Imported from libpng-1.0.5d.tar

ANNOUNCE

@@ -1,38 +1,48 @@
 
-Libpng 1.0.2a - December 29, 1998
+Libpng 1.0.5d - November 29, 1999
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
 
-Changes since the last public release:
+Changes since the last public release (1.0.5):
 
-libpng-1.0.2a:
-
-  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 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 libpng-1.0.5a October 23, 1999
+  Added contrib/pngsuite and contrib/pngminus (Willem van Schaik)
+  Fixed a typo in the png_set_sRGB() function call in example.c (Jan Nijtmans)
+  Further optimization and bugfix of pngvcrd.c
+  Revised pngset.c so that it does not allocate or free memory in the user's
+    text_ptr structure.  Instead, it makes its own copy.
+  Created separate write_end_info_struct in pngtest.c for a more severe test.
+  Added code in pngwrite.c to free info_ptr->text[i].key to stop a memory leak.
+version libpng-1.0.5b November 23, 1999
+  Moved PNG_FLAG_HAVE_CHUNK_HEADER, PNG_FLAG_BACKGROUND_IS_GRAY and
+    PNG_FLAG_WROTE_tIME from flags to mode.
+  Added png_write_info_before_PLTE() function.
+  Fixed some typecasting in contrib/gregbook/*.c
+  Updated scripts/makevms.com and added makevms.com to contrib/gregbook
+    and contrib/pngminus (Martin Zinser)
+version libpng-1.0.5c November 26, 1999
+  Moved png_get_header_version from png.h to png.c, to accomodate ansi2knr.
+  Removed all global arrays (according to PNG_NO_GLOBAL_ARRAYS macro), to
+    accomodate making DLL's: Moved usr_png_ver from global variable to function
+    png_get_header_ver() in png.c.  Moved png_sig to png_sig_bytes in png.c and
+    eliminated use of png_sig in pngwutil.c.  Moved the various png_CHNK arrays
+    into pngtypes.h.  Eliminated use of global png_pass arrays.  Declared the
+    png_CHNK and png_pass arrays to be "const".  Made the global arrays
+    available to applications (although none are used in libpng itself) when
+    PNG_NO_GLOBAL_ARRAYS is not defined or when PNG_GLOBAL_ARRAYS is defined.
+  Removed some extraneous "-I" from contrib/pngminus/makefile.std
+  Changed the PNG_sRGB_INTENT macros in png.h to be consistent with PNG-1.2.
+  Change PNG_SRGB_INTENT to PNG_sRGB_INTENT in libpng.txt and libpng.3 
+version 1.0.5d [November 29, 1999]
+  Add type cast (png_const_charp) two places in png.c
+  Eliminated pngtypes.h; use macros instead to declare PNG_CHNK arrays.
+  Renamed "PNG_GLOBAL_ARRAYS" to "PNG_USE_GLOBAL_ARRAYS" and made available
+    to applications a macro "PNG_USE_LOCAL_ARRAYS".
+  #ifdef out all the new declarations when PNG_USE_GLOBAL_ARRAYS is defined.
+  Added PNG_EXPORT_VAR macro to accommodate making DLL's.
 
 Send comments/corrections/commendations to
-png-implement@dworkin.wustl.edu or to randeg@alumni.rpi.edu
+png-implement@ccrc.wustl.edu or to randeg@alum.rpi.edu
 
 Glenn R-P

CHANGES

@@ -352,12 +352,14 @@ version 1.0.1e [June 6, 1998]
   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 29, 1998]
+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.
@@ -376,3 +378,136 @@ version 1.0.2a [December 29, 1998]
   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 24, 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.
+  Revised documentation, png.h, and example.c to remove reference to
+    "viewing_gamma" which no longer appears in the PNG specification.
+  Revised pngvcrd.c to use MMX code for interlacing only on the final pass.
+  Updated pngvcrd.c to use the faster C filter algorithms from libpng-1.0.1a
+  Split makefile.win32vc into two versions, makefile.vcawin32 (uses MMX
+    assembler code) and makefile.vcwin32 (doesn't).
+  Added a CPU timing report to pngtest.c (enabled by defining PNGTEST_TIMING)
+  Added a copy of pngnow.png to the distribution.
+version 1.0.4a [September 25, 1999]
+  Increase max_pixel_depth in pngrutil.c if a user transform needs it.
+  Changed several division operations to right-shifts in pngvcrd.c
+version 1.0.4b [September 30, 1999]
+  Added parentheses in line 3732 of pngvcrd.c
+  Added a comment in makefile.linux warning about buggy -O3 in pgcc 2.95.1
+version 1.0.4c [October 1, 1999]
+  Added a "png_check_version" function in png.c and pngtest.c that will generate
+    a helpful compiler error if an old png.h is found in the search path.
+  Changed type of png_user_transform_depth|channels from int to png_byte.
+version 1.0.4d [October 6, 1999]
+  Changed 0.45 to 0.45455 in png_set_sRGB()
+  Removed unused PLTE entries from pngnow.png
+  Re-enabled some parts of pngvcrd.c (png_combine_row) that work properly.
+version 1.0.4e [October 10, 1999]
+  Fixed sign error in pngvcrd.c (Greg Roelofs)
+  Replaced some instances of memcpy with simple assignments in pngvcrd (GR-P)
+version 1.0.4f [October 15, 1999]
+  Surrounded example.c code with #if 0 .. #endif to prevent people from
+    inadvertently trying to compile it.
+  Changed png_get_header_version() from a function to a macro in png.h
+  Added type casting mostly in pngrtran.c and pngwtran.c
+  Removed some pointless "ptr = NULL" in pngmem.c
+  Added a "contrib" directory containing the source code from Greg's book.
+version 1.0.5 [October 15, 1999]
+  Minor editing of the INSTALL and README files.
+version 1.0.5a [October 23, 1999]
+  Added contrib/pngsuite and contrib/pngminus (Willem van Schaik)
+  Fixed a typo in the png_set_sRGB() function call in example.c (Jan Nijtmans)
+  Further optimization and bugfix of pngvcrd.c
+  Revised pngset.c so that it does not allocate or free memory in the user's
+    text_ptr structure.  Instead, it makes its own copy.
+  Created separate write_end_info_struct in pngtest.c for a more severe test.
+  Added code in pngwrite.c to free info_ptr->text[i].key to stop a memory leak.
+version 1.0.5b [November 23, 1999]
+  Moved PNG_FLAG_HAVE_CHUNK_HEADER, PNG_FLAG_BACKGROUND_IS_GRAY and
+    PNG_FLAG_WROTE_tIME from flags to mode.
+  Added png_write_info_before_PLTE() function.
+  Fixed some typecasting in contrib/gregbook/*.c
+  Updated scripts/makevms.com and added makevms.com to contrib/gregbook
+    and contrib/pngminus (Martin Zinser)
+version 1.0.5c [November 26, 1999]
+  Moved png_get_header_version from png.h to png.c, to accomodate ansi2knr.
+  Removed all global arrays (according to PNG_NO_GLOBAL_ARRAYS macro), to
+    accomodate making DLL's: Moved usr_png_ver from global variable to function
+    png_get_header_ver() in png.c.  Moved png_sig to png_sig_bytes in png.c and
+    eliminated use of png_sig in pngwutil.c.  Moved the various png_CHNK arrays
+    into pngtypes.h.  Eliminated use of global png_pass arrays.  Declared the
+    png_CHNK and png_pass arrays to be "const".  Made the global arrays
+    available to applications (although none are used in libpng itself) when
+    PNG_NO_GLOBAL_ARRAYS is not defined or when PNG_GLOBAL_ARRAYS is defined.
+  Removed some extraneous "-I" from contrib/pngminus/makefile.std
+  Changed the PNG_sRGB_INTENT macros in png.h to be consistent with PNG-1.2.
+  Change PNG_SRGB_INTENT to PNG_sRGB_INTENT in libpng.txt and libpng.3 
+version 1.0.5d [November 29, 1999]
+  Add type cast (png_const_charp) two places in png.c
+  Eliminated pngtypes.h; use macros instead to declare PNG_CHNK arrays.
+  Renamed "PNG_GLOBAL_ARRAYS" to "PNG_USE_GLOBAL_ARRAYS" and made available
+    to applications a macro "PNG_USE_LOCAL_ARRAYS".
+  #ifdef out all the new declarations when PNG_USE_GLOBAL_ARRAYS is defined.
+  Added PNG_EXPORT_VAR macro to accommodate making DLL's.

INSTALL

@@ -1,5 +1,5 @@
 
-Installing libpng version 1.0.2a - December 29, 1998
+Installing libpng version 1.0.5d - November 29, 1999
 
 Before installing libpng, you must first install zlib.  zlib
 can usually be found wherever you got libpng.  zlib can be
@@ -10,7 +10,7 @@ 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-1.0.2a" or "lpng103" and "zlib-1.1.3"
+might be called "libpng-1.0.5d" 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:
@@ -21,6 +21,10 @@ Your directory structure should look like this:
           README
           *.h
           *.c
+          contrib
+             gregbook
+             pngminus
+             pngsuite
           scripts
              makefile.*
           pngtest.png
@@ -38,37 +42,46 @@ 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
-      makefile.dec  =>  DEC Alpha UNIX makefile
-      makefile.sgi  =>  Silicon Graphics IRIX makefile
-      makefile.sun  =>  Sun makefile
-      makefile.s2x  =>  Solaris 2.X makefile (gcc, creates libpng.so.2.1.0)
-      makefile.lnx  =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.0)
-      makefile.mip  =>  MIPS makefile
-      makefile.aco  =>  Acorn makefile
-      makefile.ama  =>  Amiga makefile
-      smakefile.ppc =>  AMIGA smakefile for SAS C V6.58/7.00 PPC compiler
-                        (Requires SCOPTIONS, copied from scripts/SCOPTIONS.ppc)
-      makefile.atr  =>  Atari makefile
-      makefile.bor  =>  Borland makefile
-      build.bat     =>  MS-DOS batch file for Borland compiler
-      makefile.dj2  =>  DJGPP 2 makefile
-      makefile.msc  =>  Microsoft C makefile
-      makefile.w32  =>  makefile for Microsoft Visual C++ 4.0 and later
-      makefile.tc3  =>  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.wat  =>  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
+ 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.2.1.0.5d)
+ makefile.linux    =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.0.5d)
+ 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.vcawin32 =>  makefile for Microsoft Visual C++ 5.0 and later (uses
+                       assembler code)
+ makefile.vcwin32  =>  makefile for Microsoft Visual C++ 4.0 and later (does
+                       not use assembler code)
+ 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
+   MSDOS example: copy scripts\makefile.msc makefile
    UNIX example:    cp scripts/makefile.std makefile
 
 Read the makefile to see if you need to change any source or
@@ -80,11 +93,16 @@ 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.
+Look for "9782 zero samples" in the output of the test.  For more
+confidence, you can run another test by typing "pngtest pngnow.png"
+and looking for "289 zero samples" in the output.  Also, you can
+run "pngtest -m *.png" in the "contrib/pngsuite" directory and compare
+your output with the result shown in contrib/pngsuite/README.
 
 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.
+files, in the individual makefiles, in png.h, and the manual pages
+libpng.3 and png.5.

KNOWNBUG

@@ -1,5 +1,5 @@
 
-Known bugs and suggested enhancements in libpng-1.0.2
+Known bugs and suggested enhancements in libpng-1.0.5
 
 
 1. March 15, 1998 -- OPTIMIZATION -- Kevin Bracey
@@ -14,35 +14,12 @@ Known bugs and suggested enhancements in libpng-1.0.2
    Question whether i-- or --i is better.
 
    STATUS: Under investigation, postponed until after
-   libpng-1.0.2.  About 160 loops will be turned around
+   libpng-1.0.5.  About 160 loops will be turned around
    in libpng-1.0.Nn, for testing.
 
-2. June 15, 1998 -- BUG -- Evan Light
+2. July 4, 1998 -- ENHANCEMENT -- Glenn R-P
 
-   Under some conditions, 16-bit grayscale images aren't properly
-   expanded to rgb, because png_read_start_row() returns too small a
-   value of max_pixel_depth when png_set_filler() has also been called.
-
-   STATUS: Fixed in libpng-1.0.2a
-
-3. June 16, 1998 -- BUG -- Matt McConnell
-
-   When reading interlaced images with a progressive reader, in some
-   cases (interlaced images less than 3 pixels high) some passes are
-   not skipped that should be.
-
-   STATUS: Fixed in libpng-1.0.2a
-
-4. July 3, 1998 -- ENHANCEMENT -- Glenn R-P
-
-   Added png_set_rgb_to_gray() and png_get_rgb_to_gray_status() functions.
-
-   STATUS: Done in libpng-1.0.2a, awaiting comment on resulting test
-   images.
-
-5. July 4, 1998 -- ENHANCEMENT -- Glenn R-P
-
-   libpng-1.0.2 and earlier transform colors to gamma=1.0 space for
+   libpng-1.0.5 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
@@ -52,35 +29,31 @@ Known bugs and suggested enhancements in libpng-1.0.2
 
    STATUS: under development.
 
-6. August 20, 1998 -- BUG -- Kevin Bracey
+3. September 1999 -- ENHANCEMENT --
 
-   When using the filler transformation, the filler isn't written
-   into the leftmost pixel of each row.
+   It should be possible to use libpng without floating-point aritmetic.
 
-   Also, the filler operation isn't being done right when writing
-   files.  Some code that was removed from png_set_filler() in
-   libpng 1.0.1a shouldn't have been removed.
+   STATUS: Under investigation, implementation postponed until after
+   libpng-1.0.5.  The application interface will change because replacements
+   for the png_set_gAMA(), png_set_cHRM(), and corresponding png_get_()
+   functions will be needed.
 
-   STATUS: Fixed in libpng-1.0.2a
+4. October 1999 -- BUG
 
-7. August 23, 1998 -- BUG -- Duncan Simpson
+   pngvcrd.c is failing for interlaced PNGs that have empty passes.
 
-   "static pngcharp tIME_string" should be changed to
-   "static char tIME_string[30]" in pngtest.c
+   STATUS: A check for "width != 0" is required in several places.
+   Fixed in libpng-1.0.5a/1.0.6
 
-   STATUS: Fixed in libpng-1.0.2a
+5. October 1999 -- BUG
 
-8. August 24, 1998 -- BUG -- John Cromer
+   Under MSVC++6.0 with debugging enabled, heap corruption was detected
+   while destroying the png_write_ptr.
 
-   Order of byte-swap and shift operations seems to be incorrect in
-   png_do_write_transformations()
-
-   STATUS: Under investigation.
-
-9. September 11, 1998 -- ENHANCEMENT -- L. Peter Deutsch
-
-   The PNG_NO_STDIO macro should be split into PNG_NO_STDIO
-   and PNG_NO_CONSOLE_STDIO.
-
-   STATUS: Done in libpng-1.0.2a
+   STATUS:  This was fixed by modifying png_set_text (in pngset.c) to
+   refrain from writing into the user's text_ptr.  With this fix, however,
+   pngwrite.c, while destroying the info_ptr, was failing to free the
+   text->key strings.  Fix for the latter problem is to duplicate code
+   from png.c.
 
+   Fixed in libpng-1.0.5a/1.0.6

LICENSE

@@ -0,0 +1,70 @@
+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 1.0.5d, November 29, 1999)
+
+For the purposes of this copyright and license, "Contributing Authors"
+is defined as the following set of individuals:
+
+   John Bowler
+   Kevin Bracey
+   Sam Bushell
+   Andreas Dilger
+   Magnus Holmgren
+   Tom Lane
+   Dave Martindale
+   Glenn Randers-Pehrson
+   Greg Roelofs
+   Guy Eric Schalnat
+   Paul Schmidt
+   Tom Tanner
+   Willem van Schaik
+   Tim Wegner
+
+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.
+
+A "png_get_copyright" function is available, for convenient use in "about"
+boxes and the like:
+
+   printf("%s",png_get_copyright(NULL));
+
+Also, the PNG logo (in PNG format, of course) is supplied in the
+file "pngnow.png".
+
+Libpng is OSI Certified Open Source Software.  OSI Certified is a
+certification mark of the Open Source Initiative.
+
+Glenn Randers-Pehrson
+randeg@alum.rpi.edu
+November 29, 1999

README

@@ -1,14 +1,15 @@
-README for libpng 1.0.2a - December 29, 1998 (shared library 2.1)
+README for libpng 1.0.5d - November 29, 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
+Version 0.89 was the first official release of libpng.  Don't let the
+fact that it's the first release fool you.  The libpng library has been in
+extensive use and testing since mid-1995.  By late 1997 it had
+finally gotten to the stage where there hadn't been significant
 changes to the API in some time, and people have a bad feeling about
-libraries with versions < 1.0.
+libraries with versions < 1.0.  Version 1.0.0 was released in
+March 1998.
 
 ****
 Note that some of the changes to the png_info structure render this
@@ -28,8 +29,8 @@ 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.
+the new APIs (as shown in example.c and pngtest.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
@@ -49,8 +50,9 @@ 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@dworking.wustl.edu>
-and not on material submitted to Guy.
+on the PNG implementation mailing list <png-implement@ccrc.wustl.edu>
+and not on material submitted privately to Guy, Andreas, or Glenn.  They will
+forward any good suggestions to the list.
 
 For a detailed description on using libpng, read libpng.txt.  For
 examples of libpng in a program, see example.c and pngtest.c.  For usage
@@ -98,8 +100,8 @@ 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@alumni.rpi.edu
-png-implement@dworkin.wustl.edu
+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
@@ -108,7 +110,7 @@ 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@dworkin.wustl.edu.  I'll
+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,
@@ -126,8 +128,6 @@ Files in this distribution:
       CHANGES       =>  Description of changes between libpng versions
       README        =>  This file
       TODO          =>  Things not implemented in the current library
-      ansi2knr.1    =>  Manual page for ansi2knr
-      ansi2knr.c    =>  Converts files to K&R style function declarations
       build.bat     =>  MS-DOS batch file for Borland compiler
       descrip.mms   =>  VMS project file
       example.c     =>  Example code for using libpng functions
@@ -154,38 +154,56 @@ Files in this distribution:
       pngwrite.c    =>  High-level write functions
       pngwtran.c    =>  Write data transformations
       pngwutil.c    =>  Write utility functions
+      contrib       =>  Contributions
+       gregbook         =>  source code for PNG reading and writing, from
+                            Greg Roelofs' "PNG: The Definitive Guide",
+                            O'Reilly, 1999
+       pngminus     =>  Simple pnm2png and png2pnm programs
+       pngsuite     =>  Test images
       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
-        makefile.dec  =>  DEC Alpha UNIX makefile
-        makefile.sgi  =>  Silicon Graphics IRIX makefile
-        makefile.sun  =>  Sun makefile
-        makefile.s2x  =>  Solaris 2.X makefile (gcc, creates libpng.so.2.1.0)
-        makefile.lnx  =>  Linux/ELF makefile (gcc, creates libpng.so.2.1.0)
-        makefile.mip  =>  MIPS makefile
-        makefile.aco  =>  Acorn makefile
-        makefile.ama  =>  Amiga makefile
-        smakefile.ppc =>  AMIGA smakefile for SAS C V6.58/7.00 PPC compiler
-                          (Requires SCOPTIONS, copied from scripts/SCOPTIONS.ppc)
-        makefile.atr  =>  Atari makefile
-        makefile.bor  =>  Borland makefile
-        build.bat     =>  MS-DOS batch file for Borland compiler
-        makefile.dj2  =>  DJGPP 2 makefile
-        makefile.msc  =>  Microsoft C makefile
-        makefile.w32  =>  makefile for Microsoft Visual C++ 4.0 and later
-        makefile.tc3  =>  Turbo C 3.0 makefile
-        makefile.os2  =>  OS/2 Makefile (gcc and emx, requires pngos2.def)
-        makefile.wat  =>  Watcom 10a+ Makefile, 32-bit flat memory model
-        pngos2.def    =>  OS/2 module definition file used by makefile.os2
-        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
+       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.2.1.0.5d)
+       makefile.linux   =>  Linux/ELF makefile
+                            (gcc, creates libpng.so.2.1.0.5d)
+       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.vcawin32 => makefile for Microsoft Visual C++ 5.0 and
+                            later (uses assembler code)
+       makefile.vcwin32 =>  makefile for Microsoft Visual C++ 4.0 and
+                            later (does not use assembler code)
+       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@alumni.rpi.edu
+ Internet: randeg@alum.rpi.edu
  Web: http://www.rpi.edu/~randeg/index.html
 
 -Andreas Eric Dilger

TODO

@@ -10,7 +10,6 @@ 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.
-Color to gray transformation.
 Improved dithering.
 Multi-lingual error and warning message support.
 Complete sRGB transformation (presently it simply uses gamma=0.45455).
@@ -22,3 +21,4 @@ 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:
+   =========================
+      
+      November 29, 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 1.0.5d 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.1

@@ -1,36 +0,0 @@
-.TH ANSI2KNR 1 "19 Jan 1996"
-.SH NAME
-ansi2knr \- convert ANSI C to Kernighan & Ritchie C
-.SH SYNOPSIS
-.I ansi2knr
-[--varargs] input_file [output_file]
-.SH DESCRIPTION
-If no output_file is supplied, output goes to stdout.
-.br
-There are no error messages.
-.sp
-.I ansi2knr
-recognizes function definitions 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, and with a left brace as the first token on the
-following line (ignoring possible intervening comments).  It will recognize a
-multi-line header provided that no intervening line ends with a left or right
-brace or a semicolon.  These algorithms ignore whitespace and comments, except
-that the function name must be the first thing on the line.
-.sp
-The following constructs will confuse it:
-.br
-     - Any other construct that starts at the left margin and follows the
-above syntax (such as a macro or function call).
-.br
-     - Some macros that tinker with the syntax of the function header.
-.sp
-The --varargs switch is obsolete, and is recognized only for
-backwards compatibility.  The present version of
-.I ansi2knr
-will always attempt to convert a ... argument to va_alist and va_dcl.
-.SH AUTHOR
-L. Peter Deutsch <ghost@aladdin.com> wrote the original ansi2knr and
-continues to maintain the current version; most of the code in the current
-version is his work.  ansi2knr also includes contributions by Francois
-Pinard <pinard@iro.umontreal.ca> and Jim Avera <jima@netcom.com>.

ansi2knr.c

@@ -1,695 +0,0 @@
-/* ansi2knr.c */
-
-/* Convert ANSI C function definitions to K&R ("traditional C") syntax
-Copyright (C) 1989 Aladdin Enterprises.  All rights reserved.
-Copyright (C) 1988 Richard M. Stallman
-
-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 (the "GPL") for full details.
-
-Everyone is granted permission to copy, modify and redistribute ansi2knr,
-but only under the conditions described in the GPL.  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 COPYLEFT.
-[In the LIBPNG distribution, the GPL appears below, not in a separate file.]
-Among other things, the copyright notice and this notice must be preserved
-on all copies.
-
-We explicitly state here what we believe is already implied by the GPL: if
-the ansi2knr program is distributed as a separate source file and a
-separate executable file which are aggregated on a storage medium together
-with another program, this in itself does not bring the other program under
-the GPL, nor does the mere fact that such a program or the procedures for
-constructing it invoke the ansi2knr executable bring any other part of the
-program under the GPL.
-*/
-
-/*
----------- Here is the GNU GPL file COPYLEFT, referred to above ----------
------ These terms do NOT apply to the LIBPNG 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
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-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:
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-    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
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-    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
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-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
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-
-  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
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-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
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-NECESSARY SERVICING, REPAIR OR CORRECTION.
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-  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
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-(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 COPYLEFT ------------------------------
-*/
-
-/*
- * Usage:
-	ansi2knr input_file [output_file]
- * If no output_file is supplied, output goes to stdout.
- * There are no error messages.
- *
- * ansi2knr recognizes function definitions 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,
- * and with a left brace as the first token on the following line
- * (ignoring possible intervening comments).
- * It will recognize a multi-line header provided that no intervening
- * line ends with a left or right 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).
- *	- Some macros that tinker with the syntax of the function header.
- */
-
-/*
- * The original and principal author of ansi2knr is L. Peter Deutsch
- * <ghost@aladdin.com>.  Other authors are noted in the change history
- * that follows (in reverse chronological order):
-	lpd 96-01-21 added code to cope with not HAVE_CONFIG_H and with
-		compilers that don't understand void, as suggested by
-		Tom Lane
-	lpd 96-01-15 changed to require that the first non-comment token
-		on the line following a function header be a left brace,
-		to reduce sensitivity to macros, as suggested by Tom Lane
-		<tgl@sss.pgh.pa.us>
-	lpd 95-06-22 removed #ifndefs whose sole purpose was to define
-		undefined preprocessor symbols as 0; changed all #ifdefs
-		for configuration symbols to #ifs
-	lpd 95-04-05 changed copyright notice to make it clear that
-		including ansi2knr in a program does not bring the entire
-		program under the GPL
-	lpd 94-12-18 added conditionals for systems where ctype macros
-		don't handle 8-bit characters properly, suggested by
-		Francois Pinard <pinard@iro.umontreal.ca>;
-		removed --varargs switch (this is now the default)
-	lpd 94-10-10 removed CONFIG_BROKETS conditional
-	lpd 94-07-16 added some conditionals to help GNU `configure',
-		suggested by Francois Pinard <pinard@iro.umontreal.ca>;
-		properly erase prototype args in function parameters,
-		contributed by Jim Avera <jima@netcom.com>;
-		correct error in writeblanks (it shouldn't erase EOLs)
-	lpd 89-xx-xx original version
- */
-
-/* Most of the conditionals here are to make ansi2knr work with */
-/* or without the GNU configure machinery. */
-
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
-
-#include <stdio.h>
-#include <ctype.h>
-
-#if HAVE_CONFIG_H
-
-/*
-   For properly autoconfiguring ansi2knr, use AC_CONFIG_HEADER(config.h).
-   This will define HAVE_CONFIG_H and so, activate the following lines.
- */
-
-# if STDC_HEADERS || HAVE_STRING_H
-#  include <string.h>
-# else
-#  include <strings.h>
-# endif
-
-#else /* not HAVE_CONFIG_H */
-
-/* Otherwise do it the hard way */
-
-# ifdef BSD
-#  include <strings.h>
-# else
-#  ifdef VMS
-    extern int strlen(), strncmp();
-#  else
-#   include <string.h>
-#  endif
-# endif
-
-#endif /* not HAVE_CONFIG_H */
-
-#if STDC_HEADERS
-# include <stdlib.h>
-#else
-/*
-   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
-
-#endif
-
-/*
- * The ctype macros don't always handle 8-bit characters correctly.
- * Compensate for this here.
- */
-#ifdef isascii
-#  undef HAVE_ISASCII		/* just in case */
-#  define HAVE_ISASCII 1
-#else
-#endif
-#if STDC_HEADERS || !HAVE_ISASCII
-#  define is_ascii(c) 1
-#else
-#  define is_ascii(c) isascii(c)
-#endif
-
-#define is_space(c) (is_ascii(c) && isspace(c))
-#define is_alpha(c) (is_ascii(c) && isalpha(c))
-#define is_alnum(c) (is_ascii(c) && isalnum(c))
-
-/* Scanning macros */
-#define isidchar(ch) (is_alnum(ch) || (ch) == '_')
-#define isidfirstchar(ch) (is_alpha(ch) || (ch) == '_')
-
-/* Forward references */
-char *skipspace();
-int writeblanks();
-int test1();
-int convert1();
-
-/* The main program */
-int
-main(argc, argv)
-    int argc;
-    char *argv[];
-{	FILE *in, *out;
-#define bufsize 5000			/* arbitrary size */
-	char *buf;
-	char *line;
-	char *more;
-	/*
-	 * In previous versions, ansi2knr recognized a --varargs switch.
-	 * If this switch was supplied, ansi2knr would attempt to convert
-	 * a ... argument to va_alist and va_dcl; if this switch was not
-	 * supplied, ansi2knr would simply drop any such arguments.
-	 * Now, ansi2knr always does this conversion, and we only
-	 * check for this switch for backward compatibility.
-	 */
-	int convert_varargs = 1;
-
-	if ( argc > 1 && argv[1][0] == '-' )
-	  {	if ( !strcmp(argv[1], "--varargs") )
-		  {	convert_varargs = 1;
-			argc--;
-			argv++;
-		  }
-		else
-		  {	fprintf(stderr, "Unrecognized switch: %s\n", argv[1]);
-			exit(1);
-		  }
-	  }
-	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 output file %s\n", argv[2]);
-			exit(1);
-		   }
-	   }
-	in = fopen(argv[1], "r");
-	if ( in == NULL )
-	   {	fprintf(stderr, "Cannot open input file %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 )
-	   {
-test:		line += strlen(line);
-		switch ( test1(buf) )
-		   {
-		case 2:			/* a function header */
-			convert1(buf, out, 1, convert_varargs);
-			break;
-		case 1:			/* a function */
-			/* Check for a { at the start of the next line. */
-			more = ++line;
-f:			if ( line >= buf + (bufsize - 1) ) /* overflow check */
-			  goto wl;
-			if ( fgets(line, (unsigned)(buf + bufsize - line), in) == NULL )
-			  goto wl;
-			switch ( *skipspace(more, 1) )
-			  {
-			  case '{':
-			    /* Definitely a function header. */
-			    convert1(buf, out, 0, convert_varargs);
-			    fputs(more, out);
-			    break;
-			  case 0:
-			    /* The next line was blank or a comment: */
-			    /* keep scanning for a non-comment. */
-			    line += strlen(line);
-			    goto f;
-			  default:
-			    /* buf isn't a function header, but */
-			    /* more might be. */
-			    fputs(buf, out);
-			    strcpy(buf, more);
-			    line = buf;
-			    goto test;
-			  }
-			break;
-		case -1:		/* maybe the start of a function */
-			if ( line != buf + (bufsize - 1) ) /* overflow check */
-			  continue;
-			/* falls through */
-		default:		/* not a function */
-wl:			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 ( is_space(*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.
- * Don't overwrite end-of-line characters.
- */
-int
-writeblanks(start, end)
-    char *start;
-    char *end;
-{	char *p;
-	for ( p = start; p < end; p++ )
-	  if ( *p != '\r' && *p != '\n' )
-	    *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;
- *	2 - definitely a function prototype (NOT USED);
- *	-1 - may be the beginning of a function definition,
- *		append another line and look again.
- * The reason we don't attempt to convert function prototypes is that
- * Ghostscript's declaration-generating macros look too much like
- * prototypes, and confuse the algorithms.
- */
-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 = 0 /*2*/; break;
-	   case ')': contin = 1; break;
-	   case '{': return 0;		/* not a function */
-	   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;
-}
-
-/* Convert a recognized function definition or header to K&R syntax. */
-int
-convert1(buf, out, header, convert_varargs)
-    char *buf;
-    FILE *out;
-    int header;			/* Boolean */
-    int convert_varargs;	/* Boolean */
-{	char *endfn;
-	register char *p;
-	char **breaks;
-	unsigned num_breaks = 2;	/* for testing */
-	char **btop;
-	char **bp;
-	char **ap;
-	char *vararg = 0;
-
-	/* 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 *lp = NULL;
-		char *rp;
-		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 '(':
-				if ( !level ) lp = p;
-				level++;
-				break;
-			   case ')':
-				if ( --level < 0 ) end = p;
-				else rp = p;
-				break;
-			   case '/':
-				p = skipspace(p, 1) - 1;
-				break;
-			   default:
-				;
-			   }
-		   }
-		/* Erase any embedded prototype parameters. */
-		if ( lp )
-		  writeblanks(lp + 1, rp);
-		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] == '.' )
-		  {	if ( convert_varargs )
-			  {	*bp++ = "va_alist";
-				vararg = p-2;
-			  }
-			else
-			  {	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 and left parenthesis. */
-	p = buf;
-	while ( p != endfn ) putc(*p, out), p++;
-	/* Put out the declaration. */
-	if ( header )
-	  {	fputs(");", out);
-		for ( p = breaks[0]; *p; p++ )
-		  if ( *p == '\r' || *p == '\n' )
-		    putc(*p, out);
-	  }
-	else
-	  {	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] = ';';
-		if ( vararg != 0 )
-		  {	*vararg = 0;
-			fputs(breaks[0], out);		/* any prior args */
-			fputs("va_dcl", out);		/* the final arg */
-			fputs(bp[0], out);
-		  }
-		else
-		  fputs(breaks[0], out);
-	  }
-	free((char *)breaks);
-	return 0;
-}

contrib/gregbook/README

@@ -0,0 +1,52 @@
+PNG: The Definitive Guide: Source Code
+
+Chapters 13, 14 and 15 of PNG: The Definitive Guide discuss three
+cross-platform demo programs that show how to use the libpng reference
+library: rpng, rpng2 and wpng. rpng and rpng2 are viewers; the first is a
+very simple example that that shows how a standard file-viewer might use
+libpng, while the second is designed to process streaming data and shows how
+a web browser might be written. wpng is a simple command-line program that
+reads binary PPM files (the ``raw'' RGB subset of NetPBM) and converts them
+to PNG.
+
+The source code for all three demo programs currently compiles only under
+Unix and 32-bit Windows. It has been tested with gcc 2.7.2.3 under Linux and
+Solaris and with Microsoft Visual C++ 5.0 under Windows 95. Brief
+instructions for compiling the programs are included at the top of the
+makefiles; makefile.unx is the Unix version, and makefile.w32 is (you
+guessed it!) the version for 32-bit Windows. libpng and zlib are required.
+
+----------------------------------------------------------------------------
+
+License
+
+The source code to the demo programs may be used and distributed freely
+(even if you didn't buy the book--but feel free to do so at any time),
+subject to the terms of the following BSD-like license:
+
+     Copyright (c) 1998-1999 Greg Roelofs. All rights reserved.
+
+     This software is provided "as is," without warranty of any kind,
+     express or implied. In no event shall the author or contributors
+     be held liable for any damages arising in any way from the use of
+     this software.
+
+     Permission is granted to anyone to use this software for any
+     purpose, including commercial applications, and to alter it and
+     redistribute it freely, subject to the following restrictions:
+
+       1. Redistributions of source code must retain the above
+          copyright notice, disclaimer, and this list of conditions.
+       2. Redistributions in binary form must reproduce the above
+          copyright notice, disclaimer, and this list of conditions in
+          the documentation and/or other materials provided with the
+          distribution.
+       3. All advertising materials mentioning features or use of this
+          software must display the following acknowledgment:
+
+               This product includes software developed by Greg Roelofs
+               and contributors for the book, "PNG: The Definitive
+               Guide," published by O'Reilly and Associates.
+
+----------------------------------------------------------
+http://www.cdrom.com/pub/png/book/sources.html

contrib/gregbook/makefile.unx

@@ -0,0 +1,95 @@
+# Sample makefile for rpng-x / rpng2-x / wpng using gcc and make.
+# Greg Roelofs
+# Last modified:  16 February 1999
+#
+#	The programs built by this makefile are described in the book,
+#	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
+#	and family, too.  (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a shell prompt in the usual way; for example:
+#
+#	make -f makefile.unx
+#
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are both installed in /usr/local/{include,lib} (as indicated by the
+# PNGPATH and ZPATH macros below).  Edit as appropriate.
+#
+# This makefile builds statically linked executables (against libpng and zlib,
+# that is), but that can be changed by uncommenting the appropriate PNGLIB and
+# ZLIB lines.
+
+
+# macros --------------------------------------------------------------------
+
+PNGPATH = /usr/local
+PNGINC = -I$(PNGPATH)/include
+#PNGLIB = -L$(PNGPATH)/lib -lpng
+PNGLIB = $(PNGPATH)/lib/libpng.a
+
+ZPATH = /usr/local
+ZINC = -I$(ZPATH)/include
+#ZLIB = -L$(ZPATH)/lib -lz
+ZLIB = $(ZPATH)/lib/libz.a
+
+#XPATH = /usr/X11
+XPATH = /usr/X11R6
+XINC = -I$(XPATH)/include
+XLIB = -L$(XPATH)/lib -lX11
+
+INCS = $(PNGINC) $(ZINC) $(XINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(XLIB) -lm
+WLIBS = $(PNGLIB) $(ZLIB) -lm
+
+CC = gcc
+LD = gcc
+RM = rm -f
+CFLAGS = -O -Wall $(INCS)
+# [note that -Wall is a gcc-specific compilation flag ("all warnings on")]
+LDFLAGS =
+O = .o
+E =
+
+RPNG  = rpng-x
+RPNG2 = rpng2-x
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+	$(LD) $(LDFLAGS) -o $@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+	$(LD) $(LDFLAGS) -o $@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):	$(RPNG).c readpng.h
+$(RPNG2)$(O):	$(RPNG2).c readpng2.h
+$(WPNG)$(O):	$(WPNG).c writepng.h
+
+readpng$(O):	readpng.c readpng.h
+readpng2$(O):	readpng2.c readpng2.h
+writepng$(O):	writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+	$(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)

contrib/gregbook/makefile.w32

@@ -0,0 +1,112 @@
+# Sample makefile for rpng-win / rpng2-win / wpng using MSVC and NMAKE.
+# Greg Roelofs
+# Last modified:  16 February 1999
+#
+#	The programs built by this makefile are described in the book,
+#	"PNG:  The Definitive Guide," by Greg Roelofs (O'Reilly and
+#	Associates, 1999).  Go buy a copy, eh?  Buy some for friends
+#	and family, too.  (Not that this is a blatant plug or anything.)
+#
+# Invoke this makefile from a DOS prompt window via:
+#
+#	%devstudio%\vc\bin\vcvars32.bat
+#	nmake -nologo -f makefile.w32
+#
+# where %devstudio% is the installation directory for MSVC / DevStudio.  If
+# you get "environment out of space" errors, create a desktop shortcut with
+# "c:\windows\command.com /e:4096" as the program command line and set the
+# working directory to this directory.  Then double-click to open the new
+# DOS-prompt window with a bigger environment and retry the commands above.
+# 
+# This makefile assumes libpng and zlib have already been built or downloaded
+# and are in subdirectories at the same level as the current subdirectory
+# (as indicated by the PNGPATH and ZPATH macros below).  Edit as appropriate.
+#
+# Note that the names of the dynamic and static libpng and zlib libraries
+# used below may change in later releases of the libraries.  This makefile
+# builds statically linked executables, but that can be changed by uncom-
+# menting the appropriate PNGLIB and ZLIB lines.
+
+!include <ntwin32.mak>
+
+
+# macros --------------------------------------------------------------------
+
+PNGPATH = ../libpng
+PNGINC = -I$(PNGPATH)
+#PNGLIB = $(PNGPATH)/pngdll.lib
+PNGLIB = $(PNGPATH)/libpng.lib
+
+ZPATH = ../zlib
+ZINC = -I$(ZPATH)
+#ZLIB = $(ZPATH)/zlibdll.lib
+ZLIB = $(ZPATH)/zlibstat.lib
+
+WINLIBS = -defaultlib:user32.lib gdi32.lib
+# ["real" apps may also need comctl32.lib, comdlg32.lib, winmm.lib, etc.]
+
+INCS = $(PNGINC) $(ZINC)
+RLIBS = $(PNGLIB) $(ZLIB) $(WINLIBS)
+WLIBS = $(PNGLIB) $(ZLIB)
+
+CC = cl
+LD = link
+RM = del
+CFLAGS = -nologo -O -W3 $(INCS) $(cvars)
+# [note that -Wall is an MSVC-specific compilation flag ("all warnings on")]
+# [see %devstudio%\vc\include\win32.mak for cvars macro definition]
+O = .obj
+E = .exe
+
+RLDFLAGS = -nologo -subsystem:windows
+WLDFLAGS = -nologo
+
+RPNG  = rpng-win
+RPNG2 = rpng2-win
+WPNG  = wpng
+
+ROBJS  = $(RPNG)$(O) readpng$(O)
+ROBJS2 = $(RPNG2)$(O) readpng2$(O)
+WOBJS  = $(WPNG)$(O) writepng$(O)
+
+EXES = $(RPNG)$(E) $(RPNG2)$(E) $(WPNG)$(E)
+
+
+# implicit make rules -------------------------------------------------------
+
+.c$(O):
+	$(CC) -c $(CFLAGS) $<
+
+
+# dependencies --------------------------------------------------------------
+
+all:  $(EXES)
+
+$(RPNG)$(E): $(ROBJS)
+	$(LD) $(RLDFLAGS) -out:$@ $(ROBJS) $(RLIBS)
+
+$(RPNG2)$(E): $(ROBJS2)
+	$(LD) $(RLDFLAGS) -out:$@ $(ROBJS2) $(RLIBS)
+
+$(WPNG)$(E): $(WOBJS)
+	$(LD) $(WLDFLAGS) -out:$@ $(WOBJS) $(WLIBS)
+
+$(RPNG)$(O):	$(RPNG).c readpng.h
+$(RPNG2)$(O):	$(RPNG2).c readpng2.h
+$(WPNG)$(O):	$(WPNG).c writepng.h
+
+readpng$(O):	readpng.c readpng.h
+readpng2$(O):	readpng2.c readpng2.h
+writepng$(O):	writepng.c writepng.h
+
+
+# maintenance ---------------------------------------------------------------
+
+clean:
+#	ideally we could just do this:
+#	$(RM) $(EXES) $(ROBJS) $(ROBJS2) $(WOBJS)
+#	...but the Windows "DEL" command is none too bright, so:
+	$(RM) r*$(E)
+	$(RM) w*$(E)
+	$(RM) r*$(O)
+	$(RM) w*$(O)

contrib/gregbook/makevms.com

@@ -0,0 +1,104 @@
+$!------------------------------------------------------------------------------
+$! make Contrib programs of libpng under OpenVMS
+$!
+$!
+$! Look for the compiler used
+$!
+$ zlibsrc = "[---.zlib]"
+$ ccopt="/include=(''zlibsrc',[--])"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "[--]libpng.olb/lib"
+$ write lopt "''zlibsrc'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$ write sys$output "Compiling PNG contrib programs ..."
+$   CALL MAKE readpng.OBJ "cc ''CCOPT' readpng" -
+	readpng.c readpng.h
+$   CALL MAKE readpng2.OBJ "cc ''CCOPT' readpng2" -
+	readpng2.c readpng2.h
+$   CALL MAKE writepng.OBJ "cc ''CCOPT' writepng" -
+	writepng.c writepng.h
+$   write sys$output "Building rpng-x..."
+$   CALL MAKE rpng-x.OBJ "cc ''CCOPT' rpng-x" -
+	rpng-x.c readpng.h
+$   call make rpng-x.exe - 
+	"LINK rpng-x,readpng,lib.opt/opt,x11.opt/opt" - 
+	rpng-x.obj readpng.obj
+$   write sys$output "Building rpng2-x..."
+$   CALL MAKE rpng2-x.OBJ "cc ''CCOPT' rpng2-x" -
+	rpng2-x.c readpng2.h
+$   call make rpng2-x.exe - 
+	"LINK rpng2-x,readpng2,lib.opt/opt,x11.opt/opt" - 
+	rpng2-x.obj readpng2.obj
+$   write sys$output "Building wpng..."
+$   CALL MAKE wpng.OBJ "cc ''CCOPT' wpng" -
+	wpng.c writepng.h
+$   call make wpng.exe - 
+	"LINK wpng,writepng,lib.opt/opt" - 
+	wpng.obj writepng.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE

