grub2: bring back build of aros-side grub2 tools
[AROS.git] / workbench / libs / png / pngpriv.h
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2 /* pngpriv.h - private declarations for use inside libpng
4 * For conditions of distribution and use, see copyright notice in png.h
5 * Copyright (c) 1998-2013 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.)
9 * Last changed in libpng 1.6.3 [July 18, 2013]
11 * This code is released under the libpng license.
12 * For conditions of distribution and use, see the disclaimer
13 * and license in png.h
16 /* The symbols declared in this file (including the functions declared
17 * as extern) are PRIVATE. They are not part of the libpng public
18 * interface, and are not recommended for use by regular applications.
19 * Some of them may become public in the future; others may stay private,
20 * change in an incompatible way, or even disappear.
21 * Although the libpng users are not forbidden to include this header,
22 * they should be well aware of the issues that may arise from doing so.
25 #ifndef PNGPRIV_H
26 #define PNGPRIV_H
28 /* Feature Test Macros. The following are defined here to ensure that correctly
29 * implemented libraries reveal the APIs libpng needs to build and hide those
30 * that are not needed and potentially damaging to the compilation.
32 * Feature Test Macros must be defined before any system header is included (see
33 * POSIX 1003.1 2.8.2 "POSIX Symbols."
35 * These macros only have an effect if the operating system supports either
36 * POSIX 1003.1 or C99, or both. On other operating systems (particularly
37 * Windows/Visual Studio) there is no effect; the OS specific tests below are
38 * still required (as of 2011-05-02.)
40 #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */
42 #ifndef PNG_VERSION_INFO_ONLY
43 /* Standard library headers not required by png.h: */
44 # include <stdlib.h>
45 # include <string.h>
46 #endif
48 #define PNGLIB_BUILD /*libpng is being built, not used*/
50 /* If HAVE_CONFIG_H is defined during the build then the build system must
51 * provide an appropriate "config.h" file on the include path. The header file
52 * must provide definitions as required below (search for "HAVE_CONFIG_H");
53 * see configure.ac for more details of the requirements. The macro
54 * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on
55 * 'configure'; define this macro to prevent the configure build including the
56 * configure generated config.h. Libpng is expected to compile without *any*
57 * special build system support on a reasonably ANSI-C compliant system.
59 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H)
60 # include <config.h>
62 /* Pick up the definition of 'restrict' from config.h if it was read: */
63 # define PNG_RESTRICT restrict
64 #endif
66 /* To support symbol prefixing it is necessary to know *before* including png.h
67 * whether the fixed point (and maybe other) APIs are exported, because if they
68 * are not internal definitions may be required. This is handled below just
69 * before png.h is included, but load the configuration now if it is available.
71 #ifndef PNGLCONF_H
72 # include "pnglibconf.h"
73 #endif
75 /* Local renames may change non-exported API functions from png.h */
76 #if defined(PNG_PREFIX) && !defined(PNGPREFIX_H)
77 # include "pngprefix.h"
78 #endif
80 #ifdef PNG_USER_CONFIG
81 # include "pngusr.h"
82 /* These should have been defined in pngusr.h */
83 # ifndef PNG_USER_PRIVATEBUILD
84 # define PNG_USER_PRIVATEBUILD "Custom libpng build"
85 # endif
86 # ifndef PNG_USER_DLLFNAME_POSTFIX
87 # define PNG_USER_DLLFNAME_POSTFIX "Cb"
88 # endif
89 #endif
91 /* Compile time options.
92 * =====================
93 * In a multi-arch build the compiler may compile the code several times for the
94 * same object module, producing different binaries for different architectures.
95 * When this happens configure-time setting of the target host options cannot be
96 * done and this interferes with the handling of the ARM NEON optimizations, and
97 * possibly other similar optimizations. Put additional tests here; in general
98 * this is needed when the same option can be changed at both compile time and
99 * run time depending on the target OS (i.e. iOS vs Android.)
101 * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because
102 * this is not possible with certain compilers (Oracle SUN OS CC), as a result
103 * it is necessary to ensure that all extern functions that *might* be used
104 * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__
105 * below is one example of this behavior because it is controlled by the
106 * presence or not of -mfpu=neon on the GCC command line, it is possible to do
107 * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely
108 * do this.
110 #ifndef PNG_ARM_NEON_OPT
111 /* ARM NEON optimizations are being controlled by the compiler settings,
112 * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon
113 * with GCC) then the compiler will define __ARM_NEON__ and we can rely
114 * unconditionally on NEON instructions not crashing, otherwise we must
115 * disable use of NEON instructions:
117 # ifdef __ARM_NEON__
118 # define PNG_ARM_NEON_OPT 2
119 # else
120 # define PNG_ARM_NEON_OPT 0
121 # endif
122 #endif
124 #if PNG_ARM_NEON_OPT > 0
125 /* NEON optimizations are to be at least considered by libpng, so enable the
126 * callbacks to do this.
128 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon
129 #endif
131 /* Is this a build of a DLL where compilation of the object modules requires
132 * different preprocessor settings to those required for a simple library? If
133 * so PNG_BUILD_DLL must be set.
135 * If libpng is used inside a DLL but that DLL does not export the libpng APIs
136 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a
137 * static library of libpng then link the DLL against that.
139 #ifndef PNG_BUILD_DLL
140 # ifdef DLL_EXPORT
141 /* This is set by libtool when files are compiled for a DLL; libtool
142 * always compiles twice, even on systems where it isn't necessary. Set
143 * PNG_BUILD_DLL in case it is necessary:
145 # define PNG_BUILD_DLL
146 # else
147 # ifdef _WINDLL
148 /* This is set by the Microsoft Visual Studio IDE in projects that
149 * build a DLL. It can't easily be removed from those projects (it
150 * isn't visible in the Visual Studio UI) so it is a fairly reliable
151 * indication that PNG_IMPEXP needs to be set to the DLL export
152 * attributes.
154 # define PNG_BUILD_DLL
155 # else
156 # ifdef __DLL__
157 /* This is set by the Borland C system when compiling for a DLL
158 * (as above.)
160 # define PNG_BUILD_DLL
161 # else
162 /* Add additional compiler cases here. */
163 # endif
164 # endif
165 # endif
166 #endif /* Setting PNG_BUILD_DLL if required */
168 /* See pngconf.h for more details: the builder of the library may set this on
169 * the command line to the right thing for the specific compilation system or it
170 * may be automagically set above (at present we know of no system where it does
171 * need to be set on the command line.)
173 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h
174 * setting it to the "import" setting for a DLL build.
176 #ifndef PNG_IMPEXP
177 # ifdef PNG_BUILD_DLL
178 # define PNG_IMPEXP PNG_DLL_EXPORT
179 # else
180 /* Not building a DLL, or the DLL doesn't require specific export
181 * definitions.
183 # define PNG_IMPEXP
184 # endif
185 #endif
187 /* No warnings for private or deprecated functions in the build: */
188 #ifndef PNG_DEPRECATED
189 # define PNG_DEPRECATED
190 #endif
191 #ifndef PNG_PRIVATE
192 # define PNG_PRIVATE
193 #endif
195 /* Symbol preprocessing support.
197 * To enable listing global, but internal, symbols the following macros should
198 * always be used to declare an extern data or function object in this file.
200 #ifndef PNG_INTERNAL_DATA
201 # define PNG_INTERNAL_DATA(type, name, array) extern type name array
202 #endif
204 #ifndef PNG_INTERNAL_FUNCTION
205 # define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\
206 extern PNG_FUNCTION(type, name, args, PNG_EMPTY attributes)
207 #endif
209 /* If floating or fixed point APIs are disabled they may still be compiled
210 * internally. To handle this make sure they are declared as the appropriate
211 * internal extern function (otherwise the symbol prefixing stuff won't work and
212 * the functions will be used without definitions.)
214 * NOTE: although all the API functions are declared here they are not all
215 * actually built! Because the declarations are still made it is necessary to
216 * fake out types that they depend on.
218 #ifndef PNG_FP_EXPORT
219 # ifndef PNG_FLOATING_POINT_SUPPORTED
220 # define PNG_FP_EXPORT(ordinal, type, name, args)\
221 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
222 # ifndef PNG_VERSION_INFO_ONLY
223 typedef struct png_incomplete png_double;
224 typedef png_double* png_doublep;
225 typedef const png_double* png_const_doublep;
226 typedef png_double** png_doublepp;
227 # endif
228 # endif
229 #endif
230 #ifndef PNG_FIXED_EXPORT
231 # ifndef PNG_FIXED_POINT_SUPPORTED
232 # define PNG_FIXED_EXPORT(ordinal, type, name, args)\
233 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY);
234 # endif
235 #endif
237 #include "png.h"
239 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */
240 #ifndef PNG_DLL_EXPORT
241 # define PNG_DLL_EXPORT
242 #endif
244 /* SECURITY and SAFETY:
246 * By default libpng is built without any internal limits on image size,
247 * individual heap (png_malloc) allocations or the total amount of memory used.
