Add missing WXK constants for the control keys

[wxWidgets.git] / src / png / pngconf.h

diff --git a/src/png/pngconf.h b/src/png/pngconf.h
index 028f2a1a70cbfa642e1caa47b46ca2c48cfcb79f..f6441d201e35dc9879a5b013f9e1540a97c9cdb7 100644 (file)
--- a/src/png/pngconf.h
+++ b/src/png/pngconf.h
@@ -1,11 +1,16 @@
 
 /* pngconf.h - machine configurable file for libpng
  *
 
 /* pngconf.h - machine configurable file for libpng
  *

- * libpng 1.0.3 - January 14, 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
+ * libpng version 1.5.7 - December 15, 2011
+ *
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *

  */
 
 /* Any machine specific code is near the front of this file, so if you
  */
 
 /* Any machine specific code is near the front of this file, so if you


@@ -17,64 +22,61 @@
 #ifndef PNGCONF_H
 #define PNGCONF_H
 
 #ifndef PNGCONF_H
 #define PNGCONF_H
 

-
-/* This is the size of the compression buffer, and thus the size of
- * an IDAT chunk.  Make this whatever size you feel is best for your
- * machine.  One of these will be allocated per png_struct.  When this
- * is full, it writes the data to the disk, and does some other
- * calculations.  Making this an extremely small size will slow
- * the library down, but you may want to experiment to determine
- * where it becomes significant, if you are concerned with memory
- * usage.  Note that zlib allocates at least 32Kb also.  For readers,
- * this describes the size of the buffer available to read the data in.
- * Unless this gets smaller than the size of a row (compressed),
- * it should not make much difference how big this is.
- */
-
-#ifndef PNG_ZBUF_SIZE
-#define PNG_ZBUF_SIZE 8192
+#ifdef __DMC__
+#define PNG_NO_SNPRINTF

 #endif
 
 #endif
 

-/* If you are running on a machine where you cannot allocate more
- * than 64K of memory at once, uncomment this.  While libpng will not
- * normally need that much memory in a chunk (unless you load up a very
- * large file), zlib needs to know how big of a chunk it can use, and
- * libpng thus makes sure to check any memory allocation to verify it
- * will fit into memory.
-#define PNG_MAX_MALLOC_64K
+#ifndef PNG_BUILDING_SYMBOL_TABLE
+/* PNG_NO_LIMITS_H may be used to turn off the use of the standard C
+ * definition file for  machine specific limits, this may impact the
+ * correctness of the definitons below (see uses of INT_MAX).

  */
  */

-#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
-#define PNG_MAX_MALLOC_64K
-#endif
+#  ifndef PNG_NO_LIMITS_H
+#    include <limits.h>
+#  endif

 
 

-/* This protects us against compilers that run on a windowing system
- * and thus don't have or would rather us not use the stdio types:
- * stdin, stdout, and stderr.  The only one currently used is stderr
- * in png_error() and png_warning().  #defining PNG_NO_CONSOLE_IO will
- * prevent these from being compiled and used. #defining PNG_NO_STDIO
- * will also prevent these, plus will prevent the entire set of stdio
- * macros and functions (FILE *, printf, etc.) from being compiled and used,
- * unless PNG_DEBUG has been #defined.
- *
- * #define PNG_NO_CONSOLE_IO
- * #define PNG_NO_STDIO
+/* For the memory copy APIs (i.e. the standard definitions of these),
+ * because this file defines png_memcpy and so on the base APIs must
+ * be defined here.

  */
  */

+#  ifdef BSD
+#    include <strings.h>
+#  else
+#    include <string.h>
+#  endif

 
 

-#ifdef PNG_DEBUG
-#  if (PNG_DEBUG > 0)
+/* For png_FILE_p - this provides the standard definition of a
+ * FILE
+ */
+#  ifdef PNG_STDIO_SUPPORTED

 #    include <stdio.h>
 #  endif
 #    include <stdio.h>
 #  endif

-#else
-#  ifdef PNG_NO_STDIO
-#    ifndef PNG_NO_CONSOLE_IO
-#      define PNG_NO_CONSOLE_IO
-#    endif
-#  else
-#    include <stdio.h>
+#endif
+
+/* This controls optimization of the reading of 16 and 32 bit values
+ * from PNG files.  It can be set on a per-app-file basis - it
+ * just changes whether a macro is used to the function is called.
+ * The library builder sets the default, if read functions are not
+ * built into the library the macro implementation is forced on.
+ */
+#ifndef PNG_READ_INT_FUNCTIONS_SUPPORTED
+#  define PNG_USE_READ_MACROS
+#endif
+#if !defined(PNG_NO_USE_READ_MACROS) && !defined(PNG_USE_READ_MACROS)
+#  if PNG_DEFAULT_READ_MACROS
+#    define PNG_USE_READ_MACROS

 #  endif
 #endif
 
 #  endif
 #endif
 

-/* This macro protects us against machines that don't have function
+/* COMPILER SPECIFIC OPTIONS.
+ *
+ * These options are provided so that a variety of difficult compilers
+ * can be used.  Some are fixed at build time (e.g. PNG_API_RULE
+ * below) but still have compiler specific implementations, others
+ * may be changed on a per-file basis when compiling against libpng.
+ */
+
+/* The PNGARG macro protects us against machines that don't have function

  * prototypes (ie K&R style headers).  If your compiler does not handle
  * function prototypes, define this macro and use the included ansi2knr.
  * I've always been able to use _NO_PROTO as the indicator, but you may
  * prototypes (ie K&R style headers).  If your compiler does not handle
  * function prototypes, define this macro and use the included ansi2knr.
  * I've always been able to use _NO_PROTO as the indicator, but you may


@@ -83,456 +85,352 @@
  */
 #ifndef PNGARG
 
  */
 #ifndef PNGARG
 

-#ifdef OF /* zlib prototype munger */
-#define PNGARG(arglist) OF(arglist)
-#else
+#  ifdef OF /* zlib prototype munger */
+#    define PNGARG(arglist) OF(arglist)
+#  else

