2 /* pngpriv.h - private declarations for use inside libpng
4 * Copyright (c) 2018-2019 Cosmin Truta
5 * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
6 * Copyright (c) 1996-1997 Andreas Dilger
7 * Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.
9 * This code is released under the libpng license.
10 * For conditions of distribution and use, see the disclaimer
11 * and license in png.h
14 /* The symbols declared in this file (including the functions declared
15 * as extern) are PRIVATE. They are not part of the libpng public
16 * interface, and are not recommended for use by regular applications.
17 * Some of them may become public in the future; others may stay private,
18 * change in an incompatible way, or even disappear.
19 * Although the libpng users are not forbidden to include this header,
20 * they should be well aware of the issues that may arise from doing so.
26 /* Feature Test Macros. The following are defined here to ensure that correctly
27 * implemented libraries reveal the APIs libpng needs to build and hide those
28 * that are not needed and potentially damaging to the compilation.
30 * Feature Test Macros must be defined before any system header is included (see
31 * POSIX 1003.1 2.8.2 "POSIX Symbols."
33 * These macros only have an effect if the operating system supports either
34 * POSIX 1003.1 or C99, or both. On other operating systems (particularly
35 * Windows/Visual Studio) there is no effect; the OS specific tests below are
36 * still required (as of 2011-05-02.)
39 # define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
42 #ifndef PNG_VERSION_INFO_ONLY
43 /* Standard library headers not required by png.h: */
48 #define PNGLIB_BUILD /*libpng is being built, not used*/
50 /* If HAVE_CONFIG_H is defined during the build then the build system must
51 * provide an appropriate "config.h" file on the include path. The header file
52 * must provide definitions as required below (search for "HAVE_CONFIG_H");
53 * see configure.ac for more details of the requirements. The macro
54 * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on
55 * 'configure'; define this macro to prevent the configure build including the
56 * configure generated config.h. Libpng is expected to compile without *any*
57 * special build system support on a reasonably ANSI-C compliant system.
59 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
62 /* Pick up the definition of 'restrict' from config.h if it was read: */
63 # define PNG_RESTRICT restrict
66 /* To support symbol prefixing it is necessary to know *before* including png.h
67 * whether the fixed point (and maybe other) APIs are exported, because if they
68 * are not internal definitions may be required. This is handled below just
69 * before png.h is included, but load the configuration now if it is available.
72 # include "pnglibconf.h"
75 /* Local renames may change non-exported API functions from png.h */
76 #if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
77 # include "pngprefix.h"
80 #ifdef PNG_USER_CONFIG
82 /* These should have been defined in pngusr.h */
83 # ifndef PNG_USER_PRIVATEBUILD
84 # define PNG_USER_PRIVATEBUILD "Custom libpng build"
86 # ifndef PNG_USER_DLLFNAME_POSTFIX
87 # define PNG_USER_DLLFNAME_POSTFIX "Cb"
91 /* Compile time options.
92 * =====================
93 * In a multi-arch build the compiler may compile the code several times for the
94 * same object module, producing different binaries for different architectures.
95 * When this happens configure-time setting of the target host options cannot be
96 * done and this interferes with the handling of the ARM NEON optimizations, and
97 * possibly other similar optimizations. Put additional tests here; in general
98 * this is needed when the same option can be changed at both compile time and
99 * run time depending on the target OS (i.e. iOS vs Android.)
101 * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
102 * this is not possible with certain compilers (Oracle SUN OS CC), as a result
103 * it is necessary to ensure that all extern functions that *might* be used
104 * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__
105 * below is one example of this behavior because it is controlled by the
106 * presence or not of -mfpu=neon on the GCC command line, it is possible to do
107 * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
110 #ifndef PNG_ARM_NEON_OPT
111 /* ARM NEON optimizations are being controlled by the compiler settings,
112 * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon
113 * with GCC) then the compiler will define __ARM_NEON__ and we can rely
114 * unconditionally on NEON instructions not crashing, otherwise we must
115 * disable use of NEON instructions.
117 * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
118 * can only be turned on automatically if that is supported too. If
119 * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
120 * to compile with an appropriate #error if ALIGNED_MEMORY has been turned
123 * Note that gcc-4.9 defines __ARM_NEON instead of the deprecated
124 * __ARM_NEON__, so we check both variants.
126 * To disable ARM_NEON optimizations entirely, and skip compiling the
127 * associated assembler code, pass --enable-arm-neon=no to configure
128 * or put -DPNG_ARM_NEON_OPT=0 in CPPFLAGS.
130 # if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \
131 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
132 # define PNG_ARM_NEON_OPT 2
134 # define PNG_ARM_NEON_OPT 0
138 #if PNG_ARM_NEON_OPT > 0
139 /* NEON optimizations are to be at least considered by libpng, so enable the
140 * callbacks to do this.
142 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
144 /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used
145 * if possible - if __ARM_NEON__ is set and the compiler version is not known
146 * to be broken. This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can
149 * 1 The intrinsics code (the default with __ARM_NEON__)
150 * 2 The hand coded assembler (the default without __ARM_NEON__)
152 * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however
153 * this is *NOT* supported and may cease to work even after a minor revision
154 * to libpng. It *is* valid to do this for testing purposes, e.g. speed
155 * testing or a new compiler, but the results should be communicated to the
156 * libpng implementation list for incorporation in the next minor release.
158 # ifndef PNG_ARM_NEON_IMPLEMENTATION
159 # if defined(__ARM_NEON__) || defined(__ARM_NEON)
160 # if defined(__clang__)
161 /* At present it is unknown by the libpng developers which versions
162 * of clang support the intrinsics, however some or perhaps all
163 * versions do not work with the assembler so this may be
164 * irrelevant, so just use the default (do nothing here.)
166 # elif defined(__GNUC__)
167 /* GCC 4.5.4 NEON support is known to be broken. 4.6.3 is known to
168 * work, so if this *is* GCC, or G++, look for a version >4.5
170 # if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)
171 # define PNG_ARM_NEON_IMPLEMENTATION 2
172 # endif /* no GNUC support */
173 # endif /* __GNUC__ */
174 # else /* !defined __ARM_NEON__ */
175 /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
177 # if !defined(__aarch64__)
178 /* The assembler code currently does not work on ARM64 */
179 # define PNG_ARM_NEON_IMPLEMENTATION 2
180 # endif /* __aarch64__ */
181 # endif /* __ARM_NEON__ */
182 # endif /* !PNG_ARM_NEON_IMPLEMENTATION */
184 # ifndef PNG_ARM_NEON_IMPLEMENTATION
185 /* Use the intrinsics code by default. */
186 # define PNG_ARM_NEON_IMPLEMENTATION 1
188 #endif /* PNG_ARM_NEON_OPT > 0 */
190 #ifndef PNG_MIPS_MSA_OPT
191 # if defined(__mips_msa) && (__mips_isa_rev >= 5) && defined(PNG_ALIGNED_MEMORY_SUPPORTED)
192 # define PNG_MIPS_MSA_OPT 2
194 # define PNG_MIPS_MSA_OPT 0
198 #ifndef PNG_POWERPC_VSX_OPT
199 # if defined(__PPC64__) && defined(__ALTIVEC__) && defined(__VSX__)
200 # define PNG_POWERPC_VSX_OPT 2
202 # define PNG_POWERPC_VSX_OPT 0
206 #ifndef PNG_INTEL_SSE_OPT
207 # ifdef PNG_INTEL_SSE
208 /* Only check for SSE if the build configuration has been modified to
209 * enable SSE optimizations. This means that these optimizations will
210 * be off by default. See contrib/intel for more details.
212 # if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
213 defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
214 (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
215 # define PNG_INTEL_SSE_OPT 1
217 # define PNG_INTEL_SSE_OPT 0
220 # define PNG_INTEL_SSE_OPT 0
224 #if PNG_INTEL_SSE_OPT > 0
225 # ifndef PNG_INTEL_SSE_IMPLEMENTATION
226 # if defined(__SSE4_1__) || defined(__AVX__)
227 /* We are not actually using AVX, but checking for AVX is the best
228 way we can detect SSE4.1 and SSSE3 on MSVC.