contrib/gregbook/readpng.c

@@ -0,0 +1,275 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readpng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "png.h"	/* libpng header; includes zlib.h */
+#include "readpng.h"	/* typedefs, common macros, public prototypes */
+
+
+static png_structp png_ptr = NULL;
+static png_infop info_ptr = NULL;
+
+png_uint_32  width, height;
+int  bit_depth, color_type;
+uch  *image_data = NULL;
+
+
+void readpng_version_info()
+{
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
+    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+      ZLIB_VERSION, zlib_version);
+} 
+
+
+/* return value = 0 for success, 1 for bad sig, 2 for bad IHDR, 4 for no mem */
+
+int readpng_init(FILE *infile, long *pWidth, long *pHeight)
+{
+    uch sig[8];
+
+
+    /* first do a quick check that the file really is a PNG image; could
+     * have used slightly more general png_sig_cmp() function instead */
+
+    fread(sig, 1, 8, infile);
+    if (!png_check_sig(sig, 8))
+        return 1;   /* bad signature */
+
+
+    /* could pass pointers to user-defined error handlers instead of NULLs: */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* we could create a second info struct here (end_info), but it's only
+     * useful if we want to keep pre- and post-IDAT chunk info separated
+     * (mainly for PNG-aware image editors and converters) */
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    png_init_io(png_ptr, infile);
+    png_set_sig_bytes(png_ptr, 8);  /* we already read the 8 signature bytes */
+
+    png_read_info(png_ptr, info_ptr);  /* read all PNG info up to image data */
+
+
+    /* alternatively, could make separate calls to png_get_image_width(),
+     * etc., but want bit_depth and color_type for later [don't care about
+     * compression_type and filter_type => NULLs] */
+
+    png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+      NULL, NULL, NULL);
+    *pWidth = width;
+    *pHeight = height;
+
+
+    /* OK, that's all we need for now; return happy */
+
+    return 0;
+}
+
+
+
+
+/* returns 0 if succeeds, 1 if fails due to no bKGD chunk, 2 if libpng error;
+ * scales values to 8-bit if necessary */
+
+int readpng_get_bgcolor(uch *red, uch *green, uch *blue)
+{
+    png_color_16p pBackground;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    if (!png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+        return 1;
+
+    /* it is not obvious from the libpng documentation, but this function
+     * takes a pointer to a pointer, and it always returns valid red, green
+     * and blue values, regardless of color_type: */
+
+    png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+
+    /* however, it always returns the raw bKGD data, regardless of any
+     * bit-depth transformations, so check depth and adjust if necessary */
+
+    if (bit_depth == 16) {
+        *red   = pBackground->red   >> 8;
+        *green = pBackground->green >> 8;
+        *blue  = pBackground->blue  >> 8;
+    } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+        if (bit_depth == 1)
+            *red = *green = *blue = pBackground->gray? 255 : 0;
+        else if (bit_depth == 2)
+            *red = *green = *blue = (255/3) * pBackground->gray;
+        else /* bit_depth == 4 */
+            *red = *green = *blue = (255/15) * pBackground->gray;
+    } else {
+        *red   = (uch)pBackground->red;
+        *green = (uch)pBackground->green;
+        *blue  = (uch)pBackground->blue;
+    }
+
+    return 0;
+}
+
+
+
+
+/* display_exponent == LUT_exponent * CRT_exponent */
+
+uch *readpng_get_image(double display_exponent, int *pChannels, ulg *pRowbytes)
+{
+    double  gamma;
+    png_uint_32  i, rowbytes;
+    png_bytepp  row_pointers = NULL;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(png_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return NULL;
+    }
+
+
+    /* expand palette images to RGB, low-bit-depth grayscale images to 8 bits,
+     * transparency chunks to full alpha channel; strip 16-bit-per-sample
+     * images to 8 bits per sample; and convert grayscale to RGB[A] */
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_expand(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+        png_set_expand(png_ptr);
+    if (bit_depth == 16)
+        png_set_strip_16(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png_ptr);
+
+
+    /* unlike the example in the libpng documentation, we have *no* idea where
+     * this file may have come from--so if it doesn't have a file gamma, don't
+     * do any correction ("do no harm") */
+
+    if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+        png_set_gamma(png_ptr, display_exponent, gamma);
+
+
+    /* all transformations have been registered; now update info_ptr data,
+     * get rowbytes and channels, and allocate image memory */
+
+    png_read_update_info(png_ptr, info_ptr);
+
+    *pRowbytes = rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+    *pChannels = (int)png_get_channels(png_ptr, info_ptr);
+
+    if ((image_data = (uch *)malloc(rowbytes*height)) == NULL) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return NULL;
+    }
+    if ((row_pointers = (png_bytepp)malloc(height*sizeof(png_bytep))) == NULL) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        free(image_data);
+        image_data = NULL;
+        return NULL;
+    }
+
+    Trace((stderr, "readpng_get_image:  rowbytes = %ld, height = %ld\n", rowbytes, height));
+
+
+    /* set the individual row_pointers to point at the correct offsets */
+
+    for (i = 0;  i < height;  ++i)
+        row_pointers[i] = image_data + i*rowbytes;
+
+
+    /* now we can go ahead and just read the whole image */
+
+    png_read_image(png_ptr, row_pointers);
+
+
+    /* and we're done!  (png_read_end() can be omitted if no processing of
+     * post-IDAT text/time/etc. is desired) */
+
+    free(row_pointers);
+    row_pointers = NULL;
+
+    png_read_end(png_ptr, NULL);
+
+    return image_data;
+}
+
+
+void readpng_cleanup(int free_image_data)
+{
+    if (free_image_data && image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (png_ptr && info_ptr) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        png_ptr = NULL;
+        info_ptr = NULL;
+    }
+}

contrib/gregbook/readpng.h

@@ -0,0 +1,64 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                              readpng.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+
+/* prototypes for public functions in readpng.c */
+
+void readpng_version_info(void);
+
+int readpng_init(FILE *infile, long *pWidth, long *pHeight);
+
+int readpng_get_bgcolor(uch *bg_red, uch *bg_green, uch *bg_blue);
+
+uch *readpng_get_image(double display_exponent, int *pChannels,
+                       ulg *pRowbytes);
+
+void readpng_cleanup(int free_image_data);

contrib/gregbook/readpng2.c

@@ -0,0 +1,419 @@
+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                 readpng2.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>	/* for exit() prototype */
+
+#include "png.h"	/* libpng header; includes zlib.h and setjmp.h */
+#include "readpng2.h"	/* typedefs, common macros, public prototypes */
+
+
+/* local prototypes */
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+                                 png_uint_32 row_num, int pass);
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr);
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+
+void readpng2_version_info()
+{
+    fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+      PNG_LIBPNG_VER_STRING, png_libpng_ver);
+    fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+      ZLIB_VERSION, zlib_version);
+} 
+
+
+
+
+int readpng2_check_sig(uch *sig, int num)
+{
+    return png_check_sig(sig, num);
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory */
+
+int readpng2_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;	/* note:  temporary variables! */
+    png_infop  info_ptr;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      readpng2_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_read_struct(&png_ptr, NULL, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* we could create a second info struct here (end_info), but it's only
+     * useful if we want to keep pre- and post-IDAT chunk info separated
+     * (mainly for PNG-aware image editors and converters) */
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or exit immediately, so here we are: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        return 2;
+    }
+
+
+    /* instead of doing png_init_io() here, now we set up our callback
+     * functions for progressive decoding */
+
+    png_set_progressive_read_fn(png_ptr, mainprog_ptr,
+      readpng2_info_callback, readpng2_row_callback, readpng2_end_callback);
+
+
+    /* make sure we save our pointers for use in readpng2_decode_data() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* and that's all there is to initialization */
+
+    return 0;
+}
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* setjmp() must be called in every function that calls a PNG-reading
+     * libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* hand off the next chunk of input data to libpng for decoding */
+
+    png_process_data(png_ptr, info_ptr, rawbuf, length);
+
+    return 0;
+}
+
+
+
+
+static void readpng2_info_callback(png_structp png_ptr, png_infop info_ptr)
+{
+    mainprog_info  *mainprog_ptr;
+    int  color_type, bit_depth;
+    double  gamma;
+
+
+    /* setjmp() doesn't make sense here, because we'd either have to exit(),
+     * longjmp() ourselves, or return control to libpng, which doesn't want
+     * to see us again.  By not doing anything here, libpng will instead jump
+     * to readpng2_decode_data(), which can return an error value to the main
+     * program. */
+
+
+    /* retrieve the pointer to our special-purpose struct, using the png_ptr
+     * that libpng passed back to us (i.e., not a global this time--there's
+     * no real difference for a single image, but for a multithreaded browser
+     * decoding several PNG images at the same time, one needs to avoid mixing
+     * up different images' structs) */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+    if (mainprog_ptr == NULL) {		/* we be hosed */
+        fprintf(stderr,
+          "readpng2 error:  main struct not recoverable in info_callback.\n");
+        fflush(stderr);
+        return;
+        /*
+         * Alternatively, we could call our error-handler just like libpng
+         * does, which would effectively terminate the program.  Since this
+         * can only happen if png_ptr gets redirected somewhere odd or the
+         * main PNG struct gets wiped, we're probably toast anyway.  (If
+         * png_ptr itself is NULL, we would not have been called.)
+         */
+    }
+
+
+    /* this is just like in the non-progressive case */
+
+    png_get_IHDR(png_ptr, info_ptr, &mainprog_ptr->width,
+      &mainprog_ptr->height, &bit_depth, &color_type, NULL, NULL, NULL);
+
+
+    /* since we know we've read all of the PNG file's "header" (i.e., up
+     * to IDAT), we can check for a background color here */
+
+    if (mainprog_ptr->need_bgcolor &&
+        png_get_valid(png_ptr, info_ptr, PNG_INFO_bKGD))
+    {
+        png_color_16p pBackground;
+
+        /* it is not obvious from the libpng documentation, but this function
+         * takes a pointer to a pointer, and it always returns valid red,
+         * green and blue values, regardless of color_type: */
+        png_get_bKGD(png_ptr, info_ptr, &pBackground);
+
+        /* however, it always returns the raw bKGD data, regardless of any
+         * bit-depth transformations, so check depth and adjust if necessary */
+        if (bit_depth == 16) {
+            mainprog_ptr->bg_red   = pBackground->red   >> 8;
+            mainprog_ptr->bg_green = pBackground->green >> 8;
+            mainprog_ptr->bg_blue  = pBackground->blue  >> 8;
+        } else if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) {
+            if (bit_depth == 1)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = pBackground->gray? 255 : 0;
+            else if (bit_depth == 2)
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/3) * pBackground->gray;
+            else /* bit_depth == 4 */
+                mainprog_ptr->bg_red = mainprog_ptr->bg_green =
+                  mainprog_ptr->bg_blue = (255/15) * pBackground->gray;
+        } else {
+            mainprog_ptr->bg_red   = (uch)pBackground->red;
+            mainprog_ptr->bg_green = (uch)pBackground->green;
+            mainprog_ptr->bg_blue  = (uch)pBackground->blue;
+        }
+    }
+
+
+    /* as before, let libpng expand palette images to RGB, low-bit-depth
+     * grayscale images to 8 bits, transparency chunks to full alpha channel;
+     * strip 16-bit-per-sample images to 8 bits per sample; and convert
+     * grayscale to RGB[A] */
+
+    if (color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_expand(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand(png_ptr);
+    if (png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS))
+        png_set_expand(png_ptr);
+    if (bit_depth == 16)
+        png_set_strip_16(png_ptr);
+    if (color_type == PNG_COLOR_TYPE_GRAY ||
+        color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png_ptr);
+
+
+    /* Unlike the basic viewer, which was designed to operate on local files,
+     * this program is intended to simulate a web browser--even though we
+     * actually read from a local file, too.  But because we are pretending
+     * that most of the images originate on the Internet, we follow the recom-
+     * mendation of the sRGB proposal and treat unlabelled images (no gAMA
+     * chunk) as existing in the sRGB color space.  That is, we assume that
+     * such images have a file gamma of 0.45455, which corresponds to a PC-like
+     * display system.  This change in assumptions will have no effect on a
+     * PC-like system, but on a Mac, SGI, NeXT or other system with a non-
+     * identity lookup table, it will darken unlabelled images, which effec-
+     * tively favors images from PC-like systems over those originating on
+     * the local platform.  Note that mainprog_ptr->display_exponent is the
+     * "gamma" value for the entire display system, i.e., the product of
+     * LUT_exponent and CRT_exponent. */
+
+    if (png_get_gAMA(png_ptr, info_ptr, &gamma))
+        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, gamma);
+    else
+        png_set_gamma(png_ptr, mainprog_ptr->display_exponent, 0.45455);
+
+
+    /* we'll let libpng expand interlaced images, too */
+
+    mainprog_ptr->passes = png_set_interlace_handling(png_ptr);
+
+
+    /* all transformations have been registered; now update info_ptr data and
+     * then get rowbytes and channels */
+
+    png_read_update_info(png_ptr, info_ptr);
+
+    mainprog_ptr->rowbytes = png_get_rowbytes(png_ptr, info_ptr);
+    mainprog_ptr->channels = png_get_channels(png_ptr, info_ptr);
+
+
+    /* Call the main program to allocate memory for the image buffer and
+     * initialize windows and whatnot.  (The old-style function-pointer
+     * invocation is used for compatibility with a few supposedly ANSI
+     * compilers that nevertheless barf on "fn_ptr()"-style syntax.) */
+
+    (*mainprog_ptr->mainprog_init)();
+
+
+    /* and that takes care of initialization */
+
+    return;
+}
+
+
+
+
+
+static void readpng2_row_callback(png_structp png_ptr, png_bytep new_row,
+                                  png_uint_32 row_num, int pass)
+{
+    mainprog_info  *mainprog_ptr;
+
+
+    /* first check whether the row differs from the previous pass; if not,
+     * nothing to combine or display */
+
+    if (!new_row)
+        return;
+
+
+    /* retrieve the pointer to our special-purpose struct so we can access
+     * the old rows and image-display callback function */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+    /* have libpng either combine the new row data with the existing row data
+     * from previous passes (if interlaced) or else just copy the new row
+     * into the main program's image buffer */
+
+    png_progressive_combine_row(png_ptr, mainprog_ptr->row_pointers[row_num],
+      new_row);
+
+
+    /* finally, call the display routine in the main program with the number
+     * of the row we just updated */
+
+    (*mainprog_ptr->mainprog_display_row)(row_num);
+
+
+    /* and we're ready for more */
+
+    return;
+}
+
+
+
+
+
+static void readpng2_end_callback(png_structp png_ptr, png_infop info_ptr)
+{
+    mainprog_info  *mainprog_ptr;
+
+
+    /* retrieve the pointer to our special-purpose struct */
+
+    mainprog_ptr = png_get_progressive_ptr(png_ptr);
+
+
+    /* let the main program know that it should flush any buffered image
+     * data to the display now and set a "done" flag or whatever, but note
+     * that it SHOULD NOT DESTROY THE PNG STRUCTS YET--in other words, do
+     * NOT call readpng2_cleanup() either here or in the finish_display()
+     * routine; wait until control returns to the main program via
+     * readpng2_decode_data() */
+
+    (*mainprog_ptr->mainprog_finish_display)();
+
+
+    /* all done */
+
+    return;
+}
+
+
+
+
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+
+    mainprog_ptr->png_ptr = NULL;
+    mainprog_ptr->info_ptr = NULL;
+}
+
+
+
+
+
+static void readpng2_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "readpng2 libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {		/* we are completely hosed now */
+        fprintf(stderr,
+          "readpng2 severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}

contrib/gregbook/readpng2.h

@@ -0,0 +1,85 @@
+/*---------------------------------------------------------------------------
+
+   rpng2 - progressive-model PNG display program                 readpng2.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+typedef struct _mainprog_info {
+    double display_exponent;
+    ulg width;
+    ulg height;
+    void *png_ptr;
+    void *info_ptr;
+    void (*mainprog_init)(void);
+    void (*mainprog_display_row)(ulg row_num);
+    void (*mainprog_finish_display)(void);
+    uch *image_data;
+    uch **row_pointers;
+    jmp_buf jmpbuf;
+    int passes;			/* not used */
+    int rowbytes;
+    int channels;
+    int need_bgcolor;
+    int done;
+    uch bg_red;
+    uch bg_green;
+    uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in readpng2.c */
+
+void readpng2_version_info(void);
+
+int readpng2_check_sig(uch *sig, int num);
+
+int readpng2_init(mainprog_info *mainprog_ptr);
+
+int readpng2_decode_data(mainprog_info *mainprog_ptr, uch *rawbuf, ulg length);
+
+void readpng2_cleanup(mainprog_info *mainprog_ptr);

contrib/gregbook/rpng-win.c

@@ -0,0 +1,600 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                             rpng-win.c
+
+   This program decodes and displays PNG images, with gamma correction and
+   optionally with a user-specified background color (in case the image has
+   transparency).  It is very nearly the most basic PNG viewer possible.
+   This version is for 32-bit Windows; it may compile under 16-bit Windows
+   with a little tweaking (or maybe not).
+
+   to do:
+    - stdout/stderr don't work!  need message window (maybe scrollable?)
+    - handle quoted command-line args (especially filenames with spaces)
+    - have minimum window width:  oh well
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng-win"
+#define LONGNAME  "Simple PNG Viewer for Windows"
+#define VERSION   "1.0 of 20 February 1999"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <windows.h>
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+#include "readpng.h"	/* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects
+ * only happen with alpha (which could easily be avoided with
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {			\
+    ush temp = ((ush)(fg)*(ush)(alpha) +				\
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);	\
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);			\
+}
+
+
+/* local prototypes */
+static int        rpng_win_create_window(HINSTANCE hInst, int showmode);
+static int        rpng_win_display_image(void);
+static void       rpng_win_cleanup(void);
+LRESULT CALLBACK  rpng_win_wndproc(HWND, UINT, WPARAM, LPARAM);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *progname = PROGNAME;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;	/* GRR:  not (yet) used */
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* Windows-specific variables */
+static ulg wimage_rowbytes;
+static uch *dib;
+static uch *wimage_data;
+static BITMAPINFOHEADER *bmih;
+
+static HWND global_hwnd;
+
+
+
+
+int WINAPI WinMain(HINSTANCE hInst, HINSTANCE hPrevInst, PSTR cmd, int showmode)
+{
+    char *args[1024];		/* arbitrary limit, but should suffice */
+    char *p, *q, **argv = args;
+    int argc = 0;
+    int rc, alen, flen;
+    int error = 0;
+    int have_bg = FALSE;
+    double LUT_exponent;		/* just the lookup table */
+    double CRT_exponent = 2.2;		/* just the monitor */
+    double default_display_exponent;	/* whole display system */
+    MSG msg;
+
+
+    filename = (char *)NULL;
+
+
+    /* First set the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities.  And
+     * yes, these ifdefs are completely wasted in a Windows program... */
+
+#if defined(NeXT)
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to get the
+     * "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;                 
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        display_exponent = atof(p);
+    else
+        display_exponent = default_display_exponent;
+
+
+    /* Windows really hates command lines, so we have to set up our own argv.
+     * Note that we do NOT bother with quoted arguments here, so don't use
+     * filenames with spaces in 'em! */
+
+    argv[argc++] = PROGNAME;
+    p = cmd;
+    for (;;) {
+        if (*p == ' ')
+            while (*++p == ' ')
+                ;
+        /* now p points at the first non-space after some spaces */
+        if (*p == '\0')
+            break;    /* nothing after the spaces:  done */
+        argv[argc++] = q = p;
+        while (*q && *q != ' ')
+            ++q;
+        /* now q points at a space or the end of the string */
+        if (*q == '\0')
+            break;    /* last argv already terminated; quit */
+        *q = '\0';    /* change space to terminator */
+        p = q + 1;
+    }
+    argv[argc] = NULL;   /* terminate the argv array itself */
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strcmp(*argv, "-gamma")) {
+            if (!*++argv)
+                ++error;
+            display_exponent = atof(*argv);
+            if (display_exponent <= 0.0)
+                ++error;
+        } else if (!strcmp(*argv, "-bgcolor")) {
+            if (!*++argv)
+                ++error;
+            bgstr = *argv;
+            if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                ++error;
+            else
+                have_bg = TRUE;
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename) {
+        ++error;
+    } else if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        if ((rc = readpng_init(infile, &image_width, &image_height)) != 0) {
+            switch (rc) {
+                case 1:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] is not a PNG file: incorrect signature\n",
+                      filename);
+                    break;
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n",
+                      filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng_init() error\n");
+                    break;
+            }
+            ++error;
+        }
+        if (error)
+            fclose(infile);
+    }
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+         "Usage:  %s [-gamma exp] [-bgcolor bg] file.png\n"
+         "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+         "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+         "\t\t  to the product of the lookup-table exponent (varies)\n"
+         "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+         "    bg  \tdesired background color in 7-character hex RGB format\n"
+         "\t\t  (e.g., ``#ff7f00'' for orange:  same as HTML colors);\n"
+         "\t\t  used with transparent images\n"
+         "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+         "\n", PROGNAME, default_display_exponent);
+        exit(1);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* if the user didn't specify a background color on the command line,
+     * check for one in the PNG file--if not, the initialized values of 0
+     * (black) will be used */
+
+    if (have_bg)
+        sscanf(bgstr+1, "%2x%2x%2x", &bg_red, &bg_green, &bg_blue);
+    else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+        readpng_cleanup(TRUE);
+        fprintf(stderr, PROGNAME
+          ":  libpng error while checking for background color\n");
+        exit(2);
+    }
+
+
+    /* do the basic Windows initialization stuff, make the window and fill it
+     * with the background color */
+
+    if (rpng_win_create_window(hInst, showmode))
+        exit(2);
+
+
+    /* decode the image, all at once */
+
+    Trace((stderr, "calling readpng_get_image()\n"))
+    image_data = readpng_get_image(display_exponent, &image_channels,
+      &image_rowbytes);
+    Trace((stderr, "done with readpng_get_image()\n"))
+
+
+    /* done with PNG file, so clean up to minimize memory usage (but do NOT
+     * nuke image_data!) */
+
+    readpng_cleanup(FALSE);
+    fclose(infile);
+
+    if (!image_data) {
+        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");
+        exit(3);
+    }
+
+
+    /* display image (composite with background if requested) */
+
+    Trace((stderr, "calling rpng_win_display_image()\n"))
+    if (rpng_win_display_image()) {
+        free(image_data);
+        exit(4);
+    }
+    Trace((stderr, "done with rpng_win_display_image()\n"))
+
+
+    /* wait for the user to tell us when to quit */
+
+    while (GetMessage(&msg, NULL, 0, 0)) {
+        TranslateMessage(&msg);
+        DispatchMessage(&msg);
+    }
+
+
+    /* OK, we're done:  clean up all image and Windows resources and go away */
+
+    rpng_win_cleanup();
+
+    return msg.wParam;
+}
+
+
+
+
+
+static int rpng_win_create_window(HINSTANCE hInst, int showmode)
+{
+    uch *dest;
+    int extra_width, extra_height;
+    ulg i, j;
+    WNDCLASSEX wndclass;
+
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the display-specific version of the image (round up
+    to multiple of 4 for Windows DIB).
+  ---------------------------------------------------------------------------*/
+
+    wimage_rowbytes = ((3*image_width + 3L) >> 2) << 2;
+
+    if (!(dib = (uch *)malloc(sizeof(BITMAPINFOHEADER) +
+                              wimage_rowbytes*image_height)))
+    {
+        return 4;	/* fail */
+    }
+
+/*---------------------------------------------------------------------------
+    Initialize the DIB.  Negative height means to use top-down BMP ordering
+    (must be uncompressed, but that's what we want).  Bit count of 1, 4 or 8
+    implies a colormap of RGBX quads, but 24-bit BMPs just use B,G,R values
+    directly => wimage_data begins immediately after BMP header.
+  ---------------------------------------------------------------------------*/
+
+    memset(dib, 0, sizeof(BITMAPINFOHEADER));
+    bmih = (BITMAPINFOHEADER *)dib;
+    bmih->biSize = sizeof(BITMAPINFOHEADER);
+    bmih->biWidth = image_width;
+    bmih->biHeight = -((long)image_height);
+    bmih->biPlanes = 1;
+    bmih->biBitCount = 24;
+    bmih->biCompression = 0;
+    wimage_data = dib + sizeof(BITMAPINFOHEADER);
+
+/*---------------------------------------------------------------------------
+    Fill in background color (black by default); data are in BGR order.
+  ---------------------------------------------------------------------------*/
+
+    for (j = 0;  j < image_height;  ++j) {
+        dest = wimage_data + j*wimage_rowbytes;
+        for (i = image_width;  i > 0;  --i) {
+            *dest++ = bg_blue;
+            *dest++ = bg_green;
+            *dest++ = bg_red;
+        }
+    }
+
+/*---------------------------------------------------------------------------
+    Set the window parameters.
+  ---------------------------------------------------------------------------*/
+
+    memset(&wndclass, 0, sizeof(wndclass));
+
+    wndclass.cbSize = sizeof(wndclass);
+    wndclass.style = CS_HREDRAW | CS_VREDRAW;
+    wndclass.lpfnWndProc = rpng_win_wndproc;
+    wndclass.hInstance = hInst;
+    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
+    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
+    wndclass.hbrBackground = (HBRUSH)GetStockObject(DKGRAY_BRUSH);
+    wndclass.lpszMenuName = NULL;
+    wndclass.lpszClassName = progname;
+    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
+
+    RegisterClassEx(&wndclass);
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    extra_width  = 2*(GetSystemMetrics(SM_CXBORDER) +
+                      GetSystemMetrics(SM_CXDLGFRAME));
+    extra_height = 2*(GetSystemMetrics(SM_CYBORDER) +
+                      GetSystemMetrics(SM_CYDLGFRAME)) +
+                      GetSystemMetrics(SM_CYCAPTION);
+
+    global_hwnd = CreateWindow(progname, titlebar, WS_OVERLAPPEDWINDOW,
+      CW_USEDEFAULT, CW_USEDEFAULT, image_width+extra_width,
+      image_height+extra_height, NULL, NULL, hInst, NULL);
+
+    ShowWindow(global_hwnd, showmode);
+    UpdateWindow(global_hwnd);
+
+    return 0;
+
+} /* end function rpng_win_create_window() */
+
+
+
+
+
+static int rpng_win_display_image()
+{
+    uch *src, *dest;
+    uch r, g, b, a;
+    ulg i, row, lastrow;
+    RECT rect;
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      image_channels))
+    Trace((stderr, "(width = %ld, rowbytes = %ld, wimage_rowbytes = %d)\n",
+      image_width, image_rowbytes, wimage_rowbytes))
+
+
+/*---------------------------------------------------------------------------
+    Blast image data to buffer.  This whole routine takes place before the
+    message loop begins, so there's no real point in any pseudo-progressive
+    display...
+  ---------------------------------------------------------------------------*/
+
+    for (lastrow = row = 0;  row < image_height;  ++row) {
+        src = image_data + row*image_rowbytes;
+        dest = wimage_data + row*wimage_rowbytes;
+        if (image_channels == 3) {
+            for (i = image_width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                *dest++ = b;
+                *dest++ = g;	/* note reverse order */
+                *dest++ = r;
+            }
+        } else /* if (image_channels == 4) */ {
+            for (i = image_width;  i > 0;  --i) {
+                r = *src++;
+                g = *src++;
+                b = *src++;
+                a = *src++;
+                if (a == 255) {
+                    *dest++ = b;
+                    *dest++ = g;
+                    *dest++ = r;
+                } else if (a == 0) {
+                    *dest++ = bg_blue;
+                    *dest++ = bg_green;
+                    *dest++ = bg_red;
+                } else {
+                    /* this macro (copied from png.h) composites the
+                     * foreground and background values and puts the
+                     * result into the first argument; there are no
+                     * side effects with the first argument */
+                    alpha_composite(*dest++, b, a, bg_blue);
+                    alpha_composite(*dest++, g, a, bg_green);
+                    alpha_composite(*dest++, r, a, bg_red);
+                }
+            }
+        }
+        /* display after every 16 lines */
+        if (((row+1) & 0xf) == 0) {
+            rect.left = 0L;
+            rect.top = (LONG)lastrow;
+            rect.right = (LONG)image_width;      /* possibly off by one? */
+            rect.bottom = (LONG)lastrow + 16L;   /* possibly off by one? */
+            InvalidateRect(global_hwnd, &rect, FALSE);
+            UpdateWindow(global_hwnd);     /* similar to XFlush() */
+            lastrow = row + 1;
+        }
+    }
+
+    Trace((stderr, "calling final image-flush routine\n"))
+    if (lastrow < image_height) {
+        rect.left = 0L;
+        rect.top = (LONG)lastrow;
+        rect.right = (LONG)image_width;      /* possibly off by one? */
+        rect.bottom = (LONG)image_height;    /* possibly off by one? */
+        InvalidateRect(global_hwnd, &rect, FALSE);
+        UpdateWindow(global_hwnd);     /* similar to XFlush() */
+    }
+
+/*
+    last param determines whether or not background is wiped before paint
+    InvalidateRect(global_hwnd, NULL, TRUE);
+    UpdateWindow(global_hwnd);
+ */
+
+    return 0;
+}
+
+
+
+
+
+static void rpng_win_cleanup()
+{
+    if (image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (dib) {
+        free(dib);
+        dib = NULL;
+    }
+}
+
+
+
+
+
+LRESULT CALLBACK rpng_win_wndproc(HWND hwnd, UINT iMsg, WPARAM wP, LPARAM lP)
+{
+    HDC         hdc;
+    PAINTSTRUCT ps;
+    int rc;
+
+    switch (iMsg) {
+        case WM_CREATE:
+            /* one-time processing here, if any */
+            return 0;
+
+        case WM_PAINT:
+            hdc = BeginPaint(hwnd, &ps);
+                    /*                    dest                          */
+            rc = StretchDIBits(hdc, 0, 0, image_width, image_height,
+                    /*                    source                        */
+                                    0, 0, image_width, image_height,
+                                    wimage_data, (BITMAPINFO *)bmih,
+                    /*              iUsage: no clue                     */
+                                    0, SRCCOPY);
+            EndPaint(hwnd, &ps);
+            return 0;
+
+        /* wait for the user to tell us when to quit */
+        case WM_CHAR:
+            switch (wP) {	/* only need one, so ignore repeat count */
+                case 'q':
+                case 'Q':
+                case 0x1B:	/* Esc key */
+                    PostQuitMessage(0);
+            }
+            return 0;
+
+        case WM_LBUTTONDOWN:	/* another way of quitting */
+        case WM_DESTROY:
+            PostQuitMessage(0);
+            return 0;
+    }
+
+    return DefWindowProc(hwnd, iMsg, wP, lP);
+}

contrib/gregbook/rpng-x.c

@@ -0,0 +1,741 @@
+/*---------------------------------------------------------------------------
+
+   rpng - simple PNG display program                               rpng-x.c
+
+   This program decodes and displays PNG images, with gamma correction and
+   optionally with a user-specified background color (in case the image has
+   transparency).  It is very nearly the most basic PNG viewer possible.
+   This version is for the X Window System (tested under Unix, but may work
+   under VMS or OS/2 with a little tweaking).
+
+   to do:
+    - 8-bit support
+    - use %.1023s to simplify truncation of title-bar string?
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "rpng-x"
+#define LONGNAME  "Simple PNG Viewer for X"
+#define VERSION   "1.01 of 31 March 1999"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/Xos.h>
+#include <X11/keysym.h>
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+#include "readpng.h"	/* typedefs, common macros, readpng prototypes */
+
+
+/* could just include png.h, but this macro is the only thing we need
+ * (name and typedefs changed to local versions); note that side effects 
+ * only happen with alpha (which could easily be avoided with 
+ * "ush acopy = (alpha);") */
+
+#define alpha_composite(composite, fg, alpha, bg) {			\
+    ush temp = ((ush)(fg)*(ush)(alpha) +				\
+                (ush)(bg)*(ush)(255 - (ush)(alpha)) + (ush)128);	\
+    (composite) = (uch)((temp + (temp >> 8)) >> 8);			\
+}
+
+
+/* local prototypes */
+static int  rpng_x_create_window(void);
+static int  rpng_x_display_image(void);
+static void rpng_x_cleanup(void);
+static int  rpng_x_msb(ulg u32val);
+
+
+static char titlebar[1024], *window_name = titlebar;
+static char *appname = LONGNAME;
+static char *icon_name = PROGNAME;
+static char *filename;
+static FILE *infile;
+
+static char *bgstr;
+static uch bg_red=0, bg_green=0, bg_blue=0;
+
+static double display_exponent;
+
+static ulg image_width, image_height, image_rowbytes;
+static int image_channels;
+static uch *image_data;
+
+/* X-specific variables */
+static char *displayname;
+static XImage *ximage;
+static Display *display;
+static int bitmap_order;
+static int depth;
+static Visual *visual;
+static int RPixelShift, GPixelShift, BPixelShift;
+static ulg RedMask, GreenMask, BlueMask;
+static Window window;
+static GC gc;
+static Colormap colormap;
+
+static int have_colormap = FALSE;
+static int have_window = FALSE;
+/*
+ulg numcolors=0, pixels[256];
+ush reds[256], greens[256], blues[256];
+ */
+
+
+
+
+int main(int argc, char **argv)
+{
+#ifdef sgi
+    char tmpline[80];
+#endif
+    char *p;
+    int rc, alen, flen;
+    int error = 0;
+    int have_bg = FALSE;
+    double LUT_exponent;		/* just the lookup table */
+    double CRT_exponent = 2.2;		/* just the monitor */
+    double default_display_exponent;	/* whole display system */
+    XEvent e;
+    KeySym k;
+
+
+    displayname = (char *)NULL;
+    filename = (char *)NULL;
+
+
+    /* First set the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  This is not an
+     * exhaustive list of LUT values (e.g., OpenStep has a lot of weird
+     * ones), but it should cover 99% of the current possibilities. */
+
+#if defined(NeXT)
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to get the
+     * "gamma" value, so we do it the hard way */
+    infile = fopen("/etc/config/system.glGammaVal", "r");
+    if (infile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, infile);
+        fclose(infile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL)
+        display_exponent = atof(p);
+    else
+        display_exponent = default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNG filename. */
+
+    while (*++argv && !error) {
+        if (!strcmp(*argv, "-display")) {
+            if (!*++argv)
+                ++error;
+            displayname = *argv;
+        } else if (!strcmp(*argv, "-gamma")) {
+            if (!*++argv)
+                ++error;
+            display_exponent = atof(*argv);
+            if (display_exponent <= 0.0)
+                ++error;
+        } else if (!strcmp(*argv, "-bgcolor")) {
+            if (!*++argv)
+                ++error;
+            bgstr = *argv;
+            if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                ++error;
+            else
+                have_bg = TRUE;
+        } else {
+            if (**argv != '-') {
+                filename = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+    if (!filename) {
+        ++error;
+    } else if (!(infile = fopen(filename, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open PNG file [%s]\n", filename);
+        ++error;
+    } else {
+        if ((rc = readpng_init(infile, (long *)(&image_width), 
+                               (long *)(&image_height))) != 0) {
+            switch (rc) {
+                case 1:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] is not a PNG file: incorrect signature\n",
+                      filename);
+                    break;
+                case 2:
+                    fprintf(stderr, PROGNAME
+                      ":  [%s] has bad IHDR (libpng longjmp)\n",
+                      filename);
+                    break;
+                case 4:
+                    fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                    break;
+                default:
+                    fprintf(stderr, PROGNAME
+                      ":  unknown readpng_init() error\n");
+                    break;
+            }
+            ++error;
+        } else {
+            display = XOpenDisplay(displayname);
+            if (!display) {
+                readpng_cleanup(TRUE);
+                fprintf(stderr, PROGNAME ":  can't open X display [%s]\n",
+                  displayname? displayname : "default");
+                ++error;
+            }
+        }
+        if (error)
+            fclose(infile);
+    }
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, appname);
+        readpng_version_info();
+        fprintf(stderr, "\n"
+         "Usage:  %s [-display xdpy] [-gamma exp] [-bgcolor bg] file.png\n"
+         "    xdpy\tname of the target X display (e.g., ``hostname:0'')\n"
+         "    exp \ttransfer-function exponent (``gamma'') of the display\n"
+         "\t\t  system in floating-point format (e.g., ``%.1f''); equal\n"
+         "\t\t  to the product of the lookup-table exponent (varies)\n"
+         "\t\t  and the CRT exponent (usually 2.2); must be positive\n"
+         "    bg  \tdesired background color in 7-character hex RGB format\n"
+         "\t\t  (e.g., ``#ff7f00'' for orange:  same as HTML colors);\n"
+         "\t\t  used with transparent images\n"
+         "\nPress Q, Esc or mouse button 1 after image is displayed to quit.\n"
+         "\n", PROGNAME, default_display_exponent);
+        exit(1);
+    }
+
+
+    /* set the title-bar string, but make sure buffer doesn't overflow */
+
+    alen = strlen(appname);
+    flen = strlen(filename);
+    if (alen + flen + 3 > 1023)
+        sprintf(titlebar, "%s:  ...%s", appname, filename+(alen+flen+6-1023));
+    else
+        sprintf(titlebar, "%s:  %s", appname, filename);
+
+
+    /* if the user didn't specify a background color on the command line,
+     * check for one in the PNG file--if not, the initialized values of 0
+     * (black) will be used */
+
+    if (have_bg) {
+        unsigned r, g, b;   /* this approach quiets compiler warnings */
+
+        sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+        bg_red   = (uch)r;
+        bg_green = (uch)g;
+        bg_blue  = (uch)b;
+    } else if (readpng_get_bgcolor(&bg_red, &bg_green, &bg_blue) > 1) {
+        readpng_cleanup(TRUE);
+        fprintf(stderr, PROGNAME
+          ":  libpng error while checking for background color\n");
+        exit(2);
+    }
+
+
+    /* do the basic X initialization stuff, make the window and fill it
+     * with the background color */
+
+    if (rpng_x_create_window())
+        exit(2);
+
+
+    /* decode the image, all at once */
+
+    Trace((stderr, "calling readpng_get_image()\n"))
+    image_data = readpng_get_image(display_exponent, &image_channels,
+      &image_rowbytes);
+    Trace((stderr, "done with readpng_get_image()\n"))
+
+
+    /* done with PNG file, so clean up to minimize memory usage (but do NOT
+     * nuke image_data!) */
+
+    readpng_cleanup(FALSE);
+    fclose(infile);
+
+    if (!image_data) {
+        fprintf(stderr, PROGNAME ":  unable to decode PNG image\n");
+        exit(3);
+    }
+
+
+    /* display image (composite with background if requested) */
+
+    Trace((stderr, "calling rpng_x_display_image()\n"))
+    if (rpng_x_display_image()) {
+        free(image_data);
+        exit(4);
+    }
+    Trace((stderr, "done with rpng_x_display_image()\n"))
+
+
+    /* wait for the user to tell us when to quit */
+
+    do
+        XNextEvent(display, &e);
+    while (!(e.type == ButtonPress && e.xbutton.button == Button1) &&
+           !(e.type == KeyPress &&    /*  v--- or 1 for shifted keys */
+             ((k = XLookupKeysym(&e.xkey, 0)) == XK_q || k == XK_Escape) ));
+
+
+    /* OK, we're done:  clean up all image and X resources and go away */
+
+    rpng_x_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+static int rpng_x_create_window()
+{
+    uch *xdata;
+    int screen, pad;
+    ulg bg_pixel = 0L;
+    Window root;
+    XEvent e;
+    XGCValues gcvalues;
+    XSetWindowAttributes attr;
+    XSizeHints *size_hints;
+    XTextProperty windowName, *pWindowName = &windowName;
+    XTextProperty iconName, *pIconName = &iconName;
+    XVisualInfo visual_info;
+    XWMHints *wm_hints;
+
+
+    bitmap_order = BitmapBitOrder(display);
+    screen = DefaultScreen(display);
+    depth = DisplayPlanes(display, screen);
+    root = RootWindow(display, screen);
+
+/* GRR:  add 8-bit support */
+    if (/* depth != 8 && */ depth != 16 && depth != 24 && depth != 32) {
+        fprintf(stderr,
+          "screen depth %d not supported (only 16-, 24- or 32-bit TrueColor)\n",
+          depth);
+        return 2;
+    }
+
+    XMatchVisualInfo(display, screen, depth,
+      (depth == 8)? PseudoColor : TrueColor, &visual_info);
+    visual = visual_info.visual;
+
+    RedMask   = visual->red_mask;
+    GreenMask = visual->green_mask;
+    BlueMask  = visual->blue_mask;
+
+/* GRR:  add/check 8-bit support */
+    if (depth == 8) {
+        colormap = XCreateColormap(display, root, visual, AllocNone);
+        if (!colormap) {
+            fprintf(stderr, "XCreateColormap() failed\n");
+            return 2;
+        }
+        have_colormap = TRUE;
+    } else if (depth == 16) {
+        RPixelShift = 15 - rpng_x_msb(RedMask);	/* these are right-shifts */
+        GPixelShift = 15 - rpng_x_msb(GreenMask);
+        BPixelShift = 15 - rpng_x_msb(BlueMask);
+    } else /* if (depth > 16) */ {
+        RPixelShift = rpng_x_msb(RedMask) - 7;	/* these are left-shifts */
+        GPixelShift = rpng_x_msb(GreenMask) - 7;
+        BPixelShift = rpng_x_msb(BlueMask) - 7;
+    }
+
+/*---------------------------------------------------------------------------
+    Finally, create the window.
+  ---------------------------------------------------------------------------*/
+
+    attr.backing_store = Always;
+    attr.event_mask = ExposureMask | KeyPressMask | ButtonPressMask;
+
+    window = XCreateWindow(display, root, 0, 0, image_width, image_height,
+      0, depth, InputOutput, visual, CWBackingStore | CWEventMask, &attr);
+
+    if (window == None) {
+        fprintf(stderr, "XCreateWindow() failed\n");
+        return 2;
+    } else
+        have_window = TRUE;
+
+    if (depth == 8)
+        XSetWindowColormap(display, window, colormap);
+
+    if (!XStringListToTextProperty(&window_name, 1, pWindowName))
+        pWindowName = NULL;
+    if (!XStringListToTextProperty(&icon_name, 1, pIconName))
+        pIconName = NULL;
+
+    /* OK if either hints allocation fails; XSetWMProperties() allows NULLs */
+
+    if ((size_hints = XAllocSizeHints()) != NULL) {
+        /* window will not be resizable */
+        size_hints->flags = PMinSize | PMaxSize;
+        size_hints->min_width = size_hints->max_width = image_width;
+        size_hints->min_height = size_hints->max_height = image_height;
+    }
+
+    if ((wm_hints = XAllocWMHints()) != NULL) {
+        wm_hints->initial_state = NormalState;
+        wm_hints->input = True;
+     /* wm_hints->icon_pixmap = icon_pixmap; */
+        wm_hints->flags = StateHint | InputHint  /* | IconPixmapHint */ ;
+    }
+
+    XSetWMProperties(display, window, pWindowName, pIconName, NULL, 0,
+      size_hints, wm_hints, NULL);
+
+    XMapWindow(display, window);
+
+    gc = XCreateGC(display, window, 0, &gcvalues);
+
+/*---------------------------------------------------------------------------
+    Fill window with the specified background color.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        bg_pixel = ((ulg)bg_red   << RPixelShift) |
+                   ((ulg)bg_green << GPixelShift) |
+                   ((ulg)bg_blue  << BPixelShift);
+    } else if (depth == 16) {
+        bg_pixel = ((((ulg)bg_red   << 8) >> RPixelShift) & RedMask)   |
+                   ((((ulg)bg_green << 8) >> GPixelShift) & GreenMask) |
+                   ((((ulg)bg_blue  << 8) >> BPixelShift) & BlueMask);
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    XSetForeground(display, gc, bg_pixel);
+    XFillRectangle(display, window, gc, 0, 0, image_width, image_height);
+
+/*---------------------------------------------------------------------------
+    Wait for first Expose event to do any drawing, then flush.
+  ---------------------------------------------------------------------------*/
+
+    do
+        XNextEvent(display, &e);
+    while (e.type != Expose || e.xexpose.count);
+
+    XFlush(display);
+
+/*---------------------------------------------------------------------------
+    Allocate memory for the X- and display-specific version of the image.
+  ---------------------------------------------------------------------------*/
+
+    if (depth == 24 || depth == 32) {
+        xdata = (uch *)malloc(4*image_width*image_height);
+        pad = 32;
+    } else if (depth == 16) {
+        xdata = (uch *)malloc(2*image_width*image_height);
+        pad = 16;
+    } else /* depth == 8 */ {
+        xdata = (uch *)malloc(image_width*image_height);
+        pad = 8;
+    }
+
+    if (!xdata) {
+        fprintf(stderr, PROGNAME ":  unable to allocate image memory\n");
+        return 4;
+    }
+
+    ximage = XCreateImage(display, visual, depth, ZPixmap, 0,
+      (char *)xdata, image_width, image_height, pad, 0);
+
+    if (!ximage) {
+        fprintf(stderr, PROGNAME ":  XCreateImage() failed\n");
+        free(xdata);
+        return 3;
+    }
+
+    /* to avoid testing the bitmap_order every pixel (or doubling the size of
+     * the drawing routine with a giant if-test), we arbitrarily set the byte
+     * order to MSBFirst and let Xlib worry about inverting things on little-
+     * endian machines (like Linux/x86, old VAXen, etc.)--this is not the most
+     * efficient approach (the giant if-test would be better), but in the
+     * interest of clarity, we take the easy way out... */
+
+    ximage->byte_order = MSBFirst;
+
+    return 0;
+
+} /* end function rpng_x_create_window() */
+
+
+
+
+
+static int rpng_x_display_image()
+{
+    uch *src;
+    char *dest;
+    uch r, g, b, a;
+    int ximage_rowbytes = ximage->bytes_per_line;
+    ulg i, row, lastrow = 0;
+    ulg pixel;
+
+
+    Trace((stderr, "beginning display loop (image_channels == %d)\n",
+      image_channels))
+    Trace((stderr, "(width = %ld, rowbytes = %ld, ximage_rowbytes = %d)\n",
+      image_width, image_rowbytes, ximage_rowbytes))
+
+    if (depth == 24 || depth == 32) {
+        ulg red, green, blue;
+
+        for (lastrow = row = 0;  row < image_height;  ++row) {
+            src = image_data + row*image_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (image_channels == 3) {
+                for (i = image_width;  i > 0;  --i) {
+                    red   = *src++;
+                    green = *src++;
+                    blue  = *src++;
+                    pixel = (red   << RPixelShift) |
+                            (green << GPixelShift) |
+                            (blue  << BPixelShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = ((uch *)&pixel)[3];
+                    *dest++ = ((uch *)&pixel)[2];
+                    *dest++ = ((uch *)&pixel)[1];
+                    *dest++ = ((uch *)&pixel)[0];
+                }
+            } else /* if (image_channels == 4) */ {
+                for (i = image_width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (a == 255) {
+                        red   = r;
+                        green = g;
+                        blue  = b;
+                    } else if (a == 0) {
+                        red   = bg_red;
+                        green = bg_green;
+                        blue  = bg_blue;
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result into the
+                         * first argument */
+                        alpha_composite(red,   r, a, bg_red);
+                        alpha_composite(green, g, a, bg_green);
+                        alpha_composite(blue,  b, a, bg_blue);
+                    }
+                    pixel = (red   << RPixelShift) |
+                            (green << GPixelShift) |
+                            (blue  << BPixelShift);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = ((uch *)&pixel)[3];
+                    *dest++ = ((uch *)&pixel)[2];
+                    *dest++ = ((uch *)&pixel)[1];
+                    *dest++ = ((uch *)&pixel)[0];
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, lastrow, 0, lastrow,
+                  image_width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else if (depth == 16) {
+        ush red, green, blue;
+
+        for (lastrow = row = 0;  row < image_height;  ++row) {
+            src = image_data + row*image_rowbytes;
+            dest = ximage->data + row*ximage_rowbytes;
+            if (image_channels == 3) {
+                for (i = image_width;  i > 0;  --i) {
+                    red   = ((ush)(*src) << 8);
+                    ++src;
+                    green = ((ush)(*src) << 8);
+                    ++src;
+                    blue  = ((ush)(*src) << 8);
+                    ++src;
+                    pixel = ((red   >> RPixelShift) & RedMask)   |
+                            ((green >> GPixelShift) & GreenMask) |
+                            ((blue  >> BPixelShift) & BlueMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = ((uch *)&pixel)[1];
+                    *dest++ = ((uch *)&pixel)[0];
+                }
+            } else /* if (image_channels == 4) */ {
+                for (i = image_width;  i > 0;  --i) {
+                    r = *src++;
+                    g = *src++;
+                    b = *src++;
+                    a = *src++;
+                    if (a == 255) {
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    } else if (a == 0) {
+                        red   = ((ush)bg_red   << 8);
+                        green = ((ush)bg_green << 8);
+                        blue  = ((ush)bg_blue  << 8);
+                    } else {
+                        /* this macro (from png.h) composites the foreground
+                         * and background values and puts the result back into
+                         * the first argument (== fg byte here:  safe) */
+                        alpha_composite(r, r, a, bg_red);
+                        alpha_composite(g, g, a, bg_green);
+                        alpha_composite(b, b, a, bg_blue);
+                        red   = ((ush)r << 8);
+                        green = ((ush)g << 8);
+                        blue  = ((ush)b << 8);
+                    }
+                    pixel = ((red   >> RPixelShift) & RedMask)   |
+                            ((green >> GPixelShift) & GreenMask) |
+                            ((blue  >> BPixelShift) & BlueMask);
+                    /* recall that we set ximage->byte_order = MSBFirst above */
+                    *dest++ = ((uch *)&pixel)[1];
+                    *dest++ = ((uch *)&pixel)[0];
+                }
+            }
+            /* display after every 16 lines */
+            if (((row+1) & 0xf) == 0) {
+                XPutImage(display, window, gc, ximage, 0, lastrow, 0, lastrow,
+                  image_width, 16);
+                XFlush(display);
+                lastrow = row + 1;
+            }
+        }
+
+    } else /* depth == 8 */ {
+
+        /* GRR:  add 8-bit support */
+
+    }
+
+    Trace((stderr, "calling final XPutImage()\n"))
+    if (lastrow < image_height) {
+        XPutImage(display, window, gc, ximage, 0, lastrow, 0, lastrow,
+          image_width, image_height-lastrow);
+        XFlush(display);
+    }
+
+    return 0;
+}
+
+
+
+
+static void rpng_x_cleanup()
+{
+    if (image_data) {
+        free(image_data);
+        image_data = NULL;
+    }
+
+    if (ximage) {
+        if (ximage->data) {
+            free(ximage->data);           /* we allocated it, so we free it */
+            ximage->data = (char *)NULL;  /*  instead of XDestroyImage() */
+        }
+        XDestroyImage(ximage);
+        ximage = NULL;
+    }
+
+    XFreeGC(display, gc);
+
+    if (have_window)
+        XDestroyWindow(display, window);
+
+    if (have_colormap)
+        XFreeColormap(display, colormap);
+}
+
+
+
+
+
+static int rpng_x_msb(ulg u32val)
+{
+    int i;
+
+    for (i = 31;  i >= 0;  --i) {
+        if (u32val & 0x80000000L)
+            break;
+        u32val <<= 1;
+    }
+    return i;
+}

