEM:CONSOLE
+
+test: pngtest.exe
+	pngtest
+
+# End of makefile for libpng
+

scripts/makevms.com

@@ -35,43 +35,45 @@ $ if f$search("SYS$SYSTEM:MMS.EXE").eqs.""
 $  then
 $   dele pngtest.obj;*
 $   CALL MAKE png.OBJ "cc ''CCOPT' png" -
-                png.c png.h pngconf.h   
+	png.c png.h pngconf.h   
 $   CALL MAKE pngpread.OBJ "cc ''CCOPT' pngpread" -
 					 pngpread.c png.h pngconf.h
-$   CALL MAKE pngrcb.OBJ "cc ''CCOPT' pngrcb" -
-                pngrcb.c png.h pngconf.h
+$   CALL MAKE pngset.OBJ "cc ''CCOPT' pngset" -
+	pngset.c png.h pngconf.h
+$   CALL MAKE pngget.OBJ "cc ''CCOPT' pngget" -
+	pngget.c png.h pngconf.h
 $   CALL MAKE pngread.OBJ "cc ''CCOPT' pngread" -
-                pngread.c png.h pngconf.h
+	pngread.c png.h pngconf.h
 $   CALL MAKE pngpread.OBJ "cc ''CCOPT' pngpread" -
 					 pngpread.c png.h pngconf.h
 $   CALL MAKE pngrtran.OBJ "cc ''CCOPT' pngrtran" -
-                pngrtran.c png.h pngconf.h
+	pngrtran.c png.h pngconf.h
 $   CALL MAKE pngrutil.OBJ "cc ''CCOPT' pngrutil" -
-                pngrutil.c png.h pngconf.h
+	pngrutil.c png.h pngconf.h
 $   CALL MAKE pngerror.OBJ "cc ''CCOPT' pngerror" -
-                pngerror.c png.h pngconf.h
+	pngerror.c png.h pngconf.h
 $   CALL MAKE pngmem.OBJ "cc ''CCOPT' pngmem" -
-                pngmem.c png.h pngconf.h
+	pngmem.c png.h pngconf.h
 $   CALL MAKE pngrio.OBJ "cc ''CCOPT' pngrio" -
-                pngrio.c png.h pngconf.h
+	pngrio.c png.h pngconf.h
 $   CALL MAKE pngwio.OBJ "cc ''CCOPT' pngwio" -
-                pngwio.c png.h pngconf.h
+	pngwio.c png.h pngconf.h
 $   CALL MAKE pngtrans.OBJ "cc ''CCOPT' pngtrans" -
-                pngtrans.c png.h pngconf.h
+	pngtrans.c png.h pngconf.h
 $   CALL MAKE pngwrite.OBJ "cc ''CCOPT' pngwrite" -
-                pngwrite.c png.h pngconf.h
+	pngwrite.c png.h pngconf.h
 $   CALL MAKE pngwtran.OBJ "cc ''CCOPT' pngwtran" -
-                pngwtran.c png.h pngconf.h
+	pngwtran.c png.h pngconf.h
 $   CALL MAKE pngwutil.OBJ "cc ''CCOPT' pngwutil" -
-                pngwutil.c png.h pngconf.h
+	pngwutil.c png.h pngconf.h
 $   write sys$output "Building Libpng ..."
 $   CALL MAKE libpng.OLB "lib/crea libpng.olb *.obj" *.OBJ
 $   write sys$output "Building pngtest..."
 $   CALL MAKE pngtest.OBJ "cc ''CCOPT' pngtest" -
-                pngtest.c png.h pngconf.h
+	pngtest.c png.h pngconf.h
 $   call make pngtest.exe - 
-                "LINK pngtest,libpng.olb/lib,''zlibsrc'libgz.olb/lib" - 
-                pngtest.obj libpng.olb
+	"LINK pngtest,libpng.olb/lib,''zlibsrc'libgz.olb/lib" - 
+	pngtest.obj libpng.olb
 $   write sys$output "Testing Libpng..."
 $   run pngtest
 $  else

scripts/pngdef.pas

@@ -0,0 +1,722 @@
+unit pngdef;
+
+interface
+
+const
+  PNG_LIBPNG_VER_STRING = '1.0.4';
+  PNG_LIBPNG_VER        =  10004;
+
+type
+  png_uint_32 = Cardinal;
+  png_int_32  = Longint;
+  png_uint_16 = Word;
+  png_int_16  = Smallint;
+  png_byte    = Byte;
+  png_size_t  = png_uint_32;
+  png_charpp  = ^png_charp;
+  png_charp   = PChar;
+  float       = single;
+  int         = Integer;
+  png_bytepp  = ^png_bytep;
+  png_bytep   = ^png_byte;
+  png_uint_16p = ^png_uint_16;
+  png_uint_16pp = ^png_uint_16p;
+  png_voidp    = pointer;
+  time_t       = Longint;
+  png_doublep  = ^png_double;
+  png_double   = double;
+
+  user_error_ptr  = Pointer;
+  png_error_ptrp = ^png_error_ptr;
+  png_error_ptr  = procedure(png_ptr: Pointer; msg: Pointer);
+             stdcall;
+  png_rw_ptrp = ^png_rw_ptr;
+  png_rw_ptr = procedure(png_ptr: Pointer; data: Pointer;
+                         length: png_size_t);
+             stdcall;
+  png_flush_ptrp = ^png_flush_ptr;
+  png_flush_ptr = procedure(png_ptr: Pointer);
+             stdcall;
+  png_progressive_info_ptrp = ^png_progressive_info_ptr;
+  png_progressive_info_ptr  = procedure(png_ptr: Pointer;
+                                        info_ptr: Pointer);
+             stdcall;
+  png_progressive_end_ptrp  = ^png_progressive_end_ptr;
+  png_progressive_end_ptr   = procedure(png_ptr: Pointer;
+                                        info_ptr: Pointer);
+             stdcall;
+  png_progressive_row_ptrp  = ^png_progressive_row_ptr;
+  png_progressive_row_ptr   = procedure(png_ptr: Pointer;
+                                data: Pointer; length: png_uint_32;
+                                count: int);
+             stdcall;
+  png_read_status_ptr = procedure(png_ptr: Pointer;
+                          row_number: png_uint_32; pass: int);
+             stdcall;
+  png_write_status_ptr = procedure(png_ptr: Pointer;
+                           row_number: png_uint_32; pass: int);
+             stdcall;
