1/*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 */
24
25/* pngpriv.h - private declarations for use inside libpng
26 *
27 * This file is available under and governed by the GNU General Public
28 * License version 2 only, as published by the Free Software Foundation.
29 * However, the following notice accompanied the original version of this
30 * file and, per its terms, should not be removed:
31 *
32 * Last changed in libpng 1.6.35 [July 15, 2018]
33 * Copyright (c) 1998-2002,2004,2006-2018 Glenn Randers-Pehrson
34 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
35 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
36 *
37 * This code is released under the libpng license.
38 * For conditions of distribution and use, see the disclaimer
39 * and license in png.h
40 */
41
42/* The symbols declared in this file (including the functions declared
43 * as extern) are PRIVATE. They are not part of the libpng public
44 * interface, and are not recommended for use by regular applications.
45 * Some of them may become public in the future; others may stay private,
46 * change in an incompatible way, or even disappear.
47 * Although the libpng users are not forbidden to include this header,
48 * they should be well aware of the issues that may arise from doing so.
49 */
50
51#ifndef PNGPRIV_H
52#define PNGPRIV_H
53
54/* Feature Test Macros. The following are defined here to ensure that correctly
55 * implemented libraries reveal the APIs libpng needs to build and hide those
56 * that are not needed and potentially damaging to the compilation.
57 *
58 * Feature Test Macros must be defined before any system header is included (see
59 * POSIX 1003.1 2.8.2 "POSIX Symbols."
60 *
61 * These macros only have an effect if the operating system supports either
62 * POSIX 1003.1 or C99, or both. On other operating systems (particularly
63 * Windows/Visual Studio) there is no effect; the OS specific tests below are
64 * still required (as of 2011-05-02.)
65 */
66#ifndef _POSIX_SOURCE
67# define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
68#endif
69
70#ifndef PNG_VERSION_INFO_ONLY
71/* Standard library headers not required by png.h: */
72# include <stdlib.h>
73# include <string.h>
74#endif
75
76#define PNGLIB_BUILD /*libpng is being built, not used*/
77
78/* If HAVE_CONFIG_H is defined during the build then the build system must
79 * provide an appropriate "config.h" file on the include path. The header file
80 * must provide definitions as required below (search for "HAVE_CONFIG_H");
81 * see configure.ac for more details of the requirements. The macro
82 * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on
83 * 'configure'; define this macro to prevent the configure build including the
84 * configure generated config.h. Libpng is expected to compile without *any*
85 * special build system support on a reasonably ANSI-C compliant system.
86 */
87#if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
88# include <config.h>
89
90 /* Pick up the definition of 'restrict' from config.h if it was read: */
91# define PNG_RESTRICT restrict
92#endif
93
94/* To support symbol prefixing it is necessary to know *before* including png.h
95 * whether the fixed point (and maybe other) APIs are exported, because if they
96 * are not internal definitions may be required. This is handled below just
97 * before png.h is included, but load the configuration now if it is available.
98 */
99#ifndef PNGLCONF_H
100# include "pnglibconf.h"
101#endif
102
103/* Local renames may change non-exported API functions from png.h */
104#if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
105# include "pngprefix.h"
106#endif
107
108#ifdef PNG_USER_CONFIG
109# include "pngusr.h"
110 /* These should have been defined in pngusr.h */
111# ifndef PNG_USER_PRIVATEBUILD
112# define PNG_USER_PRIVATEBUILD "Custom libpng build"
113# endif
114# ifndef PNG_USER_DLLFNAME_POSTFIX
115# define PNG_USER_DLLFNAME_POSTFIX "Cb"
116# endif
117#endif
118
119/* Compile time options.
120 * =====================
121 * In a multi-arch build the compiler may compile the code several times for the
122 * same object module, producing different binaries for different architectures.
123 * When this happens configure-time setting of the target host options cannot be
124 * done and this interferes with the handling of the ARM NEON optimizations, and
125 * possibly other similar optimizations. Put additional tests here; in general
126 * this is needed when the same option can be changed at both compile time and
127 * run time depending on the target OS (i.e. iOS vs Android.)
128 *
129 * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
130 * this is not possible with certain compilers (Oracle SUN OS CC), as a result
131 * it is necessary to ensure that all extern functions that *might* be used
132 * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__
133 * below is one example of this behavior because it is controlled by the
134 * presence or not of -mfpu=neon on the GCC command line, it is possible to do
135 * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
136 * do this.
137 */
138#ifndef PNG_ARM_NEON_OPT
139 /* ARM NEON optimizations are being controlled by the compiler settings,
140 * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon
141 * with GCC) then the compiler will define __ARM_NEON__ and we can rely
142 * unconditionally on NEON instructions not crashing, otherwise we must
143 * disable use of NEON instructions.
144 *
145 * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
146 * can only be turned on automatically if that is supported too. If
147 * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
148 * to compile with an appropriate #error if ALIGNED_MEMORY has been turned
149 * off.
150 *
151 * Note that gcc-4.9 defines __ARM_NEON instead of the deprecated
152 * __ARM_NEON__, so we check both variants.
153 *
154 * To disable ARM_NEON optimizations entirely, and skip compiling the
155 * associated assembler code, pass --enable-arm-neon=no to configure
156 * or put -DPNG_ARM_NEON_OPT=0 in CPPFLAGS.
157 */
158# if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \
159 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
160# define PNG_ARM_NEON_OPT 2
161# else
162# define PNG_ARM_NEON_OPT 0
163# endif
164#endif
165
166#if PNG_ARM_NEON_OPT > 0
167 /* NEON optimizations are to be at least considered by libpng, so enable the
168 * callbacks to do this.
169 */
170# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
171
172 /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used
173 * if possible - if __ARM_NEON__ is set and the compiler version is not known
174 * to be broken. This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can
175 * be:
176 *
177 * 1 The intrinsics code (the default with __ARM_NEON__)
178 * 2 The hand coded assembler (the default without __ARM_NEON__)
179 *
180 * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however
181 * this is *NOT* supported and may cease to work even after a minor revision
182 * to libpng. It *is* valid to do this for testing purposes, e.g. speed
183 * testing or a new compiler, but the results should be communicated to the
184 * libpng implementation list for incorporation in the next minor release.
185 */
186# ifndef PNG_ARM_NEON_IMPLEMENTATION
187# if defined(__ARM_NEON__) || defined(__ARM_NEON)
188# if defined(__clang__)
189 /* At present it is unknown by the libpng developers which versions
190 * of clang support the intrinsics, however some or perhaps all
191 * versions do not work with the assembler so this may be
192 * irrelevant, so just use the default (do nothing here.)
193 */
194# elif defined(__GNUC__)
195 /* GCC 4.5.4 NEON support is known to be broken. 4.6.3 is known to
196 * work, so if this *is* GCC, or G++, look for a version >4.5
197 */
198# if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)
199# define PNG_ARM_NEON_IMPLEMENTATION 2
200# endif /* no GNUC support */
201# endif /* __GNUC__ */
202# else /* !defined __ARM_NEON__ */
203 /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
204 */
205# define PNG_ARM_NEON_IMPLEMENTATION 2
206# endif /* __ARM_NEON__ */
207# endif /* !PNG_ARM_NEON_IMPLEMENTATION */
208
209# ifndef PNG_ARM_NEON_IMPLEMENTATION
210 /* Use the intrinsics code by default. */
211# define PNG_ARM_NEON_IMPLEMENTATION 1
212# endif
213#endif /* PNG_ARM_NEON_OPT > 0 */
214
215#ifndef PNG_MIPS_MSA_OPT
216# if defined(__mips_msa) && (__mips_isa_rev >= 5) && defined(PNG_ALIGNED_MEMORY_SUPPORTED)
217# define PNG_MIPS_MSA_OPT 2
218# else
219# define PNG_MIPS_MSA_OPT 0
220# endif
221#endif
222
223#ifndef PNG_POWERPC_VSX_OPT
224# if defined(__PPC64__) && defined(__ALTIVEC__) && defined(__VSX__)
225# define PNG_POWERPC_VSX_OPT 2
226# else
227# define PNG_POWERPC_VSX_OPT 0
228# endif
229#endif
230
231#ifndef PNG_INTEL_SSE_OPT
232# ifdef PNG_INTEL_SSE
233 /* Only check for SSE if the build configuration has been modified to
234 * enable SSE optimizations. This means that these optimizations will
235 * be off by default. See contrib/intel for more details.
236 */
237# if defined(__SSE4_1__) || defined(__AVX__) || defined(__SSSE3__) || \
238 defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
239 (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
240# define PNG_INTEL_SSE_OPT 1
241# else
242# define PNG_INTEL_SSE_OPT 0
243# endif
244# else
245# define PNG_INTEL_SSE_OPT 0
246# endif
247#endif
248
249#if PNG_INTEL_SSE_OPT > 0
250# ifndef PNG_INTEL_SSE_IMPLEMENTATION
251# if defined(__SSE4_1__) || defined(__AVX__)
252 /* We are not actually using AVX, but checking for AVX is the best
253 way we can detect SSE4.1 and SSSE3 on MSVC.
