1 2 /* pngpriv.h - private declarations for use inside libpng 3 * 4 * For conditions of distribution and use, see copyright notice in png.h 5 * Copyright (c) 1998-2014 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 * Last changed in libpng 1.6.10 [March 6, 2014] 10 * 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 14 */ 15 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. 23 */ 24 25 #ifndef PNGPRIV_H 26 #define PNGPRIV_H 27 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. 31 * 32 * Feature Test Macros must be defined before any system header is included (see 33 * POSIX 1003.1 2.8.2 "POSIX Symbols." 34 * 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.) 39 */ 40 #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */ 41 42 #ifndef PNG_VERSION_INFO_ONLY 43 /* Standard library headers not required by png.h: */ 44 # include <stdlib.h> 45 # include <string.h> 46 #endif 47 48 #define PNGLIB_BUILD /*libpng is being built, not used*/ 49 50 /* If HAVE_CONFIG_H is defined during the build then the build system must 51 * provide an appropriate "config.h" file on the include path. The header file 52 * must provide definitions as required below (search for "HAVE_CONFIG_H"); 53 * see configure.ac for more details of the requirements. The macro 54 * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on 55 * 'configure'; define this macro to prevent the configure build including the 56 * configure generated config.h. Libpng is expected to compile without *any* 57 * special build system support on a reasonably ANSI-C compliant system. 58 */ 59 #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H) 60 # include <config.h> 61 62 /* Pick up the definition of 'restrict' from config.h if it was read: */ 63 # define PNG_RESTRICT restrict 64 #endif 65 66 /* To support symbol prefixing it is necessary to know *before* including png.h 67 * whether the fixed point (and maybe other) APIs are exported, because if they 68 * are not internal definitions may be required. This is handled below just 69 * before png.h is included, but load the configuration now if it is available. 70 */ 71 #ifndef PNGLCONF_H 72 # include "pnglibconf.h" 73 #endif 74 75 /* Local renames may change non-exported API functions from png.h */ 76 #if defined(PNG_PREFIX) && !defined(PNGPREFIX_H) 77 # include "pngprefix.h" 78 #endif 79 80 #ifdef PNG_USER_CONFIG 81 # include "pngusr.h" 82 /* These should have been defined in pngusr.h */ 83 # ifndef PNG_USER_PRIVATEBUILD 84 # define PNG_USER_PRIVATEBUILD "Custom libpng build" 85 # endif 86 # ifndef PNG_USER_DLLFNAME_POSTFIX 87 # define PNG_USER_DLLFNAME_POSTFIX "Cb" 88 # endif 89 #endif 90 91 /* Compile time options. 92 * ===================== 93 * In a multi-arch build the compiler may compile the code several times for the 94 * same object module, producing different binaries for different architectures. 95 * When this happens configure-time setting of the target host options cannot be 96 * done and this interferes with the handling of the ARM NEON optimizations, and 97 * possibly other similar optimizations. Put additional tests here; in general 98 * this is needed when the same option can be changed at both compile time and 99 * run time depending on the target OS (i.e. iOS vs Android.) 100 * 101 * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because 102 * this is not possible with certain compilers (Oracle SUN OS CC), as a result 103 * it is necessary to ensure that all extern functions that *might* be used 104 * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__ 105 * below is one example of this behavior because it is controlled by the 106 * presence or not of -mfpu=neon on the GCC command line, it is possible to do 107 * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely 108 * do this. 109 */ 110 #ifndef PNG_ARM_NEON_OPT 111 /* ARM NEON optimizations are being controlled by the compiler settings, 112 * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon 113 * with GCC) then the compiler will define __ARM_NEON__ and we can rely 114 * unconditionally on NEON instructions not crashing, otherwise we must 115 * disable use of NEON instructions. 