230 # define PNG_INTEL_SSE_IMPLEMENTATION 3
231 # elif defined(__SSSE3__)
232 # define PNG_INTEL_SSE_IMPLEMENTATION 2
233 # elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
234 (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
235 # define PNG_INTEL_SSE_IMPLEMENTATION 1
237 # define PNG_INTEL_SSE_IMPLEMENTATION 0
241 # if PNG_INTEL_SSE_IMPLEMENTATION > 0
242 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
245 # define PNG_INTEL_SSE_IMPLEMENTATION 0
248 #if PNG_MIPS_MSA_OPT > 0
249 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_msa
250 # ifndef PNG_MIPS_MSA_IMPLEMENTATION
251 # if defined(__mips_msa)
252 # if defined(__clang__)
253 # elif defined(__GNUC__)
254 # if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
255 # define PNG_MIPS_MSA_IMPLEMENTATION 2
256 # endif /* no GNUC support */
257 # endif /* __GNUC__ */
258 # else /* !defined __mips_msa */
259 # define PNG_MIPS_MSA_IMPLEMENTATION 2
260 # endif /* __mips_msa */
261 # endif /* !PNG_MIPS_MSA_IMPLEMENTATION */
263 # ifndef PNG_MIPS_MSA_IMPLEMENTATION
264 # define PNG_MIPS_MSA_IMPLEMENTATION 1
266 #endif /* PNG_MIPS_MSA_OPT > 0 */
268 #if PNG_POWERPC_VSX_OPT > 0
269 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
270 # define PNG_POWERPC_VSX_IMPLEMENTATION 1
274 /* Is this a build of a DLL where compilation of the object modules requires
275 * different preprocessor settings to those required for a simple library? If
276 * so PNG_BUILD_DLL must be set.
278 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
279 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
280 * static library of libpng then link the DLL against that.
282 #ifndef PNG_BUILD_DLL
284 /* This is set by libtool when files are compiled for a DLL; libtool
285 * always compiles twice, even on systems where it isn't necessary. Set
286 * PNG_BUILD_DLL in case it is necessary:
288 # define PNG_BUILD_DLL
291 /* This is set by the Microsoft Visual Studio IDE in projects that
292 * build a DLL. It can't easily be removed from those projects (it
293 * isn't visible in the Visual Studio UI) so it is a fairly reliable
294 * indication that PNG_IMPEXP needs to be set to the DLL export
297 # define PNG_BUILD_DLL
300 /* This is set by the Borland C system when compiling for a DLL
303 # define PNG_BUILD_DLL
305 /* Add additional compiler cases here. */
309 #endif /* Setting PNG_BUILD_DLL if required */
311 /* See pngconf.h for more details: the builder of the library may set this on
312 * the command line to the right thing for the specific compilation system or it
313 * may be automagically set above (at present we know of no system where it does
314 * need to be set on the command line.)
316 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
317 * setting it to the "import" setting for a DLL build.
320 # ifdef PNG_BUILD_DLL
321 # define PNG_IMPEXP PNG_DLL_EXPORT
323 /* Not building a DLL, or the DLL doesn't require specific export
330 /* No warnings for private or deprecated functions in the build: */
331 #ifndef PNG_DEPRECATED
332 # define PNG_DEPRECATED
338 /* Symbol preprocessing support.
340 * To enable listing global, but internal, symbols the following macros should
341 * always be used to declare an extern data or function object in this file.
343 #ifndef PNG_INTERNAL_DATA
344 # define PNG_INTERNAL_DATA(type, name, array) PNG_LINKAGE_DATA type name array
347 #ifndef PNG_INTERNAL_FUNCTION
348 # define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
349 PNG_LINKAGE_FUNCTION PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
352 #ifndef PNG_INTERNAL_CALLBACK
353 # define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
354 PNG_LINKAGE_CALLBACK PNG_FUNCTION(type, (PNGCBAPI name), args,\
355 PNG_EMPTY attributes)
358 /* If floating or fixed point APIs are disabled they may still be compiled
359 * internally. To handle this make sure they are declared as the appropriate
360 * internal extern function (otherwise the symbol prefixing stuff won't work and
361 * the functions will be used without definitions.)
363 * NOTE: although all the API functions are declared here they are not all
364 * actually built! Because the declarations are still made it is necessary to
365 * fake out types that they depend on.
367 #ifndef PNG_FP_EXPORT
368 # ifndef PNG_FLOATING_POINT_SUPPORTED
369 # define PNG_FP_EXPORT(ordinal, type, name, args)\
370 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
371 # ifndef PNG_VERSION_INFO_ONLY
372 typedef struct png_incomplete png_double;
373 typedef png_double* png_doublep;
374 typedef const png_double* png_const_doublep;
375 typedef png_double** png_doublepp;
379 #ifndef PNG_FIXED_EXPORT
380 # ifndef PNG_FIXED_POINT_SUPPORTED
381 # define PNG_FIXED_EXPORT(ordinal, type, name, args)\
382 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
388 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
389 #ifndef PNG_DLL_EXPORT
390 # define PNG_DLL_EXPORT
393 /* This is a global switch to set the compilation for an installed system
394 * (a release build). It can be set for testing debug builds to ensure that
395 * they will compile when the build type is switched to RC or STABLE, the
396 * default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS
399 * -DPNG_RELEASE_BUILD Turns on the release compile path
400 * -DPNG_RELEASE_BUILD=0 Turns it off
401 * or in your pngusr.h with
402 * #define PNG_RELEASE_BUILD=1 Turns on the release compile path
403 * #define PNG_RELEASE_BUILD=0 Turns it off
405 #ifndef PNG_RELEASE_BUILD
406 # define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC)
409 /* SECURITY and SAFETY:
411 * libpng is built with support for internal limits on image dimensions and
412 * memory usage. These are documented in scripts/pnglibconf.dfa of the
413 * source and recorded in the machine generated header file pnglibconf.h.
416 /* If you are running on a machine where you cannot allocate more
417 * than 64K of memory at once, uncomment this. While libpng will not
418 * normally need that much memory in a chunk (unless you load up a very
419 * large file), zlib needs to know how big of a chunk it can use, and
420 * libpng thus makes sure to check any memory allocation to verify it
421 * will fit into memory.
423 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
424 * same limit and pngconf.h (already included) sets the limit
425 * if certain operating systems are detected.
427 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
428 # define PNG_MAX_MALLOC_64K
432 /* Unused formal parameter warnings are silenced using the following macro
433 * which is expected to have no bad effects on performance (optimizing
434 * compilers will probably remove it entirely). Note that if you replace
435 * it with something other than whitespace, you must include the terminating
438 # define PNG_UNUSED(param) (void)param;
441 /* Just a little check that someone hasn't tried to define something
444 #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
445 # undef PNG_ZBUF_SIZE
446 # define PNG_ZBUF_SIZE 65536L
449 /* If warnings or errors are turned off the code is disabled or redirected here.
450 * From 1.5.4 functions have been added to allow very limited formatting of
451 * error and warning messages - this code will also be disabled here.
453 #ifdef PNG_WARNINGS_SUPPORTED
454 # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
456 # define png_warning_parameter(p,number,string) ((void)0)
457 # define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
458 # define png_warning_parameter_signed(p,number,format,value) ((void)0)
459 # define png_formatted_warning(pp,p,message) ((void)(pp))
460 # define PNG_WARNING_PARAMETERS(p)
462 #ifndef PNG_ERROR_TEXT_SUPPORTED
463 # define png_fixed_error(s1,s2) png_err(s1)
466 /* Some fixed point APIs are still required even if not exported because
467 * they get used by the corresponding floating point APIs. This magic
470 #ifdef PNG_FIXED_POINT_SUPPORTED
471 # define PNGFAPI PNGAPI
473 # define PNGFAPI /* PRIVATE */
476 #ifndef PNG_VERSION_INFO_ONLY
477 /* Other defines specific to compilers can go here. Try to keep
478 * them inside an appropriate ifdef/endif pair for portability.
481 /* C allows up-casts from (void*) to any pointer and (const void*) to any
482 * pointer to a const object. C++ regards this as a type error and requires an
483 * explicit, static, cast and provides the static_cast<> rune to ensure that
484 * const is not cast away.
487 # define png_voidcast(type, value) static_cast<type>(value)
488 # define png_constcast(type, value) const_cast<type>(value)
489 # define png_aligncast(type, value) \
490 static_cast<type>(static_cast<void*>(value))
491 # define png_aligncastconst(type, value) \
492 static_cast<type>(static_cast<const void*>(value))
494 # define png_voidcast(type, value) (value)
497 typedef unsigned long long png_ptruint;
499 typedef unsigned __int64 png_ptruint;
502 typedef unsigned long png_ptruint;
504 # define png_constcast(type, value) ((type)(png_ptruint)(const void*)(value))
505 # define png_aligncast(type, value) ((void*)(value))
506 # define png_aligncastconst(type, value) ((const void*)(value))
507 #endif /* __cplusplus */
509 #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
510 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
511 /* png.c requires the following ANSI-C constants if the conversion of
512 * floating point to ASCII is implemented therein:
514 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
515 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
516 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
520 # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
521 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
522 /* We need to check that <math.h> hasn't already been included earlier
523 * as it seems it doesn't agree with <fp.h>, yet we should really use
524 * <fp.h> if possible.
526 # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
532 # if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
533 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
540 /* This provides the non-ANSI (far) memory allocation routines. */
541 #if defined(__TURBOC__) && defined(__MSDOS__)
546 #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
547 defined(_WIN32) || defined(__WIN32__)
548 # include <windows.h> /* defines _WINDOWS_ macro */
550 #endif /* PNG_VERSION_INFO_ONLY */
552 /* Moved here around 1.5.0beta36 from pngconf.h */
553 /* Users may want to use these so they are not private. Any library
554 * functions that are passed far data must be model-independent.
