XFA: Upgrade libpng to 1.6.20.

third_party/lpng_v163/pngpriv.h

-
-/* pngpriv.h - private declarations for use inside libpng
- *
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2013 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.)
- *
- * Last changed in libpng 1.6.3 [July 18, 2013]
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- */
-
-/* The symbols declared in this file (including the functions declared
- * as extern) are PRIVATE.  They are not part of the libpng public
- * interface, and are not recommended for use by regular applications.
- * Some of them may become public in the future; others may stay private,
- * change in an incompatible way, or even disappear.
- * Although the libpng users are not forbidden to include this header,
- * they should be well aware of the issues that may arise from doing so.
- */
-
-#ifndef PNGPRIV_H
-#define PNGPRIV_H
-
-/* Feature Test Macros.  The following are defined here to ensure that correctly
- * implemented libraries reveal the APIs libpng needs to build and hide those
- * that are not needed and potentially damaging to the compilation.
- *
- * Feature Test Macros must be defined before any system header is included (see
- * POSIX 1003.1 2.8.2 "POSIX Symbols."
- *
- * These macros only have an effect if the operating system supports either
- * POSIX 1003.1 or C99, or both.  On other operating systems (particularly
- * Windows/Visual Studio) there is no effect; the OS specific tests below are
- * still required (as of 2011-05-02.)
- */
-#define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
-
-#ifndef PNG_VERSION_INFO_ONLY
-/* Standard library headers not required by png.h: */
-#  include <stdlib.h>
-#  include <string.h>
-#endif
-
-#define PNGLIB_BUILD /*libpng is being built, not used*/
-
-/* If HAVE_CONFIG_H is defined during the build then the build system must
- * provide an appropriate "config.h" file on the include path.  The header file
- * must provide definitions as required below (search for "HAVE_CONFIG_H");
- * see configure.ac for more details of the requirements.  The macro
- * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on
- * 'configure'; define this macro to prevent the configure build including the
- * configure generated config.h.  Libpng is expected to compile without *any*
- * special build system support on a reasonably ANSI-C compliant system.
- */
-#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
-#  include <config.h>
-
-   /* Pick up the definition of 'restrict' from config.h if it was read: */
-#  define PNG_RESTRICT restrict
-#endif
-
-/* To support symbol prefixing it is necessary to know *before* including png.h
- * whether the fixed point (and maybe other) APIs are exported, because if they
- * are not internal definitions may be required.  This is handled below just
- * before png.h is included, but load the configuration now if it is available.
- */
-#ifndef PNGLCONF_H
-#  include "pnglibconf.h"
-#endif
-
-/* Local renames may change non-exported API functions from png.h */
-#if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
-#  include "pngprefix.h"
-#endif
-
-#ifdef PNG_USER_CONFIG
-#  include "pngusr.h"
-   /* These should have been defined in pngusr.h */
-#  ifndef PNG_USER_PRIVATEBUILD
-#    define PNG_USER_PRIVATEBUILD "Custom libpng build"
-#  endif
-#  ifndef PNG_USER_DLLFNAME_POSTFIX
-#    define PNG_USER_DLLFNAME_POSTFIX "Cb"
-#  endif
-#endif
-
-/* Compile time options.
- * =====================
- * In a multi-arch build the compiler may compile the code several times for the
- * same object module, producing different binaries for different architectures.
- * When this happens configure-time setting of the target host options cannot be
- * done and this interferes with the handling of the ARM NEON optimizations, and
- * possibly other similar optimizations.  Put additional tests here; in general
- * this is needed when the same option can be changed at both compile time and
- * run time depending on the target OS (i.e. iOS vs Android.)
- *
- * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
- * this is not possible with certain compilers (Oracle SUN OS CC), as a result
- * it is necessary to ensure that all extern functions that *might* be used
- * regardless of $(CFLAGS) get declared in this file.  The test on __ARM_NEON__
- * below is one example of this behavior because it is controlled by the
- * presence or not of -mfpu=neon on the GCC command line, it is possible to do
- * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
- * do this.
- */
-#ifndef PNG_ARM_NEON_OPT
-   /* ARM NEON optimizations are being controlled by the compiler settings,
-    * typically the target FPU.  If the FPU has been set to NEON (-mfpu=neon
-    * with GCC) then the compiler will define __ARM_NEON__ and we can rely
-    * unconditionally on NEON instructions not crashing, otherwise we must
-    * disable use of NEON instructions:
-    */
-#  ifdef __ARM_NEON__
-#     define PNG_ARM_NEON_OPT 2
-#  else
-#     define PNG_ARM_NEON_OPT 0
-#  endif
-#endif
-
-#if PNG_ARM_NEON_OPT > 0
-   /* NEON optimizations are to be at least considered by libpng, so enable the
-    * callbacks to do this.
-    */
-/*
- * Disabled by sbc since this copy of libpng doesn't contains the arm
- * specific code (e.g. arm/arm_init.c)
- */
-/*#  define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon*/
-#endif
-
-/* Is this a build of a DLL where compilation of the object modules requires
- * different preprocessor settings to those required for a simple library?  If
- * so PNG_BUILD_DLL must be set.
- *
- * If libpng is used inside a DLL but that DLL does not export the libpng APIs
- * PNG_BUILD_DLL must not be set.  To avoid the code below kicking in build a
- * static library of libpng then link the DLL against that.
- */
-#ifndef PNG_BUILD_DLL
-#  ifdef DLL_EXPORT
-      /* This is set by libtool when files are compiled for a DLL; libtool
-       * always compiles twice, even on systems where it isn't necessary.  Set
-       * PNG_BUILD_DLL in case it is necessary:
-       */
-#     define PNG_BUILD_DLL
-#  else
-#     ifdef _WINDLL
-         /* This is set by the Microsoft Visual Studio IDE in projects that
-          * build a DLL.  It can't easily be removed from those projects (it
-          * isn't visible in the Visual Studio UI) so it is a fairly reliable
-          * indication that PNG_IMPEXP needs to be set to the DLL export
-          * attributes.
-          */
-#        define PNG_BUILD_DLL
-#     else
-#        ifdef __DLL__
-            /* This is set by the Borland C system when compiling for a DLL
-             * (as above.)
-             */
-#           define PNG_BUILD_DLL
-#        else
-            /* Add additional compiler cases here. */
-#        endif
-#     endif
-#  endif
-#endif /* Setting PNG_BUILD_DLL if required */
-
-/* See pngconf.h for more details: the builder of the library may set this on
- * the command line to the right thing for the specific compilation system or it
- * may be automagically set above (at present we know of no system where it does
- * need to be set on the command line.)
- *
- * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
- * setting it to the "import" setting for a DLL build.
- */
-#ifndef PNG_IMPEXP
-#  ifdef PNG_BUILD_DLL
-#     define PNG_IMPEXP PNG_DLL_EXPORT
-#  else
-      /* Not building a DLL, or the DLL doesn't require specific export
-       * definitions.
-       */
-#     define PNG_IMPEXP
-#  endif
-#endif
-
-/* No warnings for private or deprecated functions in the build: */
-#ifndef PNG_DEPRECATED
-#  define PNG_DEPRECATED
-#endif
-#ifndef PNG_PRIVATE
-#  define PNG_PRIVATE
-#endif
-
-/* Symbol preprocessing support.
- *
- * To enable listing global, but internal, symbols the following macros should
- * always be used to declare an extern data or function object in this file.
- */
-#ifndef PNG_INTERNAL_DATA
-#  define PNG_INTERNAL_DATA(type, name, array) extern type name array
-#endif
-
-#ifndef PNG_INTERNAL_FUNCTION
-#  define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
-      extern PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
-#endif
-
-/* If floating or fixed point APIs are disabled they may still be compiled
- * internally.  To handle this make sure they are declared as the appropriate
- * internal extern function (otherwise the symbol prefixing stuff won't work and
- * the functions will be used without definitions.)