 
 

-#ifdef _NO_PROTO
-#define PNGARG(arglist) ()
-#else
-#define PNGARG(arglist) arglist
-#endif /* _NO_PROTO */
+#    ifdef _NO_PROTO
+#      define PNGARG(arglist) ()
+#    else
+#      define PNGARG(arglist) arglist
+#    endif /* _NO_PROTO */

 
 

-#endif /* OF */
+#  endif /* OF */

 
 #endif /* PNGARG */
 
 
 #endif /* PNGARG */
 

-/* Try to determine if we are compiling on a Mac.  Note that testing for
- * just __MWERKS__ is not good enough, because the Codewarrior is now used
- * on non-Mac platforms.
- */
-#ifndef MACOS
-#if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
-    defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
-#define MACOS
-#endif
-#endif
-
-/* enough people need this for various reasons to include it here */
-#if !defined(MACOS) && !defined(RISCOS)
-#include <sys/types.h>
-#endif
-
-/* This is an attempt to force a single setjmp behaviour on Linux.  If
- * the X config stuff didn't define _BSD_SOURCE we wouldn't need this.
+/* Function calling conventions.
+ * =============================
+ * Normally it is not necessary to specify to the compiler how to call
+ * a function - it just does it - however on x86 systems derived from
+ * Microsoft and Borland C compilers ('IBM PC', 'DOS', 'Windows' systems
+ * and some others) there are multiple ways to call a function and the
+ * default can be changed on the compiler command line.  For this reason
+ * libpng specifies the calling convention of every exported function and
+ * every function called via a user supplied function pointer.  This is
+ * done in this file by defining the following macros:
+ *
+ * PNGAPI    Calling convention for exported functions.
+ * PNGCBAPI  Calling convention for user provided (callback) functions.
+ * PNGCAPI   Calling convention used by the ANSI-C library (required
+ *           for longjmp callbacks and sometimes used internally to
+ *           specify the calling convention for zlib).
+ *
+ * These macros should never be overridden.  If it is necessary to
+ * change calling convention in a private build this can be done
+ * by setting PNG_API_RULE (which defaults to 0) to one of the values
+ * below to select the correct 'API' variants.
+ *
+ * PNG_API_RULE=0 Use PNGCAPI - the 'C' calling convention - throughout.
+ *                This is correct in every known environment.
+ * PNG_API_RULE=1 Use the operating system convention for PNGAPI and
+ *                the 'C' calling convention (from PNGCAPI) for
+ *                callbacks (PNGCBAPI).  This is no longer required
+ *                in any known environment - if it has to be used
+ *                please post an explanation of the problem to the
+ *                libpng mailing list.
+ *
+ * These cases only differ if the operating system does not use the C
+ * calling convention, at present this just means the above cases
+ * (x86 DOS/Windows sytems) and, even then, this does not apply to
+ * Cygwin running on those systems.
+ *
+ * Note that the value must be defined in pnglibconf.h so that what
+ * the application uses to call the library matches the conventions
+ * set when building the library.

  */
  */

-#ifdef __linux__
-#ifdef _BSD_SOURCE
-#define _PNG_SAVE_BSD_SOURCE
-#undef _BSD_SOURCE
-#endif
-#ifdef _SETJMP_H
-__png.h__ already includes setjmp.h
-__dont__ include it again
-#endif
-#endif /* __linux__ */

 
 

-/* include setjmp.h for error handling */
-#include <setjmp.h>
-
-#ifdef __linux__
-#ifdef _PNG_SAVE_BSD_SOURCE
-#define _BSD_SOURCE
-#undef _PNG_SAVE_BSD_SOURCE
-#endif
-#endif /* __linux__ */
-
-#ifdef BSD
-#include <strings.h>
-#else
-#include <string.h>
-#endif
-
-/* Other defines for things like memory and the like can go here.  */
-#ifdef PNG_INTERNAL
-#include <stdlib.h>
-
-/* The functions exported by PNG_EXTERN are PNG_INTERNAL functions, which
- * aren't usually used outside the library (as far as I know), so it is
- * debatable if they should be exported at all.  In the future, when it is
- * possible to have run-time registry of chunk-handling functions, some of
- * these will be made available again.
-#define PNG_EXTERN extern
+/* Symbol export
+ * =============
+ * When building a shared library it is almost always necessary to tell
+ * the compiler which symbols to export.  The png.h macro 'PNG_EXPORT'
+ * is used to mark the symbols.  On some systems these symbols can be
+ * extracted at link time and need no special processing by the compiler,
+ * on other systems the symbols are flagged by the compiler and just
+ * the declaration requires a special tag applied (unfortunately) in a
+ * compiler dependent way.  Some systems can do either.
+ *
+ * A small number of older systems also require a symbol from a DLL to
+ * be flagged to the program that calls it.  This is a problem because
+ * we do not know in the header file included by application code that
+ * the symbol will come from a shared library, as opposed to a statically
+ * linked one.  For this reason the application must tell us by setting
+ * the magic flag PNG_USE_DLL to turn on the special processing before
+ * it includes png.h.
+ *
+ * Four additional macros are used to make this happen:
+ *
+ * PNG_IMPEXP The magic (if any) to cause a symbol to be exported from
+ *            the build or imported if PNG_USE_DLL is set - compiler
+ *            and system specific.
+ *
+ * PNG_EXPORT_TYPE(type) A macro that pre or appends PNG_IMPEXP to
+ *                       'type', compiler specific.
+ *
+ * PNG_DLL_EXPORT Set to the magic to use during a libpng build to
+ *                make a symbol exported from the DLL.  Not used in the
+ *                public header files; see pngpriv.h for how it is used
+ *                in the libpng build.
+ *
+ * PNG_DLL_IMPORT Set to the magic to force the libpng symbols to come
+ *                from a DLL - used to define PNG_IMPEXP when
+ *                PNG_USE_DLL is set.