557 /* Memory model/platform independent fns */
560 # define PNG_ABORT() ExitProcess(0)
562 # define PNG_ABORT() abort()
566 /* These macros may need to be architecture dependent. */
567 #define PNG_ALIGN_NONE 0 /* do not use data alignment */
568 #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
570 # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
572 # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
574 #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
576 #ifndef PNG_ALIGN_TYPE
577 /* Default to using aligned access optimizations and requiring alignment to a
578 * multiple of the data type size. Override in a compiler specific fashion
579 * if necessary by inserting tests here:
581 # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
584 #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
585 /* This is used because in some compiler implementations non-aligned
586 * structure members are supported, so the offsetof approach below fails.
587 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
588 * is good for performance. Do not do this unless you have tested the result
591 # define png_alignof(type) (sizeof (type))
593 # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
594 # define png_alignof(type) offsetof(struct{char c; type t;}, t)
596 # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
597 # define png_alignof(type) (1)
599 /* Else leave png_alignof undefined to prevent use thereof */
603 /* This implicitly assumes alignment is always to a power of 2. */
605 # define png_isaligned(ptr, type)\
606 (((type)((const char*)ptr-(const char*)0) & \
607 (type)(png_alignof(type)-1)) == 0)
609 # define png_isaligned(ptr, type) 0
612 /* End of memory model/platform independent support */
613 /* End of 1.5.0beta36 move from pngconf.h */
615 /* CONSTANTS and UTILITY MACROS
616 * These are used internally by libpng and not exposed in the API
619 /* Various modes of operation. Note that after an init, mode is set to
620 * zero automatically when the structure is created. Three of these
621 * are defined in png.h because they need to be visible to applications
622 * that call png_set_unknown_chunk().
624 /* #define PNG_HAVE_IHDR 0x01U (defined in png.h) */
625 /* #define PNG_HAVE_PLTE 0x02U (defined in png.h) */
626 #define PNG_HAVE_IDAT 0x04U
627 /* #define PNG_AFTER_IDAT 0x08U (defined in png.h) */
628 #define PNG_HAVE_IEND 0x10U
632 #define PNG_HAVE_CHUNK_HEADER 0x100U
633 #define PNG_WROTE_tIME 0x200U
634 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400U
635 #define PNG_BACKGROUND_IS_GRAY 0x800U
636 #define PNG_HAVE_PNG_SIGNATURE 0x1000U
637 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000U /* Have another chunk after IDAT */
638 /* 0x4000U (unused) */
639 #define PNG_IS_READ_STRUCT 0x8000U /* Else is a write struct */
640 #ifdef PNG_APNG_SUPPORTED
641 #define PNG_HAVE_acTL 0x10000U
642 #define PNG_HAVE_fcTL 0x20000U
645 /* Flags for the transformations the PNG library does on the image data */
646 #define PNG_BGR 0x0001U
647 #define PNG_INTERLACE 0x0002U
648 #define PNG_PACK 0x0004U
649 #define PNG_SHIFT 0x0008U
650 #define PNG_SWAP_BYTES 0x0010U
651 #define PNG_INVERT_MONO 0x0020U
652 #define PNG_QUANTIZE 0x0040U
653 #define PNG_COMPOSE 0x0080U /* Was PNG_BACKGROUND */
654 #define PNG_BACKGROUND_EXPAND 0x0100U
655 #define PNG_EXPAND_16 0x0200U /* Added to libpng 1.5.2 */
656 #define PNG_16_TO_8 0x0400U /* Becomes 'chop' in 1.5.4 */
657 #define PNG_RGBA 0x0800U
658 #define PNG_EXPAND 0x1000U
659 #define PNG_GAMMA 0x2000U
660 #define PNG_GRAY_TO_RGB 0x4000U
661 #define PNG_FILLER 0x8000U
662 #define PNG_PACKSWAP 0x10000U
663 #define PNG_SWAP_ALPHA 0x20000U
664 #define PNG_STRIP_ALPHA 0x40000U
665 #define PNG_INVERT_ALPHA 0x80000U
666 #define PNG_USER_TRANSFORM 0x100000U
667 #define PNG_RGB_TO_GRAY_ERR 0x200000U
668 #define PNG_RGB_TO_GRAY_WARN 0x400000U
669 #define PNG_RGB_TO_GRAY 0x600000U /* two bits, RGB_TO_GRAY_ERR|WARN */
670 #define PNG_ENCODE_ALPHA 0x800000U /* Added to libpng-1.5.4 */
671 #define PNG_ADD_ALPHA 0x1000000U /* Added to libpng-1.2.7 */
672 #define PNG_EXPAND_tRNS 0x2000000U /* Added to libpng-1.2.9 */
673 #define PNG_SCALE_16_TO_8 0x4000000U /* Added to libpng-1.5.4 */
674 /* 0x8000000U unused */
675 /* 0x10000000U unused */
676 /* 0x20000000U unused */
677 /* 0x40000000U unused */
678 /* Flags for png_create_struct */
679 #define PNG_STRUCT_PNG 0x0001U
680 #define PNG_STRUCT_INFO 0x0002U
682 /* Flags for the png_ptr->flags rather than declaring a byte for each one */
683 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001U
684 #define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002U /* Added to libpng-1.6.0 */
686 #define PNG_FLAG_ZSTREAM_ENDED 0x0008U /* Added to libpng-1.6.0 */
689 #define PNG_FLAG_ROW_INIT 0x0040U
690 #define PNG_FLAG_FILLER_AFTER 0x0080U
691 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100U
692 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200U
693 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400U
694 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800U
695 #define PNG_FLAG_ASSUME_sRGB 0x1000U /* Added to libpng-1.5.4 */
696 #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000U /* Added to libpng-1.5.4 */
697 #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000U /* Added to libpng-1.5.4 */
698 /* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000U */
699 /* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000U */
700 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000U
701 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000U
702 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000U
703 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000U /* Added to libpng-1.4.0 */
704 #define PNG_FLAG_APP_WARNINGS_WARN 0x200000U /* Added to libpng-1.6.0 */
705 #define PNG_FLAG_APP_ERRORS_WARN 0x400000U /* Added to libpng-1.6.0 */
706 /* 0x800000U unused */
707 /* 0x1000000U unused */
708 /* 0x2000000U unused */
709 /* 0x4000000U unused */
710 /* 0x8000000U unused */
711 /* 0x10000000U unused */
712 /* 0x20000000U unused */
713 /* 0x40000000U unused */
715 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
716 PNG_FLAG_CRC_ANCILLARY_NOWARN)
718 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
719 PNG_FLAG_CRC_CRITICAL_IGNORE)
721 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
722 PNG_FLAG_CRC_CRITICAL_MASK)
724 /* Save typing and make code easier to understand */
726 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
727 abs((int)((c1).green) - (int)((c2).green)) + \
728 abs((int)((c1).blue) - (int)((c2).blue)))
730 /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
731 * by dividing by 257 *with rounding*. This macro is exact for the given range.
732 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the
733 * macro were established by experiment (modifying the added value). The macro
734 * has a second variant that takes a value already scaled by 255 and divides by
735 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it
736 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
738 #define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
739 #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
741 /* Added to libpng-1.2.6 JB */
742 #define PNG_ROWBYTES(pixel_bits, width) \
743 ((pixel_bits) >= 8 ? \
744 ((size_t)(width) * (((size_t)(pixel_bits)) >> 3)) : \
745 (( ((size_t)(width) * ((size_t)(pixel_bits))) + 7) >> 3) )
747 /* This returns the number of trailing bits in the last byte of a row, 0 if the
748 * last byte is completely full of pixels. It is, in principle, (pixel_bits x
749 * width) % 8, but that would overflow for large 'width'. The second macro is
750 * the same except that it returns the number of unused bits in the last byte;
751 * (8-TRAILBITS), but 0 when TRAILBITS is 0.
753 * NOTE: these macros are intended to be self-evidently correct and never
754 * overflow on the assumption that pixel_bits is in the range 0..255. The
755 * arguments are evaluated only once and they can be signed (e.g. as a result of
756 * the integral promotions). The result of the expression always has type
757 * (png_uint_32), however the compiler always knows it is in the range 0..7.
759 #define PNG_TRAILBITS(pixel_bits, width) \
760 (((pixel_bits) * ((width) % (png_uint_32)8)) % 8)
762 #define PNG_PADBITS(pixel_bits, width) \
763 ((8 - PNG_TRAILBITS(pixel_bits, width)) % 8)
765 /* PNG_OUT_OF_RANGE returns true if value is outside the range
766 * ideal-delta..ideal+delta. Each argument is evaluated twice.
767 * "ideal" and "delta" should be constants, normally simple
768 * integers, "value" a variable. Added to libpng-1.2.6 JB
770 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
771 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
773 /* Conversions between fixed and floating point, only defined if
774 * required (to make sure the code doesn't accidentally use float
775 * when it is supposedly disabled.)
