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source: vbox/trunk/src/libs/libpng-1.6.42/pngpriv.h

Last change on this file was 103316, checked in by vboxsync, 3 months ago

libpng-1.6.42: Applied and adjusted our libpng changes to 1.6.42. bugref:8515
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1
2/* pngpriv.h - private declarations for use inside libpng
3 *
4 * Copyright (c) 2018-2024 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.
8 *
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
12 */
13
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.
21 */
22
23#ifndef PNGPRIV_H
24#define PNGPRIV_H
25
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.
29 *
30 * Feature Test Macros must be defined before any system header is included (see
31 * POSIX 1003.1 2.8.2 "POSIX Symbols."
32 *
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.)
37 */
38#ifndef _POSIX_SOURCE
39# define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
40#endif
41
42#ifndef PNG_VERSION_INFO_ONLY
43/* Standard library headers not required by png.h: */
44# include <stdlib.h>
45# include <string.h>
46#endif
47
48#define PNGLIB_BUILD /*libpng is being built, not used*/
49
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.
58 */
59#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
60# include <config.h>
61
62 /* Pick up the definition of 'restrict' from config.h if it was read: */
63# define PNG_RESTRICT restrict
64#endif
65
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.
70 */
71#ifndef PNGLCONF_H
72# include "pnglibconf.h"
73#endif
74
75/* Local renames may change non-exported API functions from png.h */
76#if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
77# include "pngprefix.h"
78#endif
79
80#ifdef PNG_USER_CONFIG
81# include "pngusr.h"
82 /* These should have been defined in pngusr.h */
83# ifndef PNG_USER_PRIVATEBUILD
84# define PNG_USER_PRIVATEBUILD "Custom libpng build"
85# endif
86# ifndef PNG_USER_DLLFNAME_POSTFIX
87# define PNG_USER_DLLFNAME_POSTFIX "Cb"
88# endif
89#endif
90
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.)
100 *
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
108 * do this.
109 */
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.
116 *
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
121 * off.
122 *
123 * Note that gcc-4.9 defines __ARM_NEON instead of the deprecated
124 * __ARM_NEON__, so we check both variants.
125 *
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.
129 */
130# if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \
131 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
132# define PNG_ARM_NEON_OPT 2
133# else
134# define PNG_ARM_NEON_OPT 0
135# endif
136#endif
137
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.
141 */
142# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
143
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
147 * be:
148 *
149 * 1 The intrinsics code (the default with __ARM_NEON__)
150 * 2 The hand coded assembler (the default without __ARM_NEON__)
151 *
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.
157 */
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.)
165 */
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
169 */
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:
176 */
177# if !defined(__aarch64__) && !defined(_M_ARM64)
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 */
183
184# ifndef PNG_ARM_NEON_IMPLEMENTATION
185 /* Use the intrinsics code by default. */
186# define PNG_ARM_NEON_IMPLEMENTATION 1
187# endif
188#else /* PNG_ARM_NEON_OPT == 0 */
189# define PNG_ARM_NEON_IMPLEMENTATION 0
190#endif /* PNG_ARM_NEON_OPT > 0 */
191
192#ifndef PNG_MIPS_MSA_OPT
193# if defined(__mips_msa) && (__mips_isa_rev >= 5) && \
194 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
195# define PNG_MIPS_MSA_OPT 2
196# else
197# define PNG_MIPS_MSA_OPT 0
198# endif
199#endif
200
201#ifndef PNG_MIPS_MMI_OPT
202# ifdef PNG_MIPS_MMI
203# if defined(__mips_loongson_mmi) && (_MIPS_SIM == _ABI64) && \
204 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
205# define PNG_MIPS_MMI_OPT 1
206# else
207# define PNG_MIPS_MMI_OPT 0
208# endif
209# else
210# define PNG_MIPS_MMI_OPT 0
211# endif
212#endif
213
214#ifndef PNG_POWERPC_VSX_OPT
215# if defined(__PPC64__) && defined(__ALTIVEC__) && defined(__VSX__)
216# define PNG_POWERPC_VSX_OPT 2
217# else
218# define PNG_POWERPC_VSX_OPT 0
219# endif
220#endif
221
222#ifndef PNG_LOONGARCH_LSX_OPT
223# if defined(__loongarch_sx)
224# define PNG_LOONGARCH_LSX_OPT 1
225# else
226# define PNG_LOONGARCH_LSX_OPT 0
227# endif
228#endif
229
230#ifndef PNG_INTEL_SSE_OPT
231# ifdef PNG_INTEL_SSE
232 /* Only check for SSE if the build configuration has been modified to
233 * enable SSE optimizations. This means that these optimizations will
234 * be off by default. See contrib/intel for more details.
235 */
236# if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
237 defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
238 (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
239# define PNG_INTEL_SSE_OPT 1
240# else
241# define PNG_INTEL_SSE_OPT 0
242# endif
243# else
244# define PNG_INTEL_SSE_OPT 0
245# endif
246#endif
247
248#if PNG_INTEL_SSE_OPT > 0
249# ifndef PNG_INTEL_SSE_IMPLEMENTATION
250# if defined(__SSE4_1__) || defined(__AVX__)
251 /* We are not actually using AVX, but checking for AVX is the best
252 way we can detect SSE4.1 and SSSE3 on MSVC.
253 */
254# define PNG_INTEL_SSE_IMPLEMENTATION 3
255# elif defined(__SSSE3__)
256# define PNG_INTEL_SSE_IMPLEMENTATION 2
257# elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
258 (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
259# define PNG_INTEL_SSE_IMPLEMENTATION 1
260# else
261# define PNG_INTEL_SSE_IMPLEMENTATION 0
262# endif
263# endif
264
265# if PNG_INTEL_SSE_IMPLEMENTATION > 0
266# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
267# endif
268#else
269# define PNG_INTEL_SSE_IMPLEMENTATION 0
270#endif
271
272#if PNG_MIPS_MSA_OPT > 0
273# ifndef PNG_MIPS_MSA_IMPLEMENTATION
274# if defined(__mips_msa)
275# if defined(__clang__)
276# elif defined(__GNUC__)
277# if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
278# define PNG_MIPS_MSA_IMPLEMENTATION 2
279# endif /* no GNUC support */
280# endif /* __GNUC__ */
281# else /* !defined __mips_msa */
282# define PNG_MIPS_MSA_IMPLEMENTATION 2
283# endif /* __mips_msa */
284# endif /* !PNG_MIPS_MSA_IMPLEMENTATION */
285
286# ifndef PNG_MIPS_MSA_IMPLEMENTATION
287# define PNG_MIPS_MSA_IMPLEMENTATION 1
288# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_mips
289# endif
290#else
291# define PNG_MIPS_MSA_IMPLEMENTATION 0
292#endif /* PNG_MIPS_MSA_OPT > 0 */
293
294#if PNG_MIPS_MMI_OPT > 0
295# ifndef PNG_MIPS_MMI_IMPLEMENTATION
296# if defined(__mips_loongson_mmi) && (_MIPS_SIM == _ABI64)
297# define PNG_MIPS_MMI_IMPLEMENTATION 2
298# else /* !defined __mips_loongson_mmi || _MIPS_SIM != _ABI64 */
299# define PNG_MIPS_MMI_IMPLEMENTATION 0
300# endif /* __mips_loongson_mmi && _MIPS_SIM == _ABI64 */
301# endif /* !PNG_MIPS_MMI_IMPLEMENTATION */
302
303# if PNG_MIPS_MMI_IMPLEMENTATION > 0
304# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_mips
305# endif
306#else
307# define PNG_MIPS_MMI_IMPLEMENTATION 0
308#endif /* PNG_MIPS_MMI_OPT > 0 */
309
310#if PNG_POWERPC_VSX_OPT > 0
311# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
312# define PNG_POWERPC_VSX_IMPLEMENTATION 1
313#else
314# define PNG_POWERPC_VSX_IMPLEMENTATION 0
315#endif
316
317#if PNG_LOONGARCH_LSX_OPT > 0
318# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_lsx
319# define PNG_LOONGARCH_LSX_IMPLEMENTATION 1
320#else
321# define PNG_LOONGARCH_LSX_IMPLEMENTATION 0
322#endif
323
324/* Is this a build of a DLL where compilation of the object modules requires
325 * different preprocessor settings to those required for a simple library? If
326 * so PNG_BUILD_DLL must be set.
327 *
328 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
329 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
330 * static library of libpng then link the DLL against that.
331 */
332#ifndef PNG_BUILD_DLL
333# ifdef DLL_EXPORT
334 /* This is set by libtool when files are compiled for a DLL; libtool
335 * always compiles twice, even on systems where it isn't necessary. Set
336 * PNG_BUILD_DLL in case it is necessary:
337 */
338# define PNG_BUILD_DLL
339# else
340# ifdef _WINDLL
341 /* This is set by the Microsoft Visual Studio IDE in projects that
342 * build a DLL. It can't easily be removed from those projects (it
343 * isn't visible in the Visual Studio UI) so it is a fairly reliable
344 * indication that PNG_IMPEXP needs to be set to the DLL export
345 * attributes.
346 */
347# define PNG_BUILD_DLL
348# else
349# ifdef __DLL__
350 /* This is set by the Borland C system when compiling for a DLL
351 * (as above.)