254 */
255# define PNG_INTEL_SSE_IMPLEMENTATION 3
256# elif defined(__SSSE3__)
257# define PNG_INTEL_SSE_IMPLEMENTATION 2
258# elif defined(__SSE2__) || defined(_M_X64) || defined(_M_AMD64) || \
259 (defined(_M_IX86_FP) && _M_IX86_FP >= 2)
260# define PNG_INTEL_SSE_IMPLEMENTATION 1
261# else
262# define PNG_INTEL_SSE_IMPLEMENTATION 0
263# endif
264# endif
265
266# if PNG_INTEL_SSE_IMPLEMENTATION > 0
267# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_sse2
268# endif
269#else
270# define PNG_INTEL_SSE_IMPLEMENTATION 0
271#endif
272
273#if PNG_MIPS_MSA_OPT > 0
274# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_msa
275# ifndef PNG_MIPS_MSA_IMPLEMENTATION
276# if defined(__mips_msa)
277# if defined(__clang__)
278# elif defined(__GNUC__)
279# if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 7)
280# define PNG_MIPS_MSA_IMPLEMENTATION 2
281# endif /* no GNUC support */
282# endif /* __GNUC__ */
283# else /* !defined __mips_msa */
284# define PNG_MIPS_MSA_IMPLEMENTATION 2
285# endif /* __mips_msa */
286# endif /* !PNG_MIPS_MSA_IMPLEMENTATION */
287
288# ifndef PNG_MIPS_MSA_IMPLEMENTATION
289# define PNG_MIPS_MSA_IMPLEMENTATION 1
290# endif
291#endif /* PNG_MIPS_MSA_OPT > 0 */
292
293#if PNG_POWERPC_VSX_OPT > 0
294# define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_vsx
295# define PNG_POWERPC_VSX_IMPLEMENTATION 1
296#endif
297
298/* Is this a build of a DLL where compilation of the object modules requires
299 * different preprocessor settings to those required for a simple library? If
300 * so PNG_BUILD_DLL must be set.
301 *
302 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
303 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
304 * static library of libpng then link the DLL against that.
305 */
306#ifndef PNG_BUILD_DLL
307# ifdef DLL_EXPORT
308 /* This is set by libtool when files are compiled for a DLL; libtool
309 * always compiles twice, even on systems where it isn't necessary. Set
310 * PNG_BUILD_DLL in case it is necessary:
311 */
312# define PNG_BUILD_DLL
313# else
314# ifdef _WINDLL
315 /* This is set by the Microsoft Visual Studio IDE in projects that
316 * build a DLL. It can't easily be removed from those projects (it
317 * isn't visible in the Visual Studio UI) so it is a fairly reliable
318 * indication that PNG_IMPEXP needs to be set to the DLL export
319 * attributes.
320 */
321# define PNG_BUILD_DLL
322# else
323# ifdef __DLL__
324 /* This is set by the Borland C system when compiling for a DLL
325 * (as above.)
326 */
327# define PNG_BUILD_DLL
328# else
329 /* Add additional compiler cases here. */
330# endif
331# endif
332# endif
333#endif /* Setting PNG_BUILD_DLL if required */
334
335/* See pngconf.h for more details: the builder of the library may set this on
336 * the command line to the right thing for the specific compilation system or it
337 * may be automagically set above (at present we know of no system where it does
338 * need to be set on the command line.)
339 *
340 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
341 * setting it to the "import" setting for a DLL build.
342 */
343#ifndef PNG_IMPEXP
344# ifdef PNG_BUILD_DLL
345# define PNG_IMPEXP PNG_DLL_EXPORT
346# else
347 /* Not building a DLL, or the DLL doesn't require specific export
348 * definitions.
349 */
350# define PNG_IMPEXP
351# endif
352#endif
353
354/* No warnings for private or deprecated functions in the build: */
355#ifndef PNG_DEPRECATED
356# define PNG_DEPRECATED
357#endif
358#ifndef PNG_PRIVATE
359# define PNG_PRIVATE
360#endif
361
362/* Symbol preprocessing support.
363 *
364 * To enable listing global, but internal, symbols the following macros should
365 * always be used to declare an extern data or function object in this file.
366 */
367#ifndef PNG_INTERNAL_DATA
368# define PNG_INTERNAL_DATA(type, name, array) PNG_LINKAGE_DATA type name array
369#endif
370
371#ifndef PNG_INTERNAL_FUNCTION
372# define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
373 PNG_LINKAGE_FUNCTION PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
374#endif
375
376#ifndef PNG_INTERNAL_CALLBACK
377# define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
378 PNG_LINKAGE_CALLBACK PNG_FUNCTION(type, (PNGCBAPI name), args,\
379 PNG_EMPTY attributes)
380#endif
381
382/* If floating or fixed point APIs are disabled they may still be compiled
383 * internally. To handle this make sure they are declared as the appropriate
384 * internal extern function (otherwise the symbol prefixing stuff won't work and
385 * the functions will be used without definitions.)
386 *
387 * NOTE: although all the API functions are declared here they are not all
388 * actually built! Because the declarations are still made it is necessary to
389 * fake out types that they depend on.
390 */
391#ifndef PNG_FP_EXPORT
392# ifndef PNG_FLOATING_POINT_SUPPORTED
393# define PNG_FP_EXPORT(ordinal, type, name, args)\
394 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
395# ifndef PNG_VERSION_INFO_ONLY
396 typedef struct png_incomplete png_double;
397 typedef png_double* png_doublep;
398 typedef const png_double* png_const_doublep;
399 typedef png_double** png_doublepp;
400# endif
401# endif
402#endif
403#ifndef PNG_FIXED_EXPORT
404# ifndef PNG_FIXED_POINT_SUPPORTED
405# define PNG_FIXED_EXPORT(ordinal, type, name, args)\
406 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
407# endif
408#endif
409
410#include "png.h"
411
412/* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
413#ifndef PNG_DLL_EXPORT
414# define PNG_DLL_EXPORT
415#endif
416
417/* This is a global switch to set the compilation for an installed system
418 * (a release build). It can be set for testing debug builds to ensure that
419 * they will compile when the build type is switched to RC or STABLE, the
420 * default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS
421 * with either:
422 *
423 * -DPNG_RELEASE_BUILD Turns on the release compile path
424 * -DPNG_RELEASE_BUILD=0 Turns it off
425 * or in your pngusr.h with
426 * #define PNG_RELEASE_BUILD=1 Turns on the release compile path
427 * #define PNG_RELEASE_BUILD=0 Turns it off
428 */
429#ifndef PNG_RELEASE_BUILD
430# define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC)
431#endif
432
433/* SECURITY and SAFETY:
434 *
435 * libpng is built with support for internal limits on image dimensions and
436 * memory usage. These are documented in scripts/pnglibconf.dfa of the
437 * source and recorded in the machine generated header file pnglibconf.h.
438 */
439
440/* If you are running on a machine where you cannot allocate more
441 * than 64K of memory at once, uncomment this. While libpng will not
442 * normally need that much memory in a chunk (unless you load up a very
443 * large file), zlib needs to know how big of a chunk it can use, and
444 * libpng thus makes sure to check any memory allocation to verify it
445 * will fit into memory.
446 *
447 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
448 * same limit and pngconf.h (already included) sets the limit
449 * if certain operating systems are detected.
450 */
451#if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
452# define PNG_MAX_MALLOC_64K
453#endif
454
455#ifndef PNG_UNUSED
456/* Unused formal parameter warnings are silenced using the following macro
457 * which is expected to have no bad effects on performance (optimizing
458 * compilers will probably remove it entirely). Note that if you replace
459 * it with something other than whitespace, you must include the terminating
460 * semicolon.
461 */
462# define PNG_UNUSED(param) (void)param;
463#endif
464
465/* Just a little check that someone hasn't tried to define something
466 * contradictory.
467 */
468#if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
469# undef PNG_ZBUF_SIZE
470# define PNG_ZBUF_SIZE 65536L
471#endif
472
473/* If warnings or errors are turned off the code is disabled or redirected here.
474 * From 1.5.4 functions have been added to allow very limited formatting of
475 * error and warning messages - this code will also be disabled here.
476 */
477#ifdef PNG_WARNINGS_SUPPORTED
478# define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
479#else
480# define png_warning_parameter(p,number,string) ((void)0)
481# define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
482# define png_warning_parameter_signed(p,number,format,value) ((void)0)
483# define png_formatted_warning(pp,p,message) ((void)(pp))
484# define PNG_WARNING_PARAMETERS(p)
485#endif
486#ifndef PNG_ERROR_TEXT_SUPPORTED
487# define png_fixed_error(s1,s2) png_err(s1)
488#endif
489
490/* Some fixed point APIs are still required even if not exported because
491 * they get used by the corresponding floating point APIs. This magic
492 * deals with this:
493 */
494#ifdef PNG_FIXED_POINT_SUPPORTED
495# define PNGFAPI PNGAPI
496#else
497# define PNGFAPI /* PRIVATE */
498#endif
499
500#ifndef PNG_VERSION_INFO_ONLY
501/* Other defines specific to compilers can go here. Try to keep
502 * them inside an appropriate ifdef/endif pair for portability.
503 */
504
505/* C allows up-casts from (void*) to any pointer and (const void*) to any
506 * pointer to a const object. C++ regards this as a type error and requires an
507 * explicit, static, cast and provides the static_cast<> rune to ensure that
508 * const is not cast away.
