[LIBPNG] Update to v1.6.21. CORE-11128
[reactos.git] / reactos / dll / 3rdparty / libpng / pngpriv.h
1
2 /* pngpriv.h - private declarations for use inside libpng
3 *
4 * Last changed in libpng 1.6.21 [January 15, 2016]
5 * Copyright (c) 1998-2002,2004,2006-2015 Glenn Randers-Pehrson
6 * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
7 * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
8 *
9 * This code is released under the libpng license.
10 * For conditions of distribution and use, see the disclaimer
11 * and license in png.h
12 */
13
14 /* The symbols declared in this file (including the functions declared
15 * as extern) are PRIVATE. They are not part of the libpng public
16 * interface, and are not recommended for use by regular applications.
17 * Some of them may become public in the future; others may stay private,
18 * change in an incompatible way, or even disappear.
19 * Although the libpng users are not forbidden to include this header,
20 * they should be well aware of the issues that may arise from doing so.
21 */
22
23 #ifndef PNGPRIV_H
24 #define PNGPRIV_H
25
26 /* Feature Test Macros. The following are defined here to ensure that correctly
27 * implemented libraries reveal the APIs libpng needs to build and hide those
28 * that are not needed and potentially damaging to the compilation.
29 *
30 * Feature Test Macros must be defined before any system header is included (see
31 * POSIX 1003.1 2.8.2 "POSIX Symbols."
32 *
33 * These macros only have an effect if the operating system supports either
34 * POSIX 1003.1 or C99, or both. On other operating systems (particularly
35 * Windows/Visual Studio) there is no effect; the OS specific tests below are
36 * still required (as of 2011-05-02.)
37 */
38 #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
39
40 #ifndef PNG_VERSION_INFO_ONLY
41 /* Standard library headers not required by png.h: */
42 # include <stdlib.h>
43 # include <string.h>
44 #endif
45
46 #define PNGLIB_BUILD /*libpng is being built, not used*/
47
48 /* If HAVE_CONFIG_H is defined during the build then the build system must
49 * provide an appropriate "config.h" file on the include path. The header file
50 * must provide definitions as required below (search for "HAVE_CONFIG_H");
51 * see configure.ac for more details of the requirements. The macro
52 * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on
53 * 'configure'; define this macro to prevent the configure build including the
54 * configure generated config.h. Libpng is expected to compile without *any*
55 * special build system support on a reasonably ANSI-C compliant system.
56 */
57 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
58 # include <config.h>
59
60 /* Pick up the definition of 'restrict' from config.h if it was read: */
61 # define PNG_RESTRICT restrict
62 #endif
63
64 /* To support symbol prefixing it is necessary to know *before* including png.h
65 * whether the fixed point (and maybe other) APIs are exported, because if they
66 * are not internal definitions may be required. This is handled below just
67 * before png.h is included, but load the configuration now if it is available.
68 */
69 #ifndef PNGLCONF_H
70 # include "pnglibconf.h"
71 #endif
72
73 /* Local renames may change non-exported API functions from png.h */
74 #if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
75 # include "pngprefix.h"
76 #endif
77
78 #ifdef PNG_USER_CONFIG
79 # include "pngusr.h"
80 /* These should have been defined in pngusr.h */
81 # ifndef PNG_USER_PRIVATEBUILD
82 # define PNG_USER_PRIVATEBUILD "Custom libpng build"
83 # endif
84 # ifndef PNG_USER_DLLFNAME_POSTFIX
85 # define PNG_USER_DLLFNAME_POSTFIX "Cb"
86 # endif
87 #endif
88
89 /* Compile time options.
90 * =====================
91 * In a multi-arch build the compiler may compile the code several times for the
92 * same object module, producing different binaries for different architectures.
93 * When this happens configure-time setting of the target host options cannot be
94 * done and this interferes with the handling of the ARM NEON optimizations, and
95 * possibly other similar optimizations. Put additional tests here; in general
96 * this is needed when the same option can be changed at both compile time and
97 * run time depending on the target OS (i.e. iOS vs Android.)
98 *
99 * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
100 * this is not possible with certain compilers (Oracle SUN OS CC), as a result
101 * it is necessary to ensure that all extern functions that *might* be used
102 * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__
103 * below is one example of this behavior because it is controlled by the
104 * presence or not of -mfpu=neon on the GCC command line, it is possible to do
105 * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
106 * do this.
107 */
108 #ifndef PNG_ARM_NEON_OPT
109 /* ARM NEON optimizations are being controlled by the compiler settings,
110 * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon
111 * with GCC) then the compiler will define __ARM_NEON__ and we can rely
112 * unconditionally on NEON instructions not crashing, otherwise we must
113 * disable use of NEON instructions.
114 *
115 * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they
116 * can only be turned on automatically if that is supported too. If
117 * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail
118 * to compile with an appropriate #error if ALIGNED_MEMORY has been turned
119 * off.
120 *
121 * Note that gcc-4.9 defines __ARM_NEON instead of the deprecated
122 * __ARM_NEON__, so we check both variants.
123 *
124 * To disable ARM_NEON optimizations entirely, and skip compiling the
125 * associated assembler code, pass --enable-arm-neon=no to configure
126 * or put -DPNG_ARM_NEON_OPT=0 in CPPFLAGS.
127 */
128 # if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \
129 defined(PNG_ALIGNED_MEMORY_SUPPORTED)
130 # define PNG_ARM_NEON_OPT 2
131 # else
132 # define PNG_ARM_NEON_OPT 0
133 # endif
134 #endif
135
136 #if PNG_ARM_NEON_OPT > 0
137 /* NEON optimizations are to be at least considered by libpng, so enable the
138 * callbacks to do this.
139 */
140 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
141
142 /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used
143 * if possible - if __ARM_NEON__ is set and the compiler version is not known
144 * to be broken. This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can
145 * be:
146 *
147 * 1 The intrinsics code (the default with __ARM_NEON__)
148 * 2 The hand coded assembler (the default without __ARM_NEON__)
149 *
150 * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however
151 * this is *NOT* supported and may cease to work even after a minor revision
152 * to libpng. It *is* valid to do this for testing purposes, e.g. speed
153 * testing or a new compiler, but the results should be communicated to the
154 * libpng implementation list for incorporation in the next minor release.
155 */
156 # ifndef PNG_ARM_NEON_IMPLEMENTATION
157 # if defined(__ARM_NEON__) || defined(__ARM_NEON)
158 # if defined(__clang__)
159 /* At present it is unknown by the libpng developers which versions
160 * of clang support the intrinsics, however some or perhaps all
161 * versions do not work with the assembler so this may be
162 * irrelevant, so just use the default (do nothing here.)
163 */
164 # elif defined(__GNUC__)
165 /* GCC 4.5.4 NEON support is known to be broken. 4.6.3 is known to
166 * work, so if this *is* GCC, or G++, look for a version >4.5
167 */
168 # if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6)
169 # define PNG_ARM_NEON_IMPLEMENTATION 2
170 # endif /* no GNUC support */
171 # endif /* __GNUC__ */
172 # else /* !defined __ARM_NEON__ */
173 /* The 'intrinsics' code simply won't compile without this -mfpu=neon:
174 */
175 # define PNG_ARM_NEON_IMPLEMENTATION 2
176 # endif /* __ARM_NEON__ */
177 # endif /* !PNG_ARM_NEON_IMPLEMENTATION */
178
179 # ifndef PNG_ARM_NEON_IMPLEMENTATION
180 /* Use the intrinsics code by default. */
181 # define PNG_ARM_NEON_IMPLEMENTATION 1
182 # endif
183 #endif /* PNG_ARM_NEON_OPT > 0 */
184
185 /* Is this a build of a DLL where compilation of the object modules requires
186 * different preprocessor settings to those required for a simple library? If
187 * so PNG_BUILD_DLL must be set.
188 *
189 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
190 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
191 * static library of libpng then link the DLL against that.
192 */
193 #ifndef PNG_BUILD_DLL
194 # ifdef DLL_EXPORT
195 /* This is set by libtool when files are compiled for a DLL; libtool
196 * always compiles twice, even on systems where it isn't necessary. Set
197 * PNG_BUILD_DLL in case it is necessary:
198 */
199 # define PNG_BUILD_DLL
200 # else
201 # ifdef _WINDLL
202 /* This is set by the Microsoft Visual Studio IDE in projects that
203 * build a DLL. It can't easily be removed from those projects (it
204 * isn't visible in the Visual Studio UI) so it is a fairly reliable
205 * indication that PNG_IMPEXP needs to be set to the DLL export
206 * attributes.