352 */
353# define PNG_BUILD_DLL
354# else
355 /* Add additional compiler cases here. */
356# endif
357# endif
358# endif
359#endif /* Setting PNG_BUILD_DLL if required */
360
361/* See pngconf.h for more details: the builder of the library may set this on
362 * the command line to the right thing for the specific compilation system or it
363 * may be automagically set above (at present we know of no system where it does
364 * need to be set on the command line.)
365 *
366 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
367 * setting it to the "import" setting for a DLL build.
368 */
369#ifndef PNG_IMPEXP
370# ifdef PNG_BUILD_DLL
371# define PNG_IMPEXP PNG_DLL_EXPORT
372# else
373 /* Not building a DLL, or the DLL doesn't require specific export
374 * definitions.
375 */
376# define PNG_IMPEXP
377# endif
378#endif
379
380/* No warnings for private or deprecated functions in the build: */
381#ifndef PNG_DEPRECATED
382# define PNG_DEPRECATED
383#endif
384#ifndef PNG_PRIVATE
385# define PNG_PRIVATE
386#endif
387
388/* Symbol preprocessing support.
389 *
390 * To enable listing global, but internal, symbols the following macros should
391 * always be used to declare an extern data or function object in this file.
392 */
393#ifndef PNG_INTERNAL_DATA
394# define PNG_INTERNAL_DATA(type, name, array) PNG_LINKAGE_DATA type name array
395#endif
396
397#ifndef PNG_INTERNAL_FUNCTION
398# define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
399 PNG_LINKAGE_FUNCTION PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
400#endif
401
402#ifndef PNG_INTERNAL_CALLBACK
403# define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
404 PNG_LINKAGE_CALLBACK PNG_FUNCTION(type, (PNGCBAPI name), args,\
405 PNG_EMPTY attributes)
406#endif
407
408/* If floating or fixed point APIs are disabled they may still be compiled
409 * internally. To handle this make sure they are declared as the appropriate
410 * internal extern function (otherwise the symbol prefixing stuff won't work and
411 * the functions will be used without definitions.)
412 *
413 * NOTE: although all the API functions are declared here they are not all
414 * actually built! Because the declarations are still made it is necessary to
415 * fake out types that they depend on.
416 */
417#ifndef PNG_FP_EXPORT
418# ifndef PNG_FLOATING_POINT_SUPPORTED
419# define PNG_FP_EXPORT(ordinal, type, name, args)\
420 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
421# ifndef PNG_VERSION_INFO_ONLY
422 typedef struct png_incomplete png_double;
423 typedef png_double* png_doublep;
424 typedef const png_double* png_const_doublep;
425 typedef png_double** png_doublepp;
426# endif
427# endif
428#endif
429#ifndef PNG_FIXED_EXPORT
430# ifndef PNG_FIXED_POINT_SUPPORTED
431# define PNG_FIXED_EXPORT(ordinal, type, name, args)\
432 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
433# endif
434#endif
435
436#include "png.h"
437
438/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
439#ifndef PNG_DLL_EXPORT
440# define PNG_DLL_EXPORT
441#endif
442
443/* This is a global switch to set the compilation for an installed system
444 * (a release build). It can be set for testing debug builds to ensure that
445 * they will compile when the build type is switched to RC or STABLE, the
446 * default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS
447 * with either:
448 *
449 * -DPNG_RELEASE_BUILD Turns on the release compile path
450 * -DPNG_RELEASE_BUILD=0 Turns it off
451 * or in your pngusr.h with
452 * #define PNG_RELEASE_BUILD=1 Turns on the release compile path
453 * #define PNG_RELEASE_BUILD=0 Turns it off
454 */
455#ifndef PNG_RELEASE_BUILD
456# define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC)
457#endif
458
459/* SECURITY and SAFETY:
460 *
461 * libpng is built with support for internal limits on image dimensions and
462 * memory usage. These are documented in scripts/pnglibconf.dfa of the
463 * source and recorded in the machine generated header file pnglibconf.h.
464 */
465
466/* If you are running on a machine where you cannot allocate more
467 * than 64K of memory at once, uncomment this. While libpng will not
468 * normally need that much memory in a chunk (unless you load up a very
469 * large file), zlib needs to know how big of a chunk it can use, and
470 * libpng thus makes sure to check any memory allocation to verify it
471 * will fit into memory.
472 *
473 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
474 * same limit and pngconf.h (already included) sets the limit
475 * if certain operating systems are detected.
476 */
477#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
478# define PNG_MAX_MALLOC_64K
479#endif
480
481#ifndef PNG_UNUSED
482/* Unused formal parameter warnings are silenced using the following macro
483 * which is expected to have no bad effects on performance (optimizing
484 * compilers will probably remove it entirely). Note that if you replace
485 * it with something other than whitespace, you must include the terminating
486 * semicolon.
487 */
488# define PNG_UNUSED(param) (void)param;
489#endif
490
491/* Just a little check that someone hasn't tried to define something
492 * contradictory.
493 */
494#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
495# undef PNG_ZBUF_SIZE
496# define PNG_ZBUF_SIZE 65536L
497#endif
498
499/* If warnings or errors are turned off the code is disabled or redirected here.
500 * From 1.5.4 functions have been added to allow very limited formatting of
501 * error and warning messages - this code will also be disabled here.
502 */
503#ifdef PNG_WARNINGS_SUPPORTED
504# define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
505#else
506# define png_warning_parameter(p,number,string) ((void)0)
507# define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
508# define png_warning_parameter_signed(p,number,format,value) ((void)0)
509# define png_formatted_warning(pp,p,message) ((void)(pp))
510# define PNG_WARNING_PARAMETERS(p)
511#endif
512#ifndef PNG_ERROR_TEXT_SUPPORTED
513# define png_fixed_error(s1,s2) png_err(s1)
514#endif
515
516/* Some fixed point APIs are still required even if not exported because
517 * they get used by the corresponding floating point APIs. This magic
518 * deals with this:
519 */
520#ifdef PNG_FIXED_POINT_SUPPORTED
521# define PNGFAPI PNGAPI
522#else
523# define PNGFAPI /* PRIVATE */
524#endif
525
526#ifndef PNG_VERSION_INFO_ONLY
527/* Other defines specific to compilers can go here. Try to keep
528 * them inside an appropriate ifdef/endif pair for portability.
529 */
530
531/* C allows up-casts from (void*) to any pointer and (const void*) to any
532 * pointer to a const object. C++ regards this as a type error and requires an
533 * explicit, static, cast and provides the static_cast<> rune to ensure that
534 * const is not cast away.
535 */
536#ifdef __cplusplus
537# define png_voidcast(type, value) static_cast<type>(value)
538# define png_constcast(type, value) const_cast<type>(value)
539# define png_aligncast(type, value) \
540 static_cast<type>(static_cast<void*>(value))
541# define png_aligncastconst(type, value) \
542 static_cast<type>(static_cast<const void*>(value))
543#else
544# define png_voidcast(type, value) (value)
545# define png_constcast(type, value) ((type)(void*)(const void*)(value))
546# define png_aligncast(type, value) ((void*)(value))
547# define png_aligncastconst(type, value) ((const void*)(value))
548#endif /* __cplusplus */
549
550#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
551 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
552 /* png.c requires the following ANSI-C constants if the conversion of
553 * floating point to ASCII is implemented therein:
554 *
555 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
556 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
557 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
558 */
559# include <float.h>
560
561# include <math.h>
562
563# if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
564 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
565 * MATH=68881
566 */
567# include <m68881.h>
568# endif
569#endif
570
571/* This provides the non-ANSI (far) memory allocation routines. */
572#if defined(__TURBOC__) && defined(__MSDOS__)
573# include <mem.h>
574# include <alloc.h>
575#endif
576
577#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
578 defined(_WIN32) || defined(__WIN32__)
579# ifdef VBOX
580# include <iprt/win/windows.h> /* defines _WINDOWS_ macro */
581# else
582# include <windows.h> /* defines _WINDOWS_ macro */
583# endif
584#endif
585#endif /* PNG_VERSION_INFO_ONLY */
586
587/* Moved here around 1.5.0beta36 from pngconf.h */
588/* Users may want to use these so they are not private. Any library
589 * functions that are passed far data must be model-independent.
590 */
591
592/* Platform-independent functions */
593#ifndef PNG_ABORT
594# define PNG_ABORT() abort()
595#endif
596
597/* These macros may need to be architecture dependent. */
598#define PNG_ALIGN_NONE 0 /* do not use data alignment */
599#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
600#ifdef offsetof
601# define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
602#else
603# define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
604#endif
605#define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
606
607#ifndef PNG_ALIGN_TYPE
608 /* Default to using aligned access optimizations and requiring alignment to a
609 * multiple of the data type size. Override in a compiler specific fashion
610 * if necessary by inserting tests here:
611 */
612# define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
613#endif
614
615#if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
616 /* This is used because in some compiler implementations non-aligned
617 * structure members are supported, so the offsetof approach below fails.
618 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
619 * is good for performance. Do not do this unless you have tested the
620 * result and understand it.