509 */
510#ifdef __cplusplus
511# define png_voidcast(type, value) static_cast<type>(value)
512# define png_constcast(type, value) const_cast<type>(value)
513# define png_aligncast(type, value) \
514 static_cast<type>(static_cast<void*>(value))
515# define png_aligncastconst(type, value) \
516 static_cast<type>(static_cast<const void*>(value))
517#else
518# define png_voidcast(type, value) (value)
519# ifdef _WIN64
520# ifdef __GNUC__
521 typedef unsigned long long png_ptruint;
522# else
523 typedef unsigned __int64 png_ptruint;
524# endif
525# else
526 typedef unsigned long png_ptruint;
527# endif
528# define png_constcast(type, value) ((type)(png_ptruint)(const void*)(value))
529# define png_aligncast(type, value) ((void*)(value))
530# define png_aligncastconst(type, value) ((const void*)(value))
531#endif /* __cplusplus */
532
533#if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
534 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
535 /* png.c requires the following ANSI-C constants if the conversion of
536 * floating point to ASCII is implemented therein:
537 *
538 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
539 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
540 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
541 */
542# include <float.h>
543
544# if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
545 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
546 /* We need to check that <math.h> hasn't already been included earlier
547 * as it seems it doesn't agree with <fp.h>, yet we should really use
548 * <fp.h> if possible.
549 */
550# if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
551# include <fp.h>
552# endif
553# else
554# include <math.h>
555# endif
556# if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
557 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
558 * MATH=68881
559 */
560# include <m68881.h>
561# endif
562#endif
563
564/* This provides the non-ANSI (far) memory allocation routines. */
565#if defined(__TURBOC__) && defined(__MSDOS__)
566# include <mem.h>
567# include <alloc.h>
568#endif
569
570#if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
571 defined(_WIN32) || defined(__WIN32__)
572# include <windows.h> /* defines _WINDOWS_ macro */
573#endif
574#endif /* PNG_VERSION_INFO_ONLY */
575
576/* Moved here around 1.5.0beta36 from pngconf.h */
577/* Users may want to use these so they are not private. Any library
578 * functions that are passed far data must be model-independent.
579 */
580
581/* Memory model/platform independent fns */
582#ifndef PNG_ABORT
583# ifdef _WINDOWS_
584# define PNG_ABORT() ExitProcess(0)
585# else
586# define PNG_ABORT() abort()
587# endif
588#endif
589
590/* These macros may need to be architecture dependent. */
591#define PNG_ALIGN_NONE 0 /* do not use data alignment */
592#define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
593#ifdef offsetof
594# define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
595#else
596# define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
597#endif
598#define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
599
600#ifndef PNG_ALIGN_TYPE
601 /* Default to using aligned access optimizations and requiring alignment to a
602 * multiple of the data type size. Override in a compiler specific fashion
603 * if necessary by inserting tests here:
604 */
605# define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
606#endif
607
608#if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
609 /* This is used because in some compiler implementations non-aligned
610 * structure members are supported, so the offsetof approach below fails.
611 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
612 * is good for performance. Do not do this unless you have tested the result
613 * and understand it.
614 */
615# define png_alignof(type) (sizeof (type))
616#else
617# if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
618# define png_alignof(type) offsetof(struct{char c; type t;}, t)
619# else
620# if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
621# define png_alignof(type) (1)
622# endif
623 /* Else leave png_alignof undefined to prevent use thereof */
624# endif
625#endif
626
627/* This implicitly assumes alignment is always to a power of 2. */
628#ifdef png_alignof
629# define png_isaligned(ptr, type)\
630 (((type)((const char*)ptr-(const char*)0) & \
631 (type)(png_alignof(type)-1)) == 0)
632#else
633# define png_isaligned(ptr, type) 0
634#endif
635
636/* End of memory model/platform independent support */
637/* End of 1.5.0beta36 move from pngconf.h */
638
639/* CONSTANTS and UTILITY MACROS
640 * These are used internally by libpng and not exposed in the API
641 */
642
643/* Various modes of operation. Note that after an init, mode is set to
644 * zero automatically when the structure is created. Three of these
645 * are defined in png.h because they need to be visible to applications
646 * that call png_set_unknown_chunk().
647 */
648/* #define PNG_HAVE_IHDR 0x01U (defined in png.h) */
649/* #define PNG_HAVE_PLTE 0x02U (defined in png.h) */
650#define PNG_HAVE_IDAT 0x04U
651/* #define PNG_AFTER_IDAT 0x08U (defined in png.h) */
652#define PNG_HAVE_IEND 0x10U
653 /* 0x20U (unused) */
654 /* 0x40U (unused) */
655 /* 0x80U (unused) */
656#define PNG_HAVE_CHUNK_HEADER 0x100U
657#define PNG_WROTE_tIME 0x200U
658#define PNG_WROTE_INFO_BEFORE_PLTE 0x400U
659#define PNG_BACKGROUND_IS_GRAY 0x800U
660#define PNG_HAVE_PNG_SIGNATURE 0x1000U
661#define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000U /* Have another chunk after IDAT */
662 /* 0x4000U (unused) */
663#define PNG_IS_READ_STRUCT 0x8000U /* Else is a write struct */
664
665/* Flags for the transformations the PNG library does on the image data */
666#define PNG_BGR 0x0001U
667#define PNG_INTERLACE 0x0002U
668#define PNG_PACK 0x0004U
669#define PNG_SHIFT 0x0008U
670#define PNG_SWAP_BYTES 0x0010U
671#define PNG_INVERT_MONO 0x0020U
672#define PNG_QUANTIZE 0x0040U
673#define PNG_COMPOSE 0x0080U /* Was PNG_BACKGROUND */
674#define PNG_BACKGROUND_EXPAND 0x0100U
675#define PNG_EXPAND_16 0x0200U /* Added to libpng 1.5.2 */
676#define PNG_16_TO_8 0x0400U /* Becomes 'chop' in 1.5.4 */
677#define PNG_RGBA 0x0800U
678#define PNG_EXPAND 0x1000U
679#define PNG_GAMMA 0x2000U
680#define PNG_GRAY_TO_RGB 0x4000U
681#define PNG_FILLER 0x8000U
682#define PNG_PACKSWAP 0x10000U
683#define PNG_SWAP_ALPHA 0x20000U
684#define PNG_STRIP_ALPHA 0x40000U
685#define PNG_INVERT_ALPHA 0x80000U
686#define PNG_USER_TRANSFORM 0x100000U
687#define PNG_RGB_TO_GRAY_ERR 0x200000U
688#define PNG_RGB_TO_GRAY_WARN 0x400000U
689#define PNG_RGB_TO_GRAY 0x600000U /* two bits, RGB_TO_GRAY_ERR|WARN */
690#define PNG_ENCODE_ALPHA 0x800000U /* Added to libpng-1.5.4 */
691#define PNG_ADD_ALPHA 0x1000000U /* Added to libpng-1.2.7 */
692#define PNG_EXPAND_tRNS 0x2000000U /* Added to libpng-1.2.9 */
693#define PNG_SCALE_16_TO_8 0x4000000U /* Added to libpng-1.5.4 */
694 /* 0x8000000U unused */
695 /* 0x10000000U unused */
696 /* 0x20000000U unused */
697 /* 0x40000000U unused */
698/* Flags for png_create_struct */
699#define PNG_STRUCT_PNG 0x0001U
700#define PNG_STRUCT_INFO 0x0002U
701
702/* Flags for the png_ptr->flags rather than declaring a byte for each one */
703#define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001U
704#define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002U /* Added to libpng-1.6.0 */
705 /* 0x0004U unused */
706#define PNG_FLAG_ZSTREAM_ENDED 0x0008U /* Added to libpng-1.6.0 */
707 /* 0x0010U unused */
708 /* 0x0020U unused */
709#define PNG_FLAG_ROW_INIT 0x0040U
710#define PNG_FLAG_FILLER_AFTER 0x0080U
711#define PNG_FLAG_CRC_ANCILLARY_USE 0x0100U
712#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200U
713#define PNG_FLAG_CRC_CRITICAL_USE 0x0400U
714#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800U
715#define PNG_FLAG_ASSUME_sRGB 0x1000U /* Added to libpng-1.5.4 */
716#define PNG_FLAG_OPTIMIZE_ALPHA 0x2000U /* Added to libpng-1.5.4 */
717#define PNG_FLAG_DETECT_UNINITIALIZED 0x4000U /* Added to libpng-1.5.4 */
718/* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000U */
719/* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000U */
720#define PNG_FLAG_LIBRARY_MISMATCH 0x20000U
721#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000U
722#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000U
723#define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000U /* Added to libpng-1.4.0 */
724#define PNG_FLAG_APP_WARNINGS_WARN 0x200000U /* Added to libpng-1.6.0 */
725#define PNG_FLAG_APP_ERRORS_WARN 0x400000U /* Added to libpng-1.6.0 */
726 /* 0x800000U unused */
727 /* 0x1000000U unused */
728 /* 0x2000000U unused */
729 /* 0x4000000U unused */
730 /* 0x8000000U unused */
731 /* 0x10000000U unused */
732 /* 0x20000000U unused */
733 /* 0x40000000U unused */
734
735#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
736 PNG_FLAG_CRC_ANCILLARY_NOWARN)
737
738#define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
739 PNG_FLAG_CRC_CRITICAL_IGNORE)
740
741#define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
742 PNG_FLAG_CRC_CRITICAL_MASK)
743
744/* Save typing and make code easier to understand */
745
746#define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
747 abs((int)((c1).green) - (int)((c2).green)) + \
748 abs((int)((c1).blue) - (int)((c2).blue)))
749
750/* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
751 * by dividing by 257 *with rounding*. This macro is exact for the given range.