777 #ifdef PNG_FLOATING_POINT_SUPPORTED
778 /* The floating point conversion can't overflow, though it can and
779 * does lose accuracy relative to the original fixed point value.
780 * In practice this doesn't matter because png_fixed_point only
781 * stores numbers with very low precision. The png_ptr and s
782 * arguments are unused by default but are there in case error
783 * checking becomes a requirement.
785 #define png_float(png_ptr, fixed, s) (.00001 * (fixed))
787 /* The fixed point conversion performs range checking and evaluates
788 * its argument multiple times, so must be used with care. The
789 * range checking uses the PNG specification values for a signed
790 * 32-bit fixed point value except that the values are deliberately
791 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
792 * (2^31-1) * 100000). 's' is a string that describes the value being
795 * NOTE: this macro will raise a png_error if the range check fails,
796 * therefore it is normally only appropriate to use this on values
797 * that come from API calls or other sources where an out of range
798 * error indicates a programming error, not a data error!
800 * NOTE: by default this is off - the macro is not used - because the
801 * function call saves a lot of code.
803 #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
804 #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
805 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
807 /* else the corresponding function is defined below, inside the scope of the
812 /* Constants for known chunk types. If you need to add a chunk, define the name
813 * here. For historical reasons these constants have the form png_<name>; i.e.
814 * the prefix is lower case. Please use decimal values as the parameters to
815 * match the ISO PNG specification and to avoid relying on the C locale
816 * interpretation of character values.
818 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
819 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
820 * to be generated if required.
822 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
823 * architectures where (int) is only 16 bits.
825 #define PNG_32b(b,s) ((png_uint_32)(b) << (s))
826 #define PNG_U32(b1,b2,b3,b4) \
827 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
829 /* Constants for known chunk types.
831 * MAINTAINERS: If you need to add a chunk, define the name here.
832 * For historical reasons these constants have the form png_<name>; i.e.
833 * the prefix is lower case. Please use decimal values as the parameters to
834 * match the ISO PNG specification and to avoid relying on the C locale
835 * interpretation of character values. Please keep the list sorted.
837 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
838 * type. In fact the specification does not express chunk types this way,
839 * however using a 32-bit value means that the chunk type can be read from the
840 * stream using exactly the same code as used for a 32-bit unsigned value and
841 * can be examined far more efficiently (using one arithmetic compare).
843 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The
844 * libpng API still uses strings for 'unknown' chunks and a macro,
845 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice
846 * that for portable code numeric values must still be used; the string "IHDR"
847 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
849 * In 1.7.0 the definitions will be made public in png.h to avoid having to
850 * duplicate the same definitions in application code.
852 #define png_IDAT PNG_U32( 73, 68, 65, 84)
853 #define png_IEND PNG_U32( 73, 69, 78, 68)
854 #define png_IHDR PNG_U32( 73, 72, 68, 82)
855 #define png_PLTE PNG_U32( 80, 76, 84, 69)
856 #define png_bKGD PNG_U32( 98, 75, 71, 68)
857 #define png_cHRM PNG_U32( 99, 72, 82, 77)
858 #define png_eXIf PNG_U32(101, 88, 73, 102) /* registered July 2017 */
859 #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
860 #define png_gAMA PNG_U32(103, 65, 77, 65)
861 #define png_gIFg PNG_U32(103, 73, 70, 103)
862 #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
863 #define png_gIFx PNG_U32(103, 73, 70, 120)
864 #define png_hIST PNG_U32(104, 73, 83, 84)
865 #define png_iCCP PNG_U32(105, 67, 67, 80)
866 #define png_iTXt PNG_U32(105, 84, 88, 116)
867 #define png_oFFs PNG_U32(111, 70, 70, 115)
868 #define png_pCAL PNG_U32(112, 67, 65, 76)
869 #define png_pHYs PNG_U32(112, 72, 89, 115)
870 #define png_sBIT PNG_U32(115, 66, 73, 84)
871 #define png_sCAL PNG_U32(115, 67, 65, 76)
872 #define png_sPLT PNG_U32(115, 80, 76, 84)
873 #define png_sRGB PNG_U32(115, 82, 71, 66)
874 #define png_sTER PNG_U32(115, 84, 69, 82)
875 #define png_tEXt PNG_U32(116, 69, 88, 116)
876 #define png_tIME PNG_U32(116, 73, 77, 69)
877 #define png_tRNS PNG_U32(116, 82, 78, 83)
878 #define png_zTXt PNG_U32(122, 84, 88, 116)
880 #ifdef PNG_APNG_SUPPORTED
881 #define png_acTL PNG_U32( 97, 99, 84, 76)
882 #define png_fcTL PNG_U32(102, 99, 84, 76)
883 #define png_fdAT PNG_U32(102, 100, 65, 84)
885 /* For png_struct.apng_flags: */
886 #define PNG_FIRST_FRAME_HIDDEN 0x0001U
887 #define PNG_APNG_APP 0x0002U
890 /* The following will work on (signed char*) strings, whereas the get_uint_32
891 * macro will fail on top-bit-set values because of the sign extension.
893 #define PNG_CHUNK_FROM_STRING(s)\
894 PNG_U32(0xff & (s)[0], 0xff & (s)[1], 0xff & (s)[2], 0xff & (s)[3])
896 /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
897 * signed and the argument is a (char[]) This macro will fail miserably on
898 * systems where (char) is more than 8 bits.
900 #define PNG_STRING_FROM_CHUNK(s,c)\
901 (void)(((char*)(s))[0]=(char)(((c)>>24) & 0xff), \
902 ((char*)(s))[1]=(char)(((c)>>16) & 0xff),\
903 ((char*)(s))[2]=(char)(((c)>>8) & 0xff), \
904 ((char*)(s))[3]=(char)((c & 0xff)))
906 /* Do the same but terminate with a null character. */
907 #define PNG_CSTRING_FROM_CHUNK(s,c)\
908 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
910 /* Test on flag values as defined in the spec (section 5.4): */
911 #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
912 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
913 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
914 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
915 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
917 /* Gamma values (new at libpng-1.5.4): */
918 #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
919 #define PNG_GAMMA_MAC_INVERSE 65909
920 #define PNG_GAMMA_sRGB_INVERSE 45455
922 /* Almost everything below is C specific; the #defines above can be used in
923 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
925 #ifndef PNG_VERSION_INFO_ONLY
927 #include "pngstruct.h"
930 /* Validate the include paths - the include path used to generate pnglibconf.h
931 * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
933 #if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
934 # error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
935 "-I (include path) error: see the notes in pngpriv.h"
936 /* This means that when pnglibconf.h was built the copy of zlib.h that it
937 * used is not the same as the one being used here. Because the build of
938 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
939 * zlib version number and because this affects handling of certain broken
940 * PNG files the -I directives must match.
942 * The most likely explanation is that you passed a -I in CFLAGS. This will
943 * not work; all the preprocessor directives and in particular all the -I
944 * directives must be in CPPFLAGS.
948 /* This is used for 16-bit gamma tables -- only the top level pointers are
949 * const; this could be changed:
951 typedef const png_uint_16p * png_const_uint_16pp;
953 /* Added to libpng-1.5.7: sRGB conversion tables */
954 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
955 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
956 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED
957 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
958 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
959 * 0..65535. This table gives the closest 16-bit answers (no errors).
963 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
964 PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
966 #define PNG_sRGB_FROM_LINEAR(linear) \
967 ((png_byte)(0xff & ((png_sRGB_base[(linear)>>15] \
968 + ((((linear) & 0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8)))
969 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
970 * encoded value with maximum error 0.646365. Note that the input is not a
971 * 16-bit value; it has been multiplied by 255! */
972 #endif /* SIMPLIFIED_READ/WRITE */
975 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
978 #endif /* __cplusplus */
980 /* Internal functions; these are not exported from a DLL however because they
981 * are used within several of the C source files they have to be C extern.
983 * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
987 #define PNG_UNEXPECTED_ZLIB_RETURN (-7)
988 PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
990 /* Used by the zlib handling functions to ensure that z_stream::msg is always
991 * set before they return.
994 #ifdef PNG_WRITE_SUPPORTED
995 PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
996 png_compression_bufferp *list),PNG_EMPTY);
997 /* Free the buffer list used by the compressed write code. */
1000 #if defined(PNG_FLOATING_POINT_SUPPORTED) && \
1001 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
1002 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
1003 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
1004 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
1005 (defined(PNG_sCAL_SUPPORTED) && \
1006 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
1007 PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
1008 double fp, png_const_charp text),PNG_EMPTY);
1011 /* Check the user version string for compatibility, returns false if the version
1012 * numbers aren't compatible.
1014 PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
1015 png_const_charp user_png_ver),PNG_EMPTY);
1017 /* Internal base allocator - no messages, NULL on failure to allocate. This
1018 * does, however, call the application provided allocator and that could call
1019 * png_error (although that would be a bug in the application implementation.)