+  png_user_transform_ptr = procedure(png_ptr: Pointer;
+                             row_info: Pointer; data: png_bytep);
+             stdcall;
+
+  png_colorpp = ^png_colorp;
+  png_colorp = ^png_color;
+  png_color = packed record
+    red, green, blue: png_byte;
+    end;
+
+  png_color_16pp = ^png_color_16p;
+  png_color_16p = ^png_color_16;
+  png_color_16 = packed record
+    index: png_byte;                 //used for palette files
+    red, green, blue: png_uint_16;   //for use in red green blue files
+    gray: png_uint_16;               //for use in grayscale files
+    end;
+
+  png_color_8pp = ^png_color_8p;
+  png_color_8p = ^png_color_8;
+  png_color_8 = packed record
+    red, green, blue: png_byte;   //for use in red green blue files
+    gray: png_byte;               //for use in grayscale files
+    alpha: png_byte;              //for alpha channel files
+    end;
+
+  png_textpp = ^png_textp;
+  png_textp = ^png_text;
+  png_text = packed record
+    compression: int;            //compression value
+    key: png_charp;              //keyword, 1-79 character description of "text"
+    text: png_charp;             //comment, may be empty ("")
+    text_length: png_size_t;     //length of text field
+    end;
+
+  png_timepp = ^png_timep;
+  png_timep = ^png_time;
+  png_time = packed record
+    year: png_uint_16;           //yyyy
+    month: png_byte;             //1..12
+    day: png_byte;               //1..31
+    hour: png_byte;              //0..23
+    minute: png_byte;            //0..59
+    second: png_byte;            //0..60 (leap seconds)
+    end;
+
+  png_infopp = ^png_infop;
+  png_infop = Pointer;
+
+  png_row_infopp = ^png_row_infop;
+  png_row_infop = ^png_row_info;
+  png_row_info = packed record
+    width: png_uint_32;          //width of row
+    rowbytes: png_size_t;        //number of bytes in row
+    color_type: png_byte;        //color type of row
+    bit_depth: png_byte;         //bit depth of row
+    channels: png_byte;          //number of channels (1, 2, 3, or 4)
+    pixel_depth: png_byte;       //bits per pixel (depth * channels)
+    end;
+
+  png_structpp = ^png_structp;
+  png_structp = Pointer;
+
+const
+
+// Supported compression types for text in PNG files (tEXt, and zTXt).
+// The values of the PNG_TEXT_COMPRESSION_ defines should NOT be changed.
+
+  PNG_TEXT_COMPRESSION_NONE_WR = -3;
+  PNG_TEXT_COMPRESSION_zTXt_WR = -2;
+  PNG_TEXT_COMPRESSION_NONE    = -1;
+  PNG_TEXT_COMPRESSION_zTXt    = 0;
+
+// These describe the color_type field in png_info.
+// color type masks
+
+  PNG_COLOR_MASK_PALETTE   = 1;
+  PNG_COLOR_MASK_COLOR     = 2;
+  PNG_COLOR_MASK_ALPHA     = 4;
+
+// color types.  Note that not all combinations are legal
+
+  PNG_COLOR_TYPE_GRAY       = 0;
+  PNG_COLOR_TYPE_PALETTE    = PNG_COLOR_MASK_COLOR or
+                              PNG_COLOR_MASK_PALETTE;
+  PNG_COLOR_TYPE_RGB        = PNG_COLOR_MASK_COLOR;
+  PNG_COLOR_TYPE_RGB_ALPHA  = PNG_COLOR_MASK_COLOR or
+                              PNG_COLOR_MASK_ALPHA;
+  PNG_COLOR_TYPE_GRAY_ALPHA = PNG_COLOR_MASK_ALPHA;
+
+// This is for compression type. PNG 1.0 only defines the single type.
+
+  PNG_COMPRESSION_TYPE_BASE    = 0;   // Deflate method 8, 32K window
+  PNG_COMPRESSION_TYPE_DEFAULT = PNG_COMPRESSION_TYPE_BASE;
+
+// This is for filter type. PNG 1.0 only defines the single type.
+
+  PNG_FILTER_TYPE_BASE    = 0;       // Single row per-byte filtering
+  PNG_FILTER_TYPE_DEFAULT = PNG_FILTER_TYPE_BASE;
+
+// These are for the interlacing type.  These values should NOT be changed.
+
+  PNG_INTERLACE_NONE  = 0;      // Non-interlaced image
+  PNG_INTERLACE_ADAM7 = 1;      // Adam7 interlacing
+
+// These are for the oFFs chunk.  These values should NOT be changed.
+
+  PNG_OFFSET_PIXEL      = 0;    // Offset in pixels
+  PNG_OFFSET_MICROMETER = 1;    // Offset in micrometers (1/10^6 meter)
+
+// These are for the pCAL chunk.  These values should NOT be changed.
+
+  PNG_EQUATION_LINEAR     = 0;  // Linear transformation
+  PNG_EQUATION_BASE_E     = 1;  // Exponential base e transform
+  PNG_EQUATION_ARBITRARY  = 2;  // Arbitrary base exponential transform
+  PNG_EQUATION_HYPERBOLIC = 3;  // Hyperbolic sine transformation
+
+// These are for the pHYs chunk.  These values should NOT be changed.
+
+  PNG_RESOLUTION_UNKNOWN = 0;   // pixels/unknown unit (aspect ratio)
+  PNG_RESOLUTION_METER   = 1;   // pixels/meter
+
+// These are for the sRGB chunk.  These values should NOT be changed.
+  PNG_sRGB_INTENT_SATURATION = 0;
+  PNG_sRGB_INTENT_PERCEPTUAL = 1;
+  PNG_sRGB_INTENT_ABSOLUTE   = 2;
+  PNG_sRGB_INTENT_RELATIVE   = 3;
+
+// Handle alpha and tRNS by replacing with a background color.