  */
  */

-#define PNG_EXTERN

 
 

-/* Other defines specific to compilers can go here.  Try to keep
- * them inside an appropriate ifdef/endif pair for portability.
+/* System specific discovery.
+ * ==========================
+ * This code is used at build time to find PNG_IMPEXP, the API settings
+ * and PNG_EXPORT_TYPE(), it may also set a macro to indicate the DLL
+ * import processing is possible.  On Windows/x86 systems it also sets
+ * compiler-specific macros to the values required to change the calling
+ * conventions of the various functions.

  */
  */

+#if ( defined(_Windows) || defined(_WINDOWS) || defined(WIN32) ||\
+      defined(_WIN32) || defined(__WIN32__) || defined(__CYGWIN__) ) &&\
+    ( defined(_X86_) || defined(_X64_) || defined(_M_IX86) ||\
+      defined(_M_X64) || defined(_M_IA64) )
+  /* Windows system (DOS doesn't support DLLs) running on x86/x64.  Includes
+   * builds under Cygwin or MinGW.  Also includes Watcom builds but these need
+   * special treatment because they are not compatible with GCC or Visual C
+   * because of different calling conventions.
+   */
+#  if PNG_API_RULE == 2
+    /* If this line results in an error, either because __watcall is not
+     * understood or because of a redefine just below you cannot use *this*
+     * build of the library with the compiler you are using.  *This* build was
+     * build using Watcom and applications must also be built using Watcom!
+     */
+#    define PNGCAPI __watcall
+#  endif

 
 

-#if defined(MACOS)
-/* We need to check that <math.h> hasn't already been included earlier
- * as it seems it doesn't agree with <fp.h>, yet we should really use
- * <fp.h> if possible.
- */
-#if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
-#include <fp.h>
-#endif
-#else
-#include <math.h>
-#endif
+#  if defined(__GNUC__) || (defined (_MSC_VER) && (_MSC_VER >= 800))
+#    define PNGCAPI __cdecl
+#    if PNG_API_RULE == 1
+#      define PNGAPI __stdcall
+#    endif
+#  else
+    /* An older compiler, or one not detected (erroneously) above,
+     * if necessary override on the command line to get the correct
+     * variants for the compiler.
+     */
+#    ifndef PNGCAPI
+#      define PNGCAPI _cdecl
+#    endif
+#    if PNG_API_RULE == 1 && !defined(PNGAPI)
+#      define PNGAPI _stdcall
+#    endif
+#  endif /* compiler/api */
+  /* NOTE: PNGCBAPI always defaults to PNGCAPI. */

 
 

-/* Codewarrior on NT has linking problems without this. */
-#if defined(__MWERKS__) && defined(WIN32)
-#define PNG_ALWAYS_EXTERN
-#endif
+#  if defined(PNGAPI) && !defined(PNG_USER_PRIVATEBUILD)
+   ERROR: PNG_USER_PRIVATEBUILD must be defined if PNGAPI is changed
+#  endif

 
 

-/* For some reason, Borland C++ defines memcmp, etc. in mem.h, not
- * stdlib.h like it should (I think).  Or perhaps this is a C++
- * "feature"?
- */
-#ifdef __TURBOC__
-#include <mem.h>
-#include "alloc.h"
-#endif
+#  if (defined(_MSC_VER) && _MSC_VER < 800) ||\
+      (defined(__BORLANDC__) && __BORLANDC__ < 0x500)
+    /* older Borland and MSC
+     * compilers used '__export' and required this to be after
+     * the type.
+     */
+#    ifndef PNG_EXPORT_TYPE
+#      define PNG_EXPORT_TYPE(type) type PNG_IMPEXP
+#    endif
+#    define PNG_DLL_EXPORT __export
+#  else /* newer compiler */
+#    define PNG_DLL_EXPORT __declspec(dllexport)
+#    ifndef PNG_DLL_IMPORT
+#      define PNG_DLL_IMPORT __declspec(dllimport)
+#    endif
+#  endif /* compiler */

 
 

-#ifdef _MSC_VER
-#include <malloc.h>
-#endif
+#else /* !Windows/x86 */
+#  if (defined(__IBMC__) || defined(__IBMCPP__)) && defined(__OS2__)
+#    define PNGAPI _System
+#  else /* !Windows/x86 && !OS/2 */
+    /* Use the defaults, or define PNG*API on the command line (but
+     * this will have to be done for every compile!)
+     */
+#  endif /* other system, !OS/2 */
+#endif /* !Windows/x86 */

 
 

-/* This controls how fine the dithering gets.  As this allocates
- * a largish chunk of memory (32K), those who are not as concerned
- * with dithering quality can decrease some or all of these.
- */
-#ifndef PNG_DITHER_RED_BITS
-#define PNG_DITHER_RED_BITS 5
-#endif
-#ifndef PNG_DITHER_GREEN_BITS
-#define PNG_DITHER_GREEN_BITS 5
+/* Now do all the defaulting . */
+#ifndef PNGCAPI
+#  define PNGCAPI

 #endif
 #endif

-#ifndef PNG_DITHER_BLUE_BITS
-#define PNG_DITHER_BLUE_BITS 5
+#ifndef PNGCBAPI
+#  define PNGCBAPI PNGCAPI

 #endif
 #endif

-
-/* This controls how fine the gamma correction becomes when you
- * are only interested in 8 bits anyway.  Increasing this value
- * results in more memory being used, and more pow() functions
- * being called to fill in the gamma tables.  Don't set this value
- * less then 8, and even that may not work (I haven't tested it).
- */
-
-#ifndef PNG_MAX_GAMMA_8
-#define PNG_MAX_GAMMA_8 11
-#endif
-
-/* This controls how much a difference in gamma we can tolerate before
- * we actually start doing gamma conversion.
- */
-#ifndef PNG_GAMMA_THRESHOLD
-#define PNG_GAMMA_THRESHOLD 0.05
+#ifndef PNGAPI
+#  define PNGAPI PNGCAPI

 #endif
 
 #endif
 

-#endif /* PNG_INTERNAL */
-
-/* The following uses const char * instead of char * for error
- * and warning message functions, so some compilers won't complain.
- * If you do not want to use const, define PNG_NO_CONST here.
+/* PNG_IMPEXP may be set on the compilation system command line or (if not set)
+ * then in an internal header file when building the library, otherwise (when
+ * using the library) it is set here.