1021 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
1022 png_alloc_size_t size),PNG_ALLOCATED);
1024 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
1025 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
1026 /* Internal array allocator, outputs no error or warning messages on failure,
1027 * just returns NULL.
1029 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
1030 int nelements, size_t element_size),PNG_ALLOCATED);
1032 /* The same but an existing array is extended by add_elements. This function
1033 * also memsets the new elements to 0 and copies the old elements. The old
1034 * array is not freed or altered.
1036 PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
1037 png_const_voidp array, int old_elements, int add_elements,
1038 size_t element_size),PNG_ALLOCATED);
1039 #endif /* text, sPLT or unknown chunks */
1041 /* Magic to create a struct when there is no struct to call the user supplied
1042 * memory allocators. Because error handling has not been set up the memory
1043 * handlers can't safely call png_error, but this is an obscure and undocumented
1044 * restriction so libpng has to assume that the 'free' handler, at least, might
1047 PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
1048 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
1049 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
1050 png_free_ptr free_fn),PNG_ALLOCATED);
1052 /* Free memory from internal libpng struct */
1053 PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
1056 /* Free an allocated jmp_buf (always succeeds) */
1057 PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
1059 /* Function to allocate memory for zlib. PNGAPI is disallowed. */
1060 PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
1063 /* Function to free memory for zlib. PNGAPI is disallowed. */
1064 PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
1066 /* Next four functions are used internally as callbacks. PNGCBAPI is required
1067 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
1071 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
1072 png_bytep data, size_t length),PNG_EMPTY);
1074 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1075 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
1076 png_bytep buffer, size_t length),PNG_EMPTY);
1079 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
1080 png_bytep data, size_t length),PNG_EMPTY);
1082 #ifdef PNG_WRITE_FLUSH_SUPPORTED
1083 # ifdef PNG_STDIO_SUPPORTED
1084 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
1089 /* Reset the CRC variable */
1090 PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
1092 /* Write the "data" buffer to whatever output you are using */
1093 PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
1094 png_const_bytep data, size_t length),PNG_EMPTY);
1096 /* Read and check the PNG file signature */
1097 PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
1098 png_inforp info_ptr),PNG_EMPTY);
1100 /* Read the chunk header (length + type name) */
1101 PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
1104 /* Read data from whatever input you are using into the "data" buffer */
1105 PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
1106 size_t length),PNG_EMPTY);
1108 /* Read bytes into buf, and update png_ptr->crc */
1109 PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
1110 png_uint_32 length),PNG_EMPTY);
1112 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
1113 PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
1114 png_uint_32 skip),PNG_EMPTY);
1116 /* Read the CRC from the file and compare it to the libpng calculated CRC */
1117 PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
1119 /* Calculate the CRC over a section of data. Note that we are only
1120 * passing a maximum of 64K on systems that have this as a memory limit,
1121 * since this is the maximum buffer size we can specify.
1123 PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
1124 png_const_bytep ptr, size_t length),PNG_EMPTY);
1126 #ifdef PNG_WRITE_FLUSH_SUPPORTED
1127 PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
1130 /* Write various chunks */
1132 /* Write the IHDR chunk, and update the png_struct with the necessary
1135 PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
1136 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
1137 int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
1139 PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
1140 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
1142 PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
1143 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
1146 PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
1148 #ifdef PNG_WRITE_gAMA_SUPPORTED
1149 PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
1150 png_fixed_point file_gamma),PNG_EMPTY);
1153 #ifdef PNG_WRITE_sBIT_SUPPORTED
1154 PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
1155 png_const_color_8p sbit, int color_type),PNG_EMPTY);
1158 #ifdef PNG_WRITE_cHRM_SUPPORTED
1159 PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
1160 const png_xy *xy), PNG_EMPTY);
1161 /* The xy value must have been previously validated */
1164 #ifdef PNG_WRITE_sRGB_SUPPORTED
1165 PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
1166 int intent),PNG_EMPTY);
1169 #ifdef PNG_WRITE_eXIf_SUPPORTED
1170 PNG_INTERNAL_FUNCTION(void,png_write_eXIf,(png_structrp png_ptr,
1171 png_bytep exif, int num_exif),PNG_EMPTY);
1174 #ifdef PNG_WRITE_iCCP_SUPPORTED
1175 PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
1176 png_const_charp name, png_const_bytep profile), PNG_EMPTY);
1177 /* The profile must have been previously validated for correctness, the
1178 * length comes from the first four bytes. Only the base, deflate,
1179 * compression is supported.
1183 #ifdef PNG_WRITE_sPLT_SUPPORTED
1184 PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
1185 png_const_sPLT_tp palette),PNG_EMPTY);
1188 #ifdef PNG_WRITE_tRNS_SUPPORTED
1189 PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
1190 png_const_bytep trans, png_const_color_16p values, int number,
1191 int color_type),PNG_EMPTY);
1194 #ifdef PNG_WRITE_bKGD_SUPPORTED
1195 PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
1196 png_const_color_16p values, int color_type),PNG_EMPTY);
1199 #ifdef PNG_WRITE_hIST_SUPPORTED
1200 PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
1201 png_const_uint_16p hist, int num_hist),PNG_EMPTY);
1204 /* Chunks that have keywords */
1205 #ifdef PNG_WRITE_tEXt_SUPPORTED
1206 PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
1207 png_const_charp key, png_const_charp text, size_t text_len),PNG_EMPTY);
1210 #ifdef PNG_WRITE_zTXt_SUPPORTED
1211 PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
1212 key, png_const_charp text, int compression),PNG_EMPTY);
1215 #ifdef PNG_WRITE_iTXt_SUPPORTED
1216 PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
1217 int compression, png_const_charp key, png_const_charp lang,
1218 png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
1221 #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
1222 PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
1223 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
1226 #ifdef PNG_WRITE_oFFs_SUPPORTED
1227 PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
1228 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
1231 #ifdef PNG_WRITE_pCAL_SUPPORTED
1232 PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
1233 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
1234 png_const_charp units, png_charpp params),PNG_EMPTY);
1237 #ifdef PNG_WRITE_pHYs_SUPPORTED
1238 PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
1239 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
1240 int unit_type),PNG_EMPTY);
1243 #ifdef PNG_WRITE_tIME_SUPPORTED
1244 PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
1245 png_const_timep mod_time),PNG_EMPTY);
1248 #ifdef PNG_WRITE_sCAL_SUPPORTED
1249 PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
1250 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
1253 /* Called when finished processing a row of data */
1254 PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
1257 /* Internal use only. Called before first row of data */
1258 PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
1261 /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
1262 * array of png_ptr->width pixels. If the image is not interlaced or this
1263 * is the final pass this just does a memcpy, otherwise the "display" flag
1264 * is used to determine whether to copy pixels that are not in the current pass.
1266 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
1267 * function to achieve the documented 'blocky' appearance during interlaced read
1268 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
1269 * are not changed if they are not in the current pass, when display is 0.
1271 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
1273 * The API always reads from the png_struct row buffer and always assumes that
1274 * it is full width (png_do_read_interlace has already been called.)
1276 * This function is only ever used to write to row buffers provided by the
1277 * caller of the relevant libpng API and the row must have already been
1278 * transformed by the read transformations.
1280 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
1281 * bitmasks for use within the code, otherwise runtime generated masks are used.
1282 * The default is compile time masks.
1284 #ifndef PNG_USE_COMPILE_TIME_MASKS
1285 # define PNG_USE_COMPILE_TIME_MASKS 1
1287 PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
1288 png_bytep row, int display),PNG_EMPTY);
1290 #ifdef PNG_READ_INTERLACING_SUPPORTED
1291 /* Expand an interlaced row: the 'row_info' describes the pass data that has
1292 * been read in and must correspond to the pixels in 'row', the pixels are
1293 * expanded (moved apart) in 'row' to match the final layout, when doing this
1294 * the pixels are *replicated* to the intervening space. This is essential for
1295 * the correct operation of png_combine_row, above.
1297 PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
1298 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
1301 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
1303 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
1304 /* Grab pixels out of a row for an interlaced pass */
1305 PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
1306 png_bytep row, int pass),PNG_EMPTY);
1309 /* Unfilter a row: check the filter value before calling this, there is no point
1310 * calling it for PNG_FILTER_VALUE_NONE.