contrib/gregbook/wpng.c

@@ -0,0 +1,804 @@
+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                                 wpng.c
+
+   This program converts certain NetPBM binary files (grayscale and RGB,
+   maxval = 255) to PNG.  Non-interlaced PNGs are written progressively;
+   interlaced PNGs are read and written in one memory-intensive blast.
+   Thanks to Jean-loup Gailly for providing the necessary trick to read
+   interactive text from the keyboard while stdin is redirected.
+
+   NOTE:  includes provisional support for PNM type "8" (portable alphamap)
+          images, presumed to be a 32-bit interleaved RGBA format; no pro-
+          vision for possible interleaved grayscale+alpha (16-bit) format.
+          THIS IS UNLIKELY TO BECOME AN OFFICIAL NETPBM ALPHA FORMAT!
+
+   to do:
+    - delete output file if quit before calling any writepng routines
+    - process backspace with -text option under DOS/Win? (currently get ^H)
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#define PROGNAME  "wpng"
+#define VERSION   "1.01 of 31 March 1999"
+#define APPNAME   "Simple PGM/PPM/PAM to PNG Converter"
+
+#if defined(__MSDOS__) || defined(__OS2__)
+#  define DOS_OS2_W32
+#elif defined(_WIN32) || defined(__WIN32__)
+#  define DOS_OS2_W32
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <setjmp.h>	/* for jmpbuf declaration in writepng.h */
+#include <time.h>
+
+#ifdef DOS_OS2_W32
+#  include <io.h>	/* for isatty(), setmode() prototypes */
+#  include <fcntl.h>	/* O_BINARY for fdopen() without text translation */
+#  ifdef __EMX__
+#    ifndef getch
+#      define getch() _read_kbd(0, 1, 0)	/* need getche() */
+#    endif
+#  else /* !__EMX__ */
+#    ifdef __GO32__
+#      include <pc.h>
+#      define getch() getkey()	/* GRR:  need getche() */
+#    else
+#      include <conio.h>	/* for getche() console input */
+#    endif
+#  endif /* ?__EMX__ */
+#  define FGETS(buf,len,stream)  dos_kbd_gets(buf,len)
+#else
+#  include <unistd.h>		/* for isatty() prototype */
+#  define FGETS fgets
+#endif
+
+/* #define DEBUG  :  this enables the Trace() macros */
+
+/* #define FORBID_LATIN1_CTRL  :  this requires the user to re-enter any
+   text that includes control characters discouraged by the PNG spec; text
+   that includes an escape character (27) must be re-entered regardless */
+
+#include "writepng.h"	/* typedefs, common macros, writepng prototypes */
+
+
+
+/* local prototypes */
+
+static int  wpng_isvalid_latin1(uch *p, int len);
+static void wpng_cleanup(void);
+
+#ifdef DOS_OS2_W32
+   static char *dos_kbd_gets(char *buf, int len);
+#endif
+
+
+
+static mainprog_info wpng_info;   /* lone global */
+
+
+
+int main(int argc, char **argv)
+{
+#ifndef DOS_OS2_W32
+    FILE *keybd;
+#endif
+#ifdef sgi
+    FILE *tmpfile;	/* or we could just use keybd, since no overlap */
+    char tmpline[80];
+#endif
+    char *inname = NULL, outname[256];
+    char *p, pnmchar, pnmline[256];
+    char *bgstr, *textbuf = NULL;
+    ulg rowbytes;
+    int rc, len = 0;
+    int error = 0;
+    int text = FALSE;
+    int maxval;
+    double LUT_exponent;                /* just the lookup table */
+    double CRT_exponent = 2.2;          /* just the monitor */
+    double default_display_exponent;    /* whole display system */
+    double default_gamma = 0.0;
+
+
+    wpng_info.infile = NULL;
+    wpng_info.outfile = NULL;
+    wpng_info.image_data = NULL;
+    wpng_info.row_pointers = NULL;
+    wpng_info.filter = FALSE;
+    wpng_info.interlaced = FALSE;
+    wpng_info.have_bg = FALSE;
+    wpng_info.have_time = FALSE;
+    wpng_info.have_text = 0;
+    wpng_info.gamma = 0.0;
+
+
+    /* First get the default value for our display-system exponent, i.e.,
+     * the product of the CRT exponent and the exponent corresponding to
+     * the frame-buffer's lookup table (LUT), if any.  If the PNM image
+     * looks correct on the user's display system, its file gamma is the
+     * inverse of this value.  (Note that this is not an exhaustive list
+     * of LUT values--e.g., OpenStep has a lot of weird ones--but it should
+     * cover 99% of the current possibilities.  This section must ensure
+     * that default_display_exponent is positive.) */
+
+#if defined(NeXT)
+    /* third-party utilities can modify the default LUT exponent */
+    LUT_exponent = 1.0 / 2.2;
+    /*
+    if (some_next_function_that_returns_gamma(&next_gamma))
+        LUT_exponent = 1.0 / next_gamma;
+     */
+#elif defined(sgi)
+    LUT_exponent = 1.0 / 1.7;
+    /* there doesn't seem to be any documented function to
+     * get the "gamma" value, so we do it the hard way */
+    tmpfile = fopen("/etc/config/system.glGammaVal", "r");
+    if (tmpfile) {
+        double sgi_gamma;
+
+        fgets(tmpline, 80, tmpfile);
+        fclose(tmpfile);
+        sgi_gamma = atof(tmpline);
+        if (sgi_gamma > 0.0)
+            LUT_exponent = 1.0 / sgi_gamma;
+    }
+#elif defined(Macintosh)
+    LUT_exponent = 1.8 / 2.61;
+    /*
+    if (some_mac_function_that_returns_gamma(&mac_gamma))
+        LUT_exponent = mac_gamma / 2.61;
+     */
+#else
+    LUT_exponent = 1.0;   /* assume no LUT:  most PCs */
+#endif
+
+    /* the defaults above give 1.0, 1.3, 1.5 and 2.2, respectively: */
+    default_display_exponent = LUT_exponent * CRT_exponent;
+
+
+    /* If the user has set the SCREEN_GAMMA environment variable as suggested
+     * (somewhat imprecisely) in the libpng documentation, use that; otherwise
+     * use the default value we just calculated.  Either way, the user may
+     * override this via a command-line option. */
+
+    if ((p = getenv("SCREEN_GAMMA")) != NULL) {
+        double exponent = atof(p);
+
+        if (exponent > 0.0)
+            default_gamma = 1.0 / exponent;
+    }
+
+    if (default_gamma == 0.0)
+        default_gamma = 1.0 / default_display_exponent;
+
+
+    /* Now parse the command line for options and the PNM filename. */
+
+    while (*++argv && !error) {
+        if (!strcmp(*argv, "-interlaced")) {
+            wpng_info.interlaced = TRUE;
+        } else if (!strcmp(*argv, "-time")) {
+            wpng_info.modtime = time(NULL);
+            wpng_info.have_time = TRUE;
+        } else if (!strcmp(*argv, "-text")) {
+            text = TRUE;
+        } else if (!strcmp(*argv, "-gamma")) {
+            if (!*++argv)
+                ++error;
+            wpng_info.gamma = atof(*argv);
+            if (wpng_info.gamma <= 0.0)
+                ++error;
+            else if (wpng_info.gamma > 1.01)
+                fprintf(stderr, PROGNAME
+                  " warning:  file gammas are usually less than 1.0\n");
+        } else if (!strcmp(*argv, "-bgcolor")) {
+            if (!*++argv)
+                ++error;
+            bgstr = *argv;
+            if (strlen(bgstr) != 7 || bgstr[0] != '#')
+                ++error;
+            else {
+                unsigned r, g, b;  /* this approach quiets compiler warnings */
+
+                sscanf(bgstr+1, "%2x%2x%2x", &r, &g, &b);
+                wpng_info.bg_red   = (uch)r;
+                wpng_info.bg_green = (uch)g;
+                wpng_info.bg_blue  = (uch)b;
+                wpng_info.have_bg = TRUE;
+            }
+        } else {
+            if (**argv != '-') {
+                inname = *argv;
+                if (argv[1])   /* shouldn't be any more args after filename */
+                    ++error;
+            } else
+                ++error;   /* not expecting any other options */
+        }
+    }
+
+
+    /* open the input and output files, or register an error and abort */
+
+    if (!inname) {
+        if (isatty(0)) {
+            fprintf(stderr, PROGNAME
+              ":  must give input filename or provide image data via stdin\n");
+            ++error;
+        } else {
+#ifdef DOS_OS2_W32
+            /* some buggy C libraries require BOTH setmode() and fdopen(bin) */
+            setmode(fileno(stdin), O_BINARY);
+            setmode(fileno(stdout), O_BINARY);
+#endif
+            if ((wpng_info.infile = fdopen(fileno(stdin), "rb")) == NULL) {
+                fprintf(stderr, PROGNAME
+                  ":  unable to reopen stdin in binary mode\n");
+                ++error;
+            } else
+            if ((wpng_info.outfile = fdopen(fileno(stdout), "wb")) == NULL) {
+                fprintf(stderr, PROGNAME
+                  ":  unable to reopen stdout in binary mode\n");
+                fclose(wpng_info.infile);
+                ++error;
+            } else 
+                wpng_info.filter = TRUE;
+        }
+    } else if ((len = strlen(inname)) > 250) {
+        fprintf(stderr, PROGNAME ":  input filename is too long [%d chars]\n",
+          len);
+        ++error;
+    } else if (!(wpng_info.infile = fopen(inname, "rb"))) {
+        fprintf(stderr, PROGNAME ":  can't open input file [%s]\n", inname);
+        ++error;
+    }
+
+    if (!error) {
+        fgets(pnmline, 256, wpng_info.infile);
+        if (pnmline[0] != 'P' || ((pnmchar = pnmline[1]) != '5' &&
+            pnmchar != '6' && pnmchar != '8'))
+        {
+            fprintf(stderr, PROGNAME
+              ":  input file [%s] is not a binary PGM, PPM or PAM file\n",
+              inname);
+            ++error;
+        } else {
+            wpng_info.pnmtype = (int)(pnmchar - '0');
+            if (wpng_info.pnmtype != 8)
+                wpng_info.have_bg = FALSE;  /* no need for bg if opaque */
+            do {
+                fgets(pnmline, 256, wpng_info.infile);  /* lose any comments */
+            } while (pnmline[0] == '#');
+            sscanf(pnmline, "%ld %ld", &wpng_info.width, &wpng_info.height);
+            do {
+                fgets(pnmline, 256, wpng_info.infile);  /* more comment lines */
+            } while (pnmline[0] == '#');
+            sscanf(pnmline, "%d", &maxval);
+            if (wpng_info.width <= 0L || wpng_info.height <= 0L ||
+                maxval != 255)
+            {
+                fprintf(stderr, PROGNAME
+                  ":  only positive width/height, maxval == 255 allowed \n");
+                ++error;
+            }
+            wpng_info.sample_depth = 8;  /* <==> maxval 255 */
+
+            if (!wpng_info.filter) {
+                /* make outname from inname */
+                if ((p = strrchr(inname, '.')) == NULL ||
+                    (p - inname) != (len - 4))
+                {
+                    strcpy(outname, inname);
+                    strcpy(outname+len, ".png");
+                } else {
+                    len -= 4;
+                    strncpy(outname, inname, len);
+                    strcpy(outname+len, ".png");
+                }
+                /* check if outname already exists; if not, open */
+                if ((wpng_info.outfile = fopen(outname, "rb")) != NULL) {
+                    fprintf(stderr, PROGNAME ":  output file exists [%s]\n",
+                      outname);
+                    fclose(wpng_info.outfile);
+                    ++error;
+                } else if (!(wpng_info.outfile = fopen(outname, "wb"))) {
+                    fprintf(stderr, PROGNAME ":  can't open output file [%s]\n",
+                      outname);
+                    ++error;
+                }
+            }
+        }
+        if (error) {
+            fclose(wpng_info.infile);
+            wpng_info.infile = NULL;
+            if (wpng_info.filter) {
+                fclose(wpng_info.outfile);
+                wpng_info.outfile = NULL;
+            }
+        }
+    }
+
+
+    /* if we had any errors, print usage and die horrible death...arrr! */
+
+    if (error) {
+        fprintf(stderr, "\n%s %s:  %s\n", PROGNAME, VERSION, APPNAME);
+        writepng_version_info();
+        fprintf(stderr, "\n"
+"Usage:  %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] pnmfile\n"
+"or: ... | %s [-gamma exp] [-bgcolor bg] [-text] [-time] [-interlace] | ...\n"
+         "    exp \ttransfer-function exponent (``gamma'') of the image in\n"
+         "\t\t  floating-point format (e.g., ``%.5f''); if image looks\n"
+         "\t\t  correct on given display system, image gamma is equal to\n"
+         "\t\t  inverse of display-system exponent, i.e., 1 / (LUT * CRT)\n"
+         "\t\t  (where LUT = lookup-table exponent and CRT = CRT exponent;\n"
+         "\t\t  first varies, second is usually 2.2, all are positive)\n"
+         "    bg  \tdesired background color for alpha-channel images, in\n"
+         "\t\t  7-character hex RGB format (e.g., ``#ff7f00'' for orange:\n"
+         "\t\t  same as HTML colors)\n"
+         "    -text\tprompt interactively for text info (tEXt chunks)\n"
+         "    -time\tinclude a tIME chunk (last modification time)\n"
+         "    -interlace\twrite interlaced PNG image\n"
+         "\n"
+"pnmfile or stdin must be a binary PGM (`P5'), PPM (`P6') or (extremely\n"
+"unofficial and unsupported!) PAM (`P8') file.  Currently it is required\n"
+"to have maxval == 255 (i.e., no scaling).  If pnmfile is specified, it\n"
+"is converted to the corresponding PNG file with the same base name but a\n"
+"``.png'' extension; files read from stdin are converted and sent to stdout.\n"
+"The conversion is progressive (low memory usage) unless interlacing is\n"
+"requested; in that case the whole image will be buffered in memory and\n"
+"written in one call.\n"
+         "\n", PROGNAME, PROGNAME, default_gamma);
+        exit(1);
+    }
+
+
+    /* prepare the text buffers for libpng's use; note that even though
+     * PNG's png_text struct includes a length field, we don't have to fill
+     * it out */
+
+    if (text &&
+#ifndef DOS_OS2_W32
+        (keybd = fdopen(fileno(stderr), "r")) != NULL &&
+#endif
+        (textbuf = (char *)malloc((5 + 9)*75)) != NULL)
+    {
+        int i, valid, result;
+
+        fprintf(stderr,
+          "Enter text info (no more than 72 characters per line);\n");
+        fprintf(stderr, "to skip a field, hit the <Enter> key.\n");
+        /* note:  just <Enter> leaves len == 1 */
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_TITLE_OFFSET;
+            fprintf(stderr, "  Title: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.title = p;
+                wpng_info.have_text |= TEXT_TITLE;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_TITLE;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {	/* escape character */
+                        wpng_info.have_text &= ~TEXT_TITLE;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_AUTHOR_OFFSET;
+            fprintf(stderr, "  Author: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.author = p;
+                wpng_info.have_text |= TEXT_AUTHOR;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_AUTHOR;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {	/* escape character */
+                        wpng_info.have_text &= ~TEXT_AUTHOR;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_DESC_OFFSET;
+            fprintf(stderr, "  Description (up to 9 lines):\n");
+            for (i = 1;  i < 10;  ++i) {
+                fprintf(stderr, "    [%d] ", i);
+                fflush(stderr);
+                if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1)
+                    p += len;   /* now points at NULL; char before is newline */
+                else
+                    break;
+            }
+            if ((len = p - (textbuf + TEXT_DESC_OFFSET)) > 1) {
+                if (p[-1] == '\n') {
+                    p[-1] = '\0';
+                    --len;
+                }
+                wpng_info.desc = textbuf + TEXT_DESC_OFFSET;
+                wpng_info.have_text |= TEXT_DESC;
+                p = textbuf + TEXT_DESC_OFFSET;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_DESC;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {	/* escape character */
+                        wpng_info.have_text &= ~TEXT_DESC;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_COPY_OFFSET;
+            fprintf(stderr, "  Copyright: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.copyright = p;
+                wpng_info.have_text |= TEXT_COPY;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_COPY;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {	/* escape character */
+                        wpng_info.have_text &= ~TEXT_COPY;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_EMAIL_OFFSET;
+            fprintf(stderr, "  E-mail: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.email = p;
+                wpng_info.have_text |= TEXT_EMAIL;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_EMAIL;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {	/* escape character */
+                        wpng_info.have_text &= ~TEXT_EMAIL;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+        do {
+            valid = TRUE;
+            p = textbuf + TEXT_URL_OFFSET;
+            fprintf(stderr, "  URL: ");
+            fflush(stderr);
+            if (FGETS(p, 74, keybd) && (len = strlen(p)) > 1) {
+                if (p[len-1] == '\n')
+                    p[--len] = '\0';
+                wpng_info.url = p;
+                wpng_info.have_text |= TEXT_URL;
+                if ((result = wpng_isvalid_latin1((uch *)p, len)) >= 0) {
+                    fprintf(stderr, "    " PROGNAME " warning:  character code"
+                      " %u is %sdiscouraged by the PNG\n    specification "
+                      "[first occurrence was at character position #%d]\n",
+                      (unsigned)p[result], (p[result] == 27)? "strongly " : "",
+                      result+1);
+                    fflush(stderr);
+#ifdef FORBID_LATIN1_CTRL
+                    wpng_info.have_text &= ~TEXT_URL;
+                    valid = FALSE;
+#else
+                    if (p[result] == 27) {	/* escape character */
+                        wpng_info.have_text &= ~TEXT_URL;
+                        valid = FALSE;
+                    }
+#endif
+                }
+            }
+        } while (!valid);
+
+#ifndef DOS_OS2_W32
+        fclose(keybd);
+#endif
+
+    } else if (text) {
+        fprintf(stderr, PROGNAME ":  unable to allocate memory for text\n");
+        text = FALSE;
+        wpng_info.have_text = 0;
+    }
+
+
+    /* allocate libpng stuff, initialize transformations, write pre-IDAT data */
+
+    if ((rc = writepng_init(&wpng_info)) != 0) {
+        switch (rc) {
+            case 2:
+                fprintf(stderr, PROGNAME
+                  ":  libpng initialization problem (longjmp)\n");
+                break;
+            case 4:
+                fprintf(stderr, PROGNAME ":  insufficient memory\n");
+                break;
+            case 11:
+                fprintf(stderr, PROGNAME
+                  ":  internal logic error (unexpected PNM type)\n");
+                break;
+            default:
+                fprintf(stderr, PROGNAME
+                  ":  unknown writepng_init() error\n");
+                break;
+        }
+        exit(rc);
+    }
+
+
+    /* free textbuf, since it's a completely local variable and all text info
+     * has just been written to the PNG file */
+
+    if (text && textbuf) {
+        free(textbuf);
+        textbuf = NULL;
+    }
+
+
+    /* calculate rowbytes on basis of image type; note that this becomes much
+     * more complicated if we choose to support PBM type, ASCII PNM types, or
+     * 16-bit-per-sample binary data [currently not an official NetPBM type] */
+
+    if (wpng_info.pnmtype == 5)
+        rowbytes = wpng_info.width;
+    else if (wpng_info.pnmtype == 6)
+        rowbytes = wpng_info.width * 3;
+    else /* if (wpng_info.pnmtype == 8) */
+        rowbytes = wpng_info.width * 4;
+
+
+    /* read and write the image, either in its entirety (if writing interlaced
+     * PNG) or row by row (if non-interlaced) */
+
+    fprintf(stderr, "Encoding image data...\n");
+    fflush(stderr);
+
+    if (wpng_info.interlaced) {
+        long i;
+        ulg bytes;
+        ulg image_bytes = rowbytes * wpng_info.height;   /* overflow? */
+
+        wpng_info.image_data = (uch *)malloc(image_bytes);
+        wpng_info.row_pointers = (uch **)malloc(wpng_info.height*sizeof(uch *));
+        if (wpng_info.image_data == NULL || wpng_info.row_pointers == NULL) {
+            fprintf(stderr, PROGNAME ":  insufficient memory for image data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(5);
+        }
+        for (i = 0;  i < wpng_info.height;  ++i)
+            wpng_info.row_pointers[i] = wpng_info.image_data + i*rowbytes;
+        bytes = fread(wpng_info.image_data, 1, image_bytes, wpng_info.infile);
+        if (bytes != image_bytes) {
+            fprintf(stderr, PROGNAME ":  expected %lu bytes, got %lu bytes\n",
+              image_bytes, bytes);
+            fprintf(stderr, "  (continuing anyway)\n");
+        }
+        if (writepng_encode_image(&wpng_info) != 0) {
+            fprintf(stderr, PROGNAME
+              ":  libpng problem (longjmp) while writing image data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+
+    } else /* not interlaced:  write progressively (row by row) */ {
+        long j;
+        ulg bytes;
+
+        wpng_info.image_data = (uch *)malloc(rowbytes);
+        if (wpng_info.image_data == NULL) {
+            fprintf(stderr, PROGNAME ":  insufficient memory for row data\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(5);
+        }
+        error = 0;
+        for (j = wpng_info.height;  j > 0L;  --j) {
+            bytes = fread(wpng_info.image_data, 1, rowbytes, wpng_info.infile);
+            if (bytes != rowbytes) {
+                fprintf(stderr, PROGNAME
+                  ":  expected %lu bytes, got %lu bytes (row %ld)\n", rowbytes,
+                  bytes, wpng_info.height-j);
+                ++error;
+                break;
+            }
+            if (writepng_encode_row(&wpng_info) != 0) {
+                fprintf(stderr, PROGNAME
+                  ":  libpng problem (longjmp) while writing row %ld\n",
+                  wpng_info.height-j);
+                ++error;
+                break;
+            }
+        }
+        if (error) {
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+        if (writepng_encode_finish(&wpng_info) != 0) {
+            fprintf(stderr, PROGNAME ":  error on final libpng call\n");
+            writepng_cleanup(&wpng_info);
+            wpng_cleanup();
+            exit(2);
+        }
+    }
+
+
+    /* OK, we're done (successfully):  clean up all resources and quit */
+
+    fprintf(stderr, "Done.\n");
+    fflush(stderr);
+
+    writepng_cleanup(&wpng_info);
+    wpng_cleanup();
+
+    return 0;
+}
+
+
+
+
+
+static int wpng_isvalid_latin1(uch *p, int len)
+{
+    int i, result = -1;
+
+    for (i = 0;  i < len;  ++i) {
+        if (p[i] == 10 || (p[i] > 31 && p[i] < 127) || p[i] > 160)
+            continue;		/* character is completely OK */
+        if (result < 0 || (p[result] != 27 && p[i] == 27))
+            result = i;		/* mark location of first questionable one */
+    }                  		/*  or of first escape character (bad) */
+
+    return result;
+}
+
+
+
+
+
+static void wpng_cleanup()
+{
+    if (wpng_info.outfile) {
+        fclose(wpng_info.outfile);
+        wpng_info.outfile = NULL;
+    }
+
+    if (wpng_info.infile) {
+        fclose(wpng_info.infile);
+        wpng_info.infile = NULL;
+    }
+
+    if (wpng_info.image_data) {
+        free(wpng_info.image_data);
+        wpng_info.image_data = NULL;
+    }
+
+    if (wpng_info.row_pointers) {
+        free(wpng_info.row_pointers);
+        wpng_info.row_pointers = NULL;
+    }
+}
+
+
+
+
+#ifdef DOS_OS2_W32
+
+static char *dos_kbd_gets(char *buf, int len)
+{
+    int ch, count=0;
+
+    do {
+        buf[count++] = ch = getche();
+    } while (ch != '\r' && count < len-1);
+
+    buf[count--] = '\0';	/* terminate string */
+    if (buf[count] == '\r')	/* Enter key makes CR, so change to newline */
+        buf[count] = '\n';
+
+    fprintf(stderr, "\n");	/* Enter key does *not* cause a newline */
+    fflush(stderr);
+
+    return buf;
+}
+
+#endif /* DOS_OS2_W32 */

contrib/gregbook/writepng.c

@@ -0,0 +1,368 @@
+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.c
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+
+#include <stdlib.h>	/* for exit() prototype */
+
+#include "png.h"	/* libpng header; includes zlib.h and setjmp.h */
+#include "writepng.h"	/* typedefs, common macros, public prototypes */
+
+
+/* local prototype */
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg);
+
+
+
+void writepng_version_info()
+{
+  fprintf(stderr, "   Compiled with libpng %s; using libpng %s.\n",
+    PNG_LIBPNG_VER_STRING, png_libpng_ver);
+  fprintf(stderr, "   Compiled with zlib %s; using zlib %s.\n",
+    ZLIB_VERSION, zlib_version);
+} 
+
+
+
+
+/* returns 0 for success, 2 for libpng problem, 4 for out of memory, 11 for
+ *  unexpected pnmtype; note that outfile might be stdout */
+
+int writepng_init(mainprog_info *mainprog_ptr)
+{
+    png_structp  png_ptr;       /* note:  temporary variables! */
+    png_infop  info_ptr;
+    int color_type, interlace_type;
+
+
+    /* could also replace libpng warning-handler (final NULL), but no need: */
+
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, mainprog_ptr,
+      writepng_error_handler, NULL);
+    if (!png_ptr)
+        return 4;   /* out of memory */
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (!info_ptr) {
+        png_destroy_write_struct(&png_ptr, NULL);
+        return 4;   /* out of memory */
+    }
+
+
+    /* setjmp() must be called in every function that calls a PNG-writing
+     * libpng function, unless an alternate error handler was installed--
+     * but compatible error handlers must either use longjmp() themselves
+     * (as in this program) or exit immediately, so here we go: */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 2;
+    }
+
+
+    /* make sure outfile is (re)opened in BINARY mode */
+
+    png_init_io(png_ptr, mainprog_ptr->outfile);
+
+
+    /* set the compression levels--in general, always want to leave filtering
+     * turned on (except for palette images) and allow all of the filters,
+     * which is the default; want 32K zlib window, unless entire image buffer
+     * is 16K or smaller (unknown here)--also the default; usually want max
+     * compression (NOT the default); and remaining compression flags should
+     * be left alone */
+
+    png_set_compression_level(png_ptr, Z_BEST_COMPRESSION);
+/*
+    >> this is default for no filtering; Z_FILTERED is default otherwise:
+    png_set_compression_strategy(png_ptr, Z_DEFAULT_STRATEGY);
+    >> these are all defaults:
+    png_set_compression_mem_level(png_ptr, 8);
+    png_set_compression_window_bits(png_ptr, 15);
+    png_set_compression_method(png_ptr, 8);
+ */
+
+
+    /* set the image parameters appropriately */
+
+    if (mainprog_ptr->pnmtype == 5)
+        color_type = PNG_COLOR_TYPE_GRAY;
+    else if (mainprog_ptr->pnmtype == 6)
+        color_type = PNG_COLOR_TYPE_RGB;
+    else if (mainprog_ptr->pnmtype == 8)
+        color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+    else {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        return 11;
+    }
+
+    interlace_type = mainprog_ptr->interlaced? PNG_INTERLACE_ADAM7 :
+                                               PNG_INTERLACE_NONE;
+
+    png_set_IHDR(png_ptr, info_ptr, mainprog_ptr->width, mainprog_ptr->height,
+      mainprog_ptr->sample_depth, color_type, interlace_type,
+      PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT);
+
+    if (mainprog_ptr->gamma > 0.0)
+        png_set_gAMA(png_ptr, info_ptr, mainprog_ptr->gamma);
+
+    if (mainprog_ptr->have_bg) {   /* we know it's RGBA, not gray+alpha */
+        png_color_16  background;
+
+        background.red = mainprog_ptr->bg_red;
+        background.green = mainprog_ptr->bg_green;
+        background.blue = mainprog_ptr->bg_blue;
+        png_set_bKGD(png_ptr, info_ptr, &background);
+    }
+
+    if (mainprog_ptr->have_time) {
+        png_time  modtime;
+
+        png_convert_from_time_t(&modtime, mainprog_ptr->modtime);
+        png_set_tIME(png_ptr, info_ptr, &modtime);
+    }
+
+    if (mainprog_ptr->have_text) {
+        png_text  text[6];
+        int  num_text = 0;
+
+        if (mainprog_ptr->have_text & TEXT_TITLE) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Title";
+            text[num_text].text = mainprog_ptr->title;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_AUTHOR) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Author";
+            text[num_text].text = mainprog_ptr->author;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_DESC) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Description";
+            text[num_text].text = mainprog_ptr->desc;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_COPY) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "Copyright";
+            text[num_text].text = mainprog_ptr->copyright;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_EMAIL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "E-mail";
+            text[num_text].text = mainprog_ptr->email;
+            ++num_text;
+        }
+        if (mainprog_ptr->have_text & TEXT_URL) {
+            text[num_text].compression = PNG_TEXT_COMPRESSION_NONE;
+            text[num_text].key = "URL";
+            text[num_text].text = mainprog_ptr->url;
+            ++num_text;
+        }
+        png_set_text(png_ptr, info_ptr, text, num_text);
+    }
+
+
+    /* write all chunks up to (but not including) first IDAT */
+
+    png_write_info(png_ptr, info_ptr);
+
+
+    /* if we wanted to write any more text info *after* the image data, we
+     * would set up text struct(s) here and call png_set_text() again, with
+     * just the new data; png_set_tIME() could also go here, but it would
+     * have no effect since we already called it above (only one tIME chunk
+     * allowed) */
+
+
+    /* set up the transformations:  for now, just pack low-bit-depth pixels
+     * into bytes (one, two or four pixels per byte) */
+
+    png_set_packing(png_ptr);
+/*  png_set_shift(png_ptr, &sig_bit);  to scale low-bit-depth values */
+
+
+    /* make sure we save our pointers for use in writepng_encode_image() */
+
+    mainprog_ptr->png_ptr = png_ptr;
+    mainprog_ptr->info_ptr = info_ptr;
+
+
+    /* OK, that's all we need to do for now; return happy */
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 for success, 2 for libpng (longjmp) problem */
+
+int writepng_encode_image(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* and now we just write the whole image; libpng takes care of interlacing
+     * for us */
+
+    png_write_image(png_ptr, mainprog_ptr->row_pointers);
+
+
+    /* since that's it, we also close out the end of the PNG file now--if we
+     * had any text or time info to write after the IDATs, second argument
+     * would be info_ptr, but we optimize slightly by sending NULL pointer: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_row(mainprog_info *mainprog_ptr)  /* NON-interlaced only! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* image_data points at our one row of image data */
+
+    png_write_row(png_ptr, mainprog_ptr->image_data);
+
+    return 0;
+}
+
+
+
+
+
+/* returns 0 if succeeds, 2 if libpng problem */
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr)   /* NON-interlaced! */
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+
+    /* as always, setjmp() must be called in every function that calls a
+     * PNG-writing libpng function */
+
+    if (setjmp(mainprog_ptr->jmpbuf)) {
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+        mainprog_ptr->png_ptr = NULL;
+        mainprog_ptr->info_ptr = NULL;
+        return 2;
+    }
+
+
+    /* close out PNG file; if we had any text or time info to write after
+     * the IDATs, second argument would be info_ptr: */
+
+    png_write_end(png_ptr, NULL);
+
+    return 0;
+}
+
+
+
+
+
+void writepng_cleanup(mainprog_info *mainprog_ptr)
+{
+    png_structp png_ptr = (png_structp)mainprog_ptr->png_ptr;
+    png_infop info_ptr = (png_infop)mainprog_ptr->info_ptr;
+
+    if (png_ptr && info_ptr)
+        png_destroy_write_struct(&png_ptr, &info_ptr);
+}
+
+
+
+
+
+static void writepng_error_handler(png_structp png_ptr, png_const_charp msg)
+{
+    mainprog_info  *mainprog_ptr;
+
+    /* This function, aside from the extra step of retrieving the "error
+     * pointer" (below) and the fact that it exists within the application
+     * rather than within libpng, is essentially identical to libpng's
+     * default error handler.  The second point is critical:  since both
+     * setjmp() and longjmp() are called from the same code, they are
+     * guaranteed to have compatible notions of how big a jmp_buf is,
+     * regardless of whether _BSD_SOURCE or anything else has (or has not)
+     * been defined. */
+
+    fprintf(stderr, "writepng libpng error: %s\n", msg);
+    fflush(stderr);
+
+    mainprog_ptr = png_get_error_ptr(png_ptr);
+    if (mainprog_ptr == NULL) {         /* we are completely hosed now */
+        fprintf(stderr,
+          "writepng severe error:  jmpbuf not recoverable; terminating.\n");
+        fflush(stderr);
+        exit(99);
+    }
+
+    longjmp(mainprog_ptr->jmpbuf, 1);
+}

contrib/gregbook/writepng.h

@@ -0,0 +1,109 @@
+/*---------------------------------------------------------------------------
+
+   wpng - simple PNG-writing program                             writepng.h
+
+  ---------------------------------------------------------------------------
+
+      Copyright (c) 1998-1999 Greg Roelofs.  All rights reserved.
+
+      This software is provided "as is," without warranty of any kind,
+      express or implied.  In no event shall the author or contributors
+      be held liable for any damages arising in any way from the use of
+      this software.
+
+      Permission is granted to anyone to use this software for any purpose,
+      including commercial applications, and to alter it and redistribute
+      it freely, subject to the following restrictions:
+
+      1. Redistributions of source code must retain the above copyright
+         notice, disclaimer, and this list of conditions.
+      2. Redistributions in binary form must reproduce the above copyright
+         notice, disclaimer, and this list of conditions in the documenta-
+         tion and/or other materials provided with the distribution.
+      3. All advertising materials mentioning features or use of this
+         software must display the following acknowledgment:
+
+            This product includes software developed by Greg Roelofs
+            and contributors for the book, "PNG: The Definitive Guide,"
+            published by O'Reilly and Associates.
+
+  ---------------------------------------------------------------------------*/
+
+#ifndef TRUE
+#  define TRUE 1
+#  define FALSE 0
+#endif
+
+#ifndef MAX
+#  define MAX(a,b)  ((a) > (b)? (a) : (b))
+#  define MIN(a,b)  ((a) < (b)? (a) : (b))
+#endif
+
+#ifdef DEBUG
+#  define Trace(x)  {fprintf x ; fflush(stderr); fflush(stdout);}
+#else
+#  define Trace(x)  ;
+#endif
+
+#define TEXT_TITLE    0x01
+#define TEXT_AUTHOR   0x02
+#define TEXT_DESC     0x04
+#define TEXT_COPY     0x08
+#define TEXT_EMAIL    0x10
+#define TEXT_URL      0x20
+
+#define TEXT_TITLE_OFFSET        0
+#define TEXT_AUTHOR_OFFSET      72
+#define TEXT_COPY_OFFSET     (2*72)
+#define TEXT_EMAIL_OFFSET    (3*72)
+#define TEXT_URL_OFFSET      (4*72)
+#define TEXT_DESC_OFFSET     (5*72)
+
+typedef unsigned char   uch;
+typedef unsigned short  ush;
+typedef unsigned long   ulg;
+
+typedef struct _mainprog_info {
+    double gamma;
+    long width;
+    long height;
+    time_t modtime;
+    FILE *infile;
+    FILE *outfile;
+    void *png_ptr;
+    void *info_ptr;
+    uch *image_data;
+    uch **row_pointers;
+    char *title;
+    char *author;
+    char *desc;
+    char *copyright;
+    char *email;
+    char *url;
+    int filter;    /* command-line-filter flag, not PNG row filter! */
+    int pnmtype;
+    int sample_depth;
+    int interlaced;
+    int have_bg;
+    int have_time;
+    int have_text;
+    jmp_buf jmpbuf;
+    uch bg_red;
+    uch bg_green;
+    uch bg_blue;
+} mainprog_info;
+
+
+/* prototypes for public functions in writepng.c */
+
+void writepng_version_info(void);
+
+int writepng_init(mainprog_info *mainprog_ptr);
+
+int writepng_encode_image(mainprog_info *mainprog_ptr);
+
+int writepng_encode_row(mainprog_info *mainprog_ptr);
+
+int writepng_encode_finish(mainprog_info *mainprog_ptr);
+
+void writepng_cleanup(mainprog_info *mainprog_ptr);

contrib/pngminus/README

@@ -0,0 +1,153 @@
+PngMinus 
+--------
+(copyright Willem van Schaik, 1999)
+
+
+License
+-------
+
+Permission to use, copy, modify, and distribute this software and
+its documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and
+that both that copyright notice and this permission notice appear in
+supporting documentation. This software is provided "as is" without
+express or implied warranty.
+
+
+Some history
+------------
+Soon after the creation of PNG in 1995, the need was felt for a set of
+pnmtopng / pngtopnm utilities. Independantly Alexander Lehmann and I
+(Willem van Schaik) started such a project. Luckily we discovered this
+and merged the two together into pnmtopng.tar.gz, which is available 
+from a/o ftp://swrinde.nde.swri.edu/pub/png/.
+
+These two utilities have many, many options and make use of most of the
+features of PNG, like gamma, alpha, sbit, text-chunks, etc. This makes
+the utilities quite complex and by now not anymore very maintainable.
+When we wrote these programs, libpng was still in an early stage.
+Therefore, lots of the functionality that we put in our software can now
+be done using transform-functions in libpng.
+
+Finally, to compile these programs, you need to have installed and
+compiled three libraries: libpng, zlib and netpbm. Especially the latter
+makes the whole setup a bit bulky. But that's unavoidable given the many
+features of pnmtopng.
+
+
+What now
+--------
+At this moment libpng is in a very stable state and can do much of the
+work done in pnmtopng. Also, pnmtopng needs to be upgraded to the new
+interface of libpng. Hence, it is time for a rewrite from the ground up
+of pnmtopng and pngtopnm. This will happen in the near future (stay
+tuned). The new package will get a different name to distinguish it from
+the old one: PngPlus.
+
+To experiment a bit with the new interface of libpng, I started off with
+a small prototype that contains only the basic functionality. It doesn't
+have any of the options to read or write special chunks and it will do
+no gamma correction. But this makes it also a simple program that is
+quite easy to understand and can serve well as a template for other
+software developments. (By now there are of course a couple of programs,
+like Greg Roelofs' rpng/wpng, that can be used just as good.)
+
+
+Can and can not
+---------------
+As this is the small brother of the future PngPlus, I called this fellow
+PngMinus. Because I started this development in good-old Turbo-C, I
+avoided the use the netpbm library, which requires DOS extenders. Again,
+another reason to call it PngMinus (minus netpbm :-). So, part of the
+program are some elementary routines to read / write pgm- and ppm-files.
+It does not read b&w pbm-files.
+
+The downside of this approach is that you can not use them on images
+that require blocks of memory bigger than 64k (the DOS version). For
+larger images you will get an out-of-memory error.
+
+As said before, PngMinus doesn't correct for gamma. When reading
+png-files you can do this just as well by piping the output of png2pnm
+to pnmgamma, one of the standard PbmPlus tools. This same scenario will
+most probably also be followed in the full-blown future PngPlus, with
+the addition of course of the possibility to create gamma-chunks when
+writing png-files.
+
+On the other hand it supports alpha-channels. When reading a png-image
+you can write the alpha-channel into a pgm-file. And when creating an
+RGB+A png-image, you just combine a ppm-file with a corresponding
+pgm-file containing the alpha-channel. When reading, transparency chunks
+are converted into an alpha-channel and from there on treated the same
+way.
+
+Finally you can opt for writing ascii or binary pgm- and ppm-files. When
+the bit-depth is 16, the format will always be ascii.
+
+
+Using it
+--------
+To distinguish them from pnmtopng and PngPlus, the utilities are named
+png2pnm and pnm2png (2 instead of to). The input- and output-files can
+be given as parameters or through redirection. Therefore the programs
+can be part of a pipe.
+
+To list the options type "png2pnm -h" or "pnm2png -h".
+
+
+Just like Scandinavian furniture
+--------------------------------
+You have to put it together yourself. I did test the software under
+MS-DOS with Turbo-C 3.0 and under RedHat Linux 4.2 with gcc. In both
+cases I used libpng-1.0.4 and zlib-1.1.3. Later versions should be OK,
+however some older libpng versions have a bug in pngmem.c when using
+Turbo-C 3.0 (see below).
+
+You can build it using one of the two makefiles (make -f makefile.###)
+or use the batch/script files pngminus.bat / pngminus.sh. This assumes
+that you have built the libraries in ../libpng and ../zlib. Using Linux,
+make sure that you have built libpng with makefile.std and not
+makefile.linux (also called .lnx in earlier versions of libpng). The
+latter creates a .so shared-library, while the PngMinus makefile assumes
+a normal .a static library.
+
+If you create a ../pngsuite directory and then store the basn####.png
+files from PngSuite (http://www.schaik.com/pngsuite/) in there, you can
+test in one go the proper functioning of PngMinus, see png2pnm.bat and
+pnm2png.bat (or the .sh versions).
+
+
+Warranty
+-------
+Please, remember that this was just a small experiment to learn a few
+things. It will have many unforeseen features <vbg>. Who said bugs? Use
+it when you are in need for something simple or when you want to start
+developing your own stuff.
+
+
+The Turbo bug
+-------------
+** pngmem.old
+          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+          hptr += 16L;
+** pngmem.c
+          hptr = (png_byte huge *)((long)(hptr) & 0xfffffff0L);
+          hptr = hptr + 16L;
+**
+
+** pngmem.old
+          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+          hptr += (png_uint_32)65536L;
+** pngmem.c
+          png_ptr->offset_table_ptr[i] = (png_bytep)hptr;
+          hptr = hptr + 65536L;
+**
+
+
+The end
+-------
+Willem van Schaik
+mailto:willem@schaik.com
+http://www.schaik.com/png/
+-------
+Oct 1999
+