207 */
208 # define PNG_BUILD_DLL
209 # else
210 # ifdef __DLL__
211 /* This is set by the Borland C system when compiling for a DLL
212 * (as above.)
213 */
214 # define PNG_BUILD_DLL
215 # else
216 /* Add additional compiler cases here. */
217 # endif
218 # endif
219 # endif
220 #endif /* Setting PNG_BUILD_DLL if required */
221
222 /* See pngconf.h for more details: the builder of the library may set this on
223 * the command line to the right thing for the specific compilation system or it
224 * may be automagically set above (at present we know of no system where it does
225 * need to be set on the command line.)
226 *
227 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
228 * setting it to the "import" setting for a DLL build.
229 */
230 #ifndef PNG_IMPEXP
231 # ifdef PNG_BUILD_DLL
232 # define PNG_IMPEXP PNG_DLL_EXPORT
233 # else
234 /* Not building a DLL, or the DLL doesn't require specific export
235 * definitions.
236 */
237 # define PNG_IMPEXP
238 # endif
239 #endif
240
241 /* No warnings for private or deprecated functions in the build: */
242 #ifndef PNG_DEPRECATED
243 # define PNG_DEPRECATED
244 #endif
245 #ifndef PNG_PRIVATE
246 # define PNG_PRIVATE
247 #endif
248
249 /* Symbol preprocessing support.
250 *
251 * To enable listing global, but internal, symbols the following macros should
252 * always be used to declare an extern data or function object in this file.
253 */
254 #ifndef PNG_INTERNAL_DATA
255 # define PNG_INTERNAL_DATA(type, name, array) PNG_LINKAGE_DATA type name array
256 #endif
257
258 #ifndef PNG_INTERNAL_FUNCTION
259 # define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
260 PNG_LINKAGE_FUNCTION PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
261 #endif
262
263 #ifndef PNG_INTERNAL_CALLBACK
264 # define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\
265 PNG_LINKAGE_CALLBACK PNG_FUNCTION(type, (PNGCBAPI name), args,\
266 PNG_EMPTY attributes)
267 #endif
268
269 /* If floating or fixed point APIs are disabled they may still be compiled
270 * internally. To handle this make sure they are declared as the appropriate
271 * internal extern function (otherwise the symbol prefixing stuff won't work and
272 * the functions will be used without definitions.)
273 *
274 * NOTE: although all the API functions are declared here they are not all
275 * actually built! Because the declarations are still made it is necessary to
276 * fake out types that they depend on.
277 */
278 #ifndef PNG_FP_EXPORT
279 # ifndef PNG_FLOATING_POINT_SUPPORTED
280 # define PNG_FP_EXPORT(ordinal, type, name, args)\
281 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
282 # ifndef PNG_VERSION_INFO_ONLY
283 typedef struct png_incomplete png_double;
284 typedef png_double* png_doublep;
285 typedef const png_double* png_const_doublep;
286 typedef png_double** png_doublepp;
287 # endif
288 # endif
289 #endif
290 #ifndef PNG_FIXED_EXPORT
291 # ifndef PNG_FIXED_POINT_SUPPORTED
292 # define PNG_FIXED_EXPORT(ordinal, type, name, args)\
293 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
294 # endif
295 #endif
296
297 #include "png.h"
298
299 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
300 #ifndef PNG_DLL_EXPORT
301 # define PNG_DLL_EXPORT
302 #endif
303
304 /* This is a global switch to set the compilation for an installed system
305 * (a release build). It can be set for testing debug builds to ensure that
306 * they will compile when the build type is switched to RC or STABLE, the
307 * default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS
308 * with either:
309 *
310 * -DPNG_RELEASE_BUILD Turns on the release compile path
311 * -DPNG_RELEASE_BUILD=0 Turns it off
312 * or in your pngusr.h with
313 * #define PNG_RELEASE_BUILD=1 Turns on the release compile path
314 * #define PNG_RELEASE_BUILD=0 Turns it off
315 */
316 #ifndef PNG_RELEASE_BUILD
317 # define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC)
318 #endif
319
320 /* SECURITY and SAFETY:
321 *
322 * libpng is built with support for internal limits on image dimensions and
323 * memory usage. These are documented in scripts/pnglibconf.dfa of the
324 * source and recorded in the machine generated header file pnglibconf.h.
325 */
326
327 /* If you are running on a machine where you cannot allocate more
328 * than 64K of memory at once, uncomment this. While libpng will not
329 * normally need that much memory in a chunk (unless you load up a very
330 * large file), zlib needs to know how big of a chunk it can use, and
331 * libpng thus makes sure to check any memory allocation to verify it
332 * will fit into memory.
333 *
334 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
335 * same limit and pngconf.h (already included) sets the limit
336 * if certain operating systems are detected.
337 */
338 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
339 # define PNG_MAX_MALLOC_64K
340 #endif
341
342 #ifndef PNG_UNUSED
343 /* Unused formal parameter warnings are silenced using the following macro
344 * which is expected to have no bad effects on performance (optimizing
345 * compilers will probably remove it entirely). Note that if you replace
346 * it with something other than whitespace, you must include the terminating
347 * semicolon.
348 */
349 # define PNG_UNUSED(param) (void)param;
350 #endif
351
352 /* Just a little check that someone hasn't tried to define something
353 * contradictory.
354 */
355 #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
356 # undef PNG_ZBUF_SIZE
357 # define PNG_ZBUF_SIZE 65536L
358 #endif
359
360 /* If warnings or errors are turned off the code is disabled or redirected here.
361 * From 1.5.4 functions have been added to allow very limited formatting of
362 * error and warning messages - this code will also be disabled here.
363 */
364 #ifdef PNG_WARNINGS_SUPPORTED
365 # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
366 #else
367 # define png_warning_parameter(p,number,string) ((void)0)
368 # define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
369 # define png_warning_parameter_signed(p,number,format,value) ((void)0)
370 # define png_formatted_warning(pp,p,message) ((void)(pp))
371 # define PNG_WARNING_PARAMETERS(p)
372 #endif
373 #ifndef PNG_ERROR_TEXT_SUPPORTED
374 # define png_fixed_error(s1,s2) png_err(s1)
375 #endif
376
377 /* C allows up-casts from (void*) to any pointer and (const void*) to any
378 * pointer to a const object. C++ regards this as a type error and requires an
379 * explicit, static, cast and provides the static_cast<> rune to ensure that
380 * const is not cast away.
381 */
382 #ifdef __cplusplus
383 # define png_voidcast(type, value) static_cast<type>(value)
384 # define png_constcast(type, value) const_cast<type>(value)
385 # define png_aligncast(type, value) \
386 static_cast<type>(static_cast<void*>(value))
387 # define png_aligncastconst(type, value) \
388 static_cast<type>(static_cast<const void*>(value))
389 #else
390 # define png_voidcast(type, value) (value)
391 # define png_constcast(type, value) ((type)(value))
392 # define png_aligncast(type, value) ((void*)(value))
393 # define png_aligncastconst(type, value) ((const void*)(value))
394 #endif /* __cplusplus */
395
396 /* Some fixed point APIs are still required even if not exported because
397 * they get used by the corresponding floating point APIs. This magic
398 * deals with this:
399 */
400 #ifdef PNG_FIXED_POINT_SUPPORTED
401 # define PNGFAPI PNGAPI
402 #else
403 # define PNGFAPI /* PRIVATE */
404 #endif
405
406 #ifndef PNG_VERSION_INFO_ONLY
407 /* Other defines specific to compilers can go here. Try to keep
408 * them inside an appropriate ifdef/endif pair for portability.
409 */
410 #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
411 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
412 /* png.c requires the following ANSI-C constants if the conversion of
413 * floating point to ASCII is implemented therein:
414 *
415 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
416 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
417 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
418 */
419 # include <float.h>
420
421 # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
422 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
423 /* We need to check that <math.h> hasn't already been included earlier
424 * as it seems it doesn't agree with <fp.h>, yet we should really use
425 * <fp.h> if possible.