- *
- * NOTE: although all the API functions are declared here they are not all
- * actually built!  Because the declarations are still made it is necessary to
- * fake out types that they depend on.
- */
-#ifndef PNG_FP_EXPORT
-#  ifndef PNG_FLOATING_POINT_SUPPORTED
-#     define PNG_FP_EXPORT(ordinal, type, name, args)\
-         PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
-#     ifndef PNG_VERSION_INFO_ONLY
-         typedef struct png_incomplete png_double;
-         typedef png_double*           png_doublep;
-         typedef const png_double*     png_const_doublep;
-         typedef png_double**          png_doublepp;
-#     endif
-#  endif
-#endif
-#ifndef PNG_FIXED_EXPORT
-#  ifndef PNG_FIXED_POINT_SUPPORTED
-#     define PNG_FIXED_EXPORT(ordinal, type, name, args)\
-         PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
-#  endif
-#endif
-
-#include "png.h"
-
-/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
-#ifndef PNG_DLL_EXPORT
-#  define PNG_DLL_EXPORT
-#endif
-
-/* SECURITY and SAFETY:
- *
- * By default libpng is built without any internal limits on image size,
- * individual heap (png_malloc) allocations or the total amount of memory used.
- * If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used
- * (unless individually overridden).  These limits are believed to be fairly
- * safe, but builders of secure systems should verify the values against the
- * real system capabilities.
- */
-#ifdef PNG_SAFE_LIMITS_SUPPORTED
-   /* 'safe' limits */
-#  ifndef PNG_USER_WIDTH_MAX
-#     define PNG_USER_WIDTH_MAX 1000000
-#  endif
-#  ifndef PNG_USER_HEIGHT_MAX
-#     define PNG_USER_HEIGHT_MAX 1000000
-#  endif
-#  ifndef PNG_USER_CHUNK_CACHE_MAX
-#     define PNG_USER_CHUNK_CACHE_MAX 128
-#  endif
-#  ifndef PNG_USER_CHUNK_MALLOC_MAX
-#     define PNG_USER_CHUNK_MALLOC_MAX 8000000
-#  endif
-#else
-   /* values for no limits */
-#  ifndef PNG_USER_WIDTH_MAX
-#     define PNG_USER_WIDTH_MAX 0x7fffffff
-#  endif
-#  ifndef PNG_USER_HEIGHT_MAX
-#     define PNG_USER_HEIGHT_MAX 0x7fffffff
-#  endif
-#  ifndef PNG_USER_CHUNK_CACHE_MAX
-#     define PNG_USER_CHUNK_CACHE_MAX 0
-#  endif
-#  ifndef PNG_USER_CHUNK_MALLOC_MAX
-#     define PNG_USER_CHUNK_MALLOC_MAX 0
-#  endif
-#endif
-
-/* Moved to pngpriv.h at libpng-1.5.0 */
-/* NOTE: some of these may have been used in external applications as
- * these definitions were exposed in pngconf.h prior to 1.5.
- */
-
-/* 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.
- *
- * zlib provides 'MAXSEG_64K' which, if defined, indicates the
- * same limit and pngconf.h (already included) sets the limit
- * if certain operating systems are detected.
- */
-#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
-#  define PNG_MAX_MALLOC_64K
-#endif
-
-#ifndef PNG_UNUSED
-/* Unused formal parameter warnings are silenced using the following macro
- * which is expected to have no bad effects on performance (optimizing
- * compilers will probably remove it entirely).  Note that if you replace
- * it with something other than whitespace, you must include the terminating
- * semicolon.
- */
-#  define PNG_UNUSED(param) (void)param;
-#endif
-
-/* Just a little check that someone hasn't tried to define something
- * contradictory.
- */
-#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
-#  undef PNG_ZBUF_SIZE
-#  define PNG_ZBUF_SIZE 65536L
-#endif
-
-/* If warnings or errors are turned off the code is disabled or redirected here.
- * From 1.5.4 functions have been added to allow very limited formatting of
- * error and warning messages - this code will also be disabled here.
- */
-#ifdef PNG_WARNINGS_SUPPORTED
-#  define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
-#else
-#  define png_warning(s1,s2) ((void)(s1))
-#  define png_chunk_warning(s1,s2) ((void)(s1))
-#  define png_warning_parameter(p,number,string) ((void)0)
-#  define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
-#  define png_warning_parameter_signed(p,number,format,value) ((void)0)
-#  define png_formatted_warning(pp,p,message) ((void)(pp))
-#  define PNG_WARNING_PARAMETERS(p)
-#endif
-#ifndef PNG_ERROR_TEXT_SUPPORTED
-#  define png_error(s1,s2) png_err(s1)
-#  define png_chunk_error(s1,s2) png_err(s1)
-#  define png_fixed_error(s1,s2) png_err(s1)
-#endif
-
-/* C allows up-casts from (void*) to any pointer and (const void*) to any
- * pointer to a const object.  C++ regards this as a type error and requires an
- * explicit, static, cast and provides the static_cast<> rune to ensure that
- * const is not cast away.
- */
-#ifdef __cplusplus
-#  define png_voidcast(type, value) static_cast<type>(value)
-#  define png_constcast(type, value) const_cast<type>(value)
-#  define png_aligncast(type, value) \
-   static_cast<type>(static_cast<void*>(value))
-#  define png_aligncastconst(type, value) \
-   static_cast<type>(static_cast<const void*>(value))
-#else
-#  define png_voidcast(type, value) (value)
-#  define png_constcast(type, value) ((type)(value))
-#  define png_aligncast(type, value) ((void*)(value))
-#  define png_aligncastconst(type, value) ((const void*)(value))
-#endif /* __cplusplus */
-
-/* Some fixed point APIs are still required even if not exported because
- * they get used by the corresponding floating point APIs.  This magic
- * deals with this:
- */
-#ifdef PNG_FIXED_POINT_SUPPORTED
-#  define PNGFAPI PNGAPI
-#else
-#  define PNGFAPI /* PRIVATE */
-#endif
-
-#ifndef PNG_VERSION_INFO_ONLY
-/* Other defines specific to compilers can go here.  Try to keep
- * them inside an appropriate ifdef/endif pair for portability.
- */
-#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
-    defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
-   /* png.c requires the following ANSI-C constants if the conversion of
-    * floating point to ASCII is implemented therein:
-    *
-    *  DBL_DIG  Maximum number of decimal digits (can be set to any constant)
-    *  DBL_MIN  Smallest normalized fp number (can be set to an arbitrary value)
-    *  DBL_MAX  Maximum floating point number (can be set to an arbitrary value)
-    */
-#  include <float.h>
-
-#  if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
-    defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
-     /* 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(_AMIGA) && defined(__SASC) && defined(_M68881)
-     /* Amiga SAS/C: We must include builtin FPU functions when compiling using
-      * MATH=68881
-      */
-#    include <m68881.h>
-#  endif
-#endif
-
-/* This provides the non-ANSI (far) memory allocation routines. */
-#if defined(__TURBOC__) && defined(__MSDOS__)
-#  include <mem.h>
-#  include <alloc.h>
-#endif
-
-#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
-    defined(_WIN32) || defined(__WIN32__)
-#  include <windows.h>  /* defines _WINDOWS_ macro */
-#endif
-#endif /* PNG_VERSION_INFO_ONLY */
-
-/* Moved here around 1.5.0beta36 from pngconf.h */
-/* Users may want to use these so they are not private.  Any library
- * functions that are passed far data must be model-independent.