248 * If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used
249 * (unless individually overridden). These limits are believed to be fairly
250 * safe, but builders of secure systems should verify the values against the
251 * real system capabilities.
253 #ifdef PNG_SAFE_LIMITS_SUPPORTED
254 /* 'safe' limits */
255 # ifndef PNG_USER_WIDTH_MAX
256 # define PNG_USER_WIDTH_MAX 1000000
257 # endif
258 # ifndef PNG_USER_HEIGHT_MAX
259 # define PNG_USER_HEIGHT_MAX 1000000
260 # endif
261 # ifndef PNG_USER_CHUNK_CACHE_MAX
262 # define PNG_USER_CHUNK_CACHE_MAX 128
263 # endif
264 # ifndef PNG_USER_CHUNK_MALLOC_MAX
265 # define PNG_USER_CHUNK_MALLOC_MAX 8000000
266 # endif
267 #else
268 /* values for no limits */
269 # ifndef PNG_USER_WIDTH_MAX
270 # define PNG_USER_WIDTH_MAX 0x7fffffff
271 # endif
272 # ifndef PNG_USER_HEIGHT_MAX
273 # define PNG_USER_HEIGHT_MAX 0x7fffffff
274 # endif
275 # ifndef PNG_USER_CHUNK_CACHE_MAX
276 # define PNG_USER_CHUNK_CACHE_MAX 0
277 # endif
278 # ifndef PNG_USER_CHUNK_MALLOC_MAX
279 # define PNG_USER_CHUNK_MALLOC_MAX 0
280 # endif
281 #endif
283 /* Moved to pngpriv.h at libpng-1.5.0 */
284 /* NOTE: some of these may have been used in external applications as
285 * these definitions were exposed in pngconf.h prior to 1.5.
288 /* If you are running on a machine where you cannot allocate more
289 * than 64K of memory at once, uncomment this. While libpng will not
290 * normally need that much memory in a chunk (unless you load up a very
291 * large file), zlib needs to know how big of a chunk it can use, and
292 * libpng thus makes sure to check any memory allocation to verify it
293 * will fit into memory.
295 * zlib provides 'MAXSEG_64K' which, if defined, indicates the
296 * same limit and pngconf.h (already included) sets the limit
297 * if certain operating systems are detected.
299 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K)
300 # define PNG_MAX_MALLOC_64K
301 #endif
303 #ifndef PNG_UNUSED
304 /* Unused formal parameter warnings are silenced using the following macro
305 * which is expected to have no bad effects on performance (optimizing
306 * compilers will probably remove it entirely). Note that if you replace
307 * it with something other than whitespace, you must include the terminating
308 * semicolon.
310 # define PNG_UNUSED(param) (void)param;
311 #endif
313 /* Just a little check that someone hasn't tried to define something
314 * contradictory.
316 #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K)
317 # undef PNG_ZBUF_SIZE
318 # define PNG_ZBUF_SIZE 65536L
319 #endif
321 /* If warnings or errors are turned off the code is disabled or redirected here.
322 * From 1.5.4 functions have been added to allow very limited formatting of
323 * error and warning messages - this code will also be disabled here.
325 #ifdef PNG_WARNINGS_SUPPORTED
326 # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p;
327 #else
328 # define png_warning(s1,s2) ((void)(s1))
329 # define png_chunk_warning(s1,s2) ((void)(s1))
330 # define png_warning_parameter(p,number,string) ((void)0)
331 # define png_warning_parameter_unsigned(p,number,format,value) ((void)0)
332 # define png_warning_parameter_signed(p,number,format,value) ((void)0)
333 # define png_formatted_warning(pp,p,message) ((void)(pp))
334 # define PNG_WARNING_PARAMETERS(p)
335 #endif
336 #ifndef PNG_ERROR_TEXT_SUPPORTED
337 # define png_error(s1,s2) png_err(s1)
338 # define png_chunk_error(s1,s2) png_err(s1)
339 # define png_fixed_error(s1,s2) png_err(s1)
340 #endif
342 /* C allows up-casts from (void*) to any pointer and (const void*) to any
343 * pointer to a const object. C++ regards this as a type error and requires an
344 * explicit, static, cast and provides the static_cast<> rune to ensure that
345 * const is not cast away.
347 #ifdef __cplusplus
348 # define png_voidcast(type, value) static_cast<type>(value)
349 # define png_constcast(type, value) const_cast<type>(value)
350 # define png_aligncast(type, value) \
351 static_cast<type>(static_cast<void*>(value))
352 # define png_aligncastconst(type, value) \
353 static_cast<type>(static_cast<const void*>(value))
354 #else
355 # define png_voidcast(type, value) (value)
356 # define png_constcast(type, value) ((type)(value))
357 # define png_aligncast(type, value) ((void*)(value))
358 # define png_aligncastconst(type, value) ((const void*)(value))
359 #endif /* __cplusplus */
361 /* Some fixed point APIs are still required even if not exported because
362 * they get used by the corresponding floating point APIs. This magic
363 * deals with this:
365 #ifdef PNG_FIXED_POINT_SUPPORTED
366 # define PNGFAPI PNGAPI
367 #else
368 # define PNGFAPI /* PRIVATE */
369 #endif
371 #ifndef PNG_VERSION_INFO_ONLY
372 /* Other defines specific to compilers can go here. Try to keep
373 * them inside an appropriate ifdef/endif pair for portability.
375 #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\
376 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)
377 /* png.c requires the following ANSI-C constants if the conversion of
378 * floating point to ASCII is implemented therein:
380 * DBL_DIG Maximum number of decimal digits (can be set to any constant)
381 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value)
382 * DBL_MAX Maximum floating point number (can be set to an arbitrary value)
384 # include <float.h>
386 # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \
387 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC)
388 /* We need to check that <math.h> hasn't already been included earlier
389 * as it seems it doesn't agree with <fp.h>, yet we should really use
390 * <fp.h> if possible.
392 # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__)
393 # include <fp.h>
394 # endif
395 # else
396 # include <math.h>
397 # endif
398 # if defined(_AMIGA) && defined(__SASC) && defined(_M68881)
399 /* Amiga SAS/C: We must include builtin FPU functions when compiling using
400 * MATH=68881
402 # include <m68881.h>
403 # endif
404 #endif
406 /* This provides the non-ANSI (far) memory allocation routines. */
407 #if defined(__TURBOC__) && defined(__MSDOS__)
408 # include <mem.h>
409 # include <alloc.h>
410 #endif
412 #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \
413 defined(_WIN32) || defined(__WIN32__)
414 # include <windows.h> /* defines _WINDOWS_ macro */
415 #endif
416 #endif /* PNG_VERSION_INFO_ONLY */
418 /* Moved here around 1.5.0beta36 from pngconf.h */
419 /* Users may want to use these so they are not private. Any library
420 * functions that are passed far data must be model-independent.
423 /* Memory model/platform independent fns */
424 #ifndef PNG_ABORT
425 # ifdef _WINDOWS_
426 # define PNG_ABORT() ExitProcess(0)
427 # else
428 # define PNG_ABORT() abort()
429 # endif
430 #endif
432 /* These macros may need to be architecture dependent. */
433 #define PNG_ALIGN_NONE 0 /* do not use data alignment */
434 #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */
435 #ifdef offsetof
436 # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */
437 #else
438 # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */
439 #endif
440 #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */
442 #ifndef PNG_ALIGN_TYPE
443 /* Default to using aligned access optimizations and requiring alignment to a
444 * multiple of the data type size. Override in a compiler specific fashion
445 * if necessary by inserting tests here:
447 # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE
448 #endif
450 #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE
451 /* This is used because in some compiler implementations non-aligned
452 * structure members are supported, so the offsetof approach below fails.
453 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access
454 * is good for performance. Do not do this unless you have tested the result
455 * and understand it.
457 # define png_alignof(type) (sizeof (type))
458 #else
459 # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET
460 # define png_alignof(type) offsetof(struct{char c; type t;}, t)
461 # else
462 # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS
463 # define png_alignof(type) (1)
464 # endif
465 /* Else leave png_alignof undefined to prevent use thereof */
466 # endif
467 #endif
469 /* This implicitly assumes alignment is always to a power of 2. */
470 #ifdef png_alignof
471 # define png_isaligned(ptr, type)\
472 ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0)
473 #else
474 # define png_isaligned(ptr, type) 0
475 #endif
477 /* End of memory model/platform independent support */
478 /* End of 1.5.0beta36 move from pngconf.h */
480 /* CONSTANTS and UTILITY MACROS
481 * These are used internally by libpng and not exposed in the API
484 /* Various modes of operation. Note that after an init, mode is set to
485 * zero automatically when the structure is created. Three of these
486 * are defined in png.h because they need to be visible to applications
487 * that call png_set_unknown_chunk().