426 */
427 # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
428 # include <fp.h>
429 # endif
430 # else
431 # include <math.h>
432 # endif
433 # if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
434 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
435 * MATH=68881
436 */
437 # include <m68881.h>
438 # endif
439 #endif
440
441 /* This provides the non-ANSI (far) memory allocation routines. */
442 #if defined(__TURBOC__) && defined(__MSDOS__)
443 # include <mem.h>
444 # include <alloc.h>
445 #endif
446
447 #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
448 defined(_WIN32) || defined(__WIN32__)
449 # define WIN32_NO_STATUS
450 # define WIN32_LEAN_AND_MEAN
451 # include <windows.h> /* defines _WINDOWS_ macro */
452 #endif
453 #endif /* PNG_VERSION_INFO_ONLY */
454
455 /* Moved here around 1.5.0beta36 from pngconf.h */
456 /* Users may want to use these so they are not private. Any library
457 * functions that are passed far data must be model-independent.
458 */
459
460 /* Memory model/platform independent fns */
461 #ifndef PNG_ABORT
462 # ifdef _WINDOWS_
463 # define PNG_ABORT() ExitProcess(0)
464 # else
465 # define PNG_ABORT() abort()
466 # endif
467 #endif
468
469 /* These macros may need to be architecture dependent. */
470 #define PNG_ALIGN_NONE 0 /* do not use data alignment */
471 #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
472 #ifdef offsetof
473 # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
474 #else
475 # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
476 #endif
477 #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
478
479 #ifndef PNG_ALIGN_TYPE
480 /* Default to using aligned access optimizations and requiring alignment to a
481 * multiple of the data type size. Override in a compiler specific fashion
482 * if necessary by inserting tests here:
483 */
484 # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
485 #endif
486
487 #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
488 /* This is used because in some compiler implementations non-aligned
489 * structure members are supported, so the offsetof approach below fails.
490 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
491 * is good for performance. Do not do this unless you have tested the result
492 * and understand it.
493 */
494 # define png_alignof(type) (sizeof (type))
495 #else
496 # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
497 # define png_alignof(type) offsetof(struct{char c; type t;}, t)
498 # else
499 # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
500 # define png_alignof(type) (1)
501 # endif
502 /* Else leave png_alignof undefined to prevent use thereof */
503 # endif
504 #endif
505
506 /* This implicitly assumes alignment is always to a power of 2. */
507 #ifdef png_alignof
508 # define png_isaligned(ptr, type)\
509 ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
510 #else
511 # define png_isaligned(ptr, type) 0
512 #endif
513
514 /* End of memory model/platform independent support */
515 /* End of 1.5.0beta36 move from pngconf.h */
516
517 /* CONSTANTS and UTILITY MACROS
518 * These are used internally by libpng and not exposed in the API
519 */
520
521 /* Various modes of operation. Note that after an init, mode is set to
522 * zero automatically when the structure is created. Three of these
523 * are defined in png.h because they need to be visible to applications
524 * that call png_set_unknown_chunk().
525 */
526 /* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
527 /* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
528 #define PNG_HAVE_IDAT 0x04
529 /* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
530 #define PNG_HAVE_IEND 0x10
531 /* 0x20 (unused) */
532 /* 0x40 (unused) */
533 /* 0x80 (unused) */
534 #define PNG_HAVE_CHUNK_HEADER 0x100
535 #define PNG_WROTE_tIME 0x200
536 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
537 #define PNG_BACKGROUND_IS_GRAY 0x800
538 #define PNG_HAVE_PNG_SIGNATURE 0x1000
539 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
540 /* 0x4000 (unused) */
541 #define PNG_IS_READ_STRUCT 0x8000 /* Else is a write struct */
542
543 /* Flags for the transformations the PNG library does on the image data */
544 #define PNG_BGR 0x0001
545 #define PNG_INTERLACE 0x0002
546 #define PNG_PACK 0x0004
547 #define PNG_SHIFT 0x0008
548 #define PNG_SWAP_BYTES 0x0010
549 #define PNG_INVERT_MONO 0x0020
550 #define PNG_QUANTIZE 0x0040
551 #define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
552 #define PNG_BACKGROUND_EXPAND 0x0100
553 #define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
554 #define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
555 #define PNG_RGBA 0x0800
556 #define PNG_EXPAND 0x1000
557 #define PNG_GAMMA 0x2000
558 #define PNG_GRAY_TO_RGB 0x4000
559 #define PNG_FILLER 0x8000
560 #define PNG_PACKSWAP 0x10000
561 #define PNG_SWAP_ALPHA 0x20000
562 #define PNG_STRIP_ALPHA 0x40000
563 #define PNG_INVERT_ALPHA 0x80000
564 #define PNG_USER_TRANSFORM 0x100000
565 #define PNG_RGB_TO_GRAY_ERR 0x200000
566 #define PNG_RGB_TO_GRAY_WARN 0x400000
567 #define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
568 #define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
569 #define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
570 #define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
571 #define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
572 /* 0x8000000 unused */
573 /* 0x10000000 unused */
574 /* 0x20000000 unused */
575 /* 0x40000000 unused */
576 /* Flags for png_create_struct */
577 #define PNG_STRUCT_PNG 0x0001
578 #define PNG_STRUCT_INFO 0x0002
579
580 /* Flags for the png_ptr->flags rather than declaring a byte for each one */
581 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
582 #define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002 /* Added to libpng-1.6.0 */
583 /* 0x0004 unused */
584 #define PNG_FLAG_ZSTREAM_ENDED 0x0008 /* Added to libpng-1.6.0 */
585 /* 0x0010 unused */
586 /* 0x0020 unused */
587 #define PNG_FLAG_ROW_INIT 0x0040
588 #define PNG_FLAG_FILLER_AFTER 0x0080
589 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
590 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
591 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
592 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
593 #define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
594 #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
595 #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
596 /* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000 */
597 /* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000 */
598 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000
599 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
600 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
601 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000 /* Added to libpng-1.4.0 */
602 #define PNG_FLAG_APP_WARNINGS_WARN 0x200000 /* Added to libpng-1.6.0 */
603 #define PNG_FLAG_APP_ERRORS_WARN 0x400000 /* Added to libpng-1.6.0 */
604 /* 0x800000 unused */
605 /* 0x1000000 unused */
606 /* 0x2000000 unused */
607 /* 0x4000000 unused */
608 /* 0x8000000 unused */
609 /* 0x10000000 unused */
610 /* 0x20000000 unused */
611 /* 0x40000000 unused */
612
613 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
614 PNG_FLAG_CRC_ANCILLARY_NOWARN)
615
616 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
617 PNG_FLAG_CRC_CRITICAL_IGNORE)
618
619 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
620 PNG_FLAG_CRC_CRITICAL_MASK)
621
622 /* Save typing and make code easier to understand */
623
624 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
625 abs((int)((c1).green) - (int)((c2).green)) + \
626 abs((int)((c1).blue) - (int)((c2).blue)))
627
628 /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
629 * by dividing by 257 *with rounding*. This macro is exact for the given range.
630 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the
631 * macro were established by experiment (modifying the added value). The macro
632 * has a second variant that takes a value already scaled by 255 and divides by
633 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it
634 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
635 */
636 #define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
637 #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
638
639 /* Added to libpng-1.2.6 JB */
640 #define PNG_ROWBYTES(pixel_bits, width) \
641 ((pixel_bits) >= 8 ? \
642 ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
643 (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
644
645 /* PNG_OUT_OF_RANGE returns true if value is outside the range
646 * ideal-delta..ideal+delta. Each argument is evaluated twice.
647 * "ideal" and "delta" should be constants, normally simple
648 * integers, "value" a variable. Added to libpng-1.2.6 JB
649 */
650 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
651 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
652
653 /* Conversions between fixed and floating point, only defined if
654 * required (to make sure the code doesn't accidentally use float
655 * when it is supposedly disabled.)
656 */
657 #ifdef PNG_FLOATING_POINT_SUPPORTED
658 /* The floating point conversion can't overflow, though it can and
659 * does lose accuracy relative to the original fixed point value.
660 * In practice this doesn't matter because png_fixed_point only
661 * stores numbers with very low precision. The png_ptr and s
662 * arguments are unused by default but are there in case error
663 * checking becomes a requirement.
664 */
665 #define png_float(png_ptr, fixed, s) (.00001 * (fixed))
666
667 /* The fixed point conversion performs range checking and evaluates
668 * its argument multiple times, so must be used with care. The
669 * range checking uses the PNG specification values for a signed
670 * 32-bit fixed point value except that the values are deliberately
671 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
672 * (2^31-1) * 100000). 's' is a string that describes the value being
673 * converted.