116 * 117 * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they 118 * can only be turned on automatically if that is supported too. If 119 * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail 120 * to compile with an appropriate #error if ALIGNED_MEMORY has been turned 121 * off. 122 * 123 * Note that gcc-4.9 defines __ARM_NEON instead of __ARM_NEON__, so we 124 * check both variants. 125 */ 126 # if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \ 127 defined(PNG_ALIGNED_MEMORY_SUPPORTED) 128 # define PNG_ARM_NEON_OPT 2 129 # else 130 # define PNG_ARM_NEON_OPT 0 131 # endif 132 #endif 133 134 #if PNG_ARM_NEON_OPT > 0 135 /* NEON optimizations are to be at least considered by libpng, so enable the 136 * callbacks to do this. 137 */ 138 # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon 139 140 /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used 141 * if possible - if __ARM_NEON__ is set and the compiler version is not known 142 * to be broken. This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can 143 * be: 144 * 145 * 1 The intrinsics code (the default with __ARM_NEON__) 146 * 2 The hand coded assembler (the default without __ARM_NEON__) 147 * 148 * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however 149 * this is *NOT* supported and may cease to work even after a minor revision 150 * to libpng. It *is* valid to do this for testing purposes, e.g. speed 151 * testing or a new compiler, but the results should be communicated to the 152 * libpng implementation list for incorporation in the next minor release. 153 */ 154 # ifndef PNG_ARM_NEON_IMPLEMENTATION 155 # if defined(__ARM_NEON__) || defined(__ARM_NEON) 156 # if defined(__clang__) 157 /* At present it is unknown by the libpng developers which versions 158 * of clang support the intrinsics, however some or perhaps all 159 * versions do not work with the assembler so this may be 160 * irrelevant, so just use the default (do nothing here.) 161 */ 162 # elif defined(__GNUC__) 163 /* GCC 4.5.4 NEON support is known to be broken. 4.6.3 is known to 164 * work, so if this *is* GCC, or G++, look for a version >4.5 165 */ 166 # if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6) 167 # define PNG_ARM_NEON_IMPLEMENTATION 2 168 # endif /* no GNUC support */ 169 # endif /* __GNUC__ */ 170 # else /* !defined __ARM_NEON__ */ 171 /* The 'intrinsics' code simply won't compile without this -mfpu=neon: 172 */ 173 # define PNG_ARM_NEON_IMPLEMENTATION 2 174 # endif /* __ARM_NEON__ */ 175 # endif /* !defined PNG_ARM_NEON_IMPLEMENTATION */ 176 177 # ifndef PNG_ARM_NEON_IMPLEMENTATION 178 /* Use the intrinsics code by default. */ 179 # define PNG_ARM_NEON_IMPLEMENTATION 1 180 # endif 181 #endif /* PNG_ARM_NEON_OPT > 0 */ 182 183 /* Is this a build of a DLL where compilation of the object modules requires 184 * different preprocessor settings to those required for a simple library? If 185 * so PNG_BUILD_DLL must be set. 186 * 187 * If libpng is used inside a DLL but that DLL does not export the libpng APIs 188 * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a 189 * static library of libpng then link the DLL against that. 190 */ 191 #ifndef PNG_BUILD_DLL 192 # ifdef DLL_EXPORT 193 /* This is set by libtool when files are compiled for a DLL; libtool 194 * always compiles twice, even on systems where it isn't necessary. Set 195 * PNG_BUILD_DLL in case it is necessary: 196 */ 197 # define PNG_BUILD_DLL 198 # else 199 # ifdef _WINDLL 200 /* This is set by the Microsoft Visual Studio IDE in projects that 201 * build a DLL. It can't easily be removed from those projects (it 202 * isn't visible in the Visual Studio UI) so it is a fairly reliable 203 * indication that PNG_IMPEXP needs to be set to the DLL export 204 * attributes. 205 */ 206 # define PNG_BUILD_DLL 207 # else 208 # ifdef __DLL__ 209 /* This is set by the Borland C system when compiling for a DLL 210 * (as above.) 211 */ 212 # define PNG_BUILD_DLL 213 # else 214 /* Add additional compiler cases here. */ 215 # endif 216 # endif 217 # endif 218 #endif /* Setting PNG_BUILD_DLL if required */ 219 220 /* See pngconf.h for more details: the builder of the library may set this on 221 * the command line to the right thing for the specific compilation system or it 222 * may be automagically set above (at present we know of no system where it does 223 * need to be set on the command line.) 224 * 225 * PNG_IMPEXP must be set here when building the library to prevent pngconf.h 226 * setting it to the "import" setting for a DLL build. 