/* pngpriv.h - private declarations for use inside libpng
*
* Copyright (c) 2018-2025 Cosmin Truta
* Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
* Copyright (c) 1996-1997 Andreas Dilger
* 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
*/
/* 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.
*/
/* pngpriv.h must be included first in each translation unit inside libpng.
* On the other hand, it must not be included at all, directly or indirectly,
* by any application code that uses the libpng API.
*/
#ifndef PNGPRIV_H
# define PNGPRIV_H
#else
# error Duplicate inclusion of pngpriv.h; please check the libpng source files
#endif
#if defined(PNG_H) ||
defined(PNGCONF_H) ||
defined(PNGLCONF_H)
# error This file must
not be included by applications; please include <png.h>
#endif
/* 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.)
*/
#ifndef _POSIX_SOURCE
# define _POSIX_SOURCE
1 /* Just the POSIX 1003.1 and C89 APIs */
#endif
#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.
*/
#include "pnglibconf.h"
/* 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.
*
* NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
* can only be turned on automatically if that is supported too. If
* PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
* to compile with an appropriate #error if ALIGNED_MEMORY has been turned
* off.
*
* Note that gcc-4.9 defines __ARM_NEON instead of the deprecated
* __ARM_NEON__, so we check both variants.
*
* To disable ARM_NEON optimizations entirely, and skip compiling the
* associated assembler code, pass --enable-arm-neon=no to configure
* or put -DPNG_ARM_NEON_OPT=0 in CPPFLAGS.
*/
# if (
defined(__ARM_NEON__) ||
defined(__ARM_NEON)) && \
defined(PNG_ALIGNED_MEMORY_SUPPORTED)
# define PNG_ARM_NEON_OPT
2
# else
# define PNG_ARM_NEON_OPT
0
# endif
#endif
#ifndef PNG_RISCV_RVV_OPT
/* RISCV_RVV optimizations are being controlled by the compiler settings,
* typically the target compiler will define __riscv but the rvv extension
* availability has to be explicitly stated. This is why if no
* PNG_RISCV_RVV_OPT was defined then a runtime check will be executed.
*
* To enable RISCV_RVV optimizations unconditionally, and compile the
* associated code, pass --enable-riscv-rvv=yes or --enable-riscv-rvv=on
* to configure or put -DPNG_RISCV_RVV_OPT=2 in CPPFLAGS.
*/
# define PNG_RISCV_RVV_OPT
0
#endif
#if PNG_ARM_NEON_OPT >
0
/* NEON optimizations are to be at least considered by libpng, so enable the
* callbacks to do this.
*/
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
# ifndef PNG_ARM_NEON_IMPLEMENTATION
/* Use the intrinsics code by default. */
# define PNG_ARM_NEON_IMPLEMENTATION
1
# endif
#else /* PNG_ARM_NEON_OPT == 0 */
# define PNG_ARM_NEON_IMPLEMENTATION
0
#endif /* PNG_ARM_NEON_OPT > 0 */
#ifndef PNG_MIPS_MSA_OPT
# if defined(__mips_msa) && (__mips_isa_rev >=
5) && \
defined(PNG_ALIGNED_MEMORY_SUPPORTED)
# define PNG_MIPS_MSA_OPT
2
# else
# define PNG_MIPS_MSA_OPT
0
# endif
#endif
#ifndef PNG_MIPS_MMI_OPT
# ifdef PNG_MIPS_MMI
# if defined(__mips_loongson_mmi) && (_MIPS_SIM == _ABI64) && \
defined(PNG_ALIGNED_MEMORY_SUPPORTED)
# define PNG_MIPS_MMI_OPT
1
# else
# define PNG_MIPS_MMI_OPT
0
# endif
# else
# define PNG_MIPS_MMI_OPT
0
# endif
#endif
#ifndef PNG_POWERPC_VSX_OPT
# if defined(__PPC64__) &&
defined(__ALTIVEC__) &&
defined(__VSX__)
# define PNG_POWERPC_VSX_OPT
2
# else
# define PNG_POWERPC_VSX_OPT
0
# endif
#endif
#ifndef PNG_LOONGARCH_LSX_OPT
# if defined(__loongarch_sx)
# define PNG_LOONGARCH_LSX_OPT
1
# else
# define PNG_LOONGARCH_LSX_OPT
0
# endif
#endif
#ifndef PNG_INTEL_SSE_OPT
# ifdef PNG_INTEL_SSE
/* Only check for SSE if the build configuration has been modified to
* enable SSE optimizations. This means that these optimizations will
* be off by default. See contrib/intel for more details.