+  PNG_BACKGROUND_GAMMA_UNKNOWN = 0;
+  PNG_BACKGROUND_GAMMA_SCREEN  = 1;
+  PNG_BACKGROUND_GAMMA_FILE    = 2;
+  PNG_BACKGROUND_GAMMA_UNIQUE  = 3;
+
+// Values for png_set_crc_action() to say how to handle CRC errors in
+// ancillary and critical chunks, and whether to use the data contained
+// therein.  Note that it is impossible to "discard" data in a critical
+// chunk.  For versions prior to 0.90, the action was always error/quit,
+// whereas in version 0.90 and later, the action for CRC errors in ancillary
+// chunks is warn/discard.  These values should NOT be changed.
+
+//      value                   action:critical     action:ancillary
+
+  PNG_CRC_DEFAULT      = 0;  // error/quit          warn/discard data
+  PNG_CRC_ERROR_QUIT   = 1;  // error/quit          error/quit
+  PNG_CRC_WARN_DISCARD = 2;  // (INVALID)           warn/discard data
+  PNG_CRC_WARN_USE     = 3;  // warn/use data       warn/use data
+  PNG_CRC_QUIET_USE    = 4;  // quiet/use data      quiet/use data
+  PNG_CRC_NO_CHANGE    = 5;  // use current value   use current value 
+
+// Flags for png_set_filter() to say which filters to use.  The flags
+// are chosen so that they don't conflict with real filter types
+// below, in case they are supplied instead of the #defined constants.
+// These values should NOT be changed.
+
+  PNG_NO_FILTERS   = $00;
+  PNG_FILTER_NONE  = $08;
+  PNG_FILTER_SUB   = $10;
+  PNG_FILTER_UP    = $20;
+  PNG_FILTER_AVG   = $40;
+  PNG_FILTER_PAETH = $80;
+  PNG_ALL_FILTERS  = PNG_FILTER_NONE or PNG_FILTER_SUB or
+                     PNG_FILTER_UP   or PNG_FILTER_AVG or
+                     PNG_FILTER_PAETH;
+
+// Filter values (not flags) - used in pngwrite.c, pngwutil.c for now.
+// These defines should NOT be changed.
+
+  PNG_FILTER_VALUE_NONE  = 0;
+  PNG_FILTER_VALUE_SUB   = 1;
+  PNG_FILTER_VALUE_UP    = 2;
+  PNG_FILTER_VALUE_AVG   = 3;
+  PNG_FILTER_VALUE_PAETH = 4;
+
+// Heuristic used for row filter selection.  These defines should NOT be
+// changed.
+
+  PNG_FILTER_HEURISTIC_DEFAULT    = 0;  // Currently "UNWEIGHTED"
+  PNG_FILTER_HEURISTIC_UNWEIGHTED = 1;  // Used by libpng < 0.95
+  PNG_FILTER_HEURISTIC_WEIGHTED   = 2;  // Experimental feature
+  PNG_FILTER_HEURISTIC_LAST       = 3;  // Not a valid value 
+
+procedure png_build_grayscale_palette(bit_depth: int; palette: png_colorp);
+             stdcall;
+function png_check_sig(sig: png_bytep; num: int): int;
+             stdcall;
+procedure png_chunk_error(png_ptr: png_structp;
+             const mess: png_charp);
+             stdcall;
+procedure png_chunk_warning(png_ptr: png_structp;
+             const mess: png_charp);
+             stdcall;
+procedure png_convert_from_time_t(ptime: png_timep; ttime: time_t);
+             stdcall;
+function png_convert_to_rfc1123(png_ptr: png_structp; ptime: png_timep):
+             png_charp;
+             stdcall;
+function png_create_info_struct(png_ptr: png_structp): png_infop;
+             stdcall;
+function png_create_read_struct(user_png_ver: png_charp;
+             error_ptr: user_error_ptr; error_fn: png_error_ptr;
+             warn_fn: png_error_ptr): png_structp;
+             stdcall;
+function png_get_copyright(png_ptr: png_structp): png_charp;
+             stdcall;
+function png_get_header_version(png_ptr: png_structp): png_charp;
+             stdcall;
+function png_create_write_struct(user_png_ver: png_charp;
+             error_ptr: user_error_ptr; error_fn: png_error_ptr;
+             warn_fn: png_error_ptr): png_structp;
+             stdcall;
+procedure png_destroy_info_struct(png_ptr: png_structp;
+             info_ptr_ptr: png_infopp);
+             stdcall;
+procedure png_destroy_read_struct(png_ptr_ptr: png_structpp;
+             info_ptr_ptr, end_info_ptr_ptr: png_infopp);
+             stdcall;
+procedure png_destroy_write_struct(png_ptr_ptr: png_structpp;
+             info_ptr_ptr: png_infopp);
+             stdcall;
+function png_get_IHDR(png_ptr: png_structp; info_ptr: png_infop;
+             var width, height: png_uint_32; var bit_depth,
+             color_type, interlace_type, compression_type,
+             filter_type: int): png_uint_32;
+             stdcall;
+function png_get_PLTE(png_ptr: png_structp; info_ptr: png_infop;
+             var palette: png_colorp; var num_palette: int):
+             png_uint_32;
+             stdcall;
+function png_get_bKGD(png_ptr: png_structp; info_ptr: png_infop;
+             var background: png_color_16p): png_uint_32;
+             stdcall;
+function png_get_bit_depth(png_ptr: png_structp; info_ptr: png_infop):
+             png_byte;
+             stdcall;
+function png_get_cHRM(png_ptr: png_structp; info_ptr: png_infop;
+             var white_x, white_y, red_x, red_y, green_x, green_y,
+             blue_x, blue_y: double): png_uint_32;
+             stdcall;
+function png_get_channels(png_ptr: png_structp; info_ptr: png_infop):
+             png_byte;
+             stdcall;
+function png_get_color_type(png_ptr: png_structp; info_ptr: png_infop):
+             png_byte;
+             stdcall;
+function png_get_compression_type(png_ptr: png_structp;
+             info_ptr: png_infop): png_byte;
+             stdcall;
+function png_get_error_ptr(png_ptr: png_structp): png_voidp;
+             stdcall;
+function png_get_filter_type(png_ptr: png_structp; info_ptr: png_infop):
+             png_byte;
+             stdcall;
+function png_get_gAMA(png_ptr: png_structp; info_ptr: png_infop;
+             var file_gamma: double): png_uint_32;
+             stdcall;
+function png_get_hIST(png_ptr: png_structp; info_ptr: png_infop;
+             var hist: png_uint_16p): png_uint_32;
+             stdcall;
+function png_get_image_height(png_ptr: png_structp; info_ptr: png_infop):
+             png_uint_32;
+             stdcall;
