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 1.6.22 [May 26, 2016]
33 * Copyright (c) 1998-2002,2004,2006-2016 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 #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
67
68 #ifndef PNG_VERSION_INFO_ONLY
69 /* Standard library headers not required by png.h: */
70 # include <stdlib.h>
71 # include <string.h>
72 #endif
73
74 #define PNGLIB_BUILD /*libpng is being built, not used*/
75
76 /* If HAVE_CONFIG_H is defined during the build then the build system must
77 * provide an appropriate "config.h" file on the include path. The header file
78 * must provide definitions as required below (search for "HAVE_CONFIG_H");
79 * see configure.ac for more details of the requirements. The macro
80 * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on
81 * 'configure'; define this macro to prevent the configure build including the
82 * configure generated config.h. Libpng is expected to compile without *any*
83 * special build system support on a reasonably ANSI-C compliant system.
84 */
85 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
86 # include <config.h>
87
88 /* Pick up the definition of 'restrict' from config.h if it was read: */
89 # define PNG_RESTRICT restrict
90 #endif
91
92 /* To support symbol prefixing it is necessary to know *before* including png.h
93 * whether the fixed point (and maybe other) APIs are exported, because if they
94 * are not internal definitions may be required. This is handled below just
95 * before png.h is included, but load the configuration now if it is available.
96 */
97 #ifndef PNGLCONF_H
98 # include "pnglibconf.h"
99 #endif
100
101 /* Local renames may change non-exported API functions from png.h */
102 #if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
103 # include "pngprefix.h"
104 #endif
105
106 #ifdef PNG_USER_CONFIG
107 # include "pngusr.h"
108 /* These should have been defined in pngusr.h */
109 # ifndef PNG_USER_PRIVATEBUILD
110 # define PNG_USER_PRIVATEBUILD "Custom libpng build"
111 # endif
112 # ifndef PNG_USER_DLLFNAME_POSTFIX
113 # define PNG_USER_DLLFNAME_POSTFIX "Cb"
114 # endif
115 #endif
116
117 /* Compile time options.
118 * =====================
119 * In a multi-arch build the compiler may compile the code several times for the
120 * same object module, producing different binaries for different architectures.
121 * When this happens configure-time setting of the target host options cannot be
122 * done and this interferes with the handling of the ARM NEON optimizations, and
123 * possibly other similar optimizations. Put additional tests here; in general
124 * this is needed when the same option can be changed at both compile time and
125 * run time depending on the target OS (i.e. iOS vs Android.)
126 *
127 * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
128 * this is not possible with certain compilers (Oracle SUN OS CC), as a result
129 * it is necessary to ensure that all extern functions that *might* be used
130 * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__
131 * below is one example of this behavior because it is controlled by the
132 * presence or not of -mfpu=neon on the GCC command line, it is possible to do
133 * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
134 * do this.
135 */
136 #ifndef PNG_ARM_NEON_OPT
137 /* ARM NEON optimizations are being controlled by the compiler settings,
138 * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon
139 * with GCC) then the compiler will define __ARM_NEON__ and we can rely
140 * unconditionally on NEON instructions not crashing, otherwise we must
141 * disable use of NEON instructions.
142 *
143 * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
144 * can only be turned on automatically if that is supported too. If
145 * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
146 * to compile with an appropriate #error if ALIGNED_MEMORY has been turned
147 * off.
148 *
149 * Note that gcc-4.9 defines __ARM_NEON instead of the deprecated
150 * __ARM_NEON__, so we check both variants.
151 *
152 * To disable ARM_NEON optimizations entirely, and skip compiling the
153 * associated assembler code, pass --enable-arm-neon=no to configure
154 * or put -DPNG_ARM_NEON_OPT=0 in CPPFLAGS.
155 */
156 # if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \
157 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
158 # define PNG_ARM_NEON_OPT 2
159 # else
160 # define PNG_ARM_NEON_OPT 0
161 # endif
162 #endif
163
164 #if PNG_ARM_NEON_OPT > 0
165 /* NEON optimizations are to be at least considered by libpng, so enable the
166 * callbacks to do this.
167 */
168 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
169
170 /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used
171 * if possible - if __ARM_NEON__ is set and the compiler version is not known
172 * to be broken. This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can
173 * be:
174 *
175 * 1 The intrinsics code (the default with __ARM_NEON__)
176 * 2 The hand coded assembler (the default without __ARM_NEON__)
177 *
178 * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however
179 * this is *NOT* supported and may cease to work even after a minor revision
180 * to libpng. It *is* valid to do this for testing purposes, e.g. speed
181 * testing or a new compiler, but the results should be communicated to the
182 * libpng implementation list for incorporation in the next minor release.
183 */
184 # ifndef PNG_ARM_NEON_IMPLEMENTATION
185 # if defined(__ARM_NEON__) || defined(__ARM_NEON)
186 # if defined(__clang__)
187 /* At present it is unknown by the libpng developers which versions
188 * of clang support the intrinsics, however some or perhaps all
189 * versions do not work with the assembler so this may be
190 * irrelevant, so just use the default (do nothing here.)
191 */
192 # elif defined(__GNUC__)
193 /* GCC 4.5.4 NEON support is known to be broken. 4.6.3 is known to
194 * work, so if this *is* GCC, or G++, look for a version >4.5
195 */
196 # if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)
197 # define PNG_ARM_NEON_IMPLEMENTATION 2
198 # endif /* no GNUC support */
199 # endif /* __GNUC__ */
200 # else /* !defined __ARM_NEON__ */
201 /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
202 */
203 # define PNG_ARM_NEON_IMPLEMENTATION 2
204 # endif /* __ARM_NEON__ */
205 # endif /* !PNG_ARM_NEON_IMPLEMENTATION */
206
207 # ifndef PNG_ARM_NEON_IMPLEMENTATION
208 /* Use the intrinsics code by default. */
209 # define PNG_ARM_NEON_IMPLEMENTATION 1
210 # endif
211 #endif /* PNG_ARM_NEON_OPT > 0 */
212
213 /* Is this a build of a DLL where compilation of the object modules requires
214 * different preprocessor settings to those required for a simple library? If
215 * so PNG_BUILD_DLL must be set.
216 *
217 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
218 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
219 * static library of libpng then link the DLL against that.
220 */
221 #ifndef PNG_BUILD_DLL
222 # ifdef DLL_EXPORT
223 /* This is set by libtool when files are compiled for a DLL; libtool
224 * always compiles twice, even on systems where it isn't necessary. Set
225 * PNG_BUILD_DLL in case it is necessary:
226 */
227 # define PNG_BUILD_DLL
228 # else
229 # ifdef _WINDLL
230 /* This is set by the Microsoft Visual Studio IDE in projects that
231 * build a DLL. It can't easily be removed from those projects (it
232 * isn't visible in the Visual Studio UI) so it is a fairly reliable
233 * indication that PNG_IMPEXP needs to be set to the DLL export
234 * attributes.
235 */
236 # define PNG_BUILD_DLL
237 # else
238 # ifdef __DLL__
239 /* This is set by the Borland C system when compiling for a DLL
240 * (as above.)
241 */
242 # define PNG_BUILD_DLL
243 # else
244 /* Add additional compiler cases here. */
245 # endif
246 # endif
247 # endif
248 #endif /* Setting PNG_BUILD_DLL if required */
249
250 /* See pngconf.h for more details: the builder of the library may set this on
251 * the command line to the right thing for the specific compilation system or it
252 * may be automagically set above (at present we know of no system where it does
253 * need to be set on the command line.)
254 *
255 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
256 * setting it to the "import" setting for a DLL build.
257 */
258 #ifndef PNG_IMPEXP
259 # ifdef PNG_BUILD_DLL
260 # define PNG_IMPEXP PNG_DLL_EXPORT
261 # else
262 /* Not building a DLL, or the DLL doesn't require specific export
263 * definitions.
264 */
265 # define PNG_IMPEXP
266 # endif
267 #endif
268
269 /* No warnings for private or deprecated functions in the build: */
270 #ifndef PNG_DEPRECATED
271 # define PNG_DEPRECATED
272 #endif
273 #ifndef PNG_PRIVATE
274 # define PNG_PRIVATE
275 #endif
276
277 /* Symbol preprocessing support.