227 */ 228 #ifndef PNG_IMPEXP 229 # ifdef PNG_BUILD_DLL 230 # define PNG_IMPEXP PNG_DLL_EXPORT 231 # else 232 /* Not building a DLL, or the DLL doesn't require specific export 233 * definitions. 234 */ 235 # define PNG_IMPEXP 236 # endif 237 #endif 238 239 /* No warnings for private or deprecated functions in the build: */ 240 #ifndef PNG_DEPRECATED 241 # define PNG_DEPRECATED 242 #endif 243 #ifndef PNG_PRIVATE 244 # define PNG_PRIVATE 245 #endif 246 247 /* Symbol preprocessing support. 248 * 249 * To enable listing global, but internal, symbols the following macros should 250 * always be used to declare an extern data or function object in this file. 251 */ 252 #ifndef PNG_INTERNAL_DATA 253 # define PNG_INTERNAL_DATA(type, name, array) extern type name array 254 #endif 255 256 #ifndef PNG_INTERNAL_FUNCTION 257 # define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\ 258 extern PNG_FUNCTION(type, name, args, PNG_EMPTY attributes) 259 #endif 260 261 #ifndef PNG_INTERNAL_CALLBACK 262 # define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\ 263 extern PNG_FUNCTION(type, (PNGCBAPI name), args, PNG_EMPTY attributes) 264 #endif 265 266 /* If floating or fixed point APIs are disabled they may still be compiled 267 * internally. To handle this make sure they are declared as the appropriate 268 * internal extern function (otherwise the symbol prefixing stuff won't work and 269 * the functions will be used without definitions.) 270 * 271 * NOTE: although all the API functions are declared here they are not all 272 * actually built! Because the declarations are still made it is necessary to 273 * fake out types that they depend on. 274 */ 275 #ifndef PNG_FP_EXPORT 276 # ifndef PNG_FLOATING_POINT_SUPPORTED 277 # define PNG_FP_EXPORT(ordinal, type, name, args)\ 278 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY); 279 # ifndef PNG_VERSION_INFO_ONLY 280 typedef struct png_incomplete png_double; 281 typedef png_double* png_doublep; 282 typedef const png_double* png_const_doublep; 283 typedef png_double** png_doublepp; 284 # endif 285 # endif 286 #endif 287 #ifndef PNG_FIXED_EXPORT 288 # ifndef PNG_FIXED_POINT_SUPPORTED 289 # define PNG_FIXED_EXPORT(ordinal, type, name, args)\ 290 PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY); 291 # endif 292 #endif 293 294 #include "png.h" 295 296 /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */ 297 #ifndef PNG_DLL_EXPORT 298 # define PNG_DLL_EXPORT 299 #endif 300 301 /* SECURITY and SAFETY: 302 * 303 * By default libpng is built without any internal limits on image size, 304 * individual heap (png_malloc) allocations or the total amount of memory used. 305 * If PNG_SAFE_LIMITS_SUPPORTED is defined, however, the limits below are used 306 * (unless individually overridden). These limits are believed to be fairly 307 * safe, but builders of secure systems should verify the values against the 308 * real system capabilities. 309 */ 310 #ifdef PNG_SAFE_LIMITS_SUPPORTED 311 /* 'safe' limits */ 312 # ifndef PNG_USER_WIDTH_MAX 313 # define PNG_USER_WIDTH_MAX 1000000 314 # endif 315 # ifndef PNG_USER_HEIGHT_MAX 316 # define PNG_USER_HEIGHT_MAX 1000000 317 # endif 318 # ifndef PNG_USER_CHUNK_CACHE_MAX 319 # define PNG_USER_CHUNK_CACHE_MAX 128 320 # endif 321 # ifndef PNG_USER_CHUNK_MALLOC_MAX 322 # define PNG_USER_CHUNK_MALLOC_MAX 8000000 323 # endif 324 #else 325 /* values for no limits */ 326 # ifndef PNG_USER_WIDTH_MAX 327 # define PNG_USER_WIDTH_MAX 0x7fffffff 328 # endif 329 # ifndef PNG_USER_HEIGHT_MAX 330 # define PNG_USER_HEIGHT_MAX 0x7fffffff 331 # endif 332 # ifndef PNG_USER_CHUNK_CACHE_MAX 333 # define PNG_USER_CHUNK_CACHE_MAX 0 334 # endif 335 # ifndef PNG_USER_CHUNK_MALLOC_MAX 336 # define PNG_USER_CHUNK_MALLOC_MAX 0 337 # endif 338 #endif 339 340 /* Moved to pngpriv.h at libpng-1.5.0 */ 341 /* NOTE: some of these may have been used in external applications as 342 * these definitions were exposed in pngconf.h prior to 1.5. 