  */
  */

+#ifndef PNG_IMPEXP
+#  if defined(PNG_USE_DLL) && defined(PNG_DLL_IMPORT)
+     /* This forces use of a DLL, disallowing static linking */
+#    define PNG_IMPEXP PNG_DLL_IMPORT
+#  endif

 
 

-#ifndef PNG_NO_CONST
-#  define PNG_CONST const
-#else
-#  define PNG_CONST
+#  ifndef PNG_IMPEXP
+#    define PNG_IMPEXP
+#  endif

 #endif
 
 #endif
 

-/* The following defines give you the ability to remove code from the
- * library that you will not be using.  I wish I could figure out how to
- * automate this, but I can't do that without making it seriously hard
- * on the users.  So if you are not using an ability, change the #define
- * to and #undef, and that part of the library will not be compiled.  If
- * your linker can't find a function, you may want to make sure the
- * ability is defined here.  Some of these depend upon some others being
- * defined.  I haven't figured out all the interactions here, so you may
- * have to experiment awhile to get everything to compile.  If you are
- * creating or using a shared library, you probably shouldn't touch this,
- * as it will affect the size of the structures, and this will cause bad
- * things to happen if the library and/or application ever change.
+/* In 1.5.2 the definition of PNG_FUNCTION has been changed to always treat
+ * 'attributes' as a storage class - the attributes go at the start of the
+ * function definition, and attributes are always appended regardless of the
+ * compiler.  This considerably simplifies these macros but may cause problems
+ * if any compilers both need function attributes and fail to handle them as
+ * a storage class (this is unlikely.)

  */
  */

-
-/* Any transformations you will not be using can be undef'ed here */
-
-/* GR-P, 0.96a: Set "*TRANSFORMS_SUPPORTED as default but allow user
-   to turn it off with "*TRANSFORMS_NOT_SUPPORTED" or *PNG_NO_*_TRANSFORMS
-   on the compile line, then pick and choose which ones to define without
-   having to edit this file. It is safe to use the *TRANSFORMS_NOT_SUPPORTED
-   if you only want to have a png-compliant reader/writer but don't need
-   any of the extra transformations.  This saves about 80 kbytes in a
-   typical installation of the library. (PNG_NO_* form added in version
-   1.0.1c, for consistency)
- */
-
-
-#if !defined(PNG_READ_TRANSFORMS_NOT_SUPPORTED) && \
-    !defined(PNG_NO_READ_TRANSFORMS)
-#define PNG_READ_TRANSFORMS_SUPPORTED
-#endif
-#if !defined(PNG_WRITE_TRANSFORMS_NOT_SUPPORTED) && \
-    !defined(PNG_NO_WRITE_TRANSFORMS)
-#define PNG_WRITE_TRANSFORMS_SUPPORTED
+#ifndef PNG_FUNCTION
+#  define PNG_FUNCTION(type, name, args, attributes) attributes type name args

 #endif
 
 #endif
 

-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-#ifndef PNG_NO_READ_EXPAND
-#define PNG_READ_EXPAND_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_SHIFT
-#define PNG_READ_SHIFT_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_PACK
-#define PNG_READ_PACK_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_BGR
-#define PNG_READ_BGR_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_SWAP
-#define PNG_READ_SWAP_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_PACKSWAP
-#define PNG_READ_PACKSWAP_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_INVERT
-#define PNG_READ_INVERT_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_DITHER
-#define PNG_READ_DITHER_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_BACKGROUND
-#define PNG_READ_BACKGROUND_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_16_TO_8
-#define PNG_READ_16_TO_8_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_FILLER
-#define PNG_READ_FILLER_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_GAMMA
-#define PNG_READ_GAMMA_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_GRAY_TO_RGB
-#define PNG_READ_GRAY_TO_RGB_SUPPORTED
+#ifndef PNG_EXPORT_TYPE
+#  define PNG_EXPORT_TYPE(type) PNG_IMPEXP type

 #endif
 #endif

-#ifndef PNG_NO_READ_SWAP_ALPHA
-#define PNG_READ_SWAP_ALPHA_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_INVERT_ALPHA
-#define PNG_READ_INVERT_ALPHA_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_STRIP_ALPHA
-#define PNG_READ_STRIP_ALPHA_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_USER_TRANSFORM
-#define PNG_READ_USER_TRANSFORM_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_RGB_TO_GRAY
-#define PNG_READ_RGB_TO_GRAY_SUPPORTED
-#endif
-#endif /* PNG_READ_TRANSFORMS_SUPPORTED */
-
-#if !defined(PNG_NO_PROGRESSIVE_READ) && \
- !defined(PNG_PROGRESSIVE_READ_NOT_SUPPORTED) /* if you don't do progressive   */
-#define PNG_PROGRESSIVE_READ_SUPPORTED       /* reading.  This is not talking */
-#endif                               /* about interlacing capability!  You'll */
-              /* still have interlacing unless you change the following line: */
-#define PNG_READ_INTERLACING_SUPPORTED /* required for PNG-compliant decoders */

 
 

-#ifndef PNG_NO_READ_COMPOSITED_NODIV
-#define PNG_READ_COMPOSITE_NODIV_SUPPORTED    /* well tested on Intel and SGI */
-#endif
+   /* The ordinal value is only relevant when preprocessing png.h for symbol
+    * table entries, so we discard it here.  See the .dfn files in the
+    * scripts directory.
+    */
+#ifndef PNG_EXPORTA

 
 