1312 PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
1313 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
1315 #if PNG_ARM_NEON_OPT > 0
1316 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
1317 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1318 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
1319 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1320 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
1321 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1322 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
1323 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1324 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
1325 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1326 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
1327 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1328 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
1329 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1332 #if PNG_MIPS_MSA_OPT > 0
1333 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_msa,(png_row_infop row_info,
1334 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1335 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_msa,(png_row_infop
1336 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1337 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_msa,(png_row_infop
1338 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1339 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_msa,(png_row_infop
1340 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1341 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_msa,(png_row_infop
1342 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1343 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_msa,(png_row_infop
1344 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1345 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_msa,(png_row_infop
1346 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1349 #if PNG_POWERPC_VSX_OPT > 0
1350 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_vsx,(png_row_infop row_info,
1351 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1352 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_vsx,(png_row_infop
1353 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1354 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_vsx,(png_row_infop
1355 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1356 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_vsx,(png_row_infop
1357 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1358 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_vsx,(png_row_infop
1359 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1360 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_vsx,(png_row_infop
1361 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1362 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_vsx,(png_row_infop
1363 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1366 #if PNG_INTEL_SSE_IMPLEMENTATION > 0
1367 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
1368 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1369 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
1370 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1371 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
1372 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1373 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
1374 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1375 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
1376 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1377 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
1378 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1381 /* Choose the best filter to use and filter the row data */
1382 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
1383 png_row_infop row_info),PNG_EMPTY);
1385 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1386 PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
1387 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
1388 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer
1389 * is NULL the function checks, instead, for the end of the stream. In this
1390 * case a benign error will be issued if the stream end is not found or if
1391 * extra data has to be consumed.
1393 PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
1395 /* This cleans up when the IDAT LZ stream does not end when the last image
1396 * byte is read; there is still some pending input.
1399 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
1401 /* Finish a row while reading, dealing with interlacing passes, etc. */
1402 #endif /* SEQUENTIAL_READ */
1404 /* Initialize the row buffers, etc. */
1405 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
1407 #if ZLIB_VERNUM >= 0x1240
1408 PNG_INTERNAL_FUNCTION(int,png_zlib_inflate,(png_structrp png_ptr, int flush),
1410 # define PNG_INFLATE(pp, flush) png_zlib_inflate(pp, flush)
1411 #else /* Zlib < 1.2.4 */
1412 # define PNG_INFLATE(pp, flush) inflate(&(pp)->zstream, flush)
1413 #endif /* Zlib < 1.2.4 */
1415 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1416 /* Optional call to update the users info structure */
1417 PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
1418 png_inforp info_ptr),PNG_EMPTY);
1421 /* Shared transform functions, defined in pngtran.c */
1422 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1423 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1424 PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
1425 png_bytep row, int at_start),PNG_EMPTY);
1428 #ifdef PNG_16BIT_SUPPORTED
1429 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1430 PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
1431 png_bytep row),PNG_EMPTY);
1435 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1436 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1437 PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
1438 png_bytep row),PNG_EMPTY);
1441 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1442 PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
1443 png_bytep row),PNG_EMPTY);
1446 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1447 PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
1448 png_bytep row),PNG_EMPTY);
1451 /* The following decodes the appropriate chunks, and does error correction,
1452 * then calls the appropriate callback for the chunk if it is valid.
1455 /* Decode the IHDR chunk */
1456 PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
1457 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1458 PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
1459 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1460 PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
1461 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1463 #ifdef PNG_READ_bKGD_SUPPORTED
1464 PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
1465 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1468 #ifdef PNG_READ_cHRM_SUPPORTED
1469 PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
1470 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1473 #ifdef PNG_READ_eXIf_SUPPORTED
1474 PNG_INTERNAL_FUNCTION(void,png_handle_eXIf,(png_structrp png_ptr,
1475 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1478 #ifdef PNG_READ_gAMA_SUPPORTED
1479 PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
1480 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1483 #ifdef PNG_READ_hIST_SUPPORTED
1484 PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
1485 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1488 #ifdef PNG_READ_iCCP_SUPPORTED
1489 PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
1490 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1491 #endif /* READ_iCCP */
1493 #ifdef PNG_READ_iTXt_SUPPORTED
1494 PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
1495 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1498 #ifdef PNG_READ_oFFs_SUPPORTED
1499 PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
1500 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1503 #ifdef PNG_READ_pCAL_SUPPORTED
1504 PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
1505 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1508 #ifdef PNG_READ_pHYs_SUPPORTED
1509 PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
1510 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1513 #ifdef PNG_READ_sBIT_SUPPORTED
1514 PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
1515 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1518 #ifdef PNG_READ_sCAL_SUPPORTED
1519 PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
1520 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1523 #ifdef PNG_READ_sPLT_SUPPORTED
1524 PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
1525 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1526 #endif /* READ_sPLT */
1528 #ifdef PNG_READ_sRGB_SUPPORTED
1529 PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
1530 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1533 #ifdef PNG_READ_tEXt_SUPPORTED
1534 PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
1535 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1538 #ifdef PNG_READ_tIME_SUPPORTED
1539 PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
1540 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1543 #ifdef PNG_READ_tRNS_SUPPORTED
1544 PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
1545 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1548 #ifdef PNG_READ_zTXt_SUPPORTED
1549 PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
1550 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1553 PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_const_structrp png_ptr,
1554 png_uint_32 chunk_name),PNG_EMPTY);
1556 PNG_INTERNAL_FUNCTION(void,png_check_chunk_length,(png_const_structrp png_ptr,
1557 png_uint_32 chunk_length),PNG_EMPTY);
1559 PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
1560 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
1561 /* This is the function that gets called for unknown chunks. The 'keep'
1562 * argument is either non-zero for a known chunk that has been set to be
1563 * handled as unknown or zero for an unknown chunk. By default the function
1564 * just skips the chunk or errors out if it is critical.
1567 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
1568 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
1569 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
1570 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
1571 /* Exactly as the API png_handle_as_unknown() except that the argument is a
1572 * 32-bit chunk name, not a string.
1574 #endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
1576 /* Handle the transformations for reading and writing */
1577 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1578 PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
1579 png_row_infop row_info),PNG_EMPTY);
1581 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1582 PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
1583 png_row_infop row_info),PNG_EMPTY);
1586 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1587 PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
1591 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1592 PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
1593 png_inforp info_ptr),PNG_EMPTY);
1594 PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
1595 png_inforp info_ptr),PNG_EMPTY);
1596 PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
1597 PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
1599 PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
1600 png_bytep buffer, size_t buffer_length),PNG_EMPTY);
1601 PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
1602 PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
1603 png_bytep buffer, size_t buffer_length),PNG_EMPTY);
1604 PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
1606 PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
1607 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1608 PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
1609 png_inforp info_ptr),PNG_EMPTY);
1610 PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
1611 png_inforp info_ptr),PNG_EMPTY);
1612 PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
1613 png_bytep row),PNG_EMPTY);
1614 PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
1615 png_inforp info_ptr),PNG_EMPTY);
1616 PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
1617 png_inforp info_ptr),PNG_EMPTY);
1618 PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
1620 # ifdef PNG_READ_tEXt_SUPPORTED
1621 PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
1622 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1623 PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
1624 png_inforp info_ptr),PNG_EMPTY);
1626 # ifdef PNG_READ_zTXt_SUPPORTED
1627 PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
1628 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1629 PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
1630 png_inforp info_ptr),PNG_EMPTY);
1632 # ifdef PNG_READ_iTXt_SUPPORTED
1633 PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
1634 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1635 PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
1636 png_inforp info_ptr),PNG_EMPTY);
1639 #endif /* PROGRESSIVE_READ */
1641 /* Added at libpng version 1.6.0 */
1642 #ifdef PNG_GAMMA_SUPPORTED
1643 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
1644 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
1645 /* Set the colorspace gamma with a value provided by the application or by
1646 * the gAMA chunk on read. The value will override anything set by an ICC
1650 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
1651 png_inforp info_ptr), PNG_EMPTY);
1652 /* Synchronize the info 'valid' flags with the colorspace */
1654 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
1655 png_inforp info_ptr), PNG_EMPTY);
1656 /* Copy the png_struct colorspace to the info_struct and call the above to
1657 * synchronize the flags. Checks for NULL info_ptr and does nothing.