343 */ 344 345 /* If you are running on a machine where you cannot allocate more 346 * than 64K of memory at once, uncomment this. While libpng will not 347 * normally need that much memory in a chunk (unless you load up a very 348 * large file), zlib needs to know how big of a chunk it can use, and 349 * libpng thus makes sure to check any memory allocation to verify it 350 * will fit into memory. 351 * 352 * zlib provides 'MAXSEG_64K' which, if defined, indicates the 353 * same limit and pngconf.h (already included) sets the limit 354 * if certain operating systems are detected. 355 */ 356 #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K) 357 # define PNG_MAX_MALLOC_64K 358 #endif 359 360 #ifndef PNG_UNUSED 361 /* Unused formal parameter warnings are silenced using the following macro 362 * which is expected to have no bad effects on performance (optimizing 363 * compilers will probably remove it entirely). Note that if you replace 364 * it with something other than whitespace, you must include the terminating 365 * semicolon. 366 */ 367 # define PNG_UNUSED(param) (void)param; 368 #endif 369 370 /* Just a little check that someone hasn't tried to define something 371 * contradictory. 372 */ 373 #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K) 374 # undef PNG_ZBUF_SIZE 375 # define PNG_ZBUF_SIZE 65536L 376 #endif 377 378 /* If warnings or errors are turned off the code is disabled or redirected here. 379 * From 1.5.4 functions have been added to allow very limited formatting of 380 * error and warning messages - this code will also be disabled here. 381 */ 382 #ifdef PNG_WARNINGS_SUPPORTED 383 # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p; 384 #else 385 # define png_warning_parameter(p,number,string) ((void)0) 386 # define png_warning_parameter_unsigned(p,number,format,value) ((void)0) 387 # define png_warning_parameter_signed(p,number,format,value) ((void)0) 388 # define png_formatted_warning(pp,p,message) ((void)(pp)) 389 # define PNG_WARNING_PARAMETERS(p) 390 #endif 391 #ifndef PNG_ERROR_TEXT_SUPPORTED 392 # define png_fixed_error(s1,s2) png_err(s1) 393 #endif 394 395 /* C allows up-casts from (void*) to any pointer and (const void*) to any 396 * pointer to a const object. C++ regards this as a type error and requires an 397 * explicit, static, cast and provides the static_cast<> rune to ensure that 398 * const is not cast away. 399 */ 400 #ifdef __cplusplus 401 # define png_voidcast(type, value) static_cast<type>(value) 402 # define png_constcast(type, value) const_cast<type>(value) 403 # define png_aligncast(type, value) \ 404 static_cast<type>(static_cast<void*>(value)) 405 # define png_aligncastconst(type, value) \ 406 static_cast<type>(static_cast<const void*>(value)) 407 #else 408 # define png_voidcast(type, value) (value) 409 # define png_constcast(type, value) ((type)(value)) 410 # define png_aligncast(type, value) ((void*)(value)) 411 # define png_aligncastconst(type, value) ((const void*)(value)) 412 #endif /* __cplusplus */ 413 414 /* Some fixed point APIs are still required even if not exported because 415 * they get used by the corresponding floating point APIs. This magic 416 * deals with this: 417 */ 418 #ifdef PNG_FIXED_POINT_SUPPORTED 419 # define PNGFAPI PNGAPI 420 #else 421 # define PNGFAPI /* PRIVATE */ 422 #endif 423 424 #ifndef PNG_VERSION_INFO_ONLY 425 /* Other defines specific to compilers can go here. Try to keep 426 * them inside an appropriate ifdef/endif pair for portability. 427 */ 428 #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\ 429 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) 430 /* png.c requires the following ANSI-C constants if the conversion of 431 * floating point to ASCII is implemented therein: 432 * 433 * DBL_DIG Maximum number of decimal digits (can be set to any constant) 434 * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value) 435 * DBL_MAX Maximum floating point number (can be set to an arbitrary value) 436 */ 437 # include <float.h> 438 439 # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \ 440 defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC) 441 /* We need to check that <math.h> hasn't already been included earlier 442 * as it seems it doesn't agree with <fp.h>, yet we should really use 443 * <fp.h> if possible. 