752 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the
753 * macro were established by experiment (modifying the added value). The macro
754 * has a second variant that takes a value already scaled by 255 and divides by
755 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it
756 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
757 */
758#define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
759#define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
760
761/* Added to libpng-1.2.6 JB */
762#define PNG_ROWBYTES(pixel_bits, width) \
763 ((pixel_bits) >= 8 ? \
764 ((size_t)(width) * (((size_t)(pixel_bits)) >> 3)) : \
765 (( ((size_t)(width) * ((size_t)(pixel_bits))) + 7) >> 3) )
766
767/* This returns the number of trailing bits in the last byte of a row, 0 if the
768 * last byte is completely full of pixels. It is, in principle, (pixel_bits x
769 * width) % 8, but that would overflow for large 'width'. The second macro is
770 * the same except that it returns the number of unused bits in the last byte;
771 * (8-TRAILBITS), but 0 when TRAILBITS is 0.
772 *
773 * NOTE: these macros are intended to be self-evidently correct and never
774 * overflow on the assumption that pixel_bits is in the range 0..255. The
775 * arguments are evaluated only once and they can be signed (e.g. as a result of
776 * the integral promotions). The result of the expression always has type
777 * (png_uint_32), however the compiler always knows it is in the range 0..7.
778 */
779#define PNG_TRAILBITS(pixel_bits, width) \
780 (((pixel_bits) * ((width) % (png_uint_32)8)) % 8)
781
782#define PNG_PADBITS(pixel_bits, width) \
783 ((8 - PNG_TRAILBITS(pixel_bits, width)) % 8)
784
785/* PNG_OUT_OF_RANGE returns true if value is outside the range
786 * ideal-delta..ideal+delta. Each argument is evaluated twice.
787 * "ideal" and "delta" should be constants, normally simple
788 * integers, "value" a variable. Added to libpng-1.2.6 JB
789 */
790#define PNG_OUT_OF_RANGE(value, ideal, delta) \
791 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
792
793/* Conversions between fixed and floating point, only defined if
794 * required (to make sure the code doesn't accidentally use float
795 * when it is supposedly disabled.)
796 */
797#ifdef PNG_FLOATING_POINT_SUPPORTED
798/* The floating point conversion can't overflow, though it can and
799 * does lose accuracy relative to the original fixed point value.
800 * In practice this doesn't matter because png_fixed_point only
801 * stores numbers with very low precision. The png_ptr and s
802 * arguments are unused by default but are there in case error
803 * checking becomes a requirement.
804 */
805#define png_float(png_ptr, fixed, s) (.00001 * (fixed))
806
807/* The fixed point conversion performs range checking and evaluates
808 * its argument multiple times, so must be used with care. The
809 * range checking uses the PNG specification values for a signed
810 * 32-bit fixed point value except that the values are deliberately
811 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
812 * (2^31-1) * 100000). 's' is a string that describes the value being
813 * converted.
814 *
815 * NOTE: this macro will raise a png_error if the range check fails,
816 * therefore it is normally only appropriate to use this on values
817 * that come from API calls or other sources where an out of range
818 * error indicates a programming error, not a data error!
819 *
820 * NOTE: by default this is off - the macro is not used - because the
821 * function call saves a lot of code.
822 */
823#ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
824#define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
825 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
826#endif
827/* else the corresponding function is defined below, inside the scope of the
828 * cplusplus test.
829 */
830#endif
831
832/* Constants for known chunk types. If you need to add a chunk, define the name
833 * here. For historical reasons these constants have the form png_<name>; i.e.
834 * the prefix is lower case. Please use decimal values as the parameters to
835 * match the ISO PNG specification and to avoid relying on the C locale
836 * interpretation of character values.
837 *
838 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
839 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
840 * to be generated if required.
841 *
842 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
843 * architectures where (int) is only 16 bits.
844 */
845#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
846#define PNG_U32(b1,b2,b3,b4) \
847 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
848
849/* Constants for known chunk types.
850 *
851 * MAINTAINERS: If you need to add a chunk, define the name here.
852 * For historical reasons these constants have the form png_<name>; i.e.
853 * the prefix is lower case. Please use decimal values as the parameters to
854 * match the ISO PNG specification and to avoid relying on the C locale
855 * interpretation of character values. Please keep the list sorted.
856 *
857 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
858 * type. In fact the specification does not express chunk types this way,
859 * however using a 32-bit value means that the chunk type can be read from the
860 * stream using exactly the same code as used for a 32-bit unsigned value and
861 * can be examined far more efficiently (using one arithmetic compare).
862 *
863 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The
864 * libpng API still uses strings for 'unknown' chunks and a macro,
865 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice
866 * that for portable code numeric values must still be used; the string "IHDR"
867 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
868 *
869 * In 1.7.0 the definitions will be made public in png.h to avoid having to
870 * duplicate the same definitions in application code.
871 */
872#define png_IDAT PNG_U32( 73, 68, 65, 84)
873#define png_IEND PNG_U32( 73, 69, 78, 68)
874#define png_IHDR PNG_U32( 73, 72, 68, 82)
875#define png_PLTE PNG_U32( 80, 76, 84, 69)
876#define png_bKGD PNG_U32( 98, 75, 71, 68)
877#define png_cHRM PNG_U32( 99, 72, 82, 77)
878#define png_eXIf PNG_U32(101, 88, 73, 102) /* registered July 2017 */
879#define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
880#define png_gAMA PNG_U32(103, 65, 77, 65)
881#define png_gIFg PNG_U32(103, 73, 70, 103)
882#define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
883#define png_gIFx PNG_U32(103, 73, 70, 120)
884#define png_hIST PNG_U32(104, 73, 83, 84)
885#define png_iCCP PNG_U32(105, 67, 67, 80)
886#define png_iTXt PNG_U32(105, 84, 88, 116)
887#define png_oFFs PNG_U32(111, 70, 70, 115)
888#define png_pCAL PNG_U32(112, 67, 65, 76)
889#define png_pHYs PNG_U32(112, 72, 89, 115)
890#define png_sBIT PNG_U32(115, 66, 73, 84)
891#define png_sCAL PNG_U32(115, 67, 65, 76)
892#define png_sPLT PNG_U32(115, 80, 76, 84)
893#define png_sRGB PNG_U32(115, 82, 71, 66)
894#define png_sTER PNG_U32(115, 84, 69, 82)
895#define png_tEXt PNG_U32(116, 69, 88, 116)
896#define png_tIME PNG_U32(116, 73, 77, 69)
897#define png_tRNS PNG_U32(116, 82, 78, 83)
898#define png_zTXt PNG_U32(122, 84, 88, 116)
899
900/* The following will work on (signed char*) strings, whereas the get_uint_32
901 * macro will fail on top-bit-set values because of the sign extension.
902 */
903#define PNG_CHUNK_FROM_STRING(s)\
904 PNG_U32(0xff & (s)[0], 0xff & (s)[1], 0xff & (s)[2], 0xff & (s)[3])
905
906/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
907 * signed and the argument is a (char[]) This macro will fail miserably on
908 * systems where (char) is more than 8 bits.
909 */
910#define PNG_STRING_FROM_CHUNK(s,c)\
911 (void)(((char*)(s))[0]=(char)(((c)>>24) & 0xff), \
912 ((char*)(s))[1]=(char)(((c)>>16) & 0xff),\
913 ((char*)(s))[2]=(char)(((c)>>8) & 0xff), \
914 ((char*)(s))[3]=(char)((c & 0xff)))
915
916/* Do the same but terminate with a null character. */
917#define PNG_CSTRING_FROM_CHUNK(s,c)\
918 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
919
920/* Test on flag values as defined in the spec (section 5.4): */
921#define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
922#define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
923#define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
924#define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
925#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
926
927/* Gamma values (new at libpng-1.5.4): */
928#define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
929#define PNG_GAMMA_MAC_INVERSE 65909
930#define PNG_GAMMA_sRGB_INVERSE 45455
931
932/* Almost everything below is C specific; the #defines above can be used in
933 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
934 */
935#ifndef PNG_VERSION_INFO_ONLY
936
937#include "pngstruct.h"
938#include "pnginfo.h"
939
940/* Validate the include paths - the include path used to generate pnglibconf.h
941 * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
942 */
943#if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
944# error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
945 "-I (include path) error: see the notes in pngpriv.h"
946 /* This means that when pnglibconf.h was built the copy of zlib.h that it
947 * used is not the same as the one being used here. Because the build of
948 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
949 * zlib version number and because this affects handling of certain broken
950 * PNG files the -I directives must match.
951 *
952 * The most likely explanation is that you passed a -I in CFLAGS. This will
953 * not work; all the preprocessor directives and in particular all the -I
954 * directives must be in CPPFLAGS.
955 */
956#endif
957
958/* This is used for 16-bit gamma tables -- only the top level pointers are
959 * const; this could be changed:
960 */
961typedef const png_uint_16p * png_const_uint_16pp;
962
963/* Added to libpng-1.5.7: sRGB conversion tables */
964#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
965 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
966#ifdef PNG_SIMPLIFIED_READ_SUPPORTED
967PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
968 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
969 * 0..65535. This table gives the closest 16-bit answers (no errors).