*/
# if defined(__SSE4_1__) ||
defined(__AVX__) ||
defined(__SSSE3__) || \
defined(__SSE2__) ||
defined(_M_X64) ||
defined(_M_AMD64) || \
(
defined(_M_IX86_FP) && _M_IX86_FP >=
2)
# define PNG_INTEL_SSE_OPT
1
# else
# define PNG_INTEL_SSE_OPT
0
# endif
# else
# define PNG_INTEL_SSE_OPT
0
# endif
#endif
#if PNG_INTEL_SSE_OPT >
0
# ifndef PNG_INTEL_SSE_IMPLEMENTATION
# if defined(__SSE4_1__) ||
defined(__AVX__)
/* We are not actually using AVX, but checking for AVX is the best
way we can detect SSE4.1 and SSSE3 on MSVC.
*/
# define PNG_INTEL_SSE_IMPLEMENTATION
3
# elif
defined(__SSSE3__)
# define PNG_INTEL_SSE_IMPLEMENTATION
2
# elif
defined(__SSE2__) ||
defined(_M_X64) ||
defined(_M_AMD64) || \
(
defined(_M_IX86_FP) && _M_IX86_FP >=
2)
# define PNG_INTEL_SSE_IMPLEMENTATION
1
# else
# define PNG_INTEL_SSE_IMPLEMENTATION
0
# endif
# endif
# if PNG_INTEL_SSE_IMPLEMENTATION >
0
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
# endif
#else
# define PNG_INTEL_SSE_IMPLEMENTATION
0
#endif
#if PNG_MIPS_MSA_OPT >
0
# ifndef PNG_MIPS_MSA_IMPLEMENTATION
# if defined(__mips_msa)
# if defined(__clang__)
# elif
defined(__GNUC__)
# if __GNUC__ <
4 || (__GNUC__ ==
4 && __GNUC_MINOR__ <
7)
# define PNG_MIPS_MSA_IMPLEMENTATION
2
# endif
/* no GNUC support */
# endif
/* __GNUC__ */
# else /* !defined __mips_msa */
# define PNG_MIPS_MSA_IMPLEMENTATION
2
# endif
/* __mips_msa */
# endif
/* !PNG_MIPS_MSA_IMPLEMENTATION */
# ifndef PNG_MIPS_MSA_IMPLEMENTATION
# define PNG_MIPS_MSA_IMPLEMENTATION
1
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_mips
# endif
#else
# define PNG_MIPS_MSA_IMPLEMENTATION
0
#endif /* PNG_MIPS_MSA_OPT > 0 */
#if PNG_MIPS_MMI_OPT >
0
# ifndef PNG_MIPS_MMI_IMPLEMENTATION
# if defined(__mips_loongson_mmi) && (_MIPS_SIM == _ABI64)
# define PNG_MIPS_MMI_IMPLEMENTATION
2
# else /* !defined __mips_loongson_mmi || _MIPS_SIM != _ABI64 */
# define PNG_MIPS_MMI_IMPLEMENTATION
0
# endif
/* __mips_loongson_mmi && _MIPS_SIM == _ABI64 */
# endif
/* !PNG_MIPS_MMI_IMPLEMENTATION */
# if PNG_MIPS_MMI_IMPLEMENTATION >
0
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_mips
# endif
#else
# define PNG_MIPS_MMI_IMPLEMENTATION
0
#endif /* PNG_MIPS_MMI_OPT > 0 */
#if PNG_POWERPC_VSX_OPT >
0
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
# define PNG_POWERPC_VSX_IMPLEMENTATION
1
#else
# define PNG_POWERPC_VSX_IMPLEMENTATION
0
#endif
#if PNG_LOONGARCH_LSX_OPT >
0
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_lsx
# define PNG_LOONGARCH_LSX_IMPLEMENTATION
1
#else
# define PNG_LOONGARCH_LSX_IMPLEMENTATION
0
#endif
#if PNG_RISCV_RVV_OPT >
0 && __riscv_v >=
1000000
# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_rvv
# ifndef PNG_RISCV_RVV_IMPLEMENTATION
/* Use the intrinsics code by default. */
# define PNG_RISCV_RVV_IMPLEMENTATION
1
# endif
#else
# define PNG_RISCV_RVV_IMPLEMENTATION
0
#endif /* PNG_RISCV_RVV_OPT > 0 && __riscv_v >= 1000000 */
/* 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) PNG_LINKAGE_DATA type name array
#endif
#ifndef PNG_INTERNAL_FUNCTION
# define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
PNG_LINKAGE_FUNCTION PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
#endif
#ifndef PNG_INTERNAL_CALLBACK
# define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
PNG_LINKAGE_CALLBACK PNG_FUNCTION(type, (PNGCBAPI 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
/* This is a global switch to set the compilation for an installed system
* (a release build). It can be set for testing debug builds to ensure that
* they will compile when the build type is switched to RC or STABLE, the
* default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS
* with either:
*
* -DPNG_RELEASE_BUILD Turns on the release compile path
* -DPNG_RELEASE_BUILD=0 Turns it off
* or in your pngusr.h with
* #define PNG_RELEASE_BUILD=1 Turns on the release compile path
* #define PNG_RELEASE_BUILD=0 Turns it off
*/
#ifndef PNG_RELEASE_BUILD
# define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC)
#endif
/* SECURITY and SAFETY:
*
* libpng is built with support for internal limits on image dimensions and
* memory usage. These are documented in scripts/pnglibconf.dfa of the
* source and recorded in the machine generated header file pnglibconf.h.