444 */ 445 # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__) 446 # include <fp.h> 447 # endif 448 # else 449 # include <math.h> 450 # endif 451 # if defined(_AMIGA) && defined(__SASC) && defined(_M68881) 452 /* Amiga SAS/C: We must include builtin FPU functions when compiling using 453 * MATH=68881 454 */ 455 # include <m68881.h> 456 # endif 457 #endif 458 459 /* This provides the non-ANSI (far) memory allocation routines. */ 460 #if defined(__TURBOC__) && defined(__MSDOS__) 461 # include <mem.h> 462 # include <alloc.h> 463 #endif 464 465 #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \ 466 defined(_WIN32) || defined(__WIN32__) 467 # include <windows.h> /* defines _WINDOWS_ macro */ 468 #endif 469 #endif /* PNG_VERSION_INFO_ONLY */ 470 471 /* Moved here around 1.5.0beta36 from pngconf.h */ 472 /* Users may want to use these so they are not private. Any library 473 * functions that are passed far data must be model-independent. 474 */ 475 476 /* Memory model/platform independent fns */ 477 #ifndef PNG_ABORT 478 # ifdef _WINDOWS_ 479 # define PNG_ABORT() ExitProcess(0) 480 # else 481 # define PNG_ABORT() abort() 482 # endif 483 #endif 484 485 /* These macros may need to be architecture dependent. */ 486 #define PNG_ALIGN_NONE 0 /* do not use data alignment */ 487 #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */ 488 #ifdef offsetof 489 # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */ 490 #else 491 # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */ 492 #endif 493 #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */ 494 495 #ifndef PNG_ALIGN_TYPE 496 /* Default to using aligned access optimizations and requiring alignment to a 497 * multiple of the data type size. Override in a compiler specific fashion 498 * if necessary by inserting tests here: 499 */ 500 # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE 501 #endif 502 503 #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE 504 /* This is used because in some compiler implementations non-aligned 505 * structure members are supported, so the offsetof approach below fails. 506 * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access 507 * is good for performance. Do not do this unless you have tested the result 508 * and understand it. 509 */ 510 # define png_alignof(type) (sizeof (type)) 511 #else 512 # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET 513 # define png_alignof(type) offsetof(struct{char c; type t;}, t) 514 # else 515 # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS 516 # define png_alignof(type) (1) 517 # endif 518 /* Else leave png_alignof undefined to prevent use thereof */ 519 # endif 520 #endif 521 522 /* This implicitly assumes alignment is always to a power of 2. */ 523 #ifdef png_alignof 524 # define png_isaligned(ptr, type)\ 525 ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0) 526 #else 527 # define png_isaligned(ptr, type) 0 528 #endif 529 530 /* End of memory model/platform independent support */ 531 /* End of 1.5.0beta36 move from pngconf.h */ 532 533 /* CONSTANTS and UTILITY MACROS 534 * These are used internally by libpng and not exposed in the API 535 */ 536 537 /* Various modes of operation. Note that after an init, mode is set to 538 * zero automatically when the structure is created. Three of these 539 * are defined in png.h because they need to be visible to applications 540 * that call png_set_unknown_chunk(). 541 */ 542 /* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */ 543 /* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */ 544 #define PNG_HAVE_IDAT 0x04 545 /* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */ 546 #define PNG_HAVE_IEND 0x10 547 /* 0x20 (unused) */ 548 /* 0x40 (unused) */ 549 /* 0x80 (unused) */ 550 #define PNG_HAVE_CHUNK_HEADER 0x100 551 #define PNG_WROTE_tIME 0x200 552 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400 553 #define PNG_BACKGROUND_IS_GRAY 0x800 554 #define PNG_HAVE_PNG_SIGNATURE 0x1000 555 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */ 556 /* 0x4000 (unused) */ 557 #define PNG_IS_READ_STRUCT 0x8000 /* Else is a write struct */ 558 559 /* Flags for the transformations the PNG library does on the image data */ 560 #define PNG_BGR 0x0001 561 #define PNG_INTERLACE 0x0002 562 #define PNG_PACK 0x0004 563 #define PNG_SHIFT 0x0008 564 #define