674 *
675 * NOTE: this macro will raise a png_error if the range check fails,
676 * therefore it is normally only appropriate to use this on values
677 * that come from API calls or other sources where an out of range
678 * error indicates a programming error, not a data error!
679 *
680 * NOTE: by default this is off - the macro is not used - because the
681 * function call saves a lot of code.
682 */
683 #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
684 #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
685 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
686 #endif
687 /* else the corresponding function is defined below, inside the scope of the
688 * cplusplus test.
689 */
690 #endif
691
692 /* Constants for known chunk types. If you need to add a chunk, define the name
693 * here. For historical reasons these constants have the form png_<name>; i.e.
694 * the prefix is lower case. Please use decimal values as the parameters to
695 * match the ISO PNG specification and to avoid relying on the C locale
696 * interpretation of character values.
697 *
698 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
699 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
700 * to be generated if required.
701 *
702 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
703 * architectures where (int) is only 16 bits.
704 */
705 #define PNG_32b(b,s) ((png_uint_32)(b) << (s))
706 #define PNG_U32(b1,b2,b3,b4) \
707 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
708
709 /* Constants for known chunk types.
710 *
711 * MAINTAINERS: If you need to add a chunk, define the name here.
712 * For historical reasons these constants have the form png_<name>; i.e.
713 * the prefix is lower case. Please use decimal values as the parameters to
714 * match the ISO PNG specification and to avoid relying on the C locale
715 * interpretation of character values. Please keep the list sorted.
716 *
717 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
718 * type. In fact the specification does not express chunk types this way,
719 * however using a 32-bit value means that the chunk type can be read from the
720 * stream using exactly the same code as used for a 32-bit unsigned value and
721 * can be examined far more efficiently (using one arithmetic compare).
722 *
723 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The
724 * libpng API still uses strings for 'unknown' chunks and a macro,
725 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice
726 * that for portable code numeric values must still be used; the string "IHDR"
727 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
728 *
729 * In 1.7.0 the definitions will be made public in png.h to avoid having to
730 * duplicate the same definitions in application code.
731 */
732 #define png_IDAT PNG_U32( 73, 68, 65, 84)
733 #define png_IEND PNG_U32( 73, 69, 78, 68)
734 #define png_IHDR PNG_U32( 73, 72, 68, 82)
735 #define png_PLTE PNG_U32( 80, 76, 84, 69)
736 #define png_bKGD PNG_U32( 98, 75, 71, 68)
737 #define png_cHRM PNG_U32( 99, 72, 82, 77)
738 #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
739 #define png_gAMA PNG_U32(103, 65, 77, 65)
740 #define png_gIFg PNG_U32(103, 73, 70, 103)
741 #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
742 #define png_gIFx PNG_U32(103, 73, 70, 120)
743 #define png_hIST PNG_U32(104, 73, 83, 84)
744 #define png_iCCP PNG_U32(105, 67, 67, 80)
745 #define png_iTXt PNG_U32(105, 84, 88, 116)
746 #define png_oFFs PNG_U32(111, 70, 70, 115)
747 #define png_pCAL PNG_U32(112, 67, 65, 76)
748 #define png_pHYs PNG_U32(112, 72, 89, 115)
749 #define png_sBIT PNG_U32(115, 66, 73, 84)
750 #define png_sCAL PNG_U32(115, 67, 65, 76)
751 #define png_sPLT PNG_U32(115, 80, 76, 84)
752 #define png_sRGB PNG_U32(115, 82, 71, 66)
753 #define png_sTER PNG_U32(115, 84, 69, 82)
754 #define png_tEXt PNG_U32(116, 69, 88, 116)
755 #define png_tIME PNG_U32(116, 73, 77, 69)
756 #define png_tRNS PNG_U32(116, 82, 78, 83)
757 #define png_zTXt PNG_U32(122, 84, 88, 116)
758
759 /* The following will work on (signed char*) strings, whereas the get_uint_32
760 * macro will fail on top-bit-set values because of the sign extension.
761 */
762 #define PNG_CHUNK_FROM_STRING(s)\
763 PNG_U32(0xff & (s)[0], 0xff & (s)[1], 0xff & (s)[2], 0xff & (s)[3])
764
765 /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
766 * signed and the argument is a (char[]) This macro will fail miserably on
767 * systems where (char) is more than 8 bits.
768 */
769 #define PNG_STRING_FROM_CHUNK(s,c)\
770 (void)(((char*)(s))[0]=(char)(((c)>>24) & 0xff), \
771 ((char*)(s))[1]=(char)(((c)>>16) & 0xff),\
772 ((char*)(s))[2]=(char)(((c)>>8) & 0xff), \
773 ((char*)(s))[3]=(char)((c & 0xff)))
774
775 /* Do the same but terminate with a null character. */
776 #define PNG_CSTRING_FROM_CHUNK(s,c)\
777 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
778
779 /* Test on flag values as defined in the spec (section 5.4): */
780 #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
781 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
782 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
783 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
784 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
785
786 /* Gamma values (new at libpng-1.5.4): */
787 #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
788 #define PNG_GAMMA_MAC_INVERSE 65909
789 #define PNG_GAMMA_sRGB_INVERSE 45455
790
791 /* Almost everything below is C specific; the #defines above can be used in
792 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
793 */
794 #ifndef PNG_VERSION_INFO_ONLY
795
796 #include "pngstruct.h"
797 #include "pnginfo.h"
798
799 /* Validate the include paths - the include path used to generate pnglibconf.h
800 * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
801 */
802 #if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
803 # error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
804 "-I (include path) error: see the notes in pngpriv.h"
805 /* This means that when pnglibconf.h was built the copy of zlib.h that it
806 * used is not the same as the one being used here. Because the build of
807 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
808 * zlib version number and because this affects handling of certain broken
809 * PNG files the -I directives must match.
810 *
811 * The most likely explanation is that you passed a -I in CFLAGS. This will
812 * not work; all the preprocessor directories and in particular all the -I
813 * directives must be in CPPFLAGS.
814 */
815 #endif
816
817 /* This is used for 16-bit gamma tables -- only the top level pointers are
818 * const; this could be changed:
819 */
820 typedef const png_uint_16p * png_const_uint_16pp;
821
822 /* Added to libpng-1.5.7: sRGB conversion tables */
823 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
824 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
825 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED
826 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
827 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
828 * 0..65535. This table gives the closest 16-bit answers (no errors).
829 */
830 #endif
831
832 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
833 PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
834
835 #define PNG_sRGB_FROM_LINEAR(linear) \
836 ((png_byte)(0xff & ((png_sRGB_base[(linear)>>15] \
837 + ((((linear) & 0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8)))
838 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
839 * encoded value with maximum error 0.646365. Note that the input is not a
840 * 16-bit value; it has been multiplied by 255! */
841 #endif /* SIMPLIFIED_READ/WRITE */
842
843
844 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
845 #ifdef __cplusplus
846 extern "C" {
847 #endif /* __cplusplus */
848
849 /* Internal functions; these are not exported from a DLL however because they
850 * are used within several of the C source files they have to be C extern.
851 *
852 * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
853 */
854
855 /* Zlib support */
856 #define PNG_UNEXPECTED_ZLIB_RETURN (-7)
857 PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
858 PNG_EMPTY);
859 /* Used by the zlib handling functions to ensure that z_stream::msg is always
860 * set before they return.
861 */
862
863 #ifdef PNG_WRITE_SUPPORTED
864 PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
865 png_compression_bufferp *list),PNG_EMPTY);
866 /* Free the buffer list used by the compressed write code. */
867 #endif
868
869 #if defined(PNG_FLOATING_POINT_SUPPORTED) && \
870 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
871 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
872 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
873 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
874 (defined(PNG_sCAL_SUPPORTED) && \
875 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
876 PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
877 double fp, png_const_charp text),PNG_EMPTY);
878 #endif
879
880 /* Check the user version string for compatibility, returns false if the version
881 * numbers aren't compatible.
882 */
883 PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
884 png_const_charp user_png_ver),PNG_EMPTY);
885
886 /* Internal base allocator - no messages, NULL on failure to allocate. This
887 * does, however, call the application provided allocator and that could call
888 * png_error (although that would be a bug in the application implementation.)
889 */
890 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
891 png_alloc_size_t size),PNG_ALLOCATED);
892
893 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
894 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
895 /* Internal array allocator, outputs no error or warning messages on failure,
896 * just returns NULL.
897 */
898 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
899 int nelements, size_t element_size),PNG_ALLOCATED);
900
901 /* The same but an existing array is extended by add_elements. This function
902 * also memsets the new elements to 0 and copies the old elements. The old
903 * array is not freed or altered.