-#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
-#ifndef PNG_NO_WRITE_SHIFT
-#define PNG_WRITE_SHIFT_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_PACK
-#define PNG_WRITE_PACK_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_BGR
-#define PNG_WRITE_BGR_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_SWAP
-#define PNG_WRITE_SWAP_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_PACKSWAP
-#define PNG_WRITE_PACKSWAP_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_INVERT
-#define PNG_WRITE_INVERT_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_FILLER
-#define PNG_WRITE_FILLER_SUPPORTED  /* This is the same as WRITE_STRIP_ALPHA */
+#  define PNG_EXPORTA(ordinal, type, name, args, attributes)\
+      PNG_FUNCTION(PNG_EXPORT_TYPE(type),(PNGAPI name),PNGARG(args), \
+        extern attributes)

 #endif
 #endif

-#ifndef PNG_NO_WRITE_SWAP_ALPHA
-#define PNG_WRITE_SWAP_ALPHA_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_INVERT_ALPHA
-#define PNG_WRITE_INVERT_ALPHA_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_USER_TRANSFORM
-#define PNG_WRITE_USER_TRANSFORM_SUPPORTED
-#endif
-#endif /* PNG_WRITE_TRANSFORMS_SUPPORTED */

 
 

-#define PNG_WRITE_INTERLACING_SUPPORTED  /* not required for PNG-compliant
-                                            encoders, but can cause trouble
-                                            if left undefined */
+/* ANSI-C (C90) does not permit a macro to be invoked with an empty argument,
+ * so make something non-empty to satisfy the requirement:
+ */
+#define PNG_EMPTY /*empty list*/

 
 

-#ifndef PNG_NO_WRITE_WEIGHTED_FILTER
-#define PNG_WRITE_WEIGHTED_FILTER_SUPPORTED
-#endif
+#define PNG_EXPORT(ordinal, type, name, args)\
+   PNG_EXPORTA(ordinal, type, name, args, PNG_EMPTY)

 
 

-#ifndef PNG_NO_WRITE_FLUSH
-#define PNG_WRITE_FLUSH_SUPPORTED
+/* Use PNG_REMOVED to comment out a removed interface. */
+#ifndef PNG_REMOVED
+#  define PNG_REMOVED(ordinal, type, name, args, attributes)

 #endif
 
 #endif
 

-#ifndef PNG_NO_STDIO
-#define PNG_TIME_RFC1123_SUPPORTED
+#ifndef PNG_CALLBACK
+#  define PNG_CALLBACK(type, name, args) type (PNGCBAPI name) PNGARG(args)

 #endif
 
 #endif
 

-/* This adds extra functions in pngget.c for accessing data from the
- * info pointer (added in version 0.99)
- * png_get_image_width()
- * png_get_image_height()
- * png_get_bit_depth()
- * png_get_color_type()
- * png_get_compression_type()
- * png_get_filter_type()
- * png_get_interlace_type()
- * png_get_pixel_aspect_ratio()
- * png_get_pixels_per_meter()
- * png_get_x_offset_pixels()
- * png_get_y_offset_pixels()
- * png_get_x_offset_microns()
- * png_get_y_offset_microns()
+/* Support for compiler specific function attributes.  These are used
+ * so that where compiler support is available incorrect use of API
+ * functions in png.h will generate compiler warnings.
+ *
+ * Added at libpng-1.2.41.

  */
  */

-#ifndef PNG_NO_EASY_ACCESS
-#define PNG_EASY_ACCESS_SUPPORTED
+
+#ifndef PNG_NO_PEDANTIC_WARNINGS
+#  ifndef PNG_PEDANTIC_WARNINGS_SUPPORTED
+#    define PNG_PEDANTIC_WARNINGS_SUPPORTED
+#  endif

 #endif
 
 #endif
 

-/* These are currently experimental features, define them if you want */
-
-/* very little testing */
-/*
-#define PNG_READ_16_TO_8_ACCURATE_SCALE_SUPPORTED
-#define PNG_USER_MEM_SUPPORTED
-*/
-
-/* This is only for PowerPC big-endian and 680x0 systems */
-/* some testing */
-/*
-#define PNG_READ_BIG_ENDIAN_SUPPORTED
-*/
-
-/* These functions are turned off by default, as they will be phased out. */
-/*
-#define  PNG_USELESS_TESTS_SUPPORTED
-#define  PNG_CORRECT_PALETTE_SUPPORTED
-*/
-
-/* Any chunks you are not interested in, you can undef here.  The
- * ones that allocate memory may be expecially important (hIST,
- * tEXt, zTXt, tRNS, pCAL).  Others will just save time and make png_info
- * a bit smaller.
- */
+#ifdef PNG_PEDANTIC_WARNINGS_SUPPORTED
+  /* Support for compiler specific function attributes.  These are used
+   * so that where compiler support is available incorrect use of API
+   * functions in png.h will generate compiler warnings.  Added at libpng
+   * version 1.2.41.
+   */
+#  if defined(__GNUC__)
+#    ifndef PNG_USE_RESULT
+#      define PNG_USE_RESULT __attribute__((__warn_unused_result__))
+#    endif
+#    ifndef PNG_NORETURN
+#      define PNG_NORETURN   __attribute__((__noreturn__))
+#    endif
+#    ifndef PNG_ALLOCATED
+#      define PNG_ALLOCATED  __attribute__((__malloc__))
+#    endif
+#    ifndef PNG_DEPRECATED
+#      define PNG_DEPRECATED __attribute__((__deprecated__))
+#    endif
+#    ifndef PNG_PRIVATE
+#      if 0 /* Doesn't work so we use deprecated instead*/
+#        define PNG_PRIVATE \
+          __attribute__((warning("This function is not exported by libpng.")))
+#      else
+#        define PNG_PRIVATE \
+          __attribute__((__deprecated__))
+#      endif
+#    endif
+#  endif /* __GNUC__ */

 
 