970 */
971#endif
972
973PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
974PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
975
976#define PNG_sRGB_FROM_LINEAR(linear) \
977 ((png_byte)(0xff & ((png_sRGB_base[(linear)>>15] \
978 + ((((linear) & 0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8)))
979 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
980 * encoded value with maximum error 0.646365. Note that the input is not a
981 * 16-bit value; it has been multiplied by 255! */
982#endif /* SIMPLIFIED_READ/WRITE */
983
984
985/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
986#ifdef __cplusplus
987extern "C" {
988#endif /* __cplusplus */
989
990/* Internal functions; these are not exported from a DLL however because they
991 * are used within several of the C source files they have to be C extern.
992 *
993 * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
994 */
995
996/* Zlib support */
997#define PNG_UNEXPECTED_ZLIB_RETURN (-7)
998PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
999 PNG_EMPTY);
1000 /* Used by the zlib handling functions to ensure that z_stream::msg is always
1001 * set before they return.
1002 */
1003
1004#ifdef PNG_WRITE_SUPPORTED
1005PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
1006 png_compression_bufferp *list),PNG_EMPTY);
1007 /* Free the buffer list used by the compressed write code. */
1008#endif
1009
1010#if defined(PNG_FLOATING_POINT_SUPPORTED) && \
1011 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
1012 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
1013 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
1014 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
1015 (defined(PNG_sCAL_SUPPORTED) && \
1016 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
1017PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
1018 double fp, png_const_charp text),PNG_EMPTY);
1019#endif
1020
1021/* Check the user version string for compatibility, returns false if the version
1022 * numbers aren't compatible.
1023 */
1024PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
1025 png_const_charp user_png_ver),PNG_EMPTY);
1026
1027/* Internal base allocator - no messages, NULL on failure to allocate. This
1028 * does, however, call the application provided allocator and that could call
1029 * png_error (although that would be a bug in the application implementation.)
1030 */
1031PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
1032 png_alloc_size_t size),PNG_ALLOCATED);
1033
1034#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
1035 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
1036/* Internal array allocator, outputs no error or warning messages on failure,
1037 * just returns NULL.
1038 */
1039PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
1040 int nelements, size_t element_size),PNG_ALLOCATED);
1041
1042/* The same but an existing array is extended by add_elements. This function
1043 * also memsets the new elements to 0 and copies the old elements. The old
1044 * array is not freed or altered.
1045 */
1046PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
1047 png_const_voidp array, int old_elements, int add_elements,
1048 size_t element_size),PNG_ALLOCATED);
1049#endif /* text, sPLT or unknown chunks */
1050
1051/* Magic to create a struct when there is no struct to call the user supplied
1052 * memory allocators. Because error handling has not been set up the memory
1053 * handlers can't safely call png_error, but this is an obscure and undocumented
1054 * restriction so libpng has to assume that the 'free' handler, at least, might
1055 * call png_error.
1056 */
1057PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
1058 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
1059 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
1060 png_free_ptr free_fn),PNG_ALLOCATED);
1061
1062/* Free memory from internal libpng struct */
1063PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
1064 PNG_EMPTY);
1065
1066/* Free an allocated jmp_buf (always succeeds) */
1067PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
1068
1069/* Function to allocate memory for zlib. PNGAPI is disallowed. */
1070PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
1071 PNG_ALLOCATED);
1072
1073/* Function to free memory for zlib. PNGAPI is disallowed. */
1074PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
1075
1076/* Next four functions are used internally as callbacks. PNGCBAPI is required
1077 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
1078 * PNGCBAPI at 1.5.0
1079 */
1080
1081PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
1082 png_bytep data, size_t length),PNG_EMPTY);
1083
1084#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1085PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
1086 png_bytep buffer, size_t length),PNG_EMPTY);
1087#endif
1088
1089PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
1090 png_bytep data, size_t length),PNG_EMPTY);
1091
1092#ifdef PNG_WRITE_FLUSH_SUPPORTED
1093# ifdef PNG_STDIO_SUPPORTED
1094PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
1095 PNG_EMPTY);
1096# endif
1097#endif
1098
1099/* Reset the CRC variable */
1100PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
1101
1102/* Write the "data" buffer to whatever output you are using */
1103PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
1104 png_const_bytep data, size_t length),PNG_EMPTY);
1105
1106/* Read and check the PNG file signature */
1107PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
1108 png_inforp info_ptr),PNG_EMPTY);
1109
1110/* Read the chunk header (length + type name) */
1111PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
1112 PNG_EMPTY);
1113
1114/* Read data from whatever input you are using into the "data" buffer */
1115PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
1116 size_t length),PNG_EMPTY);
1117
1118/* Read bytes into buf, and update png_ptr->crc */
1119PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
1120 png_uint_32 length),PNG_EMPTY);
1121
1122/* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
1123PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
1124 png_uint_32 skip),PNG_EMPTY);
1125
1126/* Read the CRC from the file and compare it to the libpng calculated CRC */
1127PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
1128
1129/* Calculate the CRC over a section of data. Note that we are only
1130 * passing a maximum of 64K on systems that have this as a memory limit,
1131 * since this is the maximum buffer size we can specify.
1132 */
1133PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
1134 png_const_bytep ptr, size_t length),PNG_EMPTY);
1135
1136#ifdef PNG_WRITE_FLUSH_SUPPORTED
1137PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
1138#endif
1139
1140/* Write various chunks */
1141
1142/* Write the IHDR chunk, and update the png_struct with the necessary
1143 * information.
1144 */
1145PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
1146 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
1147 int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
1148
1149PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
1150 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
1151
1152PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
1153 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
1154 PNG_EMPTY);
1155
1156PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
1157
1158#ifdef PNG_WRITE_gAMA_SUPPORTED
1159PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
1160 png_fixed_point file_gamma),PNG_EMPTY);
1161#endif
1162
1163#ifdef PNG_WRITE_sBIT_SUPPORTED
1164PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
1165 png_const_color_8p sbit, int color_type),PNG_EMPTY);
1166#endif
1167
1168#ifdef PNG_WRITE_cHRM_SUPPORTED
1169PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
1170 const png_xy *xy), PNG_EMPTY);
1171 /* The xy value must have been previously validated */
1172#endif
1173
1174#ifdef PNG_WRITE_sRGB_SUPPORTED
1175PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
1176 int intent),PNG_EMPTY);
1177#endif
1178
1179#ifdef PNG_WRITE_eXIf_SUPPORTED
1180PNG_INTERNAL_FUNCTION(void,png_write_eXIf,(png_structrp png_ptr,
1181 png_bytep exif, int num_exif),PNG_EMPTY);
1182#endif
1183
1184#ifdef PNG_WRITE_iCCP_SUPPORTED
1185PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
1186 png_const_charp name, png_const_bytep profile), PNG_EMPTY);
1187 /* The profile must have been previously validated for correctness, the
1188 * length comes from the first four bytes. Only the base, deflate,
1189 * compression is supported.
1190 */
1191#endif
1192
1193#ifdef PNG_WRITE_sPLT_SUPPORTED
1194PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
1195 png_const_sPLT_tp palette),PNG_EMPTY);
1196#endif
1197
1198#ifdef PNG_WRITE_tRNS_SUPPORTED
1199PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
1200 png_const_bytep trans, png_const_color_16p values, int number,
1201 int color_type),PNG_EMPTY);
1202#endif
1203
1204#ifdef PNG_WRITE_bKGD_SUPPORTED
1205PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
1206 png_const_color_16p values, int color_type),PNG_EMPTY);
1207#endif
1208
1209#ifdef PNG_WRITE_hIST_SUPPORTED
1210PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
1211 png_const_uint_16p hist, int num_hist),PNG_EMPTY);
1212#endif
1213
1214/* Chunks that have keywords */
1215#ifdef PNG_WRITE_tEXt_SUPPORTED
1216PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
1217 png_const_charp key, png_const_charp text, size_t text_len),PNG_EMPTY);
1218#endif
1219
1220#ifdef PNG_WRITE_zTXt_SUPPORTED
1221PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
1222 key, png_const_charp text, int compression),PNG_EMPTY);
1223#endif
1224
1225#ifdef PNG_WRITE_iTXt_SUPPORTED
1226PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
1227 int compression, png_const_charp key, png_const_charp lang,
1228 png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
1229#endif
1230
1231#ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
1232PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
1233 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
1234#endif
1235
1236#ifdef PNG_WRITE_oFFs_SUPPORTED
1237PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
1238 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
1239#endif
1240
1241#ifdef PNG_WRITE_pCAL_SUPPORTED
1242PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
1243 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
1244 png_const_charp units, png_charpp params),PNG_EMPTY);
1245#endif
1246
1247#ifdef PNG_WRITE_pHYs_SUPPORTED
1248PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
1249 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
1250 int unit_type),PNG_EMPTY);
1251#endif
1252
1253#ifdef PNG_WRITE_tIME_SUPPORTED
1254PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
1255 png_const_timep mod_time),PNG_EMPTY);
1256#endif
1257
1258#ifdef PNG_WRITE_sCAL_SUPPORTED
1259PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
1260 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
1261#endif
1262
1263/* Called when finished processing a row of data */
1264PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
1265 PNG_EMPTY);
1266
1267/* Internal use only. Called before first row of data */
1268PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
1269 PNG_EMPTY);
1270
1271/* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
1272 * array of png_ptr->width pixels. If the image is not interlaced or this
1273 * is the final pass this just does a memcpy, otherwise the "display" flag
1274 * is used to determine whether to copy pixels that are not in the current pass.
1275 *
1276 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
1277 * function to achieve the documented 'blocky' appearance during interlaced read
1278 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
1279 * are not changed if they are not in the current pass, when display is 0.