904 */
905 PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
906 png_const_voidp array, int old_elements, int add_elements,
907 size_t element_size),PNG_ALLOCATED);
908 #endif /* text, sPLT or unknown chunks */
909
910 /* Magic to create a struct when there is no struct to call the user supplied
911 * memory allocators. Because error handling has not been set up the memory
912 * handlers can't safely call png_error, but this is an obscure and undocumented
913 * restriction so libpng has to assume that the 'free' handler, at least, might
914 * call png_error.
915 */
916 PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
917 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
918 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
919 png_free_ptr free_fn),PNG_ALLOCATED);
920
921 /* Free memory from internal libpng struct */
922 PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
923 PNG_EMPTY);
924
925 /* Free an allocated jmp_buf (always succeeds) */
926 PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
927
928 /* Function to allocate memory for zlib. PNGAPI is disallowed. */
929 PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
930 PNG_ALLOCATED);
931
932 /* Function to free memory for zlib. PNGAPI is disallowed. */
933 PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
934
935 /* Next four functions are used internally as callbacks. PNGCBAPI is required
936 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
937 * PNGCBAPI at 1.5.0
938 */
939
940 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
941 png_bytep data, png_size_t length),PNG_EMPTY);
942
943 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
944 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
945 png_bytep buffer, png_size_t length),PNG_EMPTY);
946 #endif
947
948 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
949 png_bytep data, png_size_t length),PNG_EMPTY);
950
951 #ifdef PNG_WRITE_FLUSH_SUPPORTED
952 # ifdef PNG_STDIO_SUPPORTED
953 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
954 PNG_EMPTY);
955 # endif
956 #endif
957
958 /* Reset the CRC variable */
959 PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
960
961 /* Write the "data" buffer to whatever output you are using */
962 PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
963 png_const_bytep data, png_size_t length),PNG_EMPTY);
964
965 /* Read and check the PNG file signature */
966 PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
967 png_inforp info_ptr),PNG_EMPTY);
968
969 /* Read the chunk header (length + type name) */
970 PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
971 PNG_EMPTY);
972
973 /* Read data from whatever input you are using into the "data" buffer */
974 PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
975 png_size_t length),PNG_EMPTY);
976
977 /* Read bytes into buf, and update png_ptr->crc */
978 PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
979 png_uint_32 length),PNG_EMPTY);
980
981 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
982 PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
983 png_uint_32 skip),PNG_EMPTY);
984
985 /* Read the CRC from the file and compare it to the libpng calculated CRC */
986 PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
987
988 /* Calculate the CRC over a section of data. Note that we are only
989 * passing a maximum of 64K on systems that have this as a memory limit,
990 * since this is the maximum buffer size we can specify.
991 */
992 PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
993 png_const_bytep ptr, png_size_t length),PNG_EMPTY);
994
995 #ifdef PNG_WRITE_FLUSH_SUPPORTED
996 PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
997 #endif
998
999 /* Write various chunks */
1000
1001 /* Write the IHDR chunk, and update the png_struct with the necessary
1002 * information.
1003 */
1004 PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
1005 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
1006 int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
1007
1008 PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
1009 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
1010
1011 PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
1012 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
1013 PNG_EMPTY);
1014
1015 PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
1016
1017 #ifdef PNG_WRITE_gAMA_SUPPORTED
1018 PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
1019 png_fixed_point file_gamma),PNG_EMPTY);
1020 #endif
1021
1022 #ifdef PNG_WRITE_sBIT_SUPPORTED
1023 PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
1024 png_const_color_8p sbit, int color_type),PNG_EMPTY);
1025 #endif
1026
1027 #ifdef PNG_WRITE_cHRM_SUPPORTED
1028 PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
1029 const png_xy *xy), PNG_EMPTY);
1030 /* The xy value must have been previously validated */
1031 #endif
1032
1033 #ifdef PNG_WRITE_sRGB_SUPPORTED
1034 PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
1035 int intent),PNG_EMPTY);
1036 #endif
1037
1038 #ifdef PNG_WRITE_iCCP_SUPPORTED
1039 PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
1040 png_const_charp name, png_const_bytep profile), PNG_EMPTY);
1041 /* The profile must have been previously validated for correctness, the
1042 * length comes from the first four bytes. Only the base, deflate,
1043 * compression is supported.
1044 */
1045 #endif
1046
1047 #ifdef PNG_WRITE_sPLT_SUPPORTED
1048 PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
1049 png_const_sPLT_tp palette),PNG_EMPTY);
1050 #endif
1051
1052 #ifdef PNG_WRITE_tRNS_SUPPORTED
1053 PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
1054 png_const_bytep trans, png_const_color_16p values, int number,
1055 int color_type),PNG_EMPTY);
1056 #endif
1057
1058 #ifdef PNG_WRITE_bKGD_SUPPORTED
1059 PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
1060 png_const_color_16p values, int color_type),PNG_EMPTY);
1061 #endif
1062
1063 #ifdef PNG_WRITE_hIST_SUPPORTED
1064 PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
1065 png_const_uint_16p hist, int num_hist),PNG_EMPTY);
1066 #endif
1067
1068 /* Chunks that have keywords */
1069 #ifdef PNG_WRITE_tEXt_SUPPORTED
1070 PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
1071 png_const_charp key, png_const_charp text, png_size_t text_len),PNG_EMPTY);
1072 #endif
1073
1074 #ifdef PNG_WRITE_zTXt_SUPPORTED
1075 PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
1076 key, png_const_charp text, int compression),PNG_EMPTY);
1077 #endif
1078
1079 #ifdef PNG_WRITE_iTXt_SUPPORTED
1080 PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
1081 int compression, png_const_charp key, png_const_charp lang,
1082 png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
1083 #endif
1084
1085 #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
1086 PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
1087 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
1088 #endif
1089
1090 #ifdef PNG_WRITE_oFFs_SUPPORTED
1091 PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
1092 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
1093 #endif
1094
1095 #ifdef PNG_WRITE_pCAL_SUPPORTED
1096 PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
1097 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
1098 png_const_charp units, png_charpp params),PNG_EMPTY);
1099 #endif
1100
1101 #ifdef PNG_WRITE_pHYs_SUPPORTED
1102 PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
1103 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
1104 int unit_type),PNG_EMPTY);
1105 #endif
1106
1107 #ifdef PNG_WRITE_tIME_SUPPORTED
1108 PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
1109 png_const_timep mod_time),PNG_EMPTY);
1110 #endif
1111
1112 #ifdef PNG_WRITE_sCAL_SUPPORTED
1113 PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
1114 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
1115 #endif
1116
1117 /* Called when finished processing a row of data */
1118 PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
1119 PNG_EMPTY);
1120
1121 /* Internal use only. Called before first row of data */
1122 PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
1123 PNG_EMPTY);
1124
1125 /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
1126 * array of png_ptr->width pixels. If the image is not interlaced or this
1127 * is the final pass this just does a memcpy, otherwise the "display" flag
1128 * is used to determine whether to copy pixels that are not in the current pass.
1129 *
1130 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
1131 * function to achieve the documented 'blocky' appearance during interlaced read
1132 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
1133 * are not changed if they are not in the current pass, when display is 0.
1134 *
1135 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
1136 *
1137 * The API always reads from the png_struct row buffer and always assumes that
1138 * it is full width (png_do_read_interlace has already been called.)
1139 *
1140 * This function is only ever used to write to row buffers provided by the
1141 * caller of the relevant libpng API and the row must have already been
1142 * transformed by the read transformations.
1143 *
1144 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
1145 * bitmasks for use within the code, otherwise runtime generated masks are used.
1146 * The default is compile time masks.
1147 */
1148 #ifndef PNG_USE_COMPILE_TIME_MASKS
1149 # define PNG_USE_COMPILE_TIME_MASKS 1
1150 #endif
1151 PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
1152 png_bytep row, int display),PNG_EMPTY);
1153
1154 #ifdef PNG_READ_INTERLACING_SUPPORTED
1155 /* Expand an interlaced row: the 'row_info' describes the pass data that has
1156 * been read in and must correspond to the pixels in 'row', the pixels are
1157 * expanded (moved apart) in 'row' to match the final layout, when doing this
1158 * the pixels are *replicated* to the intervening space. This is essential for
1159 * the correct operation of png_combine_row, above.