-#if !defined(PNG_READ_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
-    !defined(PNG_NO_READ_ANCILLARY_CHUNKS)
-#define PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
-#endif
-#if !defined(PNG_WRITE_ANCILLARY_CHUNKS_NOT_SUPPORTED) && \
-    !defined(PNG_NO_WRITE_ANCILLARY_CHUNKS)
-#define PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
-#endif
+#  if defined(_MSC_VER)  && (_MSC_VER >= 1300)
+#    ifndef PNG_USE_RESULT
+#      define PNG_USE_RESULT /* not supported */
+#    endif
+#    ifndef PNG_NORETURN
+#      define PNG_NORETURN __declspec(noreturn)
+#    endif
+#    ifndef PNG_ALLOCATED
+#      if (_MSC_VER >= 1400)
+#        define PNG_ALLOCATED __declspec(restrict)
+#      endif
+#    endif
+#    ifndef PNG_DEPRECATED
+#      define PNG_DEPRECATED __declspec(deprecated)
+#    endif
+#    ifndef PNG_PRIVATE
+#      define PNG_PRIVATE __declspec(deprecated)
+#    endif
+#  endif /* _MSC_VER */
+#endif /* PNG_PEDANTIC_WARNINGS */

 
 

-#ifdef PNG_READ_ANCILLARY_CHUNKS_SUPPORTED
-#ifndef PNG_NO_READ_bKGD
-#define PNG_READ_bKGD_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_cHRM
-#define PNG_READ_cHRM_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_gAMA
-#define PNG_READ_gAMA_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_hIST
-#define PNG_READ_hIST_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_oFFs
-#define PNG_READ_oFFs_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_pCAL
-#define PNG_READ_pCAL_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_pHYs
-#define PNG_READ_pHYs_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_sBIT
-#define PNG_READ_sBIT_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_sRGB
-#define PNG_READ_sRGB_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_tEXt
-#define PNG_READ_tEXt_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_tIME
-#define PNG_READ_tIME_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_tRNS
-#define PNG_READ_tRNS_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_zTXt
-#define PNG_READ_zTXt_SUPPORTED
-#endif
-#ifndef PNG_NO_READ_OPT_PLTE
-#define PNG_READ_OPT_PLTE_SUPPORTED /* only affects support of the optional */
-#endif                              /* PLTE chunk in RGB and RGBA images */
-#endif /* PNG_READ_ANCILLARY_CHUNKS_SUPPORTED */
-
-#ifdef PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED
-#ifndef PNG_NO_WRITE_bKGD
-#define PNG_WRITE_bKGD_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_cHRM
-#define PNG_WRITE_cHRM_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_gAMA
-#define PNG_WRITE_gAMA_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_hIST
-#define PNG_WRITE_hIST_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_oFFs
-#define PNG_WRITE_oFFs_SUPPORTED
+#ifndef PNG_DEPRECATED
+#  define PNG_DEPRECATED  /* Use of this function is deprecated */

 #endif
 #endif

-#ifndef PNG_NO_WRITE_pCAL
-#define PNG_WRITE_pCAL_SUPPORTED
+#ifndef PNG_USE_RESULT
+#  define PNG_USE_RESULT  /* The result of this function must be checked */

 #endif
 #endif

-#ifndef PNG_NO_WRITE_pHYs
-#define PNG_WRITE_pHYs_SUPPORTED
+#ifndef PNG_NORETURN
+#  define PNG_NORETURN    /* This function does not return */

 #endif
 #endif

-#ifndef PNG_NO_WRITE_sBIT
-#define PNG_WRITE_sBIT_SUPPORTED
+#ifndef PNG_ALLOCATED
+#  define PNG_ALLOCATED   /* The result of the function is new memory */

 #endif
 #endif

-#ifndef PNG_NO_WRITE_sRGB
-#define PNG_WRITE_sRGB_SUPPORTED
+#ifndef PNG_PRIVATE
+#  define PNG_PRIVATE     /* This is a private libpng function */

 #endif
 #endif

-#ifndef PNG_NO_WRITE_tEXt
-#define PNG_WRITE_tEXt_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_tIME
-#define PNG_WRITE_tIME_SUPPORTED
-#endif
-#ifndef PNG_NO_WRITE_tRNS
-#define PNG_WRITE_tRNS_SUPPORTED
+#ifndef PNG_FP_EXPORT     /* A floating point API. */
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+#     define PNG_FP_EXPORT(ordinal, type, name, args)\
+         PNG_EXPORT(ordinal, type, name, args)
+#  else                   /* No floating point APIs */
+#     define PNG_FP_EXPORT(ordinal, type, name, args)
+#  endif

 #endif
 #endif

-#ifndef PNG_NO_WRITE_zTXt
-#define PNG_WRITE_zTXt_SUPPORTED
+#ifndef PNG_FIXED_EXPORT  /* A fixed point API. */
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+#     define PNG_FIXED_EXPORT(ordinal, type, name, args)\
+         PNG_EXPORT(ordinal, type, name, args)
+#  else                   /* No fixed point APIs */
+#     define PNG_FIXED_EXPORT(ordinal, type, name, args)
+#  endif

 #endif
 #endif

-#endif /* PNG_WRITE_ANCILLARY_CHUNKS_SUPPORTED */

 
 

-/* need the time information for reading tIME chunks */
-#if defined(PNG_READ_tIME_SUPPORTED) || defined(PNG_WRITE_tIME_SUPPORTED)
-#include <time.h>
+/* The following uses const char * instead of char * for error
+ * and warning message functions, so some compilers won't complain.
+ * If you do not want to use const, define PNG_NO_CONST here.
+ *
+ * This should not change how the APIs are called, so it can be done
+ * on a per-file basis in the application.
+ */
+#ifndef PNG_CONST
+#  ifndef PNG_NO_CONST
+#    define PNG_CONST const
+#  else
+#    define PNG_CONST
+#  endif

 #endif
 
 /* Some typedefs to get us started.  These should be safe on most of the
 #endif
 
 /* Some typedefs to get us started.  These should be safe on most of the


@@ -540,22 +438,29 @@ __dont__ include it again
  * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
  * don't have to be exactly that size.  Some compilers dislike passing
  * unsigned shorts as function parameters, so you may be better off using
  * numbers suggest (a png_uint_32 must be at least 32 bits long), but they
  * don't have to be exactly that size.  Some compilers dislike passing
  * unsigned shorts as function parameters, so you may be better off using

- * unsigned int for png_uint_16.  Likewise, for 64-bit systems, you may
- * want to have unsigned int for png_uint_32 instead of unsigned long.
+ * unsigned int for png_uint_16.