+function png_get_image_width(png_ptr: png_structp; info_ptr: png_infop):
+             png_uint_32;
+             stdcall;
+function png_get_interlace_type(png_ptr: png_structp;
+             info_ptr: png_infop): png_byte;
+             stdcall;
+function png_get_io_ptr(png_ptr: png_structp): png_voidp;
+             stdcall;
+function png_get_oFFs(png_ptr: png_structp; info_ptr: png_infop;
+             var offset_x, offset_y: png_uint_32;
+             var unit_type: int): png_uint_32;
+             stdcall;
+function png_get_pCAL(png_ptr: png_structp; info_ptr: png_infop;
+             var purpose: png_charp; var X0, X1: png_int_32;
+             var typ, nparams: int; var units: png_charp;
+             var params: png_charpp): png_uint_32;
+             stdcall;
+function png_get_pHYs(png_ptr: png_structp; info_ptr: png_infop;
+             var res_x, res_y: png_uint_32; var unit_type: int):
+             png_uint_32;
+             stdcall;
+function png_get_pixel_aspect_ratio(png_ptr: png_structp;
+             info_ptr: png_infop): float;
+             stdcall;
+function png_get_pixels_per_meter(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+function png_get_progressive_ptr(png_ptr: png_structp): png_voidp;
+             stdcall;
+function png_get_rgb_to_gray_status(png_ptr: png_structp);
+             stdcall;
+function png_get_rowbytes(png_ptr: png_structp; info_ptr: png_infop):
+             png_uint_32;
+             stdcall;
+function png_get_sBIT(png_ptr: png_structp; info_ptr: png_infop;
+             var sig_bits: png_color_8p): png_uint_32;
+             stdcall;
+function png_get_sRGB(png_ptr: png_structp; info_ptr: png_infop;
+             var file_srgb_intent: int): png_uint_32;
+             stdcall; 
+function png_get_signature(png_ptr: png_structp; info_ptr: png_infop):
+             png_bytep;
+             stdcall;
+function png_get_tIME(png_ptr: png_structp; info_ptr: png_infop;
+             var mod_time: png_timep): png_uint_32;
+             stdcall;
+function png_get_tRNS(png_ptr: png_structp; info_ptr: png_infop;
+             var trans: png_bytep; var num_trans: int;
+             var trans_values: png_color_16p): png_uint_32;
+             stdcall;
+function png_get_text(png_ptr: png_structp; info_ptr: png_infop;
+             var text_ptr: png_textp; var num_text: int):
+             png_uint_32;
+             stdcall;
+function png_get_valid(png_ptr: png_structp; info_ptr: png_infop;
+             flag: png_uint_32): png_uint_32;
+             stdcall;
+function png_get_x_offset_microns(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+function png_get_x_offset_pixels(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+function png_get_x_pixels_per_meter(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+function png_get_y_offset_microns(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+function png_get_y_offset_pixels(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+function png_get_y_pixels_per_meter(png_ptr: png_structp;
+             info_ptr: png_infop): png_uint_32;
+             stdcall;
+procedure png_process_data(png_ptr: png_structp; info_ptr: png_infop;
+             buffer: png_bytep; buffer_size: png_size_t);
+             stdcall;
+procedure png_progressive_combine_row(png_ptr: png_structp;
+             old_row, new_row: png_bytep);
+             stdcall;
+procedure png_read_end(png_ptr: png_structp; info_ptr: png_infop);
+              stdcall;
+procedure png_read_image(png_ptr: png_structp; image: png_bytepp);
+             stdcall;
+procedure png_read_info(png_ptr: png_structp; info_ptr: png_infop);
+             stdcall;
+procedure png_read_row(png_ptr: png_structp; row, dsp_row: png_bytep);
+             stdcall;
+procedure png_read_rows(png_ptr: png_structp; row, display_row:
+              png_bytepp; num_rows: png_uint_32);
+             stdcall;
+procedure png_read_update_info(png_ptr: png_structp; info_ptr: png_infop);
+             stdcall;
+procedure png_set_IHDR(png_ptr: png_structp; info_ptr: png_infop;
+             width, height: png_uint_32; bit_depth, color_type,
+             interlace_type, compression_type, filter_type: int);
+             stdcall;
+procedure png_set_PLTE(png_ptr: png_structp; info_ptr: png_infop;
+             palette: png_colorp; num_palette: int);
+             stdcall;
+procedure png_set_bKGD(png_ptr: png_structp; info_ptr: png_infop;
+             background: png_color_16p);
+             stdcall;
+procedure png_set_background(png_ptr: png_structp;
+             background_color: png_color_16p;
+             background_gamma_code, need_expand: int;
+             background_gamma: double);
+             stdcall;
+procedure png_set_bgr(png_ptr: png_structp);
+             stdcall;
+procedure png_set_cHRM(png_ptr: png_structp; info_ptr: png_infop;
+             white_x, white_y, red_x, red_y, green_x, green_y,
+             blue_x, blue_y: double);
+             stdcall;
+procedure png_set_compression_level(png_ptr: png_structp; level: int);
+             stdcall;
+procedure png_set_compression_mem_level(png_ptr: png_structp;
+             mem_level: int);
+             stdcall;
+procedure png_set_compression_method(png_ptr: png_structp; method: int);
+             stdcall;
+procedure png_set_compression_strategy(png_ptr: png_structp;
+             strategy: int);
+             stdcall;
+procedure png_set_compression_window_bits(png_ptr: png_structp;
+             window_bits: int);
+             stdcall;
+procedure png_set_crc_action(png_ptr: png_structp;
+             crit_action, ancil_action: int);
+             stdcall;
+procedure png_set_dither(png_ptr: png_structp; plaette: png_colorp;
+             num_palette, maximum_colors: int;
+             histogram: png_uint_16p; full_dither: int);
+             stdcall;