*/
/* 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_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_fixed_error(s1,s2) png_err(s1)
#endif
/* 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.
*/
/* 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)(
void*)(
const void*)(value))
# define png_aligncast(type, value) ((
void*)(value))
# define png_aligncastconst(type, value) ((
const void*)(value))
#endif /* __cplusplus */
#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>
# include <math.h>
# 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(__WIN32__) ||
defined(__NT__)
# include <windows.h>
#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.
*/
/* Platform-independent functions */
#ifndef PNG_ABORT
# define PNG_ABORT() abort()
#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 a multiple of 2. */
#ifdef png_alignof
# define png_isaligned(ptr, type) \
(((type)(size_t)((
const void*)(ptr)) & (type)(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 0x01U (defined in png.h) */
/* #define PNG_HAVE_PLTE 0x02U (defined in png.h) */
#define PNG_HAVE_IDAT
0x04U
/* #define PNG_AFTER_IDAT 0x08U (defined in png.h) */
#define PNG_HAVE_IEND
0x10U
/* 0x20U (unused) */
/* 0x40U (unused) */
/* 0x80U (unused) */
#define PNG_HAVE_CHUNK_HEADER
0x100U
#define PNG_WROTE_tIME
0x200U
#define PNG_WROTE_INFO_BEFORE_PLTE
0x400U
#define PNG_BACKGROUND_IS_GRAY
0x800U
#define PNG_HAVE_PNG_SIGNATURE
0x1000U
#define PNG_HAVE_CHUNK_AFTER_IDAT
0x2000U
/* Have another chunk after IDAT */
#define PNG_WROTE_eXIf
0x4000U
#define PNG_IS_READ_STRUCT
0x8000U
/* Else is a write struct */
#ifdef PNG_APNG_SUPPORTED
#define PNG_HAVE_acTL
0x10000U
#define PNG_HAVE_fcTL
0x20000U
#endif
/* Flags for the transformations the PNG library does on the image data */
#define PNG_BGR
0x0001U
#define PNG_INTERLACE
0x0002U
#define PNG_PACK
0x0004U
#define PNG_SHIFT
0x0008U
#define PNG_SWAP_BYTES
0x0010U
#define PNG_INVERT_MONO
0x0020U
#define PNG_QUANTIZE
0x0040U
#define PNG_COMPOSE
0x0080U
/* Was PNG_BACKGROUND */
#define PNG_BACKGROUND_EXPAND
0x0100U
#define PNG_EXPAND_16
0x0200U
/* Added to libpng 1.5.2 */
#define PNG_16_TO_8
0x0400U
/* Becomes 'chop' in 1.5.4 */
#define PNG_RGBA
0x0800U
#define PNG_EXPAND
0x1000U
#define PNG_GAMMA
0x2000U
#define PNG_GRAY_TO_RGB
0x4000U
#define PNG_FILLER
0x8000U
#define PNG_PACKSWAP
0x10000U
#define PNG_SWAP_ALPHA
0x20000U
#define PNG_STRIP_ALPHA
0x40000U
#define PNG_INVERT_ALPHA
0x80000U
#define PNG_USER_TRANSFORM
0x100000U
#define PNG_RGB_TO_GRAY_ERR
0x200000U
#define PNG_RGB_TO_GRAY_WARN
0x400000U
#define PNG_RGB_TO_GRAY
0x600000U
/* two bits, RGB_TO_GRAY_ERR|WARN */
#define PNG_ENCODE_ALPHA
0x800000U
/* Added to libpng-1.5.4 */
#define PNG_ADD_ALPHA
0x1000000U
/* Added to libpng-1.2.7 */
#define PNG_EXPAND_tRNS
0x2000000U
/* Added to libpng-1.2.9 */
#define PNG_SCALE_16_TO_8
0x4000000U
/* Added to libpng-1.5.4 */
/* 0x8000000U unused */
/* 0x10000000U unused */
/* 0x20000000U unused */
/* 0x40000000U unused */
/* Flags for png_create_struct */
#define PNG_STRUCT_PNG
0x0001U
#define PNG_STRUCT_INFO
0x0002U
/* Flags for the png_ptr->flags rather than declaring a byte for each one */
#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY
0x0001U
#define PNG_FLAG_ZSTREAM_INITIALIZED
0x0002U
/* Added to libpng-1.6.0 */
/* 0x0004U unused */
#define PNG_FLAG_ZSTREAM_ENDED
0x0008U
/* Added to libpng-1.6.0 */
/* 0x0010U unused */
/* 0x0020U unused */
#define PNG_FLAG_ROW_INIT
0x0040U
#define PNG_FLAG_FILLER_AFTER
0x0080U
#define PNG_FLAG_CRC_ANCILLARY_USE
0x0100U
#define PNG_FLAG_CRC_ANCILLARY_NOWARN
0x0200U
#define PNG_FLAG_CRC_CRITICAL_USE
0x0400U
#define PNG_FLAG_CRC_CRITICAL_IGNORE
0x0800U
/* PNG_FLAG_ASSUME_sRGB unused 0x1000U * Added to libpng-1.5.4 */
#define PNG_FLAG_OPTIMIZE_ALPHA
0x2000U
/* Added to libpng-1.5.4 */
#define PNG_FLAG_DETECT_UNINITIALIZED
0x4000U
/* Added to libpng-1.5.4 */
/* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000U */
/* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000U */
#define PNG_FLAG_LIBRARY_MISMATCH
0x20000U
/* 0x40000U unused */
#define PNG_FLAG_STRIP_ERROR_TEXT
0x80000U
#define PNG_FLAG_BENIGN_ERRORS_WARN
0x100000U
/* Added to libpng-1.4.0 */
#define PNG_FLAG_APP_WARNINGS_WARN
0x200000U
/* Added to libpng-1.6.0 */
#define PNG_FLAG_APP_ERRORS_WARN
0x400000U
/* Added to libpng-1.6.0 */
/* 0x800000U unused */
/* 0x1000000U unused */
/* 0x2000000U unused */
/* 0x4000000U unused */
/* 0x8000000U unused */
/* 0x10000000U unused */
/* 0x20000000U unused */
/* 0x40000000U 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 ? \
((size_t)(width) * (((size_t)(pixel_bits)) >>
3)) : \
(( ((size_t)(width) * ((size_t)(pixel_bits))) +
7) >>
3) )
/* This returns the number of trailing bits in the last byte of a row, 0 if the
* last byte is completely full of pixels. It is, in principle, (pixel_bits x
* width) % 8, but that would overflow for large 'width'. The second macro is
* the same except that it returns the number of unused bits in the last byte;
* (8-TRAILBITS), but 0 when TRAILBITS is 0.
*
* NOTE: these macros are intended to be self-evidently correct and never
* overflow on the assumption that pixel_bits is in the range 0..255. The
* arguments are evaluated only once and they can be signed (e.g. as a result of
* the integral promotions). The result of the expression always has type
* (png_uint_32), however the compiler always knows it is in the range 0..7.
*/
#define PNG_TRAILBITS(pixel_bits, width) \
(((pixel_bits) * ((width) % (png_uint_32)
8)) %
8)
#define PNG_PADBITS(pixel_bits, width) \
((
8 - PNG_TRAILBITS(pixel_bits, width)) %
8)
/* 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))
#define png_fixed_ITU(png_ptr, fp, s) ((fp) <=
214748 && (fp) >=
0 ?\
((png_uint_32)(
10000 * (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.
*
* 1.6.47: PNG_32b was made into a preprocessor evaluable macro by replacing the
* static_cast with a promoting binary operation using a guaranteed 32-bit
* (minimum) unsigned value.
*/
#define PNG_32b(b,s) (((
0xFFFFFFFFU)&(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))
/* Chunk name validation. When using these macros all the arguments should be
* constants, otherwise code bloat may well occur. The macros are provided
* primarily for use in #if checks.
*
* PNG_32to8 produces a byte value with the right shift; used to extract the
* byte value from a chunk name.