contrib/pngminus/makefile.std

@@ -0,0 +1,52 @@
+# Makefile for PngMinus (png2pnm and pnm2png)
+# Linux / Unix
+
+CC=cc -O
+LD=cc -O
+#CC=gcc -O
+#LD=gcc -O
+LB=ar
+RM=rm
+CP=cp
+
+PNGPATH = /usr/local
+PNGINC = $(PNGPATH)/include
+#PNGLIB = $(PNGPATH)/lib -lpng
+PNGLIB = $(PNGPATH)/lib/libpng.a
+
+ZPATH = /usr/local
+ZINC = $(ZPATH)/include
+#ZLIB = $(ZPATH)/lib -lz
+ZLIB = $(ZPATH)/lib/libz.a
+
+CCFLAGS=-I$(PNGINC) -I$(ZINC)
+LDFLAGS=-L$(PNGLIB) -L$(ZLIB)
+C=.c
+O=.o
+L=.a
+E=
+
+# dependencies
+
+all: png2pnm$(E) pnm2png$(E)
+
+png2pnm$(O): png2pnm$(C)
+	$(CC) -c $(CCFLAGS) png2pnm$(C)
+
+png2pnm$(E): png2pnm$(O)
+	$(LD) -o png2pnm$(E) png2pnm$(O) $(LDFLAGS) -lpng -lz -lm
+
+pnm2png$(O): pnm2png$(C)
+	$(CC) -c $(CCFLAGS) pnm2png$(C)
+
+pnm2png$(E): pnm2png$(O)
+	$(LD) -o pnm2png$(E) pnm2png$(O) $(LDFLAGS) -lpng -lz -lm
+
+clean:
+	$(RM) png2pnm$(O)
+	$(RM) pnm2png$(O)
+	$(RM) png2pnm$(E)
+	$(RM) pnm2png$(E)
+
+# End of makefile for png2pnm / pnm2png
+

contrib/pngminus/makefile.tc3

@@ -0,0 +1,38 @@
+# Makefile for PngMinus (png2pnm and pnm2png)
+# TurboC++ 3.0
+
+CC=tcc -Ic:\tc3\inc
+LD=tcc -Lc:\tc3\lib
+LB=tlib
+RM=del
+CP=copy
+MODEL=l
+CCFLAGS=-O -m$(MODEL) -I..\libpng -I..\zlib
+LDFLAGS=-m$(MODEL) -L..\libpng -L..\zlib
+C=.c
+O=.obj
+L=.lib
+E=.exe
+
+# dependencies
+
+all: png2pnm$(E) pnm2png$(E)
+
+png2pnm$(O): png2pnm$(C)
+        $(CC) -c $(CCFLAGS) png2pnm$(C)
+
+png2pnm$(E): png2pnm$(O)
+        $(LD) $(LDFLAGS) png2pnm$(O) libpng$(L) zlib$(L)
+
+pnm2png$(O): pnm2png$(C)
+        $(CC) -c $(CCFLAGS) pnm2png$(C)
+
+pnm2png$(E): pnm2png$(O)
+        $(LD) $(LDFLAGS) pnm2png$(O) libpng$(L) zlib$(L)
+
+clean:
+        $(RM) *$(O)
+        $(RM) *$(E)
+
+# End of makefile for png2pnm / pnm2png
+

contrib/pngminus/makevms.com

@@ -0,0 +1,92 @@
+$!------------------------------------------------------------------------------
+$! make Contrib programs of libpng under OpenVMS
+$!
+$!
+$! Look for the compiler used
+$!
+$ zlibsrc = "[---.zlib]"
+$ ccopt="/include=(''zlibsrc',[--])"
+$ if f$getsyi("HW_MODEL").ge.1024
+$ then
+$  ccopt = "/prefix=all"+ccopt
+$  comp  = "__decc__=1"
+$  if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$ else
+$  if f$search("SYS$SYSTEM:DECC$COMPILER.EXE").eqs.""
+$   then
+$    if f$trnlnm("SYS").eqs."" then define sys sys$library:
+$    if f$search("SYS$SYSTEM:VAXC.EXE").eqs.""
+$     then
+$      comp  = "__gcc__=1"
+$      CC :== GCC
+$     else
+$      comp = "__vaxc__=1"
+$     endif
+$   else
+$    if f$trnlnm("SYS").eqs."" then define sys decc$library_include:
+$    ccopt = "/decc/prefix=all"+ccopt
+$    comp  = "__decc__=1"
+$  endif
+$ endif
+$ open/write lopt lib.opt
+$ write lopt "[--]libpng.olb/lib"
+$ write lopt "''zlibsrc'libz.olb/lib"
+$ close lopt
+$ open/write xopt x11.opt
+$ write xopt "sys$library:decw$xlibshr.exe/share"
+$ close xopt
+$ write sys$output "Compiling PNG contrib programs ..."
+$   write sys$output "Building pnm2png..."
+$   CALL MAKE pnm2png.OBJ "cc ''CCOPT' pnm2png" -
+	pnm2png.c
+$   call make pnm2png.exe - 
+	"LINK pnm2png,lib.opt/opt" - 
+	pnm2png.obj
+$   write sys$output "Building png2pnm..."
+$   CALL MAKE png2pnm.OBJ "cc ''CCOPT' png2pnm" -
+	png2pnm.c
+$   call make pnm2png.exe - 
+	"LINK pnm2png,lib.opt/opt" - 
+	pnm2png.obj
+$ exit
+$!
+$!
+$MAKE: SUBROUTINE   !SUBROUTINE TO CHECK DEPENDENCIES
+$ V = 'F$Verify(0)
+$! P1 = What we are trying to make
+$! P2 = Command to make it
+$! P3 - P8  What it depends on
+$
+$ If F$Search(P1) .Eqs. "" Then Goto Makeit
+$ Time = F$CvTime(F$File(P1,"RDT"))
+$arg=3
+$Loop:
+$       Argument = P'arg
+$       If Argument .Eqs. "" Then Goto Exit
+$       El=0
+$Loop2:
+$       File = F$Element(El," ",Argument)
+$       If File .Eqs. " " Then Goto Endl
+$       AFile = ""
+$Loop3:
+$       OFile = AFile
+$       AFile = F$Search(File)
+$       If AFile .Eqs. "" .Or. AFile .Eqs. OFile Then Goto NextEl
+$       If F$CvTime(F$File(AFile,"RDT")) .Ges. Time Then Goto Makeit
+$       Goto Loop3
+$NextEL:
+$       El = El + 1
+$       Goto Loop2
+$EndL:
+$ arg=arg+1
+$ If arg .Le. 8 Then Goto Loop
+$ Goto Exit
+$
+$Makeit:
+$ VV=F$VERIFY(0)
+$ write sys$output P2
+$ 'P2
+$ VV='F$Verify(VV)
+$Exit:
+$ If V Then Set Verify
+$ENDSUBROUTINE

contrib/pngminus/png2pnm.bat

@@ -0,0 +1,41 @@
+REM -- grayscale
+png2pnm.exe -noraw ..\pngsuite\basn0g01.png basn0g01.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g02.png basn0g02.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g04.png basn0g04.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g08.png basn0g08.pgm
+png2pnm.exe -noraw ..\pngsuite\basn0g16.png basn0g16.pgm
+REM -- full-color
+png2pnm.exe -noraw ..\pngsuite\basn2c08.png basn2c08.ppm
+png2pnm.exe -noraw ..\pngsuite\basn2c16.png basn2c16.ppm
+REM -- palletted
+png2pnm.exe -noraw ..\pngsuite\basn3p01.png basn3p01.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p02.png basn3p02.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p04.png basn3p04.ppm
+png2pnm.exe -noraw ..\pngsuite\basn3p08.png basn3p08.ppm
+REM -- gray with alpha-channel
+png2pnm.exe -noraw ..\pngsuite\basn4a08.png basn4a08.pgm
+png2pnm.exe -noraw ..\pngsuite\basn4a16.png basn4a16.pgm
+REM -- color with alpha-channel
+png2pnm.exe -noraw -alpha basn6a08.pgm ..\pngsuite\basn6a08.png basn6a08.ppm
+png2pnm.exe -noraw -alpha basn6a16.pgm ..\pngsuite\basn6a16.png basn6a16.ppm
+REM -- grayscale
+png2pnm.exe -raw ..\pngsuite\basn0g01.png rawn0g01.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g02.png rawn0g02.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g04.png rawn0g04.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g08.png rawn0g08.pgm
+png2pnm.exe -raw ..\pngsuite\basn0g16.png rawn0g16.pgm
+REM -- full-color
+png2pnm.exe -raw ..\pngsuite\basn2c08.png rawn2c08.ppm
+png2pnm.exe -raw ..\pngsuite\basn2c16.png rawn2c16.ppm
+REM -- palletted
+png2pnm.exe -raw ..\pngsuite\basn3p01.png rawn3p01.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p02.png rawn3p02.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p04.png rawn3p04.ppm
+png2pnm.exe -raw ..\pngsuite\basn3p08.png rawn3p08.ppm
+REM -- gray with alpha-channel
+png2pnm.exe -raw ..\pngsuite\basn4a08.png rawn4a08.pgm
+png2pnm.exe -raw ..\pngsuite\basn4a16.png rawn4a16.pgm
+REM -- color with alpha-channel
+png2pnm.exe -noraw -alpha rawn6a08.pgm ..\pngsuite\basn6a08.png rawn6a08.ppm
+png2pnm.exe -noraw -alpha rawn6a16.pgm ..\pngsuite\basn6a16.png rawn6a16.ppm
+

contrib/pngminus/png2pnm.c

@@ -0,0 +1,420 @@
+/*
+ *  png2pnm.c --- conversion from PNG-file to PGM/PPM-file
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
+ *
+ *  version 1.0 - 1999.10.15 - First version.
+ *
+ *  Permission to use, copy, modify, and distribute this software and
+ *  its documentation for any purpose and without fee is hereby granted,
+ *  provided that the above copyright notice appear in all copies and
+ *  that both that copyright notice and this permission notice appear in
+ *  supporting documentation. This software is provided "as is" without
+ *  express or implied warranty.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef __TURBOC__
+#include <mem.h>
+#include <fcntl.h>
+#endif
+
+#ifndef BOOL
+#define BOOL unsigned char
+#endif
+#ifndef TRUE
+#define TRUE (BOOL) 1
+#endif
+#ifndef FALSE
+#define FALSE (BOOL) 0
+#endif
+
+#ifdef __TURBOC__
+#define STDIN  0
+#define STDOUT 1
+#define STDERR 2
+#endif
+
+/* to make png2pnm verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#define PNG_DEBUG 0
+#endif
+
+#include "png.h"
+
+/* function prototypes */
+
+int  main (int argc, char *argv[]);
+void usage ();
+BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha);
+
+/*
+ *  main
+ */
+
+int main(int argc, char *argv[])
+{
+  FILE *fp_rd = stdin;
+  FILE *fp_wr = stdout;
+  FILE *fp_al = NULL;
+  BOOL raw = TRUE;
+  BOOL alpha = FALSE;
+  int argi;
+
+  for (argi = 1; argi < argc; argi++)
+  {
+    if (argv[argi][0] == '-')
+    {
+      switch (argv[argi][1])
+      {
+        case 'n':
+          raw = FALSE;
+          break;
+        case 'r':
+          raw = TRUE;
+          break;
+        case 'a':
+          alpha = TRUE;
+          argi++;
+          if ((fp_al = fopen (argv[argi], "wb")) == NULL)
+          {
+            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "Error:  can not create alpha-channel file %s\n", argv[argi]);
+            exit (1);
+          }
+          break;
+        case 'h':
+        case '?':
+          usage();
+          exit(0);
+          break;
+        default:
+          fprintf (stderr, "PNG2PNM\n");
+          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
+          usage();
+          exit(1);
+          break;
+      } /* end switch */
+    }
+    else if (fp_rd == stdin)
+    {
+      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
+      {
+             fprintf (stderr, "PNG2PNM\n");
+            fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
+            exit (1);
+      }
+    }
+    else if (fp_wr == stdout)
+    {
+      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
+      {
+        fprintf (stderr, "PNG2PNM\n");
+        fprintf (stderr, "Error:  can not create file %s\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else
+    {
+      fprintf (stderr, "PNG2PNM\n");
+      fprintf (stderr, "Error:  too many parameters\n");
+      usage();
+      exit(1);
+    }
+  } /* end for */
+
+#ifdef __TURBOC__
+  /* set stdin/stdout if required to binary */
+  if (fp_rd == stdin)
+  {
+    setmode (STDIN, O_BINARY);
+  }
+  if ((raw) && (fp_wr == stdout))
+  {
+    setmode (STDOUT, O_BINARY);
+  }
+#endif
+
+  /* call the conversion program itself */
+  if (png2pnm (fp_rd, fp_wr, fp_al, raw, alpha) == FALSE)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  unsuccessful convertion of PNG-image\n");
+    exit(1);
+  }
+
+  /* close input file */
+  fclose (fp_rd);
+  /* close output file */
+  fclose (fp_wr);
+  /* close alpha file */
+  if (alpha)
+    fclose (fp_al);
+
+  return 0;
+}
+
+/*
+ *  usage
+ */
+
+void usage()
+{
+  fprintf (stderr, "PNG2PNM\n");
+  fprintf (stderr, "   by Willem van Schaik, 1999\n");
+#ifdef __TURBOC__
+  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
+#else
+  fprintf (stderr, "   for Linux (and Unix) compilers\n");
+#endif
+  fprintf (stderr, "Usage:  png2pnm [options] <file>.png [<file>.pnm]\n");
+  fprintf (stderr, "   or:  ... | png2pnm [options]\n");
+  fprintf (stderr, "Options:\n");
+  fprintf (stderr, "   -r[aw]   write pnm-file in binary format (P4/P5/P6) (default)\n");
+  fprintf (stderr, "   -n[oraw] write pnm-file in ascii format (P1/P2/P3)\n");
+  fprintf (stderr, "   -a[lpha] <file>.pgm write PNG alpha channel as pgm-file\n");
+  fprintf (stderr, "   -h | -?  print this help-information\n");
+}
+
+/*
+ *  png2pnm
+ */
+
+BOOL png2pnm (FILE *png_file, FILE *pnm_file, FILE *alpha_file, BOOL raw, BOOL alpha)
+{
+  png_struct    *png_ptr = NULL;
+  png_info		*info_ptr = NULL;
+  png_byte      buf[8];
+  png_byte      *png_pixels = NULL;
+  png_byte      **row_pointers = NULL;
+  png_byte      *pix_ptr = NULL;
+  png_uint_32   row_bytes;
+
+  png_uint_32   width;
+  png_uint_32   height;
+  int           bit_depth;
+  int           channels;
+  int           color_type;
+  int           alpha_present;
+  int           row, col;
+  int           ret;
+  int           i;
+
+  /* read and check signature in PNG file */
+  ret = fread (buf, 1, 8, png_file);
+  if (ret != 8)
+    return FALSE;
+
+  ret = png_check_sig (buf, 8);
+  if (!ret)
+    return FALSE;
+
+  /* create png and info structures */
+
+  png_ptr = png_create_read_struct (PNG_LIBPNG_VER_STRING,
+    NULL, NULL, NULL);
+  if (!png_ptr)
+    return FALSE;   /* out of memory */
+
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr) 
+  {
+    png_destroy_read_struct (&png_ptr, NULL, NULL);
+    return FALSE;   /* out of memory */
+  }
+
+  if (setjmp (png_ptr->jmpbuf)) 
+  {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    return FALSE;
+  }
+
+  /* set up the input control for C streams */
+  png_init_io (png_ptr, png_file);
+  png_set_sig_bytes (png_ptr, 8);  /* we already read the 8 signature bytes */
+
+  /* read the file information */
+  png_read_info (png_ptr, info_ptr);
+
+  /* get size and bit-depth of the PNG-image */
+  png_get_IHDR (png_ptr, info_ptr, 
+    &width, &height, &bit_depth, &color_type,
+    NULL, NULL, NULL);
+
+  /* set-up the transformations */
+
+  /* transform paletted images into full-color rgb */
+  if (color_type == PNG_COLOR_TYPE_PALETTE)
+    png_set_expand (png_ptr);
+  /* expand images to bit-depth 8 (only applicable for grayscale images) */
+  if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+    png_set_expand (png_ptr);
+  /* transform transparency maps into full alpha-channel */
+  if (png_get_valid (png_ptr, info_ptr, PNG_INFO_tRNS))
+    png_set_expand (png_ptr);
+
+#ifdef NJET
+  /* downgrade 16-bit images to 8 bit */
+  if (bit_depth == 16)
+    png_set_strip_16 (png_ptr);
+  /* transform grayscale images into full-color */
+  if (color_type == PNG_COLOR_TYPE_GRAY ||
+    color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    png_set_gray_to_rgb (png_ptr);
+  /* only if file has a file gamma, we do a correction */
+  if (png_get_gAMA (png_ptr, info_ptr, &file_gamma))
+    png_set_gamma (png_ptr, (double) 2.2, file_gamma);
+#endif
+
+  /* all transformations have been registered; now update info_ptr data,
+   * get rowbytes and channels, and allocate image memory */
+
+  png_read_update_info (png_ptr, info_ptr);
+
+  /* get the new color-type and bit-depth (after expansion/stripping) */
+  png_get_IHDR (png_ptr, info_ptr, &width, &height, &bit_depth, &color_type,
+    NULL, NULL, NULL);
+
+  /* check for 16-bit files */
+  if (bit_depth == 16)
+  {
+    raw = FALSE;
+#ifdef __TURBOC__
+    pnm_file->flags &= ~((unsigned) _F_BIN);
+#endif
+  }
+
+  /* calculate new number of channels and store alpha-presence */
+  if (color_type == PNG_COLOR_TYPE_GRAY)
+    channels = 1;
+  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    channels = 2;
+  else if (color_type == PNG_COLOR_TYPE_RGB)
+    channels = 3;
+  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+    channels = 4;
+  else
+    channels = 0; /* should never happen */    
+  alpha_present = (channels - 1) % 2;
+
+  /* check if alpha is expected to be present in file */
+  if (alpha && !alpha_present)
+  {
+    fprintf (stderr, "PNG2PNM\n");
+    fprintf (stderr, "Error:  PNG-file doesn't contain alpha channel\n");
+    exit (1);
+  }
+
+  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+  row_bytes = png_get_rowbytes (png_ptr, info_ptr);
+
+  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL) {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    return FALSE;
+  }
+
+  if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL) 
+  {
+    png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+    free (png_pixels);
+    png_pixels = NULL;
+    return FALSE;
+  }
+
+  /* set the individual row_pointers to point at the correct offsets */
+  for (i = 0; i < (height); i++)
+    row_pointers[i] = png_pixels + i * row_bytes;
+
+  /* now we can go ahead and just read the whole image */
+  png_read_image (png_ptr, row_pointers);
+
+  /* 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 - REQUIRED */
+  png_destroy_read_struct (&png_ptr, &info_ptr, (png_infopp) NULL);
+
+  /* write header of PNM file */
+
+  if ((color_type == PNG_COLOR_TYPE_GRAY) ||
+      (color_type == PNG_COLOR_TYPE_GRAY_ALPHA))
+  {
+    fprintf (pnm_file, "%s\n", (raw) ? "P5" : "P2");
+    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
+    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+  else if ((color_type == PNG_COLOR_TYPE_RGB) ||
+           (color_type == PNG_COLOR_TYPE_RGB_ALPHA))
+  {
+    fprintf (pnm_file, "%s\n", (raw) ? "P6" : "P3");
+    fprintf (pnm_file, "%d %d\n", (int) width, (int) height);
+    fprintf (pnm_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+
+  /* write header of PGM file with alpha channel */
+
+  if ((alpha) &&
+      ((color_type == PNG_COLOR_TYPE_GRAY_ALPHA) ||
+       (color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
+  {
+    fprintf (alpha_file, "%s\n", (raw) ? "P5" : "P2");
+    fprintf (alpha_file, "%d %d\n", (int) width, (int) height);
+    fprintf (alpha_file, "%ld\n", ((1L << (int) bit_depth) - 1L));
+  }
+
+  /* write data to PNM file */
+  pix_ptr = png_pixels;
+
+  for (row = 0; row < height; row++)
+  {
+    for (col = 0; col < width; col++)
+    {
+      for (i = 0; i < (channels - alpha_present); i++)
+      {
+        if (raw)
+          fputc ((int) *pix_ptr++ , pnm_file);
+        else
+          if (bit_depth == 16)
+            fprintf (pnm_file, "%ld ", ((long) *pix_ptr++ << 8) + (long) *pix_ptr++);
+          else
+            fprintf (pnm_file, "%ld ", (long) *pix_ptr++);
+      }
+      if (alpha_present)
+      {
+        if (!alpha)
+        {
+          pix_ptr++; /* alpha */
+          if (bit_depth == 16)
+            pix_ptr++;
+        }
+        else /* output alpha-channel as pgm file */
+        {
+          if (raw)
+            fputc ((int) *pix_ptr++ , alpha_file);
+          else
+            if (bit_depth == 16)
+              fprintf (alpha_file, "%ld ", ((long) *pix_ptr++ << 8) + (long) *pix_ptr++);
+            else
+              fprintf (alpha_file, "%ld ", (long) *pix_ptr++);
+        }
+      } /* if alpha_present */
+
+      if (!raw)
+        if (col % 4 == 3)
+          fprintf (pnm_file, "\n");
+    } /* end for col */
+
+    if (!raw)
+      if (col % 4 != 0)
+        fprintf (pnm_file, "\n");
+  } /* end for row */
+
+  if (row_pointers != (unsigned char**) NULL)
+    free (row_pointers);
+  if (png_pixels != (unsigned char*) NULL)
+    free (png_pixels);
+
+  return TRUE;
+
+} /* end of source */
+

contrib/pngminus/png2pnm.sh

@@ -0,0 +1,41 @@
+# -- grayscale
+./png2pnm -noraw ../pngsuite/basn0g01.png basn0g01.pgm
+./png2pnm -noraw ../pngsuite/basn0g02.png basn0g02.pgm
+./png2pnm -noraw ../pngsuite/basn0g04.png basn0g04.pgm
+./png2pnm -noraw ../pngsuite/basn0g08.png basn0g08.pgm
+./png2pnm -noraw ../pngsuite/basn0g16.png basn0g16.pgm
+# -- full-color
+./png2pnm -noraw ../pngsuite/basn2c08.png basn2c08.ppm
+./png2pnm -noraw ../pngsuite/basn2c16.png basn2c16.ppm
+# -- palletted
+./png2pnm -noraw ../pngsuite/basn3p01.png basn3p01.ppm
+./png2pnm -noraw ../pngsuite/basn3p02.png basn3p02.ppm
+./png2pnm -noraw ../pngsuite/basn3p04.png basn3p04.ppm
+./png2pnm -noraw ../pngsuite/basn3p08.png basn3p08.ppm
+# -- gray with alpha-channel
+./png2pnm -noraw ../pngsuite/basn4a08.png basn4a08.pgm
+./png2pnm -noraw ../pngsuite/basn4a16.png basn4a16.pgm
+# -- color with alpha-channel
+./png2pnm -noraw -alpha basn6a08.pgm ../pngsuite/basn6a08.png basn6a08.ppm
+./png2pnm -noraw -alpha basn6a16.pgm ../pngsuite/basn6a16.png basn6a16.ppm
+# -- grayscale
+./png2pnm -raw ../pngsuite/basn0g01.png rawn0g01.pgm
+./png2pnm -raw ../pngsuite/basn0g02.png rawn0g02.pgm
+./png2pnm -raw ../pngsuite/basn0g04.png rawn0g04.pgm
+./png2pnm -raw ../pngsuite/basn0g08.png rawn0g08.pgm
+./png2pnm -raw ../pngsuite/basn0g16.png rawn0g16.pgm
+# -- full-color
+./png2pnm -raw ../pngsuite/basn2c08.png rawn2c08.ppm
+./png2pnm -raw ../pngsuite/basn2c16.png rawn2c16.ppm
+# -- palletted
+./png2pnm -raw ../pngsuite/basn3p01.png rawn3p01.ppm
+./png2pnm -raw ../pngsuite/basn3p02.png rawn3p02.ppm
+./png2pnm -raw ../pngsuite/basn3p04.png rawn3p04.ppm
+./png2pnm -raw ../pngsuite/basn3p08.png rawn3p08.ppm
+# -- gray with alpha-channel
+./png2pnm -raw ../pngsuite/basn4a08.png rawn4a08.pgm
+./png2pnm -raw ../pngsuite/basn4a16.png rawn4a16.pgm
+# -- color with alpha-channel
+./png2pnm -noraw -alpha rawn6a08.pgm ../pngsuite/basn6a08.png rawn6a08.ppm
+./png2pnm -noraw -alpha rawn6a16.pgm ../pngsuite/basn6a16.png rawn6a16.ppm
+

contrib/pngminus/pngminus.bat

@@ -0,0 +1,4 @@
+make -f makefile.tc3
+call png2pnm.bat
+call pnm2png.bat
+

contrib/pngminus/pngminus.sh

@@ -0,0 +1,4 @@
+make -f makefile.std
+sh png2pnm.sh
+sh pnm2png.sh
+

contrib/pngminus/pnm2png.bat

@@ -0,0 +1,41 @@
+REM -- grayscale
+pnm2png.exe basn0g01.pgm basn0g01.png
+pnm2png.exe basn0g02.pgm basn0g02.png
+pnm2png.exe basn0g04.pgm basn0g04.png
+pnm2png.exe basn0g08.pgm basn0g08.png
+pnm2png.exe basn0g16.pgm basn0g16.png
+REM -- full-color
+pnm2png.exe basn2c08.ppm basn2c08.png
+pnm2png.exe basn2c16.ppm basn2c16.png
+REM -- palletted
+pnm2png.exe basn3p01.ppm basn3p01.png
+pnm2png.exe basn3p02.ppm basn3p02.png
+pnm2png.exe basn3p04.ppm basn3p04.png
+pnm2png.exe basn3p08.ppm basn3p08.png
+REM -- gray with alpha-channel
+pnm2png.exe -alpha basn6a08.pgm basn4a08.pgm basn4a08.png
+pnm2png.exe -alpha basn6a16.pgm basn4a16.pgm basn4a16.png
+REM -- color with alpha-channel
+pnm2png.exe -alpha basn6a08.pgm basn6a08.ppm basn6a08.png
+pnm2png.exe -alpha basn6a16.pgm basn6a16.ppm basn6a16.png
+REM -- grayscale
+pnm2png.exe rawn0g01.pgm rawn0g01.png
+pnm2png.exe rawn0g02.pgm rawn0g02.png
+pnm2png.exe rawn0g04.pgm rawn0g04.png
+pnm2png.exe rawn0g08.pgm rawn0g08.png
+pnm2png.exe rawn0g16.pgm rawn0g16.png
+REM -- full-color
+pnm2png.exe rawn2c08.ppm rawn2c08.png
+pnm2png.exe rawn2c16.ppm rawn2c16.png
+REM -- palletted
+pnm2png.exe rawn3p01.ppm rawn3p01.png
+pnm2png.exe rawn3p02.ppm rawn3p02.png
+pnm2png.exe rawn3p04.ppm rawn3p04.png
+pnm2png.exe rawn3p08.ppm rawn3p08.png
+REM -- gray with alpha-channel
+pnm2png.exe -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png
+pnm2png.exe -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png
+REM -- color with alpha-channel
+pnm2png.exe -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png
+pnm2png.exe -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png
+

contrib/pngminus/pnm2png.c

@@ -0,0 +1,527 @@
+/*
+ *  pnm2png.c --- conversion from PBM/PGM/PPM-file to PNG-file
+ *  copyright (C) 1999 by Willem van Schaik <willem@schaik.com>
+ *
+ *  version 1.0 - 1999.10.15 - First version.
+ *
+ *  Permission to use, copy, modify, and distribute this software and
+ *  its documentation for any purpose and without fee is hereby granted,
+ *  provided that the above copyright notice appear in all copies and
+ *  that both that copyright notice and this permission notice appear in
+ *  supporting documentation. This software is provided "as is" without
+ *  express or implied warranty.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef __TURBOC__
+#include <mem.h>
+#include <fcntl.h>
+#endif
+
+#ifndef BOOL
+#define BOOL unsigned char
+#endif
+#ifndef TRUE
+#define TRUE (BOOL) 1
+#endif
+#ifndef FALSE
+#define FALSE (BOOL) 0
+#endif
+
+#define STDIN  0
+#define STDOUT 1
+#define STDERR 2
+
+/* to make pnm2png verbose so we can find problems (needs to be before png.h) */
+#ifndef PNG_DEBUG
+#define PNG_DEBUG 0
+#endif
+
+#include "png.h"
+
+/* function prototypes */
+
+int  main (int argc, char *argv[]);
+void usage ();
+BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha);
+void get_token(FILE *pnm_file, char *token);
+png_uint_32 get_data (FILE *pnm_file, int depth);
+png_uint_32 get_value (FILE *pnm_file, int depth);
+
+/*
+ *  main
+ */
+
+int main(int argc, char *argv[])
+{
+  FILE *fp_rd = stdin;
+  FILE *fp_al = NULL;
+  FILE *fp_wr = stdout;
+  BOOL interlace = FALSE;
+  BOOL alpha = FALSE;
+  int argi;
+
+  for (argi = 1; argi < argc; argi++)
+  {
+    if (argv[argi][0] == '-') 
+    {
+      switch (argv[argi][1]) 
+      {
+        case 'i':
+          interlace = TRUE;
+          break;
+        case 'a':
+          alpha = TRUE;
+          argi++;
+          if ((fp_al = fopen (argv[argi], "rb")) == NULL)
+          {
+            fprintf (stderr, "PNM2PNG\n");
+            fprintf (stderr, "Error:  alpha-channel file %s does not exist\n", argv[argi]);
+            exit (1);
+          }
+          break;
+        case 'h':
+        case '?':
+          usage();
+          exit(0);
+          break;
+        default:
+          fprintf (stderr, "PNM2PNG\n");
+          fprintf (stderr, "Error:  unknown option %s\n", argv[argi]);
+          usage();
+          exit(1);
+          break;
+      } /* end switch */
+    }
+    else if (fp_rd == stdin)
+    {
+      if ((fp_rd = fopen (argv[argi], "rb")) == NULL)
+      {
+        fprintf (stderr, "PNM2PNG\n");
+        fprintf (stderr, "Error:  file %s does not exist\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else if (fp_wr == stdout)
+    {
+      if ((fp_wr = fopen (argv[argi], "wb")) == NULL)
+      {
+        fprintf (stderr, "PNM2PNG\n");
+        fprintf (stderr, "Error:  can not create PNG-file %s\n", argv[argi]);
+        exit (1);
+      }
+    }
+    else
+    {
+      fprintf (stderr, "PNM2PNG\n");
+      fprintf (stderr, "Error:  too many parameters\n");
+      usage();
+      exit (1);
+    }
+  } /* end for */
+
+#ifdef __TURBOC__
+  /* set stdin/stdout to binary, we're reading the PNM always! in binary format */
+  if (fp_rd == stdin)
+  {
+    setmode (STDIN, O_BINARY);
+  }
+  if (fp_wr == stdout)
+  {
+    setmode (STDOUT, O_BINARY);
+  }
+#endif
+
+  /* call the conversion program itself */
+  if (pnm2png (fp_rd, fp_wr, fp_al, interlace, alpha) == FALSE)
+  {
+    fprintf (stderr, "PNM2PNG\n");
+    fprintf (stderr, "Error:  unsuccessful converting to PNG-image\n");
+    exit (1);
+  }
+
+  /* close input file */
+  fclose (fp_rd);
+  /* close output file */
+  fclose (fp_wr);
+  /* close alpha file */
+  if (alpha)
+    fclose (fp_al);
+
+  return 0;
+}
+
+/*
+ *  usage
+ */
+
+void usage()
+{
+  fprintf (stderr, "PNM2PNG\n");
+  fprintf (stderr, "   by Willem van Schaik, 1999\n");
+#ifdef __TURBOC__
+  fprintf (stderr, "   for Turbo-C and Borland-C compilers\n");
+#else
+  fprintf (stderr, "   for Linux (and Unix) compilers\n");
+#endif
+  fprintf (stderr, "Usage:  pnm2png [options] <file>.<pnm> [<file>.png]\n");
+  fprintf (stderr, "   or:  ... | pnm2png [options]\n");
+  fprintf (stderr, "Options:\n");
+  fprintf (stderr, "   -i[nterlace]   write png-file with interlacing on\n");
+  fprintf (stderr, "   -a[lpha] <file>.pgm read PNG alpha channel as pgm-file\n");
+  fprintf (stderr, "   -h | -?  print this help-information\n");
+}
+
+/*
+ *  pnm2png
+ */
+
+BOOL pnm2png (FILE *pnm_file, FILE *png_file, FILE *alpha_file, BOOL interlace, BOOL alpha)
+{
+  png_struct    *png_ptr = NULL;
+  png_info      *info_ptr = NULL;
+  png_byte      *png_pixels = NULL;
+  png_byte      **row_pointers = NULL;
+  png_byte      *pix_ptr = NULL;
+  png_uint_32   row_bytes;
+
+  char          type_token[16];
+  char          width_token[16];
+  char          height_token[16];
+  char          maxval_token[16];
+  int           color_type;
+  png_uint_32   width, alpha_width;
+  png_uint_32   height, alpha_height;
+  png_uint_32   maxval;
+  int           bit_depth = 0;
+  int           channels;
+  int           alpha_depth = 0;
+  int           alpha_present;
+  int           row, col;
+  BOOL          raw, alpha_raw = FALSE;
+  png_uint_32   tmp16;
+  int           i;
+
+  /* read header of PNM file */
+
+  get_token(pnm_file, type_token);
+  if (type_token[0] != 'P')
+  {
+    return FALSE;
+  }
+  else if ((type_token[1] == '1') || (type_token[1] == '4'))
+  {
+    raw = (type_token[1] == '4');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    bit_depth = 1;
+  }
+  else if ((type_token[1] == '2') || (type_token[1] == '5'))
+  {
+    raw = (type_token[1] == '5');
+    color_type = PNG_COLOR_TYPE_GRAY;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &width);
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &height);
+    get_token(pnm_file, maxval_token);
+    sscanf (maxval_token, "%lu", &maxval);
+    if (maxval <= 1)
+      bit_depth = 1;
+    else if (maxval <= 3)
+      bit_depth = 2;
+    else if (maxval <= 15)
+      bit_depth = 4;
+    else if (maxval <= 255)
+      bit_depth = 8;
+    else /* if (maxval <= 65535) */
+      bit_depth = 16;
+  }
+  else if ((type_token[1] == '3') || (type_token[1] == '6'))
+  {
+    raw = (type_token[1] == '6');
+    color_type = PNG_COLOR_TYPE_RGB;
+    get_token(pnm_file, width_token);
+    sscanf (width_token, "%lu", &width);
+    get_token(pnm_file, height_token);
+    sscanf (height_token, "%lu", &height);
+    get_token(pnm_file, maxval_token);
+    sscanf (maxval_token, "%lu", &maxval);
+    if (maxval <= 1)
+      bit_depth = 1;
+    else if (maxval <= 3)
+      bit_depth = 2;
+    else if (maxval <= 15)
+      bit_depth = 4;
+    else if (maxval <= 255)
+      bit_depth = 8;
+    else /* if (maxval <= 65535) */
+      bit_depth = 16;
+  }
+  else
+  {
+    return FALSE;
+  }
+
+  /* read header of PGM file with alpha channel */
+
+  if (alpha)
+  {
+    if (color_type == PNG_COLOR_TYPE_GRAY)
+      color_type = PNG_COLOR_TYPE_GRAY_ALPHA;
+    if (color_type == PNG_COLOR_TYPE_RGB)
+      color_type = PNG_COLOR_TYPE_RGB_ALPHA;
+
+    get_token(alpha_file, type_token);
+    if (type_token[0] != 'P')
+    {
+      return FALSE;
+    }
+    else if ((type_token[1] == '2') || (type_token[1] == '5'))
+    {
+      alpha_raw = (type_token[1] == '5');
+      get_token(alpha_file, width_token);
+      sscanf (width_token, "%lu", &alpha_width);
+      if (alpha_width != width)
+        return FALSE;
+      get_token(alpha_file, height_token);
+      sscanf (height_token, "%lu", &alpha_height);
+      if (alpha_height != height)
+        return FALSE;
+      get_token(alpha_file, maxval_token);
+      sscanf (maxval_token, "%lu", &maxval);
+      if (maxval <= 1)
+        alpha_depth = 1;
+      else if (maxval <= 3)
+        alpha_depth = 2;
+      else if (maxval <= 15)
+        alpha_depth = 4;
+      else if (maxval <= 255)
+        alpha_depth = 8;
+      else /* if (maxval <= 65535) */
+        alpha_depth = 16;
+      if (alpha_depth != bit_depth)
+        return FALSE;
+    }
+    else
+    {
+      return FALSE;
+    }
+  } /* end if alpha */
+
+  /* calculate the number of channels and store alpha-presence */
+  if (color_type == PNG_COLOR_TYPE_GRAY)
+    channels = 1;
+  else if (color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+    channels = 2;
+  else if (color_type == PNG_COLOR_TYPE_RGB)
+    channels = 3;
+  else if (color_type == PNG_COLOR_TYPE_RGB_ALPHA)
+    channels = 4;
+  else
+    channels = 0; /* should not happen */
+
+  alpha_present = (channels - 1) % 2;
+
+  /* row_bytes is the width x number of channels x (bit-depth / 8) */
+  row_bytes = width * channels * ((bit_depth <= 8) ? 1 : 2);
+
+  if ((png_pixels = (png_byte *) malloc (row_bytes * height * sizeof (png_byte))) == NULL)
+    return FALSE;
+
+  /* read data from PNM file */
+  pix_ptr = png_pixels;
+
+  for (row = 0; row < height; row++)
+  {
+    for (col = 0; col < width; col++)
+    {
+      for (i = 0; i < (channels - alpha_present); i++)
+      {
+        if (raw)
+          *pix_ptr++ = get_data (pnm_file, bit_depth);
+        else
+          if (bit_depth <= 8)
+            *pix_ptr++ = get_value (pnm_file, bit_depth);
+          else
+          {
+            tmp16 = get_value (pnm_file, bit_depth);
+            *pix_ptr = (png_byte) ((tmp16 >> 8) & 0xFF);
+            pix_ptr++;
+            *pix_ptr = (png_byte) (tmp16 & 0xFF);
+            pix_ptr++;
+          }
+      }
+
+      if (alpha) /* read alpha-channel from pgm file */
+      {
+        if (alpha_raw)
+          *pix_ptr++ = get_data (alpha_file, alpha_depth);
+        else
+          if (alpha_depth <= 8)
+            *pix_ptr++ = get_value (alpha_file, bit_depth);
+          else
+          {
+            tmp16 = get_value (alpha_file, bit_depth);
+            *pix_ptr++ = (png_byte) ((tmp16 >> 8) & 0xFF);
+            *pix_ptr++ = (png_byte) (tmp16 & 0xFF);
+          }
+      } /* if alpha */
+
+    } /* end for col */
+  } /* end for row */
+
+  /* prepare the standard PNG structures */
+  png_ptr = png_create_write_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+  if (!png_ptr)
+  {
+    return FALSE;
+  }
+  info_ptr = png_create_info_struct (png_ptr);
+  if (!info_ptr)
+  {
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+    return FALSE;
+  }
+
+  /* setjmp() must be called in every function that calls a PNG-reading libpng function */
+  if (setjmp (png_ptr->jmpbuf))
+  {
+    png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+    return FALSE;
+  }
+
+  /* initialize the png structure */
+  png_init_io (png_ptr, png_file);
+
+  /* we're going to write more or less the same PNG as the input file */
+  png_set_IHDR (png_ptr, info_ptr, width, height, bit_depth, color_type,
+    (!interlace) ? PNG_INTERLACE_NONE : PNG_INTERLACE_ADAM7,
+    PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+  /* write the file header information */
+  png_write_info (png_ptr, info_ptr);
+
+  /* if needed we will allocate memory for an new array of row-pointers */
+  if (row_pointers == (unsigned char**) NULL)
+  {
+    if ((row_pointers = (png_byte **) malloc (height * sizeof (png_bytep))) == NULL) 
+    {
+      png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+      return FALSE;
+    }
+  }
+
+  /* set the individual row_pointers to point at the correct offsets */
+  for (i = 0; i < (height); i++)
+    row_pointers[i] = png_pixels + i * row_bytes;
+
+  /* write out the entire image data in one call */
+  png_write_image (png_ptr, row_pointers);
+    
+  /* write the additional chuncks to the PNG file (not really needed) */
+  png_write_end (png_ptr, info_ptr);
+    
+  /* clean up after the write, and free any memory allocated */    
+  png_destroy_write_struct (&png_ptr, (png_infopp) NULL);
+        
+  if (row_pointers != (unsigned char**) NULL)
+    free (row_pointers);
+  if (png_pixels != (unsigned char*) NULL)
+    free (png_pixels);
+
+  return TRUE;
+} /* end of pnm2png */
+
+/*
+ * get_token() - gets the first string after whitespace
+ */
+
+void get_token(FILE *pnm_file, char *token)
+{
+  int i = 0;
+
+  /* remove white-space */
+  do
+  {
+    token[i] = (unsigned char) fgetc (pnm_file);
+  }
+  while ((token[i] == '\n') || (token[i] == '\r') || (token[i] == ' '));
+
+  /* read string */
+  do
+  {
+    i++;
+    token[i] = (unsigned char) fgetc (pnm_file);
+  }
+  while ((token[i] != '\n') && (token[i] != '\r') && (token[i] != ' '));
+
+  token[i] = '\0';
+
+  return;
+}
+
+/*
+ * get_data() - takes first byte and converts into next pixel value,
+ *        taking as much bits as defined by bit-depth and
+ *        using the bit-depth to fill up a byte (0Ah -> AAh)
+ */
+
+png_uint_32 get_data (FILE *pnm_file, int depth)
+{
+  static int bits_left = 0;
+  static int old_value = 0;
+  static int mask = 0;
+  int i;
+  png_uint_32 ret_value;
+
+  if (mask == 0)
+    for (i = 0; i < depth; i++)
+      mask = (mask >> 1) | 0x80;
+
+  if (bits_left <= 0)
+  {
+    old_value = fgetc (pnm_file);
+    bits_left = 8;
+  }
+
+  ret_value = old_value & mask;
+  for (i = 1; i < (8 / depth); i++)
+    ret_value = ret_value || (ret_value >> depth);
+
+  old_value = (old_value << depth) & 0xFF;
+  bits_left -= depth;
+
+  return ret_value;
+}
+
+/*
+ * get_value() - takes first (numeric) string and converts into number,
+ *         using the bit-depth to fill up a byte (0Ah -> AAh)
+ */
+
+png_uint_32 get_value (FILE *pnm_file, int depth)
+{
+  static png_uint_32 mask = 0;
+  png_byte token[16];
+  png_uint_32 ret_value;
+  int i = 0;
+
+  if (mask == 0)
+    for (i = 0; i < depth; i++)
+      mask = (mask << 1) | 0x01;
+
+  get_token (pnm_file, token);
+  sscanf (token, "%lu", &ret_value);
+
+  ret_value &= mask;
+
+  if (depth < 8)
+    for (i = 0; i < (8 / depth); i++)
+      ret_value = (ret_value << depth) || ret_value;
+
+  return ret_value;
+}
+
+/* end of source */
+

contrib/pngminus/pnm2png.sh

@@ -0,0 +1,41 @@
+# -- grayscale
+./pnm2png basn0g01.pgm basn0g01.png
+./pnm2png basn0g02.pgm basn0g02.png
+./pnm2png basn0g04.pgm basn0g04.png
+./pnm2png basn0g08.pgm basn0g08.png
+./pnm2png basn0g16.pgm basn0g16.png
+# -- full-color
+./pnm2png basn2c08.ppm basn2c08.png
+./pnm2png basn2c16.ppm basn2c16.png
+# -- palletted
+./pnm2png basn3p01.ppm basn3p01.png
+./pnm2png basn3p02.ppm basn3p02.png
+./pnm2png basn3p04.ppm basn3p04.png
+./pnm2png basn3p08.ppm basn3p08.png
+# -- gray with alpha-channel
+./pnm2png -alpha basn6a08.pgm basn4a08.pgm basn4a08.png
+./pnm2png -alpha basn6a16.pgm basn4a16.pgm basn4a16.png
+# -- color with alpha-channel
+./pnm2png -alpha basn6a08.pgm basn6a08.ppm basn6a08.png
+./pnm2png -alpha basn6a16.pgm basn6a16.ppm basn6a16.png
+# -- grayscale
+./pnm2png rawn0g01.pgm rawn0g01.png
+./pnm2png rawn0g02.pgm rawn0g02.png
+./pnm2png rawn0g04.pgm rawn0g04.png
+./pnm2png rawn0g08.pgm rawn0g08.png
+./pnm2png rawn0g16.pgm rawn0g16.png
+# -- full-color
+./pnm2png rawn2c08.ppm rawn2c08.png
+./pnm2png rawn2c16.ppm rawn2c16.png
+# -- palletted
+./pnm2png rawn3p01.ppm rawn3p01.png
+./pnm2png rawn3p02.ppm rawn3p02.png
+./pnm2png rawn3p04.ppm rawn3p04.png
+./pnm2png rawn3p08.ppm rawn3p08.png
+# -- gray with alpha-channel
+./pnm2png -alpha rawn6a08.pgm rawn4a08.pgm rawn4a08.png
+./pnm2png -alpha rawn6a16.pgm rawn4a16.pgm rawn4a16.png
+# -- color with alpha-channel
+./pnm2png -alpha rawn6a08.pgm rawn6a08.ppm rawn6a08.png
+./pnm2png -alpha rawn6a16.pgm rawn6a16.ppm rawn6a16.png
+

contrib/pngsuite/README

@@ -0,0 +1,85 @@
+
+pngsuite
+--------
+(c) Willem van Schaik, 1999
+
+Permission to use, copy, and distribute these images for any purpose and
+without fee is hereby granted.
+
+These 15 images are part of the much larger PngSuite test-set of 
+images, available for developers of PNG supporting software. The 
+complete set, available at http:/www.schaik.com/pngsuite/, contains 
+a variety of images to test interlacing, gamma settings, ancillary
+chunks, etc.
+
+The images in this directory represent the basic PNG color-types:
+grayscale (1-16 bit deep), full color (8 or 16 bit), paletted
+(1-8 bit) and grayscale or color images with alpha channel. You
+can use them to test the proper functioning of PNG software.
+
+    filename      depth type
+    ------------ ------ --------------
+    basn0g01.png  1-bit grayscale
+    basn0g02.png  2-bit grayscale
+    basn0g04.png  4-bit grayscale
+    basn0g08.png  8-bit grayscale
+    basn0g16.png 16-bit grayscale
+    basn2c08.png  8-bit truecolor
+    basn2c16.png 16-bit truecolor
+    basn3p01.png  1-bit paletted
+    basn3p02.png  2-bit paletted
+    basn3p04.png  4-bit paletted
+    basn3p08.png  8-bit paletted
+    basn4a08.png  8-bit gray with alpha
+    basn4a16.png 16-bit gray with alpha
+    basn6a08.png  8-bit RGBA
+    basn6a16.png 16-bit RGBA
+
+Here is the correct result of typing "pngtest -m *.png" in
+this directory:
+
+Testing basn0g01.png: PASS (524 zero samples)
+ Filter 0 was used 32 times
+Testing basn0g02.png: PASS (448 zero samples)
+ Filter 0 was used 32 times
+Testing basn0g04.png: PASS (520 zero samples)
+ Filter 0 was used 32 times
+Testing basn0g08.png: PASS (3 zero samples)
+ Filter 1 was used 9 times
+ Filter 4 was used 23 times
+Testing basn0g16.png: PASS (1 zero samples)
+ Filter 1 was used 1 times
+ Filter 2 was used 31 times
+Testing basn2c08.png: PASS (6 zero samples)
+ Filter 1 was used 5 times
+ Filter 4 was used 27 times
+Testing basn2c16.png: PASS (592 zero samples)
+ Filter 1 was used 1 times
+ Filter 4 was used 31 times
+Testing basn3p01.png: PASS (512 zero samples)
+ Filter 0 was used 32 times
+Testing basn3p02.png: PASS (448 zero samples)
+ Filter 0 was used 32 times
+Testing basn3p04.png: PASS (544 zero samples)
+ Filter 0 was used 32 times
+Testing basn3p08.png: PASS (4 zero samples)
+ Filter 0 was used 32 times
+Testing basn4a08.png: PASS (32 zero samples)
+ Filter 1 was used 1 times
+ Filter 4 was used 31 times
+Testing basn4a16.png: PASS (64 zero samples)
+ Filter 0 was used 1 times
+ Filter 1 was used 2 times
+ Filter 2 was used 1 times
+ Filter 4 was used 28 times
+Testing basn6a08.png: PASS (160 zero samples)
+ Filter 1 was used 1 times
+ Filter 4 was used 31 times
+Testing basn6a16.png: PASS (1072 zero samples)
+ Filter 1 was used 4 times
+ Filter 4 was used 28 times
+libpng passes test
+
+Willem van Schaik
+<willem@schaik.com>
+October 1999

example.c

@@ -1,4 +1,6 @@
 
+#if 0 /* in case someone actually tries to compile this */
+
 /* example.c - an example of using libpng */
 
 /* This is an example of how to use libpng to read and write PNG files.
@@ -15,8 +17,11 @@
 
 #include "png.h"
 
-/* Check to see if a file is a PNG file using png_sig_cmp().  Returns
- * non-zero if the image is a PNG, and 0 if it isn't a PNG.
+/* 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
@@ -41,12 +46,14 @@ int check_if_png(char *file_name, FILE **fp)
    if ((*fp = fopen(file_name, "rb")) != NULL);
       return 0;
 
-   /* Read in the signature bytes */
+   /* Read in some of the signature bytes */
    if (fread(buf, 1, PNG_BYTES_TO_CHECK, *fp) != PNG_BYTES_TO_CHECK)
       return 0;
 
-   /* Compare the first PNG_BYTES_TO_CHECK bytes of the signature. */
-   return(png_sig_cmp(buf, (png_size_t)0, PNG_BYTES_TO_CHECK));
+   /* 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
@@ -146,7 +153,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
    /* 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 th
+   /* Strip alpha bytes from the input data without combining with the
     * background (not recommended).
     */
    png_set_strip_alpha(png_ptr);
@@ -192,7 +199,8 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
 
    /* Some suggestions as to how to get a screen gamma value */
 
-   /* Note that screen gamma is (display_gamma/viewing_gamma) */
+   /* Note that screen gamma is the display_exponent, which includes
+    * the CRT_exponent and any correction for viewing conditions */
    if (/* We have a user-defined screen gamma value */)
    {
       screen_gamma = user-defined screen_gamma;
@@ -219,7 +227,7 @@ void read_png(FILE *fp, unsigned int sig_read)  /* file is already open */
    int intent;
 
    if (png_get_sRGB(png_ptr, info_ptr, &intent))
-      png_set_sRGB(png_ptr, intent, 0);
+      png_set_sRGB(png_ptr, info_ptr, intent);
    else
    {
       double image_gamma;
@@ -596,6 +604,14 @@ void write_png(char *file_name /* , ... other image information ... */)
    /* Write the file header information.  REQUIRED */
    png_write_info(png_ptr, info_ptr);
 
+   /* If you want, you can write the info in two steps, in case you need to
+    * write your private chunk ahead of PLTE:
+    *
+    *   png_write_info_before_PLTE(write_ptr, write_info_ptr);
+    *   write_my_chunk();
+    *   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
@@ -695,3 +711,4 @@ void write_png(char *file_name /* , ... other image information ... */)
    return;
 }
 
+#endif /* if 0 */

libpng.txt

@@ -1,9 +1,9 @@
 libpng.txt - A description on how to use and modify libpng
 
- libpng version 1.0.2a - December 29, 1998
+ libpng version 1.0.5d - November 29, 1999
  Updated and distributed by Glenn Randers-Pehrson
- <randeg@alumni.rpi.edu>
- Copyright (c) 1998, Glenn Randers-Pehrson
+ <randeg@alum.rpi.edu>
+ Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  For conditions of distribution and use, see copyright
  notice in png.h.
 