- */
-
-/* Memory model/platform independent fns */
-#ifndef PNG_ABORT
-#  ifdef _WINDOWS_
-#    define PNG_ABORT() ExitProcess(0)
-#  else
-#    define PNG_ABORT() abort()
-#  endif
-#endif
-
-/* These macros may need to be architecture dependent. */
-#define PNG_ALIGN_NONE   0 /* do not use data alignment */
-#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
-#ifdef offsetof
-#  define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
-#else
-#  define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
-#endif
-#define PNG_ALIGN_SIZE   3 /* use sizeof to determine alignment */
-
-#ifndef PNG_ALIGN_TYPE
-   /* Default to using aligned access optimizations and requiring alignment to a
-    * multiple of the data type size.  Override in a compiler specific fashion
-    * if necessary by inserting tests here:
-    */
-#  define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
-#endif
-
-#if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
-   /* This is used because in some compiler implementations non-aligned
-    * structure members are supported, so the offsetof approach below fails.
-    * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
-    * is good for performance.  Do not do this unless you have tested the result
-    * and understand it.
-    */
-#  define png_alignof(type) (sizeof (type))
-#else
-#  if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
-#     define png_alignof(type) offsetof(struct{char c; type t;}, t)
-#  else
-#     if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
-#        define png_alignof(type) (1)
-#     endif
-      /* Else leave png_alignof undefined to prevent use thereof */
-#  endif
-#endif
-
-/* This implicitly assumes alignment is always to a power of 2. */
-#ifdef png_alignof
-#  define png_isaligned(ptr, type)\
-   ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
-#else
-#  define png_isaligned(ptr, type) 0
-#endif
-
-/* End of memory model/platform independent support */
-/* End of 1.5.0beta36 move from pngconf.h */
-
-/* CONSTANTS and UTILITY MACROS
- * These are used internally by libpng and not exposed in the API
- */
-
-/* Various modes of operation.  Note that after an init, mode is set to
- * zero automatically when the structure is created.  Three of these
- * are defined in png.h because they need to be visible to applications
- * that call png_set_unknown_chunk().
- */
-/* #define PNG_HAVE_IHDR            0x01 (defined in png.h) */
-/* #define PNG_HAVE_PLTE            0x02 (defined in png.h) */
-#define PNG_HAVE_IDAT               0x04
-/* #define PNG_AFTER_IDAT           0x08 (defined in png.h) */
-#define PNG_HAVE_IEND               0x10
-                   /*               0x20 (unused) */
-                   /*               0x40 (unused) */
-                   /*               0x80 (unused) */
-#define PNG_HAVE_CHUNK_HEADER      0x100
-#define PNG_WROTE_tIME             0x200
-#define PNG_WROTE_INFO_BEFORE_PLTE 0x400
-#define PNG_BACKGROUND_IS_GRAY     0x800
-#define PNG_HAVE_PNG_SIGNATURE    0x1000
-#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
-                   /*             0x4000 (unused) */
-#define PNG_IS_READ_STRUCT        0x8000 /* Else is a write struct */
-
-/* Flags for the transformations the PNG library does on the image data */
-#define PNG_BGR                 0x0001
-#define PNG_INTERLACE           0x0002
-#define PNG_PACK                0x0004
-#define PNG_SHIFT               0x0008
-#define PNG_SWAP_BYTES          0x0010
-#define PNG_INVERT_MONO         0x0020
-#define PNG_QUANTIZE            0x0040
-#define PNG_COMPOSE             0x0080     /* Was PNG_BACKGROUND */
-#define PNG_BACKGROUND_EXPAND   0x0100
-#define PNG_EXPAND_16           0x0200     /* Added to libpng 1.5.2 */
-#define PNG_16_TO_8             0x0400     /* Becomes 'chop' in 1.5.4 */
-#define PNG_RGBA                0x0800
-#define PNG_EXPAND              0x1000
-#define PNG_GAMMA               0x2000
-#define PNG_GRAY_TO_RGB         0x4000
-#define PNG_FILLER              0x8000
-#define PNG_PACKSWAP           0x10000
-#define PNG_SWAP_ALPHA         0x20000
-#define PNG_STRIP_ALPHA        0x40000
-#define PNG_INVERT_ALPHA       0x80000
-#define PNG_USER_TRANSFORM    0x100000
-#define PNG_RGB_TO_GRAY_ERR   0x200000
-#define PNG_RGB_TO_GRAY_WARN  0x400000
-#define PNG_RGB_TO_GRAY       0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
-#define PNG_ENCODE_ALPHA      0x800000 /* Added to libpng-1.5.4 */
-#define PNG_ADD_ALPHA         0x1000000 /* Added to libpng-1.2.7 */
-#define PNG_EXPAND_tRNS       0x2000000 /* Added to libpng-1.2.9 */
-#define PNG_SCALE_16_TO_8     0x4000000 /* Added to libpng-1.5.4 */
-                       /*   0x8000000 unused */
-                       /*  0x10000000 unused */
-                       /*  0x20000000 unused */
-                       /*  0x40000000 unused */
-/* Flags for png_create_struct */
-#define PNG_STRUCT_PNG   0x0001
-#define PNG_STRUCT_INFO  0x0002
-
-/* Scaling factor for filter heuristic weighting calculations */
-#define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
-#define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
-
-/* Flags for the png_ptr->flags rather than declaring a byte for each one */
-#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY     0x0001
-#define PNG_FLAG_ZSTREAM_INITIALIZED      0x0002 /* Added to libpng-1.6.0 */
-                                  /*      0x0004    unused */
-#define PNG_FLAG_ZSTREAM_ENDED            0x0008 /* Added to libpng-1.6.0 */
-                                  /*      0x0010    unused */
-                                  /*      0x0020    unused */
-#define PNG_FLAG_ROW_INIT                 0x0040
-#define PNG_FLAG_FILLER_AFTER             0x0080
-#define PNG_FLAG_CRC_ANCILLARY_USE        0x0100
-#define PNG_FLAG_CRC_ANCILLARY_NOWARN     0x0200
-#define PNG_FLAG_CRC_CRITICAL_USE         0x0400
-#define PNG_FLAG_CRC_CRITICAL_IGNORE      0x0800
-#define PNG_FLAG_ASSUME_sRGB              0x1000 /* Added to libpng-1.5.4 */
-#define PNG_FLAG_OPTIMIZE_ALPHA           0x2000 /* Added to libpng-1.5.4 */
-#define PNG_FLAG_DETECT_UNINITIALIZED     0x4000 /* Added to libpng-1.5.4 */
-/* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS      0x8000 */
-/* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS      0x10000 */
-#define PNG_FLAG_LIBRARY_MISMATCH        0x20000
-#define PNG_FLAG_STRIP_ERROR_NUMBERS     0x40000
-#define PNG_FLAG_STRIP_ERROR_TEXT        0x80000
-#define PNG_FLAG_BENIGN_ERRORS_WARN     0x100000 /* Added to libpng-1.4.0 */
-#define PNG_FLAG_APP_WARNINGS_WARN      0x200000 /* Added to libpng-1.6.0 */
-#define PNG_FLAG_APP_ERRORS_WARN        0x400000 /* Added to libpng-1.6.0 */
-                                  /*    0x800000    unused */
-                                  /*   0x1000000    unused */
-                                  /*   0x2000000    unused */
-                                  /*   0x4000000    unused */
-                                  /*   0x8000000    unused */
-                                  /*  0x10000000    unused */
-                                  /*  0x20000000    unused */
-                                  /*  0x40000000    unused */
-
-#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
-                                     PNG_FLAG_CRC_ANCILLARY_NOWARN)
-
-#define PNG_FLAG_CRC_CRITICAL_MASK  (PNG_FLAG_CRC_CRITICAL_USE | \
-                                     PNG_FLAG_CRC_CRITICAL_IGNORE)
-
-#define PNG_FLAG_CRC_MASK           (PNG_FLAG_CRC_ANCILLARY_MASK | \
-                                     PNG_FLAG_CRC_CRITICAL_MASK)
-
-/* Save typing and make code easier to understand */
-
-#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
-   abs((int)((c1).green) - (int)((c2).green)) + \
-   abs((int)((c1).blue) - (int)((c2).blue)))
-
-/* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
- * by dividing by 257 *with rounding*.  This macro is exact for the given range.