*/
#define PNG_32to8(cn,s) (((cn) >> (s)) &
0xffU)
#define PNG_CN_VALID_UPPER(b) ((b) >=
65 && (b) <=
90)
/* upper-case ASCII */
#define PNG_CN_VALID_ASCII(b) PNG_CN_VALID_UPPER((b) & ~
32U)
#define PNG_CHUNK_NAME_VALID(cn) (\
PNG_CN_VALID_ASCII(PNG_32to8(cn,
24)) &&
/* critical, !ancillary */\
PNG_CN_VALID_ASCII(PNG_32to8(cn,
16)) &&
/* public, !privately defined */\
PNG_CN_VALID_UPPER(PNG_32to8(cn,
8)) &&
/* VALID, !reserved */\
PNG_CN_VALID_ASCII(PNG_32to8(cn,
0))
/* data-dependent, !copy ok */)
/* 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_acTL PNG_U32(
97,
99,
84,
76)
/* PNGv3: APNG */
#define png_bKGD PNG_U32(
98,
75,
71,
68)
#define png_cHRM PNG_U32(
99,
72,
82,
77)
#define png_cICP PNG_U32(
99,
73,
67,
80)
/* PNGv3 */
#define png_cLLI PNG_U32(
99,
76,
76,
73)
/* PNGv3 */
#define png_eXIf PNG_U32(
101,
88,
73,
102)
/* registered July 2017 */
#define png_fcTL PNG_U32(
102,
99,
84,
76)
/* PNGv3: APNG */
#define png_fdAT PNG_U32(
102,
100,
65,
84)
/* PNGv3: APNG */
#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_mDCV PNG_U32(
109,
68,
67,
86)
/* PNGv3 */
#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)
#ifdef PNG_APNG_SUPPORTED
#define png_acTL PNG_U32(
97,
99,
84,
76)
#define png_fcTL PNG_U32(
102,
99,
84,
76)
#define png_fdAT PNG_U32(
102,
100,
65,
84)
/* For png_struct.apng_flags: */
#define PNG_FIRST_FRAME_HIDDEN
0x0001U
#define PNG_APNG_APP
0x0002U
#endif
/* 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) &
0xff), \
((
char*)(s))[
1]=(
char)(((c)>>
16) &
0xff),\
((
char*)(s))[
2]=(
char)(((c)>>
8) &
0xff), \
((
char*)(s))[
3]=(
char)((c &
0xff)))
/* 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))
/* Known chunks. All supported chunks must be listed here. The macro PNG_CHUNK
* contains the four character ASCII name by which the chunk is identified. The
* macro is implemented as required to build tables or switch statements which
* require entries for every known chunk. The macro also contains an index
* value which should be in order (this is checked in png.c).
*
* Notice that "known" does not require "SUPPORTED"; tables should be built in
* such a way that chunks unsupported in a build require no more than the table
* entry (which should be small.) In particular function pointers for
* unsupported chunks should be NULL.
*
* At present these index values are not exported (not part of the public API)
* so can be changed at will. For convenience the names are in lexical sort
* order but with the critical chunks at the start in the order of occurrence in
* a PNG.
*
* PNG_INFO_ values do not exist for every one of these chunk handles; for
* example PNG_INFO_{IDAT,IEND,tEXt,iTXt,zTXt} and possibly other chunks in the
* future.
*/
#define PNG_KNOWN_CHUNKS\
PNG_CHUNK(IHDR,
0)\
PNG_CHUNK(PLTE,
1)\
PNG_CHUNK(IDAT,
2)\
PNG_CHUNK(IEND,
3)\
PNG_CHUNK(acTL,
4)\
PNG_CHUNK(bKGD,
5)\
PNG_CHUNK(cHRM,
6)\
PNG_CHUNK(cICP,
7)\
PNG_CHUNK(cLLI,
8)\
PNG_CHUNK(eXIf,
9)\
PNG_CHUNK(fcTL,
10)\
PNG_CHUNK(fdAT,
11)\
PNG_CHUNK(gAMA,
12)\
PNG_CHUNK(hIST,
13)\
PNG_CHUNK(iCCP,
14)\
PNG_CHUNK(iTXt,
15)\
PNG_CHUNK(mDCV,
16)\
PNG_CHUNK(oFFs,
17)\
PNG_CHUNK(pCAL,
18)\
PNG_CHUNK(pHYs,
19)\
PNG_CHUNK(sBIT,
20)\
PNG_CHUNK(sCAL,
21)\
PNG_CHUNK(sPLT,
22)\
PNG_CHUNK(sRGB,
23)\
PNG_CHUNK(tEXt,
24)\
PNG_CHUNK(tIME,
25)\
PNG_CHUNK(tRNS,
26)\
PNG_CHUNK(zTXt,
27)
/* 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
/* gamma sanity check. libpng cannot implement gamma transforms outside a
* certain limit because of its use of 16-bit fixed point intermediate values.
* Gamma values that are too large or too small will zap the 16-bit values all
* to 0 or 65535 resulting in an obvious 'bad' image.
*
* In libpng 1.6.0 the limits were changed from 0.07..3 to 0.01..100 to
* accommodate the optimal 16-bit gamma of 36 and its reciprocal.