1160 */
1161 PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
1162 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
1163 #endif
1164
1165 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
1166
1167 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
1168 /* Grab pixels out of a row for an interlaced pass */
1169 PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
1170 png_bytep row, int pass),PNG_EMPTY);
1171 #endif
1172
1173 /* Unfilter a row: check the filter value before calling this, there is no point
1174 * calling it for PNG_FILTER_VALUE_NONE.
1175 */
1176 PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
1177 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
1178
1179 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
1180 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1181 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
1182 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1183 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
1184 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1185 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
1186 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1187 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
1188 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1189 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
1190 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1191 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
1192 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1193
1194 /* Choose the best filter to use and filter the row data */
1195 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
1196 png_row_infop row_info),PNG_EMPTY);
1197
1198 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1199 PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
1200 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
1201 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer
1202 * is NULL the function checks, instead, for the end of the stream. In this
1203 * case a benign error will be issued if the stream end is not found or if
1204 * extra data has to be consumed.
1205 */
1206 PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
1207 PNG_EMPTY);
1208 /* This cleans up when the IDAT LZ stream does not end when the last image
1209 * byte is read; there is still some pending input.
1210 */
1211
1212 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
1213 PNG_EMPTY);
1214 /* Finish a row while reading, dealing with interlacing passes, etc. */
1215 #endif /* SEQUENTIAL_READ */
1216
1217 /* Initialize the row buffers, etc. */
1218 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
1219
1220 #if PNG_ZLIB_VERNUM >= 0x1240
1221 PNG_INTERNAL_FUNCTION(int,png_zlib_inflate,(png_structrp png_ptr, int flush),
1222 PNG_EMPTY);
1223 # define PNG_INFLATE(pp, flush) png_zlib_inflate(pp, flush)
1224 #else /* Zlib < 1.2.4 */
1225 # define PNG_INFLATE(pp, flush) inflate(&(pp)->zstream, flush)
1226 #endif /* Zlib < 1.2.4 */
1227
1228 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1229 /* Optional call to update the users info structure */
1230 PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
1231 png_inforp info_ptr),PNG_EMPTY);
1232 #endif
1233
1234 /* Shared transform functions, defined in pngtran.c */
1235 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1236 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1237 PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
1238 png_bytep row, int at_start),PNG_EMPTY);
1239 #endif
1240
1241 #ifdef PNG_16BIT_SUPPORTED
1242 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1243 PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
1244 png_bytep row),PNG_EMPTY);
1245 #endif
1246 #endif
1247
1248 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1249 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1250 PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
1251 png_bytep row),PNG_EMPTY);
1252 #endif
1253
1254 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1255 PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
1256 png_bytep row),PNG_EMPTY);
1257 #endif
1258
1259 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1260 PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
1261 png_bytep row),PNG_EMPTY);
1262 #endif
1263
1264 /* The following decodes the appropriate chunks, and does error correction,
1265 * then calls the appropriate callback for the chunk if it is valid.
1266 */
1267
1268 /* Decode the IHDR chunk */
1269 PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
1270 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1271 PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
1272 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1273 PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
1274 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1275
1276 #ifdef PNG_READ_bKGD_SUPPORTED
1277 PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
1278 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1279 #endif
1280
1281 #ifdef PNG_READ_cHRM_SUPPORTED
1282 PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
1283 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1284 #endif
1285
1286 #ifdef PNG_READ_gAMA_SUPPORTED
1287 PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
1288 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1289 #endif
1290
1291 #ifdef PNG_READ_hIST_SUPPORTED
1292 PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
1293 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1294 #endif
1295
1296 #ifdef PNG_READ_iCCP_SUPPORTED
1297 PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
1298 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1299 #endif /* READ_iCCP */
1300
1301 #ifdef PNG_READ_iTXt_SUPPORTED
1302 PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
1303 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1304 #endif
1305
1306 #ifdef PNG_READ_oFFs_SUPPORTED
1307 PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
1308 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1309 #endif
1310
1311 #ifdef PNG_READ_pCAL_SUPPORTED
1312 PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
1313 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1314 #endif
1315
1316 #ifdef PNG_READ_pHYs_SUPPORTED
1317 PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
1318 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1319 #endif
1320
1321 #ifdef PNG_READ_sBIT_SUPPORTED
1322 PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
1323 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1324 #endif
1325
1326 #ifdef PNG_READ_sCAL_SUPPORTED
1327 PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
1328 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1329 #endif
1330
1331 #ifdef PNG_READ_sPLT_SUPPORTED
1332 PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
1333 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1334 #endif /* READ_sPLT */
1335
1336 #ifdef PNG_READ_sRGB_SUPPORTED
1337 PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
1338 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1339 #endif
1340
1341 #ifdef PNG_READ_tEXt_SUPPORTED
1342 PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
1343 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1344 #endif
1345
1346 #ifdef PNG_READ_tIME_SUPPORTED
1347 PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
1348 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1349 #endif
1350
1351 #ifdef PNG_READ_tRNS_SUPPORTED
1352 PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
1353 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1354 #endif
1355
1356 #ifdef PNG_READ_zTXt_SUPPORTED
1357 PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
1358 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1359 #endif
1360
1361 PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr,
1362 png_uint_32 chunk_name),PNG_EMPTY);
1363
1364 PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
1365 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
1366 /* This is the function that gets called for unknown chunks. The 'keep'
1367 * argument is either non-zero for a known chunk that has been set to be
1368 * handled as unknown or zero for an unknown chunk. By default the function
1369 * just skips the chunk or errors out if it is critical.
1370 */
1371
1372 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\
1373 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED)
1374 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
1375 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
1376 /* Exactly as the API png_handle_as_unknown() except that the argument is a
1377 * 32-bit chunk name, not a string.
1378 */
1379 #endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */
1380
1381 /* Handle the transformations for reading and writing */
1382 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1383 PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
1384 png_row_infop row_info),PNG_EMPTY);
1385 #endif
1386 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1387 PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
1388 png_row_infop row_info),PNG_EMPTY);
1389 #endif
1390
1391 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1392 PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
1393 PNG_EMPTY);
1394 #endif
1395
1396 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1397 PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
1398 png_inforp info_ptr),PNG_EMPTY);
1399 PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
1400 png_inforp info_ptr),PNG_EMPTY);
1401 PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
1402 PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
1403 PNG_EMPTY);
1404 PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
1405 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
1406 PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
1407 PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
1408 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
1409 PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
1410 PNG_EMPTY);
1411 PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
1412 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1413 PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
1414 png_inforp info_ptr),PNG_EMPTY);
1415 PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
1416 png_inforp info_ptr),PNG_EMPTY);
1417 PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
1418 png_bytep row),PNG_EMPTY);
1419 PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
1420 png_inforp info_ptr),PNG_EMPTY);
1421 PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
1422 png_inforp info_ptr),PNG_EMPTY);
1423 PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
1424 PNG_EMPTY);
1425 # ifdef PNG_READ_tEXt_SUPPORTED
1426 PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
1427 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1428 PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
1429 png_inforp info_ptr),PNG_EMPTY);
1430 # endif
1431 # ifdef PNG_READ_zTXt_SUPPORTED
1432 PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
1433 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1434 PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
1435 png_inforp info_ptr),PNG_EMPTY);
1436 # endif
1437 # ifdef PNG_READ_iTXt_SUPPORTED
1438 PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
1439 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1440 PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
1441 png_inforp info_ptr),PNG_EMPTY);
1442 # endif
1443
1444 #endif /* PROGRESSIVE_READ */
1445
1446 /* Added at libpng version 1.6.0 */
1447 #ifdef PNG_GAMMA_SUPPORTED
1448 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
1449 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
1450 /* Set the colorspace gamma with a value provided by the application or by
1451 * the gAMA chunk on read. The value will override anything set by an ICC
1452 * profile.
1453 */
1454
1455 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
1456 png_inforp info_ptr), PNG_EMPTY);
1457 /* Synchronize the info 'valid' flags with the colorspace */
1458
1459 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
1460 png_inforp info_ptr), PNG_EMPTY);
1461 /* Copy the png_struct colorspace to the info_struct and call the above to
1462 * synchronize the flags. Checks for NULL info_ptr and does nothing.
1463 */
1464 #endif
1465
1466 /* Added at libpng version 1.4.0 */
1467 #ifdef PNG_COLORSPACE_SUPPORTED
1468 /* These internal functions are for maintaining the colorspace structure within
1469 * a png_info or png_struct (or, indeed, both).