PNG_SWAP_BYTES 0x0010 565 #define PNG_INVERT_MONO 0x0020 566 #define PNG_QUANTIZE 0x0040 567 #define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */ 568 #define PNG_BACKGROUND_EXPAND 0x0100 569 #define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */ 570 #define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */ 571 #define PNG_RGBA 0x0800 572 #define PNG_EXPAND 0x1000 573 #define PNG_GAMMA 0x2000 574 #define PNG_GRAY_TO_RGB 0x4000 575 #define PNG_FILLER 0x8000 576 #define PNG_PACKSWAP 0x10000 577 #define PNG_SWAP_ALPHA 0x20000 578 #define PNG_STRIP_ALPHA 0x40000 579 #define PNG_INVERT_ALPHA 0x80000 580 #define PNG_USER_TRANSFORM 0x100000 581 #define PNG_RGB_TO_GRAY_ERR 0x200000 582 #define PNG_RGB_TO_GRAY_WARN 0x400000 583 #define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */ 584 #define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */ 585 #define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */ 586 #define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */ 587 #define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */ 588 /* 0x8000000 unused */ 589 /* 0x10000000 unused */ 590 /* 0x20000000 unused */ 591 /* 0x40000000 unused */ 592 /* Flags for png_create_struct */ 593 #define PNG_STRUCT_PNG 0x0001 594 #define PNG_STRUCT_INFO 0x0002 595 596 /* Scaling factor for filter heuristic weighting calculations */ 597 #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT)) 598 #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT)) 599 600 /* Flags for the png_ptr->flags rather than declaring a byte for each one */ 601 #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001 602 #define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002 /* Added to libpng-1.6.0 */ 603 /* 0x0004 unused */ 604 #define PNG_FLAG_ZSTREAM_ENDED 0x0008 /* Added to libpng-1.6.0 */ 605 /* 0x0010 unused */ 606 /* 0x0020 unused */ 607 #define PNG_FLAG_ROW_INIT 0x0040 608 #define PNG_FLAG_FILLER_AFTER 0x0080 609 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100 610 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200 611 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400 612 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800 613 #define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */ 614 #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */ 615 #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */ 616 /* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000 */ 617 /* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000 */ 618 #define PNG_FLAG_LIBRARY_MISMATCH 0x20000 619 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000 620 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000 621 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000 /* Added to libpng-1.4.0 */ 622 #define PNG_FLAG_APP_WARNINGS_WARN 0x200000 /* Added to libpng-1.6.0 */ 623 #define PNG_FLAG_APP_ERRORS_WARN 0x400000 /* Added to libpng-1.6.0 */ 624 /* 0x800000 unused */ 625 /* 0x1000000 unused */ 626 /* 0x2000000 unused */ 627 /* 0x4000000 unused */ 628 /* 0x8000000 unused */ 629 /* 0x10000000 unused */ 630 /* 0x20000000 unused */ 631 /* 0x40000000 unused */ 632 633 #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \ 634 PNG_FLAG_CRC_ANCILLARY_NOWARN) 635 636 #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \ 637 PNG_FLAG_CRC_CRITICAL_IGNORE) 638 639 #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \ 640 PNG_FLAG_CRC_CRITICAL_MASK) 641 642 /* Save typing and make code easier to understand */ 643 644 #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \ 645 abs((int)((c1).green) - (int)((c2).green)) + \ 646 abs((int)((c1).blue) - (int)((c2).blue))) 647 648 /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255 649 * by dividing by 257 *with rounding*. This macro is exact for the given range. 650 * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the 651 * macro were established by experiment (modifying the added value). The macro 652 * has a second variant that takes a value already scaled by 255 and divides by 653 * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it 654 * only gives off-by-one errors and only for 0.5% (1 in 200) of the values. 