- * See the discourse in pngrtran.c png_do_scale_16_to_8.  The values in the
- * macro were established by experiment (modifying the added value).  The macro
- * has a second variant that takes a value already scaled by 255 and divides by
- * 65535 - this has a maximum error of .502.  Over the range 0..65535*65535 it
- * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
- */
-#define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
-#define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
-
-/* Added to libpng-1.2.6 JB */
-#define PNG_ROWBYTES(pixel_bits, width) \
-    ((pixel_bits) >= 8 ? \
-    ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
-    (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
-
-/* PNG_OUT_OF_RANGE returns true if value is outside the range
- * ideal-delta..ideal+delta.  Each argument is evaluated twice.
- * "ideal" and "delta" should be constants, normally simple
- * integers, "value" a variable. Added to libpng-1.2.6 JB
- */
-#define PNG_OUT_OF_RANGE(value, ideal, delta) \
-   ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
-
-/* Conversions between fixed and floating point, only defined if
- * required (to make sure the code doesn't accidentally use float
- * when it is supposedly disabled.)
- */
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-/* The floating point conversion can't overflow, though it can and
- * does lose accuracy relative to the original fixed point value.
- * In practice this doesn't matter because png_fixed_point only
- * stores numbers with very low precision.  The png_ptr and s
- * arguments are unused by default but are there in case error
- * checking becomes a requirement.
- */
-#define png_float(png_ptr, fixed, s) (.00001 * (fixed))
-
-/* The fixed point conversion performs range checking and evaluates
- * its argument multiple times, so must be used with care.  The
- * range checking uses the PNG specification values for a signed
- * 32 bit fixed point value except that the values are deliberately
- * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
- * (2^31-1) * 100000). 's' is a string that describes the value being
- * converted.
- *
- * NOTE: this macro will raise a png_error if the range check fails,
- * therefore it is normally only appropriate to use this on values
- * that come from API calls or other sources where an out of range
- * error indicates a programming error, not a data error!
- *
- * NOTE: by default this is off - the macro is not used - because the
- * function call saves a lot of code.
- */
-#ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
-#define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
-    ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
-#endif
-/* else the corresponding function is defined below, inside the scope of the
- * cplusplus test.
- */
-#endif
-
-/* Constants for known chunk types.  If you need to add a chunk, define the name
- * here.  For historical reasons these constants have the form png_<name>; i.e.
- * the prefix is lower case.  Please use decimal values as the parameters to
- * match the ISO PNG specification and to avoid relying on the C locale
- * interpretation of character values.
- *
- * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
- * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
- * to be generated if required.
- *
- * PNG_32b correctly produces a value shifted by up to 24 bits, even on
- * architectures where (int) is only 16 bits.
- */
-#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
-#define PNG_U32(b1,b2,b3,b4) \
-   (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
-
-/* Constants for known chunk types.
- *
- * MAINTAINERS: If you need to add a chunk, define the name here.
- * For historical reasons these constants have the form png_<name>; i.e.
- * the prefix is lower case.  Please use decimal values as the parameters to
- * match the ISO PNG specification and to avoid relying on the C locale
- * interpretation of character values.  Please keep the list sorted.
- *
- * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
- * type.  In fact the specification does not express chunk types this way,
- * however using a 32-bit value means that the chunk type can be read from the
- * stream using exactly the same code as used for a 32-bit unsigned value and
- * can be examined far more efficiently (using one arithmetic compare).
- *
- * Prior to 1.5.6 the chunk type constants were expressed as C strings.  The
- * libpng API still uses strings for 'unknown' chunks and a macro,
- * PNG_STRING_FROM_CHUNK, allows a string to be generated if required.  Notice
- * that for portable code numeric values must still be used; the string "IHDR"
- * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
- *
- * In 1.7.0 the definitions will be made public in png.h to avoid having to
- * duplicate the same definitions in application code.
- */
-#define png_IDAT PNG_U32( 73,  68,  65,  84)
-#define png_IEND PNG_U32( 73,  69,  78,  68)
-#define png_IHDR PNG_U32( 73,  72,  68,  82)
-#define png_PLTE PNG_U32( 80,  76,  84,  69)
-#define png_bKGD PNG_U32( 98,  75,  71,  68)
-#define png_cHRM PNG_U32( 99,  72,  82,  77)
-#define png_fRAc PNG_U32(102,  82,  65,  99) /* registered, not defined */
-#define png_gAMA PNG_U32(103,  65,  77,  65)
-#define png_gIFg PNG_U32(103,  73,  70, 103)
-#define png_gIFt PNG_U32(103,  73,  70, 116) /* deprecated */
-#define png_gIFx PNG_U32(103,  73,  70, 120)
-#define png_hIST PNG_U32(104,  73,  83,  84)
-#define png_iCCP PNG_U32(105,  67,  67,  80)
-#define png_iTXt PNG_U32(105,  84,  88, 116)
-#define png_oFFs PNG_U32(111,  70,  70, 115)
-#define png_pCAL PNG_U32(112,  67,  65,  76)
-#define png_pHYs PNG_U32(112,  72,  89, 115)
-#define png_sBIT PNG_U32(115,  66,  73,  84)
-#define png_sCAL PNG_U32(115,  67,  65,  76)
-#define png_sPLT PNG_U32(115,  80,  76,  84)
-#define png_sRGB PNG_U32(115,  82,  71,  66)
-#define png_sTER PNG_U32(115,  84,  69,  82)
-#define png_tEXt PNG_U32(116,  69,  88, 116)
-#define png_tIME PNG_U32(116,  73,  77,  69)
-#define png_tRNS PNG_U32(116,  82,  78,  83)
-#define png_zTXt PNG_U32(122,  84,  88, 116)
-
-/* The following will work on (signed char*) strings, whereas the get_uint_32
- * macro will fail on top-bit-set values because of the sign extension.
- */
-#define PNG_CHUNK_FROM_STRING(s)\
-   PNG_U32(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
-
-/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
- * signed and the argument is a (char[])  This macro will fail miserably on
- * systems where (char) is more than 8 bits.
- */
-#define PNG_STRING_FROM_CHUNK(s,c)\
-   (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
-   ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
-
-/* Do the same but terminate with a null character. */
-#define PNG_CSTRING_FROM_CHUNK(s,c)\
-   (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
-
-/* Test on flag values as defined in the spec (section 5.4): */
-#define PNG_CHUNK_ANCILLARY(c)   (1 & ((c) >> 29))
-#define PNG_CHUNK_CRITICAL(c)     (!PNG_CHUNK_ANCILLARY(c))
-#define PNG_CHUNK_PRIVATE(c)      (1 & ((c) >> 21))
-#define PNG_CHUNK_RESERVED(c)     (1 & ((c) >> 13))
-#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >>  5))
-
-/* Gamma values (new at libpng-1.5.4): */
-#define PNG_GAMMA_MAC_OLD 151724  /* Assume '1.8' is really 2.2/1.45! */
-#define PNG_GAMMA_MAC_INVERSE 65909
-#define PNG_GAMMA_sRGB_INVERSE 45455
-
-/* Almost everything below is C specific; the #defines above can be used in
- * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
- */
-#ifndef PNG_VERSION_INFO_ONLY
-
-#include "pngstruct.h"
-#include "pnginfo.h"
-
-/* Validate the include paths - the include path used to generate pnglibconf.h
- * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
- */
-#if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
-#  error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
-      "-I (include path) error: see the notes in pngpriv.h"
-   /* This means that when pnglibconf.h was built the copy of zlib.h that it
-    * used is not the same as the one being used here.  Because the build of
-    * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
-    * zlib version number and because this affects handling of certain broken
-    * PNG files the -I directives must match.
-    *
-    * The most likely explanation is that you passed a -I in CFLAGS, this will
-    * not work; all the preprocessor directories and in particular all the -I
-    * directives must be in CPPFLAGS.