@@ -22,6 +22,7 @@ libpng.txt - A description on how to use and modify libpng
  Copyright (c) 1995 Frank J. T. Wojcik
  December 18, 1995 && January 20, 1996
 
+ *
 I. Introduction
 
 This file describes how to use and modify the PNG reference library
@@ -35,11 +36,17 @@ INSTALL file for instructions on how to install libpng.
 
 Libpng was written as a companion to the PNG specification, as a way
 of reducing the amount of time and effort it takes to support the PNG
-file format in application programs.  The PNG specification is available
+file format in application programs.
+
+The PNG-1.2 specification is available at <http://www.cdrom.com/png>.
+
+The PNG-1.0 specification is available
 as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/> and as a
 W3C Recommendation <http://www.w3.org/TR/REC.png.html>. Some
 additional chunks are described in the special-purpose public chunks
-documents at <ftp://ftp.uu.net/graphics/png/documents/>.  Other information
+documents at <ftp://ftp.uu.net/graphics/png/documents/>.
+
+Other information
 about PNG, and the latest version of libpng, can be found at the PNG home
 page, <http://www.cdrom.com/pub/png/>.
 
@@ -129,7 +136,7 @@ Customizing libpng.
         return;
     }
     fread(header, 1, number, fp);
-    is_png = png_check_sig(header, 0, number);
+    is_png = !png_sig_cmp(header, 0, number);
     if (!is_png)
     {
         return;
@@ -222,7 +229,7 @@ called after each row has been read, which you can use to control
 a progress meter or the like.  It's demonstrated in pngtest.c.
 You must supply a function
 
-    void read_row_callback(png_ptr, png_uint_32 row, int pass);
+    void read_row_callback(png_ptr ptr, png_uint_32 row, int pass);
     {
       /* put your code here */
     }
@@ -261,6 +268,21 @@ You must supply the function
 See pngtest.c for a working example.  Your function will be called
 after all of the other transformations have been processed.
 
+You can also set up a pointer to a user structure for use by your
+callback function, and you can inform libpng that your transform
+function will change the number of channels or bit depth with the
+function
+
+    png_set_user_transform_info(png_ptr, user_ptr,
+       user_depth, user_channels);
+
+
+You can retrieve the pointer via the function
+png_get_user_transform_ptr().  For example:
+
+    voidp read_user_transform_ptr =
+       png_get_user_transform_ptr(png_ptr);
+
 You are now ready to read all the file information up to the actual
 image data.  You do this with a call to png_read_info().
 
@@ -506,13 +528,18 @@ grayscale images with bit depths of 2 or 4 or if there is a multiple-image
 viewing application that wishes to treat all images in the same way.
 
     if (color_type == PNG_COLOR_TYPE_PALETTE &&
-        bit_depth <= 8) png_set_expand(png_ptr);
+        bit_depth <= 8) png_set_palette_to_rgb(png_ptr);
 
     if (color_type == PNG_COLOR_TYPE_GRAY &&
-        bit_depth < 8) png_set_expand(png_ptr);
+        bit_depth < 8) png_set_gray_1_2_4_to_8(png_ptr);
 
     if (png_get_valid(png_ptr, info_ptr,
-        PNG_INFO_tRNS)) png_set_expand(png_ptr);
+        PNG_INFO_tRNS)) png_set_tRNS_to_alpha(png_ptr);
+
+These three functions are actually aliases for png_set_expand(), added
+in libpng version 1.0.4, with the function names expanded to improve code
+readability.  In some future version they may actually do different
+things.
 
 PNG can have files with 16 bits per channel.  If you only can handle
 8 bits per channel, this will strip the pixels down to 8 bit.
@@ -599,7 +626,7 @@ and blue channels, leaving the green channel in the gray position.
     if (color_type == PNG_COLOR_TYPE_RGB ||
         color_type == PNG_COLOR_TYPE_RGB_ALPHA)
           png_set_rgb_to_gray(png_ptr, error_action,
-             float red_weight, float green_weight);
+             double red_weight, double green_weight);
 
     error_action = 1: silently do the conversion
     error_action = 2: issue a warning if the original
@@ -648,7 +675,8 @@ which can be expressed with integers as
 The calculation is done in a linear colorspace, if the image gamma
 is known.
 
-If you have a grayscale and you are using png_set_expand() to change to
+If you have a grayscale and you are using png_set_expand_depth() or
+png_set_expand() to change to
 a higher bit-depth, you must either supply the background color as a gray
 value at the original file bit-depth (need_expand = 1) or else supply the
 background color as an RGB triplet at the final, expanded bit depth
@@ -669,17 +697,17 @@ or as an RGB triplet that may or may not be in the palette (need_expand = 0).
 To properly display PNG images on any kind of system, the application needs
 to know what the display gamma is.  Ideally, the user will know this, and
 the application will allow them to set it.  One method of allowing the user
-to set the display gamma separately for each system is to check for the
-DISPLAY_GAMMA and VIEWING_GAMMA environment variables or for a SCREEN_GAMMA
-environment variable, which will hopefully be correctly set.
+to set the display gamma separately for each system is to check for a
+SCREEN_GAMMA or DISPLAY_GAMMA environment variable, which will hopefully be
+correctly set.
 
-Note that display_gamma is the gamma of your display, while screen_gamma is
-the overall gamma correction required to produce pleasing results,
-which depends on the lighting conditions in the surrounding environment.
-Screen_gamma is display_gamma/viewing_gamma, where viewing_gamma is
-the amount of additional gamma correction needed to compensate for
-a (viewing_gamma=1.25) environment.  In a dim or brightly lit room, no
-compensation other than the display_gamma is needed (viewing_gamma=1.0).
+Note that display_gamma is the overall gamma correction required to produce
+pleasing results, which depends on the lighting conditions in the surrounding
+environment.  In a dim or brightly lit room, no compensation other than
+the physical gamma exponent of the monitor is needed, while in a dark room
+a slightly smaller exponent is better.
+
+   double gamma, screen_gamma;
 
    if (/* We have a user-defined screen
        gamma value */)
@@ -691,7 +719,7 @@ compensation other than the display_gamma is needed (viewing_gamma=1.0).
    else if ((gamma_str = getenv("SCREEN_GAMMA"))
       != NULL)
    {
-      screen_gamma = atof(gamma_str);
+      screen_gamma = (double)atof(gamma_str);
    }
    /* If we don't have another value */
    else
@@ -831,7 +859,7 @@ row_pointers:
     png_read_row(png_ptr, &row_pointers, NULL);
 
 If the file is interlaced (info_ptr->interlace_type != 0), things get
-somewhat harder.  The only current (PNG Specification version 1.0)
+somewhat harder.  The only current (PNG Specification version 1.2)
 interlacing type for PNG is (interlace_type == PNG_INTERLACE_ADAM7)
 is a somewhat complicated 2D interlace scheme, known as Adam7, that
 breaks down an image into seven smaller images of varying size, based
@@ -1194,7 +1222,7 @@ have no special needs in this area, let the library do what it wants by
 not calling this function at all, as it has been tuned to deliver a good
 speed/compression ratio. The second parameter to png_set_filter() is
 the filter method, for which the only valid value is '0' (as of the
-October 1996 PNG specification, version 1.0).  The third parameter is a
+July 1999 PNG specification, version 1.2).  The third parameter is a
 flag that indicates which filter type(s) are to be tested for each
 scanline.  See the Compression Library for details on the specific filter
 types.
@@ -1226,7 +1254,7 @@ data.  See the Compression Library for details on the compression levels.
 You now need to fill in the png_info structure with all the data you
 wish to write before the actual image.  Note that the only thing you
 are allowed to write after the image is the text chunks and the time
-chunk (as of PNG Specification 1.0, anyway).  See png_write_end() and
+chunk (as of PNG Specification 1.2, anyway).  See png_write_end() and
 the latest PNG specification for more information on that.  If you
 wish to write them before the image, fill them in now, and flag that
 data as being valid.  If you want to wait until after the data, don't
@@ -1294,10 +1322,10 @@ Some of the more important parts of the png_info are:
                      Color Consortium
                      (http://www.color.org).
                      It can be one of
-                     PNG_SRGB_INTENT_SATURATION,
-                     PNG_SRGB_INTENT_PERCEPTUAL,
-                     PNG_SRGB_INTENT_ABSOLUTE, or
-                     PNG_SRGB_INTENT_RELATIVE.
+                     PNG_sRGB_INTENT_SATURATION,
+                     PNG_sRGB_INTENT_PERCEPTUAL,
+                     PNG_sRGB_INTENT_ABSOLUTE, or
+                     PNG_sRGB_INTENT_RELATIVE.
 
 
     png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr,
@@ -1461,6 +1489,14 @@ image data.  You do this with a call to png_write_info().
 
     png_write_info(png_ptr, info_ptr);
 
+If you need to write a private chunk that you want to appear before
+the PLTE chunk when PLTE is present, you can write the PNG info in
+two steps, and insert code to write your own chunk between them:
+
+    png_write_info_before_PLTE(png_ptr, info_ptr);
+    write_my_private_chunks();
+    png_write_info(png_ptr, info_ptr);
+
 After you've written the file information, you can set up the library
 to handle any special transformations of the image data.  The various
 ways to transform the data will be described in the order that they
@@ -1555,7 +1591,21 @@ You must supply the function
        row_info, png_bytep data)
 
 See pngtest.c for a working example.  Your function will be called
-before any of the other transformations have been processed.
+before any of the other transformations are processed.
+
+You can also set up a pointer to a user structure for use by your
+callback function.
+
+    png_set_user_transform_info(png_ptr, user_ptr, 0, 0);
+
+The user_channels and user_depth parameters of this function are ignored
+when writing; you can set them to zero as shown.
+
+You can retrieve the pointer via the function
+png_get_user_transform_ptr().  For example:
+
+    voidp write_user_transform_ptr =
+       png_get_user_transform_ptr(png_ptr);
 
 It is possible to have libpng flush any pending output, either manually,
 or automatically after a certain number of lines have been written.  To
@@ -1612,8 +1662,8 @@ row_pointers:
     png_write_row(png_ptr, &row_pointer);
 
 When the file is interlaced, things can get a good deal more
-complicated.  The only currently (as of February 1998 -- PNG Specification
-version 1.0, dated October 1996) defined interlacing scheme for PNG files
+complicated.  The only currently (as of August 1999 -- PNG Specification
+version 1.2, dated July 1999) defined interlacing scheme for PNG files
 is the "Adam7" interlace scheme, that breaks down an
 image into seven smaller images of varying size.  libpng will build
 these images for you, or you can do them yourself.  If you want to
@@ -1658,7 +1708,6 @@ palette, or histogram, before the call to png_destroy_write_struct();
 
 For a more compact example of writing a PNG image, see the file example.c.
 
-
 V. Modifying/Customizing libpng:
 
 There are two issues here.  The first is changing how libpng does
@@ -1685,7 +1734,8 @@ which currently just call fread() and fwrite().  The FILE * is stored in
 png_struct and is initialized via png_init_io().  If you wish to change
 the method of I/O, the library supplies callbacks that you can set
 through the function png_set_read_fn() and png_set_write_fn() at run
-time, instead of calling the png_init_io() function.  These functions
+time, instead of calling the png_init_io() function.
+These functions
 also provide a void pointer that can be retrieved via the function
 png_get_io_ptr().  For example:
 
@@ -1755,7 +1805,7 @@ a first level of understanding of how it works.  Pay particular attention
 to the sections that describe chunk names, and look at how other chunks
 were designed, so you can do things similarly.  Second, check out the
 sections of libpng that read and write chunks.  Try to find a chunk that
-is similar to yours and copy off of it.  More details can be found in the
+is similar to yours and use it as a template.  More details can be found in the
 comments inside the code.  A way of handling unknown chunks in a generic
 method, potentially via callback functions, would be best.
 
@@ -1852,7 +1902,7 @@ images (with and without alpha), but not for paletted images nor
 for any images with bit depths less than 8 bits/pixel.
 
 The 'method' parameter sets the main filtering method, which is
-currently only '0' in the PNG 1.0 specification.  The 'filters'
+currently only '0' in the PNG 1.2 specification.  The 'filters'
 parameter sets which filter(s), if any, should be used for each
 scanline.  Possible values are PNG_ALL_FILTERS and PNG_NO_FILTERS
 to turn filtering on and off, respectively.
@@ -2013,3 +2063,58 @@ to set the error callbacks AFTER png_read_init(), or to change them with
 png_set_error_fn(), which is essentially the same function, but with a
 new name to force compilation errors with applications that try to use
 the old method.
+
+VII. Y2K Compliance in libpng
+
+November 29, 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 1.0.5d 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

libpngpf.3

@@ -1,339 +1,497 @@
-.TH LIBPNGPF 3 "December 29, 1998"
+.TH LIBPNGPF 3 November 29, 1999
 .SH NAME
-libpng \- Portable Network Graphics (PNG) Reference Library 1.0.2a - December 29, 1998
+libpng \- Portable Network Graphics (PNG) Reference Library 1.0.5d - November 29, 1999
 (private functions)
 .SH SYNOPSIS
-#include <png.h>
+\fB#include <png.h>\fP
 
-void png_build_gamma_table (png_structp png_ptr);
+\fI\fB
 
-void png_build_grayscale_palette (int bit_depth, png_colorp
-palette);
+\fBvoid png_build_gamma_table (png_structp \fIpng_ptr\fP\fB);\fP
 
-void png_calculate_crc (png_structp png_ptr, png_bytep ptr,
-png_size_t length);
-void png_check_chunk_name (png_structp png_ptr, png_bytep
-chunk_name);
+\fI\fB
 
-png_size_t png_check_keyword (png_structp png_ptr, png_charp
-key, png_charpp new_key);
+\fBvoid png_build_grayscale_palette (int \fP\fIbit_depth\fP\fB, png_colorp \fIpalette\fP\fB);\fP
 
-void png_combine_row (png_structp png_ptr, png_bytep row, int
-mask);
+\fI\fB
 
-void png_correct_palette (png_structp png_ptr, png_colorp
-palette, int num_palette);
+\fBvoid png_calculate_crc (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIptr\fP\fB, png_size_t \fIlength\fP\fB);\fP
 
-int png_crc_error (png_structp png_ptr);
+\fI\fB
 
-int png_crc_finish (png_structp png_ptr, png_uint_32 skip);
+\fBvoid png_check_chunk_name (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fIchunk_name\fP\fB);\fP
 
-void png_crc_read (png_structp png_ptr, png_bytep buf,
-png_size_t length);
+\fI\fB
 
-png_voidp png_create_struct (int type, png_malloc_ptr malloc_fn);
+\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
 
-png_voidp png_create_struct_2 (int type);
+\fI\fB
 
-void png_destroy_struct (png_voidp struct_ptr);
+\fBvoid png_combine_row (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fImask\fP\fB);\fP
 
-void png_destroy_struct_2 (png_voidp struct_ptr, png_free_ptr
-free_fn);
+\fI\fB
 
-void png_do_background (png_row_infop row_info, png_bytep row,
-png_color_16p trans_values, png_color_16p background,
-png_color_16p background_1, png_bytep gamma_table, png_bytep
-gamma_from_1, png_bytep gamma_to_1, png_uint_16pp gamma_16,
-png_uint_16pp gamma_16_from_1, png_uint_16pp gamma_16_to_1, int
-gamma_shift);
+\fBvoid png_correct_palette (png_structp \fP\fIpng_ptr\fP\fB, png_colorp \fP\fIpalette\fP\fB, int \fInum_palette\fP\fB);\fP
 
-void png_do_bgr (png_row_infop row_info, png_bytep row);
+\fI\fB
 
-void png_do_chop (png_row_infop row_info, png_bytep row);
+\fBint png_crc_error (png_structp \fIpng_ptr\fP\fB);\fP
 
-void png_do_dither (png_row_infop row_info, png_bytep row,
-png_bytep palette_lookup, png_bytep dither_lookup);
+\fI\fB
 
-void png_do_expand (png_row_infop row_info, png_bytep row,
-png_color_16p trans_value);
+\fBint png_crc_finish (png_structp \fP\fIpng_ptr\fP\fB, png_uint_32 \fIskip\fP\fB);\fP
 
-void png_do_expand_palette (png_row_infop row_info, png_bytep
-row, png_colorp palette, png_bytep trans, int num_trans);
+\fI\fB
 
-void png_do_gamma (png_row_infop row_info, png_bytep row,
-png_bytep gamma_table, png_uint_16pp gamma_16_table, int
-gamma_shift);
+\fBvoid png_crc_read (png_structp \fP\fIpng_ptr\fP\fB, png_bytep \fP\fIbuf\fP\fB, png_size_t \fIlength\fP\fB);\fP
 
-void png_do_gray_to_rgb (png_row_infop row_info, png_bytep
-row);
+\fI\fB
 
-void png_do_invert (png_row_infop row_info, png_bytep row);
+\fBpng_voidp png_create_struct (int \fP\fItype\fP\fB, png_malloc_ptr \fImalloc_fn\fP\fB);\fP
 
-void png_do_pack (png_row_infop row_info, png_bytep row,
-png_uint_32 bit_depth);
+\fI\fB
 
-void png_do_packswap (png_row_infop row_info, png_bytep row);
+\fBpng_voidp png_create_struct_2 (int \fItype\fP\fB);\fP
 
-void png_do_read_filler (png_row_infop row_info, png_bytep row,
-png_uint_32 filler, png_uint_32 flags);
+\fI\fB
 
-void png_do_read_interlace (png_row_infop row_info, png_bytep
-row, int pass, png_uint_32 transformations);
+\fBvoid png_destroy_struct (png_voidp \fIstruct_ptr\fP\fB);\fP
 
-void png_do_read_invert_alpha (png_row_infop row_info,
-png_bytep row);
+\fI\fB
 
-void png_do_read_swap_alpha (png_row_infop row_info, png_bytep
-row);
+\fBvoid png_destroy_struct_2 (png_voidp \fP\fIstruct_ptr\fP\fB, png_free_ptr \fIfree_fn\fP\fB);\fP
 
-void png_do_read_transformations (png_structp png_ptr);
+\fI\fB
 
-int png_do_rgb_to_gray (png_row_infop row_info, png_bytep
-row);
+\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
 
-void png_do_shift (png_row_infop row_info, png_bytep row,
-png_color_8p bit_depth);
+\fI\fB
 
-void png_do_strip_filler (png_row_infop row_info, png_bytep
-row, png_uint_32 flags);
+\fBvoid png_do_bgr (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_do_swap (png_row_infop row_info, png_bytep row);
+\fI\fB
 
-void png_do_unpack (png_row_infop row_info, png_bytep row);
+\fBvoid png_do_chop (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_do_unshift (png_row_infop row_info, png_bytep row,
-png_color_8p sig_bits);
+\fI\fB
 
-void png_do_write_interlace (png_row_infop row_info, png_bytep
-row, int pass);
+\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
 
-void png_do_write_invert_alpha (png_row_infop row_info,
-png_bytep row);
+\fI\fB
 
-void png_do_write_swap_alpha (png_row_infop row_info, png_bytep
-row);
+\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
 
-void png_do_write_transformations (png_structp png_ptr);
+\fI\fB
 
-void *png_far_to_near (png_structp png_ptr,png_voidp ptr,
-int check);
+\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
 
-void png_flush (png_structp png_ptr);
+\fI\fB
 
-png_int_32 png_get_int_32 (png_bytep buf);
+\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
 
-png_uint_16 png_get_uint_16 (png_bytep buf);
+\fI\fB
 
-png_uint_32 png_get_uint_32 (png_bytep buf);
+\fBvoid png_do_gray_to_rgb (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_handle_bKGD (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_cHRM (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fBvoid png_do_invert (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_handle_gAMA (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_hIST (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\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
 
-void png_handle_IEND (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_IHDR (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fBvoid png_do_packswap (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_handle_oFFs (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_pCAL (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\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
 
-void png_handle_pHYs (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_PLTE (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\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
 
-void png_handle_sBIT (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_sRGB (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fBvoid png_do_read_invert_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_handle_tEXt (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_tIME (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fBvoid png_do_read_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_handle_tRNS (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_handle_unknown (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 length);
+\fBvoid png_do_read_transformations (png_structp \fIpng_ptr\fP\fB);\fP
 
-void png_handle_zTXt (png_structp png_ptr, png_infop info_ptr,
-png_uint_32 length);
+\fI\fB
 
-void png_info_destroy (png_structp png_ptr, png_infop
-info_ptr);
+\fBint png_do_rgb_to_gray (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_init_read_transformations (png_structp png_ptr);
+\fI\fB
 
-void png_process_IDAT_data (png_structp png_ptr, png_bytep
-buffer, png_size_t buffer_length);
+\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
 
-void png_process_some_data (png_structp png_ptr, png_infop
-info_ptr);
+\fI\fB
 
-void png_push_check_crc (png_structp png_ptr);
+\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
 
-void png_push_crc_finish (png_structp png_ptr);
+\fI\fB
 
-void png_push_crc_skip (png_structp png_ptr, png_uint_32
-length);
+\fBvoid png_do_swap (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_push_fill_buffer (png_structp png_ptr, png_bytep
-buffer, png_size_t length);
+\fI\fB
 
-void png_push_handle_tEXt (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 length);
+\fBvoid png_do_unpack (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_push_handle_unknown (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 length);
+\fI\fB
 
-void png_push_handle_zTXt (png_structp png_ptr, png_infop
-info_ptr, png_uint_32 length);
+\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
 
-void png_push_have_end (png_structp png_ptr, png_infop
-info_ptr);
+\fI\fB
 
-void png_push_have_info (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_do_write_interlace (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fP\fIrow\fP\fB, int \fIpass\fP\fB);\fP
 
-void png_push_have_row (png_structp png_ptr, png_bytep row);
+\fI\fB
 
-void png_push_process_row (png_structp png_ptr);
+\fBvoid png_do_write_invert_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_push_read_chunk (png_structp png_ptr, png_infop
-info_ptr);
+\fI\fB
 
-void png_push_read_end (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_do_write_swap_alpha (png_row_infop \fP\fIrow_info\fP\fB, png_bytep \fIrow\fP\fB);\fP
 
-void png_push_read_IDAT (png_structp png_ptr);
+\fI\fB
 
-void png_push_read_sig (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid png_do_write_transformations (png_structp \fIpng_ptr\fP\fB);\fP
 
-void png_push_read_tEXt (png_structp png_ptr, png_infop
-info_ptr);
+\fI\fB
 
-void png_push_read_zTXt (png_structp png_ptr, png_infop
-info_ptr);
+\fBvoid *png_far_to_near (png_structp png_ptr,png_voidp \fP\fIptr\fP\fB, int \fIcheck\fP\fB);\fP
 
-void png_push_restore_buffer (png_structp png_ptr, png_bytep
-buffer, png_size_t buffer_length);
+\fI\fB
 
-void png_push_save_buffer (png_structp png_ptr);
+\fBvoid png_flush (png_structp \fIpng_ptr\fP\fB);\fP
 
-void png_read_data (png_structp png_ptr, png_bytep data,
-png_size_t length);
+\fI\fB
 
-void png_read_filter_row (png_structp png_ptr, png_row_infop
-row_info, png_bytep row, png_bytep prev_row, int filter);
+\fBpng_int_32 png_get_int_32 (png_bytep \fIbuf\fP\fB);\fP
 
-void png_read_finish_row (png_structp png_ptr);
+\fI\fB
 
-void png_read_init (png_structp png_ptr);
+\fBpng_uint_16 png_get_uint_16 (png_bytep \fIbuf\fP\fB);\fP
 
-void png_read_push_finish_row (png_structp png_ptr);
+\fI\fB
 
-void png_read_start_row (png_structp png_ptr);
+\fBpng_uint_32 png_get_uint_32 (png_bytep \fIbuf\fP\fB);\fP
 
-void png_read_transform_info (png_structp png_ptr, png_infop
-info_ptr);
+\fI\fB
 
-void png_reset_crc (png_structp png_ptr);
+\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
 
-void png_save_int_32 (png_bytep buf, png_int_32 i);
+\fI\fB
 
-void png_save_uint_16 (png_bytep buf, unsigned int i);
+\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
 
-void png_save_uint_32 (png_bytep buf, png_uint_32 i);
+\fI\fB
 
-void png_write_bKGD (png_structp png_ptr, png_color_16p values,
-int color_type);
+\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
 
-void png_write_cHRM (png_structp png_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);
+\fI\fB
 
-void png_write_data (png_structp png_ptr, png_bytep data,
-png_size_t length);
-void png_write_filtered_row (png_structp png_ptr, png_bytep
-filtered_row);
+\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
 
-void png_write_find_filter (png_structp png_ptr, png_row_infop
-row_info);
+\fI\fB
 
-void png_write_finish_row (png_structp png_ptr);
+\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
 
-void png_write_gAMA (png_structp png_ptr, double file_gamma);
+\fI\fB
 
-void png_write_hIST (png_structp png_ptr, png_uint_16p hist,
-int num_hist);
+\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
 
-void png_write_init (png_structp png_ptr);
+\fI\fB
 
-void png_write_IDAT (png_structp png_ptr, png_bytep data,
-png_size_t length);
+\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
 
-void png_write_IEND (png_structp png_ptr);
+\fI\fB
 
-void png_write_IHDR (png_structp png_ptr, png_uint_32 width,
-png_uint_32 height, int bit_depth, int color_type, int
-compression_type, int filter_type, int interlace_type);
+\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
 
-void png_write_oFFs (png_structp png_ptr, png_uint_32 x_offset,
-png_uint_32 y_offset, int unit_type);
+\fI\fB
 
-void png_write_pCAL (png_structp png_ptr, png_charp purpose,
-png_int_32 X0, png_int_32 X1, int type, int nparams, png_charp
-units, png_charpp params);
+\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
 
-void png_write_pHYs (png_structp png_ptr, png_uint_32
-x_pixels_per_unit, png_uint_32 y_pixels_per_unit, int
-unit_type);
+\fI\fB
 
-void png_write_PLTE (png_structp png_ptr, png_colorp palette,
-png_uint_32 num_pal);
+\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
 
-void png_write_sBIT (png_structp png_ptr, png_color_8p sbit,
-int color_type);
+\fI\fB
 
-void png_write_sig (png_structp png_ptr);
+\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
 
-void png_write_sRGB (png_structp png_ptr, int intent);
+\fI\fB
 
-void png_write_start_row (png_structp png_ptr);
+\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
 
-void png_write_tEXt (png_structp png_ptr, png_charp key,
-png_charp text, png_size_t text_len);
+\fI\fB
 
-void png_write_tIME (png_structp png_ptr, png_timep mod_time);
+\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
 
-void png_write_tRNS (png_structp png_ptr, png_bytep trans,
-png_color_16p values, int number, int color_type);
+\fI\fB
 
-void png_write_zTXt (png_structp png_ptr, png_charp key,
-png_charp text, png_size_t text_len, int compression);
+\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
 
-voidpf png_zalloc (voidpf png_ptr, uInt items, uInt size);
+\fI\fB
 
-void png_zfree (voidpf png_ptr, voidpf ptr);
+\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

png.5

@@ -1,4 +1,4 @@
-.TH PNG 5 "December 29, 1998"
+.TH PNG 5 "November 29, 1999"
 .SH NAME
 png \- Portable Network Graphics (PNG) format
 .SH DESCRIPTION
@@ -20,7 +20,14 @@ platforms.
 .SH "SEE ALSO"
 .IR libpng(3), zlib(3), deflate(5), and zlib(5)
 .LP
-PNG specification:
+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
@@ -32,12 +39,19 @@ 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@dworkin.wustl.edu).
+Thomas Boutell and others (png-list@ccrc.wustl.edu).
 .LP
 
+
 .SH COPYRIGHT NOTICE
-The PNG specification is copyright (c) 1996 Massachussets Institute of
+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

@@ -1,10 +1,10 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * libpng version 1.0.2a - December 29, 1998
+ * libpng version 1.0.5d - November 29, 1999
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  * 
  */
 
@@ -16,32 +16,32 @@
  * string defined in png.h.
  */
 
-char png_libpng_ver[12] = "1.0.2a";
+#ifdef PNG_USE_GLOBAL_ARRAYS
+/* png_libpng_ver was changed to a function in version 1.0.5c */
+char png_libpng_ver[12] = "1.0.5d";
 
+/* png_sig was changed to a function in version 1.0.5c */
 /* 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[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'};
+ 
+/* Invoke global declarations for constant strings for known chunk types */
+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;
 
 /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
 
@@ -73,12 +73,14 @@ int FARDATA png_pass_mask[] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
 /* Mask to determine which pixels to overwrite while displaying */
 int FARDATA png_pass_dsp_mask[] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
 
+#endif
 
 /* 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)
 {
@@ -86,7 +88,7 @@ png_set_sig_bytes(png_structp png_ptr, int num_bytes)
    if (num_bytes > 8)
       png_error(png_ptr, "Too many bytes for PNG signature.");
 
-   png_ptr->sig_bytes = num_bytes < 0 ? 0 : num_bytes;
+   png_ptr->sig_bytes = (png_byte)(num_bytes < 0 ? 0 : num_bytes);
 }
 
 /* Checks whether the supplied bytes match the PNG signature.  We allow
@@ -100,6 +102,7 @@ png_set_sig_bytes(png_structp png_ptr, int num_bytes)
 int
 png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
 {
+   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
    if (num_to_check > 8)
       num_to_check = 8;
    else if (num_to_check < 1)
@@ -111,12 +114,12 @@ png_sig_cmp(png_bytep sig, png_size_t start, png_size_t num_to_check)
    if (start + num_to_check > 8)
       num_to_check = 8 - start;
 
-   return ((int)(png_memcmp(&sig[start], &png_sig[start], num_to_check)));
+   return ((int)(png_memcmp(&sig[start], &png_signature[start], num_to_check)));
 }
 
 /* (Obsolete) function to check signature bytes.  It does not allow one
- * to check a partial signature.  This function will be removed in the
- * future - use png_sig_cmp().
+ * 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)
@@ -265,9 +268,14 @@ png_info_destroy(png_structp png_ptr, png_infop info_ptr)
       int i;
       for (i = 0; i < info_ptr->num_text; i++)
       {
-         png_free(png_ptr, info_ptr->text[i].key);
+         if(info_ptr->text[i].key != NULL)
+         {
+           png_free(png_ptr, info_ptr->text[i].key);
+           info_ptr->text[i].key = NULL;
+         }
       }
       png_free(png_ptr, info_ptr->text);
+      info_ptr->text = NULL;
    }
 #endif
 #if defined(PNG_READ_pCAL_SUPPORTED)
@@ -279,8 +287,10 @@ png_info_destroy(png_structp png_ptr, png_infop info_ptr)
       for (i = 0; i < (int)info_ptr->pcal_nparams; i++)
       {
          png_free(png_ptr, info_ptr->pcal_params[i]);
+         info_ptr->pcal_params[i]=NULL;
       }
       png_free(png_ptr, info_ptr->pcal_params);
+      info_ptr->pcal_params = NULL;
    }
 #endif
 
@@ -347,12 +357,65 @@ png_convert_to_rfc1123(png_structp png_ptr, png_timep ptime)
 }
 #endif /* PNG_TIME_RFC1123_SUPPORTED */
 
+/* Signature string for a PNG file. */
+png_bytep
+png_sig_bytes(png_structp png_ptr)
+{
+   const png_byte png_sig_numbers[9] = {137, 80, 78, 71, 13, 10, 26, 10, 0};
+   if (png_ptr == NULL) /* silence compiler warning */
+     return ((png_bytep) strdup((png_const_charp)png_sig_numbers));
+   return ((png_bytep) strdup((png_const_charp)png_sig_numbers));
+}
+
 png_charp
 png_get_copyright(png_structp png_ptr)
 {
-   return("\n libpng version 1.0.2a - December 29, 1998\n\
+   if (png_ptr != NULL || png_ptr == NULL)  /* silence compiler warning */
+   return ("\n libpng version 1.0.5d - November 29, 1999\n\
    Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.\n\
    Copyright (c) 1996, 1997 Andreas Dilger\n\
-   Copyright (c) 1998, Glenn Randers-Pehrson\n");
+   Copyright (c) 1998, 1999 Glenn Randers-Pehrson\n");
+   return ("");
 }
 
+/* The following return the library version as a short string in the
+ * format 1.0.0 through 99.99.99zz.  To get the version of *.h files used
+ * with your application, print out PNG_LIBPNG_VER_STRING, which is defined
+ * in png.h.
+ */
+
+png_charp
+png_get_libpng_ver(png_structp png_ptr)
+{
+   /* Version of *.c files used when building libpng */
+   if(png_ptr != NULL) /* silence compiler warning about unused png_ptr */
+      return("1.0.5d");
+   return("1.0.5d");
+}
+
+png_charp
+png_get_header_ver(png_structp png_ptr)
+{
+   /* Version of *.h files used when building libpng */
+   if(png_ptr != NULL) /* silence compiler warning about unused png_ptr */
+      return(PNG_LIBPNG_VER_STRING);
+   return(PNG_LIBPNG_VER_STRING);
+}
+
+png_charp
+png_get_header_version(png_structp png_ptr)
+{
+   /* Returns longer string containing both version and date */
+   if(png_ptr != NULL) /* silence compiler warning about unused png_ptr */
+      return(PNG_HEADER_VERSION_STRING);
+   return(PNG_HEADER_VERSION_STRING);
+}
+
+/* Generate a compiler error if there is an old png.h in the search path. */
+void
+png_check_version
+   (version_1_0_5d png_h_is_not_version_1_0_5d)
+{
+   if(png_h_is_not_version_1_0_5d == NULL)
+     return;
+}

png.h

@@ -1,51 +1,132 @@
 
 /* png.h - header file for PNG reference library
  *
- * libpng version 1.0.2a - December 29, 1998
+ * libpng version 1.0.5d - November 29, 1999
  * Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.
  * Copyright (c) 1996, 1997 Andreas Dilger
- * Copyright (c) 1998, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  *
+ * Authors and maintainers:
+ *  libpng versions 0.71, May 1995, through 0.89c, May 1996: Guy Schalnat
+ *  libpng versions 0.90, December 1996, through 0.96, May 1997: Andreas Dilger
+ *  libpng versions 0.97, January 1998, through 1.0.5d - November 29, 1999: Glenn
+ *  See also "Contributing Authors", below.
+ *
+ * Y2K compliance in libpng:
+ * =========================
+ *    
+ *    November 29, 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 1.0.5d 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.c: 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 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
+ * 
  * Note about libpng version numbers:
- *
+ * 
  *    Due to various miscommunications, unforeseen code incompatibilities
  *    and occasional factors outside the authors' control, version numbering
  *    on the library has not always been consistent and straightforward.
  *    The following table summarizes matters since version 0.89c, which was
  *    the first widely used release:
  *
- *    source                    png.h    png.h   shared-lib
- *    version                   string     int   version
- *    -------                   ------   -----  ----------
- *    0.89c ("1.0 beta 3")      0.89        89  1.0.89
- *    0.90  ("1.0 beta 4")      0.90        90  0.90  [should have been 2.0.90]
- *    0.95  ("1.0 beta 5")      0.95        95  0.95  [should have been 2.0.95]
- *    0.96  ("1.0 beta 6")      0.96        96  0.96  [should have been 2.0.96]
- *    0.97b ("1.00.97 beta 7")  1.00.97     97  1.0.1 [should have been 2.0.97]
- *    0.97c                     0.97        97  2.0.97
- *    0.98                      0.98        98  2.0.98
- *    0.99                      0.99        98  2.0.99
- *    0.99a-m                   0.99        99  2.0.99
- *    1.00                      1.00       100  2.1.0 [int should be 10000]
- *    1.0.0                     1.0.0      100  2.1.0 [int should be 10000]
- *    1.0.1                     1.0.1    10001  2.1.0
- *    1.0.1a-e                  1.0.1a-e 10002  2.1.0.1a-e
- *    1.0.2                     1.0.2    10002  2.1.0.2
- *    1.0.2a                    1.0.2a   10003  2.1.0.2a
- *    1.0.3                     1.0.3    10003  2.1.0.3
+ *    source                   png.h    png.h   shared-lib
+ *    version                  string     int   version
+ *    -------                  ------   -----  ----------
+ *    0.89c ("1.0 beta 3")     0.89        89  1.0.89
+ *    0.90  ("1.0 beta 4")     0.90        90  0.90  [should have been 2.0.90]
+ *    0.95  ("1.0 beta 5")     0.95        95  0.95  [should have been 2.0.95]
+ *    0.96  ("1.0 beta 6")     0.96        96  0.96  [should have been 2.0.96]
+ *    0.97b ("1.00.97 beta 7") 1.00.97     97  1.0.1 [should have been 2.0.97]
+ *    0.97c                    0.97        97  2.0.97
+ *    0.98                     0.98        98  2.0.98
+ *    0.99                     0.99        98  2.0.99
+ *    0.99a-m                  0.99        99  2.0.99
+ *    1.00                     1.00       100  2.1.0 [100 should be 10000]
+ *    1.0.0                    1.0.0      100  2.1.0 [100 should be 10000]
+ *    1.0.1                    1.0.1    10001  2.1.0
+ *    1.0.1a-e                 1.0.1a-e 10002  2.1.0.1a-e
+ *    1.0.2                    1.0.2    10002  2.1.0.2
+ *    1.0.2a-b                 1.0.2a-b 10003  2.1.0.2a-b
+ *    1.0.3                    1.0.3    10003  2.1.0.3
+ *    1.0.3a-d                 1.0.3a-d 10004  2.1.0.3a-d
+ *    1.0.4                    1.0.4    10004  2.1.0.4
+ *    1.0.4a-f                 1.0.4a-f 10005  2.1.0.4a-f
+ *    1.0.5                    1.0.5    10005  2.1.0.5
+ *    1.0.5a-d                 1.0.5a-d 10006  2.1.0.5a-d
+ *    1.0.6                    1.0.6    10006  2.1.0.6
  *
  *    Henceforth the source version will match the shared-library minor
  *    and patch numbers; the shared-library major version number will be
  *    used for changes in backward compatibility, as it is intended.  The
  *    PNG_PNGLIB_VER macro, which is not used within libpng but is available
  *    for applications, is an unsigned integer of the form xyyzz corresponding
- *    to the source version x.y.z (leading zeros in y and z).
+ *    to the source version x.y.z (leading zeros in y and z).  Internal
+ *    png-group beta versions (x.y.z[a-z]) will be given the next higher
+ *    number.
  *
  * See libpng.txt or libpng.3 for more information.  The PNG specification
  * is available as RFC 2083 <ftp://ftp.uu.net/graphics/png/documents/>
  * and as a W3C Recommendation <http://www.w3.org/TR/REC.png.html>
+ */
+
+/*
+ * 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 1.0.5d, November 29, 1999)
+ *
+ * For the purposes of this copyright and license, "Contributing Authors"
+ * is defined as the following set of individuals:
  *
- * Contributing Authors:
  *    John Bowler
  *    Kevin Bracey
  *    Sam Bushell
@@ -61,14 +142,6 @@
  *    Willem van Schaik
  *    Tim Wegner
  *
- * The contributing authors would like to thank all those who helped
- * with testing, bug fixes, and patience.  This wouldn't have been
- * possible without all of you.
- *
- * Thanks to Frank J. T. Wojcik for helping with the documentation.
- *
- * COPYRIGHT NOTICE:
- *
  * 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
@@ -80,11 +153,17 @@
  * 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.
+ *
+ * 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
@@ -93,13 +172,32 @@
  * appreciated.
  */
 
+/*
+ * A "png_get_copyright" function is available, for convenient use in "about"
+ * boxes and the like:
+ * 
+ * printf("%s",png_get_copyright(NULL));
+ * 
+ * Also, the PNG logo (in PNG format, of course) is supplied in the
+ * file "pngnow.png".
+ */
+
+/*
+ * Libpng is OSI Certified Open Source Software.  OSI Certified is a
+ * certification mark of the Open Source Initiative.
+ */
+
+/*
+ * The contributing authors would like to thank all those who helped
+ * with testing, bug fixes, and patience.  This wouldn't have been
+ * possible without all of you.
+ *
+ * Thanks to Frank J. T. Wojcik for helping with the documentation.
+ */
+
 #ifndef _PNG_H
 #define _PNG_H
 