+procedure png_set_error_fn(png_ptr: png_structp; error_ptr: png_voidp;
+             error_fn, warning_fn: png_error_ptr);
+             stdcall;
+procedure png_set_expand(png_ptr: png_structp);
+             stdcall;
+procedure png_set_filler(png_ptr: png_structp; filler: png_uint_32;
+             filler_loc: int);
+             stdcall;
+procedure png_set_filter(png_ptr: png_structp; method, filters: int);
+             stdcall;
+procedure png_set_filter_heuristics(png_ptr: png_structp;
+             heuristic_method, num_weights: int;
+             filter_weights, filter_costs: png_doublep);
+             stdcall;
+procedure png_set_flush(png_ptr: png_structp; nrows: int);
+             stdcall;
+procedure png_set_gAMA(png_ptr: png_structp; info_ptr: png_infop;
+             file_gamma: double);
+             stdcall;
+procedure png_set_gamma(png_ptr: png_structp; screen_gamma,
+             default_file_gamma: double);
+             stdcall;
+procedure png_set_gray_1_2_4_to_8(png_ptr: png_structp);
+             stdcall;
+procedure png_set_gray_to_rgb(png_ptr: png_structp);
+             stdcall;
+procedure png_set_hIST(png_ptr: png_structp; info_ptr: png_infop;
+             hist: png_uint_16p);
+             stdcall;
+function png_set_interlace_handling(png_ptr: png_structp): int;
+             stdcall;
+procedure png_set_invert_alpha(png_ptr: png_structp);
+             stdcall;
+procedure png_set_invert_mono(png_ptr: png_structp);
+             stdcall;
+procedure png_set_oFFs(png_ptr: png_structp; info_ptr: png_infop;
+             offset_x, offset_y: png_uint_32; unit_type: int);
+             stdcall;
+procedure png_set_palette_to_rgb(png_ptr: png_structp);
+             stdcall;
+procedure png_set_pCAL(png_ptr: png_structp; info_ptr: png_infop;
+             purpose: png_charp; X0, X1: png_int_32;
+             typ, nparams: int; units: png_charp;
+             params: png_charpp);
+             stdcall;
+procedure png_set_pHYs(png_ptr: png_structp; info_ptr: png_infop;
+             res_x, res_y: png_uint_32; unit_type: int);
+             stdcall;
+procedure png_set_packing(png_ptr: png_structp);
+             stdcall;
+procedure png_set_packswap(png_ptr: png_structp);
+             stdcall;
+procedure png_set_progressive_read_fn(png_ptr: png_structp;
+             progressive_ptr: png_voidp;
+             info_fn: png_progressive_info_ptr;
+             row_fn: png_progressive_row_ptr;
+             end_fn: png_progressive_end_ptr);
+             stdcall;
+procedure png_set_read_fn(png_ptr: png_structp;
+             io_ptr: png_voidp; read_data_fn: png_rw_ptr);
+             stdcall;
+procedure png_set_read_status_fn(png_ptr: png_structp;
+             read_row_fn: png_read_status_ptr);
+             stdcall;
+procedure png_set_read_user_transform_fn(png_ptr: png_structp;
+             read_user_transform_fn: png_user_transform_ptr);
+             stdcall;
+procedure png_set_rgb_to_gray(png_ptr: png_structp; int: error_action);
+             stdcall;
+procedure png_set_sBIT(png_ptr: png_structp; info_ptr: png_infop;
+             sig_bits: png_color_8p);
+             stdcall;
+procedure png_set_sRGB(png_ptr: png_structp; info_ptr: png_infop;
+             intent: int);
+             stdcall;
+procedure png_set_sRGB_gAMA_and_cHRM(png_ptr: png_structp;
+             info_ptr: png_infop; intent: int);
+             stdcall;
+procedure png_set_shift(png_ptr: png_structp; true_bits: png_color_8p);
+             stdcall;
+procedure png_set_sig_bytes(png_ptr: png_structp; num_bytes: int);
+             stdcall;
+procedure png_set_strip_16(png_ptr: png_structp);
+             stdcall;
+procedure png_set_strip_alpha(png_ptr: png_structp);
+             stdcall;
+procedure png_set_swap(png_ptr: png_structp);
+             stdcall;
+procedure png_set_swap_alpha(png_ptr: png_structp);
+             stdcall;
+procedure png_set_tIME(png_ptr: png_structp; info_ptr: png_infop;
+             mod_time: png_timep);
+             stdcall;
+procedure png_set_tRNS(png_ptr: png_structp; info_ptr: png_infop;
+             trans: png_bytep; num_trans: int;
+             trans_values: png_color_16p);
+             stdcall;
+procedure png_set_tRNS_to_alpha(png_ptr: png_structp);
+             stdcall;
+procedure png_set_text(png_ptr: png_structp; info_ptr: png_infop;
+             text_ptr: png_textp; num_text: int);
+             stdcall;
+procedure png_set_write_fn(png_ptr: png_structp;
+             io_ptr: png_voidp; write_data_fn: png_rw_ptr;
+             output_flush_fn: png_flush_ptr);
+             stdcall;
+procedure png_set_write_status_fn(png_ptr: png_structp;
+             write_row_fn: png_write_status_ptr);
+             stdcall;
+procedure png_set_write_user_transform_fn(png_ptr: png_structp;
+             write_user_transform_fn: png_user_transform_ptr);
+             stdcall;
+function png_sig_cmp(sig: png_bytep; start, num_to_check: png_size_t):
+             int;
+             stdcall;
+procedure png_start_read_image(png_ptr: png_structp);
+             stdcall;
+procedure png_write_chunk(png_ptr: png_structp;
+             chunk_name, data: png_bytep; length: png_size_t);
+             stdcall;
+procedure png_write_chunk_data(png_ptr: png_structp;
+             data: png_bytep; length: png_size_t);
+             stdcall;
+procedure png_write_chunk_end(png_ptr: png_structp);
+             stdcall;
+procedure png_write_chunk_start(png_ptr: png_structp;
+             chunk_name: png_bytep; length: png_uint_32);
+             stdcall;
+procedure png_write_end(png_ptr: png_structp; info_ptr: png_infop);
+             stdcall;
+procedure png_write_flush(png_ptr: png_structp);
+             stdcall;
+procedure png_write_image(png_ptr: png_structp; image: png_bytepp);
+             stdcall;
+procedure png_write_info(png_ptr: png_structp; info_ptr: png_infop);