-    */
-#endif
-
-/* This is used for 16 bit gamma tables -- only the top level pointers are
- * const; this could be changed:
- */
-typedef const png_uint_16p * png_const_uint_16pp;
-
-/* Added to libpng-1.5.7: sRGB conversion tables */
-#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
-   defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
-#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
-PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
-   /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
-    * 0..65535.  This table gives the closest 16-bit answers (no errors).
-    */
-#endif
-
-PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
-PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
-
-#define PNG_sRGB_FROM_LINEAR(linear) ((png_byte)((png_sRGB_base[(linear)>>15] +\
-   ((((linear)&0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8))
-   /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
-    * encoded value with maximum error 0.646365.  Note that the input is not a
-    * 16-bit value; it has been multiplied by 255! */
-#endif /* PNG_SIMPLIFIED_READ/WRITE */
-
-
-/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
-/* Internal functions; these are not exported from a DLL however because they
- * are used within several of the C source files they have to be C extern.
- *
- * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
- */
-
-/* Zlib support */
-#define PNG_UNEXPECTED_ZLIB_RETURN (-7)
-PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
-   PNG_EMPTY);
-   /* Used by the zlib handling functions to ensure that z_stream::msg is always
-    * set before they return.
-    */
-
-#ifdef PNG_WRITE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
-   png_compression_bufferp *list),PNG_EMPTY);
-   /* Free the buffer list used by the compressed write code. */
-#endif
-
-#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
-   !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
-   (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
-   defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
-   defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
-   (defined(PNG_sCAL_SUPPORTED) && \
-   defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
-PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
-   double fp, png_const_charp text),PNG_EMPTY);
-#endif
-
-/* Check the user version string for compatibility, returns false if the version
- * numbers aren't compatible.
- */
-PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
-   png_const_charp user_png_ver),PNG_EMPTY);
-
-/* Internal base allocator - no messages, NULL on failure to allocate.  This
- * does, however, call the application provided allocator and that could call
- * png_error (although that would be a bug in the application implementation.)
- */
-PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
-   png_alloc_size_t size),PNG_ALLOCATED);
-
-#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
-   defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
-/* Internal array allocator, outputs no error or warning messages on failure,
- * just returns NULL.  
- */
-PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
-   int nelements, size_t element_size),PNG_ALLOCATED);
-
-/* The same but an existing array is extended by add_elements.  This function
- * also memsets the new elements to 0 and copies the old elements.  The old
- * array is not freed or altered.
- */
-PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
-   png_const_voidp array, int old_elements, int add_elements,
-   size_t element_size),PNG_ALLOCATED);
-#endif /* text, sPLT or unknown chunks */
-
-/* Magic to create a struct when there is no struct to call the user supplied
- * memory allocators.  Because error handling has not been set up the memory
- * handlers can't safely call png_error, but this is an obscure and undocumented
- * restriction so libpng has to assume that the 'free' handler, at least, might
- * call png_error.
- */
-PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
-   (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
-    png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
-    png_free_ptr free_fn),PNG_ALLOCATED);
-
-/* Free memory from internal libpng struct */
-PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
-   PNG_EMPTY);
-
-/* Free an allocated jmp_buf (always succeeds) */
-PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
-
-/* Function to allocate memory for zlib.  PNGAPI is disallowed. */
-PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
-   PNG_ALLOCATED);
-
-/* Function to free memory for zlib.  PNGAPI is disallowed. */
-PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
-
-/* Next four functions are used internally as callbacks.  PNGCBAPI is required
- * but not PNG_EXPORT.  PNGAPI added at libpng version 1.2.3, changed to
- * PNGCBAPI at 1.5.0
- */
-
-PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
-    png_bytep data, png_size_t length),PNG_EMPTY);
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
-    png_bytep buffer, png_size_t length),PNG_EMPTY);
-#endif
-
-PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
-    png_bytep data, png_size_t length),PNG_EMPTY);
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-#  ifdef PNG_STDIO_SUPPORTED
-PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
-   PNG_EMPTY);
-#  endif
-#endif
-
-/* Reset the CRC variable */
-PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
-
-/* Write the "data" buffer to whatever output you are using */
-PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
-    png_const_bytep data, png_size_t length),PNG_EMPTY);
-
-/* Read and check the PNG file signature */
-PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
-   png_inforp info_ptr),PNG_EMPTY);
-
-/* Read the chunk header (length + type name) */
-PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
-   PNG_EMPTY);
-
-/* Read data from whatever input you are using into the "data" buffer */
-PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
-    png_size_t length),PNG_EMPTY);
-
-/* Read bytes into buf, and update png_ptr->crc */
-PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
-    png_uint_32 length),PNG_EMPTY);
-
-/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
-PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
-   png_uint_32 skip),PNG_EMPTY);
-
-/* Read the CRC from the file and compare it to the libpng calculated CRC */
-PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
-
-/* Calculate the CRC over a section of data.  Note that we are only
- * passing a maximum of 64K on systems that have this as a memory limit,
- * since this is the maximum buffer size we can specify.
- */
-PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
-   png_const_bytep ptr, png_size_t length),PNG_EMPTY);
-
-#ifdef PNG_WRITE_FLUSH_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-/* Write various chunks */
-
-/* Write the IHDR chunk, and update the png_struct with the necessary
- * information.
- */
-PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
-   png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
-   int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
-
-PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
-   png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
-
-PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
-   png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
-   PNG_EMPTY);
-
-PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
-
-#ifdef PNG_WRITE_gAMA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
-    png_fixed_point file_gamma),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_sBIT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
-    png_const_color_8p sbit, int color_type),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_cHRM_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
-    const png_xy *xy), PNG_EMPTY);
-    /* The xy value must have been previously validated */
-#endif
-
-#ifdef PNG_WRITE_sRGB_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
-    int intent),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_iCCP_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
-   png_const_charp name, png_const_bytep profile), PNG_EMPTY);
-   /* The profile must have been previously validated for correctness, the
-    * length comes from the first four bytes.  Only the base, deflate,
-    * compression is supported.
-    */
-#endif
-
-#ifdef PNG_WRITE_sPLT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
-    png_const_sPLT_tp palette),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_tRNS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
-    png_const_bytep trans, png_const_color_16p values, int number,
-    int color_type),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_bKGD_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
-    png_const_color_16p values, int color_type),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_hIST_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
-    png_const_uint_16p hist, int num_hist),PNG_EMPTY);
-#endif
-
-/* Chunks that have keywords */
-#ifdef PNG_WRITE_tEXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
-   png_const_charp key, png_const_charp text, png_size_t text_len),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_zTXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
-    key, png_const_charp text, png_size_t text_len, int compression),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_iTXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
-    int compression, png_const_charp key, png_const_charp lang,
-    png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
-#endif
-
-#ifdef PNG_TEXT_SUPPORTED  /* Added at version 1.0.14 and 1.2.4 */
-PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
-    png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_oFFs_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
-    png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_pCAL_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
-    png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
-    png_const_charp units, png_charpp params),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_pHYs_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
-    png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
-    int unit_type),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_tIME_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
-    png_const_timep mod_time),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_sCAL_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
-    int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
-#endif
-
-/* Called when finished processing a row of data */
-PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
-    PNG_EMPTY);
-
-/* Internal use only.   Called before first row of data */
-PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
-    PNG_EMPTY);
-
-/* Combine a row of data, dealing with alpha, etc. if requested.  'row' is an
- * array of png_ptr->width pixels.  If the image is not interlaced or this
- * is the final pass this just does a memcpy, otherwise the "display" flag
- * is used to determine whether to copy pixels that are not in the current pass.
- *
- * Because 'png_do_read_interlace' (below) replicates pixels this allows this
- * function to achieve the documented 'blocky' appearance during interlaced read
- * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
- * are not changed if they are not in the current pass, when display is 0.
- *
- * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
- *
- * The API always reads from the png_struct row buffer and always assumes that
- * it is full width (png_do_read_interlace has already been called.)