*
* These are png_fixed_point integral values:
*/
#define PNG_LIB_GAMMA_MIN
1000
#define PNG_LIB_GAMMA_MAX
10000000
/* 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 The include path of <zlib.h> is incorrect
/* When pnglibconf.h was built, the copy of zlib.h that it used was not the
* same as the one being used here. Considering how libpng makes decisions
* to use the zlib API based on the zlib version number, the -I options must
* match.
*
* A possible cause of this mismatch is that you passed an -I option in
* CFLAGS, which is unlikely to work. All the preprocessor options, and all
* the -I options in particular, should 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)(
0xff & ((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 /* 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_mDCV_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
#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
!
defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
(
defined(PNG_cLLI_SUPPORTED) ||
defined(PNG_mDCV_SUPPORTED))
PNG_INTERNAL_FUNCTION(png_uint_32, png_fixed_ITU,
(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);
#ifdef PNG_READ_SUPPORTED
/* should only be used on read */
/* Security: read limits on the largest allocations while reading a PNG. This
* avoids very large allocations caused by PNG files with damaged or altered
* chunk 'length' fields.
*/
#ifdef PNG_SET_USER_LIMITS_SUPPORTED
/* run-time limit */
# define png_chunk_max(png_ptr) ((png_ptr)->user_chunk_malloc_max)
#elif PNG_USER_CHUNK_MALLOC_MAX >
0 /* compile-time limit */
# define png_chunk_max(png_ptr) ((
void)png_ptr, PNG_USER_CHUNK_MALLOC_MAX)
#elif (
defined PNG_MAX_MALLOC_64K)
/* legacy system limit */
# define png_chunk_max(png_ptr) ((
void)png_ptr,
65536U)
#else /* modern system limit SIZE_MAX (C99) */
# define png_chunk_max(png_ptr) ((
void)png_ptr, PNG_SIZE_MAX)
#endif
#endif /* READ */
/* 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, 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, size_t length),
PNG_EMPTY);
#endif
PNG_INTERNAL_FUNCTION(
void PNGCBAPI, png_default_write_data,
(png_structp png_ptr, png_bytep data, 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, 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, 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);
/* 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, 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_cICP_SUPPORTED
PNG_INTERNAL_FUNCTION(
void, png_write_cICP,
(png_structrp png_ptr,
png_byte colour_primaries, png_byte transfer_function,
png_byte matrix_coefficients, png_byte video_full_range_flag),
PNG_EMPTY);
#endif
#ifdef PNG_WRITE_cLLI_SUPPORTED
PNG_INTERNAL_FUNCTION(
void, png_write_cLLI_fixed,
(png_structrp png_ptr, png_uint_32 maxCLL, png_uint_32 maxFALL),
PNG_EMPTY);
#endif
#ifdef PNG_WRITE_mDCV_SUPPORTED
PNG_INTERNAL_FUNCTION(
void, png_write_mDCV_fixed,
(png_structrp png_ptr,
png_uint_16 red_x, png_uint_16 red_y,
png_uint_16 green_x, png_uint_16 green_y,
png_uint_16 blue_x, png_uint_16 blue_y,
png_uint_16 white_x, png_uint_16 white_y,
png_uint_32 maxDL, png_uint_32 minDL),
PNG_EMPTY);
#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_eXIf_SUPPORTED
PNG_INTERNAL_FUNCTION(
void, png_write_eXIf,
(png_structrp png_ptr, png_bytep exif,
int num_exif),
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_uint_32 proflen),
PNG_EMPTY);
/* Writes a previously 'set' profile. The profile argument is **not**
* compressed.
*/
#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, 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,
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);
#if PNG_ARM_NEON_OPT >
0
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);
#endif
#if PNG_MIPS_MSA_IMPLEMENTATION ==
1
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_up_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub3_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub4_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg3_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg4_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth3_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth4_msa,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
#endif
#if PNG_MIPS_MMI_IMPLEMENTATION >
0
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_up_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub3_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub4_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg3_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg4_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth3_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth4_mmi,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
#endif
#if PNG_POWERPC_VSX_OPT >
0
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_up_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub3_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub4_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg3_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg4_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth3_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth4_vsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
#endif
#if PNG_INTEL_SSE_IMPLEMENTATION >
0
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub3_sse2,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub4_sse2,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg3_sse2,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg4_sse2,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth3_sse2,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth4_sse2,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
#endif
#if PNG_LOONGARCH_LSX_IMPLEMENTATION ==
1
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_up_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub3_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub4_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg3_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg4_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth3_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth4_lsx,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
#endif
#if PNG_RISCV_RVV_IMPLEMENTATION ==
1
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_up_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub3_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_sub4_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg3_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_avg4_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth3_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(
void, png_read_filter_row_paeth4_rvv,
(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),
PNG_EMPTY);
#endif
/* 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 /* SEQUENTIAL_READ */
/* Initialize the row buffers, etc. */
PNG_INTERNAL_FUNCTION(
void, png_read_start_row,
(png_structrp png_ptr),
PNG_EMPTY);
#if ZLIB_VERNUM >=
0x1240
PNG_INTERNAL_FUNCTION(
int, png_zlib_inflate,
(png_structrp png_ptr,
int flush),
PNG_EMPTY);
# define PNG_INFLATE(pp, flush) png_zlib_inflate(pp, flush)
#else /* Zlib < 1.2.4 */
# define PNG_INFLATE(pp, flush) inflate(&(pp)->zstream, flush)
#endif /* Zlib < 1.2.4 */
#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
/* Shared transform functions, defined in pngtran.c */
#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
#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
#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
/* The following decodes the appropriate chunks, and does error correction,
* then calls the appropriate callback for the chunk if it is valid.