489 /* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
490 /* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
491 #define PNG_HAVE_IDAT 0x04
492 /* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
493 #define PNG_HAVE_IEND 0x10
494 /* 0x20 (unused) */
495 /* 0x40 (unused) */
496 /* 0x80 (unused) */
497 #define PNG_HAVE_CHUNK_HEADER 0x100
498 #define PNG_WROTE_tIME 0x200
499 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400
500 #define PNG_BACKGROUND_IS_GRAY 0x800
501 #define PNG_HAVE_PNG_SIGNATURE 0x1000
502 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */
503 /* 0x4000 (unused) */
504 #define PNG_IS_READ_STRUCT 0x8000 /* Else is a write struct */
506 /* Flags for the transformations the PNG library does on the image data */
507 #define PNG_BGR 0x0001
508 #define PNG_INTERLACE 0x0002
509 #define PNG_PACK 0x0004
510 #define PNG_SHIFT 0x0008
511 #define PNG_SWAP_BYTES 0x0010
512 #define PNG_INVERT_MONO 0x0020
513 #define PNG_QUANTIZE 0x0040
514 #define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
515 #define PNG_BACKGROUND_EXPAND 0x0100
516 #define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
517 #define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
518 #define PNG_RGBA 0x0800
519 #define PNG_EXPAND 0x1000
520 #define PNG_GAMMA 0x2000
521 #define PNG_GRAY_TO_RGB 0x4000
522 #define PNG_FILLER 0x8000
523 #define PNG_PACKSWAP 0x10000
524 #define PNG_SWAP_ALPHA 0x20000
525 #define PNG_STRIP_ALPHA 0x40000
526 #define PNG_INVERT_ALPHA 0x80000
527 #define PNG_USER_TRANSFORM 0x100000
528 #define PNG_RGB_TO_GRAY_ERR 0x200000
529 #define PNG_RGB_TO_GRAY_WARN 0x400000
530 #define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
531 #define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
532 #define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
533 #define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
534 #define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
535 /* 0x8000000 unused */
536 /* 0x10000000 unused */
537 /* 0x20000000 unused */
538 /* 0x40000000 unused */
539 /* Flags for png_create_struct */
540 #define PNG_STRUCT_PNG 0x0001
541 #define PNG_STRUCT_INFO 0x0002
543 /* Scaling factor for filter heuristic weighting calculations */
544 #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT))
545 #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT))
547 /* Flags for the png_ptr->flags rather than declaring a byte for each one */
548 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001
549 #define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002 /* Added to libpng-1.6.0 */
550 /* 0x0004 unused */
551 #define PNG_FLAG_ZSTREAM_ENDED 0x0008 /* Added to libpng-1.6.0 */
552 /* 0x0010 unused */
553 /* 0x0020 unused */
554 #define PNG_FLAG_ROW_INIT 0x0040
555 #define PNG_FLAG_FILLER_AFTER 0x0080
556 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100
557 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
558 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400
559 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
560 #define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
561 #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
562 #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
563 /* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000 */
564 /* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000 */
565 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000
566 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
567 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
568 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000 /* Added to libpng-1.4.0 */
569 #define PNG_FLAG_APP_WARNINGS_WARN 0x200000 /* Added to libpng-1.6.0 */
570 #define PNG_FLAG_APP_ERRORS_WARN 0x400000 /* Added to libpng-1.6.0 */
571 /* 0x800000 unused */
572 /* 0x1000000 unused */
573 /* 0x2000000 unused */
574 /* 0x4000000 unused */
575 /* 0x8000000 unused */
576 /* 0x10000000 unused */
577 /* 0x20000000 unused */
578 /* 0x40000000 unused */
580 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
581 PNG_FLAG_CRC_ANCILLARY_NOWARN)
583 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \
584 PNG_FLAG_CRC_CRITICAL_IGNORE)
586 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \
587 PNG_FLAG_CRC_CRITICAL_MASK)
589 /* Save typing and make code easier to understand */
591 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \
592 abs((int)((c1).green) - (int)((c2).green)) + \
593 abs((int)((c1).blue) - (int)((c2).blue)))
595 /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255
596 * by dividing by 257 *with rounding*. This macro is exact for the given range.
597 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the
598 * macro were established by experiment (modifying the added value). The macro
599 * has a second variant that takes a value already scaled by 255 and divides by
600 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it
601 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values.
603 #define PNG_DIV65535(v24) (((v24) + 32895) >> 16)
604 #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255)
606 /* Added to libpng-1.2.6 JB */
607 #define PNG_ROWBYTES(pixel_bits, width) \
608 ((pixel_bits) >= 8 ? \
609 ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \
610 (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) )
612 /* PNG_OUT_OF_RANGE returns true if value is outside the range
613 * ideal-delta..ideal+delta. Each argument is evaluated twice.
614 * "ideal" and "delta" should be constants, normally simple
615 * integers, "value" a variable. Added to libpng-1.2.6 JB
617 #define PNG_OUT_OF_RANGE(value, ideal, delta) \
618 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) )
620 /* Conversions between fixed and floating point, only defined if
621 * required (to make sure the code doesn't accidentally use float
622 * when it is supposedly disabled.)
624 #ifdef PNG_FLOATING_POINT_SUPPORTED
625 /* The floating point conversion can't overflow, though it can and
626 * does lose accuracy relative to the original fixed point value.
627 * In practice this doesn't matter because png_fixed_point only
628 * stores numbers with very low precision. The png_ptr and s
629 * arguments are unused by default but are there in case error
630 * checking becomes a requirement.
632 #define png_float(png_ptr, fixed, s) (.00001 * (fixed))
634 /* The fixed point conversion performs range checking and evaluates
635 * its argument multiple times, so must be used with care. The
636 * range checking uses the PNG specification values for a signed
637 * 32 bit fixed point value except that the values are deliberately
638 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly
639 * (2^31-1) * 100000). 's' is a string that describes the value being
640 * converted.
642 * NOTE: this macro will raise a png_error if the range check fails,
643 * therefore it is normally only appropriate to use this on values
644 * that come from API calls or other sources where an out of range
645 * error indicates a programming error, not a data error!
647 * NOTE: by default this is off - the macro is not used - because the
648 * function call saves a lot of code.
650 #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED
651 #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\
652 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0))
653 #endif
654 /* else the corresponding function is defined below, inside the scope of the
655 * cplusplus test.
657 #endif
659 /* Constants for known chunk types. If you need to add a chunk, define the name
660 * here. For historical reasons these constants have the form png_<name>; i.e.
661 * the prefix is lower case. Please use decimal values as the parameters to
662 * match the ISO PNG specification and to avoid relying on the C locale
663 * interpretation of character values.
665 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
666 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
667 * to be generated if required.
669 * PNG_32b correctly produces a value shifted by up to 24 bits, even on
670 * architectures where (int) is only 16 bits.
672 #define PNG_32b(b,s) ((png_uint_32)(b) << (s))
673 #define PNG_U32(b1,b2,b3,b4) \
674 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
676 /* Constants for known chunk types.
678 * MAINTAINERS: If you need to add a chunk, define the name here.
679 * For historical reasons these constants have the form png_<name>; i.e.
680 * the prefix is lower case. Please use decimal values as the parameters to
681 * match the ISO PNG specification and to avoid relying on the C locale
682 * interpretation of character values. Please keep the list sorted.
684 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk
685 * type. In fact the specification does not express chunk types this way,
686 * however using a 32-bit value means that the chunk type can be read from the
687 * stream using exactly the same code as used for a 32-bit unsigned value and
688 * can be examined far more efficiently (using one arithmetic compare).
690 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The
691 * libpng API still uses strings for 'unknown' chunks and a macro,
692 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice
693 * that for portable code numeric values must still be used; the string "IHDR"
694 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R').
696 * In 1.7.0 the definitions will be made public in png.h to avoid having to
697 * duplicate the same definitions in application code.
699 #define png_IDAT PNG_U32( 73, 68, 65, 84)
700 #define png_IEND PNG_U32( 73, 69, 78, 68)
701 #define png_IHDR PNG_U32( 73, 72, 68, 82)
702 #define png_PLTE PNG_U32( 80, 76, 84, 69)
703 #define png_bKGD PNG_U32( 98, 75, 71, 68)
704 #define png_cHRM PNG_U32( 99, 72, 82, 77)
705 #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */
706 #define png_gAMA PNG_U32(103, 65, 77, 65)
707 #define png_gIFg PNG_U32(103, 73, 70, 103)
708 #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */
709 #define png_gIFx PNG_U32(103, 73, 70, 120)
710 #define png_hIST PNG_U32(104, 73, 83, 84)
711 #define png_iCCP PNG_U32(105, 67, 67, 80)
712 #define png_iTXt PNG_U32(105, 84, 88, 116)
713 #define png_oFFs PNG_U32(111, 70, 70, 115)
714 #define png_pCAL PNG_U32(112, 67, 65, 76)
715 #define png_pHYs PNG_U32(112, 72, 89, 115)
716 #define png_sBIT PNG_U32(115, 66, 73, 84)
717 #define png_sCAL PNG_U32(115, 67, 65, 76)
718 #define png_sPLT PNG_U32(115, 80, 76, 84)
719 #define png_sRGB PNG_U32(115, 82, 71, 66)
720 #define png_sTER PNG_U32(115, 84, 69, 82)
721 #define png_tEXt PNG_U32(116, 69, 88, 116)
722 #define png_tIME PNG_U32(116, 73, 77, 69)
723 #define png_tRNS PNG_U32(116, 82, 78, 83)
724 #define png_zTXt PNG_U32(122, 84, 88, 116)
726 /* The following will work on (signed char*) strings, whereas the get_uint_32
727 * macro will fail on top-bit-set values because of the sign extension.