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
 /* This is not the place to learn how to use libpng.  The file libpng.txt
  * describes how to use libpng, and the file example.c summarizes it
  * with some code on which to build.  This file is useful for looking
@@ -112,6 +210,11 @@ extern "C" {
 /* include all user configurable info */
 #include "pngconf.h"
 
+/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
+#ifdef __cplusplus
+extern "C" {
+#endif /* __cplusplus */
+
 /* This file is arranged in several sections.  The first section contains
  * structure and type definitions.  The second section contains the external
  * library functions, while the third has the internal library functions,
@@ -119,33 +222,42 @@ extern "C" {
  */
 
 /* Version information for png.h - this should match the version in png.c */
-#define PNG_LIBPNG_VER_STRING "1.0.2a"
+#define PNG_LIBPNG_VER_STRING "1.0.5d"
 
 /* Careful here.  At one time, Guy wanted to use 082, but that would be octal.
  * We must not include leading zeros.
  * Versions 0.7 through 1.0.0 were in the range 0 to 100 here (only
  * version 1.0.0 was mis-numbered 100 instead of 10000).  From
  * version 1.0.1 it's    xxyyzz, where x=major, y=minor, z=bugfix */
-#define PNG_LIBPNG_VER    10003  /* 1.0.3 */
+#define PNG_LIBPNG_VER    10006  /* 1.0.6 */
+
+/* Note to maintainer: update this number in scripts/pngdef.pas as well */
 
 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
 /* Version information for C files, stored in png.c.  This had better match
  * the version above.
  */
-extern char png_libpng_ver[12];   /* need room for 99.99.99aa */
+#ifdef PNG_USE_GLOBAL_ARRAYS
+PNG_EXPORT_VAR (char) png_libpng_ver[12];   /* need room for 99.99.99aa */
+#else
+#define png_libpng_ver png_get_header_ver(NULL)
+#endif
 
+#ifdef PNG_USE_GLOBAL_ARRAYS
+/* This was removed in version 1.0.5c */
 /* Structures to facilitate easy interlacing.  See png.c for more details */
-extern int FARDATA png_pass_start[7];
-extern int FARDATA png_pass_inc[7];
-extern int FARDATA png_pass_ystart[7];
-extern int FARDATA png_pass_yinc[7];
-extern int FARDATA png_pass_mask[7];
-extern int FARDATA png_pass_dsp_mask[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_start[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_inc[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_ystart[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_yinc[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_mask[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_dsp_mask[7];
 /* These aren't currently used.  If you need them, see png.c for more details
-extern int FARDATA png_pass_width[7];
-extern int FARDATA png_pass_height[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_width[7];
+PNG_EXPORT_VAR (int FARDATA) png_pass_height[7];
 */
+#endif
 
 #endif /* PNG_NO_EXTERN */
 
@@ -407,6 +519,9 @@ typedef struct png_info_struct
 typedef png_info FAR * png_infop;
 typedef png_info FAR * FAR * png_infopp;
 
+/* Maximum positive integer used in PNG is (2^31)-1 */
+#define PNG_MAX_UINT ((png_uint_32)0x7fffffffL)
+
 /* These describe the color_type field in png_info. */
 /* color type masks */
 #define PNG_COLOR_MASK_PALETTE    1
@@ -420,11 +535,11 @@ typedef png_info FAR * FAR * png_infopp;
 #define PNG_COLOR_TYPE_RGB_ALPHA  (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_ALPHA)
 #define PNG_COLOR_TYPE_GRAY_ALPHA (PNG_COLOR_MASK_ALPHA)
 
-/* This is for compression type. PNG 1.0 only defines the single type. */
+/* This is for compression type. PNG 1.0-1.2 only define the single type. */
 #define PNG_COMPRESSION_TYPE_BASE 0 /* Deflate method 8, 32K window */
 #define PNG_COMPRESSION_TYPE_DEFAULT PNG_COMPRESSION_TYPE_BASE
 
-/* This is for filter type. PNG 1.0 only defines the single type. */
+/* This is for filter type. PNG 1.0-1.2 only define the single type. */
 #define PNG_FILTER_TYPE_BASE      0 /* Single row per-byte filtering */
 #define PNG_FILTER_TYPE_DEFAULT   PNG_FILTER_TYPE_BASE
 
@@ -451,10 +566,10 @@ typedef png_info FAR * FAR * png_infopp;
 #define PNG_RESOLUTION_LAST       2 /* Not a valid value */
 
 /* These are for the sRGB chunk.  These values should NOT be changed. */
-#define PNG_sRGB_INTENT_SATURATION 0
-#define PNG_sRGB_INTENT_PERCEPTUAL 1
-#define PNG_sRGB_INTENT_ABSOLUTE   2
-#define PNG_sRGB_INTENT_RELATIVE   3
+#define PNG_sRGB_INTENT_PERCEPTUAL 0
+#define PNG_sRGB_INTENT_RELATIVE   1
+#define PNG_sRGB_INTENT_SATURATION 2
+#define PNG_sRGB_INTENT_ABSOLUTE   3
 #define PNG_sRGB_INTENT_LAST       4 /* Not a valid value */
 
 
@@ -522,7 +637,7 @@ typedef void (*png_user_transform_ptr) PNGARG((png_structp,
 #endif /* PNG_READ|WRITE_USER_TRANSFORM_SUPPORTED */
 
 typedef png_voidp (*png_malloc_ptr) PNGARG((png_structp, png_size_t));
-typedef void (*png_free_ptr) PNGARG((png_structp, png_structp));
+typedef void (*png_free_ptr) PNGARG((png_structp, png_voidp));
 
 /* The structure that holds the information to read and write PNG files.
  * The only people who need to care about what is inside of this are the
@@ -540,12 +655,19 @@ struct png_struct_def
    png_voidp error_ptr;       /* user supplied struct for error functions */
    png_rw_ptr write_data_fn;  /* function for writing output data */
    png_rw_ptr read_data_fn;   /* function for reading input data */
-#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
-    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   png_voidp io_ptr;          /* ptr to application struct for I/O functions*/
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
    png_user_transform_ptr read_user_transform_fn; /* user read transform */
+#endif
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
    png_user_transform_ptr write_user_transform_fn; /* user write transform */
 #endif
-   png_voidp io_ptr;          /* ptr to application struct for I/O functions*/
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   png_voidp user_transform_ptr; /* user supplied struct for user transform */
+   png_byte user_transform_depth;    /* bit depth of user transformed pixels */
+   png_byte user_transform_channels; /* channels in user transformed pixels */
+#endif
 
    png_uint_32 mode;          /* tells us where we are in the PNG file */
    png_uint_32 flags;         /* flags indicating various things to libpng */
@@ -614,13 +736,13 @@ struct png_struct_def
 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
    int gamma_shift;      /* number of "insignificant" bits 16-bit gamma */
    float gamma;          /* file gamma value */
-   float screen_gamma;   /* screen gamma value (display_gamma/viewing_gamma */
+   float screen_gamma;   /* screen gamma value (display_exponent) */
 #endif /* PNG_READ_GAMMA_SUPPORTED */
 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
-   png_bytep gamma_table;     /* gamma table for 8 bit depth files */
+   png_bytep gamma_table;     /* gamma table for 8-bit depth files */
    png_bytep gamma_from_1;    /* converts from 1.0 to screen */
    png_bytep gamma_to_1;      /* converts from file to 1.0 */
-   png_uint_16pp gamma_16_table; /* gamma table for 16 bit depth files */
+   png_uint_16pp gamma_16_table; /* gamma table for 16-bit depth files */
    png_uint_16pp gamma_16_from_1; /* converts from 1.0 to screen */
    png_uint_16pp gamma_16_to_1; /* converts from file to 1.0 */
 #endif /* PNG_READ_GAMMA_SUPPORTED || PNG_WRITE_GAMMA_SUPPORTED */
@@ -698,8 +820,17 @@ struct png_struct_def
    png_byte rgb_to_gray_green_coeff;
    png_byte rgb_to_gray_blue_coeff;
 #endif
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+   png_byte empty_plte_permitted;
+#endif
 };
 
+/* This prevents a compiler error in png_get_copyright() in png.c if png.c
+and png.h are both at * version 1.0.5d
+ */
+typedef png_structp version_1_0_5d;
+
 typedef png_struct FAR * FAR * png_structpp;
 
 /* Here are the function definitions most commonly used.  This is not
@@ -771,6 +902,8 @@ extern PNG_EXPORT(png_infop,png_create_info_struct)
 extern void png_info_init PNGARG((png_infop info_ptr));
 
 /* Writes all the PNG information before the image. */
+extern PNG_EXPORT(void,png_write_info_before_PLTE) PNGARG((png_structp png_ptr,
+   png_infop info_ptr));
 extern PNG_EXPORT(void,png_write_info) PNGARG((png_structp png_ptr,
    png_infop info_ptr));
 
@@ -794,8 +927,11 @@ extern PNG_EXPORT(void,png_convert_from_time_t) PNGARG((png_timep ptime,
 #endif /* PNG_WRITE_tIME_SUPPORTED */
 
 #if defined(PNG_READ_EXPAND_SUPPORTED)
-/* Expand data to 24 bit RGB, or 8 bit grayscale, with alpha if available. */
+/* Expand data to 24-bit RGB, or 8-bit grayscale, with alpha if available. */
 extern PNG_EXPORT(void,png_set_expand) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_gray_1_2_4_to_8) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_palette_to_rgb) PNGARG((png_structp png_ptr));
+extern PNG_EXPORT(void,png_set_tRNS_to_alpha) PNGARG((png_structp png_ptr));
 #endif /* PNG_READ_EXPAND_SUPPORTED */
 
 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
@@ -804,14 +940,14 @@ extern PNG_EXPORT(void,png_set_bgr) PNGARG((png_structp png_ptr));
 #endif /* PNG_READ_BGR_SUPPORTED || PNG_WRITE_BGR_SUPPORTED */
 
 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
-/* Expand the grayscale to 24 bit RGB if necessary. */
+/* Expand the grayscale to 24-bit RGB if necessary. */
 extern PNG_EXPORT(void,png_set_gray_to_rgb) PNGARG((png_structp png_ptr));
 #endif /* PNG_READ_GRAY_TO_RGB_SUPPORTED */
 
 #if defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
 /* Reduce RGB to grayscale. */
 extern PNG_EXPORT(void,png_set_rgb_to_gray) PNGARG((png_structp png_ptr,
-   int error_action, float red, float green ));
+   int error_action, double red, double green ));
 extern PNG_EXPORT(png_byte,png_get_rgb_to_gray_status) PNGARG((png_structp
    png_ptr));
 #endif /* PNG_READ_RGB_TO_GRAY_SUPPORTED */
@@ -844,19 +980,19 @@ extern PNG_EXPORT(void,png_set_filler) PNGARG((png_structp png_ptr,
 #endif /* PNG_READ_FILLER_SUPPORTED || PNG_WRITE_FILLER_SUPPORTED */
 
 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-/* Swap bytes in 16 bit depth files. */
+/* Swap bytes in 16-bit depth files. */
 extern PNG_EXPORT(void,png_set_swap) PNGARG((png_structp png_ptr));
 #endif /* PNG_READ_SWAP_SUPPORTED || PNG_WRITE_SWAP_SUPPORTED */
 
 #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_WRITE_PACK_SUPPORTED)
-/* Use 1 byte per pixel in 1, 2, or 4 bit depth files. */
+/* Use 1 byte per pixel in 1, 2, or 4-bit depth files. */
 extern PNG_EXPORT(void,png_set_packing) PNGARG((png_structp png_ptr));
 #endif /* PNG_READ_PACK_SUPPORTED || PNG_WRITE_PACK_SUPPORTED */
 
 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || defined(PNG_WRITE_PACKSWAP_SUPPORTED)
 /* Swap packing order of pixels in bytes. */
 extern PNG_EXPORT(void,png_set_packswap) PNGARG((png_structp png_ptr));
-#endif /* PNG_READ_PACKSWAP_SUPPORTED || PNG_WRITE_PACKSWAP_SUPPOR */
+#endif /* PNG_READ_PACKSWAP_SUPPORTED || PNG_WRITE_PACKSWAP_SUPPORTED */
 
 #if defined(PNG_READ_SHIFT_SUPPORTED) || defined(PNG_WRITE_SHIFT_SUPPORTED)
 /* Converts files to legal bit depths. */
@@ -887,7 +1023,7 @@ extern PNG_EXPORT(void,png_set_background) PNGARG((png_structp png_ptr,
 #endif /* PNG_READ_BACKGROUND_SUPPORTED */
 
 #if defined(PNG_READ_16_TO_8_SUPPORTED)
-/* strip the second byte of information from a 16 bit depth file. */
+/* strip the second byte of information from a 16-bit depth file. */
 extern PNG_EXPORT(void,png_set_strip_16) PNGARG((png_structp png_ptr));
 #endif /* PNG_READ_16_TO_8_SUPPORTED */
 
@@ -899,11 +1035,18 @@ extern PNG_EXPORT(void,png_set_dither) PNGARG((png_structp png_ptr,
 #endif /* PNG_READ_DITHER_SUPPORTED */
 
 #if defined(PNG_READ_GAMMA_SUPPORTED)
-/* Handle gamma correction. Screen_gamma=(display_gamma/viewing_gamma) */
+/* Handle gamma correction. Screen_gamma=(display_exponent) */
 extern PNG_EXPORT(void,png_set_gamma) PNGARG((png_structp png_ptr,
    double screen_gamma, double default_file_gamma));
 #endif /* PNG_READ_GAMMA_SUPPORTED */
 
+#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
+    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
+/* Permit or disallow empty PLTE (0: not permitted, 1: permitted) */
+extern PNG_EXPORT(void,png_permit_empty_plte) PNGARG((png_structp png_ptr,
+   int empty_plte_permitted));
+#endif /* PNG_READ_EMPTY_PLTE_SUPPORTED */
+
 #if defined(PNG_WRITE_FLUSH_SUPPORTED)
 /* Set how many lines between output flushes - 0 for no flushing */
 extern PNG_EXPORT(void,png_set_flush) PNGARG((png_structp png_ptr, int nrows));
@@ -1164,6 +1307,16 @@ extern PNG_EXPORT(void,png_set_write_user_transform_fn) PNGARG((png_structp
    png_ptr, png_user_transform_ptr write_user_transform_fn));
 #endif
 
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) || \
+    defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+extern PNG_EXPORT(void,png_set_user_transform_info) PNGARG((png_structp
+   png_ptr, png_voidp user_transform_ptr, int user_transform_depth,
+   int user_transform_channels));
+/* Return the user pointer associated with the user transform functions */
+extern PNG_EXPORT(png_voidp,png_get_user_transform_ptr)
+   PNGARG((png_structp png_ptr));
+#endif
+
 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
 /* Sets the function callbacks for the push reader, and a pointer to a
  * user-defined structure available to the callback functions.
@@ -1489,15 +1642,14 @@ extern PNG_EXPORT(void,png_set_tRNS) PNGARG((png_structp png_ptr,
 #define png_debug2(l, m, p1, p2)
 #endif
 
+extern PNG_EXPORT(png_bytep,png_sig_bytes) PNGARG((png_structp png_ptr));
+
 extern PNG_EXPORT(png_charp,png_get_copyright) PNGARG((png_structp png_ptr));
-#ifdef PNG_NO_EXTERN
+extern PNG_EXPORT(png_charp,png_get_header_ver) PNGARG((png_structp png_ptr));
 extern PNG_EXPORT(png_charp,png_get_header_version) PNGARG((png_structp png_ptr));
-png_charp
-png_get_header_version(png_structp png_ptr)
-{
-   return("\n libpng version 1.0.2a - December 29, 1998 (header)\n");
-}
-#endif
+extern PNG_EXPORT(png_charp,png_get_libpng_ver) PNGARG((png_structp png_ptr));
+
+#define PNG_HEADER_VERSION_STRING " libpng version 1.0.5d - November 29, 1999 (header)\n"
 
 #ifdef PNG_READ_COMPOSITE_NODIV_SUPPORTED
 /* With these routines we avoid an integer divide, which will be slower on
@@ -1515,14 +1667,14 @@ png_get_header_version(png_structp png_ptr)
  /* fg and bg should be in `gamma 1.0' space; alpha is the opacity          */
 
 #  define png_composite(composite, fg, alpha, bg)                            \
-     { png_uint_16 temp = ((png_uint_16)(fg) * (png_uint_16)(alpha) +        \
-                        (png_uint_16)(bg)*(png_uint_16)(255 -                \
+     { png_uint_16 temp = (png_uint_16)((png_uint_16)(fg) * (png_uint_16)(alpha) \
+                        +        (png_uint_16)(bg)*(png_uint_16)(255 -       \
                         (png_uint_16)(alpha)) + (png_uint_16)128);           \
        (composite) = (png_byte)((temp + (temp >> 8)) >> 8); }
 
 #  define png_composite_16(composite, fg, alpha, bg)                         \
-     { png_uint_32 temp = ((png_uint_32)(fg) * (png_uint_32)(alpha) +        \
-                        (png_uint_32)(bg)*(png_uint_32)(65535L -             \
+     { png_uint_32 temp = (png_uint_32)((png_uint_32)(fg) * (png_uint_32)(alpha) \
+                        + (png_uint_32)(bg)*(png_uint_32)(65535L -           \
                         (png_uint_32)(alpha)) + (png_uint_32)32768L);        \
        (composite) = (png_uint_16)((temp + (temp >> 16)) >> 16); }
 
@@ -1551,15 +1703,19 @@ png_get_header_version(png_structp png_ptr)
 /* Various modes of operation.  Note that after an init, mode is set to
  * zero automatically when the structure is created.
  */
-#define PNG_BEFORE_IHDR       0x00
-#define PNG_HAVE_IHDR         0x01
-#define PNG_HAVE_PLTE         0x02
-#define PNG_HAVE_IDAT         0x04
-#define PNG_AFTER_IDAT        0x08
-#define PNG_HAVE_IEND         0x10
-#define PNG_HAVE_gAMA         0x20
-#define PNG_HAVE_cHRM         0x40
-#define PNG_HAVE_sRGB         0x80
+#define PNG_BEFORE_IHDR             0x00
+#define PNG_HAVE_IHDR               0x01
+#define PNG_HAVE_PLTE               0x02
+#define PNG_HAVE_IDAT               0x04
+#define PNG_AFTER_IDAT              0x08
+#define PNG_HAVE_IEND               0x10
+#define PNG_HAVE_gAMA               0x20
+#define PNG_HAVE_cHRM               0x40
+#define PNG_HAVE_sRGB               0x80
+#define PNG_HAVE_CHUNK_HEADER      0x100
+#define PNG_WROTE_tIME             0x200
+#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
+#define PNG_BACKGROUND_IS_GRAY     0x800
 
 /* push model modes */
 #define PNG_READ_SIG_MODE   0
@@ -1623,9 +1779,7 @@ png_get_header_version(png_structp png_ptr)
 #define PNG_FLAG_FREE_PALETTE             0x1000
 #define PNG_FLAG_FREE_TRANS               0x2000
 #define PNG_FLAG_FREE_HIST                0x4000
-#define PNG_FLAG_HAVE_CHUNK_HEADER        0x8000L
-#define PNG_FLAG_WROTE_tIME              0x10000L
-#define PNG_FLAG_BACKGROUND_IS_GRAY      0x20000L
+
 
 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
                                      PNG_FLAG_CRC_ANCILLARY_NOWARN)
@@ -1644,30 +1798,53 @@ png_get_header_version(png_structp png_ptr)
 /* variables declared in png.c - only it needs to define PNG_NO_EXTERN */
 #if !defined(PNG_NO_EXTERN) || defined(PNG_ALWAYS_EXTERN)
 /* place to hold the signature string for a PNG file. */
-extern png_byte FARDATA png_sig[8];
+#ifdef PNG_USE_GLOBAL_ARRAYS
+   PNG_EXPORT_VAR (png_byte FARDATA) png_sig[8];
+#else
+#define png_sig png_sig_bytes(NULL)
+#endif
 
 /* Constant strings for known chunk types.  If you need to add a chunk,
- * add a string holding the name here.  See png.c for more details.  We
- * can't selectively include these, since we still check for chunk in the
- * wrong locations with these labels.
+ * define the name here, and add an invocation of the macro in png.c and
+ * wherever it's needed.
  */
-extern png_byte FARDATA png_IHDR[5];
-extern png_byte FARDATA png_IDAT[5];
-extern png_byte FARDATA png_IEND[5];
-extern png_byte FARDATA png_PLTE[5];
-extern png_byte FARDATA png_bKGD[5];
-extern png_byte FARDATA png_cHRM[5];
-extern png_byte FARDATA png_gAMA[5];
-extern png_byte FARDATA png_hIST[5];
-extern png_byte FARDATA png_oFFs[5];
-extern png_byte FARDATA png_pCAL[5];
-extern png_byte FARDATA png_pHYs[5];
-extern png_byte FARDATA png_sBIT[5];
-extern png_byte FARDATA png_sRGB[5];
-extern png_byte FARDATA png_tEXt[5];
-extern png_byte FARDATA png_tIME[5];
-extern png_byte FARDATA png_tRNS[5];
-extern png_byte FARDATA png_zTXt[5];
+#define PNG_IHDR const png_byte png_IHDR[5] = { 73,  72,  68,  82, '\0'}
+#define PNG_IDAT const png_byte png_IDAT[5] = { 73,  68,  65,  84, '\0'}
+#define PNG_IEND const png_byte png_IEND[5] = { 73,  69,  78,  68, '\0'}
+#define PNG_PLTE const png_byte png_PLTE[5] = { 80,  76,  84,  69, '\0'}
+#define PNG_bKGD const png_byte png_bKGD[5] = { 98,  75,  71,  68, '\0'}
+#define PNG_cHRM const png_byte png_cHRM[5] = { 99,  72,  82,  77, '\0'}
+#define PNG_gAMA const png_byte png_gAMA[5] = {103,  65,  77,  65, '\0'}
+#define PNG_hIST const png_byte png_hIST[5] = {104,  73,  83,  84, '\0'}
+#define PNG_oFFs const png_byte png_oFFs[5] = {111,  70,  70, 115, '\0'}
+#define PNG_pCAL const png_byte png_pCAL[5] = {112,  67,  65,  76, '\0'}
+#define PNG_pHYs const png_byte png_pHYs[5] = {112,  72,  89, 115, '\0'}
+#define PNG_sBIT const png_byte png_sBIT[5] = {115,  66,  73,  84, '\0'}
+#define PNG_sRGB const png_byte png_sRGB[5] = {115,  82,  71,  66, '\0'}
+#define PNG_tEXt const png_byte png_tEXt[5] = {116,  69,  88, 116, '\0'}
+#define PNG_tIME const png_byte png_tIME[5] = {116,  73,  77,  69, '\0'}
+#define PNG_tRNS const png_byte png_tRNS[5] = {116,  82,  78,  83, '\0'}
+#define PNG_zTXt const png_byte png_zTXt[5] = {122,  84,  88, 116, '\0'}
+
+#ifdef PNG_USE_GLOBAL_ARRAYS
+PNG_EXPORT_VAR (const png_byte FARDATA) png_IHDR[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_IDAT[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_IEND[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_PLTE[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_bKGD[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_cHRM[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_gAMA[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_hIST[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_oFFs[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_pCAL[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_pHYs[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_sBIT[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_sRGB[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_tEXt[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_tIME[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_tRNS[5];
+PNG_EXPORT_VAR (const png_byte FARDATA) png_zTXt[5];
+#endif /* PNG_USE_GLOBAL_ARRAYS */
 
 #endif /* PNG_NO_EXTERN */
 
@@ -1766,7 +1943,7 @@ PNG_EXTERN void png_save_uint_32 PNGARG((png_bytep buf, png_uint_32 i));
 PNG_EXTERN void png_save_int_32 PNGARG((png_bytep buf, png_int_32 i));
 #endif
 
-/* Place a 16 bit number into a buffer in PNG byte order.
+/* Place a 16-bit number into a buffer in PNG byte order.
  * The parameter is declared unsigned int, not png_uint_16,
  * just to avoid potential problems on pre-ANSI C compilers.
  */
@@ -2160,16 +2337,11 @@ PNG_EXTERN void png_push_read_zTXt PNGARG((png_structp png_ptr,
 
 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
 
-#endif
- 
-
 #endif /* PNG_INTERNAL */
 
 #ifdef __cplusplus
 }
 #endif
 
-#ifdef PNG_NO_EXTERN
-
 /* do not put anything past this line */
 #endif /* _PNG_H */

pngasmrd.h

@@ -0,0 +1,32 @@
+/* pngasmrd.h - assembler version of utilities to read a PNG file
+ *
+ * libpng 1.0.5d - November 29, 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 1.0.5d).
+ * 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

pngconf.h

@@ -1,11 +1,11 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  */
 
 /* Any machine specific code is near the front of this file, so if you
@@ -17,7 +17,6 @@
 #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
@@ -54,25 +53,24 @@
  * 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 has been #defined.
+ * unless (PNG_DEBUG > 0) has been #defined.
  *
  * #define PNG_NO_CONSOLE_IO
  * #define PNG_NO_STDIO
  */
 
-#ifdef PNG_DEBUG
-#  if (PNG_DEBUG > 0)
-#    include <stdio.h>
-#  endif
-#else
 #  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
-#endif
 
 /* This macro protects us against machines that don't have function
  * prototypes (ie K&R style headers).  If your compiler does not handle
@@ -173,7 +171,7 @@ __dont__ include it again
 #endif
 
 /* Codewarrior on NT has linking problems without this. */
-#if defined(__MWERKS__) && defined(WIN32)
+#if (defined(__MWERKS__) && defined(WIN32)) || defined(__STDC__)
 #define PNG_ALWAYS_EXTERN
 #endif
 
@@ -339,6 +337,10 @@ __dont__ include it again
 #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
@@ -384,6 +386,10 @@ __dont__ include it again
 #define PNG_WRITE_FLUSH_SUPPORTED
 #endif
 
+#ifndef PNG_NO_WRITE_EMPTY_PLTE
+#define PNG_WRITE_EMPTY_PLTE_SUPPORTED  /* useful for MNG applications */
+#endif
+
 #ifndef PNG_NO_STDIO
 #define PNG_TIME_RFC1123_SUPPORTED
 #endif
@@ -408,6 +414,20 @@ __dont__ include it again
 #define PNG_EASY_ACCESS_SUPPORTED
 #endif
 
+#ifndef PNG_NO_ASSEMBLER_CODE
+#define PNG_ASSEMBLER_CODE_SUPPORTED
+#endif
+
+/* Do not use global arrays (helps with building DLL's)
+ * They are no longer used in libpng itself, since version 1.0.5c,
+ * but might be required for some pre-1.0.5c applications.
+ */
+#ifdef PNG_NO_GLOBAL_ARRAYS
+#define PNG_USE_LOCAL_ARRAYS
+#else
+#define PNG_USE_GLOBAL_ARRAYS
+#endif
+
 /* These are currently experimental features, define them if you want */
 
 /* very little testing */
@@ -647,25 +667,55 @@ typedef charf *         png_zcharp;
 typedef charf * FAR *   png_zcharpp;
 typedef z_stream FAR *  png_zstreamp;
 
-/* allow for compilation as dll under MS Windows */
-#ifdef __WIN32DLL__
-#define PNG_EXPORT(type,symbol) __declspec(dllexport) type 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
+#ifndef PNG_EXPORT
+   /* allow for compilation as dll under MS Windows */
+#  ifdef __WIN32DLL__
+#    define PNG_EXPORT(type,symbol) __declspec(dllexport) type symbol
+#  endif
 
-/* allow for compilation as shared lib under BeOS */
-#ifdef __BEOSDLL__
-#define PNG_EXPORT(type,symbol) __declspec(export) type symbol
+   /* 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
+#  define PNG_EXPORT(type,symbol) type symbol
 #endif
 
+#if defined(__MINGW32__) || defined(__CYGWIN32__)
+#  define PNG_ATTR_DLLIMP
+#endif
+
+#ifndef PNG_EXPORT_VAR
+#  ifdef PNG_DECL_DLLEXP
+#    define PNG_EXPORT_VAR(type) extern __declspec(dllexport) type
+#  endif
+#  ifdef PNG_ATTR_DLLEXP
+#    define PNG_EXPORT_VAR(type) extern type __attribute__((dllexport)) 
+#  endif
+#  ifdef PNG_DECL_DLLIMP
+#    define PNG_EXPORT_VAR(type) extern __declspec(dllimport) type
+#  endif
+#  ifdef PNG_ATTR_DLLIMP
+#    define PNG_EXPORT_VAR(type) extern type __attribute__((dllimport))
+#  endif
+#endif
+
+#ifndef PNG_EXPORT_VAR
+#    define PNG_EXPORT_VAR(type) extern type
+#endif
 
 /* User may want to use these so not in PNG_INTERNAL. Any library functions
  * that are passed far data must be model independent.

pngerror.c

@@ -1,11 +1,11 @@
 
 /* pngerror.c - stub functions for i/o and memory allocation
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * 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
@@ -75,7 +75,7 @@ png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp message
          buffer[iout++] = png_digit[c & 0xf];
          buffer[iout++] = ']';
       } else {
-         buffer[iout++] = c;
+         buffer[iout++] = (png_byte)c;
       }
    }
 
@@ -136,12 +136,11 @@ png_default_error(png_structp png_ptr, png_const_charp message)
 static void
 png_default_warning(png_structp png_ptr, png_const_charp message)
 {
-   if (png_ptr == NULL)
-      return;
-
 #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

pngget.c

@@ -1,11 +1,11 @@
 
 /* pngget.c - retrieval of values from info struct
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  */
 
 #define PNG_INTERNAL
@@ -454,7 +454,7 @@ png_get_IHDR(png_structp png_ptr, png_infop info_ptr,
          channels++;
       pixel_depth = *bit_depth * channels;
       rowbytes_per_pixel = (pixel_depth + 7) >> 3;
-      if ((*width > (png_uint_32)2147483647L/rowbytes_per_pixel))
+      if ((*width > PNG_MAX_UINT/rowbytes_per_pixel))
       {
          png_warning(png_ptr,
             "Width too large for libpng to process image data.");

pngmem.c

@@ -1,11 +1,11 @@
 
 /* pngmem.c - stub functions for memory allocation
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * 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
@@ -82,12 +82,10 @@ png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
          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;
    }
 }
 
@@ -157,8 +155,9 @@ png_malloc_default(png_structp png_ptr, png_uint_32 size)
                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));
@@ -192,12 +191,12 @@ png_malloc_default(png_structp png_ptr, png_uint_32 size)
             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 += (png_uint_32)65536L;
+               hptr = hptr + (png_uint_32)65536L;  /* "+=" fails on TC++3.0 */
             }
 
             png_ptr->offset_table_number = num_blocks;
@@ -235,7 +234,6 @@ png_free(png_structp png_ptr, png_voidp ptr)
    if (png_ptr->free_fn != NULL)
    {
       (*(png_ptr->free_fn))(png_ptr, ptr);
-      ptr = NULL;
       return;
    }
    else png_free_default(png_ptr, ptr);
@@ -271,7 +269,6 @@ png_free_default(png_structp png_ptr, png_voidp ptr)
    if (ptr != NULL)
    {
       farfree(ptr);
-      ptr = NULL;
    }
 }
 
@@ -351,20 +348,16 @@ png_destroy_struct_2(png_voidp struct_ptr, png_free_ptr free_fn)
          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
    }
@@ -433,7 +426,6 @@ png_free(png_structp png_ptr, png_voidp ptr)
    if (png_ptr->free_fn != NULL)
    {
       (*(png_ptr->free_fn))(png_ptr, ptr);
-      ptr = NULL;
       return;
    }
    else png_free_default(png_ptr, ptr);
@@ -441,18 +433,18 @@ png_free(png_structp png_ptr, png_voidp ptr)
 void
 png_free_default(png_structp png_ptr, png_voidp ptr)
 {
+   if (png_ptr == NULL || ptr == NULL)
+      return;
+
 #endif /* PNG_USER_MEM_SUPPORTED */
 
 #if defined(__TURBOC__) && !defined(__FLAT__)
    farfree(ptr);
-   ptr = NULL;
 #else
 # if defined(_MSC_VER) && defined(MAXSEG_64K)
    hfree(ptr);
-   ptr = NULL;
 # else
    free(ptr);
-   ptr = NULL;
 # endif
 #endif
 }

pngpread.c

@@ -1,11 +1,11 @@
 
 /* pngpread.c - read a png file in push mode
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  */
 
 #define PNG_INTERNAL
@@ -94,7 +94,7 @@ png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
 
    png_push_fill_buffer(png_ptr, &(info_ptr->signature[num_checked]),
       num_to_check);
-   png_ptr->sig_bytes += num_to_check;
+   png_ptr->sig_bytes = (png_byte)(png_ptr->sig_bytes+num_to_check);
 
    if (png_sig_cmp(info_ptr->signature, num_checked, num_to_check))
    {
@@ -116,13 +116,58 @@ png_push_read_sig(png_structp png_ptr, png_infop info_ptr)
 void
 png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IHDR;
+      PNG_IDAT;
+      PNG_IEND;
+      PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      PNG_hIST;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      PNG_sBIT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      PNG_zTXt;
+#endif
+#endif /* PNG_USE_LOCAL_ARRAYS */
    /* First we make sure we have enough data for the 4 byte chunk name
     * and the 4 byte chunk length before proceeding with decoding the
     * chunk data.  To fully decode each of these chunks, we also make
     * sure we have enough data in the buffer for the 4 byte CRC at the
     * end of every chunk (except IDAT, which is handled separately).
     */
-   if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER))
+   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
    {
       png_byte chunk_length[4];
 
@@ -136,7 +181,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
       png_ptr->push_length = png_get_uint_32(chunk_length);
       png_reset_crc(png_ptr);
       png_crc_read(png_ptr, png_ptr->chunk_name, 4);
-      png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
+      png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
    }
 
    if (!png_memcmp(png_ptr->chunk_name, png_IHDR, 4))
@@ -159,7 +204,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
 
       png_handle_PLTE(png_ptr, info_ptr, png_ptr->push_length);
    }
-   else if (!png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+   else if (!png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
    {
       /* If we reach an IDAT chunk, this means we have read all of the
        * header chunks, and we can start reading the image (or if this
@@ -343,7 +388,7 @@ png_push_read_chunk(png_structp png_ptr, png_infop info_ptr)
       png_push_handle_unknown(png_ptr, info_ptr, png_ptr->push_length);
    }
 
-   png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER;
+   png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
 }
 
 void
@@ -496,7 +541,10 @@ png_push_restore_buffer(png_structp png_ptr, png_bytep buffer,
 void
 png_push_read_IDAT(png_structp png_ptr)
 {
-   if (!(png_ptr->flags & PNG_FLAG_HAVE_CHUNK_HEADER))
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IDAT;
+#endif
+   if (!(png_ptr->mode & PNG_HAVE_CHUNK_HEADER))
    {
       png_byte chunk_length[4];
 
@@ -511,9 +559,9 @@ png_push_read_IDAT(png_structp png_ptr)
 
       png_reset_crc(png_ptr);
       png_crc_read(png_ptr, png_ptr->chunk_name, 4);
-      png_ptr->flags |= PNG_FLAG_HAVE_CHUNK_HEADER;
+      png_ptr->mode |= PNG_HAVE_CHUNK_HEADER;
 
-      if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+      if (png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
       {
          png_ptr->process_mode = PNG_READ_CHUNK_MODE;
          if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
@@ -576,7 +624,7 @@ png_push_read_IDAT(png_structp png_ptr)
       }
 
       png_crc_finish(png_ptr, 0);
-      png_ptr->flags &= ~PNG_FLAG_HAVE_CHUNK_HEADER;
+      png_ptr->mode &= ~PNG_HAVE_CHUNK_HEADER;
    }
 }
 
@@ -767,6 +815,32 @@ png_push_process_row(png_structp png_ptr)
 void
 png_read_push_finish_row(png_structp png_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* start of interlace block */
+   const int png_pass_start[] = {0, 4, 0, 2, 0, 1, 0};
+   
+   /* offset to next interlace block */
+   const int png_pass_inc[] = {8, 8, 4, 4, 2, 2, 1};
+   
+   /* start of interlace block in the y direction */
+   const int png_pass_ystart[] = {0, 0, 4, 0, 2, 0, 1};
+   
+   /* offset to next interlace block in the y direction */
+   const int 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
+   const int 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
+   const int png_pass_height[] = {8, 8, 4, 4, 2, 2, 1};
+   */
+#endif
+   
    png_ptr->row_number++;
    if (png_ptr->row_number < png_ptr->num_rows)
       return;
@@ -1115,6 +1189,9 @@ void
 png_progressive_combine_row (png_structp png_ptr,
    png_bytep old_row, png_bytep new_row)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   const int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+#endif
    if (new_row != NULL)    /* new_row must == png_ptr->row_buf here. */
       png_combine_row(png_ptr, old_row, png_pass_dsp_mask[png_ptr->pass]);
 }

pngread.c

@@ -1,11 +1,11 @@
 
 /* pngread.c - read a PNG file
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  *
  * This file contains routines that an application calls directly to
  * read a PNG file or stream.
@@ -179,6 +179,51 @@ png_read_info(png_structp png_ptr, png_infop info_ptr)
 
    for(;;)
    {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IHDR;
+      PNG_IDAT;
+      PNG_IEND;
+      PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      PNG_hIST;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      PNG_sBIT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      PNG_zTXt;
+#endif
+#endif /* PNG_GLOBAL_ARRAYS */
       png_byte chunk_length[4];
       png_uint_32 length;
 
@@ -188,7 +233,8 @@ png_read_info(png_structp png_ptr, png_infop info_ptr)
       png_reset_crc(png_ptr);
       png_crc_read(png_ptr, png_ptr->chunk_name, 4);
 
-      png_debug1(0, "Reading %s chunk.\n", png_ptr->chunk_name);
+      png_debug2(0, "Reading %s chunk, length=%d.\n", png_ptr->chunk_name,
+         length);
 
       /* This should be a binary subdivision search or a hash for
        * matching the chunk name rather than a linear search.
@@ -296,6 +342,11 @@ png_start_read_image(png_structp png_ptr)
 void
 png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IDAT;
+   const int png_pass_dsp_mask[7] = {0xff, 0x0f, 0xff, 0x33, 0xff, 0x55, 0xff};
+   const int png_pass_mask[7] = {0x80, 0x08, 0x88, 0x22, 0xaa, 0x55, 0xff};
+#endif
    int ret;
    png_debug2(1, "in png_read_row (row %d, pass %d)\n",
       png_ptr->row_number, png_ptr->pass);
@@ -464,10 +515,8 @@ png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
    png_ptr->row_info.channels = png_ptr->channels;
    png_ptr->row_info.bit_depth = png_ptr->bit_depth;
    png_ptr->row_info.pixel_depth = png_ptr->pixel_depth;
-   {
-      png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
-         (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
-   }
+   png_ptr->row_info.rowbytes = ((png_ptr->row_info.width *
+      (png_uint_32)png_ptr->row_info.pixel_depth + 7) >> 3);
 
    png_read_filter_row(png_ptr, &(png_ptr->row_info),
       png_ptr->row_buf + 1, png_ptr->prev_row + 1,
@@ -530,7 +579,7 @@ png_read_row(png_structp png_ptr, png_bytep row, png_bytep dsp_row)
  * not called png_set_interlace_handling(), the display_row buffer will
  * be ignored, so pass NULL to it.
  *
- * [*] png_handle_alpha() does not exist yet, as of libpng version 1.0.2a.
+ * [*] png_handle_alpha() does not exist yet, as of libpng version 1.0.5d.
  */
 
 void
@@ -579,7 +628,7 @@ png_read_rows(png_structp png_ptr, png_bytepp row,
  * only call this function once.  If you desire to have an image for
  * each pass of a interlaced image, use png_read_rows() instead.
  *
- * [*] png_handle_alpha() does not exist yet, as of libpng version 1.0.2a.
+ * [*] png_handle_alpha() does not exist yet, as of libpng version 1.0.5d.
  */
 void
 png_read_image(png_structp png_ptr, png_bytepp image)
@@ -590,7 +639,16 @@ png_read_image(png_structp png_ptr, png_bytepp image)
 
    png_debug(1, "in png_read_image\n");
    /* save jump buffer and error functions */
+
+#ifdef PNG_READ_INTERLACING_SUPPORTED
    pass = png_set_interlace_handling(png_ptr);
+#else
+   if (png_ptr->interlaced)
+      png_error(png_ptr,
+        "Cannot read interlaced image -- interlace handler disabled.");
+   pass = 1;
+#endif
+
 
    image_height=png_ptr->height;
    png_ptr->num_rows = image_height; /* Make sure this is set correctly */
@@ -622,6 +680,52 @@ png_read_end(png_structp png_ptr, png_infop info_ptr)
 
    do
    {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IHDR;
+      PNG_IDAT;
+      PNG_IEND;
+      PNG_PLTE;
+#if defined(PNG_READ_bKGD_SUPPORTED)
+      PNG_bKGD;
+#endif
+#if defined(PNG_READ_cHRM_SUPPORTED)
+      PNG_cHRM;
+#endif
+#if defined(PNG_READ_gAMA_SUPPORTED)
+      PNG_gAMA;
+#endif
+#if defined(PNG_READ_hIST_SUPPORTED)
+      PNG_hIST;
+#endif
+#if defined(PNG_READ_oFFs_SUPPORTED)
+      PNG_oFFs;
+#endif
+#if defined(PNG_READ_pCAL_SUPPORTED)
+      PNG_pCAL;
+#endif
+#if defined(PNG_READ_pHYs_SUPPORTED)
+      PNG_pHYs;
+#endif
+#if defined(PNG_READ_sBIT_SUPPORTED)
+      PNG_sBIT;
+#endif
+#if defined(PNG_READ_sRGB_SUPPORTED)
+      PNG_sRGB;
+#endif
+#if defined(PNG_READ_tEXt_SUPPORTED)
+      PNG_tEXt;
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED)
+      PNG_tIME;
+#endif
+#if defined(PNG_READ_tRNS_SUPPORTED)
+      PNG_tRNS;
+#endif
+#if defined(PNG_READ_zTXt_SUPPORTED)
+      PNG_zTXt;
+#endif
+#endif /* PNG_GLOBAL_ARRAYS */
+
       png_read_data(png_ptr, chunk_length, 4);
       length = png_get_uint_32(chunk_length);
 
@@ -805,8 +909,11 @@ png_read_destroy(png_structp png_ptr, png_infop info_ptr, png_infop end_info_ptr
 #endif
    if (png_ptr->flags & PNG_FLAG_FREE_PALETTE)
       png_zfree(png_ptr, png_ptr->palette);
+#if defined(PNG_READ_tRNS_SUPPORTED) || defined(PNG_WRITE_tRNS_SUPPORTED) || \
+    defined(PNG_READ_EXPAND_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED)
    if (png_ptr->flags & PNG_FLAG_FREE_TRANS)
       png_free(png_ptr, png_ptr->trans);
+#endif
 #if defined(PNG_READ_hIST_SUPPORTED)
    if (png_ptr->flags & PNG_FLAG_FREE_HIST)
       png_free(png_ptr, png_ptr->hist);

pngrio.c

@@ -1,11 +1,11 @@
 
 /* pngrio.c - functions for data input
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * 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

pngrtran.c

@@ -1,11 +1,11 @@
 
 /* pngrtran.c - transforms the data in a row for PNG readers
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  *
  * This file contains functions optionally called by an application
  * in order to tell libpng how to handle data when reading a PNG.
@@ -92,13 +92,13 @@ png_set_background(png_structp png_ptr,
    /* Note:  if need_expand is set and color_type is either RGB or RGB_ALPHA
     * (in which case need_expand is superfluous anyway), the background color
     * might actually be gray yet not be flagged as such. This is not a problem
-    * for the current code, which uses PNG_FLAG_BACKGROUND_IS_GRAY only to
+    * for the current code, which uses PNG_BACKGROUND_IS_GRAY only to
     * decide when to do the png_do_gray_to_rgb() transformation.
     */
    if ((need_expand && !(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) ||
        (!need_expand && background_color->red == background_color->green &&
         background_color->red == background_color->blue))
-      png_ptr->flags |= PNG_FLAG_BACKGROUND_IS_GRAY;
+      png_ptr->mode |= PNG_BACKGROUND_IS_GRAY;
 }
 #endif
 
@@ -522,8 +522,8 @@ png_set_gamma(png_structp png_ptr, double scrn_gamma, double file_gamma)
 #endif
 