1661 #ifdef PNG_APNG_SUPPORTED
1662 PNG_INTERNAL_FUNCTION(void,png_ensure_fcTL_is_valid,(png_structp png_ptr,
1663 png_uint_32 width, png_uint_32 height,
1664 png_uint_32 x_offset, png_uint_32 y_offset,
1665 png_uint_16 delay_num, png_uint_16 delay_den,
1666 png_byte dispose_op, png_byte blend_op), PNG_EMPTY);
1668 #ifdef PNG_READ_APNG_SUPPORTED
1669 PNG_INTERNAL_FUNCTION(void,png_handle_acTL,(png_structp png_ptr, png_infop info_ptr,
1670 png_uint_32 length),PNG_EMPTY);
1671 PNG_INTERNAL_FUNCTION(void,png_handle_fcTL,(png_structp png_ptr, png_infop info_ptr,
1672 png_uint_32 length),PNG_EMPTY);
1673 PNG_INTERNAL_FUNCTION(void,png_handle_fdAT,(png_structp png_ptr, png_infop info_ptr,
1674 png_uint_32 length),PNG_EMPTY);
1675 PNG_INTERNAL_FUNCTION(void,png_have_info,(png_structp png_ptr, png_infop info_ptr),PNG_EMPTY);
1676 PNG_INTERNAL_FUNCTION(void,png_ensure_sequence_number,(png_structp png_ptr,
1677 png_uint_32 length),PNG_EMPTY);
1678 PNG_INTERNAL_FUNCTION(void,png_read_reset,(png_structp png_ptr),PNG_EMPTY);
1679 PNG_INTERNAL_FUNCTION(void,png_read_reinit,(png_structp png_ptr,
1680 png_infop info_ptr),PNG_EMPTY);
1681 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1682 PNG_INTERNAL_FUNCTION(void,png_progressive_read_reset,(png_structp png_ptr),PNG_EMPTY);
1683 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1684 #endif /* PNG_READ_APNG_SUPPORTED */
1686 #ifdef PNG_WRITE_APNG_SUPPORTED
1687 PNG_INTERNAL_FUNCTION(void,png_write_acTL,(png_structp png_ptr,
1688 png_uint_32 num_frames, png_uint_32 num_plays),PNG_EMPTY);
1689 PNG_INTERNAL_FUNCTION(void,png_write_fcTL,(png_structp png_ptr,
1690 png_uint_32 width, png_uint_32 height,
1691 png_uint_32 x_offset, png_uint_32 y_offset,
1692 png_uint_16 delay_num, png_uint_16 delay_den,
1693 png_byte dispose_op, png_byte blend_op),PNG_EMPTY);
1694 PNG_INTERNAL_FUNCTION(void,png_write_fdAT,(png_structp png_ptr,
1695 png_const_bytep data, png_size_t length),PNG_EMPTY);
1696 PNG_INTERNAL_FUNCTION(void,png_write_reset,(png_structp png_ptr),PNG_EMPTY);
1697 PNG_INTERNAL_FUNCTION(void,png_write_reinit,(png_structp png_ptr,
1698 png_infop info_ptr, png_uint_32 width, png_uint_32 height),PNG_EMPTY);
1699 #endif /* PNG_WRITE_APNG_SUPPORTED */
1700 #endif /* PNG_APNG_SUPPORTED */
1702 /* Added at libpng version 1.4.0 */
1703 #ifdef PNG_COLORSPACE_SUPPORTED
1704 /* These internal functions are for maintaining the colorspace structure within
1705 * a png_info or png_struct (or, indeed, both).
1707 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
1708 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
1709 int preferred), PNG_EMPTY);
1711 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
1712 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
1713 int preferred), PNG_EMPTY);
1715 #ifdef PNG_sRGB_SUPPORTED
1716 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
1717 png_colorspacerp colorspace, int intent), PNG_EMPTY);
1718 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
1719 * flags to write them, if it returns false there was a problem and an error
1720 * message has already been output (but the colorspace may still need to be
1721 * synced to record the invalid flag).
1725 #ifdef PNG_iCCP_SUPPORTED
1726 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
1727 png_colorspacerp colorspace, png_const_charp name,
1728 png_uint_32 profile_length, png_const_bytep profile, int color_type),
1730 /* The 'name' is used for information only */
1732 /* Routines for checking parts of an ICC profile. */
1733 #ifdef PNG_READ_iCCP_SUPPORTED
1734 PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
1735 png_colorspacerp colorspace, png_const_charp name,
1736 png_uint_32 profile_length), PNG_EMPTY);
1737 #endif /* READ_iCCP */
1738 PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
1739 png_colorspacerp colorspace, png_const_charp name,
1740 png_uint_32 profile_length,
1741 png_const_bytep profile /* first 132 bytes only */, int color_type),
1743 PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
1744 png_colorspacerp colorspace, png_const_charp name,
1745 png_uint_32 profile_length,
1746 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
1747 #ifdef PNG_sRGB_SUPPORTED
1748 PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
1749 png_const_structrp png_ptr, png_colorspacerp colorspace,
1750 png_const_bytep profile, uLong adler), PNG_EMPTY);
1751 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
1752 * be zero to indicate that it is not available. It is used, if provided,
1753 * as a fast check on the profile when checking to see if it is sRGB.
1758 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1759 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
1760 (png_structrp png_ptr), PNG_EMPTY);
1761 /* Set the rgb_to_gray coefficients from the colorspace Y values */
1762 #endif /* READ_RGB_TO_GRAY */
1763 #endif /* COLORSPACE */
1765 /* Added at libpng version 1.4.0 */
1766 PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
1767 png_uint_32 width, png_uint_32 height, int bit_depth,
1768 int color_type, int interlace_type, int compression_type,
1769 int filter_type),PNG_EMPTY);
1771 /* Added at libpng version 1.5.10 */
1772 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
1773 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
1774 PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
1775 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
1778 #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1779 PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
1780 png_const_charp name),PNG_NORETURN);
1783 /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1784 * the end. Always leaves the buffer nul terminated. Never errors out (and
1785 * there is no error code.)
1787 PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
1788 size_t pos, png_const_charp string),PNG_EMPTY);
1790 /* Various internal functions to handle formatted warning messages, currently
1791 * only implemented for warnings.
1793 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1794 /* Utility to dump an unsigned value into a buffer, given a start pointer and
1795 * and end pointer (which should point just *beyond* the end of the buffer!)
1796 * Returns the pointer to the start of the formatted string. This utility only
1797 * does unsigned values.
1799 PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
1800 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
1802 /* Convenience macro that takes an array: */
1803 #define PNG_FORMAT_NUMBER(buffer,format,number) \
1804 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1806 /* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1807 #define PNG_NUMBER_BUFFER_SIZE 24
1809 /* These are the integer formats currently supported, the name is formed from
1810 * the standard printf(3) format string.
1812 #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1813 #define PNG_NUMBER_FORMAT_02u 2
1814 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1815 #define PNG_NUMBER_FORMAT_02d 2
1816 #define PNG_NUMBER_FORMAT_x 3
1817 #define PNG_NUMBER_FORMAT_02x 4
1818 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1821 #ifdef PNG_WARNINGS_SUPPORTED
1822 /* New defines and members adding in libpng-1.5.4 */
1823 # define PNG_WARNING_PARAMETER_SIZE 32
1824 # define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
1826 /* An l-value of this type has to be passed to the APIs below to cache the
1827 * values of the parameters to a formatted warning message.
1829 typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1830 PNG_WARNING_PARAMETER_SIZE];
1832 PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
1833 int number, png_const_charp string),PNG_EMPTY);
1834 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1835 * including the trailing '\0'.
1837 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
1838 (png_warning_parameters p, int number, int format, png_alloc_size_t value),
1840 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1841 * need to output. Use the following for a signed value.
1843 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
1844 (png_warning_parameters p, int number, int format, png_int_32 value),
1847 PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
1848 png_warning_parameters p, png_const_charp message),PNG_EMPTY);
1849 /* 'message' follows the X/Open approach of using @1, @2 to insert
1850 * parameters previously supplied using the above functions. Errors in
1851 * specifying the parameters will simply result in garbage substitutions.
1855 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
1856 /* Application errors (new in 1.6); use these functions (declared below) for
1857 * errors in the parameters or order of API function calls on read. The
1858 * 'warning' should be used for an error that can be handled completely; the
1859 * 'error' for one which can be handled safely but which may lose application
1860 * information or settings.
1862 * By default these both result in a png_error call prior to release, while in a
1863 * released version the 'warning' is just a warning. However if the application
1864 * explicitly disables benign errors (explicitly permitting the code to lose
1865 * information) they both turn into warnings.
1867 * If benign errors aren't supported they end up as the corresponding base call
1868 * (png_warning or png_error.)
1870 PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
1871 png_const_charp message),PNG_EMPTY);
1872 /* The application provided invalid parameters to an API function or called
1873 * an API function at the wrong time, libpng can completely recover.
1876 PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
1877 png_const_charp message),PNG_EMPTY);
1878 /* As above but libpng will ignore the call, or attempt some other partial
1879 * recovery from the error.
1882 # define png_app_warning(pp,s) png_warning(pp,s)
1883 # define png_app_error(pp,s) png_error(pp,s)
1886 PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
1887 png_const_charp message, int error),PNG_EMPTY);
1888 /* Report a recoverable issue in chunk data. On read this is used to report
1889 * a problem found while reading a particular chunk and the
1890 * png_chunk_benign_error or png_chunk_warning function is used as
1891 * appropriate. On write this is used to report an error that comes from
1892 * data set via an application call to a png_set_ API and png_app_error or
1893 * png_app_warning is used as appropriate.
1895 * The 'error' parameter must have one of the following values:
1897 #define PNG_CHUNK_WARNING 0 /* never an error */
1898 #define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
1899 #define PNG_CHUNK_ERROR 2 /* always an error */
1901 /* ASCII to FP interfaces, currently only implemented if sCAL
1902 * support is required.
1904 #if defined(PNG_sCAL_SUPPORTED)
1905 /* MAX_DIGITS is actually the maximum number of characters in an sCAL
1906 * width or height, derived from the precision (number of significant
1907 * digits - a build time settable option) and assumptions about the
1908 * maximum ridiculous exponent.