729 #define PNG_CHUNK_FROM_STRING(s)\
730 PNG_U32(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
732 /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
733 * signed and the argument is a (char[]) This macro will fail miserably on
734 * systems where (char) is more than 8 bits.
736 #define PNG_STRING_FROM_CHUNK(s,c)\
737 (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
738 ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
740 /* Do the same but terminate with a null character. */
741 #define PNG_CSTRING_FROM_CHUNK(s,c)\
742 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
744 /* Test on flag values as defined in the spec (section 5.4): */
745 #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29))
746 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c))
747 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
748 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
749 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
751 /* Gamma values (new at libpng-1.5.4): */
752 #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
753 #define PNG_GAMMA_MAC_INVERSE 65909
754 #define PNG_GAMMA_sRGB_INVERSE 45455
756 /* Almost everything below is C specific; the #defines above can be used in
757 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot.
759 #ifndef PNG_VERSION_INFO_ONLY
761 #include "pngstruct.h"
762 #include "pnginfo.h"
764 /* Validate the include paths - the include path used to generate pnglibconf.h
765 * must match that used in the build, or we must be using pnglibconf.h.prebuilt:
767 #if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM
768 # error ZLIB_VERNUM != PNG_ZLIB_VERNUM \
769 "-I (include path) error: see the notes in pngpriv.h"
770 /* This means that when pnglibconf.h was built the copy of zlib.h that it
771 * used is not the same as the one being used here. Because the build of
772 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the
773 * zlib version number and because this affects handling of certain broken
774 * PNG files the -I directives must match.
776 * The most likely explanation is that you passed a -I in CFLAGS, this will
777 * not work; all the preprocessor directories and in particular all the -I
778 * directives must be in CPPFLAGS.
780 #endif
782 /* This is used for 16 bit gamma tables -- only the top level pointers are
783 * const; this could be changed:
785 typedef const png_uint_16p * png_const_uint_16pp;
787 /* Added to libpng-1.5.7: sRGB conversion tables */
788 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
789 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
790 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED
791 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]);
792 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value,
793 * 0..65535. This table gives the closest 16-bit answers (no errors).
795 #endif
797 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]);
798 PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]);
800 #define PNG_sRGB_FROM_LINEAR(linear) ((png_byte)((png_sRGB_base[(linear)>>15] +\
801 ((((linear)&0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8))
802 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB
803 * encoded value with maximum error 0.646365. Note that the input is not a
804 * 16-bit value; it has been multiplied by 255! */
805 #endif /* PNG_SIMPLIFIED_READ/WRITE */
808 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */
809 #ifdef __cplusplus
810 extern "C" {
811 #endif /* __cplusplus */
813 /* Internal functions; these are not exported from a DLL however because they
814 * are used within several of the C source files they have to be C extern.
816 * All of these functions must be declared with PNG_INTERNAL_FUNCTION.
819 /* Zlib support */
820 #define PNG_UNEXPECTED_ZLIB_RETURN (-7)
821 PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret),
822 PNG_EMPTY);
823 /* Used by the zlib handling functions to ensure that z_stream::msg is always
824 * set before they return.
827 #ifdef PNG_WRITE_SUPPORTED
828 PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr,
829 png_compression_bufferp *list),PNG_EMPTY);
830 /* Free the buffer list used by the compressed write code. */
831 #endif
833 #if defined(PNG_FLOATING_POINT_SUPPORTED) && \
834 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \
835 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \
836 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \
837 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \
838 (defined(PNG_sCAL_SUPPORTED) && \
839 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED))
840 PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr,
841 double fp, png_const_charp text),PNG_EMPTY);
842 #endif
844 /* Check the user version string for compatibility, returns false if the version
845 * numbers aren't compatible.
847 PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr,
848 png_const_charp user_png_ver),PNG_EMPTY);
850 /* Internal base allocator - no messages, NULL on failure to allocate. This
851 * does, however, call the application provided allocator and that could call
852 * png_error (although that would be a bug in the application implementation.)
854 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr,
855 png_alloc_size_t size),PNG_ALLOCATED);
857 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
858 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
859 /* Internal array allocator, outputs no error or warning messages on failure,
860 * just returns NULL.
862 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr,
863 int nelements, size_t element_size),PNG_ALLOCATED);
865 /* The same but an existing array is extended by add_elements. This function
866 * also memsets the new elements to 0 and copies the old elements. The old
867 * array is not freed or altered.
869 PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr,
870 png_const_voidp array, int old_elements, int add_elements,
871 size_t element_size),PNG_ALLOCATED);
872 #endif /* text, sPLT or unknown chunks */
874 /* Magic to create a struct when there is no struct to call the user supplied
875 * memory allocators. Because error handling has not been set up the memory
876 * handlers can't safely call png_error, but this is an obscure and undocumented
877 * restriction so libpng has to assume that the 'free' handler, at least, might
878 * call png_error.
880 PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct,
881 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn,
882 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn,
883 png_free_ptr free_fn),PNG_ALLOCATED);
885 /* Free memory from internal libpng struct */
886 PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr),
887 PNG_EMPTY);
889 /* Free an allocated jmp_buf (always succeeds) */
890 PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY);
892 /* Function to allocate memory for zlib. PNGAPI is disallowed. */
893 PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size),
894 PNG_ALLOCATED);
896 /* Function to free memory for zlib. PNGAPI is disallowed. */
897 PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY);
899 /* Next four functions are used internally as callbacks. PNGCBAPI is required
900 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to
901 * PNGCBAPI at 1.5.0
904 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr,
905 png_bytep data, png_size_t length),PNG_EMPTY);
907 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
908 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr,
909 png_bytep buffer, png_size_t length),PNG_EMPTY);
910 #endif
912 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr,
913 png_bytep data, png_size_t length),PNG_EMPTY);
915 #ifdef PNG_WRITE_FLUSH_SUPPORTED
916 # ifdef PNG_STDIO_SUPPORTED
917 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr),
918 PNG_EMPTY);
919 # endif
920 #endif
922 /* Reset the CRC variable */
923 PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY);
925 /* Write the "data" buffer to whatever output you are using */
926 PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr,
927 png_const_bytep data, png_size_t length),PNG_EMPTY);
929 /* Read and check the PNG file signature */
930 PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr,
931 png_inforp info_ptr),PNG_EMPTY);
933 /* Read the chunk header (length + type name) */
934 PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr),
935 PNG_EMPTY);
937 /* Read data from whatever input you are using into the "data" buffer */
938 PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data,
939 png_size_t length),PNG_EMPTY);
941 /* Read bytes into buf, and update png_ptr->crc */
942 PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf,
943 png_uint_32 length),PNG_EMPTY);
945 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */
946 PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr,
947 png_uint_32 skip),PNG_EMPTY);
949 /* Read the CRC from the file and compare it to the libpng calculated CRC */
950 PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY);
952 /* Calculate the CRC over a section of data. Note that we are only
953 * passing a maximum of 64K on systems that have this as a memory limit,
954 * since this is the maximum buffer size we can specify.
956 PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr,
957 png_const_bytep ptr, png_size_t length),PNG_EMPTY);
959 #ifdef PNG_WRITE_FLUSH_SUPPORTED
960 PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY);
961 #endif
963 /* Write various chunks */
965 /* Write the IHDR chunk, and update the png_struct with the necessary
966 * information.
968 PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr,
969 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type,
970 int compression_method, int filter_method, int interlace_method),PNG_EMPTY);
972 PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr,
973 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY);
975 PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr,
976 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush),
977 PNG_EMPTY);
979 PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY);
981 #ifdef PNG_WRITE_gAMA_SUPPORTED
982 PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr,
983 png_fixed_point file_gamma),PNG_EMPTY);
984 #endif
986 #ifdef PNG_WRITE_sBIT_SUPPORTED
987 PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr,
988 png_const_color_8p sbit, int color_type),PNG_EMPTY);
989 #endif
991 #ifdef PNG_WRITE_cHRM_SUPPORTED
992 PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr,
993 const png_xy *xy), PNG_EMPTY);
994 /* The xy value must have been previously validated */
995 #endif
997 #ifdef PNG_WRITE_sRGB_SUPPORTED
998 PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr,
999 int intent),PNG_EMPTY);
1000 #endif
1002 #ifdef PNG_WRITE_iCCP_SUPPORTED
1003 PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr,
1004 png_const_charp name, png_const_bytep profile), PNG_EMPTY);
1005 /* The profile must have been previously validated for correctness, the
1006 * length comes from the first four bytes. Only the base, deflate,
1007 * compression is supported.