1280 *
1281 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
1282 *
1283 * The API always reads from the png_struct row buffer and always assumes that
1284 * it is full width (png_do_read_interlace has already been called.)
1285 *
1286 * This function is only ever used to write to row buffers provided by the
1287 * caller of the relevant libpng API and the row must have already been
1288 * transformed by the read transformations.
1289 *
1290 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
1291 * bitmasks for use within the code, otherwise runtime generated masks are used.
1292 * The default is compile time masks.
1293 */
1294#ifndef PNG_USE_COMPILE_TIME_MASKS
1295# define PNG_USE_COMPILE_TIME_MASKS 1
1296#endif
1297PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
1298 png_bytep row, int display),PNG_EMPTY);
1299
1300#ifdef PNG_READ_INTERLACING_SUPPORTED
1301/* Expand an interlaced row: the 'row_info' describes the pass data that has
1302 * been read in and must correspond to the pixels in 'row', the pixels are
1303 * expanded (moved apart) in 'row' to match the final layout, when doing this
1304 * the pixels are *replicated* to the intervening space. This is essential for
1305 * the correct operation of png_combine_row, above.
1306 */
1307PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
1308 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
1309#endif
1310
1311/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
1312
1313#ifdef PNG_WRITE_INTERLACING_SUPPORTED
1314/* Grab pixels out of a row for an interlaced pass */
1315PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
1316 png_bytep row, int pass),PNG_EMPTY);
1317#endif
1318
1319/* Unfilter a row: check the filter value before calling this, there is no point
1320 * calling it for PNG_FILTER_VALUE_NONE.
1321 */
1322PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
1323 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
1324
1325#if PNG_ARM_NEON_OPT > 0
1326PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
1327 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1328PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
1329 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1330PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
1331 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1332PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
1333 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1334PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_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_paeth3_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_paeth4_neon,(png_row_infop
1339 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1340#endif
1341
1342#if PNG_MIPS_MSA_OPT > 0
1343PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_msa,(png_row_infop row_info,
1344 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1345PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_msa,(png_row_infop
1346 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1347PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_msa,(png_row_infop
1348 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1349PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_msa,(png_row_infop
1350 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1351PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_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_paeth3_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_paeth4_msa,(png_row_infop
1356 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1357#endif
1358
1359#if PNG_POWERPC_VSX_OPT > 0
1360PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_vsx,(png_row_infop row_info,
1361 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1362PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_vsx,(png_row_infop
1363 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1364PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_vsx,(png_row_infop
1365 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1366PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_vsx,(png_row_infop
1367 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1368PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_vsx,(png_row_infop
1369 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1370PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_vsx,(png_row_infop
1371 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1372PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_vsx,(png_row_infop
1373 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1374#endif
1375
1376#if PNG_INTEL_SSE_IMPLEMENTATION > 0
1377PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_sse2,(png_row_infop
1378 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1379PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_sse2,(png_row_infop
1380 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1381PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_sse2,(png_row_infop
1382 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1383PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_sse2,(png_row_infop
1384 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1385PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_sse2,(png_row_infop
1386 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1387PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_sse2,(png_row_infop
1388 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1389#endif
1390
1391/* Choose the best filter to use and filter the row data */
1392PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
1393 png_row_infop row_info),PNG_EMPTY);
1394
1395#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1396PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
1397 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
1398 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer
1399 * is NULL the function checks, instead, for the end of the stream. In this
1400 * case a benign error will be issued if the stream end is not found or if
1401 * extra data has to be consumed.
1402 */
1403PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
1404 PNG_EMPTY);
1405 /* This cleans up when the IDAT LZ stream does not end when the last image
1406 * byte is read; there is still some pending input.
1407 */
1408
1409PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
1410 PNG_EMPTY);
1411 /* Finish a row while reading, dealing with interlacing passes, etc. */
1412#endif /* SEQUENTIAL_READ */
1413
1414/* Initialize the row buffers, etc. */
1415PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
1416
1417#if ZLIB_VERNUM >= 0x1240
1418PNG_INTERNAL_FUNCTION(int,png_zlib_inflate,(png_structrp png_ptr, int flush),
1419 PNG_EMPTY);
1420# define PNG_INFLATE(pp, flush) png_zlib_inflate(pp, flush)
1421#else /* Zlib < 1.2.4 */
1422# define PNG_INFLATE(pp, flush) inflate(&(pp)->zstream, flush)
1423#endif /* Zlib < 1.2.4 */
1424
1425#ifdef PNG_READ_TRANSFORMS_SUPPORTED
1426/* Optional call to update the users info structure */
1427PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
1428 png_inforp info_ptr),PNG_EMPTY);
1429#endif
1430
1431/* Shared transform functions, defined in pngtran.c */
1432#if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1433 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1434PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
1435 png_bytep row, int at_start),PNG_EMPTY);
1436#endif
1437
1438#ifdef PNG_16BIT_SUPPORTED
1439#if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1440PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
1441 png_bytep row),PNG_EMPTY);
1442#endif
1443#endif
1444
1445#if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1446 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1447PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
1448 png_bytep row),PNG_EMPTY);
1449#endif
1450
1451#if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1452PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
1453 png_bytep row),PNG_EMPTY);
1454#endif
1455
1456#if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1457PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
1458 png_bytep row),PNG_EMPTY);
1459#endif
1460
1461/* The following decodes the appropriate chunks, and does error correction,
1462 * then calls the appropriate callback for the chunk if it is valid.
1463 */
1464
1465/* Decode the IHDR chunk */
1466PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
1467 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1468PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
1469 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1470PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
1471 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1472
1473#ifdef PNG_READ_bKGD_SUPPORTED
1474PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
1475 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1476#endif
1477
1478#ifdef PNG_READ_cHRM_SUPPORTED
1479PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
1480 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1481#endif
1482
1483#ifdef PNG_READ_eXIf_SUPPORTED
1484PNG_INTERNAL_FUNCTION(void,png_handle_eXIf,(png_structrp png_ptr,
1485 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1486#endif
1487
1488#ifdef PNG_READ_gAMA_SUPPORTED
1489PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
1490 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1491#endif
1492
1493#ifdef PNG_READ_hIST_SUPPORTED
1494PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
1495 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1496#endif
1497
1498#ifdef PNG_READ_iCCP_SUPPORTED
1499PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
1500 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1501#endif /* READ_iCCP */
1502
1503#ifdef PNG_READ_iTXt_SUPPORTED
1504PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
1505 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1506#endif
1507
1508#ifdef PNG_READ_oFFs_SUPPORTED
1509PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
1510 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1511#endif
1512
1513#ifdef PNG_READ_pCAL_SUPPORTED
1514PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
1515 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1516#endif
1517
1518#ifdef PNG_READ_pHYs_SUPPORTED
1519PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
1520 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1521#endif
1522
1523#ifdef PNG_READ_sBIT_SUPPORTED
1524PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
1525 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1526#endif
1527
1528#ifdef PNG_READ_sCAL_SUPPORTED
1529PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
1530 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1531#endif
1532
1533#ifdef PNG_READ_sPLT_SUPPORTED
1534PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
1535 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1536#endif /* READ_sPLT */
1537
1538#ifdef PNG_READ_sRGB_SUPPORTED
1539PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
1540 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1541#endif
1542
1543#ifdef PNG_READ_tEXt_SUPPORTED
1544PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
1545 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1546#endif
1547
1548#ifdef PNG_READ_tIME_SUPPORTED
1549PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
1550 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1551#endif
1552
1553#ifdef PNG_READ_tRNS_SUPPORTED
1554PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
1555 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1556#endif
1557
1558#ifdef PNG_READ_zTXt_SUPPORTED
1559PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
1560 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1561#endif
1562
1563PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_const_structrp png_ptr,
1564 const png_uint_32 chunk_name),PNG_EMPTY);
1565
1566PNG_INTERNAL_FUNCTION(void,png_check_chunk_length,(png_const_structrp png_ptr,
1567 const png_uint_32 chunk_length),PNG_EMPTY);
1568
1569PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
1570 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
1571 /* This is the function that gets called for unknown chunks. The 'keep'
1572 * argument is either non-zero for a known chunk that has been set to be
1573 * handled as unknown or zero for an unknown chunk. By default the function
1574 * just skips the chunk or errors out if it is critical.
1575 */
1576
1577#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
1578 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
1579PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
1580 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
1581 /* Exactly as the API png_handle_as_unknown() except that the argument is a
1582 * 32-bit chunk name, not a string.