1470 */
1471 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
1472 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
1473 int preferred), PNG_EMPTY);
1474
1475 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
1476 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
1477 int preferred), PNG_EMPTY);
1478
1479 #ifdef PNG_sRGB_SUPPORTED
1480 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
1481 png_colorspacerp colorspace, int intent), PNG_EMPTY);
1482 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
1483 * flags to write them, if it returns false there was a problem and an error
1484 * message has already been output (but the colorspace may still need to be
1485 * synced to record the invalid flag).
1486 */
1487 #endif /* sRGB */
1488
1489 #ifdef PNG_iCCP_SUPPORTED
1490 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
1491 png_colorspacerp colorspace, png_const_charp name,
1492 png_uint_32 profile_length, png_const_bytep profile, int color_type),
1493 PNG_EMPTY);
1494 /* The 'name' is used for information only */
1495
1496 /* Routines for checking parts of an ICC profile. */
1497 PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
1498 png_colorspacerp colorspace, png_const_charp name,
1499 png_uint_32 profile_length), PNG_EMPTY);
1500 PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
1501 png_colorspacerp colorspace, png_const_charp name,
1502 png_uint_32 profile_length,
1503 png_const_bytep profile /* first 132 bytes only */, int color_type),
1504 PNG_EMPTY);
1505 PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
1506 png_colorspacerp colorspace, png_const_charp name,
1507 png_uint_32 profile_length,
1508 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
1509 #ifdef PNG_sRGB_SUPPORTED
1510 PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
1511 png_const_structrp png_ptr, png_colorspacerp colorspace,
1512 png_const_bytep profile, uLong adler), PNG_EMPTY);
1513 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
1514 * be zero to indicate that it is not available. It is used, if provided,
1515 * as a fast check on the profile when checking to see if it is sRGB.
1516 */
1517 #endif
1518 #endif /* iCCP */
1519
1520 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1521 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
1522 (png_structrp png_ptr), PNG_EMPTY);
1523 /* Set the rgb_to_gray coefficients from the colorspace Y values */
1524 #endif /* READ_RGB_TO_GRAY */
1525 #endif /* COLORSPACE */
1526
1527 /* Added at libpng version 1.4.0 */
1528 PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
1529 png_uint_32 width, png_uint_32 height, int bit_depth,
1530 int color_type, int interlace_type, int compression_type,
1531 int filter_type),PNG_EMPTY);
1532
1533 /* Added at libpng version 1.5.10 */
1534 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
1535 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
1536 PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
1537 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
1538 #endif
1539
1540 #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1541 PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
1542 png_const_charp name),PNG_NORETURN);
1543 #endif
1544
1545 /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1546 * the end. Always leaves the buffer nul terminated. Never errors out (and
1547 * there is no error code.)
1548 */
1549 PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
1550 size_t pos, png_const_charp string),PNG_EMPTY);
1551
1552 /* Various internal functions to handle formatted warning messages, currently
1553 * only implemented for warnings.
1554 */
1555 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1556 /* Utility to dump an unsigned value into a buffer, given a start pointer and
1557 * and end pointer (which should point just *beyond* the end of the buffer!)
1558 * Returns the pointer to the start of the formatted string. This utility only
1559 * does unsigned values.
1560 */
1561 PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
1562 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
1563
1564 /* Convenience macro that takes an array: */
1565 #define PNG_FORMAT_NUMBER(buffer,format,number) \
1566 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1567
1568 /* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1569 #define PNG_NUMBER_BUFFER_SIZE 24
1570
1571 /* These are the integer formats currently supported, the name is formed from
1572 * the standard printf(3) format string.
1573 */
1574 #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1575 #define PNG_NUMBER_FORMAT_02u 2
1576 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1577 #define PNG_NUMBER_FORMAT_02d 2
1578 #define PNG_NUMBER_FORMAT_x 3
1579 #define PNG_NUMBER_FORMAT_02x 4
1580 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1581 #endif
1582
1583 #ifdef PNG_WARNINGS_SUPPORTED
1584 /* New defines and members adding in libpng-1.5.4 */
1585 # define PNG_WARNING_PARAMETER_SIZE 32
1586 # define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
1587
1588 /* An l-value of this type has to be passed to the APIs below to cache the
1589 * values of the parameters to a formatted warning message.
1590 */
1591 typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1592 PNG_WARNING_PARAMETER_SIZE];
1593
1594 PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
1595 int number, png_const_charp string),PNG_EMPTY);
1596 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1597 * including the trailing '\0'.
1598 */
1599 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
1600 (png_warning_parameters p, int number, int format, png_alloc_size_t value),
1601 PNG_EMPTY);
1602 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1603 * need to output. Use the following for a signed value.
1604 */
1605 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
1606 (png_warning_parameters p, int number, int format, png_int_32 value),
1607 PNG_EMPTY);
1608
1609 PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
1610 png_warning_parameters p, png_const_charp message),PNG_EMPTY);
1611 /* 'message' follows the X/Open approach of using @1, @2 to insert
1612 * parameters previously supplied using the above functions. Errors in
1613 * specifying the parameters will simply result in garbage substitutions.
1614 */
1615 #endif
1616
1617 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
1618 /* Application errors (new in 1.6); use these functions (declared below) for
1619 * errors in the parameters or order of API function calls on read. The
1620 * 'warning' should be used for an error that can be handled completely; the
1621 * 'error' for one which can be handled safely but which may lose application
1622 * information or settings.
1623 *
1624 * By default these both result in a png_error call prior to release, while in a
1625 * released version the 'warning' is just a warning. However if the application
1626 * explicitly disables benign errors (explicitly permitting the code to lose
1627 * information) they both turn into warnings.
1628 *
1629 * If benign errors aren't supported they end up as the corresponding base call
1630 * (png_warning or png_error.)
1631 */
1632 PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
1633 png_const_charp message),PNG_EMPTY);
1634 /* The application provided invalid parameters to an API function or called
1635 * an API function at the wrong time, libpng can completely recover.
1636 */
1637
1638 PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
1639 png_const_charp message),PNG_EMPTY);
1640 /* As above but libpng will ignore the call, or attempt some other partial
1641 * recovery from the error.
1642 */
1643 #else
1644 # define png_app_warning(pp,s) png_warning(pp,s)
1645 # define png_app_error(pp,s) png_error(pp,s)
1646 #endif
1647
1648 PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
1649 png_const_charp message, int error),PNG_EMPTY);
1650 /* Report a recoverable issue in chunk data. On read this is used to report
1651 * a problem found while reading a particular chunk and the
1652 * png_chunk_benign_error or png_chunk_warning function is used as
1653 * appropriate. On write this is used to report an error that comes from
1654 * data set via an application call to a png_set_ API and png_app_error or
1655 * png_app_warning is used as appropriate.
1656 *
1657 * The 'error' parameter must have one of the following values:
1658 */
1659 #define PNG_CHUNK_WARNING 0 /* never an error */
1660 #define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
1661 #define PNG_CHUNK_ERROR 2 /* always an error */
1662
1663 /* ASCII to FP interfaces, currently only implemented if sCAL
1664 * support is required.
1665 */
1666 #if defined(PNG_sCAL_SUPPORTED)
1667 /* MAX_DIGITS is actually the maximum number of characters in an sCAL
1668 * width or height, derived from the precision (number of significant
1669 * digits - a build time settable option) and assumptions about the
1670 * maximum ridiculous exponent.
1671 */
1672 #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1673
1674 #ifdef PNG_FLOATING_POINT_SUPPORTED
1675 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
1676 png_charp ascii, png_size_t size, double fp, unsigned int precision),
1677 PNG_EMPTY);
1678 #endif /* FLOATING_POINT */
1679
1680 #ifdef PNG_FIXED_POINT_SUPPORTED
1681 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
1682 png_charp ascii, png_size_t size, png_fixed_point fp),PNG_EMPTY);
1683 #endif /* FIXED_POINT */
1684 #endif /* sCAL */
1685
1686 #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1687 /* An internal API to validate the format of a floating point number.
1688 * The result is the index of the next character. If the number is
1689 * not valid it will be the index of a character in the supposed number.
1690 *
1691 * The format of a number is defined in the PNG extensions specification
1692 * and this API is strictly conformant to that spec, not anyone elses!
1693 *
1694 * The format as a regular expression is:
1695 *
1696 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1697 *
1698 * or:
1699 *
1700 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1701 *
1702 * The complexity is that either integer or fraction must be present and the
1703 * fraction is permitted to have no digits only if the integer is present.