 #if defined(PNG_READ_EXPAND_SUPPORTED)
-/* Expand paletted images to rgb, expand grayscale images of
- * less than 8 bit depth to 8 bit depth, and expand tRNS chunks
+/* Expand paletted images to RGB, expand grayscale images of
+ * less than 8-bit depth to 8-bit depth, and expand tRNS chunks
  * to alpha channels.
  */
 void
@@ -532,7 +532,45 @@ png_set_expand(png_structp png_ptr)
    png_debug(1, "in png_set_expand\n");
    png_ptr->transformations |= PNG_EXPAND;
 }
-#endif
+
+/* GRR 19990627:  the following three functions currently are identical
+ *  to png_set_expand().  However, it is entirely reasonable that someone
+ *  might wish to expand an indexed image to RGB but *not* expand a single,
+ *  fully transparent palette entry to a full alpha channel--perhaps instead
+ *  convert tRNS to the grayscale/RGB format (16-bit RGB value), or replace
+ *  the transparent color with a particular RGB value, or drop tRNS entirely.
+ *  IOW, a future version of the library may make the transformations flag
+ *  a bit more fine-grained, with separate bits for each of these three
+ *  functions.
+ *
+ *  More to the point, these functions make it obvious what libpng will be
+ *  doing, whereas "expand" can (and does) mean any number of things.
+ */
+
+/* Expand paletted images to RGB. */
+void
+png_set_palette_to_rgb(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+
+/* Expand grayscale images of less than 8-bit depth to 8 bits. */
+void
+png_set_gray_1_2_4_to_8(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+
+/* Expand tRNS chunks to alpha channels. */
+void
+png_set_tRNS_to_alpha(png_structp png_ptr)
+{
+   png_debug(1, "in png_set_expand\n");
+   png_ptr->transformations |= PNG_EXPAND;
+}
+#endif /* defined(PNG_READ_EXPAND_SUPPORTED) */
 
 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
 void
@@ -548,8 +586,8 @@ png_set_gray_to_rgb(png_structp png_ptr)
  * for example, to convert a 24 bpp RGB image into an 8 bpp grayscale image.
  */
 void
-png_set_rgb_to_gray(png_structp png_ptr, int error_action, float red,
-  float green)
+png_set_rgb_to_gray(png_structp png_ptr, int error_action, double red,
+  double green)
 {
    png_debug(1, "in png_set_rgb_to_gray\n");
    switch(error_action)
@@ -570,8 +608,8 @@ png_set_rgb_to_gray(png_structp png_ptr, int error_action, float red,
    }
 #endif
    {
-      png_byte red_byte = (png_byte)(red*255.0 + 0.5);
-      png_byte green_byte = (png_byte)(green*255.0 + 0.5);
+      png_byte red_byte = (png_byte)((float)red*255.0 + 0.5);
+      png_byte green_byte = (png_byte)((float)green*255.0 + 0.5);
       if(red < 0.0 || green < 0.0)
       {
          red_byte = 54;
@@ -585,7 +623,7 @@ png_set_rgb_to_gray(png_structp png_ptr, int error_action, float red,
       }
       png_ptr->rgb_to_gray_red_coeff   = red_byte;
       png_ptr->rgb_to_gray_green_coeff = green_byte;
-      png_ptr->rgb_to_gray_blue_coeff  = 255 - red_byte - green_byte;
+      png_ptr->rgb_to_gray_blue_coeff  = (png_byte)(255-red_byte-green_byte);
    }
 }
 #endif
@@ -668,7 +706,7 @@ png_init_read_transformations(png_structp png_ptr)
               int i,istop;
               istop=(int)png_ptr->num_trans;
               for (i=0; i<istop; i++)
-                 png_ptr->trans[i] = 255 - png_ptr->trans[i];
+                 png_ptr->trans[i] = (png_byte)(255 - png_ptr->trans[i]);
            }
         }
 #endif
@@ -1015,12 +1053,23 @@ png_read_transform_info(png_structp png_ptr, png_infop info_ptr)
    if (png_ptr->transformations & PNG_FILLER &&
        (info_ptr->color_type == PNG_COLOR_TYPE_RGB ||
         info_ptr->color_type == PNG_COLOR_TYPE_GRAY))
-      ++info_ptr->channels;
+      info_ptr->channels++;
+#endif
+
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   if(png_ptr->transformations & PNG_USER_TRANSFORM)
+     {
+       if(info_ptr->bit_depth < png_ptr->user_transform_depth)
+         info_ptr->bit_depth = png_ptr->user_transform_depth;
+       if(info_ptr->channels < png_ptr->user_transform_channels)
+         info_ptr->channels = png_ptr->user_transform_channels;
+     }
 #endif
 
    info_ptr->pixel_depth = (png_byte)(info_ptr->channels *
       info_ptr->bit_depth);
    info_ptr->rowbytes = ((info_ptr->width * info_ptr->pixel_depth + 7) >> 3);
+
 }
 
 /* Transform the row.  The order of transformations is significant,
@@ -1122,7 +1171,7 @@ From Andreas Dilger e-mail to png-implement, 26 March 1998:
    /* if gray -> RGB, do so now only if background is non-gray; else do later
     * for performance reasons */
    if (png_ptr->transformations & PNG_GRAY_TO_RGB &&
-       !(png_ptr->flags & PNG_FLAG_BACKGROUND_IS_GRAY))
+       !(png_ptr->mode & PNG_BACKGROUND_IS_GRAY))
       png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
 
@@ -1196,7 +1245,7 @@ From Andreas Dilger e-mail to png-implement, 26 March 1998:
 #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)
    /* if gray -> RGB, do so now only if we did not do so above */
    if (png_ptr->transformations & PNG_GRAY_TO_RGB &&
-       png_ptr->flags & PNG_FLAG_BACKGROUND_IS_GRAY)
+       png_ptr->mode & PNG_BACKGROUND_IS_GRAY)
       png_do_gray_to_rgb(&(png_ptr->row_info), png_ptr->row_buf + 1);
 #endif
 
@@ -1223,6 +1272,7 @@ From Andreas Dilger e-mail to png-implement, 26 March 1998:
 
 #if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
    if (png_ptr->transformations & PNG_USER_TRANSFORM)
+    {
       if(png_ptr->read_user_transform_fn != NULL)
         (*(png_ptr->read_user_transform_fn)) /* user read transform function */
           (png_ptr,                    /* png_ptr */
@@ -1234,6 +1284,15 @@ From Andreas Dilger e-mail to png-implement, 26 March 1998:
              /*  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 */
+      if(png_ptr->user_transform_depth)
+         png_ptr->row_info.bit_depth = png_ptr->user_transform_depth;
+      if(png_ptr->user_transform_channels)
+         png_ptr->row_info.channels = png_ptr->user_transform_channels;
+      png_ptr->row_info.pixel_depth = (png_byte)(png_ptr->row_info.bit_depth *
+         png_ptr->row_info.channels);
+      png_ptr->row_info.rowbytes = (png_ptr->row_info.width * 
+         png_ptr->row_info.pixel_depth+7)>>3;
+   }
 #endif
 
 }
@@ -1397,8 +1456,8 @@ png_do_unshift(png_row_infop row_info, png_bytep row, png_color_8p sig_bits)
             png_bytep bp = row;
             png_uint_32 i;
             png_uint_32 istop = row_info->rowbytes;
-            png_byte mask = (png_byte)(((int)0xf0 >> shift[0]) & (int)0xf0) |
-               (png_byte)((int)0xf >> shift[0]);
+            png_byte mask = (png_byte)((((int)0xf0 >> shift[0]) & (int)0xf0) |
+               (png_byte)((int)0xf >> shift[0]));
 
             for (i = 0; i < istop; i++)
             {
@@ -1607,7 +1666,7 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
 
             for (i = 0; i < row_width; i++)
             {
-               *(--dp) = 255 - *(--sp);
+               *(--dp) = (png_byte)(255 - *(--sp));
                *(--dp) = *(--sp);
                *(--dp) = *(--sp);
                *(--dp) = *(--sp);
@@ -1622,8 +1681,8 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
 
             for (i = 0; i < row_width; i++)
             {
-               *(--dp) = 255 - *(--sp);
-               *(--dp) = 255 - *(--sp);
+               *(--dp) = (png_byte)(255 - *(--sp));
+               *(--dp) = (png_byte)(255 - *(--sp));
                *(--dp) = *(--sp);
                *(--dp) = *(--sp);
                *(--dp) = *(--sp);
@@ -1644,7 +1703,7 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
 
             for (i = 0; i < row_width; i++)
             {
-               *(--dp) = 255 - *(--sp);
+               *(--dp) = (png_byte)(255 - *(--sp));
                *(--dp) = *(--sp);
             }
          }
@@ -1657,8 +1716,8 @@ png_do_read_invert_alpha(png_row_infop row_info, png_bytep row)
 
             for (i = 0; i < row_width; i++)
             {
-               *(--dp) = 255 - *(--sp);
-               *(--dp) = 255 - *(--sp);
+               *(--dp) = (png_byte)(255 - *(--sp));
+               *(--dp) = (png_byte)(255 - *(--sp));
                *(--dp) = *(--sp);
                *(--dp) = *(--sp);
             }
@@ -1737,7 +1796,7 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
             *(--dp) = lo_filler;
             row_info->channels = 2;
             row_info->pixel_depth = 32;
-            row_info->rowbytes = row_width * 2;
+            row_info->rowbytes = row_width * 4;
          }
          /* This changes the data from GG to XXGG */
          else
@@ -1752,8 +1811,8 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
                *(--dp) = lo_filler;
             }
             row_info->channels = 2;
-            row_info->pixel_depth = 16;
-            row_info->rowbytes = row_width * 2;
+            row_info->pixel_depth = 32;
+            row_info->rowbytes = row_width * 4;
          }
       }
    } /* COLOR_TYPE == GRAY */
@@ -1817,7 +1876,7 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
             *(--dp) = lo_filler;
             row_info->channels = 4;
             row_info->pixel_depth = 64;
-            row_info->rowbytes = row_width * 4;
+            row_info->rowbytes = row_width * 8;
          }
          /* This changes the data from RRGGBB to XXRRGGBB */
          else
@@ -1837,7 +1896,7 @@ png_do_read_filler(png_row_infop row_info, png_bytep row,
             }
             row_info->channels = 4;
             row_info->pixel_depth = 64;
-            row_info->rowbytes = row_width * 4;
+            row_info->rowbytes = row_width * 8;
          }
       }
    } /* COLOR_TYPE == RGB */
@@ -1869,8 +1928,7 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
             {
                *(dp--) = *sp;
                *(dp--) = *sp;
-               *(dp--) = *sp;
-               sp--;
+               *(dp--) = *(sp--);
             }
          }
          else
@@ -1883,10 +1941,8 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
                *(dp--) = *(sp - 1);
                *(dp--) = *sp;
                *(dp--) = *(sp - 1);
-               *(dp--) = *sp;
-               *(dp--) = *(sp - 1);
-               sp--;
-               sp--;
+               *(dp--) = *(sp--);
+               *(dp--) = *(sp--);
             }
          }
       }
@@ -1901,8 +1957,7 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
                *(dp--) = *(sp--);
                *(dp--) = *sp;
                *(dp--) = *sp;
-               *(dp--) = *sp;
-               sp--;
+               *(dp--) = *(sp--);
             }
          }
          else
@@ -1917,10 +1972,8 @@ png_do_gray_to_rgb(png_row_infop row_info, png_bytep row)
                *(dp--) = *(sp - 1);
                *(dp--) = *sp;
                *(dp--) = *(sp - 1);
-               *(dp--) = *sp;
-               *(dp--) = *(sp - 1);
-               sp--;
-               sp--;
+               *(dp--) = *(sp--);
+               *(dp--) = *(sp--);
             }
          }
       }
@@ -2012,7 +2065,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                   if(red != green || red != blue)
                   {
                      rgb_error |= 1;
-                     *(dp++) = (rc*red+gc*green+bc*blue)>>8;
+                     *(dp++) = (png_byte)((rc*red+gc*green+bc*blue)>>8);
                   }
                   else
                      *(dp++) = *(sp-1);
@@ -2032,9 +2085,9 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                {
                   png_uint_16 red, green, blue, w;
 
-                  red   = ((*(sp))<<8) | *(sp+1); sp+=2;
-                  green = ((*(sp))<<8) | *(sp+1); sp+=2;
-                  blue  = ((*(sp))<<8) | *(sp+1); sp+=2;
+                  red   = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
 
                   if(red == green && red == blue)
                      w = red;
@@ -2046,15 +2099,15 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                                   png_ptr->gamma_shift][green>>8];
                      png_uint_16 blue_1  = png_ptr->gamma_16_to_1[(blue&0xff) >> 
                                   png_ptr->gamma_shift][blue>>8];
-                     png_uint_16 gray16  =  (rc * red_1 + gc * green_1
-                                  + bc * blue_1)>>8;
+                     png_uint_16 gray16  = (png_uint_16)((rc*red_1 + gc*green_1
+                                  + bc*blue_1)>>8);
                      w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
                          png_ptr->gamma_shift][gray16 >> 8];
                      rgb_error |= 1;
                   }
                   
-                  *(dp++) = (w>>8) & 0xff;
-                  *(dp++) = w & 0xff;
+                  *(dp++) = (png_byte)((w>>8) & 0xff);
+                  *(dp++) = (png_byte)(w & 0xff);
                }
             }
             else
@@ -2066,15 +2119,15 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                {
                   png_uint_16 red, green, blue, gray16;
 
-                  red   = ((*(sp))<<8) | *(sp+1); sp+=2;
-                  green = ((*(sp))<<8) | *(sp+1); sp+=2;
-                  blue  = ((*(sp))<<8) | *(sp+1); sp+=2;
+                  red   = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
 
                   if(red != green || red != blue)
                      rgb_error |= 1;
-                  gray16  =  (rc * red + gc * green + bc * blue)>>8;
-                  *(dp++) = (gray16>>8) & 0xff;
-                  *(dp++) = gray16 & 0xff;
+                  gray16  = (png_uint_16)((rc*red + gc*green + bc*blue)>>8);
+                  *(dp++) = (png_byte)((gray16>>8) & 0xff);
+                  *(dp++) = (png_byte)(gray16 & 0xff);
                }
             }
          }
@@ -2112,7 +2165,7 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                   png_byte blue  = *(sp++);
                   if(red != green || red != blue)
                      rgb_error |= 1;
-                  *(dp++) =  (gc*red + gc*green + bc*blue)>>8;
+                  *(dp++) =  (png_byte)((gc*red + gc*green + bc*blue)>>8);
                   *(dp++) = *(sp++);  /* alpha */
                }
             }
@@ -2129,9 +2182,9 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                {
                   png_uint_16 red, green, blue, w;
 
-                  red   = ((*(sp))<<8) | *(sp+1); sp+=2;
-                  green = ((*(sp))<<8) | *(sp+1); sp+=2;
-                  blue  = ((*(sp))<<8) | *(sp+1); sp+=2;
+                  red   = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)(((*(sp))<<8) | *(sp+1)); sp+=2;
 
                   if(red == green && red == blue)
                      w = red;
@@ -2143,15 +2196,15 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                                   png_ptr->gamma_shift][green>>8];
                      png_uint_16 blue_1  = png_ptr->gamma_16_to_1[(blue&0xff) >> 
                                   png_ptr->gamma_shift][blue>>8];
-                     png_uint_16 gray16  =  (rc * red_1 + gc * green_1
-                                  + bc * blue_1)>>8;
+                     png_uint_16 gray16  = (png_uint_16)((rc * red_1
+                                  + gc * green_1 + bc * blue_1)>>8);
                      w = png_ptr->gamma_16_from_1[(gray16&0xff) >>
                          png_ptr->gamma_shift][gray16 >> 8];
                      rgb_error |= 1;
                   }
                   
-                  *(dp++) = (w>>8) & 0xff;
-                  *(dp++) = w & 0xff;
+                  *(dp++) = (png_byte)((w>>8) & 0xff);
+                  *(dp++) = (png_byte)(w & 0xff);
                   *(dp++) = *(sp++);  /* alpha */
                   *(dp++) = *(sp++);
                }
@@ -2164,14 +2217,14 @@ png_do_rgb_to_gray(png_structp png_ptr, png_row_infop row_info, png_bytep row)
                for (i = 0; i < row_width; i++)
                {
                   png_uint_16 red, green, blue, gray16;
-                  red   = (*(sp)<<8) | *(sp+1); sp+=2;
-                  green = (*(sp)<<8) | *(sp+1); sp+=2;
-                  blue  = (*(sp)<<8) | *(sp+1); sp+=2;
+                  red   = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+                  green = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
+                  blue  = (png_uint_16)((*(sp)<<8) | *(sp+1)); sp+=2;
                   if(red != green || red != blue)
                      rgb_error |= 1;
-                  gray16  =  (rc * red + gc * green + bc * blue)>>8;
-                  *(dp++) = (gray16>>8) & 0xff;
-                  *(dp++) = gray16 & 0xff;
+                  gray16  = (png_uint_16)((rc*red + gc*green + bc*blue)>>8);
+                  *(dp++) = (png_byte)((gray16>>8) & 0xff);
+                  *(dp++) = (png_byte)(gray16 & 0xff);
                   *(dp++) = *(sp++);  /* alpha */
                   *(dp++) = *(sp++);
                }
@@ -2490,9 +2543,9 @@ png_do_background(png_row_infop row_info, png_bytep row,
                         }
                         else
                         {
-                           png_byte p = (*sp >> shift) & 0x3;
-                           png_byte g = (gamma_table [p | (p << 2) | (p << 4) |
-                               (p << 6)] >> 6) & 0x3;
+                           png_byte p = (png_byte)((*sp >> shift) & 0x3);
+                           png_byte g = (png_byte)((gamma_table [p | (p << 2) |
+                               (p << 4) | (p << 6)] >> 6) & 0x3);
                            *sp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
                            *sp |= (png_byte)(g << shift);
                         }
@@ -2546,8 +2599,9 @@ png_do_background(png_row_infop row_info, png_bytep row,
                         }
                         else
                         {
-                           png_byte p = (*sp >> shift) & 0xf;
-                           png_byte g = (gamma_table[p | (p << 4)] >> 4) & 0xf;
+                           png_byte p = (png_byte)((*sp >> shift) & 0xf);
+                           png_byte g = (png_byte)((gamma_table[p |
+                             (p << 4)] >> 4) & 0xf);
                            *sp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
                            *sp |= (png_byte)(g << shift);
                         }
@@ -2626,7 +2680,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
                      {
                         png_uint_16 v;
 
-                        v = ((png_uint_16)(*sp) << 8) + *(sp + 1);
+                        v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
                         if (v == trans_values->gray)
                         {
                            /* background is already in screen gamma */
@@ -2649,7 +2703,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
                      {
                         png_uint_16 v;
 
-                        v = ((png_uint_16)(*sp) << 8) + *(sp + 1);
+                        v = (png_uint_16)(((*sp) << 8) + *(sp + 1));
                         if (v == trans_values->gray)
                         {
                            *sp = (png_byte)((background->gray >> 8) & 0xff);
@@ -2713,9 +2767,9 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   sp = row;
                   for (i = 0; i < row_width; i++, sp += 6)
                   {
-                     png_uint_16 r = ((png_uint_16)(*sp) << 8) + *(sp + 1);
-                     png_uint_16 g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3);
-                     png_uint_16 b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5);
+                     png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                     png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+                     png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5));
                      if (r == trans_values->red && g == trans_values->green &&
                         b == trans_values->blue)
                      {
@@ -2747,9 +2801,9 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   sp = row;
                   for (i = 0; i < row_width; i++, sp += 6)
                   {
-                     png_uint_16 r = ((png_uint_16)(*sp) << 8) + *(sp + 1);
-                     png_uint_16 g = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3);
-                     png_uint_16 b = ((png_uint_16)(*(sp + 4)) << 8) + *(sp + 5);
+                     png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp+1));
+                     png_uint_16 g = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
+                     png_uint_16 b = (png_uint_16)(((*(sp+4)) << 8) + *(sp+5));
 
                      if (r == trans_values->red && g == trans_values->green &&
                         b == trans_values->blue)
@@ -2833,7 +2887,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   dp = row;
                   for (i = 0; i < row_width; i++, sp += 4, dp += 2)
                   {
-                     png_uint_16 a = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3);
+                     png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
 
                      if (a == (png_uint_16)0xffff)
                      {
@@ -2868,7 +2922,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
                   dp = row;
                   for (i = 0; i < row_width; i++, sp += 4, dp += 2)
                   {
-                     png_uint_16 a = ((png_uint_16)(*(sp + 2)) << 8) + *(sp + 3);
+                     png_uint_16 a = (png_uint_16)(((*(sp+2)) << 8) + *(sp+3));
                      if (a == (png_uint_16)0xffff)
                      {
                         png_memcpy(dp, sp, 2);
@@ -2882,7 +2936,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
                      {
                         png_uint_16 g, v;
 
-                        g = ((png_uint_16)(*sp) << 8) + *(sp + 1);
+                        g = (png_uint_16)(((*sp) << 8) + *(sp + 1));
                         png_composite_16(v, g, a, background_1->gray);
                         *dp = (png_byte)((v >> 8) & 0xff);
                         *(dp + 1) = (png_byte)(v & 0xff);
@@ -3051,11 +3105,11 @@ png_do_background(png_row_infop row_info, png_bytep row,
                      {
                         png_uint_16 v;
 
-                        png_uint_16 r = ((png_uint_16)(*sp) << 8) + *(sp + 1);
-                        png_uint_16 g = ((png_uint_16)(*(sp + 2)) << 8)
-                            + *(sp + 3);
-                        png_uint_16 b = ((png_uint_16)(*(sp + 4)) << 8)
-                            + *(sp + 5);
+                        png_uint_16 r = (png_uint_16)(((*sp) << 8) + *(sp + 1));
+                        png_uint_16 g = (png_uint_16)(((*(sp + 2)) << 8)
+                            + *(sp + 3));
+                        png_uint_16 b = (png_uint_16)(((*(sp + 4)) << 8)
+                            + *(sp + 5));
 
                         png_composite_16(v, r, a, background->red);
                         *dp = (png_byte)((v >> 8) & 0xff);
@@ -3090,7 +3144,7 @@ png_do_background(png_row_infop row_info, png_bytep row,
 #if defined(PNG_READ_GAMMA_SUPPORTED)
 /* Gamma correct the image, avoiding the alpha channel.  Make sure
  * you do this after you deal with the transparency issue on grayscale
- * or rgb images. If your bit depth is 8, use gamma_table, if it
+ * or RGB images. If your bit depth is 8, use gamma_table, if it
  * is 16, use gamma_16_table and gamma_shift.  Build these with
  * build_gamma_table().
  */
@@ -3224,10 +3278,11 @@ png_do_gamma(png_row_infop row_info, png_bytep row,
                   int c = *sp & 0x0c;
                   int d = *sp & 0x03;
 
-                  *sp = ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)])   ) & 0xc0)|
+                  *sp = (png_byte)(
+                        ((((int)gamma_table[a|(a>>2)|(a>>4)|(a>>6)])   ) & 0xc0)|
                         ((((int)gamma_table[(b<<2)|b|(b>>2)|(b>>4)])>>2) & 0x30)|
                         ((((int)gamma_table[(c<<4)|(c<<2)|c|(c>>2)])>>4) & 0x0c)|
-                        ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6)       );
+                        ((((int)gamma_table[(d<<6)|(d<<4)|(d<<2)|d])>>6) ));
                   sp++;
                }
             }
@@ -3239,8 +3294,8 @@ png_do_gamma(png_row_infop row_info, png_bytep row,
                   int msb = *sp & 0xf0;
                   int lsb = *sp & 0x0f;
 
-                  *sp = (((int)gamma_table[msb | (msb >> 4)]) & 0xf0) |
-                        (((int)gamma_table[(lsb << 4) | lsb]) >> 4);
+                  *sp = (png_byte)((((int)gamma_table[msb | (msb >> 4)]) & 0xf0)
+                          | (((int)gamma_table[(lsb << 4) | lsb]) >> 4));
                   sp++;
                }
             }
@@ -3272,7 +3327,7 @@ png_do_gamma(png_row_infop row_info, png_bytep row,
 #endif
 
 #if defined(PNG_READ_EXPAND_SUPPORTED)
-/* Expands a palette row to an rgb or rgba row depending
+/* Expands a palette row to an RGB or RGBA row depending
  * upon whether you supply trans and num_trans.
  */
 void
@@ -3434,7 +3489,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
    {
       if (row_info->color_type == PNG_COLOR_TYPE_GRAY)
       {
-         png_uint_16 gray = trans_value ? trans_value->gray : 0;
+         png_uint_16 gray = (png_uint_16)(trans_value ? trans_value->gray : 0);
 
          if (row_info->bit_depth < 8)
          {
@@ -3442,7 +3497,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
             {
                case 1:
                {
-                  gray *= 0xff;
+                  gray = (png_uint_16)(gray*0xff);
                   sp = row + (png_size_t)((row_width - 1) >> 3);
                   dp = row + (png_size_t)row_width - 1;
                   shift = 7 - (int)((row_width + 7) & 7);
@@ -3466,7 +3521,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
                }
                case 2:
                {
-                  gray *= 0x55;
+                  gray = (png_uint_16)(gray*0x55);
                   sp = row + (png_size_t)((row_width - 1) >> 2);
                   dp = row + (png_size_t)row_width - 1;
                   shift = (int)((3 - ((row_width + 3) & 3)) << 1);
@@ -3489,7 +3544,7 @@ png_do_expand(png_row_infop row_info, png_bytep row,
                }
                case 4:
                {
-                  gray *= 0x11;
+                  gray = (png_uint_16)(gray*0x11);
                   sp = row + (png_size_t)((row_width - 1) >> 1);
                   dp = row + (png_size_t)row_width - 1;
                   shift = (int)((1 - ((row_width + 1) & 1)) << 2);

pngrutil.c

@@ -1,11 +1,11 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  *
  * This file contains routines that are only called from within
  * libpng itself during the course of reading an image.
@@ -14,6 +14,10 @@
 #define PNG_INTERNAL
 #include "png.h"
 
+#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
+#include "pngasmrd.h"
+#endif
+
 #ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
 /* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
 png_uint_32
@@ -165,8 +169,8 @@ png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    interlace_type = buf[12];
 
    /* check for width and height valid values */
-   if (width == 0 || width > (png_uint_32)2147483647L || height == 0 ||
-        height > (png_uint_32)2147483647L)
+   if (width == 0 || width > PNG_MAX_UINT || height == 0 ||
+        height > PNG_MAX_UINT)
       png_error(png_ptr, "Invalid image size in IHDR");
 
    /* check other values */
@@ -178,7 +182,7 @@ png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       color_type == 5 || color_type > 6)
       png_error(png_ptr, "Invalid color type in IHDR");
 
-   if ((color_type == PNG_COLOR_TYPE_PALETTE && bit_depth) > 8 ||
+   if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
        ((color_type == PNG_COLOR_TYPE_RGB ||
          color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
          color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
@@ -420,7 +424,7 @@ png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
 #if defined(PNG_READ_sRGB_SUPPORTED)
    if (info_ptr->valid & PNG_INFO_sRGB)
-      if(igamma != (png_uint_32)45000L)
+      if(fabs((float)igamma - 45455.)>500.)
       {
          png_warning(png_ptr,
            "Ignoring incorrect gAMA value when sRGB is also present");
@@ -692,7 +696,7 @@ png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
 #if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
    if ((info_ptr->valid & PNG_INFO_gAMA))
-      if((png_uint_32)(png_ptr->gamma*(float)100000.+.5) != (png_uint_32)45000L)
+      if(fabs((png_ptr->gamma*(float)100000.+.5)-45455.) > 500.)
       {
          png_warning(png_ptr,
            "Ignoring incorrect gAMA value when sRGB is also present");
@@ -871,9 +875,21 @@ png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
    {
       png_ptr->background.index = buf[0];
-      png_ptr->background.red = (png_uint_16)png_ptr->palette[buf[0]].red;
-      png_ptr->background.green = (png_uint_16)png_ptr->palette[buf[0]].green;
-      png_ptr->background.blue = (png_uint_16)png_ptr->palette[buf[0]].blue;
+      if(info_ptr->num_palette)
+      {
+          if(buf[0] > info_ptr->num_palette)
+          {
+             png_warning(png_ptr, "Incorrect bKGD chunk index value");
+             png_crc_finish(png_ptr, length);
+             return;
+          }
+          png_ptr->background.red =
+             (png_uint_16)png_ptr->palette[buf[0]].red;
+          png_ptr->background.green =
+             (png_uint_16)png_ptr->palette[buf[0]].green;
+          png_ptr->background.blue =
+             (png_uint_16)png_ptr->palette[buf[0]].blue;
+      }
    }
    else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */
    {
@@ -929,7 +945,7 @@ png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
       return;
    }
 
-   num = (int)length / 2;
+   num = (int)length / 2 ;
    png_ptr->hist = (png_uint_16p)png_malloc(png_ptr,
       (png_uint_32)(num * sizeof (png_uint_16)));
    png_ptr->flags |= PNG_FLAG_FREE_HIST;
@@ -1247,6 +1263,7 @@ png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
    png_set_text(png_ptr, info_ptr, text_ptr, 1);
 
+   png_free(png_ptr, key);
    png_free(png_ptr, text_ptr);
 }
 #endif
@@ -1264,7 +1281,6 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
    png_size_t slength;
 
    png_debug(1, "in png_handle_zTXt\n");
-
    if (!(png_ptr->mode & PNG_HAVE_IHDR))
       png_error(png_ptr, "Missing IHDR before zTXt");
 
@@ -1416,6 +1432,7 @@ png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
 
    png_set_text(png_ptr, info_ptr, text_ptr, 1);
 
+   png_free(png_ptr, text_ptr->key);
    png_free(png_ptr, text_ptr);
 }
 #endif
@@ -1480,8 +1497,12 @@ png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name)
    to any alpha or transparency value associated with the pixel.  If
    you want all pixels to be combined, pass 0xff (255) in mask.  */
 void
-png_combine_row(png_structp png_ptr, png_bytep row,
-   int mask)
+#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
+png_combine_row_c
+#else
+png_combine_row
+#endif /* PNG_HAVE_ASSEMBLER_COMBINE_ROW */
+   (png_structp png_ptr, png_bytep row, int mask)
 {
    png_debug(1,"in png_combine_row\n");
    if (mask == 0xff)
@@ -1684,9 +1705,21 @@ png_combine_row(png_structp png_ptr, png_bytep row,
 
 #if defined(PNG_READ_INTERLACING_SUPPORTED)
 void
-png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
+#ifdef PNG_HAVE_ASSEMBLER_READ_INTERLACE
+png_do_read_interlace_c
+#else
+png_do_read_interlace
+#endif /* PNG_HAVE_ASSEMBLER_READ_INTERLACE */
+   (png_row_infop row_info, png_bytep row, int pass,
    png_uint_32 transformations)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* offset to next interlace block */
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+   
    png_debug(1,"in png_do_read_interlace\n");
    if (row != NULL && row_info != NULL)
    {
@@ -1867,6 +1900,7 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
             png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
             png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;
             png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
+
             int jstop = png_pass_inc[pass];
             png_uint_32 i;
 
@@ -1894,13 +1928,16 @@ png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
 #endif
 
 void
-png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
+#ifdef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
+png_read_filter_row_c
+#else
+png_read_filter_row
+#endif /* PNG_HAVE_ASSEMBLER_READ_FILTER_ROW */
+   (png_structp png_ptr, png_row_infop row_info, png_bytep row,
    png_bytep prev_row, int filter)
 {
    png_debug(1, "in png_read_filter_row\n");
    png_debug2(2,"row = %d, filter = %d\n", png_ptr->row_number, filter);
-
-
    switch (filter)
    {
       case PNG_FILTER_VALUE_NONE:
@@ -1909,7 +1946,7 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
       {
          png_uint_32 i;
          png_uint_32 istop = row_info->rowbytes;
-         png_uint_32 bpp = (row_info->pixel_depth + 7) / 8;
+         png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
          png_bytep rp = row + bpp;
          png_bytep lp = row;
 
@@ -1940,20 +1977,20 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
          png_bytep rp = row;
          png_bytep pp = prev_row;
          png_bytep lp = row;
-         png_uint_32 bpp = (row_info->pixel_depth + 7) / 8;
+         png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
          png_uint_32 istop = row_info->rowbytes - bpp;
 
          for (i = 0; i < bpp; i++)
          {
             *rp = (png_byte)(((int)(*rp) +
-               ((int)(*pp++) / 2)) & 0xff);
+               ((int)(*pp++) / 2 )) & 0xff);
             rp++;
          }
 
          for (i = 0; i < istop; i++)
          {
             *rp = (png_byte)(((int)(*rp) +
-               (int)(*pp++ + *lp++) / 2) & 0xff);
+               (int)(*pp++ + *lp++) / 2 ) & 0xff);
             rp++;
          }
          break;
@@ -1965,7 +2002,7 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
          png_bytep pp = prev_row;
          png_bytep lp = row;
          png_bytep cp = prev_row;
-         png_uint_32 bpp = (row_info->pixel_depth + 7) / 8;
+         png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
          png_uint_32 istop=row_info->rowbytes - bpp;
 
          for (i = 0; i < bpp; i++)
@@ -2021,6 +2058,22 @@ png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
 void
 png_read_finish_row(png_structp png_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* start of interlace block */
+   const int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+   
+   /* offset to next interlace block */
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+   
+   /* start of interlace block in the y direction */
+   const int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+   
+   /* offset to next interlace block in the y direction */
+   const int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+   
    png_debug(1, "in png_read_finish_row\n");
    png_ptr->row_number++;
    if (png_ptr->row_number < png_ptr->num_rows)
@@ -2061,6 +2114,9 @@ png_read_finish_row(png_structp png_ptr)
 
    if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
    {
+#ifdef PNG_USE_LOCAL_ARRAYS
+      PNG_IDAT;
+#endif
       char extra;
       int ret;
 
@@ -2081,7 +2137,7 @@ png_read_finish_row(png_structp png_ptr)
 
                png_reset_crc(png_ptr);
                png_crc_read(png_ptr, png_ptr->chunk_name, 4);
-               if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
+               if (png_memcmp(png_ptr->chunk_name, (png_bytep)png_IDAT, 4))
                   png_error(png_ptr, "Not enough image data");
 
             }
@@ -2124,6 +2180,22 @@ png_read_finish_row(png_structp png_ptr)
 void
 png_read_start_row(png_structp png_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* start of interlace block */
+   const int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+   
+   /* offset to next interlace block */
+   const int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+   
+   /* start of interlace block in the y direction */
+   const int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+   
+   /* offset to next interlace block in the y direction */
+   const int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+   
    int max_pixel_depth;
    png_uint_32 row_bytes;
 
@@ -2239,6 +2311,16 @@ png_read_start_row(png_structp png_ptr)
    }
 #endif
 
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   if(png_ptr->transformations & PNG_USER_TRANSFORM)
+     {
+       int user_pixel_depth=png_ptr->user_transform_depth*
+         png_ptr->user_transform_channels;
+       if(user_pixel_depth > max_pixel_depth)
+         max_pixel_depth=user_pixel_depth;
+     }
+#endif
+
    /* align the width on the next larger 8 pixels.  Mainly used
       for interlacing */
    row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7));

pngset.c

@@ -1,11 +1,11 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * 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
@@ -107,7 +107,7 @@ png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
 
    /* check for overflow */
    rowbytes_per_pixel = (info_ptr->pixel_depth + 7) >> 3;
-   if (( width > (png_uint_32)2147483647L/rowbytes_per_pixel))
+   if (( width > PNG_MAX_UINT/rowbytes_per_pixel))
    {
       png_warning(png_ptr,
          "Width too large to process image data; rowbytes will overflow.");
@@ -249,7 +249,7 @@ png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
    png_set_sRGB(png_ptr, info_ptr, intent);
 
 #if defined(PNG_READ_gAMA_SUPPORTED) || defined(PNG_WRITE_gAMA_SUPPORTED)
-   file_gamma = (float).45;
+   file_gamma = (float).45455;
    png_set_gAMA(png_ptr, info_ptr, file_gamma);
 #endif
 
@@ -317,9 +317,10 @@ png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
    for (i = 0; i < num_text; i++)
    {
       png_textp textp = &(info_ptr->text[info_ptr->num_text]);
+      png_charp key,text;
 
-      if (text_ptr[i].text == NULL)
-         text_ptr[i].text = (png_charp)"";
+      if (text_ptr[i].key == (png_charp)NULL)
+         continue;
 
       if (text_ptr[i].text[0] == '\0')
       {
@@ -331,8 +332,30 @@ png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
          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;
+      key=text_ptr[i].key;
+      for (text = key; *text++;)
+        /* empty loop to find the byte after the zero byte after the
+           end of key */ ;
+
+      textp->key = (png_charp)png_malloc(png_ptr,
+         (png_uint_32)(text+textp->text_length - key)+1);
+      /* Caution: the calling program, not libpng, is responsible for
+         freeing this, if libpng wasn't the caller. */
+      png_debug2(2, "Allocated %d bytes at %x in png_set_text\n",
+         text+textp->text_length-key+1, textp->key);
+
+      png_memcpy(textp->key, text_ptr[i].key,
+         (png_size_t)(text - key));  /* includes the zero-byte separator */
+      textp->text = textp->key + (text-key);
+      if(textp->text_length)
+      {
+         png_memcpy(textp->text, text_ptr[i].text,
+            (png_size_t)(textp->text_length));
+         *(textp->text+textp->text_length) = '\0';
+      }
+      else
+         textp->text--;
+      info_ptr->text[info_ptr->num_text]= *textp;
       info_ptr->num_text++;
       png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
    }
@@ -344,7 +367,8 @@ 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)
+   if (png_ptr == NULL || info_ptr == NULL ||
+       (png_ptr->mode & PNG_WROTE_tIME))
       return;
 
    png_memcpy(&(info_ptr->mod_time), mod_time, sizeof (png_time));
@@ -378,3 +402,13 @@ png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
 }
 #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

pngtest.c

@@ -1,11 +1,11 @@
 
 /* pngtest.c - a simple test program to test libpng
  *
- * libpng 1.0.2a -December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  *
  * This program reads in a PNG image, writes it out again, and then
  * compares the two files.  If the files are identical, this shows that
@@ -35,13 +35,31 @@
 #define PNG_DEBUG 0
 #endif
 
+/* Turn on CPU timing
+#define PNGTEST_TIMING
+*/
+
+#ifdef PNGTEST_TIMING
+static float t_start, t_stop, t_decode, t_encode, t_misc;
+#include <time.h>
+#endif
+
 #include "png.h"
 
+#ifdef PNGTEST_TIMING
+static float t_start, t_stop, t_decode, t_encode, t_misc;
+#if !defined(PNG_READ_tIME_SUPPORTED) && !defined(PNG_WRITE_tIME_SUPPORTED)
+#include <time.h>
+#endif
+#endif
+
 #if defined(PNG_TIME_RFC1123_SUPPORTED)
 static int tIME_chunk_present=0;
 static char tIME_string[30] = "no tIME chunk present in file";
 #endif /* PNG_TIME_RFC1123_SUPPORTED */
 
+static int verbose = 0;
+
 int test_one_file PNGARG((PNG_CONST char *inname, PNG_CONST char *outname));
 
 #ifdef __TURBOC__
@@ -60,12 +78,12 @@ static int status_dots=1;
 void
 read_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
 {
-    if(png_ptr == NULL || row_number > 0x3fffffffL) return;
+    if(png_ptr == NULL || row_number > PNG_MAX_UINT) return;
     if(status_pass != pass)
     {
        fprintf(stdout,"\n Pass %d: ",pass);
        status_pass = pass;
-       status_dots = 30;
+       status_dots = 31;
     }
     status_dots--;
     if(status_dots == 0)
@@ -79,11 +97,24 @@ read_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
 void
 write_row_callback(png_structp png_ptr, png_uint_32 row_number, int pass)
 {
-    if(png_ptr == NULL || row_number > 0x3fffffffL || pass > 7) return;
+    if(png_ptr == NULL || row_number > PNG_MAX_UINT || pass > 7) return;
     fprintf(stdout, "w");
 }
 
 
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+/* Example of using user transform callback (we don't transform anything,
+   but merely examine the row filters.  We set this to 256 rather than
+   5 in case illegal filter values are present.) */
+static png_uint_32 filters_used[256];
+void
+count_filters(png_structp png_ptr, png_row_infop row_info, png_bytep data)
+{
+    if(png_ptr != NULL && row_info != NULL)
+      ++filters_used[*(data-1)];
+}
+#endif
+
 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
 /* example of using user transform callback (we don't transform anything,
    but merely count the zero samples) */
@@ -105,6 +136,7 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
     *  png_byte pixel_depth   bits per pixel (depth*channels)
     */
 
+
     /* counts the number of zero samples (or zero pixels if color_type is 3 */
 
     if(row_info->color_type == 0 || row_info->color_type == 3)
@@ -178,7 +210,6 @@ count_zero_samples(png_structp png_ptr, png_row_infop row_info, png_bytep data)
 }
 #endif /* PNG_WRITE_USER_TRANSFORM_SUPPORTED */
 
-static int verbose = 0;
 static int wrote_question = 0;
 
 #if defined(PNG_NO_STDIO)
@@ -412,6 +443,10 @@ png_debug_malloc(png_structp png_ptr, png_uint_32 size) {
       pinformation = pinfo;
       /* Make sure the caller isn't assuming zeroed memory. */
       png_memset(pinfo->pointer, 0xdd, pinfo->size);
+#if PNG_DEBUG
+      if(verbose)
+         printf("png_malloc %d bytes at %x\n",size,pinfo->pointer);
+#endif
       return (png_voidp)(pinfo->pointer);
    }
 }
@@ -454,6 +489,10 @@ png_debug_free(png_structp png_ptr, png_voidp ptr)
    }
 
    /* Finally free the data. */
+#if PNG_DEBUG
+   if(verbose)
+      printf("Freeing %x\n",ptr);
+#endif
    png_free_default(png_ptr, ptr);
 }
 #endif /* PNG_USER_MEM_SUPPORTED */
@@ -465,7 +504,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 {
    static FILE *fpin, *fpout;  /* "static" prevents setjmp corruption */
    png_structp read_ptr, write_ptr;
-   png_infop read_info_ptr, write_info_ptr, end_info_ptr;
+   png_infop read_info_ptr, write_info_ptr, end_info_ptr, write_end_info_ptr;
    png_bytep row_buf;
    png_uint_32 y;
    png_uint_32 width, height;
@@ -521,6 +560,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    read_info_ptr = png_create_info_struct(read_ptr);
    write_info_ptr = png_create_info_struct(write_ptr);
    end_info_ptr = png_create_info_struct(read_ptr);
+   write_end_info_ptr = png_create_info_struct(write_ptr);
 #ifdef PNG_USER_MEM_SUPPORTED
 #endif
 
@@ -533,6 +573,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       fprintf(STDERR, "%s -> %s: libpng read error\n", inname, outname);
       png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
+      png_destroy_info_struct(write_ptr, &write_end_info_ptr);
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
       fclose(fpin);
       fclose(fpout);
@@ -551,6 +592,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       fprintf(STDERR, "%s -> %s: libpng write error\n", inname, outname);
       png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
+      png_destroy_info_struct(write_ptr, &write_end_info_ptr);
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
       fclose(fpin);
       fclose(fpout);
@@ -584,10 +626,18 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       png_set_read_status_fn(read_ptr, NULL);
    }
 
-#  if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-     zero_samples=0;
-     png_set_write_user_transform_fn(write_ptr, count_zero_samples);
-#  endif
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+   {
+     int i;
+     for(i=0; i<256; i++)
+        filters_used[i]=0;
+     png_set_read_user_transform_fn(read_ptr, count_filters);
+   }
+#endif
+#if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
+   zero_samples=0;
+   png_set_write_user_transform_fn(write_ptr, count_zero_samples);
+#endif
 
    png_debug(0, "Reading info struct\n");
    png_read_info(read_ptr, read_info_ptr);
@@ -735,16 +785,14 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
       if (png_get_tIME(read_ptr, read_info_ptr, &mod_time))
       {
          png_set_tIME(write_ptr, write_info_ptr, mod_time);
-      }
 #if defined(PNG_TIME_RFC1123_SUPPORTED)
-      {
          /* we have to use png_strcpy instead of "=" because the string
             pointed to by png_convert_to_rfc1123() gets free'ed before
             we use it */
          png_strcpy(tIME_string,png_convert_to_rfc1123(read_ptr, mod_time));
          tIME_chunk_present++;
-      }
 #endif /* PNG_TIME_RFC1123_SUPPORTED */
+      }
    }
 #endif
 #if defined(PNG_READ_tRNS_SUPPORTED) && defined(PNG_WRITE_tRNS_SUPPORTED)
@@ -763,6 +811,10 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 #endif
 
    png_debug(0, "\nWriting info struct\n");
+
+/* If we wanted, we could write info in two steps:
+   png_write_info_before_PLTE(write_ptr, write_info_ptr);
+ */
    png_write_info(write_ptr, write_info_ptr);
 
    png_debug(0, "\nAllocating row buffer \n");
@@ -772,6 +824,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    {
       fprintf(STDERR, "No memory to allocate row buffer\n");
       png_destroy_read_struct(&read_ptr, &read_info_ptr, (png_infopp)NULL);
+      png_destroy_info_struct(write_ptr, &write_end_info_ptr);
       png_destroy_write_struct(&write_ptr, &write_info_ptr);
       fclose(fpin);
       fclose(fpout);
@@ -779,22 +832,72 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    }
    png_debug(0, "Writing row data\n");
 
+#if defined(PNG_READ_INTERLACING_SUPPORTED) || \
+  defined(PNG_WRITE_INTERLACING_SUPPORTED)
    num_pass = png_set_interlace_handling(read_ptr);
    png_set_interlace_handling(write_ptr);
+#else
+   num_pass=1;
+#endif
 