278 *
279 * To enable listing global, but internal, symbols the following macros should
280 * always be used to declare an extern data or function object in this file.
281 */
282 #ifndef PNG_INTERNAL_DATA
283 # define PNG_INTERNAL_DATA(type, name, array) PNG_LINKAGE_DATA type name array
284 #endif
285
286 #ifndef PNG_INTERNAL_FUNCTION
287 # define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
288 PNG_LINKAGE_FUNCTION PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
289 #endif
290
291 #ifndef PNG_INTERNAL_CALLBACK
292 # define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
293 PNG_LINKAGE_CALLBACK PNG_FUNCTION(type, (PNGCBAPI name), args,\
294 PNG_EMPTY attributes)
295 #endif
296
297 /* If floating or fixed point APIs are disabled they may still be compiled
298 * internally. To handle this make sure they are declared as the appropriate
299 * internal extern function (otherwise the symbol prefixing stuff won't work and
300 * the functions will be used without definitions.)
301 *
302 * NOTE: although all the API functions are declared here they are not all
303 * actually built! Because the declarations are still made it is necessary to
304 * fake out types that they depend on.
305 */
306 #ifndef PNG_FP_EXPORT
307 # ifndef PNG_FLOATING_POINT_SUPPORTED
308 # define PNG_FP_EXPORT(ordinal, type, name, args)\
309 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
310 # ifndef PNG_VERSION_INFO_ONLY
311 typedef struct png_incomplete png_double;
312 typedef png_double* png_doublep;
313 typedef const png_double* png_const_doublep;
314 typedef png_double** png_doublepp;
315 # endif
316 # endif
317 #endif
318 #ifndef PNG_FIXED_EXPORT
319 # ifndef PNG_FIXED_POINT_SUPPORTED
320 # define PNG_FIXED_EXPORT(ordinal, type, name, args)\
321 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
322 # endif
323 #endif
324
325 #include "png.h"
326
327 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
328 #ifndef PNG_DLL_EXPORT
329 # define PNG_DLL_EXPORT
330 #endif
331
332 /* This is a global switch to set the compilation for an installed system
333 * (a release build). It can be set for testing debug builds to ensure that
334 * they will compile when the build type is switched to RC or STABLE, the
335 * default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS
336 * with either:
337 *
338 * -DPNG_RELEASE_BUILD Turns on the release compile path
339 * -DPNG_RELEASE_BUILD=0 Turns it off
340 * or in your pngusr.h with
341 * #define PNG_RELEASE_BUILD=1 Turns on the release compile path
342 * #define PNG_RELEASE_BUILD=0 Turns it off
343 */
344 #ifndef PNG_RELEASE_BUILD
345 # define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC)
346 #endif
347
348 /* SECURITY and SAFETY:
349 *
350 * libpng is built with support for internal limits on image dimensions and
351 * memory usage. These are documented in scripts/pnglibconf.dfa of the
352 * source and recorded in the machine generated header file pnglibconf.h.
353 */
354
355 /* If you are running on a machine where you cannot allocate more
356 * than 64K of memory at once, uncomment this. While libpng will not
357 * normally need that much memory in a chunk (unless you load up a very
358 * large file), zlib needs to know how big of a chunk it can use, and
359 * libpng thus makes sure to check any memory allocation to verify it
360 * will fit into memory.
361 *
362 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
363 * same limit and pngconf.h (already included) sets the limit
364 * if certain operating systems are detected.
365 */
366 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
367 # define PNG_MAX_MALLOC_64K
368 #endif
369
370 #ifndef PNG_UNUSED
371 /* Unused formal parameter warnings are silenced using the following macro
372 * which is expected to have no bad effects on performance (optimizing
373 * compilers will probably remove it entirely). Note that if you replace
374 * it with something other than whitespace, you must include the terminating
375 * semicolon.
376 */
377 # define PNG_UNUSED(param) (void)param;
378 #endif
379
380 /* Just a little check that someone hasn't tried to define something
381 * contradictory.
382 */
383 #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
384 # undef PNG_ZBUF_SIZE
385 # define PNG_ZBUF_SIZE 65536L
386 #endif
387
388 /* If warnings or errors are turned off the code is disabled or redirected here.
389 * From 1.5.4 functions have been added to allow very limited formatting of
390 * error and warning messages - this code will also be disabled here.
391 */
392 #ifdef PNG_WARNINGS_SUPPORTED
393 # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
394 #else
395 # define png_warning_parameter(p,number,string) ((void)0)
396 # define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
397 # define png_warning_parameter_signed(p,number,format,value) ((void)0)
398 # define png_formatted_warning(pp,p,message) ((void)(pp))
399 # define PNG_WARNING_PARAMETERS(p)
400 #endif
401 #ifndef PNG_ERROR_TEXT_SUPPORTED
402 # define png_fixed_error(s1,s2) png_err(s1)
403 #endif
404
405 /* C allows up-casts from (void*) to any pointer and (const void*) to any
406 * pointer to a const object. C++ regards this as a type error and requires an
407 * explicit, static, cast and provides the static_cast<> rune to ensure that
408 * const is not cast away.
409 */
410 #ifdef __cplusplus
411 # define png_voidcast(type, value) static_cast<type>(value)
412 # define png_constcast(type, value) const_cast<type>(value)
413 # define png_aligncast(type, value) \
414 static_cast<type>(static_cast<void*>(value))
415 # define png_aligncastconst(type, value) \
416 static_cast<type>(static_cast<const void*>(value))
417 #else
418 # define png_voidcast(type, value) (value)
419 # define png_constcast(type, value) ((type)(value))
420 # define png_aligncast(type, value) ((void*)(value))
421 # define png_aligncastconst(type, value) ((const void*)(value))
422 #endif /* __cplusplus */
423
424 /* Some fixed point APIs are still required even if not exported because
425 * they get used by the corresponding floating point APIs. This magic
426 * deals with this:
427 */
428 #ifdef PNG_FIXED_POINT_SUPPORTED
429 # define PNGFAPI PNGAPI
430 #else
431 # define PNGFAPI /* PRIVATE */
432 #endif
433
434 #ifndef PNG_VERSION_INFO_ONLY
435 /* Other defines specific to compilers can go here. Try to keep
436 * them inside an appropriate ifdef/endif pair for portability.
437 */
438 #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
439 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
440 /* png.c requires the following ANSI-C constants if the conversion of
441 * floating point to ASCII is implemented therein:
442 *
443 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
444 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
445 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
446 */
447 # include <float.h>
448
449 # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
450 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
451 /* We need to check that <math.h> hasn't already been included earlier
452 * as it seems it doesn't agree with <fp.h>, yet we should really use
453 * <fp.h> if possible.
454 */
455 # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
456 # include <fp.h>
457 # endif
458 # else
459 # include <math.h>
460 # endif
461 # if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
462 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
463 * MATH=68881
464 */
465 # include <m68881.h>
466 # endif
467 #endif
468
469 /* This provides the non-ANSI (far) memory allocation routines. */
470 #if defined(__TURBOC__) && defined(__MSDOS__)
471 # include <mem.h>
472 # include <alloc.h>
473 #endif
474
475 #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
476 defined(_WIN32) || defined(__WIN32__)
477 # include <windows.h> /* defines _WINDOWS_ macro */
478 #endif
479 #endif /* PNG_VERSION_INFO_ONLY */
480
481 /* Moved here around 1.5.0beta36 from pngconf.h */
482 /* Users may want to use these so they are not private. Any library
483 * functions that are passed far data must be model-independent.
484 */
485
486 /* Memory model/platform independent fns */
487 #ifndef PNG_ABORT
488 # ifdef _WINDOWS_
489 # define PNG_ABORT() ExitProcess(0)
490 # else
491 # define PNG_ABORT() abort()
492 # endif
493 #endif
494
495 /* These macros may need to be architecture dependent. */
496 #define PNG_ALIGN_NONE 0 /* do not use data alignment */
497 #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
498 #ifdef offsetof
499 # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
500 #else
501 # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
502 #endif
503 #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
504
505 #ifndef PNG_ALIGN_TYPE
506 /* Default to using aligned access optimizations and requiring alignment to a
507 * multiple of the data type size. Override in a compiler specific fashion
508 * if necessary by inserting tests here:
509 */
510 # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
511 #endif
512
513 #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
514 /* This is used because in some compiler implementations non-aligned
515 * structure members are supported, so the offsetof approach below fails.