+             stdcall;
+procedure png_write_row(png_ptr: png_structp; row: png_bytep);
+             stdcall;
+procedure png_write_rows(png_ptr: png_structp; row: png_bytepp;
+             num_rows: png_uint_32);
+             stdcall;
+
+implementation
+
+const
+  pngDLL = 'png32bd.dll';
+
+procedure png_build_grayscale_palette; external pngDLL;
+function png_check_sig; external pngDLL;
+procedure png_chunk_error; external pngDLL;
+procedure png_chunk_warning; external pngDLL;
+procedure png_convert_from_time_t; external pngDLL;
+function png_convert_to_rfc1123; external pngDLL;
+function png_create_info_struct; external pngDLL;
+function png_create_read_struct; external pngDLL;
+function png_create_write_struct; external pngDLL;
+procedure png_destroy_info_struct; external pngDLL;
+procedure png_destroy_read_struct; external pngDLL;
+procedure png_destroy_write_struct; external pngDLL;
+function png_get_IHDR; external pngDLL;
+function png_get_PLTE; external pngDLL;
+function png_get_bKGD; external pngDLL;
+function png_get_bit_depth; external pngDLL;
+function png_get_cHRM; external pngDLL;
+function png_get_channels; external pngDLL;
+function png_get_color_type; external pngDLL;
+function png_get_compression_type; external pngDLL;
+function png_get_error_ptr; external pngDLL;
+function png_get_filter_type; external pngDLL;
+function png_get_gAMA; external pngDLL;
+function png_get_hIST; external pngDLL;
+function png_get_image_height; external pngDLL;
+function png_get_image_width; external pngDLL;
+function png_get_interlace_type; external pngDLL;
+function png_get_io_ptr; external pngDLL;
+function png_get_oFFs; external pngDLL;
+function png_get_pCAL; external pngDLL;
+function png_get_pHYs; external pngDLL;
+function png_get_pixel_aspect_ratio; external pngDLL;
+function png_get_pixels_per_meter; external pngDLL;
+function png_get_progressive_ptr; external pngDLL;
+function png_get_rowbytes; external pngDLL;
+function png_get_sBIT; external pngDLL;
+function png_get_sRGB; external pngDLL;
+function png_get_signature; external pngDLL;
+function png_get_tIME; external pngDLL;
+function png_get_tRNS; external pngDLL;
+function png_get_text; external pngDLL;
+function png_get_valid; external pngDLL;
+function png_get_x_offset_microns; external pngDLL;
+function png_get_x_offset_pixels; external pngDLL;
+function png_get_x_pixels_per_meter; external pngDLL;
+function png_get_y_offset_microns; external pngDLL;
+function png_get_y_offset_pixels; external pngDLL;
+function png_get_y_pixels_per_meter; external pngDLL;
+procedure png_process_data; external pngDLL;
+procedure png_progressive_combine_row; external pngDLL;
+procedure png_read_end; external pngDLL;
+procedure png_read_image; external pngDLL;
+procedure png_read_info; external pngDLL;
+procedure png_read_row; external pngDLL;
+procedure png_read_rows; external pngDLL;
+procedure png_read_update_info; external pngDLL;
+procedure png_set_IHDR; external pngDLL;
+procedure png_set_PLTE; external pngDLL;
+procedure png_set_bKGD; external pngDLL;
+procedure png_set_background; external pngDLL;
+procedure png_set_bgr; external pngDLL;
+procedure png_set_cHRM; external pngDLL;
+procedure png_set_compression_level; external pngDLL;
+procedure png_set_compression_mem_level; external pngDLL;
+procedure png_set_compression_method; external pngDLL;
+procedure png_set_compression_strategy; external pngDLL;
+procedure png_set_compression_window_bits; external pngDLL;
+procedure png_set_crc_action; external pngDLL;
+procedure png_set_dither; external pngDLL;
+procedure png_set_error_fn; external pngDLL;
+procedure png_set_expand; external pngDLL;
+procedure png_set_filler; external pngDLL;
+procedure png_set_filter; external pngDLL;
+procedure png_set_filter_heuristics; external pngDLL;
+procedure png_set_flush; external pngDLL;
+procedure png_set_gAMA; external pngDLL;
+procedure png_set_gamma; external pngDLL;
+procedure png_set_gray_to_rgb; external pngDLL;
+procedure png_set_hIST; external pngDLL;
+function png_set_interlace_handling; external pngDLL;
+procedure png_set_invert_alpha; external pngDLL;
+procedure png_set_invert_mono; external pngDLL;
+procedure png_set_oFFs; external pngDLL;
+procedure png_set_pCAL; external pngDLL;
+procedure png_set_pHYs; external pngDLL;
+procedure png_set_packing; external pngDLL;
+procedure png_set_packswap; external pngDLL;
+procedure png_set_progressive_read_fn; external pngDLL;
+procedure png_set_read_fn; external pngDLL;
+procedure png_set_read_status_fn; external pngDLL;
+procedure png_set_read_user_transform_fn; external pngDLL;
+procedure png_set_sBIT; external pngDLL;
+procedure png_set_sRGB; external pngDLL;
+procedure png_set_sRGB_gAMA_and_cHRM; external pngDLL;
+procedure png_set_shift; external pngDLL;
+procedure png_set_sig_bytes; external pngDLL;
+procedure png_set_strip_16; external pngDLL;
+procedure png_set_strip_alpha; external pngDLL;
+procedure png_set_swap; external pngDLL;
+procedure png_set_swap_alpha; external pngDLL;
+procedure png_set_tIME; external pngDLL;
+procedure png_set_tRNS; external pngDLL;
+procedure png_set_text; external pngDLL;
+procedure png_set_write_fn; external pngDLL;
+procedure png_set_write_status_fn; external pngDLL;
+procedure png_set_write_user_transform_fn; external pngDLL;
+function png_sig_cmp; external pngDLL;
+procedure png_start_read_image; external pngDLL;
+procedure png_write_chunk; external pngDLL;
+procedure png_write_chunk_data; external pngDLL;
+procedure png_write_chunk_end; external pngDLL;
+procedure png_write_chunk_start; external pngDLL;
+procedure png_write_end; external pngDLL;
+procedure png_write_flush; external pngDLL;
+procedure png_write_image; external pngDLL;
+procedure png_write_info; external pngDLL;
+procedure png_write_row; external pngDLL;
+procedure png_write_rows; external pngDLL;
+
+end.