621 */
622# define png_alignof(type) (sizeof(type))
623#else
624# if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
625# define png_alignof(type) offsetof(struct{char c; type t;}, t)
626# else
627# if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
628# define png_alignof(type) 1
629# endif
630 /* Else leave png_alignof undefined to prevent use thereof */
631# endif
632#endif
633
634/* This implicitly assumes alignment is always a multiple of 2. */
635#ifdef png_alignof
636# define png_isaligned(ptr, type) \
637 (((type)(size_t)((const void*)(ptr)) & (type)(png_alignof(type)-1)) == 0)
638#else
639# define png_isaligned(ptr, type) 0
640#endif
641
642/* End of memory model/platform independent support */
643/* End of 1.5.0beta36 move from pngconf.h */
644
645/* CONSTANTS and UTILITY MACROS
646 * These are used internally by libpng and not exposed in the API
647 */
648
649/* Various modes of operation. Note that after an init, mode is set to
650 * zero automatically when the structure is created. Three of these
651 * are defined in png.h because they need to be visible to applications
652 * that call png_set_unknown_chunk().
653 */
654/* #define PNG_HAVE_IHDR 0x01U (defined in png.h) */
655/* #define PNG_HAVE_PLTE 0x02U (defined in png.h) */
656#define PNG_HAVE_IDAT 0x04U
657/* #define PNG_AFTER_IDAT 0x08U (defined in png.h) */
658#define PNG_HAVE_IEND 0x10U
659 /* 0x20U (unused) */
660 /* 0x40U (unused) */
661 /* 0x80U (unused) */
662#define PNG_HAVE_CHUNK_HEADER 0x100U
663#define PNG_WROTE_tIME 0x200U
664#define PNG_WROTE_INFO_BEFORE_PLTE 0x400U
665#define PNG_BACKGROUND_IS_GRAY 0x800U
666#define PNG_HAVE_PNG_SIGNATURE 0x1000U
667#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000U /* Have another chunk after IDAT */
668#define PNG_WROTE_eXIf 0x4000U
669#define PNG_IS_READ_STRUCT 0x8000U /* Else is a write struct */
670
671/* Flags for the transformations the PNG library does on the image data */
672#define PNG_BGR 0x0001U
673#define PNG_INTERLACE 0x0002U
674#define PNG_PACK 0x0004U
675#define PNG_SHIFT 0x0008U
676#define PNG_SWAP_BYTES 0x0010U
677#define PNG_INVERT_MONO 0x0020U
678#define PNG_QUANTIZE 0x0040U
679#define PNG_COMPOSE 0x0080U /* Was PNG_BACKGROUND */
680#define PNG_BACKGROUND_EXPAND 0x0100U
681#define PNG_EXPAND_16 0x0200U /* Added to libpng 1.5.2 */
682#define PNG_16_TO_8 0x0400U /* Becomes 'chop' in 1.5.4 */
683#define PNG_RGBA 0x0800U
684#define PNG_EXPAND 0x1000U
685#define PNG_GAMMA 0x2000U
686#define PNG_GRAY_TO_RGB 0x4000U
687#define PNG_FILLER 0x8000U
688#define PNG_PACKSWAP 0x10000U
689#define PNG_SWAP_ALPHA 0x20000U
690#define PNG_STRIP_ALPHA 0x40000U
691#define PNG_INVERT_ALPHA 0x80000U
692#define PNG_USER_TRANSFORM 0x100000U
693#define PNG_RGB_TO_GRAY_ERR 0x200000U
694#define PNG_RGB_TO_GRAY_WARN 0x400000U
695#define PNG_RGB_TO_GRAY 0x600000U /* two bits, RGB_TO_GRAY_ERR|WARN */
696#define PNG_ENCODE_ALPHA 0x800000U /* Added to libpng-1.5.4 */
697#define PNG_ADD_ALPHA 0x1000000U /* Added to libpng-1.2.7 */
698#define PNG_EXPAND_tRNS 0x2000000U /* Added to libpng-1.2.9 */
699#define PNG_SCALE_16_TO_8 0x4000000U /* Added to libpng-1.5.4 */
700 /* 0x8000000U unused */
701 /* 0x10000000U unused */
702 /* 0x20000000U unused */
703 /* 0x40000000U unused */
704/* Flags for png_create_struct */
705#define PNG_STRUCT_PNG 0x0001U
706#define PNG_STRUCT_INFO 0x0002U
707
708/* Flags for the png_ptr->flags rather than declaring a byte for each one */
709#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001U
710#define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002U /* Added to libpng-1.6.0 */
711 /* 0x0004U unused */
712#define PNG_FLAG_ZSTREAM_ENDED 0x0008U /* Added to libpng-1.6.0 */
713 /* 0x0010U unused */
714 /* 0x0020U unused */
715#define PNG_FLAG_ROW_INIT 0x0040U
716#define PNG_FLAG_FILLER_AFTER 0x0080U
717#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100U
718#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200U
719#define PNG_FLAG_CRC_CRITICAL_USE 0x0400U
720#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800U
721#define PNG_FLAG_ASSUME_sRGB 0x1000U /* Added to libpng-1.5.4 */
722#define PNG_FLAG_OPTIMIZE_ALPHA 0x2000U /* Added to libpng-1.5.4 */
723#define PNG_FLAG_DETECT_UNINITIALIZED 0x4000U /* Added to libpng-1.5.4 */
724/* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000U */
725/* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000U */
726#define PNG_FLAG_LIBRARY_MISMATCH 0x20000U
727#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000U
728#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000U
729#define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000U /* Added to libpng-1.4.0 */
730#define PNG_FLAG_APP_WARNINGS_WARN 0x200000U /* Added to libpng-1.6.0 */
731#define PNG_FLAG_APP_ERRORS_WARN 0x400000U /* Added to libpng-1.6.0 */
732 /* 0x800000U unused */
733 /* 0x1000000U unused */
734 /* 0x2000000U unused */
735 /* 0x4000000U unused */
736 /* 0x8000000U unused */
737 /* 0x10000000U unused */
738 /* 0x20000000U unused */
739 /* 0x40000000U unused */
740
741#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
742 PNG_FLAG_CRC_ANCILLARY_NOWARN)
743
744#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
745 PNG_FLAG_CRC_CRITICAL_IGNORE)
746
747#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
748 PNG_FLAG_CRC_CRITICAL_MASK)
749
750/* Save typing and make code easier to understand */
751
752#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
753 abs((int)((c1).green) - (int)((c2).green)) + \
754 abs((int)((c1).blue) - (int)((c2).blue)))
755
756/* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
757 * by dividing by 257 *with rounding*. This macro is exact for the given range.
758 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the
759 * macro were established by experiment (modifying the added value). The macro
760 * has a second variant that takes a value already scaled by 255 and divides by
761 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it
762 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
763 */
764#define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
765#define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
766
767/* Added to libpng-1.2.6 JB */
768#define PNG_ROWBYTES(pixel_bits, width) \
769 ((pixel_bits) >= 8 ? \
770 ((size_t)(width) * (((size_t)(pixel_bits)) >> 3)) : \
771 (( ((size_t)(width) * ((size_t)(pixel_bits))) + 7) >> 3) )
772
773/* This returns the number of trailing bits in the last byte of a row, 0 if the
774 * last byte is completely full of pixels. It is, in principle, (pixel_bits x
775 * width) % 8, but that would overflow for large 'width'. The second macro is
776 * the same except that it returns the number of unused bits in the last byte;
777 * (8-TRAILBITS), but 0 when TRAILBITS is 0.
778 *
779 * NOTE: these macros are intended to be self-evidently correct and never
780 * overflow on the assumption that pixel_bits is in the range 0..255. The
781 * arguments are evaluated only once and they can be signed (e.g. as a result of
782 * the integral promotions). The result of the expression always has type
783 * (png_uint_32), however the compiler always knows it is in the range 0..7.
784 */
785#define PNG_TRAILBITS(pixel_bits, width) \
786 (((pixel_bits) * ((width) % (png_uint_32)8)) % 8)
787
788#define PNG_PADBITS(pixel_bits, width) \
789 ((8 - PNG_TRAILBITS(pixel_bits, width)) % 8)
790
791/* PNG_OUT_OF_RANGE returns true if value is outside the range
792 * ideal-delta..ideal+delta. Each argument is evaluated twice.
793 * "ideal" and "delta" should be constants, normally simple
794 * integers, "value" a variable. Added to libpng-1.2.6 JB
795 */
796#define PNG_OUT_OF_RANGE(value, ideal, delta) \
797 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
798
799/* Conversions between fixed and floating point, only defined if
800 * required (to make sure the code doesn't accidentally use float
801 * when it is supposedly disabled.)
802 */
803#ifdef PNG_FLOATING_POINT_SUPPORTED
804/* The floating point conversion can't overflow, though it can and
805 * does lose accuracy relative to the original fixed point value.
806 * In practice this doesn't matter because png_fixed_point only
807 * stores numbers with very low precision. The png_ptr and s
808 * arguments are unused by default but are there in case error
809 * checking becomes a requirement.
810 */
811#define png_float(png_ptr, fixed, s) (.00001 * (fixed))
812
813/* The fixed point conversion performs range checking and evaluates
814 * its argument multiple times, so must be used with care. The
815 * range checking uses the PNG specification values for a signed
816 * 32-bit fixed point value except that the values are deliberately
817 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
818 * (2^31-1) * 100000). 's' is a string that describes the value being
819 * converted.