516 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
517 * is good for performance. Do not do this unless you have tested the result
518 * and understand it.
519 */
520 # define png_alignof(type) (sizeof (type))
521 #else
522 # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
523 # define png_alignof(type) offsetof(struct{char c; type t;}, t)
524 # else
525 # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
526 # define png_alignof(type) (1)
527 # endif
528 /* Else leave png_alignof undefined to prevent use thereof */
529 # endif
530 #endif
531
532 /* This implicitly assumes alignment is always to a power of 2. */
533 #ifdef png_alignof
534 # define png_isaligned(ptr, type)\
535 ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
536 #else
537 # define png_isaligned(ptr, type) 0
538 #endif
539
540 /* End of memory model/platform independent support */
541 /* End of 1.5.0beta36 move from pngconf.h */
542
543 /* CONSTANTS and UTILITY MACROS
544 * These are used internally by libpng and not exposed in the API
545 */
546
547 /* Various modes of operation. Note that after an init, mode is set to
548 * zero automatically when the structure is created. Three of these
549 * are defined in png.h because they need to be visible to applications
550 * that call png_set_unknown_chunk().
551 */
552 /* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
553 /* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
554 #define PNG_HAVE_IDAT 0x04
555 /* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
556 #define PNG_HAVE_IEND 0x10
557 /* 0x20 (unused) */
558 /* 0x40 (unused) */
559 /* 0x80 (unused) */
560 #define PNG_HAVE_CHUNK_HEADER 0x100
561 #define PNG_WROTE_tIME 0x200
562 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
563 #define PNG_BACKGROUND_IS_GRAY 0x800
564 #define PNG_HAVE_PNG_SIGNATURE 0x1000
565 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
566 /* 0x4000 (unused) */
567 #define PNG_IS_READ_STRUCT 0x8000 /* Else is a write struct */
568
569 /* Flags for the transformations the PNG library does on the image data */
570 #define PNG_BGR 0x0001
571 #define PNG_INTERLACE 0x0002
572 #define PNG_PACK 0x0004
573 #define PNG_SHIFT 0x0008
574 #define PNG_SWAP_BYTES 0x0010
575 #define PNG_INVERT_MONO 0x0020
576 #define PNG_QUANTIZE 0x0040
577 #define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
578 #define PNG_BACKGROUND_EXPAND 0x0100
579 #define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
580 #define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
581 #define PNG_RGBA 0x0800
582 #define PNG_EXPAND 0x1000
583 #define PNG_GAMMA 0x2000
584 #define PNG_GRAY_TO_RGB 0x4000
585 #define PNG_FILLER 0x8000
586 #define PNG_PACKSWAP 0x10000
587 #define PNG_SWAP_ALPHA 0x20000
588 #define PNG_STRIP_ALPHA 0x40000
589 #define PNG_INVERT_ALPHA 0x80000
590 #define PNG_USER_TRANSFORM 0x100000
591 #define PNG_RGB_TO_GRAY_ERR 0x200000
592 #define PNG_RGB_TO_GRAY_WARN 0x400000
593 #define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
594 #define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
595 #define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
596 #define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
597 #define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
598 /* 0x8000000 unused */
599 /* 0x10000000 unused */
600 /* 0x20000000 unused */
601 /* 0x40000000 unused */
602 /* Flags for png_create_struct */
603 #define PNG_STRUCT_PNG 0x0001
604 #define PNG_STRUCT_INFO 0x0002
605
606 /* Flags for the png_ptr->flags rather than declaring a byte for each one */
607 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
608 #define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002 /* Added to libpng-1.6.0 */
609 /* 0x0004 unused */
610 #define PNG_FLAG_ZSTREAM_ENDED 0x0008 /* Added to libpng-1.6.0 */
611 /* 0x0010 unused */
612 /* 0x0020 unused */
613 #define PNG_FLAG_ROW_INIT 0x0040
614 #define PNG_FLAG_FILLER_AFTER 0x0080
615 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
616 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
617 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
618 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
619 #define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
620 #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
621 #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
622 /* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000 */
623 /* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000 */
624 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000
625 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
626 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
627 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000 /* Added to libpng-1.4.0 */
628 #define PNG_FLAG_APP_WARNINGS_WARN 0x200000 /* Added to libpng-1.6.0 */
629 #define PNG_FLAG_APP_ERRORS_WARN 0x400000 /* Added to libpng-1.6.0 */
630 /* 0x800000 unused */
631 /* 0x1000000 unused */
632 /* 0x2000000 unused */
633 /* 0x4000000 unused */
634 /* 0x8000000 unused */
635 /* 0x10000000 unused */
636 /* 0x20000000 unused */
637 /* 0x40000000 unused */
638
639 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
640 PNG_FLAG_CRC_ANCILLARY_NOWARN)
641
642 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
643 PNG_FLAG_CRC_CRITICAL_IGNORE)
644
645 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
646 PNG_FLAG_CRC_CRITICAL_MASK)
647
648 /* Save typing and make code easier to understand */
649
650 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
651 abs((int)((c1).green) - (int)((c2).green)) + \
652 abs((int)((c1).blue) - (int)((c2).blue)))
653
654 /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
655 * by dividing by 257 *with rounding*. This macro is exact for the given range.
656 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the
657 * macro were established by experiment (modifying the added value). The macro
658 * has a second variant that takes a value already scaled by 255 and divides by
659 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it
660 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
661 */
662 #define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
663 #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
664
665 /* Added to libpng-1.2.6 JB */
666 #define PNG_ROWBYTES(pixel_bits, width) \
667 ((pixel_bits) >= 8 ? \
668 ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
669 (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
670
671 /* PNG_OUT_OF_RANGE returns true if value is outside the range
672 * ideal-delta..ideal+delta. Each argument is evaluated twice.
673 * "ideal" and "delta" should be constants, normally simple
674 * integers, "value" a variable. Added to libpng-1.2.6 JB
675 */
676 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
677 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
678
679 /* Conversions between fixed and floating point, only defined if
680 * required (to make sure the code doesn't accidentally use float
681 * when it is supposedly disabled.)
682 */
683 #ifdef PNG_FLOATING_POINT_SUPPORTED
684 /* The floating point conversion can't overflow, though it can and
685 * does lose accuracy relative to the original fixed point value.
686 * In practice this doesn't matter because png_fixed_point only
687 * stores numbers with very low precision. The png_ptr and s
688 * arguments are unused by default but are there in case error
689 * checking becomes a requirement.
690 */
691 #define png_float(png_ptr, fixed, s) (.00001 * (fixed))
692
693 /* The fixed point conversion performs range checking and evaluates
694 * its argument multiple times, so must be used with care. The
695 * range checking uses the PNG specification values for a signed
696 * 32-bit fixed point value except that the values are deliberately
697 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
698 * (2^31-1) * 100000). 's' is a string that describes the value being
699 * converted.
700 *
701 * NOTE: this macro will raise a png_error if the range check fails,
702 * therefore it is normally only appropriate to use this on values
703 * that come from API calls or other sources where an out of range
704 * error indicates a programming error, not a data error!
705 *
706 * NOTE: by default this is off - the macro is not used - because the
707 * function call saves a lot of code.
708 */
709 #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
710 #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
711 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
712 #endif
713 /* else the corresponding function is defined below, inside the scope of the
714 * cplusplus test.
715 */
716 #endif
717
718 /* Constants for known chunk types. If you need to add a chunk, define the name
719 * here. For historical reasons these constants have the form png_<name>; i.e.
720 * the prefix is lower case. Please use decimal values as the parameters to
721 * match the ISO PNG specification and to avoid relying on the C locale
722 * interpretation of character values.
723 *
724 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
725 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
726 * to be generated if required.
727 *
728 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
729 * architectures where (int) is only 16 bits.
730 */
731 #define PNG_32b(b,s) ((png_uint_32)(b) << (s))
732 #define PNG_U32(b1,b2,b3,b4) \
733 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
734
735 /* Constants for known chunk types.
736 *
737 * MAINTAINERS: If you need to add a chunk, define the name here.