1583 */
1584#endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
1585
1586/* Handle the transformations for reading and writing */
1587#ifdef PNG_READ_TRANSFORMS_SUPPORTED
1588PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
1589 png_row_infop row_info),PNG_EMPTY);
1590#endif
1591#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1592PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
1593 png_row_infop row_info),PNG_EMPTY);
1594#endif
1595
1596#ifdef PNG_READ_TRANSFORMS_SUPPORTED
1597PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
1598 PNG_EMPTY);
1599#endif
1600
1601#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1602PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
1603 png_inforp info_ptr),PNG_EMPTY);
1604PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
1605 png_inforp info_ptr),PNG_EMPTY);
1606PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
1607PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
1608 PNG_EMPTY);
1609PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
1610 png_bytep buffer, size_t buffer_length),PNG_EMPTY);
1611PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
1612PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
1613 png_bytep buffer, size_t buffer_length),PNG_EMPTY);
1614PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
1615 PNG_EMPTY);
1616PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
1617 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1618PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
1619 png_inforp info_ptr),PNG_EMPTY);
1620PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
1621 png_inforp info_ptr),PNG_EMPTY);
1622PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
1623 png_bytep row),PNG_EMPTY);
1624PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
1625 png_inforp info_ptr),PNG_EMPTY);
1626PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
1627 png_inforp info_ptr),PNG_EMPTY);
1628PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
1629 PNG_EMPTY);
1630# ifdef PNG_READ_tEXt_SUPPORTED
1631PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
1632 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1633PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
1634 png_inforp info_ptr),PNG_EMPTY);
1635# endif
1636# ifdef PNG_READ_zTXt_SUPPORTED
1637PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
1638 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1639PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
1640 png_inforp info_ptr),PNG_EMPTY);
1641# endif
1642# ifdef PNG_READ_iTXt_SUPPORTED
1643PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
1644 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1645PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
1646 png_inforp info_ptr),PNG_EMPTY);
1647# endif
1648
1649#endif /* PROGRESSIVE_READ */
1650
1651/* Added at libpng version 1.6.0 */
1652#ifdef PNG_GAMMA_SUPPORTED
1653PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
1654 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
1655 /* Set the colorspace gamma with a value provided by the application or by
1656 * the gAMA chunk on read. The value will override anything set by an ICC
1657 * profile.
1658 */
1659
1660PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
1661 png_inforp info_ptr), PNG_EMPTY);
1662 /* Synchronize the info 'valid' flags with the colorspace */
1663
1664PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
1665 png_inforp info_ptr), PNG_EMPTY);
1666 /* Copy the png_struct colorspace to the info_struct and call the above to
1667 * synchronize the flags. Checks for NULL info_ptr and does nothing.
1668 */
1669#endif
1670
1671/* Added at libpng version 1.4.0 */
1672#ifdef PNG_COLORSPACE_SUPPORTED
1673/* These internal functions are for maintaining the colorspace structure within
1674 * a png_info or png_struct (or, indeed, both).
1675 */
1676PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
1677 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
1678 int preferred), PNG_EMPTY);
1679
1680PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
1681 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
1682 int preferred), PNG_EMPTY);
1683
1684#ifdef PNG_sRGB_SUPPORTED
1685PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
1686 png_colorspacerp colorspace, int intent), PNG_EMPTY);
1687 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
1688 * flags to write them, if it returns false there was a problem and an error
1689 * message has already been output (but the colorspace may still need to be
1690 * synced to record the invalid flag).
1691 */
1692#endif /* sRGB */
1693
1694#ifdef PNG_iCCP_SUPPORTED
1695PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
1696 png_colorspacerp colorspace, png_const_charp name,
1697 png_uint_32 profile_length, png_const_bytep profile, int color_type),
1698 PNG_EMPTY);
1699 /* The 'name' is used for information only */
1700
1701/* Routines for checking parts of an ICC profile. */
1702#ifdef PNG_READ_iCCP_SUPPORTED
1703PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
1704 png_colorspacerp colorspace, png_const_charp name,
1705 png_uint_32 profile_length), PNG_EMPTY);
1706#endif /* READ_iCCP */
1707PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
1708 png_colorspacerp colorspace, png_const_charp name,
1709 png_uint_32 profile_length,
1710 png_const_bytep profile /* first 132 bytes only */, int color_type),
1711 PNG_EMPTY);
1712PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
1713 png_colorspacerp colorspace, png_const_charp name,
1714 png_uint_32 profile_length,
1715 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
1716#ifdef PNG_sRGB_SUPPORTED
1717PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
1718 png_const_structrp png_ptr, png_colorspacerp colorspace,
1719 png_const_bytep profile, uLong adler), PNG_EMPTY);
1720 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
1721 * be zero to indicate that it is not available. It is used, if provided,
1722 * as a fast check on the profile when checking to see if it is sRGB.
1723 */
1724#endif
1725#endif /* iCCP */
1726
1727#ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1728PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
1729 (png_structrp png_ptr), PNG_EMPTY);
1730 /* Set the rgb_to_gray coefficients from the colorspace Y values */
1731#endif /* READ_RGB_TO_GRAY */
1732#endif /* COLORSPACE */
1733
1734/* Added at libpng version 1.4.0 */
1735PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
1736 png_uint_32 width, png_uint_32 height, int bit_depth,
1737 int color_type, int interlace_type, int compression_type,
1738 int filter_type),PNG_EMPTY);
1739
1740/* Added at libpng version 1.5.10 */
1741#if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
1742 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
1743PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
1744 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
1745#endif
1746
1747#if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1748PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
1749 png_const_charp name),PNG_NORETURN);
1750#endif
1751
1752/* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1753 * the end. Always leaves the buffer nul terminated. Never errors out (and
1754 * there is no error code.)
1755 */
1756PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
1757 size_t pos, png_const_charp string),PNG_EMPTY);
1758
1759/* Various internal functions to handle formatted warning messages, currently
1760 * only implemented for warnings.
1761 */
1762#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1763/* Utility to dump an unsigned value into a buffer, given a start pointer and
1764 * and end pointer (which should point just *beyond* the end of the buffer!)
1765 * Returns the pointer to the start of the formatted string. This utility only
1766 * does unsigned values.
1767 */
1768PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
1769 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
1770
1771/* Convenience macro that takes an array: */
1772#define PNG_FORMAT_NUMBER(buffer,format,number) \
1773 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1774
1775/* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1776#define PNG_NUMBER_BUFFER_SIZE 24
1777
1778/* These are the integer formats currently supported, the name is formed from
1779 * the standard printf(3) format string.
1780 */
1781#define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1782#define PNG_NUMBER_FORMAT_02u 2
1783#define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1784#define PNG_NUMBER_FORMAT_02d 2
1785#define PNG_NUMBER_FORMAT_x 3
1786#define PNG_NUMBER_FORMAT_02x 4
1787#define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1788#endif
1789
1790#ifdef PNG_WARNINGS_SUPPORTED
1791/* New defines and members adding in libpng-1.5.4 */
1792# define PNG_WARNING_PARAMETER_SIZE 32
1793# define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
1794
1795/* An l-value of this type has to be passed to the APIs below to cache the
1796 * values of the parameters to a formatted warning message.
1797 */
1798typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1799 PNG_WARNING_PARAMETER_SIZE];
1800
1801PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
1802 int number, png_const_charp string),PNG_EMPTY);
1803 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1804 * including the trailing '\0'.
1805 */
1806PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
1807 (png_warning_parameters p, int number, int format, png_alloc_size_t value),
1808 PNG_EMPTY);
1809 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1810 * need to output. Use the following for a signed value.
1811 */
1812PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
1813 (png_warning_parameters p, int number, int format, png_int_32 value),
1814 PNG_EMPTY);
1815
1816PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
1817 png_warning_parameters p, png_const_charp message),PNG_EMPTY);
1818 /* 'message' follows the X/Open approach of using @1, @2 to insert
1819 * parameters previously supplied using the above functions. Errors in
1820 * specifying the parameters will simply result in garbage substitutions.
1821 */
1822#endif
1823
1824#ifdef PNG_BENIGN_ERRORS_SUPPORTED
1825/* Application errors (new in 1.6); use these functions (declared below) for
1826 * errors in the parameters or order of API function calls on read. The
1827 * 'warning' should be used for an error that can be handled completely; the
1828 * 'error' for one which can be handled safely but which may lose application
1829 * information or settings.
1830 *
1831 * By default these both result in a png_error call prior to release, while in a
1832 * released version the 'warning' is just a warning. However if the application
1833 * explicitly disables benign errors (explicitly permitting the code to lose
1834 * information) they both turn into warnings.
1835 *
1836 * If benign errors aren't supported they end up as the corresponding base call
1837 * (png_warning or png_error.)
1838 */
1839PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
1840 png_const_charp message),PNG_EMPTY);
1841 /* The application provided invalid parameters to an API function or called
1842 * an API function at the wrong time, libpng can completely recover.
1843 */
1844
1845PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
1846 png_const_charp message),PNG_EMPTY);
1847 /* As above but libpng will ignore the call, or attempt some other partial
1848 * recovery from the error.
1849 */
1850#else
1851# define png_app_warning(pp,s) png_warning(pp,s)
1852# define png_app_error(pp,s) png_error(pp,s)
1853#endif
1854
1855PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
1856 png_const_charp message, int error),PNG_EMPTY);
1857 /* Report a recoverable issue in chunk data. On read this is used to report
1858 * a problem found while reading a particular chunk and the
1859 * png_chunk_benign_error or png_chunk_warning function is used as
1860 * appropriate. On write this is used to report an error that comes from
1861 * data set via an application call to a png_set_ API and png_app_error or
1862 * png_app_warning is used as appropriate.
1863 *
1864 * The 'error' parameter must have one of the following values:
1865 */
1866#define PNG_CHUNK_WARNING 0 /* never an error */
1867#define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
1868#define PNG_CHUNK_ERROR 2 /* always an error */
1869
1870/* ASCII to FP interfaces, currently only implemented if sCAL
1871 * support is required.
1872 */
1873#if defined(PNG_sCAL_SUPPORTED)
1874/* MAX_DIGITS is actually the maximum number of characters in an sCAL
1875 * width or height, derived from the precision (number of significant
1876 * digits - a build time settable option) and assumptions about the
1877 * maximum ridiculous exponent.