+#ifdef PNGTEST_TIMING
+   t_stop = (float)clock();
+   t_misc += (t_stop - t_start);
+   t_start = t_stop;
+#endif
    for (pass = 0; pass < num_pass; pass++)
    {
       png_debug1(0, "Writing row data for pass %d\n",pass);
       for (y = 0; y < height; y++)
       {
          png_read_rows(read_ptr, (png_bytepp)&row_buf, (png_bytepp)NULL, 1);
+#ifdef PNGTEST_TIMING
+         t_stop = (float)clock();
+         t_decode += (t_stop - t_start);
+         t_start = t_stop;
+#endif
          png_write_rows(write_ptr, (png_bytepp)&row_buf, 1);
+#ifdef PNGTEST_TIMING
+         t_stop = (float)clock();
+         t_encode += (t_stop - t_start);
+         t_start = t_stop;
+#endif
       }
    }
 
    png_debug(0, "Reading and writing end_info data\n");
    png_read_end(read_ptr, end_info_ptr);
-   png_write_end(write_ptr, end_info_ptr);
+#if (defined(PNG_READ_tEXt_SUPPORTED) && defined(PNG_WRITE_tEXt_SUPPORTED)) || \
+    (defined(PNG_READ_zTXt_SUPPORTED) && defined(PNG_WRITE_zTXt_SUPPORTED))
+   {
+      png_textp text_ptr;
+      int num_text;
+
+      if (png_get_text(read_ptr, end_info_ptr, &text_ptr, &num_text) > 0)
+      {
+         png_debug1(0, "Handling %d tEXt/zTXt chunks\n", num_text);
+         png_set_text(write_ptr, write_end_info_ptr, text_ptr, num_text);
+      }
+   }
+#endif
+#if defined(PNG_READ_tIME_SUPPORTED) && defined(PNG_WRITE_tIME_SUPPORTED)
+   {
+      png_timep mod_time;
+
+      if (png_get_tIME(read_ptr, end_info_ptr, &mod_time))
+      {
+         png_set_tIME(write_ptr, write_end_info_ptr, mod_time);
+#if defined(PNG_TIME_RFC1123_SUPPORTED)
+         /* we have to use png_strcpy instead of "=" because the string
+            pointed to by png_convert_to_rfc1123() gets free'ed before
+            we use it */
+         png_strcpy(tIME_string,png_convert_to_rfc1123(read_ptr, mod_time));
+         tIME_chunk_present++;
+#endif /* PNG_TIME_RFC1123_SUPPORTED */
+      }
+   }
+#endif
+   png_write_end(write_ptr, write_end_info_ptr);
 
 #ifdef PNG_EASY_ACCESS_SUPPORTED
    if(verbose)
@@ -810,6 +913,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
    png_debug(0, "Destroying data structs\n");
    png_free(read_ptr, row_buf);
    png_destroy_read_struct(&read_ptr, &read_info_ptr, &end_info_ptr);
+   png_destroy_info_struct(write_ptr, &write_end_info_ptr);
    png_destroy_write_struct(&write_ptr, &write_info_ptr);
 
    fclose(fpin);
@@ -861,7 +965,7 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 
       if (png_memcmp(inbuf, outbuf, num_in))
       {
-         fprintf(STDERR, "Files %s and %s are different\n", inname, outname);
+         fprintf(STDERR, "\nFiles %s and %s are different\n", inname, outname);
          if(wrote_question == 0)
          {
             fprintf(STDERR,
@@ -887,8 +991,8 @@ test_one_file(PNG_CONST char *inname, PNG_CONST char *outname)
 
 /* input and output filenames */
 #ifdef RISCOS
-PNG_CONST char *inname = "pngtest/png";
-PNG_CONST char *outname = "pngout/png";
+static PNG_CONST char *inname = "pngtest/png";
+static PNG_CONST char *outname = "pngout/png";
 #else
 static PNG_CONST char *inname = "pngtest.png";
 static PNG_CONST char *outname = "pngout.png";
@@ -903,6 +1007,10 @@ main(int argc, char *argv[])
    fprintf(STDERR, "Testing libpng version %s\n", PNG_LIBPNG_VER_STRING);
    fprintf(STDERR, "   with zlib   version %s\n", ZLIB_VERSION);
    fprintf(STDERR,"%s",png_get_copyright(NULL));
+   /* Show the version of libpng used in building the library */
+   fprintf(STDERR," library:%s",png_get_header_version(NULL));
+   /* Show the version of libpng used in building the application */
+   fprintf(STDERR," pngtest:%s",PNG_HEADER_VERSION_STRING);
 
    /* Do some consistency checking on the memory allocation settings, I'm
       not sure this matters, but it is nice to know, the first of these
@@ -975,16 +1083,22 @@ main(int argc, char *argv[])
 #endif
       for (i=2; i<argc; ++i)
       {
-         int kerror;
+         int k, kerror;
          fprintf(STDERR, "Testing %s:",argv[i]);
          kerror = test_one_file(argv[i], outname);
          if (kerror == 0)
          {
 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-            fprintf(STDERR, " PASS (%lu zero samples)\n",zero_samples);
+            fprintf(STDERR, "\n PASS (%lu zero samples)\n",zero_samples);
 #else
             fprintf(STDERR, " PASS\n");
 #endif
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+            for (k=0; k<256; k++)
+               if(filters_used[k])
+                  fprintf(STDERR, " Filter %d was used %lu times\n",
+                     k,filters_used[k]);
+#endif
 #if defined(PNG_TIME_RFC1123_SUPPORTED)
          if(tIME_chunk_present != 0)
             fprintf(STDERR, " tIME = %s\n",tIME_string);
@@ -1013,7 +1127,9 @@ main(int argc, char *argv[])
 #endif
       }
 #ifdef PNG_USER_MEM_SUPPORTED
-         fprintf(STDERR, "Maximum memory allocation: %d bytes\n",
+         fprintf(STDERR, " Current memory allocation: %d bytes\n",
+            current_allocation);
+         fprintf(STDERR, " Maximum memory allocation: %d bytes\n",
             maximum_allocation);
 #endif
    }
@@ -1034,14 +1150,21 @@ main(int argc, char *argv[])
          {
             if(verbose == 1 || i == 2)
             {
+                int k;
 #if defined(PNG_WRITE_USER_TRANSFORM_SUPPORTED)
-                fprintf(STDERR, " PASS (%lu zero samples)\n",zero_samples);
+                fprintf(STDERR, "\n PASS (%lu zero samples)\n",zero_samples);
 #else
                 fprintf(STDERR, " PASS\n");
 #endif
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED)
+                for (k=0; k<256; k++)
+                   if(filters_used[k])
+                      fprintf(STDERR, " Filter %d was used %lu times\n",
+                         k,filters_used[k]);
+#endif
 #if defined(PNG_TIME_RFC1123_SUPPORTED)
-         if(tIME_chunk_present != 0)
-            fprintf(STDERR, " tIME = %s\n",tIME_string);
+             if(tIME_chunk_present != 0)
+                fprintf(STDERR, " tIME = %s\n",tIME_string);
 #endif /* PNG_TIME_RFC1123_SUPPORTED */
             }
          }
@@ -1069,11 +1192,27 @@ main(int argc, char *argv[])
 #endif
        }
 #ifdef PNG_USER_MEM_SUPPORTED
-       fprintf(STDERR, "Maximum memory allocation: %d bytes\n",
+       fprintf(STDERR, " Current memory allocation: %d bytes\n",
+          current_allocation);
+       fprintf(STDERR, " Maximum memory allocation: %d bytes\n",
           maximum_allocation);
 #endif
    }
 
+#ifdef PNGTEST_TIMING
+   t_stop = (float)clock();
+   t_misc += (t_stop - t_start);
+   t_start = t_stop;
+   fprintf(STDERR," CPU time used = %.3f seconds",
+      (t_misc+t_decode+t_encode)/(float)CLOCKS_PER_SEC);
+   fprintf(STDERR," (decoding %.3f,\n",
+      t_decode/(float)CLOCKS_PER_SEC);
+   fprintf(STDERR,"        encoding %.3f ,",
+      t_encode/(float)CLOCKS_PER_SEC);
+   fprintf(STDERR," other %.3f seconds)\n\n",
+      t_misc/(float)CLOCKS_PER_SEC);
+#endif
+
    if (ierror == 0)
       fprintf(STDERR, "libpng passes test\n");
    else
@@ -1081,3 +1220,10 @@ main(int argc, char *argv[])
    return (int)(ierror != 0);
 }
 
+/* Generate a compiler error if there is an old png.h in the search path. */
+void
+png_check_pngtest_version
+   (version_1_0_5d png_h_is_not_version_1_0_5d)
+{
+   if(png_h_is_not_version_1_0_5d == NULL) return;
+}

pngtrans.c

@@ -1,18 +1,18 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * 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)
 {
@@ -570,3 +570,26 @@ png_do_bgr(png_row_infop row_info, png_bytep row)
 }
 #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 = (png_byte)user_transform_depth;
+   png_ptr->user_transform_channels = (png_byte)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

pngtypes.h

@@ -0,0 +1,31 @@
+/* pngtypes.h - array of chunk-types for libpng
+ *
+ * libpng 1.0.5d - November 29, 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
+ */
+
+/* Constant strings for known chunk types.  If you need to add a chunk,
+ * define the string in png.h and invoke it here.
+ */
+
+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;
+

pngwio.c

@@ -1,11 +1,11 @@
 
 /* pngwio.c - functions for data output
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * 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

pngwrite.c

@@ -1,11 +1,11 @@
 
 /* pngwrite.c - general routines to write a PNG file
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  */
 
 /* get internal access to png.h */
@@ -22,13 +22,11 @@
  * them in png_write_end(), and compressing them.
  */
 void
-png_write_info(png_structp png_ptr, png_infop info_ptr)
+png_write_info_before_PLTE(png_structp png_ptr, png_infop info_ptr)
 {
-#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
-   int i;
-#endif
-
-   png_debug(1, "in png_write_info\n");
+   png_debug(1, "in png_write_info_before_PLTE\n");
+   if (!(png_ptr->mode & PNG_WROTE_INFO_BEFORE_PLTE))
+   {
    png_write_sig(png_ptr); /* write PNG signature */
    /* write IHDR information. */
    png_write_IHDR(png_ptr, info_ptr->width, info_ptr->height,
@@ -61,6 +59,21 @@ png_write_info(png_structp png_ptr, png_infop info_ptr)
          info_ptr->x_green, info_ptr->y_green,
          info_ptr->x_blue, info_ptr->y_blue);
 #endif
+      png_ptr->mode |= PNG_WROTE_INFO_BEFORE_PLTE;
+   }
+}
+
+void
+png_write_info(png_structp png_ptr, png_infop info_ptr)
+{
+#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
+   int i;
+#endif
+
+   png_debug(1, "in png_write_info\n");
+
+   png_write_info_before_PLTE(png_ptr, info_ptr);
+
    if (info_ptr->valid & PNG_INFO_PLTE)
       png_write_PLTE(png_ptr, info_ptr->palette,
          (png_uint_32)info_ptr->num_palette);
@@ -77,7 +90,7 @@ png_write_info(png_structp png_ptr, png_infop info_ptr)
          {
             int j;
             for (j=0; j<(int)info_ptr->num_trans; j++)
-               info_ptr->trans[j] = 255 - info_ptr->trans[j];
+               info_ptr->trans[j] = (png_byte)(255 - info_ptr->trans[j]);
          }
 #endif
       png_write_tRNS(png_ptr, info_ptr->trans, &(info_ptr->trans_values),
@@ -112,7 +125,7 @@ png_write_info(png_structp png_ptr, png_infop info_ptr)
    if (info_ptr->valid & PNG_INFO_tIME)
    {
       png_write_tIME(png_ptr, &(info_ptr->mod_time));
-      png_ptr->flags |= PNG_FLAG_WROTE_tIME;
+      png_ptr->mode |= PNG_WROTE_tIME;
    }
 #endif
 #if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
@@ -172,7 +185,7 @@ png_write_end(png_structp png_ptr, png_infop info_ptr)
 #if defined(PNG_WRITE_tIME_SUPPORTED)
       /* check to see if user has supplied a time chunk */
       if (info_ptr->valid & PNG_INFO_tIME &&
-         !(png_ptr->flags & PNG_FLAG_WROTE_tIME))
+         !(png_ptr->mode & PNG_WROTE_tIME))
          png_write_tIME(png_ptr, &(info_ptr->mod_time));
 #endif
 #if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_zTXt_SUPPORTED)
@@ -630,8 +643,22 @@ png_destroy_write_struct(png_structpp png_ptr_ptr, png_infopp info_ptr_ptr)
 
    if (info_ptr != NULL)
    {
-#ifdef PNG_WRITE_tEXt_SUPPORTED
+#if defined(PNG_WRITE_tEXt_SUPPORTED) || defined(PNG_WRITE_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++)
+      {
+         if(info_ptr->text[i].key != NULL)
+         {
+           png_free(png_ptr, info_ptr->text[i].key);
+           info_ptr->text[i].key = NULL;
+         }
+      }
       png_free(png_ptr, info_ptr->text);
+      info_ptr->text = NULL;
+   }
 #endif
 #if defined(PNG_READ_pCAL_SUPPORTED)
       png_free(png_ptr, info_ptr->pcal_purpose);
@@ -799,7 +826,7 @@ png_set_filter(png_structp png_ptr, int method, int filters)
             if (png_ptr->prev_row == NULL)
             {
                png_warning(png_ptr, "Can't add Paeth filter after starting");
-               png_ptr->do_filter &= ~PNG_FILTER_PAETH;
+               png_ptr->do_filter &= (png_byte)(~PNG_FILTER_PAETH);
             }
             else
             {
@@ -850,8 +877,8 @@ png_set_filter_heuristics(png_structp png_ptr, int heuristic_method,
       num_weights = 0;
    }
 
-   png_ptr->num_prev_filters = num_weights;
-   png_ptr->heuristic_method = heuristic_method;
+   png_ptr->num_prev_filters = (png_byte)num_weights;
+   png_ptr->heuristic_method = (png_byte)heuristic_method;
 
    if (num_weights > 0)
    {
@@ -971,6 +998,8 @@ png_set_compression_window_bits(png_structp png_ptr, int window_bits)
 {
    if (window_bits > 15)
       png_warning(png_ptr, "Only compression windows <= 32k supported by PNG");
+   else if (window_bits < 8)
+      png_warning(png_ptr, "Only compression windows >= 256 supported by PNG");
    png_ptr->flags |= PNG_FLAG_ZLIB_CUSTOM_WINDOW_BITS;
    png_ptr->zlib_window_bits = window_bits;
 }
@@ -1001,4 +1030,3 @@ png_set_write_user_transform_fn(png_structp png_ptr, png_user_transform_ptr
    png_ptr->write_user_transform_fn = write_user_transform_fn;
 }
 #endif
-

pngwtran.c

@@ -1,11 +1,11 @@
 
 /* pngwtran.c - transforms the data in a row for PNG writers
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  */
 
 #define PNG_INTERNAL
@@ -311,7 +311,7 @@ png_do_shift(png_row_infop row_info, png_bytep row, png_color_8p bit_depth)
             png_uint_16 value, v;
             int j;
 
-            v = ((png_uint_16)(*bp) << 8) + *(bp + 1);
+            v = (png_uint_16)(((png_uint_16)(*bp) << 8) + *(bp + 1));
             value = 0;
             for (j = shift_start[c]; j > -shift_dec[c]; j -= shift_dec[c])
             {
@@ -438,7 +438,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = *(sp++);
                *(dp++) = *(sp++);
                *(dp++) = *(sp++);
-               *(dp++) = 255 - *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
          /* This inverts the alpha channel in RRGGBBAA */
@@ -456,8 +456,8 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
                *(dp++) = *(sp++);
                *(dp++) = *(sp++);
                *(dp++) = *(sp++);
-               *(dp++) = 255 - *(sp++);
-               *(dp++) = 255 - *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
+               *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
       }
@@ -473,7 +473,7 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
             for (i = 0, sp = dp = row; i < row_width; i++)
             {
                *(dp++) = *(sp++);
-               *(dp++) = 255 - *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
          /* This inverts the alpha channel in GGAA */
@@ -487,8 +487,8 @@ png_do_write_invert_alpha(png_row_infop row_info, png_bytep row)
             {
                *(dp++) = *(sp++);
                *(dp++) = *(sp++);
-               *(dp++) = 255 - *(sp++);
-               *(dp++) = 255 - *(sp++);
+               *(dp++) = (png_byte)(255 - *(sp++));
+               *(dp++) = (png_byte)(255 - *(sp++));
             }
          }
       }

pngwutil.c

@@ -1,11 +1,11 @@
 
 /* pngwutil.c - utilities to write a PNG file
  *
- * libpng 1.0.2a - December 29, 1998
+ * libpng 1.0.5d - November 29, 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, Glenn Randers-Pehrson
+ * Copyright (c) 1998, 1999 Glenn Randers-Pehrson
  */
 
 #define PNG_INTERNAL
@@ -127,8 +127,9 @@ png_write_chunk_end(png_structp png_ptr)
 void
 png_write_sig(png_structp png_ptr)
 {
+   png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
    /* write the rest of the 8 byte signature */
-   png_write_data(png_ptr, &png_sig[png_ptr->sig_bytes],
+   png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
       (png_size_t)8 - png_ptr->sig_bytes);
 }
 
@@ -141,6 +142,9 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
    int bit_depth, int color_type, int compression_type, int filter_type,
    int interlace_type)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IHDR;
+#endif
    png_byte buf[13]; /* buffer to store the IHDR info */
 
    png_debug(1, "in png_write_IHDR\n");
@@ -234,7 +238,7 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
    buf[12] = (png_byte)interlace_type;
 
    /* write the chunk */
-   png_write_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
+   png_write_chunk(png_ptr, (png_bytep)png_IHDR, buf, (png_size_t)13);
 
    /* initialize zlib with PNG info */
    png_ptr->zstream.zalloc = png_zalloc;
@@ -279,28 +283,35 @@ png_write_IHDR(png_structp png_ptr, png_uint_32 width, png_uint_32 height,
 void
 png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_PLTE;
+#endif
    png_uint_32 i;
    png_colorp pal_ptr;
    png_byte buf[3];
 
    png_debug(1, "in png_write_PLTE\n");
-   if (num_pal == 0 || num_pal > 256)
-   {
-      if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-      {
-         png_error(png_ptr, "Invalid number of colors in palette");
-      }
-      else
-      {
-         png_warning(png_ptr, "Invalid number of colors in palette");
-         return;
-      }
+   if ((
+#ifdef PNG_WRITE_EMPTY_PLTE_SUPPORTED
+        !png_ptr->empty_plte_permitted &&
+#endif
+        num_pal == 0) || num_pal > 256)
+     {
+       if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+         {
+           png_error(png_ptr, "Invalid number of colors in palette");
+         }
+       else
+         {
+           png_warning(png_ptr, "Invalid number of colors in palette");
+           return;
+         }
    }
 
    png_ptr->num_palette = (png_uint_16)num_pal;
    png_debug1(3, "num_palette = %d\n", png_ptr->num_palette);
 
-   png_write_chunk_start(png_ptr, png_PLTE, num_pal * 3);
+   png_write_chunk_start(png_ptr, (png_bytep)png_PLTE, num_pal * 3);
    for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
    {
       buf[0] = pal_ptr->red;
@@ -316,8 +327,11 @@ png_write_PLTE(png_structp png_ptr, png_colorp palette, png_uint_32 num_pal)
 void
 png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IDAT;
+#endif
    png_debug(1, "in png_write_IDAT\n");
-   png_write_chunk(png_ptr, png_IDAT, data, length);
+   png_write_chunk(png_ptr, (png_bytep)png_IDAT, data, length);
    png_ptr->mode |= PNG_HAVE_IDAT;
 }
 
@@ -325,8 +339,11 @@ png_write_IDAT(png_structp png_ptr, png_bytep data, png_size_t length)
 void
 png_write_IEND(png_structp png_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_IEND;
+#endif
    png_debug(1, "in png_write_IEND\n");
-   png_write_chunk(png_ptr, png_IEND, NULL, (png_size_t)0);
+   png_write_chunk(png_ptr, (png_bytep)png_IEND, NULL, (png_size_t)0);
    png_ptr->mode |= PNG_HAVE_IEND;
 }
 
@@ -335,6 +352,9 @@ png_write_IEND(png_structp png_ptr)
 void
 png_write_gAMA(png_structp png_ptr, double file_gamma)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_gAMA;
+#endif
    png_uint_32 igamma;
    png_byte buf[4];
 
@@ -342,7 +362,7 @@ png_write_gAMA(png_structp png_ptr, double file_gamma)
    /* file_gamma is saved in 1/1000000ths */
    igamma = (png_uint_32)(file_gamma * 100000.0 + 0.5);
    png_save_uint_32(buf, igamma);
-   png_write_chunk(png_ptr, png_gAMA, buf, (png_size_t)4);
+   png_write_chunk(png_ptr, (png_bytep)png_gAMA, buf, (png_size_t)4);
 }
 #endif
 
@@ -351,6 +371,9 @@ png_write_gAMA(png_structp png_ptr, double file_gamma)
 void
 png_write_sRGB(png_structp png_ptr, int srgb_intent)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sRGB;
+#endif
    png_byte buf[1];
 
    png_debug(1, "in png_write_sRGB\n");
@@ -358,7 +381,7 @@ png_write_sRGB(png_structp png_ptr, int srgb_intent)
          png_warning(png_ptr,
             "Invalid sRGB rendering intent specified");
    buf[0]=(png_byte)srgb_intent;
-   png_write_chunk(png_ptr, png_sRGB, buf, (png_size_t)1);
+   png_write_chunk(png_ptr, (png_bytep)png_sRGB, buf, (png_size_t)1);
 }
 #endif
 
@@ -367,6 +390,9 @@ png_write_sRGB(png_structp png_ptr, int srgb_intent)
 void
 png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_sBIT;
+#endif
    png_byte buf[4];
    png_size_t size;
 
@@ -376,7 +402,8 @@ png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
    {
       png_byte maxbits;
 
-      maxbits = color_type==PNG_COLOR_TYPE_PALETTE ? 8 : png_ptr->usr_bit_depth;
+      maxbits = (png_byte)(color_type==PNG_COLOR_TYPE_PALETTE ? 8 :
+                png_ptr->usr_bit_depth);
       if (sbit->red == 0 || sbit->red > maxbits ||
           sbit->green == 0 || sbit->green > maxbits ||
           sbit->blue == 0 || sbit->blue > maxbits)
@@ -410,7 +437,7 @@ png_write_sBIT(png_structp png_ptr, png_color_8p sbit, int color_type)
       buf[size++] = sbit->alpha;
    }
 
-   png_write_chunk(png_ptr, png_sBIT, buf, size);
+   png_write_chunk(png_ptr, (png_bytep)png_sBIT, buf, size);
 }
 #endif
 
@@ -421,6 +448,9 @@ png_write_cHRM(png_structp png_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)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_cHRM;
+#endif
    png_uint_32 itemp;
    png_byte buf[32];
 
@@ -470,7 +500,7 @@ png_write_cHRM(png_structp png_ptr, double white_x, double white_y,
    itemp = (png_uint_32)(blue_y * 100000.0 + 0.5);
    png_save_uint_32(buf + 28, itemp);
 
-   png_write_chunk(png_ptr, png_cHRM, buf, (png_size_t)32);
+   png_write_chunk(png_ptr, (png_bytep)png_cHRM, buf, (png_size_t)32);
 }
 #endif
 
@@ -480,6 +510,9 @@ void
 png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
    int num_trans, int color_type)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_tRNS;
+#endif
    png_byte buf[6];
 
    png_debug(1, "in png_write_tRNS\n");
@@ -491,13 +524,13 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
          return;
       }
       /* write the chunk out as it is */
-      png_write_chunk(png_ptr, png_tRNS, trans, (png_size_t)num_trans);
+      png_write_chunk(png_ptr, (png_bytep)png_tRNS, trans, (png_size_t)num_trans);
    }
    else if (color_type == PNG_COLOR_TYPE_GRAY)
    {
       /* one 16 bit value */
       png_save_uint_16(buf, tran->gray);
-      png_write_chunk(png_ptr, png_tRNS, buf, (png_size_t)2);
+      png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)2);
    }
    else if (color_type == PNG_COLOR_TYPE_RGB)
    {
@@ -505,7 +538,7 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
       png_save_uint_16(buf, tran->red);
       png_save_uint_16(buf + 2, tran->green);
       png_save_uint_16(buf + 4, tran->blue);
-      png_write_chunk(png_ptr, png_tRNS, buf, (png_size_t)6);
+      png_write_chunk(png_ptr, (png_bytep)png_tRNS, buf, (png_size_t)6);
    }
    else
    {
@@ -519,30 +552,38 @@ png_write_tRNS(png_structp png_ptr, png_bytep trans, png_color_16p tran,
 void
 png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_bKGD;
+#endif
    png_byte buf[6];
 
    png_debug(1, "in png_write_bKGD\n");
    if (color_type == PNG_COLOR_TYPE_PALETTE)
    {
-      if (back->index > png_ptr->num_palette)
+      if (
+#ifdef PNG_WRITE_EMPTY_PLTE_SUPPORTED
+          (!png_ptr->empty_plte_permitted ||
+          (png_ptr->empty_plte_permitted && png_ptr->num_palette)) &&
+#endif
+         back->index > png_ptr->num_palette)
       {
          png_warning(png_ptr, "Invalid background palette index");
          return;
       }
       buf[0] = back->index;
-      png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)1);
+      png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)1);
    }
    else if (color_type & PNG_COLOR_MASK_COLOR)
    {
       png_save_uint_16(buf, back->red);
       png_save_uint_16(buf + 2, back->green);
       png_save_uint_16(buf + 4, back->blue);
-      png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)6);
+      png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)6);
    }
    else
    {
       png_save_uint_16(buf, back->gray);
-      png_write_chunk(png_ptr, png_bKGD, buf, (png_size_t)2);
+      png_write_chunk(png_ptr, (png_bytep)png_bKGD, buf, (png_size_t)2);
    }
 }
 #endif
@@ -552,6 +593,9 @@ png_write_bKGD(png_structp png_ptr, png_color_16p back, int color_type)
 void
 png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_hIST;
+#endif
    int i;
    png_byte buf[3];
 
@@ -564,7 +608,7 @@ png_write_hIST(png_structp png_ptr, png_uint_16p hist, int num_hist)
       return;
    }
 
-   png_write_chunk_start(png_ptr, png_hIST, (png_uint_32)(num_hist * 2));
+   png_write_chunk_start(png_ptr, (png_bytep)png_hIST, (png_uint_32)(num_hist * 2));
    for (i = 0; i < num_hist; i++)
    {
       png_save_uint_16(buf, hist[i]);
@@ -678,6 +722,8 @@ png_check_keyword(png_structp png_ptr, png_charp key, png_charpp new_key)
 
    if (key_len == 0)
    {
+      png_free(png_ptr, *new_key);
+      *new_key=NULL;
       png_chunk_warning(png_ptr, "zero length keyword");
    }
 
@@ -698,6 +744,9 @@ void
 png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
    png_size_t text_len)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_tEXt;
+#endif
    png_size_t key_len;
    png_charp new_key;
 
@@ -712,7 +761,12 @@ png_write_tEXt(png_structp png_ptr, png_charp key, png_charp text,
       text_len = 0;
 
    /* make sure we include the 0 after the key */
-   png_write_chunk_start(png_ptr, png_tEXt, (png_uint_32)key_len+text_len+1);
+   png_write_chunk_start(png_ptr, (png_bytep)png_tEXt, (png_uint_32)key_len+text_len+1);
+   /*
+    * We leave it to the application to meet PNG-1.0 requirements on the
+    * contents of the text.  PNG-1.0 through PNG-1.2 discourage the use of
+    * any non-Latin-1 characters except for NEWLINE.  ISO PNG will forbid them.
+    */
    png_write_chunk_data(png_ptr, (png_bytep)new_key, key_len + 1);
    if (text_len)
       png_write_chunk_data(png_ptr, (png_bytep)text, text_len);
@@ -728,6 +782,9 @@ void
 png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
    png_size_t text_len, int compression)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_zTXt;
+#endif
    png_size_t key_len;
    char buf[1];
    png_charp new_key;
@@ -897,7 +954,7 @@ png_write_zTXt(png_structp png_ptr, png_charp key, png_charp text,
       text_len += png_ptr->zbuf_size - (png_size_t)png_ptr->zstream.avail_out;
 
    /* write start of chunk */
-   png_write_chunk_start(png_ptr, png_zTXt, (png_uint_32)(key_len+text_len+2));
+   png_write_chunk_start(png_ptr, (png_bytep)png_zTXt, (png_uint_32)(key_len+text_len+2));
    /* write key */
    png_write_chunk_data(png_ptr, (png_bytep)key, key_len + 1);
    buf[0] = (png_byte)compression;
@@ -932,6 +989,9 @@ png_write_oFFs(png_structp png_ptr, png_uint_32 x_offset,
    png_uint_32 y_offset,
    int unit_type)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_oFFs;
+#endif
    png_byte buf[9];
 
    png_debug(1, "in png_write_oFFs\n");
@@ -942,7 +1002,7 @@ png_write_oFFs(png_structp png_ptr, png_uint_32 x_offset,
    png_save_uint_32(buf + 4, y_offset);
    buf[8] = (png_byte)unit_type;
 
-   png_write_chunk(png_ptr, png_oFFs, buf, (png_size_t)9);
+   png_write_chunk(png_ptr, (png_bytep)png_oFFs, buf, (png_size_t)9);
 }
 #endif
 
@@ -952,6 +1012,9 @@ void
 png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
    png_int_32 X1, int type, int nparams, png_charp units, png_charpp params)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_pCAL;
+#endif
    png_size_t purpose_len, units_len, total_len;
    png_uint_32p params_len;
    png_byte buf[10];
@@ -981,7 +1044,7 @@ png_write_pCAL(png_structp png_ptr, png_charp purpose, png_int_32 X0,
    }
 
    png_debug1(3, "pCAL total length = %d\n", total_len);
-   png_write_chunk_start(png_ptr, png_pCAL, (png_uint_32)total_len);
+   png_write_chunk_start(png_ptr, (png_bytep)png_pCAL, (png_uint_32)total_len);
    png_write_chunk_data(png_ptr, (png_bytep)new_purpose, purpose_len);
    png_save_int_32(buf, X0);
    png_save_int_32(buf + 4, X1);
@@ -1010,6 +1073,9 @@ png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
    png_uint_32 y_pixels_per_unit,
    int unit_type)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_pHYs;
+#endif
    png_byte buf[9];
 
    png_debug(1, "in png_write_pHYs\n");
@@ -1020,7 +1086,7 @@ png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
    png_save_uint_32(buf + 4, y_pixels_per_unit);
    buf[8] = (png_byte)unit_type;
 
-   png_write_chunk(png_ptr, png_pHYs, buf, (png_size_t)9);
+   png_write_chunk(png_ptr, (png_bytep)png_pHYs, buf, (png_size_t)9);
 }
 #endif
 
@@ -1031,6 +1097,9 @@ png_write_pHYs(png_structp png_ptr, png_uint_32 x_pixels_per_unit,
 void
 png_write_tIME(png_structp png_ptr, png_timep mod_time)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   PNG_tIME;
+#endif
    png_byte buf[7];
 
    png_debug(1, "in png_write_tIME\n");
@@ -1049,7 +1118,7 @@ png_write_tIME(png_structp png_ptr, png_timep mod_time)
    buf[5] = mod_time->minute;
    buf[6] = mod_time->second;
 
-   png_write_chunk(png_ptr, png_tIME, buf, (png_size_t)7);
+   png_write_chunk(png_ptr, (png_bytep)png_tIME, buf, (png_size_t)7);
 }
 #endif
 
@@ -1057,6 +1126,22 @@ png_write_tIME(png_structp png_ptr, png_timep mod_time)
 void
 png_write_start_row(png_structp png_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* start of interlace block */
+   int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+   
+   /* offset to next interlace block */
+   int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+   
+   /* start of interlace block in the y direction */
+   int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+   
+   /* offset to next interlace block in the y direction */
+   int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+   
    png_size_t buf_size;
 
    png_debug(1, "in png_write_start_row\n");
@@ -1135,6 +1220,22 @@ png_write_start_row(png_structp png_ptr)
 void
 png_write_finish_row(png_structp png_ptr)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* start of interlace block */
+   int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+   
+   /* offset to next interlace block */
+   int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+   
+   /* start of interlace block in the y direction */
+   int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
+   
+   /* offset to next interlace block in the y direction */
+   int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
+#endif
+   
    int ret;
 
    png_debug(1, "in png_write_finish_row\n");
@@ -1233,6 +1334,16 @@ png_write_finish_row(png_structp png_ptr)
 void
 png_do_write_interlace(png_row_infop row_info, png_bytep row, int pass)
 {
+#ifdef PNG_USE_LOCAL_ARRAYS
+   /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */
+   
+   /* start of interlace block */
+   int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
+   
+   /* offset to next interlace block */
+   int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
+#endif
+   
    png_debug(1, "in png_do_write_interlace\n");
    /* we don't have to do anything on the last pass (6) */
 #if defined(PNG_USELESS_TESTS_SUPPORTED)

scripts/makefile.aco

@@ -1,51 +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 -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.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

scripts/makefile.beos

@@ -0,0 +1,104 @@
+# makefile for libpng on BeOS x86 ELF with gcc
+# modified from makefile.linux 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 = 1.0.5d
+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

@@ -2,8 +2,8 @@
 # Borland C++ 4.5 (Note: All modules are compiled in C mode)
 # Will work with C++ 4.02 also
 # To build the library, do: 
-#       "make -fmakefile.bor -DMODEL=m"
-# or:   "make -fmakefile.bor -DMODEL=l"
+#       "make -fmakefile.borland -DMODEL=m"
+# or:   "make -fmakefile.borland -DMODEL=l"
 #
 # ------------- Borland C++ 4.5 -------------
 
@@ -70,38 +70,38 @@ O=obj
 
 ## variables
 OBJS = \
- 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.$(O)
+	png.$(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.$(O) \
- +pngset.$(O) \
- +pngget.$(O) \
- +pngrio.$(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
 
@@ -146,7 +146,7 @@ pngwutil.obj: pngwutil.c
 
 $(LIBNAME): $(OBJS)
 	-del $(LIBNAME)
-        $(LIB) $(LIBNAME) @&&|
+	$(LIB) $(LIBNAME) @&&|
 $(LIBOBJS), libpng$(MODEL)
 |
 

scripts/makefile.dec

@@ -14,7 +14,7 @@ ZLIBINC=../zlib
 # read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
 # have to change it.
 PNGMAJ = 2
-PNGMIN = 1.0.2a
+PNGMIN = 1.0.5d
 PNGVER = $(PNGMAJ).$(PNGMIN)
 
 CC=cc
@@ -36,10 +36,10 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 libpng.so: libpng.so.$(PNGMAJ)
-	ln -s -f libpng.so.$(PNGMAJ) libpng.so
+	ln -f -s libpng.so.$(PNGMAJ) libpng.so
 
 libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
-	ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+	ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
 
 libpng.so.$(PNGVER): $(OBJS)
 	$(CC) -shared -o $@ $(OBJS) -L$(ZLIBLIB) -lz -lm
@@ -62,8 +62,8 @@ install: libpng.a libpng.so.$(PNGVER)
 	chmod 644 $(prefix)/lib/libpng.a
 	chmod 644 $(prefix)/lib/libpng.so.$(PNGVER)
 	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
-	(cd $(LIBPATH); ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
-	 ln -s -f libpng.so.$(PNGMAJ) 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*

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 +2,11 @@
 # Copyright (C) 1995 Guy Eric Schalnat, Group 42, Inc.
 # For conditions of distribution and use, see copyright notice in png.h
 
+# This makefile requires the 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
 

scripts/makefile.linux

@@ -1,11 +1,11 @@
 # makefile for libpng on Linux ELF with gcc
 # Copyright (C) 1996, 1997 Andreas Dilger
-# Copyright (C) 1998 Greg Roelofs
+# 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*, and png.h
+# 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
@@ -15,15 +15,17 @@ ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
 ALIGN=
-# For I-386:
+# 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
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+
+# for pgcc version 2.95.1, -O3 is buggy; don't use it.
 
 CFLAGS=-I$(ZLIBINC) -Wall -O3 -funroll-loops \
-     $(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
+	$(ALIGN) # $(WARNMORE) -g -DPNG_DEBUG=5
 LDFLAGS=-L. -Wl,-rpath,. -L$(ZLIBLIB) -Wl,-rpath,$(ZLIBLIB) -lpng -lz -lm
 
 RANLIB=ranlib
@@ -32,15 +34,15 @@ RANLIB=ranlib
 # read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
 # have to change it.
 PNGMAJ = 2
-PNGMIN = 1.0.2a
+PNGMIN = 1.0.5d
 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
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -56,10 +58,10 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 libpng.so: libpng.so.$(PNGMAJ)
-	ln -s -f libpng.so.$(PNGMAJ) libpng.so
+	ln -sf libpng.so.$(PNGMAJ) libpng.so
 
 libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
-	ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+	ln -sf libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
 
 libpng.so.$(PNGVER): $(OBJSDLL)
 	$(CC) -shared -Wl,-soname,libpng.so.$(PNGMAJ) -o libpng.so.$(PNGVER) \
@@ -78,8 +80,8 @@ install: libpng.a libpng.so.$(PNGVER)
 	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
 	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
 	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
-	(cd $(LIBPATH); ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
-	 ln -s -f libpng.so.$(PNGMAJ) 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

scripts/makefile.msc

@@ -3,7 +3,7 @@
 # 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
 
-# ------------- Microsoft C 5.1 and later -------------
+# -------- Microsoft C 5.1 and later, does not use assembler code -----
 MODEL=-AL
 CFLAGS=-Oait -Gs -nologo -W3 $(MODEL) -I..\zlib
 #-Ox generates bad code with MSC 5.1
@@ -26,52 +26,52 @@ png$(O): png.h pngconf.h
 		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngset$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngget$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(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) $(OBJS3)
-        del libpng.lib
+	del libpng.lib
 	lib libpng $(OBJS1);
 	lib libpng $(OBJS2);
 	lib libpng $(OBJS3);

scripts/makefile.os2

@@ -10,10 +10,10 @@ ZLIBLIB=../zlib
 ZLIBINC=../zlib
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
-         -Wmissing-declarations -Wtraditional -Wcast-align \
-         -Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-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
+	-malign-functions=2 #$(WARNMORE) -g -DPNG_DEBUG=5
 LDFLAGS=-L. -L$(ZLIBLIB) -lpng -lzdll -Zcrtdll
 AR=emxomfar
 
@@ -23,8 +23,8 @@ 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
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
 
 .SUFFIXES:      .c .o
 

scripts/makefile.sco

@@ -25,15 +25,15 @@ RANLIB=echo
 # read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
 # have to change it.
 PNGMAJ = 2
-PNGMIN = 1.0.2a
+PNGMIN = 1.0.5d
 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
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -49,10 +49,10 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 libpng.so: libpng.so.$(PNGMAJ)
-	ln -s -f libpng.so.$(PNGMAJ) libpng.so
+	ln -f -s libpng.so.$(PNGMAJ) libpng.so
 
 libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
-	ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+	ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
 
 libpng.so.$(PNGVER): $(OBJSDLL)
 	$(CC) -G  -Wl,-h,libpng.so.$(PNGMAJ) -o libpng.so.$(PNGVER) \
@@ -71,8 +71,8 @@ install: libpng.a libpng.so.$(PNGVER)
 	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
 	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
 	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
-	(cd $(LIBPATH); ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
-	 ln -s -f libpng.so.$(PNGMAJ) 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

scripts/makefile.sgi

@@ -14,6 +14,7 @@ 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
 

scripts/makefile.solaris

@@ -1,12 +1,18 @@
 # makefile for libpng on Solaris 2.x with gcc
-# Contributed by William L. Sebok, based on makefile.lnx
+# Contributed by William L. Sebok, based on makefile.linux
 # 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
 
-# where make install puts libpng.a, libpng.so*, and png.h
+# 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 to put
+# /usr/ccs/bin ahead of /usr/ucb.  The environment variable LD_LIBRARY_PATH
+# should not be set at all.  If it is, things are likely to break because
+# of the libucb dependency that is created.
+
+# Where make install puts libpng.a, libpng.so*, and png.h
 prefix=/usr/local
 
 # Where the zlib library and include files are located
@@ -19,10 +25,10 @@ ZLIBLIB=/usr/local/lib
 ZLIBINC=/usr/local/include
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow \
-         -Wmissing-declarations -Wtraditional -Wcast-align \
-         -Wstrict-prototypes -Wmissing-prototypes #-Wconversion
+	-Wmissing-declarations -Wtraditional -Wcast-align \
+	-Wstrict-prototypes -Wmissing-prototypes #-Wconversion
 CFLAGS=-I$(ZLIBINC) -Wall -O3 \
-      # $(WARNMORE) -g -DPNG_DEBUG=5
+	# $(WARNMORE) -g -DPNG_DEBUG=5
 LDFLAGS=-L. -R. -L$(ZLIBLIB) -R$(ZLIBLIB) -lpng -lz -lm
 
 #RANLIB=ranlib
@@ -31,15 +37,15 @@ RANLIB=echo
 # read libpng.txt or png.h to see why PNGMAJ is 2.  You should not
 # have to change it.
 PNGMAJ = 2
-PNGMIN = 1.0.2a
+PNGMIN = 1.0.5d
 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
+	pngread.o pngrio.o pngwio.o pngwrite.o pngrtran.o \
+	pngwtran.o pngmem.o pngerror.o pngpread.o
 
 OBJSDLL = $(OBJS:.o=.pic.o)
 
@@ -55,10 +61,10 @@ libpng.a: $(OBJS)
 	$(RANLIB) $@
 
 libpng.so: libpng.so.$(PNGMAJ)
-	ln -s -f libpng.so.$(PNGMAJ) libpng.so
+	ln -f -s libpng.so.$(PNGMAJ) libpng.so
 
 libpng.so.$(PNGMAJ): libpng.so.$(PNGVER)
-	ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
+	ln -f -s libpng.so.$(PNGVER) libpng.so.$(PNGMAJ)
 
 libpng.so.$(PNGVER): $(OBJSDLL)
 	$(LD) -G -L$(ZLIBLIB) -R$(ZLIBLIB) -h libpng.so.$(PNGMAJ) \
@@ -77,8 +83,8 @@ install: libpng.a libpng.so.$(PNGVER)
 	cp libpng.a libpng.so.$(PNGVER) $(LIBPATH)
 	chmod 755 $(LIBPATH)/libpng.so.$(PNGVER)
 	-@/bin/rm -f $(LIBPATH)/libpng.so.$(PNGMAJ) $(LIBPATH)/libpng.so
-	(cd $(LIBPATH); ln -s -f libpng.so.$(PNGVER) libpng.so.$(PNGMAJ); \
-	 ln -s -f libpng.so.$(PNGMAJ) 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

scripts/makefile.sunos

@@ -13,8 +13,8 @@ ZLIBINC=../zlib
 
 
 WARNMORE=-Wwrite-strings -Wpointer-arith -Wshadow -Wconversion \
-         -Wmissing-declarations -Wtraditional -Wcast-align \
-         -Wstrict-prototypes -Wmissing-prototypes
+	-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

scripts/makefile.turboc3

@@ -1,7 +1,7 @@
 # Makefile for libpng
 # TurboC++ 3.0 (Note: All modules are compiled in C mode)
 
-# To use, do "make -fmakefile.tc3"
+# To use, do "make -fmakefile.turboc3"
 
 # ------------- Turbo C++ 3.0 -------------
 MODEL=-ml
@@ -45,38 +45,38 @@ pngrutil$(O): png.h pngconf.h
 		  $(CC) -c $(CFLAGS) $*.c
 
 pngerror$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngmem$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngrio$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngwio$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngtest$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngtrans$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngwrite$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngwtran$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 pngwutil$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c
+	$(CC) -c $(CFLAGS) $*.c
 
 libpng.lib: $(OBJS1) $(OBJS2) $(OBJS3)
-        $(LIB) libpng +$(OBJSL1)
-        $(LIB) libpng +$(OBJSL2)
-        $(LIB) libpng +$(OBJSL3)
+	$(LIB) libpng +$(OBJSL1)
+	$(LIB) libpng +$(OBJSL2)
+	$(LIB) libpng +$(OBJSL3)
 
 pngtest$(E): pngtest$(O) libpng.lib
-        $(CC) $(LDFLAGS) pngtest.obj libpng.lib zlib.lib
+	$(CC) $(LDFLAGS) pngtest.obj libpng.lib zlib.lib
 
 # End of makefile for libpng

scripts/makefile.vcawin32

@@ -0,0 +1,94 @@
+# 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.vcawin32"
+
+# ---------- Microsoft Visual C++ 5.0 and later, uses assembler code------
+
+# Caution: the assembler code was introduced at libpng version 1.0.4 and has
+# not yet been thoroughly tested.
+
+# If you don't want to use assembler code, use makefile.vcwin32 instead.
+
+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/makefile.vcwin32

@@ -2,11 +2,13 @@
 # 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"
+# To use, do "nmake /f scripts\makefile.vcwin32"
+
+# ---------- Microsoft Visual C++ 4.0 and later, no assembler code------
+# If you want to use assembler code, use makefile.vcawin32 instead.
 
-# ------------- Microsoft Visual C++ 4.0 and later -------------
 MODEL=- 
-CFLAGS=-Ox -GA3s -nologo -W3 -I..\zlib
+CFLAGS= -Ox -GA3s -nologo -W3 -I..\zlib
 
 CC=cl
 LD=link
@@ -27,52 +29,52 @@ png$(O): png.h pngconf.h
 		  $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngset$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(CC) -c $(CFLAGS) $*.c $(ERRFILE)
 
 pngget$(O): png.h pngconf.h
-        $(CC) -c $(CFLAGS) $*.c $(ERRFILE)
+	$(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)
+	$(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 $(ERRFILE)
+pngrutil$(O): png.h pngconf.h pngasmrd.h
+	$(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) $(OBJS3)
-        del libpng.lib
+	del libpng.lib
 	lib /OUT:libpng.lib $(OBJS1) $(OBJS2) $(OBJS3)
 
 pngtest.exe: pngtest.obj libpng.lib