738 * For historical reasons these constants have the form png_<name>; i.e.
739 * the prefix is lower case. Please use decimal values as the parameters to
740 * match the ISO PNG specification and to avoid relying on the C locale
741 * interpretation of character values. Please keep the list sorted.
742 *
743 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
744 * type. In fact the specification does not express chunk types this way,
745 * however using a 32-bit value means that the chunk type can be read from the
746 * stream using exactly the same code as used for a 32-bit unsigned value and
747 * can be examined far more efficiently (using one arithmetic compare).
748 *
749 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The
750 * libpng API still uses strings for 'unknown' chunks and a macro,
751 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice
752 * that for portable code numeric values must still be used; the string "IHDR"
753 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
754 *
755 * In 1.7.0 the definitions will be made public in png.h to avoid having to
756 * duplicate the same definitions in application code.
757 */
758 #define png_IDAT PNG_U32( 73, 68, 65, 84)
759 #define png_IEND PNG_U32( 73, 69, 78, 68)
760 #define png_IHDR PNG_U32( 73, 72, 68, 82)
761 #define png_PLTE PNG_U32( 80, 76, 84, 69)
762 #define png_bKGD PNG_U32( 98, 75, 71, 68)
763 #define png_cHRM PNG_U32( 99, 72, 82, 77)
764 #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
765 #define png_gAMA PNG_U32(103, 65, 77, 65)
766 #define png_gIFg PNG_U32(103, 73, 70, 103)
767 #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
768 #define png_gIFx PNG_U32(103, 73, 70, 120)
769 #define png_hIST PNG_U32(104, 73, 83, 84)
770 #define png_iCCP PNG_U32(105, 67, 67, 80)
771 #define png_iTXt PNG_U32(105, 84, 88, 116)
772 #define png_oFFs PNG_U32(111, 70, 70, 115)
773 #define png_pCAL PNG_U32(112, 67, 65, 76)
774 #define png_pHYs PNG_U32(112, 72, 89, 115)
775 #define png_sBIT PNG_U32(115, 66, 73, 84)
776 #define png_sCAL PNG_U32(115, 67, 65, 76)
777 #define png_sPLT PNG_U32(115, 80, 76, 84)
778 #define png_sRGB PNG_U32(115, 82, 71, 66)
779 #define png_sTER PNG_U32(115, 84, 69, 82)
780 #define png_tEXt PNG_U32(116, 69, 88, 116)
781 #define png_tIME PNG_U32(116, 73, 77, 69)
782 #define png_tRNS PNG_U32(116, 82, 78, 83)
783 #define png_zTXt PNG_U32(122, 84, 88, 116)
784
785 /* The following will work on (signed char*) strings, whereas the get_uint_32
786 * macro will fail on top-bit-set values because of the sign extension.
787 */
788 #define PNG_CHUNK_FROM_STRING(s)\
789 PNG_U32(0xff & (s)[0], 0xff & (s)[1], 0xff & (s)[2], 0xff & (s)[3])
790
791 /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
792 * signed and the argument is a (char[]) This macro will fail miserably on
793 * systems where (char) is more than 8 bits.
794 */
795 #define PNG_STRING_FROM_CHUNK(s,c)\
796 (void)(((char*)(s))[0]=(char)(((c)>>24) & 0xff), \
797 ((char*)(s))[1]=(char)(((c)>>16) & 0xff),\
798 ((char*)(s))[2]=(char)(((c)>>8) & 0xff), \
799 ((char*)(s))[3]=(char)((c & 0xff)))
800
801 /* Do the same but terminate with a null character. */
802 #define PNG_CSTRING_FROM_CHUNK(s,c)\
803 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
804
805 /* Test on flag values as defined in the spec (section 5.4): */
806 #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
807 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
808 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
809 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
810 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
811
812 /* Gamma values (new at libpng-1.5.4): */
813 #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
814 #define PNG_GAMMA_MAC_INVERSE 65909
815 #define PNG_GAMMA_sRGB_INVERSE 45455
816
817 /* Almost everything below is C specific; the #defines above can be used in
818 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
819 */
820 #ifndef PNG_VERSION_INFO_ONLY
821
822 #include "pngstruct.h"
823 #include "pnginfo.h"
824
825 /* Validate the include paths - the include path used to generate pnglibconf.h
826 * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
827 */
828 #if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
829 # error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
830 "-I (include path) error: see the notes in pngpriv.h"
831 /* This means that when pnglibconf.h was built the copy of zlib.h that it
832 * used is not the same as the one being used here. Because the build of
833 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
834 * zlib version number and because this affects handling of certain broken
835 * PNG files the -I directives must match.
836 *
837 * The most likely explanation is that you passed a -I in CFLAGS. This will
838 * not work; all the preprocessor directories and in particular all the -I
839 * directives must be in CPPFLAGS.
840 */
841 #endif
842
843 /* This is used for 16-bit gamma tables -- only the top level pointers are
844 * const; this could be changed:
845 */
846 typedef const png_uint_16p * png_const_uint_16pp;
847
848 /* Added to libpng-1.5.7: sRGB conversion tables */
849 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
850 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
851 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED
852 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
853 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
854 * 0..65535. This table gives the closest 16-bit answers (no errors).
855 */
856 #endif
857
858 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
859 PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
860
861 #define PNG_sRGB_FROM_LINEAR(linear) \
862 ((png_byte)(0xff & ((png_sRGB_base[(linear)>>15] \
863 + ((((linear) & 0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8)))
864 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
865 * encoded value with maximum error 0.646365. Note that the input is not a
866 * 16-bit value; it has been multiplied by 255! */
867 #endif /* SIMPLIFIED_READ/WRITE */
868
869
870 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
871 #ifdef __cplusplus
872 extern "C" {
873 #endif /* __cplusplus */
874
875 /* Internal functions; these are not exported from a DLL however because they
876 * are used within several of the C source files they have to be C extern.
877 *
878 * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
879 */
880
881 /* Zlib support */
882 #define PNG_UNEXPECTED_ZLIB_RETURN (-7)
883 PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
884 PNG_EMPTY);
885 /* Used by the zlib handling functions to ensure that z_stream::msg is always
886 * set before they return.
887 */
888
889 #ifdef PNG_WRITE_SUPPORTED
890 PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
891 png_compression_bufferp *list),PNG_EMPTY);
892 /* Free the buffer list used by the compressed write code. */
893 #endif
894
895 #if defined(PNG_FLOATING_POINT_SUPPORTED) && \
896 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
897 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
898 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
899 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
900 (defined(PNG_sCAL_SUPPORTED) && \
901 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
902 PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
903 double fp, png_const_charp text),PNG_EMPTY);
904 #endif
905
906 /* Check the user version string for compatibility, returns false if the version
907 * numbers aren't compatible.
908 */
909 PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
910 png_const_charp user_png_ver),PNG_EMPTY);
911
912 /* Internal base allocator - no messages, NULL on failure to allocate. This
913 * does, however, call the application provided allocator and that could call
914 * png_error (although that would be a bug in the application implementation.)
915 */
916 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
917 png_alloc_size_t size),PNG_ALLOCATED);
918
919 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
920 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
921 /* Internal array allocator, outputs no error or warning messages on failure,
922 * just returns NULL.
923 */
924 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
925 int nelements, size_t element_size),PNG_ALLOCATED);
926
927 /* The same but an existing array is extended by add_elements. This function
928 * also memsets the new elements to 0 and copies the old elements. The old
929 * array is not freed or altered.
930 */
931 PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
932 png_const_voidp array, int old_elements, int add_elements,
933 size_t element_size),PNG_ALLOCATED);
934 #endif /* text, sPLT or unknown chunks */
935
936 /* Magic to create a struct when there is no struct to call the user supplied
937 * memory allocators. Because error handling has not been set up the memory
938 * handlers can't safely call png_error, but this is an obscure and undocumented
939 * restriction so libpng has to assume that the 'free' handler, at least, might
940 * call png_error.