- *
- * This function is only ever used to write to row buffers provided by the
- * caller of the relevant libpng API and the row must have already been
- * transformed by the read transformations.
- *
- * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
- * bitmasks for use within the code, otherwise runtime generated masks are used.
- * The default is compile time masks.
- */
-#ifndef PNG_USE_COMPILE_TIME_MASKS
-#  define PNG_USE_COMPILE_TIME_MASKS 1
-#endif
-PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
-    png_bytep row, int display),PNG_EMPTY);
-
-#ifdef PNG_READ_INTERLACING_SUPPORTED
-/* Expand an interlaced row: the 'row_info' describes the pass data that has
- * been read in and must correspond to the pixels in 'row', the pixels are
- * expanded (moved apart) in 'row' to match the final layout, when doing this
- * the pixels are *replicated* to the intervening space.  This is essential for
- * the correct operation of png_combine_row, above.
- */
-PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
-    png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
-#endif
-
-/* GRR TO DO (2.0 or whenever):  simplify other internal calling interfaces */
-
-#ifdef PNG_WRITE_INTERLACING_SUPPORTED
-/* Grab pixels out of a row for an interlaced pass */
-PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
-    png_bytep row, int pass),PNG_EMPTY);
-#endif
-
-/* Unfilter a row: check the filter value before calling this, there is no point
- * calling it for PNG_FILTER_VALUE_NONE.
- */
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
-
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
-    png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
-    row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
-
-/* Choose the best filter to use and filter the row data */
-PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
-    png_row_infop row_info),PNG_EMPTY);
-
-#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
-   png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
-   /* Read 'avail_out' bytes of data from the IDAT stream.  If the output buffer
-    * is NULL the function checks, instead, for the end of the stream.  In this
-    * case a benign error will be issued if the stream end is not found or if
-    * extra data has to be consumed.
-    */
-PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
-   PNG_EMPTY);
-   /* This cleans up when the IDAT LZ stream does not end when the last image
-    * byte is read; there is still some pending input.
-    */
-
-PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
-   PNG_EMPTY);
-   /* Finish a row while reading, dealing with interlacing passes, etc. */
-#endif
-
-/* Initialize the row buffers, etc. */
-PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-/* Optional call to update the users info structure */
-PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-#endif
-
-/* These are the functions that do the transformations */
-#ifdef PNG_READ_FILLER_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_filler,(png_row_infop row_info,
-    png_bytep row, png_uint_32 filler, png_uint_32 flags),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_swap_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_write_swap_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_invert_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_write_invert_alpha,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
-    defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
-    png_bytep row, int at_start),PNG_EMPTY);
-#endif
-
-#ifdef PNG_16BIT_SUPPORTED
-#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-#endif
-
-#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
-    defined(PNG_WRITE_PACKSWAP_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-PNG_INTERNAL_FUNCTION(int,png_do_rgb_to_gray,(png_structrp png_ptr,
-    png_row_infop row_info, png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_gray_to_rgb,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_PACK_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_unpack,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_SHIFT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_unshift,(png_row_infop row_info,
-    png_bytep row, png_const_color_8p sig_bits),PNG_EMPTY);
-#endif
-
-#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_scale_16_to_8,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_chop,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_QUANTIZE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_quantize,(png_row_infop row_info,
-    png_bytep row, png_const_bytep palette_lookup,
-    png_const_bytep quantize_lookup),PNG_EMPTY);
-
-#  ifdef PNG_CORRECT_PALETTE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_correct_palette,(png_structrp png_ptr,
-    png_colorp palette, int num_palette),PNG_EMPTY);
-#  endif
-#endif
-
-#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_PACK_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_pack,(png_row_infop row_info,
-   png_bytep row, png_uint_32 bit_depth),PNG_EMPTY);
-#endif
-
-#ifdef PNG_WRITE_SHIFT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_shift,(png_row_infop row_info,
-    png_bytep row, png_const_color_8p bit_depth),PNG_EMPTY);
-#endif
-
-#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
-    defined(PNG_READ_ALPHA_MODE_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_compose,(png_row_infop row_info,
-    png_bytep row, png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_gamma,(png_row_infop row_info,
-    png_bytep row, png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_encode_alpha,(png_row_infop row_info,
-   png_bytep row, png_structrp png_ptr),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_EXPAND_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_expand_palette,(png_row_infop row_info,
-    png_bytep row, png_const_colorp palette, png_const_bytep trans,
-    int num_trans),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_do_expand,(png_row_infop row_info,
-    png_bytep row, png_const_color_16p trans_color),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_EXPAND_16_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_expand_16,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-/* The following decodes the appropriate chunks, and does error correction,
- * then calls the appropriate callback for the chunk if it is valid.
- */
-
-/* Decode the IHDR chunk */
-PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-
-#ifdef PNG_READ_bKGD_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_cHRM_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_gAMA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_hIST_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_iCCP_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif /* PNG_READ_iCCP_SUPPORTED */
-
-#ifdef PNG_READ_iTXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_oFFs_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_pCAL_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_pHYs_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_sBIT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_sCAL_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_sPLT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif /* PNG_READ_sPLT_SUPPORTED */
-
-#ifdef PNG_READ_sRGB_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_tEXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_tIME_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_tRNS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_zTXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-#endif
-
-PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr,
-    png_uint_32 chunk_name),PNG_EMPTY);
-
-#ifdef PNG_READ_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
-   /* This is the function that gets called for unknown chunks.  The 'keep'
-    * argument is either non-zero for a known chunk that has been set to be
-    * handled as unknown or zero for an unknown chunk.  By default the function
-    * just skips the chunk or errors out if it is critical.
-    */
-
-#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
-#ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
-PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
-    (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
-   /* Exactly as the API png_handle_as_unknown() except that the argument is a
-    * 32-bit chunk name, not a string.
-    */
-#endif
-#endif /* PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */
-#endif /* PNG_READ_SUPPORTED */
-
-/* Handle the transformations for reading and writing */
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
-   png_row_infop row_info),PNG_EMPTY);
-#endif
-#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
-   png_row_infop row_info),PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_TRANSFORMS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
-    PNG_EMPTY);
-#endif
-
-#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_crc_skip,(png_structrp png_ptr,
-    png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_crc_finish,(png_structrp png_ptr),
-    PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
-    PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
-    png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
-    png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
-    PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
-   png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
-   png_inforp info_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
-   png_inforp info_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
-     png_bytep row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
-    PNG_EMPTY);
-#  ifdef PNG_READ_tEXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-#  endif
-#  ifdef PNG_READ_zTXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-#  endif
-#  ifdef PNG_READ_iTXt_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
-    png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
-    png_inforp info_ptr),PNG_EMPTY);
-#  endif
-
-#endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
-
-#ifdef PNG_MNG_FEATURES_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_do_read_intrapixel,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_do_write_intrapixel,(png_row_infop row_info,
-    png_bytep row),PNG_EMPTY);
-#endif
-
-/* Added at libpng version 1.6.0 */
-#ifdef PNG_GAMMA_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
-    png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
-   /* Set the colorspace gamma with a value provided by the application or by
-    * the gAMA chunk on read.  The value will override anything set by an ICC
-    * profile.
-    */
-
-PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
-    png_inforp info_ptr), PNG_EMPTY);
-    /* Synchronize the info 'valid' flags with the colorspace */
-
-PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
-    png_inforp info_ptr), PNG_EMPTY);
-    /* Copy the png_struct colorspace to the info_struct and call the above to
-     * synchronize the flags.  Checks for NULL info_ptr and does nothing.
-     */
-#endif
-
-/* Added at libpng version 1.4.0 */
-#ifdef PNG_COLORSPACE_SUPPORTED
-/* These internal functions are for maintaining the colorspace structure within
- * a png_info or png_struct (or, indeed, both).