1009 #endif
1011 #ifdef PNG_WRITE_sPLT_SUPPORTED
1012 PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr,
1013 png_const_sPLT_tp palette),PNG_EMPTY);
1014 #endif
1016 #ifdef PNG_WRITE_tRNS_SUPPORTED
1017 PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr,
1018 png_const_bytep trans, png_const_color_16p values, int number,
1019 int color_type),PNG_EMPTY);
1020 #endif
1022 #ifdef PNG_WRITE_bKGD_SUPPORTED
1023 PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr,
1024 png_const_color_16p values, int color_type),PNG_EMPTY);
1025 #endif
1027 #ifdef PNG_WRITE_hIST_SUPPORTED
1028 PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr,
1029 png_const_uint_16p hist, int num_hist),PNG_EMPTY);
1030 #endif
1032 /* Chunks that have keywords */
1033 #ifdef PNG_WRITE_tEXt_SUPPORTED
1034 PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr,
1035 png_const_charp key, png_const_charp text, png_size_t text_len),PNG_EMPTY);
1036 #endif
1038 #ifdef PNG_WRITE_zTXt_SUPPORTED
1039 PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp
1040 key, png_const_charp text, png_size_t text_len, int compression),PNG_EMPTY);
1041 #endif
1043 #ifdef PNG_WRITE_iTXt_SUPPORTED
1044 PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr,
1045 int compression, png_const_charp key, png_const_charp lang,
1046 png_const_charp lang_key, png_const_charp text),PNG_EMPTY);
1047 #endif
1049 #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */
1050 PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr,
1051 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY);
1052 #endif
1054 #ifdef PNG_WRITE_oFFs_SUPPORTED
1055 PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr,
1056 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY);
1057 #endif
1059 #ifdef PNG_WRITE_pCAL_SUPPORTED
1060 PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr,
1061 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
1062 png_const_charp units, png_charpp params),PNG_EMPTY);
1063 #endif
1065 #ifdef PNG_WRITE_pHYs_SUPPORTED
1066 PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr,
1067 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit,
1068 int unit_type),PNG_EMPTY);
1069 #endif
1071 #ifdef PNG_WRITE_tIME_SUPPORTED
1072 PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr,
1073 png_const_timep mod_time),PNG_EMPTY);
1074 #endif
1076 #ifdef PNG_WRITE_sCAL_SUPPORTED
1077 PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr,
1078 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY);
1079 #endif
1081 /* Called when finished processing a row of data */
1082 PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr),
1083 PNG_EMPTY);
1085 /* Internal use only. Called before first row of data */
1086 PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr),
1087 PNG_EMPTY);
1089 /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
1090 * array of png_ptr->width pixels. If the image is not interlaced or this
1091 * is the final pass this just does a memcpy, otherwise the "display" flag
1092 * is used to determine whether to copy pixels that are not in the current pass.
1094 * Because 'png_do_read_interlace' (below) replicates pixels this allows this
1095 * function to achieve the documented 'blocky' appearance during interlaced read
1096 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
1097 * are not changed if they are not in the current pass, when display is 0.
1099 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
1101 * The API always reads from the png_struct row buffer and always assumes that
1102 * it is full width (png_do_read_interlace has already been called.)
1104 * This function is only ever used to write to row buffers provided by the
1105 * caller of the relevant libpng API and the row must have already been
1106 * transformed by the read transformations.
1108 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
1109 * bitmasks for use within the code, otherwise runtime generated masks are used.
1110 * The default is compile time masks.
1112 #ifndef PNG_USE_COMPILE_TIME_MASKS
1113 # define PNG_USE_COMPILE_TIME_MASKS 1
1114 #endif
1115 PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr,
1116 png_bytep row, int display),PNG_EMPTY);
1118 #ifdef PNG_READ_INTERLACING_SUPPORTED
1119 /* Expand an interlaced row: the 'row_info' describes the pass data that has
1120 * been read in and must correspond to the pixels in 'row', the pixels are
1121 * expanded (moved apart) in 'row' to match the final layout, when doing this
1122 * the pixels are *replicated* to the intervening space. This is essential for
1123 * the correct operation of png_combine_row, above.
1125 PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info,
1126 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY);
1127 #endif
1129 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
1131 #ifdef PNG_WRITE_INTERLACING_SUPPORTED
1132 /* Grab pixels out of a row for an interlaced pass */
1133 PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info,
1134 png_bytep row, int pass),PNG_EMPTY);
1135 #endif
1137 /* Unfilter a row: check the filter value before calling this, there is no point
1138 * calling it for PNG_FILTER_VALUE_NONE.
1140 PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop
1141 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY);
1143 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info,
1144 png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1145 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop
1146 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1147 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop
1148 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1149 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop
1150 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1151 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop
1152 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1153 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop
1154 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1155 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop
1156 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY);
1158 /* Choose the best filter to use and filter the row data */
1159 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr,
1160 png_row_infop row_info),PNG_EMPTY);
1162 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED
1163 PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr,
1164 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY);
1165 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer
1166 * is NULL the function checks, instead, for the end of the stream. In this
1167 * case a benign error will be issued if the stream end is not found or if
1168 * extra data has to be consumed.
1170 PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr),
1171 PNG_EMPTY);
1172 /* This cleans up when the IDAT LZ stream does not end when the last image
1173 * byte is read; there is still some pending input.
1176 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr),
1177 PNG_EMPTY);
1178 /* Finish a row while reading, dealing with interlacing passes, etc. */
1179 #endif
1181 /* Initialize the row buffers, etc. */
1182 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY);
1184 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1185 /* Optional call to update the users info structure */
1186 PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr,
1187 png_inforp info_ptr),PNG_EMPTY);
1188 #endif
1190 /* These are the functions that do the transformations */
1191 #ifdef PNG_READ_FILLER_SUPPORTED
1192 PNG_INTERNAL_FUNCTION(void,png_do_read_filler,(png_row_infop row_info,
1193 png_bytep row, png_uint_32 filler, png_uint_32 flags),PNG_EMPTY);
1194 #endif
1196 #ifdef PNG_READ_SWAP_ALPHA_SUPPORTED
1197 PNG_INTERNAL_FUNCTION(void,png_do_read_swap_alpha,(png_row_infop row_info,
1198 png_bytep row),PNG_EMPTY);
1199 #endif
1201 #ifdef PNG_WRITE_SWAP_ALPHA_SUPPORTED
1202 PNG_INTERNAL_FUNCTION(void,png_do_write_swap_alpha,(png_row_infop row_info,
1203 png_bytep row),PNG_EMPTY);
1204 #endif
1206 #ifdef PNG_READ_INVERT_ALPHA_SUPPORTED
1207 PNG_INTERNAL_FUNCTION(void,png_do_read_invert_alpha,(png_row_infop row_info,
1208 png_bytep row),PNG_EMPTY);
1209 #endif
1211 #ifdef PNG_WRITE_INVERT_ALPHA_SUPPORTED
1212 PNG_INTERNAL_FUNCTION(void,png_do_write_invert_alpha,(png_row_infop row_info,
1213 png_bytep row),PNG_EMPTY);
1214 #endif
1216 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \
1217 defined(PNG_READ_STRIP_ALPHA_SUPPORTED)
1218 PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info,
1219 png_bytep row, int at_start),PNG_EMPTY);
1220 #endif
1222 #ifdef PNG_16BIT_SUPPORTED
1223 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED)
1224 PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info,
1225 png_bytep row),PNG_EMPTY);
1226 #endif
1227 #endif
1229 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \
1230 defined(PNG_WRITE_PACKSWAP_SUPPORTED)
1231 PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info,
1232 png_bytep row),PNG_EMPTY);
1233 #endif
1235 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1236 PNG_INTERNAL_FUNCTION(int,png_do_rgb_to_gray,(png_structrp png_ptr,
1237 png_row_infop row_info, png_bytep row),PNG_EMPTY);
1238 #endif
1240 #ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
1241 PNG_INTERNAL_FUNCTION(void,png_do_gray_to_rgb,(png_row_infop row_info,
1242 png_bytep row),PNG_EMPTY);
1243 #endif
1245 #ifdef PNG_READ_PACK_SUPPORTED
1246 PNG_INTERNAL_FUNCTION(void,png_do_unpack,(png_row_infop row_info,
1247 png_bytep row),PNG_EMPTY);
1248 #endif
1250 #ifdef PNG_READ_SHIFT_SUPPORTED
1251 PNG_INTERNAL_FUNCTION(void,png_do_unshift,(png_row_infop row_info,
1252 png_bytep row, png_const_color_8p sig_bits),PNG_EMPTY);
1253 #endif
1255 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED)
1256 PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info,
1257 png_bytep row),PNG_EMPTY);
1258 #endif
1260 #ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
1261 PNG_INTERNAL_FUNCTION(void,png_do_scale_16_to_8,(png_row_infop row_info,
1262 png_bytep row),PNG_EMPTY);
1263 #endif
1265 #ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
1266 PNG_INTERNAL_FUNCTION(void,png_do_chop,(png_row_infop row_info,
1267 png_bytep row),PNG_EMPTY);