941 */
942 PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
943 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
944 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
945 png_free_ptr free_fn),PNG_ALLOCATED);
946
947 /* Free memory from internal libpng struct */
948 PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
949 PNG_EMPTY);
950
951 /* Free an allocated jmp_buf (always succeeds) */
952 PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
953
954 /* Function to allocate memory for zlib. PNGAPI is disallowed. */
955 PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
956 PNG_ALLOCATED);
957
958 /* Function to free memory for zlib. PNGAPI is disallowed. */
959 PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
960
961 /* Next four functions are used internally as callbacks. PNGCBAPI is required
962 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
963 * PNGCBAPI at 1.5.0
964 */
965
966 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
967 png_bytep data, png_size_t length),PNG_EMPTY);
968
969 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
970 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
971 png_bytep buffer, png_size_t length),PNG_EMPTY);
972 #endif
973
974 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
975 png_bytep data, png_size_t length),PNG_EMPTY);
976
977 #ifdef PNG_WRITE_FLUSH_SUPPORTED
978 # ifdef PNG_STDIO_SUPPORTED
979 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
980 PNG_EMPTY);
981 # endif
982 #endif
983
984 /* Reset the CRC variable */
985 PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
986
987 /* Write the "data" buffer to whatever output you are using */
988 PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
989 png_const_bytep data, png_size_t length),PNG_EMPTY);
990
991 /* Read and check the PNG file signature */
992 PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
993 png_inforp info_ptr),PNG_EMPTY);
994
995 /* Read the chunk header (length + type name) */
996 PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
997 PNG_EMPTY);
998
999 /* Read data from whatever input you are using into the "data" buffer */
1000 PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
1001 png_size_t length),PNG_EMPTY);
1002
1003 /* Read bytes into buf, and update png_ptr->crc */
1004 PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
1005 png_uint_32 length),PNG_EMPTY);
1006
1007 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
1008 PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
1009 png_uint_32 skip),PNG_EMPTY);
1010
1011 /* Read the CRC from the file and compare it to the libpng calculated CRC */
1012 PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
1013
1014 /* Calculate the CRC over a section of data. Note that we are only
1015 * passing a maximum of 64K on systems that have this as a memory limit,
1016 * since this is the maximum buffer size we can specify.
1017 */
1018 PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
1019 png_const_bytep ptr, png_size_t length),PNG_EMPTY);
1020
1021 #ifdef PNG_WRITE_FLUSH_SUPPORTED
1022 PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
1023 #endif
1024
1025 /* Write various chunks */
1026
1027 /* Write the IHDR chunk, and update the png_struct with the necessary
1028 * information.
1029 */
1030 PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
1031 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
1032 int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
1033
1034 PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
1035 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
1036
1037 PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
1038 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
1039 PNG_EMPTY);
1040
1041 PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
1042
1043 #ifdef PNG_WRITE_gAMA_SUPPORTED
1044 PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
1045 png_fixed_point file_gamma),PNG_EMPTY);
1046 #endif
1047
1048 #ifdef PNG_WRITE_sBIT_SUPPORTED
1049 PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
1050 png_const_color_8p sbit, int color_type),PNG_EMPTY);
1051 #endif
1052
1053 #ifdef PNG_WRITE_cHRM_SUPPORTED
1054 PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
1055 const png_xy *xy), PNG_EMPTY);
1056 /* The xy value must have been previously validated */
1057 #endif
1058
1059 #ifdef PNG_WRITE_sRGB_SUPPORTED
1060 PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
1061 int intent),PNG_EMPTY);
1062 #endif
1063
1064 #ifdef PNG_WRITE_iCCP_SUPPORTED
1065 PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
1066 png_const_charp name, png_const_bytep profile), PNG_EMPTY);
1067 /* The profile must have been previously validated for correctness, the
1068 * length comes from the first four bytes. Only the base, deflate,
1069 * compression is supported.
1070 */
1071 #endif
1072
1073 #ifdef PNG_WRITE_sPLT_SUPPORTED
1074 PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
1075 png_const_sPLT_tp palette),PNG_EMPTY);
1076 #endif
1077
1078 #ifdef PNG_WRITE_tRNS_SUPPORTED
1079 PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
1080 png_const_bytep trans, png_const_color_16p values, int number,
1081 int color_type),PNG_EMPTY);
1082 #endif
1083
1084 #ifdef PNG_WRITE_bKGD_SUPPORTED
1085 PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
1086 png_const_color_16p values, int color_type),PNG_EMPTY);
1087 #endif
1088
1089 #ifdef PNG_WRITE_hIST_SUPPORTED
1090 PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
1091 png_const_uint_16p hist, int num_hist),PNG_EMPTY);
1092 #endif
1093
1094 /* Chunks that have keywords */
1095 #ifdef PNG_WRITE_tEXt_SUPPORTED
1096 PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
1097 png_const_charp key, png_const_charp text, png_size_t text_len),PNG_EMPTY);
1098 #endif
1099
1100 #ifdef PNG_WRITE_zTXt_SUPPORTED
1101 PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
1102 key, png_const_charp text, int compression),PNG_EMPTY);
1103 #endif
1104
1105 #ifdef PNG_WRITE_iTXt_SUPPORTED
1106 PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
1107 int compression, png_const_charp key, png_const_charp lang,
1108 png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
1109 #endif
1110
1111 #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
1112 PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
1113 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
1114 #endif
1115
1116 #ifdef PNG_WRITE_oFFs_SUPPORTED
1117 PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
1118 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
1119 #endif
1120
1121 #ifdef PNG_WRITE_pCAL_SUPPORTED
1122 PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
1123 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
1124 png_const_charp units, png_charpp params),PNG_EMPTY);
1125 #endif
1126
1127 #ifdef PNG_WRITE_pHYs_SUPPORTED
1128 PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
1129 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
1130 int unit_type),PNG_EMPTY);
1131 #endif
1132
1133 #ifdef PNG_WRITE_tIME_SUPPORTED
1134 PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
1135 png_const_timep mod_time),PNG_EMPTY);
1136 #endif
1137
1138 #ifdef PNG_WRITE_sCAL_SUPPORTED
1139 PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
1140 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
1141 #endif
1142
1143 /* Called when finished processing a row of data */
1144 PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
1145 PNG_EMPTY);
1146
1147 /* Internal use only. Called before first row of data */
1148 PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
1149 PNG_EMPTY);
1150
1151 /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
1152 * array of png_ptr->width pixels. If the image is not interlaced or this
1153 * is the final pass this just does a memcpy, otherwise the "display" flag
1154 * is used to determine whether to copy pixels that are not in the current pass.
1155 *
1156 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
1157 * function to achieve the documented 'blocky' appearance during interlaced read
1158 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
1159 * are not changed if they are not in the current pass, when display is 0.
1160 *
1161 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
1162 *
1163 * The API always reads from the png_struct row buffer and always assumes that
1164 * it is full width (png_do_read_interlace has already been called.)
1165 *
1166 * This function is only ever used to write to row buffers provided by the
1167 * caller of the relevant libpng API and the row must have already been
1168 * transformed by the read transformations.
1169 *
1170 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
1171 * bitmasks for use within the code, otherwise runtime generated masks are used.
1172 * The default is compile time masks.
1173 */
1174 #ifndef PNG_USE_COMPILE_TIME_MASKS
1175 # define PNG_USE_COMPILE_TIME_MASKS 1
1176 #endif
1177 PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
1178 png_bytep row, int display),PNG_EMPTY);
1179
1180 #ifdef PNG_READ_INTERLACING_SUPPORTED
1181 /* Expand an interlaced row: the 'row_info' describes the pass data that has
1182 * been read in and must correspond to the pixels in 'row', the pixels are
1183 * expanded (moved apart) in 'row' to match the final layout, when doing this
1184 * the pixels are *replicated* to the intervening space. This is essential for
1185 * the correct operation of png_combine_row, above.
1186 */
1187 PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
1188 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
1189 #endif
1190
1191 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
1192
1193 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
1194 /* Grab pixels out of a row for an interlaced pass */
1195 PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
1196 png_bytep row, int pass),PNG_EMPTY);
1197 #endif
1198
1199 /* Unfilter a row: check the filter value before calling this, there is no point
1200 * calling it for PNG_FILTER_VALUE_NONE.