820 *
821 * NOTE: this macro will raise a png_error if the range check fails,
822 * therefore it is normally only appropriate to use this on values
823 * that come from API calls or other sources where an out of range
824 * error indicates a programming error, not a data error!
825 *
826 * NOTE: by default this is off - the macro is not used - because the
827 * function call saves a lot of code.
828 */
829#ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
830#define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
831 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
832#endif
833/* else the corresponding function is defined below, inside the scope of the
834 * cplusplus test.
835 */
836#endif
837
838/* Constants for known chunk types. If you need to add a chunk, define the name
839 * here. For historical reasons these constants have the form png_<name>; i.e.
840 * the prefix is lower case. Please use decimal values as the parameters to
841 * match the ISO PNG specification and to avoid relying on the C locale
842 * interpretation of character values.
843 *
844 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
845 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
846 * to be generated if required.
847 *
848 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
849 * architectures where (int) is only 16 bits.
850 */
851#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
852#define PNG_U32(b1,b2,b3,b4) \
853 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
854
855/* Constants for known chunk types.
856 *
857 * MAINTAINERS: If you need to add a chunk, define the name here.
858 * For historical reasons these constants have the form png_<name>; i.e.
859 * the prefix is lower case. Please use decimal values as the parameters to
860 * match the ISO PNG specification and to avoid relying on the C locale
861 * interpretation of character values. Please keep the list sorted.
862 *
863 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
864 * type. In fact the specification does not express chunk types this way,
865 * however using a 32-bit value means that the chunk type can be read from the
866 * stream using exactly the same code as used for a 32-bit unsigned value and
867 * can be examined far more efficiently (using one arithmetic compare).
868 *
869 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The
870 * libpng API still uses strings for 'unknown' chunks and a macro,
871 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice
872 * that for portable code numeric values must still be used; the string "IHDR"
873 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
874 *
875 * In 1.7.0 the definitions will be made public in png.h to avoid having to
876 * duplicate the same definitions in application code.
877 */
878#define png_IDAT PNG_U32( 73, 68, 65, 84)
879#define png_IEND PNG_U32( 73, 69, 78, 68)
880#define png_IHDR PNG_U32( 73, 72, 68, 82)
881#define png_PLTE PNG_U32( 80, 76, 84, 69)
882#define png_bKGD PNG_U32( 98, 75, 71, 68)
883#define png_cHRM PNG_U32( 99, 72, 82, 77)
884#define png_eXIf PNG_U32(101, 88, 73, 102) /* registered July 2017 */
885#define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
886#define png_gAMA PNG_U32(103, 65, 77, 65)
887#define png_gIFg PNG_U32(103, 73, 70, 103)
888#define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
889#define png_gIFx PNG_U32(103, 73, 70, 120)
890#define png_hIST PNG_U32(104, 73, 83, 84)
891#define png_iCCP PNG_U32(105, 67, 67, 80)
892#define png_iTXt PNG_U32(105, 84, 88, 116)
893#define png_oFFs PNG_U32(111, 70, 70, 115)
894#define png_pCAL PNG_U32(112, 67, 65, 76)
895#define png_pHYs PNG_U32(112, 72, 89, 115)
896#define png_sBIT PNG_U32(115, 66, 73, 84)
897#define png_sCAL PNG_U32(115, 67, 65, 76)
898#define png_sPLT PNG_U32(115, 80, 76, 84)
899#define png_sRGB PNG_U32(115, 82, 71, 66)
900#define png_sTER PNG_U32(115, 84, 69, 82)
901#define png_tEXt PNG_U32(116, 69, 88, 116)
902#define png_tIME PNG_U32(116, 73, 77, 69)
903#define png_tRNS PNG_U32(116, 82, 78, 83)
904#define png_zTXt PNG_U32(122, 84, 88, 116)
905
906/* The following will work on (signed char*) strings, whereas the get_uint_32
907 * macro will fail on top-bit-set values because of the sign extension.
908 */
909#define PNG_CHUNK_FROM_STRING(s)\
910 PNG_U32(0xff & (s)[0], 0xff & (s)[1], 0xff & (s)[2], 0xff & (s)[3])
911
912/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
913 * signed and the argument is a (char[]) This macro will fail miserably on
914 * systems where (char) is more than 8 bits.
915 */
916#define PNG_STRING_FROM_CHUNK(s,c)\
917 (void)(((char*)(s))[0]=(char)(((c)>>24) & 0xff), \
918 ((char*)(s))[1]=(char)(((c)>>16) & 0xff),\
919 ((char*)(s))[2]=(char)(((c)>>8) & 0xff), \
920 ((char*)(s))[3]=(char)((c & 0xff)))
921
922/* Do the same but terminate with a null character. */
923#define PNG_CSTRING_FROM_CHUNK(s,c)\
924 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
925
926/* Test on flag values as defined in the spec (section 5.4): */
927#define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
928#define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
929#define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
930#define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
931#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
932
933/* Gamma values (new at libpng-1.5.4): */
934#define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
935#define PNG_GAMMA_MAC_INVERSE 65909
936#define PNG_GAMMA_sRGB_INVERSE 45455
937
938/* Almost everything below is C specific; the #defines above can be used in
939 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
940 */
941#ifndef PNG_VERSION_INFO_ONLY
942
943#include "pngstruct.h"
944#include "pnginfo.h"
945
946/* Validate the include paths - the include path used to generate pnglibconf.h
947 * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
948 */
949#if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
950# error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
951 "-I (include path) error: see the notes in pngpriv.h"
952 /* This means that when pnglibconf.h was built the copy of zlib.h that it
953 * used is not the same as the one being used here. Because the build of
954 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
955 * zlib version number and because this affects handling of certain broken
956 * PNG files the -I directives must match.
957 *
958 * The most likely explanation is that you passed a -I in CFLAGS. This will
959 * not work; all the preprocessor directives and in particular all the -I
960 * directives must be in CPPFLAGS.
961 */
962#endif
963
964/* This is used for 16-bit gamma tables -- only the top level pointers are
965 * const; this could be changed:
966 */
967typedef const png_uint_16p * png_const_uint_16pp;
968
969/* Added to libpng-1.5.7: sRGB conversion tables */
970#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
971 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
972#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
973PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
974 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
975 * 0..65535. This table gives the closest 16-bit answers (no errors).
976 */
977#endif
978
979PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
980PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
981
982#define PNG_sRGB_FROM_LINEAR(linear) \
983 ((png_byte)(0xff & ((png_sRGB_base[(linear)>>15] \
984 + ((((linear) & 0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8)))
985 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
986 * encoded value with maximum error 0.646365. Note that the input is not a
987 * 16-bit value; it has been multiplied by 255! */
988#endif /* SIMPLIFIED_READ/WRITE */
989
990
991/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
992#ifdef __cplusplus
993extern "C" {
994#endif /* __cplusplus */
995
996/* Internal functions; these are not exported from a DLL however because they
997 * are used within several of the C source files they have to be C extern.
998 *
999 * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
1000 */
1001
1002/* Zlib support */
1003#define PNG_UNEXPECTED_ZLIB_RETURN (-7)
1004PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
1005 PNG_EMPTY);
1006 /* Used by the zlib handling functions to ensure that z_stream::msg is always
1007 * set before they return.
1008 */
1009
1010#ifdef PNG_WRITE_SUPPORTED
1011PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
1012 png_compression_bufferp *list),PNG_EMPTY);
1013 /* Free the buffer list used by the compressed write code. */
1014#endif
1015
1016#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
1017 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
1018 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
1019 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
1020 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
1021 (defined(PNG_sCAL_SUPPORTED) && \
1022 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
1023PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
1024 double fp, png_const_charp text),PNG_EMPTY);
1025#endif
1026
1027/* Check the user version string for compatibility, returns false if the version
1028 * numbers aren't compatible.
1029 */
1030PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
1031 png_const_charp user_png_ver),PNG_EMPTY);
1032
1033/* Internal base allocator - no messages, NULL on failure to allocate. This
1034 * does, however, call the application provided allocator and that could call
1035 * png_error (although that would be a bug in the application implementation.)
1036 */
1037PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
1038 png_alloc_size_t size),PNG_ALLOCATED);
1039
1040#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
1041 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
1042/* Internal array allocator, outputs no error or warning messages on failure,
1043 * just returns NULL.
1044 */
1045PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
1046 int nelements, size_t element_size),PNG_ALLOCATED);
1047
1048/* The same but an existing array is extended by add_elements. This function
1049 * also memsets the new elements to 0 and copies the old elements. The old
1050 * array is not freed or altered.
1051 */
1052PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
1053 png_const_voidp array, int old_elements, int add_elements,
1054 size_t element_size),PNG_ALLOCATED);
1055#endif /* text, sPLT or unknown chunks */
1056
1057/* Magic to create a struct when there is no struct to call the user supplied
1058 * memory allocators. Because error handling has not been set up the memory
1059 * handlers can't safely call png_error, but this is an obscure and undocumented
1060 * restriction so libpng has to assume that the 'free' handler, at least, might
1061 * call png_error.