- */
-PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
-   (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
-    int preferred), PNG_EMPTY);
-
-PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
-   (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
-    int preferred), PNG_EMPTY);
-
-#ifdef PNG_sRGB_SUPPORTED
-PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
-   png_colorspacerp colorspace, int intent), PNG_EMPTY);
-   /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
-    * flags to write them, if it returns false there was a problem and an error
-    * message has already been output (but the colorspace may still need to be
-    * synced to record the invalid flag).
-    */
-#endif /* sRGB */
-
-#ifdef PNG_iCCP_SUPPORTED
-PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
-   png_colorspacerp colorspace, png_const_charp name,
-   png_uint_32 profile_length, png_const_bytep profile, int color_type),
-   PNG_EMPTY);
-   /* The 'name' is used for information only */
-
-/* Routines for checking parts of an ICC profile. */
-PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
-   png_colorspacerp colorspace, png_const_charp name,
-   png_uint_32 profile_length), PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
-   png_colorspacerp colorspace, png_const_charp name,
-   png_uint_32 profile_length,
-   png_const_bytep profile /* first 132 bytes only */, int color_type),
-   PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
-   png_colorspacerp colorspace, png_const_charp name,
-   png_uint_32 profile_length,
-   png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
-#ifdef PNG_sRGB_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
-   png_const_structrp png_ptr, png_colorspacerp colorspace,
-   png_const_bytep profile, uLong adler), PNG_EMPTY);
-   /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
-    * be zero to indicate that it is not available.  It is used, if provided,
-    * as a fast check on the profile when checking to see if it is sRGB.
-    */
-#endif
-#endif /* iCCP */
-
-#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
-   (png_structrp png_ptr), PNG_EMPTY);
-   /* Set the rgb_to_gray coefficients from the colorspace Y values */
-#endif /* READ_RGB_TO_GRAY */
-#endif /* COLORSPACE */
-
-/* Added at libpng version 1.4.0 */
-PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
-    png_uint_32 width, png_uint_32 height, int bit_depth,
-    int color_type, int interlace_type, int compression_type,
-    int filter_type),PNG_EMPTY);
-
-/* Added at libpng version 1.5.10 */
-#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
-    defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
-   (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
-#endif
-
-#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
-PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
-   png_const_charp name),PNG_NORETURN);
-#endif
-
-/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
- * the end.  Always leaves the buffer nul terminated.  Never errors out (and
- * there is no error code.)
- */
-PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
-   size_t pos, png_const_charp string),PNG_EMPTY);
-
-/* Various internal functions to handle formatted warning messages, currently
- * only implemented for warnings.
- */
-#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
-/* Utility to dump an unsigned value into a buffer, given a start pointer and
- * and end pointer (which should point just *beyond* the end of the buffer!)
- * Returns the pointer to the start of the formatted string.  This utility only
- * does unsigned values.
- */
-PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
-   png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
-
-/* Convenience macro that takes an array: */
-#define PNG_FORMAT_NUMBER(buffer,format,number) \
-   png_format_number(buffer, buffer + (sizeof buffer), format, number)
-
-/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
-#define PNG_NUMBER_BUFFER_SIZE 24
-
-/* These are the integer formats currently supported, the name is formed from
- * the standard printf(3) format string.
- */
-#define PNG_NUMBER_FORMAT_u     1 /* chose unsigned API! */
-#define PNG_NUMBER_FORMAT_02u   2
-#define PNG_NUMBER_FORMAT_d     1 /* chose signed API! */
-#define PNG_NUMBER_FORMAT_02d   2
-#define PNG_NUMBER_FORMAT_x     3
-#define PNG_NUMBER_FORMAT_02x   4
-#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
-#endif
-
-#ifdef PNG_WARNINGS_SUPPORTED
-/* New defines and members adding in libpng-1.5.4 */
-#  define PNG_WARNING_PARAMETER_SIZE 32
-#  define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
-
-/* An l-value of this type has to be passed to the APIs below to cache the
- * values of the parameters to a formatted warning message.
- */
-typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
-   PNG_WARNING_PARAMETER_SIZE];
-
-PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
-   int number, png_const_charp string),PNG_EMPTY);
-   /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
-    * including the trailing '\0'.
-    */
-PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
-   (png_warning_parameters p, int number, int format, png_alloc_size_t value),
-   PNG_EMPTY);
-   /* Use png_alloc_size_t because it is an unsigned type as big as any we
-    * need to output.  Use the following for a signed value.
-    */
-PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
-   (png_warning_parameters p, int number, int format, png_int_32 value),
-   PNG_EMPTY);
-
-PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
-   png_warning_parameters p, png_const_charp message),PNG_EMPTY);
-   /* 'message' follows the X/Open approach of using @1, @2 to insert
-    * parameters previously supplied using the above functions.  Errors in
-    * specifying the parameters will simply result in garbage substitutions.
-    */
-#endif
-
-#ifdef PNG_BENIGN_ERRORS_SUPPORTED
-/* Application errors (new in 1.6); use these functions (declared below) for
- * errors in the parameters or order of API function calls on read.  The
- * 'warning' should be used for an error that can be handled completely; the
- * 'error' for one which can be handled safely but which may lose application
- * information or settings.
- *
- * By default these both result in a png_error call prior to release, while in a
- * released version the 'warning' is just a warning.  However if the application
- * explicitly disables benign errors (explicitly permitting the code to lose
- * information) they both turn into warnings.
- *
- * If benign errors aren't supported they end up as the corresponding base call
- * (png_warning or png_error.)
- */
-PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
-   png_const_charp message),PNG_EMPTY);
-   /* The application provided invalid parameters to an API function or called
-    * an API function at the wrong time, libpng can completely recover.
-    */
-
-PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
-   png_const_charp message),PNG_EMPTY);
-   /* As above but libpng will ignore the call, or attempt some other partial
-    * recovery from the error.
-    */
-#else
-#  define png_app_warning(pp,s) png_warning(pp,s)
-#  define png_app_error(pp,s) png_error(pp,s)
-#endif
-
-PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
-   png_const_charp message, int error),PNG_EMPTY);
-   /* Report a recoverable issue in chunk data.  On read this is used to report
-    * a problem found while reading a particular chunk and the
-    * png_chunk_benign_error or png_chunk_warning function is used as
-    * appropriate.  On write this is used to report an error that comes from
-    * data set via an application call to a png_set_ API and png_app_error or
-    * png_app_warning is used as appropriate.
-    *
-    * The 'error' parameter must have one of the following values:
-    */
-#define PNG_CHUNK_WARNING     0 /* never an error */
-#define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
-#define PNG_CHUNK_ERROR       2 /* always an error */
-
-/* ASCII to FP interfaces, currently only implemented if sCAL
- * support is required.
- */
-#if defined(PNG_sCAL_SUPPORTED)
-/* MAX_DIGITS is actually the maximum number of characters in an sCAL
- * width or height, derived from the precision (number of significant
- * digits - a build time settable option) and assumptions about the
- * maximum ridiculous exponent.
- */
-#define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
-
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
-   png_charp ascii, png_size_t size, double fp, unsigned int precision),
-   PNG_EMPTY);
-#endif /* FLOATING_POINT */
-
-#ifdef PNG_FIXED_POINT_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
-   png_charp ascii, png_size_t size, png_fixed_point fp),PNG_EMPTY);
-#endif /* FIXED_POINT */
-#endif /* sCAL */
-
-#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
-/* An internal API to validate the format of a floating point number.
- * The result is the index of the next character.  If the number is
- * not valid it will be the index of a character in the supposed number.
- *
- * The format of a number is defined in the PNG extensions specification
- * and this API is strictly conformant to that spec, not anyone elses!
- *
- * The format as a regular expression is:
- *
- * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
- *
- * or:
- *
- * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
- *
- * The complexity is that either integer or fraction must be present and the
- * fraction is permitted to have no digits only if the integer is present.
- *
- * NOTE: The dangling E problem.
- *   There is a PNG valid floating point number in the following:
- *
- *       PNG floating point numbers are not greedy.