*/
typedef enum
{
/* Result of a call to png_handle_chunk made to handle the current chunk
* png_struct::chunk_name on read. Always informational, either the stream
* is read for the next chunk or the routine will call png_error.
*
* NOTE: order is important internally. handled_saved and above are regarded
* as handling the chunk.
*/
handled_error =
0, /* bad crc or known and bad format or too long */
handled_discarded, /* not saved in the unknown chunk list */
handled_saved, /* saved in the unknown chunk list */
handled_ok /* known, supported and handled without error */
} png_handle_result_code;
PNG_INTERNAL_FUNCTION(png_handle_result_code, 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.
*/
PNG_INTERNAL_FUNCTION(png_handle_result_code, png_handle_chunk,
(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),
PNG_EMPTY);
/* This handles the current chunk png_ptr->chunk_name with unread
* data[length] and returns one of the above result codes.
*/
#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
defined(PNG_HANDLE_AS_UNKNOWN_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 /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
/* 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_save_buffer,
(png_structrp png_ptr),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void, png_push_restore_buffer,
(png_structrp png_ptr, png_bytep buffer, 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, 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_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);
#endif /* PROGRESSIVE_READ */
#ifdef PNG_APNG_SUPPORTED
PNG_INTERNAL_FUNCTION(void,png_ensure_fcTL_is_valid,(png_structp png_ptr,
png_uint_32 width, png_uint_32 height,
png_uint_32 x_offset, png_uint_32 y_offset,
png_uint_16 delay_num, png_uint_16 delay_den,
png_byte dispose_op, png_byte blend_op),PNG_EMPTY);
#ifdef PNG_READ_APNG_SUPPORTED
PNG_INTERNAL_FUNCTION(void,png_handle_acTL,(png_structp png_ptr,
png_infop info_ptr, png_uint_32 length),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_handle_fcTL,(png_structp png_ptr,
png_infop info_ptr, png_uint_32 length),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_handle_fdAT,(png_structp png_ptr,
png_infop info_ptr, png_uint_32 length),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_have_info,(png_structp png_ptr,
png_infop info_ptr),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_ensure_sequence_number,(png_structp png_ptr,
png_uint_32 length),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_read_reset,(png_structp png_ptr),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_read_reinit,(png_structp png_ptr,
png_infop info_ptr),PNG_EMPTY);
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
PNG_INTERNAL_FUNCTION(void,png_progressive_read_reset,(png_structp png_ptr),
PNG_EMPTY);
#endif /* PROGRESSIVE_READ */
#endif /* READ_APNG */
#ifdef PNG_WRITE_APNG_SUPPORTED
PNG_INTERNAL_FUNCTION(void,png_write_acTL,(png_structp png_ptr,
png_uint_32 num_frames, png_uint_32 num_plays),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_write_fcTL,(png_structp png_ptr,
png_uint_32 width, png_uint_32 height,
png_uint_32 x_offset, png_uint_32 y_offset,
png_uint_16 delay_num, png_uint_16 delay_den,
png_byte dispose_op, png_byte blend_op),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_write_fdAT,(png_structp png_ptr,
png_const_bytep data, png_size_t length),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_write_reset,(png_structp png_ptr),PNG_EMPTY);
PNG_INTERNAL_FUNCTION(void,png_write_reinit,(png_structp png_ptr,
png_infop info_ptr, png_uint_32 width, png_uint_32 height),PNG_EMPTY);
#endif /* WRITE_APNG */
#endif /* APNG */
#ifdef PNG_iCCP_SUPPORTED
/* Routines for checking parts of an ICC profile. */
#ifdef PNG_READ_iCCP_SUPPORTED
PNG_INTERNAL_FUNCTION(int, png_icc_check_length,
(png_const_structrp png_ptr,
png_const_charp name, png_uint_32 profile_length),
PNG_EMPTY);
#endif /* READ_iCCP */
PNG_INTERNAL_FUNCTION(int, png_icc_check_header,
(png_const_structrp png_ptr,
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_const_charp name, png_uint_32 profile_length,
png_const_bytep profile /* header plus whole tag table */),
PNG_EMPTY);
#endif /* iCCP */
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
PNG_INTERNAL_FUNCTION(void, png_set_rgb_coefficients,
(png_structrp png_ptr),
PNG_EMPTY);
/* Set the rgb_to_gray coefficients from the cHRM Y values (if unset) */
#endif /* READ_RGB_TO_GRAY */
/* 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, 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, 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 else's!