1201 */
1202 PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
1203 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
1204
1205 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
1206 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1207 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
1208 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1209 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
1210 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1211 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
1212 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1213 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
1214 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1215 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
1216 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1217 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
1218 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1219
1220 /* Choose the best filter to use and filter the row data */
1221 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
1222 png_row_infop row_info),PNG_EMPTY);
1223
1224 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1225 PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
1226 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
1227 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer
1228 * is NULL the function checks, instead, for the end of the stream. In this
1229 * case a benign error will be issued if the stream end is not found or if
1230 * extra data has to be consumed.
1231 */
1232 PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
1233 PNG_EMPTY);
1234 /* This cleans up when the IDAT LZ stream does not end when the last image
1235 * byte is read; there is still some pending input.
1236 */
1237
1238 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
1239 PNG_EMPTY);
1240 /* Finish a row while reading, dealing with interlacing passes, etc. */
1241 #endif /* SEQUENTIAL_READ */
1242
1243 /* Initialize the row buffers, etc. */
1244 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
1245
1246 #if PNG_ZLIB_VERNUM >= 0x1240
1247 PNG_INTERNAL_FUNCTION(int,png_zlib_inflate,(png_structrp png_ptr, int flush),
1248 PNG_EMPTY);
1249 # define PNG_INFLATE(pp, flush) png_zlib_inflate(pp, flush)
1250 #else /* Zlib < 1.2.4 */
1251 # define PNG_INFLATE(pp, flush) inflate(&(pp)->zstream, flush)
1252 #endif /* Zlib < 1.2.4 */
1253
1254 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1255 /* Optional call to update the users info structure */
1256 PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
1257 png_inforp info_ptr),PNG_EMPTY);
1258 #endif
1259
1260 /* Shared transform functions, defined in pngtran.c */
1261 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1262 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1263 PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
1264 png_bytep row, int at_start),PNG_EMPTY);
1265 #endif
1266
1267 #ifdef PNG_16BIT_SUPPORTED
1268 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1269 PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
1270 png_bytep row),PNG_EMPTY);
1271 #endif
1272 #endif
1273
1274 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1275 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1276 PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
1277 png_bytep row),PNG_EMPTY);
1278 #endif
1279
1280 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1281 PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
1282 png_bytep row),PNG_EMPTY);
1283 #endif
1284
1285 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1286 PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
1287 png_bytep row),PNG_EMPTY);
1288 #endif
1289
1290 /* The following decodes the appropriate chunks, and does error correction,
1291 * then calls the appropriate callback for the chunk if it is valid.
1292 */
1293
1294 /* Decode the IHDR chunk */
1295 PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
1296 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1297 PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
1298 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1299 PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
1300 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1301
1302 #ifdef PNG_READ_bKGD_SUPPORTED
1303 PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
1304 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1305 #endif
1306
1307 #ifdef PNG_READ_cHRM_SUPPORTED
1308 PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
1309 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1310 #endif
1311
1312 #ifdef PNG_READ_gAMA_SUPPORTED
1313 PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
1314 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1315 #endif
1316
1317 #ifdef PNG_READ_hIST_SUPPORTED
1318 PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
1319 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1320 #endif
1321
1322 #ifdef PNG_READ_iCCP_SUPPORTED
1323 PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
1324 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1325 #endif /* READ_iCCP */
1326
1327 #ifdef PNG_READ_iTXt_SUPPORTED
1328 PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
1329 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1330 #endif
1331
1332 #ifdef PNG_READ_oFFs_SUPPORTED
1333 PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
1334 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1335 #endif
1336
1337 #ifdef PNG_READ_pCAL_SUPPORTED
1338 PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
1339 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1340 #endif
1341
1342 #ifdef PNG_READ_pHYs_SUPPORTED
1343 PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
1344 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1345 #endif
1346
1347 #ifdef PNG_READ_sBIT_SUPPORTED
1348 PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
1349 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1350 #endif
1351
1352 #ifdef PNG_READ_sCAL_SUPPORTED
1353 PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
1354 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1355 #endif
1356
1357 #ifdef PNG_READ_sPLT_SUPPORTED
1358 PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
1359 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1360 #endif /* READ_sPLT */
1361
1362 #ifdef PNG_READ_sRGB_SUPPORTED
1363 PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
1364 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1365 #endif
1366
1367 #ifdef PNG_READ_tEXt_SUPPORTED
1368 PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
1369 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1370 #endif
1371
1372 #ifdef PNG_READ_tIME_SUPPORTED
1373 PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
1374 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1375 #endif
1376
1377 #ifdef PNG_READ_tRNS_SUPPORTED
1378 PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
1379 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1380 #endif
1381
1382 #ifdef PNG_READ_zTXt_SUPPORTED
1383 PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
1384 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1385 #endif
1386
1387 PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr,
1388 png_uint_32 chunk_name),PNG_EMPTY);
1389
1390 PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
1391 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
1392 /* This is the function that gets called for unknown chunks. The 'keep'
1393 * argument is either non-zero for a known chunk that has been set to be
1394 * handled as unknown or zero for an unknown chunk. By default the function
1395 * just skips the chunk or errors out if it is critical.
1396 */
1397
1398 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
1399 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
1400 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
1401 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
1402 /* Exactly as the API png_handle_as_unknown() except that the argument is a
1403 * 32-bit chunk name, not a string.
1404 */
1405 #endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
1406
1407 /* Handle the transformations for reading and writing */
1408 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1409 PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
1410 png_row_infop row_info),PNG_EMPTY);
1411 #endif
1412 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1413 PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
1414 png_row_infop row_info),PNG_EMPTY);
1415 #endif
1416
1417 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1418 PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
1419 PNG_EMPTY);
1420 #endif
1421
1422 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1423 PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
1424 png_inforp info_ptr),PNG_EMPTY);
1425 PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
1426 png_inforp info_ptr),PNG_EMPTY);
1427 PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
1428 PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
1429 PNG_EMPTY);
1430 PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
1431 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
1432 PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
1433 PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
1434 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
1435 PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
1436 PNG_EMPTY);
1437 PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
1438 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1439 PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
1440 png_inforp info_ptr),PNG_EMPTY);
1441 PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
1442 png_inforp info_ptr),PNG_EMPTY);
1443 PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
1444 png_bytep row),PNG_EMPTY);
1445 PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
1446 png_inforp info_ptr),PNG_EMPTY);
1447 PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
1448 png_inforp info_ptr),PNG_EMPTY);
1449 PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
1450 PNG_EMPTY);
1451 # ifdef PNG_READ_tEXt_SUPPORTED
1452 PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
1453 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1454 PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
1455 png_inforp info_ptr),PNG_EMPTY);
1456 # endif
1457 # ifdef PNG_READ_zTXt_SUPPORTED
1458 PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
1459 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1460 PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
1461 png_inforp info_ptr),PNG_EMPTY);
1462 # endif
1463 # ifdef PNG_READ_iTXt_SUPPORTED
1464 PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
1465 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1466 PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
1467 png_inforp info_ptr),PNG_EMPTY);
1468 # endif
1469
1470 #endif /* PROGRESSIVE_READ */
1471
1472 /* Added at libpng version 1.6.0 */
1473 #ifdef PNG_GAMMA_SUPPORTED
1474 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
1475 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
1476 /* Set the colorspace gamma with a value provided by the application or by
1477 * the gAMA chunk on read. The value will override anything set by an ICC
1478 * profile.
1479 */
1480
1481 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
1482 png_inforp info_ptr), PNG_EMPTY);
1483 /* Synchronize the info 'valid' flags with the colorspace */
1484
1485 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
1486 png_inforp info_ptr), PNG_EMPTY);
1487 /* Copy the png_struct colorspace to the info_struct and call the above to
1488 * synchronize the flags. Checks for NULL info_ptr and does nothing.
1489 */
1490 #endif
1491
1492 /* Added at libpng version 1.4.0 */
1493 #ifdef PNG_COLORSPACE_SUPPORTED
1494 /* These internal functions are for maintaining the colorspace structure within
1495 * a png_info or png_struct (or, indeed, both).
1496 */
1497 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
1498 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
1499 int preferred), PNG_EMPTY);
1500
1501 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
1502 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
1503 int preferred), PNG_EMPTY);
1504
1505 #ifdef PNG_sRGB_SUPPORTED
1506 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
1507 png_colorspacerp colorspace, int intent), PNG_EMPTY);
1508 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
1509 * flags to write them, if it returns false there was a problem and an error
1510 * message has already been output (but the colorspace may still need to be
1511 * synced to record the invalid flag).