scripts/pngdll.mak

@@ -0,0 +1,53 @@
+# Makefile for png32bd.dll
+# ------------- Borland C++ 4.5 -------------
+
+# This makefile expects to find zlib.h and zlib32bd.lib in the
+# $(ZLIBDIR) directory.
+
+# The object files here are compiled with the "stdcall" calling convention.
+# This DLL requires zlib32bd.lib to be compiled in the same way.
+
+# Note that png32bd.dll exports the zlib functions adler32, crc32 and
+# the deflate... and inflate... functions. It does not export the
+# compress and uncompress functions, nor any of the gz... functions,
+# since libpng does not call them.
+
+ZLIBDIR=..\zlib112
+ZLIB=zlib32bd.lib
+PNGDLL=png32bd.dll
+
+CFLAGS= -ps -O2 -C -K -N- -k- -d -3 -r- -w-par -w-aus -WDE -I$(ZLIBDIR)
+CC=f:\bc45\bin\bcc32
+LINKFLAGS= -Tpd -aa -c
+LINK=f:\bc45\bin\tlink32
+LIBDIR=f:\bc45\lib
+IMPLIB=f:\bc45\bin\implib
+
+.autodepend
+.c.obj:
+        $(CC) -c $(CFLAGS) $<
+ 
+OBJ1=png.obj pngerror.obj pngget.obj pngmem.obj pngpread.obj 
+OBJ2=pngread.obj pngrio.obj pngrtran.obj pngrutil.obj pngset.obj 
+OBJ3=pngtrans.obj pngwio.obj pngwrite.obj pngwtran.obj pngwutil.obj
+
+all: $(PNGDLL)
+
+$(PNGDLL): $(OBJ1) $(OBJ2) $(OBJ3) $(ZLIBDIR)\$(ZLIB)
+        $(LINK) @&&|
+$(LINKFLAGS) $(LIBDIR)\c0d32 +
+$(OBJ1) +
+$(OBJ2) +
+$(OBJ3)
+$@
+-x
+$(ZLIBDIR)\$(ZLIB) $(LIBDIR)\import32 $(LIBDIR)\cw32
+|,&&|
+LIBRARY $(@B)
+EXETYPE WINDOWS
+CODE PRELOAD MOVEABLE DISCARDABLE
+DATA PRELOAD MOVEABLE MULTIPLE
+|
+        $(IMPLIB) -c $(@R).lib $@
+
+# End of makefile for png32bd.dll

scripts/pngos2.def

@@ -0,0 +1,296 @@
+;----------------------------------------
+; PNGLIB module definition file for OS/2
+;----------------------------------------
+
+LIBRARY		PNG
+DESCRIPTION	"PNG image compression library for OS/2"
+CODE		PRELOAD MOVEABLE DISCARDABLE
+DATA		PRELOAD MOVEABLE MULTIPLE
+
+EXPORTS
+  png_set_sig_bytes
+  png_sig_cmp
+  png_check_sig
+  png_create_read_struct
+; png_create_read_struct_2
+  png_create_write_struct
+; png_create_write_struct_2
+  png_write_chunk
+  png_write_chunk_start
+  png_write_chunk_data
+  png_write_chunk_end
+  png_create_info_struct
+  png_info_init
+  png_write_info
+  png_read_info
+  png_convert_to_rfc1123
+  png_convert_from_struct_tm
+  png_convert_from_time_t
+  png_set_expand
+  png_set_bgr
+  png_set_gray_to_rgb
+  png_set_rgb_to_gray
+  png_build_grayscale_palette
+  png_set_strip_alpha
+  png_set_swap_alpha
+  png_set_invert_alpha
+  png_set_filler
+  png_set_swap
+  png_set_packing
+  png_set_packswap
+  png_set_shift
+  png_set_interlace_handling
+  png_set_invert_mono
+  png_set_background
+  png_set_strip_16
+  png_set_dither
+  png_set_gamma
+  png_set_flush
+  png_write_flush
+  png_start_read_image
+  png_read_update_info
+  png_read_rows
+  png_read_row
+  png_read_image
+  png_write_row
+  png_write_rows
+  png_write_image
+  png_write_end
+  png_read_end
+  png_destroy_info_struct
+  png_destroy_read_struct
+  png_read_destroy
+  png_destroy_write_struct
+; png_write_destroy_info
+  png_write_destroy
+  png_set_crc_action
+  png_set_filter
+  png_set_filter_heuristics
+  png_set_compression_level
+  png_set_compression_mem_level
+  png_set_compression_strategy
+  png_set_compression_window_bits
+  png_set_compression_method
+  png_init_io
+  png_get_copyright
+  png_set_error_fn
+  png_get_error_ptr
+  png_get_header_version
+; png_get_mem_fn
+; png_set_mem_fn
+  png_set_write_fn
+  png_set_read_fn
+  png_set_write_status_fn
+  png_set_read_status_fn
+  png_get_io_ptr
+  png_set_progressive_read_fn
+  png_set_read_status_fn
+  png_set_read_user_transform_fn
+  png_set_write_status_fn
+  png_set_write_user_transform_fn
+  png_get_progressive_ptr
+  png_process_data
+  png_progressive_combine_row
+  png_malloc
+  png_free
+  png_memcpy_check
+  png_memset_check
+; png_malloc_default
+; png_free_default
+; png_far_to_near
+  png_error
+  png_chunk_error
+  png_warning
+  png_chunk_warning
+  png_get_valid
+  png_get_rowbytes
+  png_get_channels
+  png_get_image_width
+  png_get_image_height
+  png_get_bit_depth
+  png_get_color_type
+  png_get_filter_type
+  png_get_interlace_type
+  png_get_compression_type
+  png_get_pixels_per_meter
+  png_get_pixel_aspect_ratio
+  png_get_rgb_to_gray_status
+  png_get_x_offset_pixels
+  png_get_y_offset_pixels