*
* 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 means 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, size_t size, int *statep, size_t *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, size_t size),
PNG_EMPTY);
#endif /* pCAL || sCAL */
#if defined(PNG_READ_GAMMA_SUPPORTED) ||\
defined(PNG_COLORSPACE_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);
/* 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);
#endif
#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);
/* 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);
/* PNGv3: 'resolve' the file gamma according to the new PNGv3 rules for colour
* space information.
*
* NOTE: this uses precisely those chunks that libpng supports. For example it
* doesn't use iCCP and it can only use cICP for known and manageable
* transforms. For this reason a gamma specified by png_set_gamma always takes
* precedence.
*/
PNG_INTERNAL_FUNCTION(png_fixed_point, png_resolve_file_gamma,
(png_const_structrp png_ptr),
PNG_EMPTY);
/* 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 /* READ_GAMMA */
#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
/* Set the RGB coefficients if not already set by png_set_rgb_to_gray */
PNG_INTERNAL_FUNCTION(void, png_set_rgb_coefficients,
(png_structrp png_ptr),
PNG_EMPTY);
#endif
#if defined(PNG_cHRM_SUPPORTED) || defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)
PNG_INTERNAL_FUNCTION(int, png_XYZ_from_xy,
(png_XYZ *XYZ, const png_xy *xy),
PNG_EMPTY);
#endif /* cHRM || READ_RGB_TO_GRAY */
#ifdef PNG_COLORSPACE_SUPPORTED
PNG_INTERNAL_FUNCTION(int, png_xy_from_XYZ,
(png_xy *xy, const png_XYZ *XYZ),
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. */
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_CALLBACK(void, png_safe_error,
(png_structp png_ptr, png_const_charp error_message),
PNG_NORETURN);
#ifdef PNG_WARNINGS_SUPPORTED
PNG_INTERNAL_CALLBACK(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.
*/
# if PNG_ARM_NEON_OPT >
0
PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
(png_structp png_ptr, unsigned int bpp),
PNG_EMPTY);
#endif
#if PNG_MIPS_MSA_IMPLEMENTATION ==
1
PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_mips,
(png_structp png_ptr, unsigned int bpp),
PNG_EMPTY);
#endif
# if PNG_MIPS_MMI_IMPLEMENTATION >
0
PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_mips,
(png_structp png_ptr, unsigned int bpp),
PNG_EMPTY);
# endif
# if PNG_INTEL_SSE_IMPLEMENTATION >
0
PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
(png_structp png_ptr, unsigned int bpp),
PNG_EMPTY);
# endif
#endif
#if PNG_LOONGARCH_LSX_OPT >
0
PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_lsx,
(png_structp png_ptr, unsigned int bpp),
PNG_EMPTY);
#endif
# if PNG_RISCV_RVV_IMPLEMENTATION ==
1
PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_rvv,
(png_structp png_ptr, unsigned int bpp),
PNG_EMPTY);
#endif
PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword,
(png_structrp png_ptr, png_const_charp key, png_bytep new_key),
PNG_EMPTY);
#if PNG_ARM_NEON_IMPLEMENTATION ==
1
PNG_INTERNAL_FUNCTION(void,
png_riffle_palette_neon,
(png_structrp),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(int,
png_do_expand_palette_rgba8_neon,
(png_structrp,
png_row_infop,
png_const_bytep,
const png_bytepp,
const png_bytepp),
PNG_EMPTY);
PNG_INTERNAL_FUNCTION(int,
png_do_expand_palette_rgb8_neon,
(png_structrp,
png_row_infop,
png_const_bytep,
const png_bytepp,
const png_bytepp),
PNG_EMPTY);
#endif
/* Maintainer: Put new private prototypes here ^ */
#include "pngdebug.h"
#ifdef __cplusplus
}
#endif
#endif /* PNG_VERSION_INFO_ONLY */