1512 */
1513 #endif /* sRGB */
1514
1515 #ifdef PNG_iCCP_SUPPORTED
1516 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
1517 png_colorspacerp colorspace, png_const_charp name,
1518 png_uint_32 profile_length, png_const_bytep profile, int color_type),
1519 PNG_EMPTY);
1520 /* The 'name' is used for information only */
1521
1522 /* Routines for checking parts of an ICC profile. */
1523 PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
1524 png_colorspacerp colorspace, png_const_charp name,
1525 png_uint_32 profile_length), PNG_EMPTY);
1526 PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
1527 png_colorspacerp colorspace, png_const_charp name,
1528 png_uint_32 profile_length,
1529 png_const_bytep profile /* first 132 bytes only */, int color_type),
1530 PNG_EMPTY);
1531 PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
1532 png_colorspacerp colorspace, png_const_charp name,
1533 png_uint_32 profile_length,
1534 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
1535 #ifdef PNG_sRGB_SUPPORTED
1536 PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
1537 png_const_structrp png_ptr, png_colorspacerp colorspace,
1538 png_const_bytep profile, uLong adler), PNG_EMPTY);
1539 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
1540 * be zero to indicate that it is not available. It is used, if provided,
1541 * as a fast check on the profile when checking to see if it is sRGB.
1542 */
1543 #endif
1544 #endif /* iCCP */
1545
1546 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1547 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
1548 (png_structrp png_ptr), PNG_EMPTY);
1549 /* Set the rgb_to_gray coefficients from the colorspace Y values */
1550 #endif /* READ_RGB_TO_GRAY */
1551 #endif /* COLORSPACE */
1552
1553 /* Added at libpng version 1.4.0 */
1554 PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
1555 png_uint_32 width, png_uint_32 height, int bit_depth,
1556 int color_type, int interlace_type, int compression_type,
1557 int filter_type),PNG_EMPTY);
1558
1559 /* Added at libpng version 1.5.10 */
1560 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
1561 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
1562 PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
1563 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
1564 #endif
1565
1566 #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1567 PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
1568 png_const_charp name),PNG_NORETURN);
1569 #endif
1570
1571 /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1572 * the end. Always leaves the buffer nul terminated. Never errors out (and
1573 * there is no error code.)
1574 */
1575 PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
1576 size_t pos, png_const_charp string),PNG_EMPTY);
1577
1578 /* Various internal functions to handle formatted warning messages, currently
1579 * only implemented for warnings.
1580 */
1581 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1582 /* Utility to dump an unsigned value into a buffer, given a start pointer and
1583 * and end pointer (which should point just *beyond* the end of the buffer!)
1584 * Returns the pointer to the start of the formatted string. This utility only
1585 * does unsigned values.
1586 */
1587 PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
1588 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
1589
1590 /* Convenience macro that takes an array: */
1591 #define PNG_FORMAT_NUMBER(buffer,format,number) \
1592 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1593
1594 /* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1595 #define PNG_NUMBER_BUFFER_SIZE 24
1596
1597 /* These are the integer formats currently supported, the name is formed from
1598 * the standard printf(3) format string.
1599 */
1600 #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1601 #define PNG_NUMBER_FORMAT_02u 2
1602 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1603 #define PNG_NUMBER_FORMAT_02d 2
1604 #define PNG_NUMBER_FORMAT_x 3
1605 #define PNG_NUMBER_FORMAT_02x 4
1606 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1607 #endif
1608
1609 #ifdef PNG_WARNINGS_SUPPORTED
1610 /* New defines and members adding in libpng-1.5.4 */
1611 # define PNG_WARNING_PARAMETER_SIZE 32
1612 # define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
1613
1614 /* An l-value of this type has to be passed to the APIs below to cache the
1615 * values of the parameters to a formatted warning message.
1616 */
1617 typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1618 PNG_WARNING_PARAMETER_SIZE];
1619
1620 PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
1621 int number, png_const_charp string),PNG_EMPTY);
1622 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1623 * including the trailing '\0'.
1624 */
1625 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
1626 (png_warning_parameters p, int number, int format, png_alloc_size_t value),
1627 PNG_EMPTY);
1628 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1629 * need to output. Use the following for a signed value.
1630 */
1631 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
1632 (png_warning_parameters p, int number, int format, png_int_32 value),
1633 PNG_EMPTY);
1634
1635 PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
1636 png_warning_parameters p, png_const_charp message),PNG_EMPTY);
1637 /* 'message' follows the X/Open approach of using @1, @2 to insert
1638 * parameters previously supplied using the above functions. Errors in
1639 * specifying the parameters will simply result in garbage substitutions.
1640 */
1641 #endif
1642
1643 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
1644 /* Application errors (new in 1.6); use these functions (declared below) for
1645 * errors in the parameters or order of API function calls on read. The
1646 * 'warning' should be used for an error that can be handled completely; the
1647 * 'error' for one which can be handled safely but which may lose application
1648 * information or settings.
1649 *
1650 * By default these both result in a png_error call prior to release, while in a
1651 * released version the 'warning' is just a warning. However if the application
1652 * explicitly disables benign errors (explicitly permitting the code to lose
1653 * information) they both turn into warnings.
1654 *
1655 * If benign errors aren't supported they end up as the corresponding base call
1656 * (png_warning or png_error.)
1657 */
1658 PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
1659 png_const_charp message),PNG_EMPTY);
1660 /* The application provided invalid parameters to an API function or called
1661 * an API function at the wrong time, libpng can completely recover.
1662 */
1663
1664 PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
1665 png_const_charp message),PNG_EMPTY);
1666 /* As above but libpng will ignore the call, or attempt some other partial
1667 * recovery from the error.
1668 */
1669 #else
1670 # define png_app_warning(pp,s) png_warning(pp,s)
1671 # define png_app_error(pp,s) png_error(pp,s)
1672 #endif
1673
1674 PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
1675 png_const_charp message, int error),PNG_EMPTY);
1676 /* Report a recoverable issue in chunk data. On read this is used to report
1677 * a problem found while reading a particular chunk and the
1678 * png_chunk_benign_error or png_chunk_warning function is used as
1679 * appropriate. On write this is used to report an error that comes from
1680 * data set via an application call to a png_set_ API and png_app_error or
1681 * png_app_warning is used as appropriate.
1682 *
1683 * The 'error' parameter must have one of the following values:
1684 */
1685 #define PNG_CHUNK_WARNING 0 /* never an error */
1686 #define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
1687 #define PNG_CHUNK_ERROR 2 /* always an error */
1688
1689 /* ASCII to FP interfaces, currently only implemented if sCAL
1690 * support is required.
1691 */
1692 #if defined(PNG_sCAL_SUPPORTED)
1693 /* MAX_DIGITS is actually the maximum number of characters in an sCAL
1694 * width or height, derived from the precision (number of significant
1695 * digits - a build time settable option) and assumptions about the
1696 * maximum ridiculous exponent.
1697 */
1698 #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1699
1700 #ifdef PNG_FLOATING_POINT_SUPPORTED
1701 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
1702 png_charp ascii, png_size_t size, double fp, unsigned int precision),
1703 PNG_EMPTY);
1704 #endif /* FLOATING_POINT */
1705
1706 #ifdef PNG_FIXED_POINT_SUPPORTED
1707 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
1708 png_charp ascii, png_size_t size, png_fixed_point fp),PNG_EMPTY);
1709 #endif /* FIXED_POINT */
1710 #endif /* sCAL */
1711
1712 #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1713 /* An internal API to validate the format of a floating point number.
1714 * The result is the index of the next character. If the number is
1715 * not valid it will be the index of a character in the supposed number.
1716 *
1717 * The format of a number is defined in the PNG extensions specification
1718 * and this API is strictly conformant to that spec, not anyone elses!
1719 *
1720 * The format as a regular expression is:
1721 *
1722 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1723 *
1724 * or:
1725 *
1726 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1727 *
1728 * The complexity is that either integer or fraction must be present and the
1729 * fraction is permitted to have no digits only if the integer is present.
1730 *
1731 * NOTE: The dangling E problem.