1268 #endif
1270 #ifdef PNG_READ_QUANTIZE_SUPPORTED
1271 PNG_INTERNAL_FUNCTION(void,png_do_quantize,(png_row_infop row_info,
1272 png_bytep row, png_const_bytep palette_lookup,
1273 png_const_bytep quantize_lookup),PNG_EMPTY);
1275 # ifdef PNG_CORRECT_PALETTE_SUPPORTED
1276 PNG_INTERNAL_FUNCTION(void,png_correct_palette,(png_structrp png_ptr,
1277 png_colorp palette, int num_palette),PNG_EMPTY);
1278 # endif
1279 #endif
1281 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED)
1282 PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info,
1283 png_bytep row),PNG_EMPTY);
1284 #endif
1286 #ifdef PNG_WRITE_PACK_SUPPORTED
1287 PNG_INTERNAL_FUNCTION(void,png_do_pack,(png_row_infop row_info,
1288 png_bytep row, png_uint_32 bit_depth),PNG_EMPTY);
1289 #endif
1291 #ifdef PNG_WRITE_SHIFT_SUPPORTED
1292 PNG_INTERNAL_FUNCTION(void,png_do_shift,(png_row_infop row_info,
1293 png_bytep row, png_const_color_8p bit_depth),PNG_EMPTY);
1294 #endif
1296 #if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
1297 defined(PNG_READ_ALPHA_MODE_SUPPORTED)
1298 PNG_INTERNAL_FUNCTION(void,png_do_compose,(png_row_infop row_info,
1299 png_bytep row, png_structrp png_ptr),PNG_EMPTY);
1300 #endif
1302 #ifdef PNG_READ_GAMMA_SUPPORTED
1303 PNG_INTERNAL_FUNCTION(void,png_do_gamma,(png_row_infop row_info,
1304 png_bytep row, png_structrp png_ptr),PNG_EMPTY);
1305 #endif
1307 #ifdef PNG_READ_ALPHA_MODE_SUPPORTED
1308 PNG_INTERNAL_FUNCTION(void,png_do_encode_alpha,(png_row_infop row_info,
1309 png_bytep row, png_structrp png_ptr),PNG_EMPTY);
1310 #endif
1312 #ifdef PNG_READ_EXPAND_SUPPORTED
1313 PNG_INTERNAL_FUNCTION(void,png_do_expand_palette,(png_row_infop row_info,
1314 png_bytep row, png_const_colorp palette, png_const_bytep trans,
1315 int num_trans),PNG_EMPTY);
1316 PNG_INTERNAL_FUNCTION(void,png_do_expand,(png_row_infop row_info,
1317 png_bytep row, png_const_color_16p trans_color),PNG_EMPTY);
1318 #endif
1320 #ifdef PNG_READ_EXPAND_16_SUPPORTED
1321 PNG_INTERNAL_FUNCTION(void,png_do_expand_16,(png_row_infop row_info,
1322 png_bytep row),PNG_EMPTY);
1323 #endif
1325 /* The following decodes the appropriate chunks, and does error correction,
1326 * then calls the appropriate callback for the chunk if it is valid.
1329 /* Decode the IHDR chunk */
1330 PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr,
1331 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1332 PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr,
1333 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1334 PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr,
1335 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1337 #ifdef PNG_READ_bKGD_SUPPORTED
1338 PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr,
1339 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1340 #endif
1342 #ifdef PNG_READ_cHRM_SUPPORTED
1343 PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr,
1344 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1345 #endif
1347 #ifdef PNG_READ_gAMA_SUPPORTED
1348 PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr,
1349 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1350 #endif
1352 #ifdef PNG_READ_hIST_SUPPORTED
1353 PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr,
1354 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1355 #endif
1357 #ifdef PNG_READ_iCCP_SUPPORTED
1358 PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr,
1359 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1360 #endif /* PNG_READ_iCCP_SUPPORTED */
1362 #ifdef PNG_READ_iTXt_SUPPORTED
1363 PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr,
1364 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1365 #endif
1367 #ifdef PNG_READ_oFFs_SUPPORTED
1368 PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr,
1369 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1370 #endif
1372 #ifdef PNG_READ_pCAL_SUPPORTED
1373 PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr,
1374 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1375 #endif
1377 #ifdef PNG_READ_pHYs_SUPPORTED
1378 PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr,
1379 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1380 #endif
1382 #ifdef PNG_READ_sBIT_SUPPORTED
1383 PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr,
1384 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1385 #endif
1387 #ifdef PNG_READ_sCAL_SUPPORTED
1388 PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr,
1389 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1390 #endif
1392 #ifdef PNG_READ_sPLT_SUPPORTED
1393 PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr,
1394 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1395 #endif /* PNG_READ_sPLT_SUPPORTED */
1397 #ifdef PNG_READ_sRGB_SUPPORTED
1398 PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr,
1399 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1400 #endif
1402 #ifdef PNG_READ_tEXt_SUPPORTED
1403 PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr,
1404 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1405 #endif
1407 #ifdef PNG_READ_tIME_SUPPORTED
1408 PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr,
1409 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1410 #endif
1412 #ifdef PNG_READ_tRNS_SUPPORTED
1413 PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr,
1414 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1415 #endif
1417 #ifdef PNG_READ_zTXt_SUPPORTED
1418 PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr,
1419 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1420 #endif
1422 PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr,
1423 png_uint_32 chunk_name),PNG_EMPTY);
1425 #ifdef PNG_READ_SUPPORTED
1426 PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr,
1427 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY);
1428 /* This is the function that gets called for unknown chunks. The 'keep'
1429 * argument is either non-zero for a known chunk that has been set to be
1430 * handled as unknown or zero for an unknown chunk. By default the function
1431 * just skips the chunk or errors out if it is critical.
1434 #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
1435 #ifdef PNG_SET_UNKNOWN_CHUNKS_SUPPORTED
1436 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling,
1437 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY);
1438 /* Exactly as the API png_handle_as_unknown() except that the argument is a
1439 * 32-bit chunk name, not a string.
1441 #endif
1442 #endif /* PNG_READ_UNKNOWN_CHUNKS_SUPPORTED */
1443 #endif /* PNG_READ_SUPPORTED */
1445 /* Handle the transformations for reading and writing */
1446 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1447 PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr,
1448 png_row_infop row_info),PNG_EMPTY);
1449 #endif
1450 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
1451 PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr,
1452 png_row_infop row_info),PNG_EMPTY);
1453 #endif
1455 #ifdef PNG_READ_TRANSFORMS_SUPPORTED
1456 PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr),
1457 PNG_EMPTY);
1458 #endif
1460 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED
1461 PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr,
1462 png_inforp info_ptr),PNG_EMPTY);
1463 PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr,
1464 png_inforp info_ptr),PNG_EMPTY);
1465 PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY);
1466 PNG_INTERNAL_FUNCTION(void,png_push_crc_skip,(png_structrp png_ptr,
1467 png_uint_32 length),PNG_EMPTY);
1468 PNG_INTERNAL_FUNCTION(void,png_push_crc_finish,(png_structrp png_ptr),
1469 PNG_EMPTY);
1470 PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr),
1471 PNG_EMPTY);
1472 PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr,
1473 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
1474 PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY);
1475 PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr,
1476 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY);
1477 PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr),
1478 PNG_EMPTY);
1479 PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr,
1480 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1481 PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr,
1482 png_inforp info_ptr),PNG_EMPTY);
1483 PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr,
1484 png_inforp info_ptr),PNG_EMPTY);
1485 PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr,
1486 png_bytep row),PNG_EMPTY);
1487 PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr,
1488 png_inforp info_ptr),PNG_EMPTY);
1489 PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr,
1490 png_inforp info_ptr),PNG_EMPTY);
1491 PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr),
1492 PNG_EMPTY);
1493 # ifdef PNG_READ_tEXt_SUPPORTED
1494 PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr,
1495 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1496 PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr,
1497 png_inforp info_ptr),PNG_EMPTY);
1498 # endif
1499 # ifdef PNG_READ_zTXt_SUPPORTED
1500 PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr,
1501 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1502 PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr,
1503 png_inforp info_ptr),PNG_EMPTY);
1504 # endif
1505 # ifdef PNG_READ_iTXt_SUPPORTED
1506 PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr,
1507 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY);
1508 PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr,
1509 png_inforp info_ptr),PNG_EMPTY);
1510 # endif
1512 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */
1514 #ifdef PNG_MNG_FEATURES_SUPPORTED
1515 PNG_INTERNAL_FUNCTION(void,png_do_read_intrapixel,(png_row_infop row_info,
1516 png_bytep row),PNG_EMPTY);
1517 PNG_INTERNAL_FUNCTION(void,png_do_write_intrapixel,(png_row_infop row_info,
1518 png_bytep row),PNG_EMPTY);
1519 #endif
1521 /* Added at libpng version 1.6.0 */
1522 #ifdef PNG_GAMMA_SUPPORTED
1523 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr,
1524 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY);
1525 /* Set the colorspace gamma with a value provided by the application or by
1526 * the gAMA chunk on read. The value will override anything set by an ICC
1527 * profile.