1910 #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1912 #ifdef PNG_FLOATING_POINT_SUPPORTED
1913 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
1914 png_charp ascii, size_t size, double fp, unsigned int precision),
1916 #endif /* FLOATING_POINT */
1918 #ifdef PNG_FIXED_POINT_SUPPORTED
1919 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
1920 png_charp ascii, size_t size, png_fixed_point fp),PNG_EMPTY);
1921 #endif /* FIXED_POINT */
1924 #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1925 /* An internal API to validate the format of a floating point number.
1926 * The result is the index of the next character. If the number is
1927 * not valid it will be the index of a character in the supposed number.
1929 * The format of a number is defined in the PNG extensions specification
1930 * and this API is strictly conformant to that spec, not anyone elses!
1932 * The format as a regular expression is:
1934 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1938 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1940 * The complexity is that either integer or fraction must be present and the
1941 * fraction is permitted to have no digits only if the integer is present.
1943 * NOTE: The dangling E problem.
1944 * There is a PNG valid floating point number in the following:
1946 * PNG floating point numbers are not greedy.
1948 * Working this out requires *TWO* character lookahead (because of the
1949 * sign), the parser does not do this - it will fail at the 'r' - this
1950 * doesn't matter for PNG sCAL chunk values, but it requires more care
1951 * if the value were ever to be embedded in something more complex. Use
1952 * ANSI-C strtod if you need the lookahead.
1954 /* State table for the parser. */
1955 #define PNG_FP_INTEGER 0 /* before or in integer */
1956 #define PNG_FP_FRACTION 1 /* before or in fraction */
1957 #define PNG_FP_EXPONENT 2 /* before or in exponent */
1958 #define PNG_FP_STATE 3 /* mask for the above */
1959 #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1960 #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1961 #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1962 #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1963 #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1965 /* These three values don't affect the parser. They are set but not used.
1967 #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1968 #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1969 #define PNG_FP_NONZERO 256 /* A non-zero value */
1970 #define PNG_FP_STICKY 448 /* The above three flags */
1972 /* This is available for the caller to store in 'state' if required. Do not
1973 * call the parser after setting it (the parser sometimes clears it.)
1975 #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1977 /* Result codes for the parser (boolean - true meants ok, false means
1980 #define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1981 #define PNG_FP_OK 1 /* The number is valid */
1983 /* Tests on the sticky non-zero and negative flags. To pass these checks
1984 * the state must also indicate that the whole number is valid - this is
1985 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1986 * is equivalent to PNG_FP_OK above.)
1988 #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1989 /* NZ_MASK: the string is valid and a non-zero negative value */
1990 #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
1991 /* Z MASK: the string is valid and a non-zero value. */
1992 /* PNG_FP_SAW_DIGIT: the string is valid. */
1993 #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
1994 #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
1995 #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
1997 /* The actual parser. This can be called repeatedly. It updates
1998 * the index into the string and the state variable (which must
1999 * be initialized to 0). It returns a result code, as above. There
2000 * is no point calling the parser any more if it fails to advance to
2001 * the end of the string - it is stuck on an invalid character (or
2002 * terminated by '\0').
2004 * Note that the pointer will consume an E or even an E+ and then leave
2005 * a 'maybe' state even though a preceding integer.fraction is valid.
2006 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
2007 * a valid number. It's possible to recover from this by calling
2008 * the parser again (from the start, with state 0) but with a string
2009 * that omits the last character (i.e. set the size to the index of
2010 * the problem character.) This has not been tested within libpng.
2012 PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
2013 size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
2015 /* This is the same but it checks a complete string and returns true
2016 * only if it just contains a floating point number. As of 1.5.4 this
2017 * function also returns the state at the end of parsing the number if
2018 * it was valid (otherwise it returns 0.) This can be used for testing
2019 * for negative or zero values using the sticky flag.
2021 PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
2022 size_t size),PNG_EMPTY);
2023 #endif /* pCAL || sCAL */
2025 #if defined(PNG_GAMMA_SUPPORTED) ||\
2026 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
2027 /* Added at libpng version 1.5.0 */
2028 /* This is a utility to provide a*times/div (rounded) and indicate
2029 * if there is an overflow. The result is a boolean - false (0)
2030 * for overflow, true (1) if no overflow, in which case *res
2033 PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
2034 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
2037 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
2038 /* Same deal, but issue a warning on overflow and return 0. */
2039 PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
2040 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
2041 png_int_32 divided_by),PNG_EMPTY);
2044 #ifdef PNG_GAMMA_SUPPORTED
2045 /* Calculate a reciprocal - used for gamma values. This returns
2046 * 0 if the argument is 0 in order to maintain an undefined value;
2047 * there are no warnings.
2049 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
2052 #ifdef PNG_READ_GAMMA_SUPPORTED
2053 /* The same but gives a reciprocal of the product of two fixed point
2054 * values. Accuracy is suitable for gamma calculations but this is
2055 * not exact - use png_muldiv for that. Only required at present on read.
2057 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
2058 png_fixed_point b),PNG_EMPTY);
2061 /* Return true if the gamma value is significantly different from 1.0 */
2062 PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
2066 #ifdef PNG_READ_GAMMA_SUPPORTED
2067 /* Internal fixed point gamma correction. These APIs are called as
2068 * required to convert single values - they don't need to be fast,
2069 * they are not used when processing image pixel values.
2071 * While the input is an 'unsigned' value it must actually be the
2072 * correct bit value - 0..255 or 0..65535 as required.
2074 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
2075 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
2076 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
2077 png_fixed_point gamma_value),PNG_EMPTY);
2078 PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
2079 png_fixed_point gamma_value),PNG_EMPTY);
2080 PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
2082 PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
2083 int bit_depth),PNG_EMPTY);
2086 /* SIMPLIFIED READ/WRITE SUPPORT */
2087 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
2088 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
2089 /* The internal structure that png_image::opaque points to. */
2090 typedef struct png_control
2092 png_structp png_ptr;
2094 png_voidp error_buf; /* Always a jmp_buf at present. */
2096 png_const_bytep memory; /* Memory buffer. */
2097 size_t size; /* Size of the memory buffer. */
2099 unsigned int for_write :1; /* Otherwise it is a read structure */
2100 unsigned int owned_file :1; /* We own the file in io_ptr */
2103 /* Return the pointer to the jmp_buf from a png_control: necessary because C
2104 * does not reveal the type of the elements of jmp_buf.
2107 # define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
2109 # define png_control_jmp_buf(pc) ((pc)->error_buf)
2112 /* Utility to safely execute a piece of libpng code catching and logging any
2113 * errors that might occur. Returns true on success, false on failure (either
2114 * of the function or as a result of a png_error.)
2116 PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr,
2117 png_const_charp error_message),PNG_NORETURN);
2119 #ifdef PNG_WARNINGS_SUPPORTED
2120 PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr,
2121 png_const_charp warning_message),PNG_EMPTY);
2123 # define png_safe_warning 0/*dummy argument*/
2126 PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
2127 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
2129 /* Utility to log an error; this also cleans up the png_image; the function
2130 * always returns 0 (false).
2132 PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
2133 png_const_charp error_message),PNG_EMPTY);
2135 #ifndef PNG_SIMPLIFIED_READ_SUPPORTED
2136 /* png_image_free is used by the write code but not exported */
2137 PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
2138 #endif /* !SIMPLIFIED_READ */
2140 #endif /* SIMPLIFIED READ/WRITE */
2142 /* These are initialization functions for hardware specific PNG filter
2143 * optimizations; list these here then select the appropriate one at compile
2144 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
2145 * the generic code is used.
2147 #ifdef PNG_FILTER_OPTIMIZATIONS
2148 PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
2149 unsigned int bpp), PNG_EMPTY);
2150 /* Just declare the optimization that will be used */
2152 /* List *all* the possible optimizations here - this branch is required if
2153 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
2154 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
2156 # if PNG_ARM_NEON_OPT > 0
2157 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
2158 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2161 #if PNG_MIPS_MSA_OPT > 0
2162 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_msa,
2163 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2166 # if PNG_INTEL_SSE_IMPLEMENTATION > 0
2167 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
2168 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2172 PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
2173 png_const_charp key, png_bytep new_key), PNG_EMPTY);
2175 #if PNG_ARM_NEON_IMPLEMENTATION == 1
2176 PNG_INTERNAL_FUNCTION(void,
2177 png_riffle_palette_neon,
2180 PNG_INTERNAL_FUNCTION(int,
2181 png_do_expand_palette_rgba8_neon,
2188 PNG_INTERNAL_FUNCTION(int,
2189 png_do_expand_palette_rgb8_neon,
2198 /* Maintainer: Put new private prototypes here ^ */
2200 #include "pngdebug.h"
2206 #endif /* PNG_VERSION_INFO_ONLY */
2207 #endif /* PNGPRIV_H */
projects / platform / upstream / libpng.git / blob