1062 */
1063PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
1064 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
1065 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
1066 png_free_ptr free_fn),PNG_ALLOCATED);
1067
1068/* Free memory from internal libpng struct */
1069PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
1070 PNG_EMPTY);
1071
1072/* Free an allocated jmp_buf (always succeeds) */
1073PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
1074
1075/* Function to allocate memory for zlib. PNGAPI is disallowed. */
1076PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
1077 PNG_ALLOCATED);
1078
1079/* Function to free memory for zlib. PNGAPI is disallowed. */
1080PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
1081
1082/* Next four functions are used internally as callbacks. PNGCBAPI is required
1083 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
1084 * PNGCBAPI at 1.5.0
1085 */
1086
1087PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
1088 png_bytep data, size_t length),PNG_EMPTY);
1089
1090#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1091PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
1092 png_bytep buffer, size_t length),PNG_EMPTY);
1093#endif
1094
1095PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
1096 png_bytep data, size_t length),PNG_EMPTY);
1097
1098#ifdef PNG_WRITE_FLUSH_SUPPORTED
1099# ifdef PNG_STDIO_SUPPORTED
1100PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
1101 PNG_EMPTY);
1102# endif
1103#endif
1104
1105/* Reset the CRC variable */
1106PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
1107
1108/* Write the "data" buffer to whatever output you are using */
1109PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
1110 png_const_bytep data, size_t length),PNG_EMPTY);
1111
1112/* Read and check the PNG file signature */
1113PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
1114 png_inforp info_ptr),PNG_EMPTY);
1115
1116/* Read the chunk header (length + type name) */
1117PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
1118 PNG_EMPTY);
1119
1120/* Read data from whatever input you are using into the "data" buffer */
1121PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
1122 size_t length),PNG_EMPTY);
1123
1124/* Read bytes into buf, and update png_ptr->crc */
1125PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
1126 png_uint_32 length),PNG_EMPTY);
1127
1128/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
1129PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
1130 png_uint_32 skip),PNG_EMPTY);
1131
1132/* Read the CRC from the file and compare it to the libpng calculated CRC */
1133PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
1134
1135/* Calculate the CRC over a section of data. Note that we are only
1136 * passing a maximum of 64K on systems that have this as a memory limit,
1137 * since this is the maximum buffer size we can specify.
1138 */
1139PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
1140 png_const_bytep ptr, size_t length),PNG_EMPTY);
1141
1142#ifdef PNG_WRITE_FLUSH_SUPPORTED
1143PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
1144#endif
1145
1146/* Write various chunks */
1147
1148/* Write the IHDR chunk, and update the png_struct with the necessary
1149 * information.
1150 */
1151PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
1152 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
1153 int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
1154
1155PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
1156 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
1157
1158PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
1159 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
1160 PNG_EMPTY);
1161
1162PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
1163
1164#ifdef PNG_WRITE_gAMA_SUPPORTED
1165PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
1166 png_fixed_point file_gamma),PNG_EMPTY);
1167#endif
1168
1169#ifdef PNG_WRITE_sBIT_SUPPORTED
1170PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
1171 png_const_color_8p sbit, int color_type),PNG_EMPTY);
1172#endif
1173
1174#ifdef PNG_WRITE_cHRM_SUPPORTED
1175PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
1176 const png_xy *xy), PNG_EMPTY);
1177 /* The xy value must have been previously validated */
1178#endif
1179
1180#ifdef PNG_WRITE_sRGB_SUPPORTED
1181PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
1182 int intent),PNG_EMPTY);
1183#endif
1184
1185#ifdef PNG_WRITE_eXIf_SUPPORTED
1186PNG_INTERNAL_FUNCTION(void,png_write_eXIf,(png_structrp png_ptr,
1187 png_bytep exif, int num_exif),PNG_EMPTY);
1188#endif
1189
1190#ifdef PNG_WRITE_iCCP_SUPPORTED
1191PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
1192 png_const_charp name, png_const_bytep profile), PNG_EMPTY);
1193 /* The profile must have been previously validated for correctness, the
1194 * length comes from the first four bytes. Only the base, deflate,
1195 * compression is supported.
1196 */
1197#endif
1198
1199#ifdef PNG_WRITE_sPLT_SUPPORTED
1200PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
1201 png_const_sPLT_tp palette),PNG_EMPTY);
1202#endif
1203
1204#ifdef PNG_WRITE_tRNS_SUPPORTED
1205PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
1206 png_const_bytep trans, png_const_color_16p values, int number,
1207 int color_type),PNG_EMPTY);
1208#endif
1209
1210#ifdef PNG_WRITE_bKGD_SUPPORTED
1211PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
1212 png_const_color_16p values, int color_type),PNG_EMPTY);
1213#endif
1214
1215#ifdef PNG_WRITE_hIST_SUPPORTED
1216PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
1217 png_const_uint_16p hist, int num_hist),PNG_EMPTY);
1218#endif
1219
1220/* Chunks that have keywords */
1221#ifdef PNG_WRITE_tEXt_SUPPORTED
1222PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
1223 png_const_charp key, png_const_charp text, size_t text_len),PNG_EMPTY);
1224#endif
1225
1226#ifdef PNG_WRITE_zTXt_SUPPORTED
1227PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
1228 key, png_const_charp text, int compression),PNG_EMPTY);
1229#endif
1230
1231#ifdef PNG_WRITE_iTXt_SUPPORTED
1232PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
1233 int compression, png_const_charp key, png_const_charp lang,
1234 png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
1235#endif
1236
1237#ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
1238PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
1239 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
1240#endif
1241
1242#ifdef PNG_WRITE_oFFs_SUPPORTED
1243PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
1244 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
1245#endif
1246
1247#ifdef PNG_WRITE_pCAL_SUPPORTED
1248PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
1249 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
1250 png_const_charp units, png_charpp params),PNG_EMPTY);
1251#endif
1252
1253#ifdef PNG_WRITE_pHYs_SUPPORTED
1254PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
1255 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
1256 int unit_type),PNG_EMPTY);
1257#endif
1258
1259#ifdef PNG_WRITE_tIME_SUPPORTED
1260PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
1261 png_const_timep mod_time),PNG_EMPTY);
1262#endif
1263
1264#ifdef PNG_WRITE_sCAL_SUPPORTED
1265PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
1266 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
1267#endif
1268
1269/* Called when finished processing a row of data */
1270PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
1271 PNG_EMPTY);
1272
1273/* Internal use only. Called before first row of data */
1274PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
1275 PNG_EMPTY);
1276
1277/* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
1278 * array of png_ptr->width pixels. If the image is not interlaced or this
1279 * is the final pass this just does a memcpy, otherwise the "display" flag
1280 * is used to determine whether to copy pixels that are not in the current pass.
1281 *
1282 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
1283 * function to achieve the documented 'blocky' appearance during interlaced read
1284 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
1285 * are not changed if they are not in the current pass, when display is 0.
1286 *
1287 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
1288 *
1289 * The API always reads from the png_struct row buffer and always assumes that
1290 * it is full width (png_do_read_interlace has already been called.)
1291 *
1292 * This function is only ever used to write to row buffers provided by the
1293 * caller of the relevant libpng API and the row must have already been
1294 * transformed by the read transformations.
1295 *
1296 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
1297 * bitmasks for use within the code, otherwise runtime generated masks are used.
1298 * The default is compile time masks.
1299 */
1300#ifndef PNG_USE_COMPILE_TIME_MASKS
1301# define PNG_USE_COMPILE_TIME_MASKS 1
1302#endif
1303PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
1304 png_bytep row, int display),PNG_EMPTY);
1305
1306#ifdef PNG_READ_INTERLACING_SUPPORTED
1307/* Expand an interlaced row: the 'row_info' describes the pass data that has
1308 * been read in and must correspond to the pixels in 'row', the pixels are
1309 * expanded (moved apart) in 'row' to match the final layout, when doing this
1310 * the pixels are *replicated* to the intervening space. This is essential for
1311 * the correct operation of png_combine_row, above.
1312 */
1313PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
1314 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
1315#endif
1316
1317/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
1318
1319#ifdef PNG_WRITE_INTERLACING_SUPPORTED
1320/* Grab pixels out of a row for an interlaced pass */
1321PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
1322 png_bytep row, int pass),PNG_EMPTY);
1323#endif
1324
1325/* Unfilter a row: check the filter value before calling this, there is no point
1326 * calling it for PNG_FILTER_VALUE_NONE.