1530 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr,
1531 png_inforp info_ptr), PNG_EMPTY);
1532 /* Synchronize the info 'valid' flags with the colorspace */
1534 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr,
1535 png_inforp info_ptr), PNG_EMPTY);
1536 /* Copy the png_struct colorspace to the info_struct and call the above to
1537 * synchronize the flags. Checks for NULL info_ptr and does nothing.
1539 #endif
1541 /* Added at libpng version 1.4.0 */
1542 #ifdef PNG_COLORSPACE_SUPPORTED
1543 /* These internal functions are for maintaining the colorspace structure within
1544 * a png_info or png_struct (or, indeed, both).
1546 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities,
1547 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy,
1548 int preferred), PNG_EMPTY);
1550 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints,
1551 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ,
1552 int preferred), PNG_EMPTY);
1554 #ifdef PNG_sRGB_SUPPORTED
1555 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr,
1556 png_colorspacerp colorspace, int intent), PNG_EMPTY);
1557 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the
1558 * flags to write them, if it returns false there was a problem and an error
1559 * message has already been output (but the colorspace may still need to be
1560 * synced to record the invalid flag).
1562 #endif /* sRGB */
1564 #ifdef PNG_iCCP_SUPPORTED
1565 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr,
1566 png_colorspacerp colorspace, png_const_charp name,
1567 png_uint_32 profile_length, png_const_bytep profile, int color_type),
1568 PNG_EMPTY);
1569 /* The 'name' is used for information only */
1571 /* Routines for checking parts of an ICC profile. */
1572 PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr,
1573 png_colorspacerp colorspace, png_const_charp name,
1574 png_uint_32 profile_length), PNG_EMPTY);
1575 PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr,
1576 png_colorspacerp colorspace, png_const_charp name,
1577 png_uint_32 profile_length,
1578 png_const_bytep profile /* first 132 bytes only */, int color_type),
1579 PNG_EMPTY);
1580 PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr,
1581 png_colorspacerp colorspace, png_const_charp name,
1582 png_uint_32 profile_length,
1583 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY);
1584 #ifdef PNG_sRGB_SUPPORTED
1585 PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,(
1586 png_const_structrp png_ptr, png_colorspacerp colorspace,
1587 png_const_bytep profile, uLong adler), PNG_EMPTY);
1588 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may
1589 * be zero to indicate that it is not available. It is used, if provided,
1590 * as a fast check on the profile when checking to see if it is sRGB.
1592 #endif
1593 #endif /* iCCP */
1595 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED
1596 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients,
1597 (png_structrp png_ptr), PNG_EMPTY);
1598 /* Set the rgb_to_gray coefficients from the colorspace Y values */
1599 #endif /* READ_RGB_TO_GRAY */
1600 #endif /* COLORSPACE */
1602 /* Added at libpng version 1.4.0 */
1603 PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr,
1604 png_uint_32 width, png_uint_32 height, int bit_depth,
1605 int color_type, int interlace_type, int compression_type,
1606 int filter_type),PNG_EMPTY);
1608 /* Added at libpng version 1.5.10 */
1609 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \
1610 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED)
1611 PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes,
1612 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY);
1613 #endif
1615 #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)
1616 PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr,
1617 png_const_charp name),PNG_NORETURN);
1618 #endif
1620 /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite
1621 * the end. Always leaves the buffer nul terminated. Never errors out (and
1622 * there is no error code.)
1624 PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize,
1625 size_t pos, png_const_charp string),PNG_EMPTY);
1627 /* Various internal functions to handle formatted warning messages, currently
1628 * only implemented for warnings.
1630 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED)
1631 /* Utility to dump an unsigned value into a buffer, given a start pointer and
1632 * and end pointer (which should point just *beyond* the end of the buffer!)
1633 * Returns the pointer to the start of the formatted string. This utility only
1634 * does unsigned values.
1636 PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start,
1637 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY);
1639 /* Convenience macro that takes an array: */
1640 #define PNG_FORMAT_NUMBER(buffer,format,number) \
1641 png_format_number(buffer, buffer + (sizeof buffer), format, number)
1643 /* Suggested size for a number buffer (enough for 64 bits and a sign!) */
1644 #define PNG_NUMBER_BUFFER_SIZE 24
1646 /* These are the integer formats currently supported, the name is formed from
1647 * the standard printf(3) format string.
1649 #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */
1650 #define PNG_NUMBER_FORMAT_02u 2
1651 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */
1652 #define PNG_NUMBER_FORMAT_02d 2
1653 #define PNG_NUMBER_FORMAT_x 3
1654 #define PNG_NUMBER_FORMAT_02x 4
1655 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */
1656 #endif
1658 #ifdef PNG_WARNINGS_SUPPORTED
1659 /* New defines and members adding in libpng-1.5.4 */
1660 # define PNG_WARNING_PARAMETER_SIZE 32
1661 # define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */
1663 /* An l-value of this type has to be passed to the APIs below to cache the
1664 * values of the parameters to a formatted warning message.
1666 typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][
1667 PNG_WARNING_PARAMETER_SIZE];
1669 PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p,
1670 int number, png_const_charp string),PNG_EMPTY);
1671 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
1672 * including the trailing '\0'.
1674 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned,
1675 (png_warning_parameters p, int number, int format, png_alloc_size_t value),
1676 PNG_EMPTY);
1677 /* Use png_alloc_size_t because it is an unsigned type as big as any we
1678 * need to output. Use the following for a signed value.
1680 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed,
1681 (png_warning_parameters p, int number, int format, png_int_32 value),
1682 PNG_EMPTY);
1684 PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr,
1685 png_warning_parameters p, png_const_charp message),PNG_EMPTY);
1686 /* 'message' follows the X/Open approach of using @1, @2 to insert
1687 * parameters previously supplied using the above functions. Errors in
1688 * specifying the parameters will simply result in garbage substitutions.
1690 #endif
1692 #ifdef PNG_BENIGN_ERRORS_SUPPORTED
1693 /* Application errors (new in 1.6); use these functions (declared below) for
1694 * errors in the parameters or order of API function calls on read. The
1695 * 'warning' should be used for an error that can be handled completely; the
1696 * 'error' for one which can be handled safely but which may lose application
1697 * information or settings.
1699 * By default these both result in a png_error call prior to release, while in a
1700 * released version the 'warning' is just a warning. However if the application
1701 * explicitly disables benign errors (explicitly permitting the code to lose
1702 * information) they both turn into warnings.
1704 * If benign errors aren't supported they end up as the corresponding base call
1705 * (png_warning or png_error.)
1707 PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr,
1708 png_const_charp message),PNG_EMPTY);
1709 /* The application provided invalid parameters to an API function or called
1710 * an API function at the wrong time, libpng can completely recover.
1713 PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr,
1714 png_const_charp message),PNG_EMPTY);
1715 /* As above but libpng will ignore the call, or attempt some other partial
1716 * recovery from the error.
1718 #else
1719 # define png_app_warning(pp,s) png_warning(pp,s)
1720 # define png_app_error(pp,s) png_error(pp,s)
1721 #endif
1723 PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr,
1724 png_const_charp message, int error),PNG_EMPTY);
1725 /* Report a recoverable issue in chunk data. On read this is used to report
1726 * a problem found while reading a particular chunk and the
1727 * png_chunk_benign_error or png_chunk_warning function is used as
1728 * appropriate. On write this is used to report an error that comes from
1729 * data set via an application call to a png_set_ API and png_app_error or
1730 * png_app_warning is used as appropriate.
1732 * The 'error' parameter must have one of the following values:
1734 #define PNG_CHUNK_WARNING 0 /* never an error */
1735 #define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */
1736 #define PNG_CHUNK_ERROR 2 /* always an error */
1738 /* ASCII to FP interfaces, currently only implemented if sCAL
1739 * support is required.
1741 #if defined(PNG_sCAL_SUPPORTED)
1742 /* MAX_DIGITS is actually the maximum number of characters in an sCAL
1743 * width or height, derived from the precision (number of significant
1744 * digits - a build time settable option) and assumptions about the
1745 * maximum ridiculous exponent.
1747 #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/)
1749 #ifdef PNG_FLOATING_POINT_SUPPORTED
1750 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr,
1751 png_charp ascii, png_size_t size, double fp, unsigned int precision),
1752 PNG_EMPTY);
1753 #endif /* FLOATING_POINT */
1755 #ifdef PNG_FIXED_POINT_SUPPORTED
1756 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr,
1757 png_charp ascii, png_size_t size, png_fixed_point fp),PNG_EMPTY);
1758 #endif /* FIXED_POINT */
1759 #endif /* sCAL */
1761 #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED)
1762 /* An internal API to validate the format of a floating point number.