1704 *
1705 * NOTE: The dangling E problem.
1706 * There is a PNG valid floating point number in the following:
1707 *
1708 * PNG floating point numbers are not greedy.
1709 *
1710 * Working this out requires *TWO* character lookahead (because of the
1711 * sign), the parser does not do this - it will fail at the 'r' - this
1712 * doesn't matter for PNG sCAL chunk values, but it requires more care
1713 * if the value were ever to be embedded in something more complex. Use
1714 * ANSI-C strtod if you need the lookahead.
1715 */
1716 /* State table for the parser. */
1717 #define PNG_FP_INTEGER 0 /* before or in integer */
1718 #define PNG_FP_FRACTION 1 /* before or in fraction */
1719 #define PNG_FP_EXPONENT 2 /* before or in exponent */
1720 #define PNG_FP_STATE 3 /* mask for the above */
1721 #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1722 #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1723 #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1724 #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1725 #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1726
1727 /* These three values don't affect the parser. They are set but not used.
1728 */
1729 #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1730 #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1731 #define PNG_FP_NONZERO 256 /* A non-zero value */
1732 #define PNG_FP_STICKY 448 /* The above three flags */
1733
1734 /* This is available for the caller to store in 'state' if required. Do not
1735 * call the parser after setting it (the parser sometimes clears it.)
1736 */
1737 #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1738
1739 /* Result codes for the parser (boolean - true meants ok, false means
1740 * not ok yet.)
1741 */
1742 #define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1743 #define PNG_FP_OK 1 /* The number is valid */
1744
1745 /* Tests on the sticky non-zero and negative flags. To pass these checks
1746 * the state must also indicate that the whole number is valid - this is
1747 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1748 * is equivalent to PNG_FP_OK above.)
1749 */
1750 #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1751 /* NZ_MASK: the string is valid and a non-zero negative value */
1752 #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
1753 /* Z MASK: the string is valid and a non-zero value. */
1754 /* PNG_FP_SAW_DIGIT: the string is valid. */
1755 #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
1756 #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
1757 #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
1758
1759 /* The actual parser. This can be called repeatedly. It updates
1760 * the index into the string and the state variable (which must
1761 * be initialized to 0). It returns a result code, as above. There
1762 * is no point calling the parser any more if it fails to advance to
1763 * the end of the string - it is stuck on an invalid character (or
1764 * terminated by '\0').
1765 *
1766 * Note that the pointer will consume an E or even an E+ and then leave
1767 * a 'maybe' state even though a preceding integer.fraction is valid.
1768 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
1769 * a valid number. It's possible to recover from this by calling
1770 * the parser again (from the start, with state 0) but with a string
1771 * that omits the last character (i.e. set the size to the index of
1772 * the problem character.) This has not been tested within libpng.
1773 */
1774 PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
1775 png_size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
1776
1777 /* This is the same but it checks a complete string and returns true
1778 * only if it just contains a floating point number. As of 1.5.4 this
1779 * function also returns the state at the end of parsing the number if
1780 * it was valid (otherwise it returns 0.) This can be used for testing
1781 * for negative or zero values using the sticky flag.
1782 */
1783 PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
1784 png_size_t size),PNG_EMPTY);
1785 #endif /* pCAL || sCAL */
1786
1787 #if defined(PNG_GAMMA_SUPPORTED) ||\
1788 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
1789 /* Added at libpng version 1.5.0 */
1790 /* This is a utility to provide a*times/div (rounded) and indicate
1791 * if there is an overflow. The result is a boolean - false (0)
1792 * for overflow, true (1) if no overflow, in which case *res
1793 * holds the result.
1794 */
1795 PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
1796 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
1797 #endif
1798
1799 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
1800 /* Same deal, but issue a warning on overflow and return 0. */
1801 PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
1802 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
1803 png_int_32 divided_by),PNG_EMPTY);
1804 #endif
1805
1806 #ifdef PNG_GAMMA_SUPPORTED
1807 /* Calculate a reciprocal - used for gamma values. This returns
1808 * 0 if the argument is 0 in order to maintain an undefined value;
1809 * there are no warnings.
1810 */
1811 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
1812 PNG_EMPTY);
1813
1814 #ifdef PNG_READ_GAMMA_SUPPORTED
1815 /* The same but gives a reciprocal of the product of two fixed point
1816 * values. Accuracy is suitable for gamma calculations but this is
1817 * not exact - use png_muldiv for that. Only required at present on read.
1818 */
1819 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
1820 png_fixed_point b),PNG_EMPTY);
1821 #endif
1822
1823 /* Return true if the gamma value is significantly different from 1.0 */
1824 PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
1825 PNG_EMPTY);
1826 #endif
1827
1828 #ifdef PNG_READ_GAMMA_SUPPORTED
1829 /* Internal fixed point gamma correction. These APIs are called as
1830 * required to convert single values - they don't need to be fast,
1831 * they are not used when processing image pixel values.
1832 *
1833 * While the input is an 'unsigned' value it must actually be the
1834 * correct bit value - 0..255 or 0..65535 as required.
1835 */
1836 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
1837 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
1838 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
1839 png_fixed_point gamma_value),PNG_EMPTY);
1840 PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
1841 png_fixed_point gamma_value),PNG_EMPTY);
1842 PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
1843 PNG_EMPTY);
1844 PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
1845 int bit_depth),PNG_EMPTY);
1846 #endif
1847
1848 /* SIMPLIFIED READ/WRITE SUPPORT */
1849 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
1850 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
1851 /* The internal structure that png_image::opaque points to. */
1852 typedef struct png_control
1853 {
1854 png_structp png_ptr;
1855 png_infop info_ptr;
1856 png_voidp error_buf; /* Always a jmp_buf at present. */
1857
1858 png_const_bytep memory; /* Memory buffer. */
1859 png_size_t size; /* Size of the memory buffer. */
1860
1861 unsigned int for_write :1; /* Otherwise it is a read structure */
1862 unsigned int owned_file :1; /* We own the file in io_ptr */
1863 } png_control;
1864
1865 /* Return the pointer to the jmp_buf from a png_control: necessary because C
1866 * does not reveal the type of the elements of jmp_buf.
1867 */
1868 #ifdef __cplusplus
1869 # define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
1870 #else
1871 # define png_control_jmp_buf(pc) ((pc)->error_buf)
1872 #endif
1873
1874 /* Utility to safely execute a piece of libpng code catching and logging any
1875 * errors that might occur. Returns true on success, false on failure (either
1876 * of the function or as a result of a png_error.)
1877 */
1878 PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr,
1879 png_const_charp error_message),PNG_NORETURN);
1880
1881 #ifdef PNG_WARNINGS_SUPPORTED
1882 PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr,
1883 png_const_charp warning_message),PNG_EMPTY);
1884 #else
1885 # define png_safe_warning 0/*dummy argument*/
1886 #endif
1887
1888 PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
1889 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
1890
1891 /* Utility to log an error; this also cleans up the png_image; the function
1892 * always returns 0 (false).
1893 */
1894 PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
1895 png_const_charp error_message),PNG_EMPTY);
1896
1897 #ifndef PNG_SIMPLIFIED_READ_SUPPORTED
1898 /* png_image_free is used by the write code but not exported */
1899 PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
1900 #endif /* !SIMPLIFIED_READ */
1901
1902 #endif /* SIMPLIFIED READ/WRITE */
1903
1904 /* These are initialization functions for hardware specific PNG filter
1905 * optimizations; list these here then select the appropriate one at compile
1906 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
1907 * the generic code is used.
1908 */
1909 #ifdef PNG_FILTER_OPTIMIZATIONS
1910 PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
1911 unsigned int bpp), PNG_EMPTY);
1912 /* Just declare the optimization that will be used */
1913 #else
1914 /* List *all* the possible optimizations here - this branch is required if
1915 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
1916 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
1917 */
1918 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
1919 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
1920 #endif
1921
1922 PNG_INTERNAL_FUNCTION(png_uint_32, png_check_keyword, (png_structrp png_ptr,
1923 png_const_charp key, png_bytep new_key), PNG_EMPTY);
1924
1925 /* Maintainer: Put new private prototypes here ^ */
1926
1927 #include "pngdebug.h"
1928
1929 #ifdef __cplusplus
1930 }
1931 #endif
1932
1933 #endif /* PNG_VERSION_INFO_ONLY */
1934 #endif /* PNGPRIV_H */