1732 * There is a PNG valid floating point number in the following:
1733 *
1734 * PNG floating point numbers are not greedy.
1735 *
1736 * Working this out requires *TWO* character lookahead (because of the
1737 * sign), the parser does not do this - it will fail at the 'r' - this
1738 * doesn't matter for PNG sCAL chunk values, but it requires more care
1739 * if the value were ever to be embedded in something more complex. Use
1740 * ANSI-C strtod if you need the lookahead.
1741 */
1742 /* State table for the parser. */
1743 #define PNG_FP_INTEGER 0 /* before or in integer */
1744 #define PNG_FP_FRACTION 1 /* before or in fraction */
1745 #define PNG_FP_EXPONENT 2 /* before or in exponent */
1746 #define PNG_FP_STATE 3 /* mask for the above */
1747 #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1748 #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1749 #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1750 #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1751 #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1752
1753 /* These three values don't affect the parser. They are set but not used.
1754 */
1755 #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1756 #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1757 #define PNG_FP_NONZERO 256 /* A non-zero value */
1758 #define PNG_FP_STICKY 448 /* The above three flags */
1759
1760 /* This is available for the caller to store in 'state' if required. Do not
1761 * call the parser after setting it (the parser sometimes clears it.)
1762 */
1763 #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1764
1765 /* Result codes for the parser (boolean - true meants ok, false means
1766 * not ok yet.)
1767 */
1768 #define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1769 #define PNG_FP_OK 1 /* The number is valid */
1770
1771 /* Tests on the sticky non-zero and negative flags. To pass these checks
1772 * the state must also indicate that the whole number is valid - this is
1773 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1774 * is equivalent to PNG_FP_OK above.)
1775 */
1776 #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1777 /* NZ_MASK: the string is valid and a non-zero negative value */
1778 #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
1779 /* Z MASK: the string is valid and a non-zero value. */
1780 /* PNG_FP_SAW_DIGIT: the string is valid. */
1781 #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
1782 #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
1783 #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
1784
1785 /* The actual parser. This can be called repeatedly. It updates
1786 * the index into the string and the state variable (which must
1787 * be initialized to 0). It returns a result code, as above. There
1788 * is no point calling the parser any more if it fails to advance to
1789 * the end of the string - it is stuck on an invalid character (or
1790 * terminated by '\0').
1791 *
1792 * Note that the pointer will consume an E or even an E+ and then leave
1793 * a 'maybe' state even though a preceding integer.fraction is valid.
1794 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
1795 * a valid number. It's possible to recover from this by calling
1796 * the parser again (from the start, with state 0) but with a string
1797 * that omits the last character (i.e. set the size to the index of
1798 * the problem character.) This has not been tested within libpng.
1799 */
1800 PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
1801 png_size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
1802
1803 /* This is the same but it checks a complete string and returns true
1804 * only if it just contains a floating point number. As of 1.5.4 this
1805 * function also returns the state at the end of parsing the number if
1806 * it was valid (otherwise it returns 0.) This can be used for testing
1807 * for negative or zero values using the sticky flag.
1808 */
1809 PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
1810 png_size_t size),PNG_EMPTY);
1811 #endif /* pCAL || sCAL */
1812
1813 #if defined(PNG_GAMMA_SUPPORTED) ||\
1814 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
1815 /* Added at libpng version 1.5.0 */
1816 /* This is a utility to provide a*times/div (rounded) and indicate
1817 * if there is an overflow. The result is a boolean - false (0)
1818 * for overflow, true (1) if no overflow, in which case *res
1819 * holds the result.
1820 */
1821 PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
1822 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
1823 #endif
1824
1825 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
1826 /* Same deal, but issue a warning on overflow and return 0. */
1827 PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
1828 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
1829 png_int_32 divided_by),PNG_EMPTY);
1830 #endif
1831
1832 #ifdef PNG_GAMMA_SUPPORTED
1833 /* Calculate a reciprocal - used for gamma values. This returns
1834 * 0 if the argument is 0 in order to maintain an undefined value;
1835 * there are no warnings.
1836 */
1837 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
1838 PNG_EMPTY);
1839
1840 #ifdef PNG_READ_GAMMA_SUPPORTED
1841 /* The same but gives a reciprocal of the product of two fixed point
1842 * values. Accuracy is suitable for gamma calculations but this is
1843 * not exact - use png_muldiv for that. Only required at present on read.
1844 */
1845 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
1846 png_fixed_point b),PNG_EMPTY);
1847 #endif
1848
1849 /* Return true if the gamma value is significantly different from 1.0 */
1850 PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
1851 PNG_EMPTY);
1852 #endif
1853
1854 #ifdef PNG_READ_GAMMA_SUPPORTED
1855 /* Internal fixed point gamma correction. These APIs are called as
1856 * required to convert single values - they don't need to be fast,
1857 * they are not used when processing image pixel values.
1858 *
1859 * While the input is an 'unsigned' value it must actually be the
1860 * correct bit value - 0..255 or 0..65535 as required.
1861 */
1862 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
1863 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
1864 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
1865 png_fixed_point gamma_value),PNG_EMPTY);
1866 PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
1867 png_fixed_point gamma_value),PNG_EMPTY);
1868 PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
1869 PNG_EMPTY);
1870 PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
1871 int bit_depth),PNG_EMPTY);
1872 #endif
1873
1874 /* SIMPLIFIED READ/WRITE SUPPORT */
1875 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
1876 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
1877 /* The internal structure that png_image::opaque points to. */
1878 typedef struct png_control
1879 {
1880 png_structp png_ptr;
1881 png_infop info_ptr;
1882 png_voidp error_buf; /* Always a jmp_buf at present. */
1883
1884 png_const_bytep memory; /* Memory buffer. */
1885 png_size_t size; /* Size of the memory buffer. */
1886
1887 unsigned int for_write :1; /* Otherwise it is a read structure */
1888 unsigned int owned_file :1; /* We own the file in io_ptr */
1889 } png_control;
1890
1891 /* Return the pointer to the jmp_buf from a png_control: necessary because C
1892 * does not reveal the type of the elements of jmp_buf.
1893 */
1894 #ifdef __cplusplus
1895 # define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
1896 #else
1897 # define png_control_jmp_buf(pc) ((pc)->error_buf)
1898 #endif
1899
1900 /* Utility to safely execute a piece of libpng code catching and logging any
1901 * errors that might occur. Returns true on success, false on failure (either
1902 * of the function or as a result of a png_error.)
1903 */
1904 PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr,
1905 png_const_charp error_message),PNG_NORETURN);
1906
1907 #ifdef PNG_WARNINGS_SUPPORTED
1908 PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr,
1909 png_const_charp warning_message),PNG_EMPTY);
1910 #else
1911 # define png_safe_warning 0/*dummy argument*/
1912 #endif
1913
1914 PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
1915 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
1916
1917 /* Utility to log an error; this also cleans up the png_image; the function
1918 * always returns 0 (false).
1919 */
1920 PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
1921 png_const_charp error_message),PNG_EMPTY);
1922
1923 #ifndef PNG_SIMPLIFIED_READ_SUPPORTED
1924 /* png_image_free is used by the write code but not exported */
1925 PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
1926 #endif /* !SIMPLIFIED_READ */
1927
1928 #endif /* SIMPLIFIED READ/WRITE */
1929
1930 /* These are initialization functions for hardware specific PNG filter
1931 * optimizations; list these here then select the appropriate one at compile
1932 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
1933 * the generic code is used.
1934 */
1935 #ifdef PNG_FILTER_OPTIMIZATIONS
1936 PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
1937 unsigned int bpp), PNG_EMPTY);
1938 /* Just declare the optimization that will be used */
1939 #else
1940 /* List *all* the possible optimizations here - this branch is required if
1941 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
1942 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
1943 */
1944 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
1945 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
1946 #endif
1947
1948 PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
1949 png_const_charp key, png_bytep new_key), PNG_EMPTY);
1950
1951 /* Maintainer: Put new private prototypes here ^ */
1952
1953 #include "pngdebug.h"
1954
1955 #ifdef __cplusplus
1956 }
1957 #endif
1958
1959 #endif /* PNG_VERSION_INFO_ONLY */
1960 #endif /* PNGPRIV_H */