1763 * The result is the index of the next character. If the number is
1764 * not valid it will be the index of a character in the supposed number.
1766 * The format of a number is defined in the PNG extensions specification
1767 * and this API is strictly conformant to that spec, not anyone elses!
1769 * The format as a regular expression is:
1771 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)?
1773 * or:
1775 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)?
1777 * The complexity is that either integer or fraction must be present and the
1778 * fraction is permitted to have no digits only if the integer is present.
1780 * NOTE: The dangling E problem.
1781 * There is a PNG valid floating point number in the following:
1783 * PNG floating point numbers are not greedy.
1785 * Working this out requires *TWO* character lookahead (because of the
1786 * sign), the parser does not do this - it will fail at the 'r' - this
1787 * doesn't matter for PNG sCAL chunk values, but it requires more care
1788 * if the value were ever to be embedded in something more complex. Use
1789 * ANSI-C strtod if you need the lookahead.
1791 /* State table for the parser. */
1792 #define PNG_FP_INTEGER 0 /* before or in integer */
1793 #define PNG_FP_FRACTION 1 /* before or in fraction */
1794 #define PNG_FP_EXPONENT 2 /* before or in exponent */
1795 #define PNG_FP_STATE 3 /* mask for the above */
1796 #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */
1797 #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */
1798 #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */
1799 #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */
1800 #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */
1802 /* These three values don't affect the parser. They are set but not used.
1804 #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */
1805 #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */
1806 #define PNG_FP_NONZERO 256 /* A non-zero value */
1807 #define PNG_FP_STICKY 448 /* The above three flags */
1809 /* This is available for the caller to store in 'state' if required. Do not
1810 * call the parser after setting it (the parser sometimes clears it.)
1812 #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */
1814 /* Result codes for the parser (boolean - true meants ok, false means
1815 * not ok yet.)
1817 #define PNG_FP_MAYBE 0 /* The number may be valid in the future */
1818 #define PNG_FP_OK 1 /* The number is valid */
1820 /* Tests on the sticky non-zero and negative flags. To pass these checks
1821 * the state must also indicate that the whole number is valid - this is
1822 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this
1823 * is equivalent to PNG_FP_OK above.)
1825 #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO)
1826 /* NZ_MASK: the string is valid and a non-zero negative value */
1827 #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO)
1828 /* Z MASK: the string is valid and a non-zero value. */
1829 /* PNG_FP_SAW_DIGIT: the string is valid. */
1830 #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT)
1831 #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK)
1832 #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK)
1834 /* The actual parser. This can be called repeatedly. It updates
1835 * the index into the string and the state variable (which must
1836 * be initialized to 0). It returns a result code, as above. There
1837 * is no point calling the parser any more if it fails to advance to
1838 * the end of the string - it is stuck on an invalid character (or
1839 * terminated by '\0').
1841 * Note that the pointer will consume an E or even an E+ and then leave
1842 * a 'maybe' state even though a preceding integer.fraction is valid.
1843 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was
1844 * a valid number. It's possible to recover from this by calling
1845 * the parser again (from the start, with state 0) but with a string
1846 * that omits the last character (i.e. set the size to the index of
1847 * the problem character.) This has not been tested within libpng.
1849 PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string,
1850 png_size_t size, int *statep, png_size_tp whereami),PNG_EMPTY);
1852 /* This is the same but it checks a complete string and returns true
1853 * only if it just contains a floating point number. As of 1.5.4 this
1854 * function also returns the state at the end of parsing the number if
1855 * it was valid (otherwise it returns 0.) This can be used for testing
1856 * for negative or zero values using the sticky flag.
1858 PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string,
1859 png_size_t size),PNG_EMPTY);
1860 #endif /* pCAL || sCAL */
1862 #if defined(PNG_READ_GAMMA_SUPPORTED) ||\
1863 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED)
1864 /* Added at libpng version 1.5.0 */
1865 /* This is a utility to provide a*times/div (rounded) and indicate
1866 * if there is an overflow. The result is a boolean - false (0)
1867 * for overflow, true (1) if no overflow, in which case *res
1868 * holds the result.
1870 PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a,
1871 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY);
1872 #endif
1874 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED)
1875 /* Same deal, but issue a warning on overflow and return 0. */
1876 PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn,
1877 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by,
1878 png_int_32 divided_by),PNG_EMPTY);
1879 #endif
1881 #ifdef PNG_GAMMA_SUPPORTED
1882 /* Calculate a reciprocal - used for gamma values. This returns
1883 * 0 if the argument is 0 in order to maintain an undefined value;
1884 * there are no warnings.
1886 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a),
1887 PNG_EMPTY);
1889 #ifdef PNG_READ_GAMMA_SUPPORTED
1890 /* The same but gives a reciprocal of the product of two fixed point
1891 * values. Accuracy is suitable for gamma calculations but this is
1892 * not exact - use png_muldiv for that. Only required at present on read.
1894 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a,
1895 png_fixed_point b),PNG_EMPTY);
1896 #endif
1898 /* Return true if the gamma value is significantly different from 1.0 */
1899 PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value),
1900 PNG_EMPTY);
1901 #endif
1903 #ifdef PNG_READ_GAMMA_SUPPORTED
1904 /* Internal fixed point gamma correction. These APIs are called as
1905 * required to convert single values - they don't need to be fast,
1906 * they are not used when processing image pixel values.
1908 * While the input is an 'unsigned' value it must actually be the
1909 * correct bit value - 0..255 or 0..65535 as required.
1911 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr,
1912 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY);
1913 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value,
1914 png_fixed_point gamma_value),PNG_EMPTY);
1915 PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value,
1916 png_fixed_point gamma_value),PNG_EMPTY);
1917 PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr),
1918 PNG_EMPTY);
1919 PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr,
1920 int bit_depth),PNG_EMPTY);
1921 #endif
1923 /* SIMPLIFIED READ/WRITE SUPPORT */
1924 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\
1925 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED)
1926 /* The internal structure that png_image::opaque points to. */
1927 typedef struct png_control
1929 png_structp png_ptr;
1930 png_infop info_ptr;
1931 png_voidp error_buf; /* Always a jmp_buf at present. */
1933 png_const_bytep memory; /* Memory buffer. */
1934 png_size_t size; /* Size of the memory buffer. */
1936 unsigned int for_write :1; /* Otherwise it is a read structure */
1937 unsigned int owned_file :1; /* We own the file in io_ptr */
1938 } png_control;
1940 /* Return the pointer to the jmp_buf from a png_control: necessary because C
1941 * does not reveal the type of the elements of jmp_buf.
1943 #ifdef __cplusplus
1944 # define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0])
1945 #else
1946 # define png_control_jmp_buf(pc) ((pc)->error_buf)
1947 #endif
1949 /* Utility to safely execute a piece of libpng code catching and logging any
1950 * errors that might occur. Returns true on success, false on failure (either
1951 * of the function or as a result of a png_error.)
1953 PNG_INTERNAL_FUNCTION(void,png_safe_error,(png_structp png_ptr,
1954 png_const_charp error_message),PNG_NORETURN);
1956 #ifdef PNG_WARNINGS_SUPPORTED
1957 PNG_INTERNAL_FUNCTION(void,png_safe_warning,(png_structp png_ptr,
1958 png_const_charp warning_message),PNG_EMPTY);
1959 #else
1960 # define png_safe_warning 0/*dummy argument*/
1961 #endif
1963 PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image,
1964 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY);
1966 /* Utility to log an error; this also cleans up the png_image; the function
1967 * always returns 0 (false).
1969 PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image,
1970 png_const_charp error_message),PNG_EMPTY);
1972 #ifndef PNG_SIMPLIFIED_READ_SUPPORTED
1973 /* png_image_free is used by the write code but not exported */
1974 PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY);
1975 #endif /* !SIMPLIFIED_READ */
1977 #endif /* SIMPLIFIED READ/WRITE */
1979 /* These are initialization functions for hardware specific PNG filter
1980 * optimizations; list these here then select the appropriate one at compile
1981 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined
1982 * the generic code is used.
1984 #ifdef PNG_FILTER_OPTIMIZATIONS
1985 PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr,
1986 unsigned int bpp), PNG_EMPTY);
1987 /* Just declare the optimization that will be used */
1988 #else
1989 /* List *all* the possible optimizations here - this branch is required if
1990 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in
1991 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing.
1993 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon,
1994 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY);
1995 #endif
1997 /* Maintainer: Put new private prototypes here ^ */
1999 #include "pngdebug.h"
2001 #ifdef __cplusplus
2003 #endif
2005 #endif /* PNG_VERSION_INFO_ONLY */
2006 #endif /* PNGPRIV_H */