1327 */
1328PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
1329 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
1330
1331#if PNG_ARM_NEON_OPT > 0
1332PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
1333 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1334PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
1335 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1336PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
1337 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1338PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
1339 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1340PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
1341 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1342PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
1343 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1344PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
1345 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1346#endif
1347
1348#if PNG_MIPS_MSA_IMPLEMENTATION == 1
1349PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_msa,(png_row_infop row_info,
1350 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1351PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_msa,(png_row_infop
1352 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1353PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_msa,(png_row_infop
1354 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1355PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_msa,(png_row_infop
1356 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1357PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_msa,(png_row_infop
1358 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1359PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_msa,(png_row_infop
1360 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1361PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_msa,(png_row_infop
1362 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1363#endif
1364
1365#if PNG_MIPS_MMI_IMPLEMENTATION > 0
1366PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_mmi,(png_row_infop row_info,
1367 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1368PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_mmi,(png_row_infop
1369 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1370PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_mmi,(png_row_infop
1371 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1372PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_mmi,(png_row_infop
1373 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1374PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_mmi,(png_row_infop
1375 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1376PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_mmi,(png_row_infop
1377 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1378PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_mmi,(png_row_infop
1379 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1380#endif
1381
1382#if PNG_POWERPC_VSX_OPT > 0
1383PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_vsx,(png_row_infop row_info,
1384 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1385PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_vsx,(png_row_infop
1386 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1387PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_vsx,(png_row_infop
1388 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1389PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_vsx,(png_row_infop
1390 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1391PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_vsx,(png_row_infop
1392 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1393PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_vsx,(png_row_infop
1394 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1395PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_vsx,(png_row_infop
1396 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1397#endif
1398
1399#if PNG_INTEL_SSE_IMPLEMENTATION > 0
1400PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
1401 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1402PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
1403 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1404PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
1405 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1406PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
1407 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1408PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
1409 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1410PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
1411 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1412#endif
1413
1414#if PNG_LOONGARCH_LSX_IMPLEMENTATION == 1
1415PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_lsx,(png_row_infop
1416 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1417PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_lsx,(png_row_infop
1418 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1419PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_lsx,(png_row_infop
1420 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1421PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_lsx,(png_row_infop
1422 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1423PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_lsx,(png_row_infop
1424 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1425PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_lsx,(png_row_infop
1426 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1427PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_lsx,(png_row_infop
1428 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1429#endif
1430
1431/* Choose the best filter to use and filter the row data */
1432PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
1433 png_row_infop row_info),PNG_EMPTY);
1434
1435#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1436PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
1437 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
1438 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer
1439 * is NULL the function checks, instead, for the end of the stream. In this
1440 * case a benign error will be issued if the stream end is not found or if
1441 * extra data has to be consumed.
1442 */
1443PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
1444 PNG_EMPTY);
1445 /* This cleans up when the IDAT LZ stream does not end when the last image
1446 * byte is read; there is still some pending input.
1447 */
1448
1449PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
1450 PNG_EMPTY);
1451 /* Finish a row while reading, dealing with interlacing passes, etc. */
1452#endif /* SEQUENTIAL_READ */
1453
1454/* Initialize the row buffers, etc. */
1455PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
1456
1457#if ZLIB_VERNUM >= 0x1240
1458PNG_INTERNAL_FUNCTION(int,png_zlib_inflate,(png_structrp png_ptr, int flush),
1459 PNG_EMPTY);
1460# define PNG_INFLATE(pp, flush) png_zlib_inflate(pp, flush)
1461#else /* Zlib < 1.2.4 */
1462# define PNG_INFLATE(pp, flush) inflate(&(pp)->zstream, flush)
1463#endif /* Zlib < 1.2.4 */
1464
1465#ifdef PNG_READ_TRANSFORMS_SUPPORTED
1466/* Optional call to update the users info structure */
1467PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
1468 png_inforp info_ptr),PNG_EMPTY);
1469#endif
1470
1471/* Shared transform functions, defined in pngtran.c */
1472#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1473 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1474PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
1475 png_bytep row, int at_start),PNG_EMPTY);
1476#endif
1477
1478#ifdef PNG_16BIT_SUPPORTED
1479#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1480PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
1481 png_bytep row),PNG_EMPTY);
1482#endif
1483#endif
1484
1485#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1486 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1487PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
1488 png_bytep row),PNG_EMPTY);
1489#endif
1490
1491#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1492PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
1493 png_bytep row),PNG_EMPTY);
1494#endif
1495
1496#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1497PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
1498 png_bytep row),PNG_EMPTY);
1499#endif
1500
1501/* The following decodes the appropriate chunks, and does error correction,
1502 * then calls the appropriate callback for the chunk if it is valid.
1503 */
1504
1505/* Decode the IHDR chunk */
1506PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
1507 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1508PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
1509 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1510PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
1511 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1512
1513#ifdef PNG_READ_bKGD_SUPPORTED
1514PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
1515 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1516#endif
1517
1518#ifdef PNG_READ_cHRM_SUPPORTED
1519PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
1520 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1521#endif
1522
1523#ifdef PNG_READ_eXIf_SUPPORTED
1524PNG_INTERNAL_FUNCTION(void,png_handle_eXIf,(png_structrp png_ptr,
1525 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1526#endif
1527
1528#ifdef PNG_READ_gAMA_SUPPORTED
1529PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
1530 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1531#endif
1532
1533#ifdef PNG_READ_hIST_SUPPORTED
1534PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
1535 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1536#endif
1537
1538#ifdef PNG_READ_iCCP_SUPPORTED
1539PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
1540 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1541#endif /* READ_iCCP */
1542
1543#ifdef PNG_READ_iTXt_SUPPORTED
1544PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
1545 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1546#endif
1547
1548#ifdef PNG_READ_oFFs_SUPPORTED
1549PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
1550 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1551#endif
1552
1553#ifdef PNG_READ_pCAL_SUPPORTED
1554PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
1555 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1556#endif
1557
1558#ifdef PNG_READ_pHYs_SUPPORTED
1559PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
1560 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1561#endif
1562
1563#ifdef PNG_READ_sBIT_SUPPORTED
1564PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
1565 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1566#endif
1567
1568#ifdef PNG_READ_sCAL_SUPPORTED
1569PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
1570 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1571#endif
1572
1573#ifdef PNG_READ_sPLT_SUPPORTED
1574PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
1575 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1576#endif /* READ_sPLT */
1577
1578#ifdef PNG_READ_sRGB_SUPPORTED
1579PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
1580 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1581#endif
1582
1583#ifdef PNG_READ_tEXt_SUPPORTED
1584PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
1585 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1586#endif
1587
1588#ifdef PNG_READ_tIME_SUPPORTED
1589PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
1590 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1591#endif
1592
1593#ifdef PNG_READ_tRNS_SUPPORTED
1594PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
1595 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1596#endif
1597
1598#ifdef PNG_READ_zTXt_SUPPORTED
1599PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
1600 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1601#endif
1602
1603PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_const_structrp png_ptr,
1604 png_uint_32 chunk_name),PNG_EMPTY);
1605
1606PNG_INTERNAL_FUNCTION(void,png_check_chunk_length,(png_const_structrp png_ptr,
1607 png_uint_32 chunk_length),PNG_EMPTY);
1608
1609PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
1610 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
1611 /* This is the function that gets called for unknown chunks. The 'keep'
1612 * argument is either non-zero for a known chunk that has been set to be
1613 * handled as unknown or zero for an unknown chunk. By default the function
1614 * just skips the chunk or errors out if it is critical.
1615 */
1616
1617#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
1618 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
1619PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
1620 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
1621 /* Exactly as the API png_handle_as_unknown() except that the argument is a
1622 * 32-bit chunk name, not a string.
1623 */
1624#endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
1625
1626/* Handle the transformations for reading and writing */
1627#ifdef PNG_READ_TRANSFORMS_SUPPORTED
1628PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
1629 png_row_infop row_info),PNG_EMPTY);
1630#endif
1631#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1632PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
1633 png_row_infop row_info),PNG_EMPTY);
1634#endif
1635
1636#ifdef PNG_READ_TRANSFORMS_SUPPORTED
1637PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
1638 PNG_EMPTY);
1639#endif
1640
1641#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1642PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
1643 png_inforp info_ptr),PNG_EMPTY);
1644PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
1645 png_inforp info_ptr),PNG_EMPTY);
1646PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
1647PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
1648 PNG_EMPTY);
1649PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
1650 png_bytep buffer, size_t buffer_length),PNG_EMPTY);
1651PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
1652PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
1653 png_bytep buffer, size_t buffer_length),PNG_EMPTY);
1654PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
1655 PNG_EMPTY);
1656PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
1657 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1658PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
1659 png_inforp info_ptr),PNG_EMPTY);
1660PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
1661 png_inforp info_ptr),PNG_EMPTY);
1662PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
1663 png_bytep row),PNG_EMPTY);
1664PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
1665 png_inforp info_ptr),PNG_EMPTY);
1666PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
1667 png_inforp info_ptr),PNG_EMPTY);
1668PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
1669 PNG_EMPTY);
1670# ifdef PNG_READ_tEXt_SUPPORTED
1671PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
1672 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1673PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
1674 png_inforp info_ptr),PNG_EMPTY);
1675# endif
1676# ifdef PNG_READ_zTXt_SUPPORTED
1677PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
1678 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1679PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
1680 png_inforp info_ptr),PNG_EMPTY);
1681# endif
1682# ifdef PNG_READ_iTXt_SUPPORTED
1683PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
1684 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1685PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
1686 png_inforp info_ptr),PNG_EMPTY);
1687# endif
1688
1689#endif /* PROGRESSIVE_READ */
1690
1691/* Added at libpng version 1.6.0 */
1692#ifdef PNG_GAMMA_SUPPORTED
1693PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
1694 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
1695 /* Set the colorspace gamma with a value provided by the application or by
1696 * the gAMA chunk on read. The value will override anything set by an ICC
1697 * profile.