  */
 
  */
 

+#if defined(INT_MAX) && (INT_MAX > 0x7ffffffeL)
+typedef unsigned int png_uint_32;
+typedef int png_int_32;
+#else

 typedef unsigned long png_uint_32;
 typedef long png_int_32;
 typedef unsigned long png_uint_32;
 typedef long png_int_32;

+#endif

 typedef unsigned short png_uint_16;
 typedef short png_int_16;
 typedef unsigned char png_byte;
 
 typedef unsigned short png_uint_16;
 typedef short png_int_16;
 typedef unsigned char png_byte;
 

-/* This is usually size_t.  It is typedef'ed just in case you need it to
-   change (I'm not sure if you will or not, so I thought I'd be safe) */
+#ifdef PNG_NO_SIZE_T
+typedef unsigned int png_size_t;
+#else

 typedef size_t png_size_t;
 typedef size_t png_size_t;

+#endif
+#define png_sizeof(x) (sizeof (x))

 
 /* The following is needed for medium model support.  It cannot be in the
 
 /* The following is needed for medium model support.  It cannot be in the

- * PNG_INTERNAL section.  Needs modification for other compilers besides
+ * pngpriv.h header.  Needs modification for other compilers besides

  * MSC.  Model independent support declares all arrays and pointers to be
  * large using the far keyword.  The zlib version used must also support
  * model independent data.  As of version zlib 1.0.4, the necessary changes
  * MSC.  Model independent support declares all arrays and pointers to be
  * large using the far keyword.  The zlib version used must also support
  * model independent data.  As of version zlib 1.0.4, the necessary changes


@@ -564,30 +469,29 @@ typedef size_t png_size_t;
  */
 
 /* Separate compiler dependencies (problem here is that zlib.h always
  */
 
 /* Separate compiler dependencies (problem here is that zlib.h always

-   defines FAR. (SJT) */
-#ifdef __BORLANDC__
-#if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
-#define LDATA 1
-#else
-#define LDATA 0
-#endif
-
-#if !defined(__WIN32__) && !defined(__FLAT__)
-#define PNG_MAX_MALLOC_64K
-#if (LDATA != 1)
-#ifndef FAR
-#define FAR __far
-#endif
-#define USE_FAR_KEYWORD
-#endif   /* LDATA != 1 */
-
-/* Possibly useful for moving data out of default segment.
- * Uncomment it if you want. Could also define FARDATA as
- * const if your compiler supports it. (SJT)
-#  define FARDATA FAR
+ * defines FAR. (SJT)

  */
  */

-#endif  /* __WIN32__, __FLAT__ */
-
+#ifdef __BORLANDC__
+#  if defined(__LARGE__) || defined(__HUGE__) || defined(__COMPACT__)
+#    define LDATA 1
+#  else
+#    define LDATA 0
+#  endif
+  /* GRR:  why is Cygwin in here?  Cygwin is not Borland C... */
+#  if !defined(__WIN32__) && !defined(__FLAT__) && !defined(__CYGWIN__)
+#    define PNG_MAX_MALLOC_64K /* only used in build */
+#    if (LDATA != 1)
+#      ifndef FAR
+#        define FAR __far
+#      endif
+#      define USE_FAR_KEYWORD
+#    endif   /* LDATA != 1 */
+         /* Possibly useful for moving data out of default segment.
+          * Uncomment it if you want. Could also define FARDATA as
+          * const if your compiler supports it. (SJT)
+#        define FARDATA FAR
+          */
+#  endif  /* __WIN32__, __FLAT__, __CYGWIN__ */

 #endif   /* __BORLANDC__ */
 
 
 #endif   /* __BORLANDC__ */
 
 


@@ -597,34 +501,57 @@ typedef size_t png_size_t;
  */
 
 /* MSC Medium model */
  */
 
 /* MSC Medium model */

-#if defined(FAR)
-#  if defined(M_I86MM)
-#     define USE_FAR_KEYWORD
-#     define FARDATA FAR
-#     include <dos.h>
+#ifdef FAR
+#  ifdef M_I86MM
+#    define USE_FAR_KEYWORD
+#    define FARDATA FAR
+#    include <dos.h>

 #  endif
 #endif
 
 /* SJT: default case */
 #ifndef FAR
 #  endif
 #endif
 
 /* SJT: default case */
 #ifndef FAR

-#   define FAR
+#  define FAR

 #endif
 
 /* At this point FAR is always defined */
 #ifndef FARDATA
 #endif
 
 /* At this point FAR is always defined */
 #ifndef FARDATA

-#define FARDATA
+#  define FARDATA

 #endif
 
 #endif
 

+/* Typedef for floating-point numbers that are converted
+ * to fixed-point with a multiple of 100,000, e.g., gamma
+ */
+typedef png_int_32 png_fixed_point;
+