+  png_get_x_offset_microns
+  png_get_y_offset_microns
+  png_get_signature
+  png_get_bKGD
+  png_set_bKGD
+  png_get_cHRM
+  png_set_cHRM
+  png_get_gAMA
+  png_set_gAMA
+  png_get_hIST
+  png_set_hIST
+  png_get_IHDR
+  png_set_IHDR
+  png_get_oFFs
+  png_set_oFFs
+  png_get_pCAL
+  png_set_pCAL
+  png_get_pHYs
+  png_set_pHYs
+  png_get_PLTE
+  png_set_PLTE
+  png_get_sBIT
+  png_set_sBIT
+  png_get_sRGB
+  png_set_sRGB
+  png_set_sRGB_gAMA_and_cHRM
+  png_get_text
+  png_set_text
+  png_get_tIME
+  png_set_tIME
+  png_get_tRNS
+  png_set_tRNS
+  png_set_gray_1_2_4_to_8
+  png_set_tRNS_to_alpha
+  png_set_palette_to_rgb
+
+  png_create_struct
+  png_destroy_struct
+  png_info_destroy
+  png_zalloc
+  png_zfree
+  png_reset_crc
+  png_write_data
+  png_read_data
+  png_crc_read
+  png_crc_finish
+  png_crc_error
+  png_calculate_crc
+  png_flush
+  png_save_uint_32
+  png_save_int_32
+  png_save_uint_16
+  png_write_sig
+  png_write_IHDR
+  png_write_PLTE
+  png_write_IDAT
+  png_write_IEND
+  png_write_gAMA
+  png_write_sBIT
+  png_write_cHRM
+  png_write_sRGB
+  png_write_tRNS
+  png_write_bKGD
+  png_write_hIST
+  png_check_keyword
+  png_write_tEXt
+  png_write_zTXt
+  png_write_oFFs
+  png_write_pCAL
+  png_write_pHYs
+  png_write_tIME
+  png_write_finish_row
+  png_write_start_row
+  png_build_gamma_table
+  png_combine_row
+  png_do_read_interlace
+  png_do_write_interlace
+  png_read_filter_row
+  png_write_find_filter
+  png_write_filtered_row
+  png_read_finish_row
+  png_read_start_row
+  png_read_transform_info
+  png_do_read_filler
+  png_do_read_swap_alpha
+  png_do_write_swap_alpha
+  png_do_read_invert_alpha
+  png_do_write_invert_alpha
+  png_do_strip_filler
+  png_do_swap
+  png_do_packswap
+  png_do_rgb_to_gray
+  png_do_gray_to_rgb
+  png_do_unpack
+  png_do_unshift
+  png_do_invert
+  png_do_chop
+  png_do_dither
+; png_correct_palette
+  png_do_bgr
+  png_do_pack
+  png_do_shift
+  png_do_background
+  png_do_gamma
+  png_do_expand_palette
+  png_do_expand
+  png_handle_IHDR
+  png_handle_PLTE
+  png_handle_IEND
+  png_handle_gAMA
+  png_handle_sBIT
+  png_handle_cHRM
+  png_handle_sRGB
+  png_handle_tRNS
+  png_handle_bKGD
+  png_handle_hIST
+  png_handle_oFFs
+  png_handle_pCAL
+  png_handle_pHYs
+  png_handle_tIME
+  png_handle_tEXt
+  png_handle_zTXt
+  png_handle_unknown
+  png_check_chunk_name
+  png_do_read_transformations
+  png_do_write_transformations
+  png_init_read_transformations
+  png_push_read_chunk
+  png_push_read_sig
+; png_push_check_crc
+  png_push_crc_skip
+  png_push_crc_finish
+  png_push_fill_buffer
+  png_push_save_buffer
+  png_push_restore_buffer
+  png_push_read_IDAT
+  png_process_IDAT_data
+  png_push_process_row
+  png_push_handle_unknown
+  png_push_have_info
+  png_push_have_end
+  png_push_have_row
+; png_push_read_end
+  png_process_some_data
+  png_read_push_finish_row
+  png_push_handle_tEXt
+  png_push_read_tEXt
+  png_push_handle_zTXt
+  png_push_read_zTXt
+
+  png_libpng_ver
+  png_pass_start
+  png_pass_inc
+  png_pass_ystart
+  png_pass_yinc
+  png_pass_mask
+  png_pass_dsp_mask
+; png_pass_width
+; png_pass_height
+
+  png_IHDR
+  png_IDAT
+  png_IEND
+  png_PLTE
+  png_bKGD
+  png_cHRM
+  png_gAMA
+  png_hIST
+  png_oFFs
+  png_pCAL
+  png_pHYs
+  png_sBIT
+  png_sRGB
+  png_tEXt
+  png_tIME
+  png_tRNS
+  png_zTXt

scripts/smakefile.ppc

@@ -0,0 +1,29 @@
+# Amiga powerUP (TM) Makefile
+# makefile for libpng and SAS C V6.58/7.00 PPC compiler
+# Copyright (C) 1998 by Andreas R. Kleinert
+
+CC       = scppc
+CFLAGS   = NOSTKCHK NOSINT OPTIMIZE OPTGO OPTPEEP OPTINLOCAL OPTINL IDIR /zlib \
+           OPTLOOP OPTRDEP=8 OPTDEP=8 OPTCOMP=8
+LIBNAME  = libpng.a
+AR       = ppc-amigaos-ar
+AR_FLAGS = cr
+RANLIB   = ppc-amigaos-ranlib
+LDFLAGS  = -r -o
+LDLIBS   =  ../zlib/libzip.a LIB:scppc.a
+LN       = ppc-amigaos-ld
+RM       = delete quiet
+MKDIR    = makedir
+
+OBJS = png.o pngset.o pngget.o pngrutil.o pngtrans.o pngwutil.o pngread.o \
+pngerror.o pngpread.o pngwrite.o pngrtran.o pngwtran.o pngrio.o pngwio.o pngmem.o
+
+all: $(LIBNAME) pngtest
+
+$(LIBNAME): $(OBJS)
+            $(AR) $(AR_FLAGS) $@ $(OBJS)
+            $(RANLIB) $@
+
+pngtest: pngtest.o $(LIBNAME)
+        $(LN) $(LDFLAGS) pngtest LIB:c_ppc.o pngtest.o $(LIBNAME) $(LDLIBS) \
+LIB:end.o