1698 */
1699
1700PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
1701 png_inforp info_ptr), PNG_EMPTY);
1702 /* Synchronize the info 'valid' flags with the colorspace */
1703
1704PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
1705 png_inforp info_ptr), PNG_EMPTY);
1706 /* Copy the png_struct colorspace to the info_struct and call the above to
1707 * synchronize the flags. Checks for NULL info_ptr and does nothing.
1708 */
1709#endif
1710
1711/* Added at libpng version 1.4.0 */
1712#ifdef PNG_COLORSPACE_SUPPORTED
1713/* These internal functions are for maintaining the colorspace structure within
1714 * a png_info or png_struct (or, indeed, both).
1715 */
1716PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
1717 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
1718 int preferred), PNG_EMPTY);
1719
1720PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
1721 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
1722 int preferred), PNG_EMPTY);
1723
1724#ifdef PNG_sRGB_SUPPORTED
1725PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
1726 png_colorspacerp colorspace, int intent), PNG_EMPTY);
1727 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
1728 * flags to write them, if it returns false there was a problem and an error
1729 * message has already been output (but the colorspace may still need to be
1730 * synced to record the invalid flag).
1731 */
1732#endif /* sRGB */
1733
1734#ifdef PNG_iCCP_SUPPORTED
1735PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
1736 png_colorspacerp colorspace, png_const_charp name,
1737 png_uint_32 profile_length, png_const_bytep profile, int color_type),
1738 PNG_EMPTY);
1739 /* The 'name' is used for information only */
1740
1741/* Routines for checking parts of an ICC profile. */
1742#ifdef PNG_READ_iCCP_SUPPORTED
1743PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
1744 png_colorspacerp colorspace, png_const_charp name,
1745 png_uint_32 profile_length), PNG_EMPTY);
1746#endif /* READ_iCCP */
1747PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
1748 png_colorspacerp colorspace, png_const_charp name,
1749 png_uint_32 profile_length,
1750 png_const_bytep profile /* first 132 bytes only */, int color_type),
1751 PNG_EMPTY);
1752PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
1753 png_colorspacerp colorspace, png_const_charp name,
1754 png_uint_32 profile_length,
1755 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
1756#ifdef PNG_sRGB_SUPPORTED
1757PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
1758 png_const_structrp png_ptr, png_colorspacerp colorspace,
1759 png_const_bytep profile, uLong adler), PNG_EMPTY);
1760 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
1761 * be zero to indicate that it is not available. It is used, if provided,
1762 * as a fast check on the profile when checking to see if it is sRGB.
1763 */
1764#endif
1765#endif /* iCCP */
1766
1767#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1768PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
1769 (png_structrp png_ptr), PNG_EMPTY);
1770 /* Set the rgb_to_gray coefficients from the colorspace Y values */
1771#endif /* READ_RGB_TO_GRAY */
1772#endif /* COLORSPACE */
1773
1774/* Added at libpng version 1.4.0 */
1775PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
1776 png_uint_32 width, png_uint_32 height, int bit_depth,
1777 int color_type, int interlace_type, int compression_type,
1778 int filter_type),PNG_EMPTY);
1779
1780/* Added at libpng version 1.5.10 */
1781#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
1782 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
1783PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
1784 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
1785#endif
1786
1787#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1788PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
1789 png_const_charp name),PNG_NORETURN);
1790#endif
1791
1792/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1793 * the end. Always leaves the buffer nul terminated. Never errors out (and
1794 * there is no error code.)
1795 */
1796PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
1797 size_t pos, png_const_charp string),PNG_EMPTY);
1798
1799/* Various internal functions to handle formatted warning messages, currently
1800 * only implemented for warnings.
1801 */
1802#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1803/* Utility to dump an unsigned value into a buffer, given a start pointer and
1804 * and end pointer (which should point just *beyond* the end of the buffer!)
1805 * Returns the pointer to the start of the formatted string. This utility only
1806 * does unsigned values.
1807 */
1808PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
1809 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
1810
1811/* Convenience macro that takes an array: */
1812#define PNG_FORMAT_NUMBER(buffer,format,number) \
1813 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1814
1815/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1816#define PNG_NUMBER_BUFFER_SIZE 24
1817
1818/* These are the integer formats currently supported, the name is formed from
1819 * the standard printf(3) format string.
1820 */
1821#define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1822#define PNG_NUMBER_FORMAT_02u 2
1823#define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1824#define PNG_NUMBER_FORMAT_02d 2
1825#define PNG_NUMBER_FORMAT_x 3
1826#define PNG_NUMBER_FORMAT_02x 4
1827#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1828#endif
1829
1830#ifdef PNG_WARNINGS_SUPPORTED
1831/* New defines and members adding in libpng-1.5.4 */
1832# define PNG_WARNING_PARAMETER_SIZE 32
1833# define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
1834
1835/* An l-value of this type has to be passed to the APIs below to cache the
1836 * values of the parameters to a formatted warning message.
1837 */
1838typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1839 PNG_WARNING_PARAMETER_SIZE];
1840
1841PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
1842 int number, png_const_charp string),PNG_EMPTY);
1843 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1844 * including the trailing '\0'.
1845 */
1846PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
1847 (png_warning_parameters p, int number, int format, png_alloc_size_t value),
1848 PNG_EMPTY);
1849 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1850 * need to output. Use the following for a signed value.
1851 */
1852PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
1853 (png_warning_parameters p, int number, int format, png_int_32 value),
1854 PNG_EMPTY);
1855
1856PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
1857 png_warning_parameters p, png_const_charp message),PNG_EMPTY);
1858 /* 'message' follows the X/Open approach of using @1, @2 to insert
1859 * parameters previously supplied using the above functions. Errors in
1860 * specifying the parameters will simply result in garbage substitutions.
1861 */
1862#endif
1863
1864#ifdef PNG_BENIGN_ERRORS_SUPPORTED
1865/* Application errors (new in 1.6); use these functions (declared below) for
1866 * errors in the parameters or order of API function calls on read. The
1867 * 'warning' should be used for an error that can be handled completely; the
1868 * 'error' for one which can be handled safely but which may lose application
1869 * information or settings.
1870 *
1871 * By default these both result in a png_error call prior to release, while in a
1872 * released version the 'warning' is just a warning. However if the application
1873 * explicitly disables benign errors (explicitly permitting the code to lose
1874 * information) they both turn into warnings.
1875 *
1876 * If benign errors aren't supported they end up as the corresponding base call
1877 * (png_warning or png_error.)
1878 */
1879PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
1880 png_const_charp message),PNG_EMPTY);
1881 /* The application provided invalid parameters to an API function or called
1882 * an API function at the wrong time, libpng can completely recover.
1883 */
1884
1885PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
1886 png_const_charp message),PNG_EMPTY);
1887 /* As above but libpng will ignore the call, or attempt some other partial
1888 * recovery from the error.
1889 */
1890#else
1891# define png_app_warning(pp,s) png_warning(pp,s)
1892# define png_app_error(pp,s) png_error(pp,s)
1893#endif
1894
1895PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
1896 png_const_charp message, int error),PNG_EMPTY);
1897 /* Report a recoverable issue in chunk data. On read this is used to report
1898 * a problem found while reading a particular chunk and the
1899 * png_chunk_benign_error or png_chunk_warning function is used as
1900 * appropriate. On write this is used to report an error that comes from
1901 * data set via an application call to a png_set_ API and png_app_error or
1902 * png_app_warning is used as appropriate.
1903 *
1904 * The 'error' parameter must have one of the following values:
1905 */
1906#define PNG_CHUNK_WARNING 0 /* never an error */
1907#define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
1908#define PNG_CHUNK_ERROR 2 /* always an error */
1909
1910/* ASCII to FP interfaces, currently only implemented if sCAL
1911 * support is required.
1912 */
1913#if defined(PNG_sCAL_SUPPORTED)
1914/* MAX_DIGITS is actually the maximum number of characters in an sCAL
1915 * width or height, derived from the precision (number of significant
1916 * digits - a build time settable option) and assumptions about the
1917 * maximum ridiculous exponent.
1918 */
1919#define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1920
1921#ifdef PNG_FLOATING_POINT_SUPPORTED
1922PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
1923 png_charp ascii, size_t size, double fp, unsigned int precision),
1924 PNG_EMPTY);
1925#endif /* FLOATING_POINT */
1926
1927#ifdef PNG_FIXED_POINT_SUPPORTED
1928PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
1929 png_charp ascii, size_t size, png_fixed_point fp),PNG_EMPTY);
1930#endif /* FIXED_POINT */
1931#endif /* sCAL */
1932
1933#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1934/* An internal API to validate the format of a floating point number.
1935 * The result is the index of the next character. If the number is
1936 * not valid it will be the index of a character in the supposed number.
1937 *
1938 * The format of a number is defined in the PNG extensions specification
1939 * and this API is strictly conformant to that spec, not anyone elses!
1940 *
1941 * The format as a regular expression is:
1942 *
1943 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1944 *
1945 * or:
1946 *
1947 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1948 *
1949 * The complexity is that either integer or fraction must be present and the
1950 * fraction is permitted to have no digits only if the integer is present.
1951 *
1952 * NOTE: The dangling E problem.
1953 * There is a PNG valid floating point number in the following:
1954 *
1955 * PNG floating point numbers are not greedy.