 /* Add typedefs for pointers */
 /* Add typedefs for pointers */

-typedef void            FAR * png_voidp;
-typedef png_byte        FAR * png_bytep;
-typedef png_uint_32     FAR * png_uint_32p;
-typedef png_int_32      FAR * png_int_32p;
-typedef png_uint_16     FAR * png_uint_16p;
-typedef png_int_16      FAR * png_int_16p;
-typedef PNG_CONST char  FAR * png_const_charp;
-typedef char            FAR * png_charp;
-typedef double          FAR * png_doublep;
+typedef void                      FAR * png_voidp;
+typedef PNG_CONST void            FAR * png_const_voidp;
+typedef png_byte                  FAR * png_bytep;
+typedef PNG_CONST png_byte        FAR * png_const_bytep;
+typedef png_uint_32               FAR * png_uint_32p;
+typedef PNG_CONST png_uint_32     FAR * png_const_uint_32p;
+typedef png_int_32                FAR * png_int_32p;
+typedef PNG_CONST png_int_32      FAR * png_const_int_32p;
+typedef png_uint_16               FAR * png_uint_16p;
+typedef PNG_CONST png_uint_16     FAR * png_const_uint_16p;
+typedef png_int_16                FAR * png_int_16p;
+typedef PNG_CONST png_int_16      FAR * png_const_int_16p;
+typedef char                      FAR * png_charp;
+typedef PNG_CONST char            FAR * png_const_charp;
+typedef png_fixed_point           FAR * png_fixed_point_p;
+typedef PNG_CONST png_fixed_point FAR * png_const_fixed_point_p;
+typedef png_size_t                FAR * png_size_tp;
+typedef PNG_CONST png_size_t      FAR * png_const_size_tp;
+
+#ifdef PNG_STDIO_SUPPORTED
+typedef FILE            * png_FILE_p;
+#endif
+
+#ifdef PNG_FLOATING_POINT_SUPPORTED
+typedef double           FAR * png_doublep;
+typedef PNG_CONST double FAR * png_const_doublep;
+#endif

 
 /* Pointers to pointers; i.e. arrays */
 typedef png_byte        FAR * FAR * png_bytepp;
 
 /* Pointers to pointers; i.e. arrays */
 typedef png_byte        FAR * FAR * png_bytepp;


@@ -634,72 +561,40 @@ typedef png_uint_16     FAR * FAR * png_uint_16pp;
 typedef png_int_16      FAR * FAR * png_int_16pp;
 typedef PNG_CONST char  FAR * FAR * png_const_charpp;
 typedef char            FAR * FAR * png_charpp;
 typedef png_int_16      FAR * FAR * png_int_16pp;
 typedef PNG_CONST char  FAR * FAR * png_const_charpp;
 typedef char            FAR * FAR * png_charpp;

+typedef png_fixed_point FAR * FAR * png_fixed_point_pp;
+#ifdef PNG_FLOATING_POINT_SUPPORTED

 typedef double          FAR * FAR * png_doublepp;
 typedef double          FAR * FAR * png_doublepp;

-
-/* Pointers to pointers to pointers; i.e. pointer to array */
-typedef char            FAR * FAR * FAR * png_charppp;
-
-/* libpng typedefs for types in zlib. If zlib changes
- * or another compression library is used, then change these.
- * Eliminates need to change all the source files.
- */
-typedef charf *         png_zcharp;
-typedef charf * FAR *   png_zcharpp;
-typedef z_stream 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
-
-/* allow for compilation as shared lib under BeOS */
-#ifdef __BEOSDLL__
-#define PNG_EXPORT(type,symbol) __declspec(export) type symbol

 #endif
 
 #endif
 

-#ifndef PNG_EXPORT
-#define PNG_EXPORT(type,symbol) type symbol
-#endif
-
-
-/* User may want to use these so not in PNG_INTERNAL. Any library functions
- * that are passed far data must be model independent.
- */
-
-#if defined(USE_FAR_KEYWORD)  /* memory model independent fns */
-/* use this to make far-to-near assignments */
-#   define CHECK   1
-#   define NOCHECK 0
-#   define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
-#   define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
-#   define png_strcpy _fstrcpy
-#   define png_strlen _fstrlen
-#   define png_memcmp _fmemcmp      /* SJT: added */
-#   define png_memcpy _fmemcpy
-#   define png_memset _fmemset
-#else /* use the usual functions */
-#   define CVT_PTR(ptr)         (ptr)
-#   define CVT_PTR_NOCHECK(ptr) (ptr)
-#   define png_strcpy strcpy
-#   define png_strlen strlen
-#   define png_memcmp memcmp     /* SJT: added */
-#   define png_memcpy memcpy
-#   define png_memset memset
-#endif
-/* End of memory model independent support */
+/* Pointers to pointers to pointers; i.e., pointer to array */
+typedef char            FAR * FAR * FAR * png_charppp;

 
 

-/* Just a double check that someone hasn't tried to define something
- * contradictory.
+/* png_alloc_size_t is guaranteed to be no smaller than png_size_t,
+ * and no smaller than png_uint_32.  Casts from png_size_t or png_uint_32
+ * to png_alloc_size_t are not necessary; in fact, it is recommended
+ * not to use them at all so that the compiler can complain when something
+ * turns out to be problematic.
+ * Casts in the other direction (from png_alloc_size_t to png_size_t or
+ * png_uint_32) should be explicitly applied; however, we do not expect
+ * to encounter practical situations that require such conversions.

  */
  */

-#if (PNG_ZBUF_SIZE > 65536) && defined(PNG_MAX_MALLOC_64K)
-#undef PNG_ZBUF_SIZE
-#define PNG_ZBUF_SIZE 65536
+#if defined(__TURBOC__) && !defined(__FLAT__)
+   typedef unsigned long png_alloc_size_t;
+#else
+#  if defined(_MSC_VER) && defined(MAXSEG_64K)
+     typedef unsigned long    png_alloc_size_t;
+#  else
+     /* This is an attempt to detect an old Windows system where (int) is
+      * actually 16 bits, in that case png_malloc must have an argument with a
+      * bigger size to accomodate the requirements of the library.
+      */
+#    if (defined(_Windows) || defined(_WINDOWS) || defined(_WINDOWS_)) && \
+        (!defined(INT_MAX) || INT_MAX <= 0x7ffffffeL)
+       typedef DWORD         png_alloc_size_t;
+#    else
+       typedef png_size_t    png_alloc_size_t;
+#    endif
+#  endif

 #endif
 
 #endif /* PNGCONF_H */
 #endif
 
 #endif /* PNGCONF_H */

-