- *
- *   Working this out requires *TWO* character lookahead (because of the
- *   sign), the parser does not do this - it will fail at the 'r' - this
- *   doesn't matter for PNG sCAL chunk values, but it requires more care
- *   if the value were ever to be embedded in something more complex.  Use
- *   ANSI-C strtod if you need the lookahead.
- */
-/* State table for the parser. */
-#define PNG_FP_INTEGER    0  /* before or in integer */
-#define PNG_FP_FRACTION   1  /* before or in fraction */
-#define PNG_FP_EXPONENT   2  /* before or in exponent */
-#define PNG_FP_STATE      3  /* mask for the above */
-#define PNG_FP_SAW_SIGN   4  /* Saw +/- in current state */
-#define PNG_FP_SAW_DIGIT  8  /* Saw a digit in current state */
-#define PNG_FP_SAW_DOT   16  /* Saw a dot in current state */
-#define PNG_FP_SAW_E     32  /* Saw an E (or e) in current state */
-#define PNG_FP_SAW_ANY   60  /* Saw any of the above 4 */
-
-/* These three values don't affect the parser.  They are set but not used.
- */
-#define PNG_FP_WAS_VALID 64  /* Preceding substring is a valid fp number */
-#define PNG_FP_NEGATIVE 128  /* A negative number, including "-0" */
-#define PNG_FP_NONZERO  256  /* A non-zero value */
-#define PNG_FP_STICKY   448  /* The above three flags */
-
-/* This is available for the caller to store in 'state' if required.  Do not
- * call the parser after setting it (the parser sometimes clears it.)
- */
-#define PNG_FP_INVALID  512  /* Available for callers as a distinct value */
-
-/* Result codes for the parser (boolean - true meants ok, false means
- * not ok yet.)
- */
-#define PNG_FP_MAYBE      0  /* The number may be valid in the future */
-#define PNG_FP_OK         1  /* The number is valid */
-
-/* Tests on the sticky non-zero and negative flags.  To pass these checks
- * the state must also indicate that the whole number is valid - this is
- * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
- * is equivalent to PNG_FP_OK above.)
- */
-#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
-   /* NZ_MASK: the string is valid and a non-zero negative value */
-#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
-   /* Z MASK: the string is valid and a non-zero value. */
-   /* PNG_FP_SAW_DIGIT: the string is valid. */
-#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
-#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
-#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
-
-/* The actual parser.  This can be called repeatedly. It updates
- * the index into the string and the state variable (which must
- * be initialized to 0).  It returns a result code, as above.  There
- * is no point calling the parser any more if it fails to advance to
- * the end of the string - it is stuck on an invalid character (or
- * terminated by '\0').
- *
- * Note that the pointer will consume an E or even an E+ and then leave
- * a 'maybe' state even though a preceding integer.fraction is valid.
- * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
- * a valid number.  It's possible to recover from this by calling
- * the parser again (from the start, with state 0) but with a string
- * that omits the last character (i.e. set the size to the index of
- * the problem character.)  This has not been tested within libpng.
- */
-PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
-   png_size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
-
-/* This is the same but it checks a complete string and returns true
- * only if it just contains a floating point number.  As of 1.5.4 this
- * function also returns the state at the end of parsing the number if
- * it was valid (otherwise it returns 0.)  This can be used for testing
- * for negative or zero values using the sticky flag.
- */
-PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
-   png_size_t size),PNG_EMPTY);
-#endif /* pCAL || sCAL */
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
-    defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
-/* Added at libpng version 1.5.0 */
-/* This is a utility to provide a*times/div (rounded) and indicate
- * if there is an overflow.  The result is a boolean - false (0)
- * for overflow, true (1) if no overflow, in which case *res
- * holds the result.
- */
-PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
-   png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
-#endif
-
-#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
-/* Same deal, but issue a warning on overflow and return 0. */
-PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
-   (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
-   png_int_32 divided_by),PNG_EMPTY);
-#endif
-
-#ifdef PNG_GAMMA_SUPPORTED
-/* Calculate a reciprocal - used for gamma values.  This returns
- * 0 if the argument is 0 in order to maintain an undefined value;
- * there are no warnings.
- */
-PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
-   PNG_EMPTY);
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* The same but gives a reciprocal of the product of two fixed point
- * values.  Accuracy is suitable for gamma calculations but this is
- * not exact - use png_muldiv for that.  Only required at present on read.
- */
-PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
-   png_fixed_point b),PNG_EMPTY);
-#endif
-
-/* Return true if the gamma value is significantly different from 1.0 */
-PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
-   PNG_EMPTY);
-#endif
-
-#ifdef PNG_READ_GAMMA_SUPPORTED
-/* Internal fixed point gamma correction.  These APIs are called as
- * required to convert single values - they don't need to be fast,
- * they are not used when processing image pixel values.
- *
- * While the input is an 'unsigned' value it must actually be the
- * correct bit value - 0..255 or 0..65535 as required.
- */
-PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
-   unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
-   png_fixed_point gamma_value),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
-   png_fixed_point gamma_value),PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
-   PNG_EMPTY);
-PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
-   int bit_depth),PNG_EMPTY);
-#endif
-
-/* SIMPLIFIED READ/WRITE SUPPORT */
-#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
-   defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
-/* The internal structure that png_image::opaque points to. */
-typedef struct png_control
-{
-   png_structp png_ptr;
-   png_infop   info_ptr;
-   png_voidp   error_buf;           /* Always a jmp_buf at present. */
-
-   png_const_bytep memory;          /* Memory buffer. */
-   png_size_t      size;            /* Size of the memory buffer. */
-
-   unsigned int for_write       :1; /* Otherwise it is a read structure */
-   unsigned int owned_file      :1; /* We own the file in io_ptr */
-} png_control;
-
-/* Return the pointer to the jmp_buf from a png_control: necessary because C
- * does not reveal the type of the elements of jmp_buf.
- */
-#ifdef __cplusplus
-#  define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
-#else
-#  define png_control_jmp_buf(pc) ((pc)->error_buf)
-#endif
-
-/* Utility to safely execute a piece of libpng code catching and logging any
- * errors that might occur.  Returns true on success, false on failure (either
- * of the function or as a result of a png_error.)
- */
-PNG_INTERNAL_FUNCTION(void,png_safe_error,(png_structp png_ptr,
-   png_const_charp error_message),PNG_NORETURN);
-
-#ifdef PNG_WARNINGS_SUPPORTED
-PNG_INTERNAL_FUNCTION(void,png_safe_warning,(png_structp png_ptr,
-   png_const_charp warning_message),PNG_EMPTY);
-#else
-#  define png_safe_warning 0/*dummy argument*/
-#endif
-
-PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
-   int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
-
-/* Utility to log an error; this also cleans up the png_image; the function
- * always returns 0 (false).
- */
-PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
-   png_const_charp error_message),PNG_EMPTY);
-
-#ifndef PNG_SIMPLIFIED_READ_SUPPORTED
-/* png_image_free is used by the write code but not exported */
-PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
-#endif /* !SIMPLIFIED_READ */
-
-#endif /* SIMPLIFIED READ/WRITE */
-
-/* These are initialization functions for hardware specific PNG filter
- * optimizations; list these here then select the appropriate one at compile
- * time using the macro PNG_FILTER_OPTIMIZATIONS.  If the macro is not defined
- * the generic code is used.
- */
-#ifdef PNG_FILTER_OPTIMIZATIONS
-PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
-   unsigned int bpp), PNG_EMPTY);
-   /* Just declare the optimization that will be used */
-#else
-   /* List *all* the possible optimizations here - this branch is required if
-    * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
-    * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
-    */
-PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
-   (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
-#endif
-
-/* Maintainer: Put new private prototypes here ^ */
-
-#include "pngdebug.h"
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* PNG_VERSION_INFO_ONLY */
-#endif /* PNGPRIV_H */