1956 *
1957 * Working this out requires *TWO* character lookahead (because of the
1958 * sign), the parser does not do this - it will fail at the 'r' - this
1959 * doesn't matter for PNG sCAL chunk values, but it requires more care
1960 * if the value were ever to be embedded in something more complex. Use
1961 * ANSI-C strtod if you need the lookahead.
1962 */
1963/* State table for the parser. */
1964#define PNG_FP_INTEGER 0 /* before or in integer */
1965#define PNG_FP_FRACTION 1 /* before or in fraction */
1966#define PNG_FP_EXPONENT 2 /* before or in exponent */
1967#define PNG_FP_STATE 3 /* mask for the above */
1968#define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1969#define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1970#define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1971#define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1972#define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1973
1974/* These three values don't affect the parser. They are set but not used.
1975 */
1976#define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1977#define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1978#define PNG_FP_NONZERO 256 /* A non-zero value */
1979#define PNG_FP_STICKY 448 /* The above three flags */
1980
1981/* This is available for the caller to store in 'state' if required. Do not
1982 * call the parser after setting it (the parser sometimes clears it.)
1983 */
1984#define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1985
1986/* Result codes for the parser (boolean - true means ok, false means
1987 * not ok yet.)
1988 */
1989#define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1990#define PNG_FP_OK 1 /* The number is valid */
1991
1992/* Tests on the sticky non-zero and negative flags. To pass these checks
1993 * the state must also indicate that the whole number is valid - this is
1994 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1995 * is equivalent to PNG_FP_OK above.)
1996 */
1997#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1998 /* NZ_MASK: the string is valid and a non-zero negative value */
1999#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
2000 /* Z MASK: the string is valid and a non-zero value. */
2001 /* PNG_FP_SAW_DIGIT: the string is valid. */
2002#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
2003#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
2004#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
2005
2006/* The actual parser. This can be called repeatedly. It updates
2007 * the index into the string and the state variable (which must
2008 * be initialized to 0). It returns a result code, as above. There
2009 * is no point calling the parser any more if it fails to advance to
2010 * the end of the string - it is stuck on an invalid character (or
2011 * terminated by '\0').
2012 *
2013 * Note that the pointer will consume an E or even an E+ and then leave
2014 * a 'maybe' state even though a preceding integer.fraction is valid.
2015 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
2016 * a valid number. It's possible to recover from this by calling
2017 * the parser again (from the start, with state 0) but with a string
2018 * that omits the last character (i.e. set the size to the index of
2019 * the problem character.) This has not been tested within libpng.
2020 */
2021PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
2022 size_t size, int *statep, size_t *whereami),PNG_EMPTY);
2023
2024/* This is the same but it checks a complete string and returns true
2025 * only if it just contains a floating point number. As of 1.5.4 this
2026 * function also returns the state at the end of parsing the number if
2027 * it was valid (otherwise it returns 0.) This can be used for testing
2028 * for negative or zero values using the sticky flag.
2029 */
2030PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
2031 size_t size),PNG_EMPTY);
2032#endif /* pCAL || sCAL */
2033
2034#if defined(PNG_GAMMA_SUPPORTED) ||\
2035 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
2036/* Added at libpng version 1.5.0 */
2037/* This is a utility to provide a*times/div (rounded) and indicate
2038 * if there is an overflow. The result is a boolean - false (0)
2039 * for overflow, true (1) if no overflow, in which case *res
2040 * holds the result.
2041 */
2042PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
2043 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
2044#endif
2045
2046#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
2047/* Same deal, but issue a warning on overflow and return 0. */
2048PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
2049 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
2050 png_int_32 divided_by),PNG_EMPTY);
2051#endif
2052
2053#ifdef PNG_GAMMA_SUPPORTED
2054/* Calculate a reciprocal - used for gamma values. This returns
2055 * 0 if the argument is 0 in order to maintain an undefined value;
2056 * there are no warnings.
2057 */
2058PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
2059 PNG_EMPTY);
2060
2061#ifdef PNG_READ_GAMMA_SUPPORTED
2062/* The same but gives a reciprocal of the product of two fixed point
2063 * values. Accuracy is suitable for gamma calculations but this is
2064 * not exact - use png_muldiv for that. Only required at present on read.
2065 */
2066PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
2067 png_fixed_point b),PNG_EMPTY);
2068#endif
2069
2070/* Return true if the gamma value is significantly different from 1.0 */
2071PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
2072 PNG_EMPTY);
2073#endif
2074
2075#ifdef PNG_READ_GAMMA_SUPPORTED
2076/* Internal fixed point gamma correction. These APIs are called as
2077 * required to convert single values - they don't need to be fast,
2078 * they are not used when processing image pixel values.
2079 *
2080 * While the input is an 'unsigned' value it must actually be the
2081 * correct bit value - 0..255 or 0..65535 as required.
2082 */
2083PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
2084 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
2085PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
2086 png_fixed_point gamma_value),PNG_EMPTY);
2087PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
2088 png_fixed_point gamma_value),PNG_EMPTY);
2089PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
2090 PNG_EMPTY);
2091PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
2092 int bit_depth),PNG_EMPTY);
2093#endif
2094
2095/* SIMPLIFIED READ/WRITE SUPPORT */
2096#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
2097 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
2098/* The internal structure that png_image::opaque points to. */
2099typedef struct png_control
2100{
2101 png_structp png_ptr;
2102 png_infop info_ptr;
2103 png_voidp error_buf; /* Always a jmp_buf at present. */
2104
2105 png_const_bytep memory; /* Memory buffer. */
2106 size_t size; /* Size of the memory buffer. */
2107
2108 unsigned int for_write :1; /* Otherwise it is a read structure */
2109 unsigned int owned_file :1; /* We own the file in io_ptr */
2110} png_control;
2111
2112/* Return the pointer to the jmp_buf from a png_control: necessary because C
2113 * does not reveal the type of the elements of jmp_buf.
2114 */
2115#ifdef __cplusplus
2116# define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
2117#else
2118# define png_control_jmp_buf(pc) ((pc)->error_buf)
2119#endif
2120
2121/* Utility to safely execute a piece of libpng code catching and logging any
2122 * errors that might occur. Returns true on success, false on failure (either
2123 * of the function or as a result of a png_error.)
2124 */
2125PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr,
2126 png_const_charp error_message),PNG_NORETURN);
2127
2128#ifdef PNG_WARNINGS_SUPPORTED
2129PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr,
2130 png_const_charp warning_message),PNG_EMPTY);
2131#else
2132# define png_safe_warning 0/*dummy argument*/
2133#endif
2134
2135PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
2136 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
2137
2138/* Utility to log an error; this also cleans up the png_image; the function
2139 * always returns 0 (false).
2140 */
2141PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
2142 png_const_charp error_message),PNG_EMPTY);
2143
2144#ifndef PNG_SIMPLIFIED_READ_SUPPORTED
2145/* png_image_free is used by the write code but not exported */
2146PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
2147#endif /* !SIMPLIFIED_READ */
2148
2149#endif /* SIMPLIFIED READ/WRITE */
2150
2151/* These are initialization functions for hardware specific PNG filter
2152 * optimizations; list these here then select the appropriate one at compile
2153 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
2154 * the generic code is used.
2155 */
2156#ifdef PNG_FILTER_OPTIMIZATIONS
2157PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
2158 unsigned int bpp), PNG_EMPTY);
2159 /* Just declare the optimization that will be used */
2160#else
2161 /* List *all* the possible optimizations here - this branch is required if
2162 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
2163 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
2164 */
2165# if PNG_ARM_NEON_OPT > 0
2166PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
2167 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2168#endif
2169
2170#if PNG_MIPS_MSA_IMPLEMENTATION == 1
2171PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_mips,
2172 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2173#endif
2174
2175# if PNG_MIPS_MMI_IMPLEMENTATION > 0
2176PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_mips,
2177 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2178# endif
2179
2180# if PNG_INTEL_SSE_IMPLEMENTATION > 0
2181PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
2182 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2183# endif
2184#endif
2185
2186#if PNG_LOONGARCH_LSX_OPT > 0
2187PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_lsx,
2188 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2189#endif
2190
2191PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
2192 png_const_charp key, png_bytep new_key), PNG_EMPTY);
2193
2194#if PNG_ARM_NEON_IMPLEMENTATION == 1
2195PNG_INTERNAL_FUNCTION(void,
2196 png_riffle_palette_neon,
2197 (png_structrp),
2198 PNG_EMPTY);
2199PNG_INTERNAL_FUNCTION(int,
2200 png_do_expand_palette_rgba8_neon,
2201 (png_structrp,
2202 png_row_infop,
2203 png_const_bytep,
2204 const png_bytepp,
2205 const png_bytepp),
2206 PNG_EMPTY);
2207PNG_INTERNAL_FUNCTION(int,
2208 png_do_expand_palette_rgb8_neon,
2209 (png_structrp,
2210 png_row_infop,
2211 png_const_bytep,
2212 const png_bytepp,
2213 const png_bytepp),
2214 PNG_EMPTY);
2215#endif
2216
2217/* Maintainer: Put new private prototypes here ^ */
2218
2219#include "pngdebug.h"
2220
2221#ifdef __cplusplus
2222}
2223#endif
2224
2225#endif /* PNG_VERSION_INFO_ONLY */
2226#endif /* PNGPRIV_H */
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