1878 */
1879#define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1880
1881#ifdef PNG_FLOATING_POINT_SUPPORTED
1882PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
1883 png_charp ascii, size_t size, double fp, unsigned int precision),
1884 PNG_EMPTY);
1885#endif /* FLOATING_POINT */
1886
1887#ifdef PNG_FIXED_POINT_SUPPORTED
1888PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
1889 png_charp ascii, size_t size, png_fixed_point fp),PNG_EMPTY);
1890#endif /* FIXED_POINT */
1891#endif /* sCAL */
1892
1893#if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1894/* An internal API to validate the format of a floating point number.
1895 * The result is the index of the next character. If the number is
1896 * not valid it will be the index of a character in the supposed number.
1897 *
1898 * The format of a number is defined in the PNG extensions specification
1899 * and this API is strictly conformant to that spec, not anyone elses!
1900 *
1901 * The format as a regular expression is:
1902 *
1903 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1904 *
1905 * or:
1906 *
1907 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1908 *
1909 * The complexity is that either integer or fraction must be present and the
1910 * fraction is permitted to have no digits only if the integer is present.
1911 *
1912 * NOTE: The dangling E problem.
1913 * There is a PNG valid floating point number in the following:
1914 *
1915 * PNG floating point numbers are not greedy.
1916 *
1917 * Working this out requires *TWO* character lookahead (because of the
1918 * sign), the parser does not do this - it will fail at the 'r' - this
1919 * doesn't matter for PNG sCAL chunk values, but it requires more care
1920 * if the value were ever to be embedded in something more complex. Use
1921 * ANSI-C strtod if you need the lookahead.
1922 */
1923/* State table for the parser. */
1924#define PNG_FP_INTEGER 0 /* before or in integer */
1925#define PNG_FP_FRACTION 1 /* before or in fraction */
1926#define PNG_FP_EXPONENT 2 /* before or in exponent */
1927#define PNG_FP_STATE 3 /* mask for the above */
1928#define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1929#define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1930#define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1931#define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1932#define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1933
1934/* These three values don't affect the parser. They are set but not used.
1935 */
1936#define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1937#define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1938#define PNG_FP_NONZERO 256 /* A non-zero value */
1939#define PNG_FP_STICKY 448 /* The above three flags */
1940
1941/* This is available for the caller to store in 'state' if required. Do not
1942 * call the parser after setting it (the parser sometimes clears it.)
1943 */
1944#define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1945
1946/* Result codes for the parser (boolean - true meants ok, false means
1947 * not ok yet.)
1948 */
1949#define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1950#define PNG_FP_OK 1 /* The number is valid */
1951
1952/* Tests on the sticky non-zero and negative flags. To pass these checks
1953 * the state must also indicate that the whole number is valid - this is
1954 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1955 * is equivalent to PNG_FP_OK above.)
1956 */
1957#define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1958 /* NZ_MASK: the string is valid and a non-zero negative value */
1959#define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
1960 /* Z MASK: the string is valid and a non-zero value. */
1961 /* PNG_FP_SAW_DIGIT: the string is valid. */
1962#define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
1963#define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
1964#define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
1965
1966/* The actual parser. This can be called repeatedly. It updates
1967 * the index into the string and the state variable (which must
1968 * be initialized to 0). It returns a result code, as above. There
1969 * is no point calling the parser any more if it fails to advance to
1970 * the end of the string - it is stuck on an invalid character (or
1971 * terminated by '\0').
1972 *
1973 * Note that the pointer will consume an E or even an E+ and then leave
1974 * a 'maybe' state even though a preceding integer.fraction is valid.
1975 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
1976 * a valid number. It's possible to recover from this by calling
1977 * the parser again (from the start, with state 0) but with a string
1978 * that omits the last character (i.e. set the size to the index of
1979 * the problem character.) This has not been tested within libpng.
1980 */
1981PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
1982 size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
1983
1984/* This is the same but it checks a complete string and returns true
1985 * only if it just contains a floating point number. As of 1.5.4 this
1986 * function also returns the state at the end of parsing the number if
1987 * it was valid (otherwise it returns 0.) This can be used for testing
1988 * for negative or zero values using the sticky flag.
1989 */
1990PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
1991 size_t size),PNG_EMPTY);
1992#endif /* pCAL || sCAL */
1993
1994#if defined(PNG_GAMMA_SUPPORTED) ||\
1995 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
1996/* Added at libpng version 1.5.0 */
1997/* This is a utility to provide a*times/div (rounded) and indicate
1998 * if there is an overflow. The result is a boolean - false (0)
1999 * for overflow, true (1) if no overflow, in which case *res
2000 * holds the result.
2001 */
2002PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
2003 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
2004#endif
2005
2006#if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
2007/* Same deal, but issue a warning on overflow and return 0. */
2008PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
2009 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
2010 png_int_32 divided_by),PNG_EMPTY);
2011#endif
2012
2013#ifdef PNG_GAMMA_SUPPORTED
2014/* Calculate a reciprocal - used for gamma values. This returns
2015 * 0 if the argument is 0 in order to maintain an undefined value;
2016 * there are no warnings.
2017 */
2018PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
2019 PNG_EMPTY);
2020
2021#ifdef PNG_READ_GAMMA_SUPPORTED
2022/* The same but gives a reciprocal of the product of two fixed point
2023 * values. Accuracy is suitable for gamma calculations but this is
2024 * not exact - use png_muldiv for that. Only required at present on read.
2025 */
2026PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
2027 png_fixed_point b),PNG_EMPTY);
2028#endif
2029
2030/* Return true if the gamma value is significantly different from 1.0 */
2031PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
2032 PNG_EMPTY);
2033#endif
2034
2035#ifdef PNG_READ_GAMMA_SUPPORTED
2036/* Internal fixed point gamma correction. These APIs are called as
2037 * required to convert single values - they don't need to be fast,
2038 * they are not used when processing image pixel values.
2039 *
2040 * While the input is an 'unsigned' value it must actually be the
2041 * correct bit value - 0..255 or 0..65535 as required.
2042 */
2043PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
2044 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
2045PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
2046 png_fixed_point gamma_value),PNG_EMPTY);
2047PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
2048 png_fixed_point gamma_value),PNG_EMPTY);
2049PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
2050 PNG_EMPTY);
2051PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
2052 int bit_depth),PNG_EMPTY);
2053#endif
2054
2055/* SIMPLIFIED READ/WRITE SUPPORT */
2056#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
2057 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
2058/* The internal structure that png_image::opaque points to. */
2059typedef struct png_control
2060{
2061 png_structp png_ptr;
2062 png_infop info_ptr;
2063 png_voidp error_buf; /* Always a jmp_buf at present. */
2064
2065 png_const_bytep memory; /* Memory buffer. */
2066 size_t size; /* Size of the memory buffer. */
2067
2068 unsigned int for_write :1; /* Otherwise it is a read structure */
2069 unsigned int owned_file :1; /* We own the file in io_ptr */
2070} png_control;
2071
2072/* Return the pointer to the jmp_buf from a png_control: necessary because C
2073 * does not reveal the type of the elements of jmp_buf.
2074 */
2075#ifdef __cplusplus
2076# define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
2077#else
2078# define png_control_jmp_buf(pc) ((pc)->error_buf)
2079#endif
2080
2081/* Utility to safely execute a piece of libpng code catching and logging any
2082 * errors that might occur. Returns true on success, false on failure (either
2083 * of the function or as a result of a png_error.)
2084 */
2085PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr,
2086 png_const_charp error_message),PNG_NORETURN);
2087
2088#ifdef PNG_WARNINGS_SUPPORTED
2089PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr,
2090 png_const_charp warning_message),PNG_EMPTY);
2091#else
2092# define png_safe_warning 0/*dummy argument*/
2093#endif
2094
2095PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
2096 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
2097
2098/* Utility to log an error; this also cleans up the png_image; the function
2099 * always returns 0 (false).
2100 */
2101PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
2102 png_const_charp error_message),PNG_EMPTY);
2103
2104#ifndef PNG_SIMPLIFIED_READ_SUPPORTED
2105/* png_image_free is used by the write code but not exported */
2106PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
2107#endif /* !SIMPLIFIED_READ */
2108
2109#endif /* SIMPLIFIED READ/WRITE */
2110
2111/* These are initialization functions for hardware specific PNG filter
2112 * optimizations; list these here then select the appropriate one at compile
2113 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
2114 * the generic code is used.
2115 */
2116#ifdef PNG_FILTER_OPTIMIZATIONS
2117PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
2118 unsigned int bpp), PNG_EMPTY);
2119 /* Just declare the optimization that will be used */
2120#else
2121 /* List *all* the possible optimizations here - this branch is required if
2122 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
2123 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
2124 */
2125# if PNG_ARM_NEON_OPT > 0
2126PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
2127 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2128#endif
2129
2130#if PNG_MIPS_MSA_OPT > 0
2131PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_msa,
2132 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2133#endif
2134
2135# if PNG_INTEL_SSE_IMPLEMENTATION > 0
2136PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_sse2,
2137 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
2138# endif
2139#endif
2140
2141PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
2142 png_const_charp key, png_bytep new_key), PNG_EMPTY);
2143
2144/* Maintainer: Put new private prototypes here ^ */
2145
2146#include "pngdebug.h"
2147
2148#ifdef __cplusplus
2149}
2150#endif
2151
2152#endif /* PNG_VERSION_INFO_ONLY */
2153#endif /* PNGPRIV_H */
2154