655 */ 656 #define PNG_DIV65535(v24) (((v24) + 32895) >> 16) 657 #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255) 658 659 /* Added to libpng-1.2.6 JB */ 660 #define PNG_ROWBYTES(pixel_bits, width) \ 661 ((pixel_bits) >= 8 ? \ 662 ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \ 663 (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) ) 664 665 /* PNG_OUT_OF_RANGE returns true if value is outside the range 666 * ideal-delta..ideal+delta. Each argument is evaluated twice. 667 * "ideal" and "delta" should be constants, normally simple 668 * integers, "value" a variable. Added to libpng-1.2.6 JB 669 */ 670 #define PNG_OUT_OF_RANGE(value, ideal, delta) \ 671 ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) ) 672 673 /* Conversions between fixed and floating point, only defined if 674 * required (to make sure the code doesn't accidentally use float 675 * when it is supposedly disabled.) 676 */ 677 #ifdef PNG_FLOATING_POINT_SUPPORTED 678 /* The floating point conversion can't overflow, though it can and 679 * does lose accuracy relative to the original fixed point value. 680 * In practice this doesn't matter because png_fixed_point only 681 * stores numbers with very low precision. The png_ptr and s 682 * arguments are unused by default but are there in case error 683 * checking becomes a requirement. 684 */ 685 #define png_float(png_ptr, fixed, s) (.00001 * (fixed)) 686 687 /* The fixed point conversion performs range checking and evaluates 688 * its argument multiple times, so must be used with care. The 689 * range checking uses the PNG specification values for a signed 690 * 32 bit fixed point value except that the values are deliberately 691 * rounded-to-zero to an integral value - 21474 (21474.83 is roughly 692 * (2^31-1) * 100000). 's' is a string that describes the value being 693 * converted. 694 * 695 * NOTE: this macro will raise a png_error if the range check fails, 696 * therefore it is normally only appropriate to use this on values 697 * that come from API calls or other sources where an out of range 698 * error indicates a programming error, not a data error! 699 * 700 * NOTE: by default this is off - the macro is not used - because the 701 * function call saves a lot of code. 702 */ 703 #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED 704 #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\ 705 ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0)) 706 #endif 707 /* else the corresponding function is defined below, inside the scope of the 708 * cplusplus test. 709 */ 710 #endif 711 712 /* Constants for known chunk types. If you need to add a chunk, define the name 713 * here. For historical reasons these constants have the form png_<name>; i.e. 714 * the prefix is lower case. Please use decimal values as the parameters to 715 * match the ISO PNG specification and to avoid relying on the C locale 716 * interpretation of character values. 717 * 718 * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values 719 * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string 720 * to be generated if required. 721 * 722 * PNG_32b correctly produces a value shifted by up to 24 bits, even on 723 * architectures where (int) is only 16 bits. 724 */ 725 #define PNG_32b(b,s) ((png_uint_32)(b) << (s)) 726 #define PNG_U32(b1,b2,b3,b4) \ 727 (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0)) 728 729 /* Constants for known chunk types. 730 * 731 * MAINTAINERS: If you need to add a chunk, define the name here. 732 * For historical reasons these constants have the form png_<name>; i.e. 733 * the prefix is lower case. Please use decimal values as the parameters to 734 * match the ISO PNG specification and to avoid relying on the C locale 735 * interpretation of character values. Please keep the list sorted. 736 * 737 * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk 738 * type. In fact the specification does not express chunk types this way, 739 * however using a 32-bit value means that the chunk type can be read from the 740 * stream using exactly the same code as used for a 32-bit unsigned value and 741 * can be examined far more efficiently (using one arithmetic compare). 742 * 743 * Prior to 1.5.6 the chunk type constants were expressed as C strings. The 744 * libpng API still uses strings for 'unknown' chunks and a macro, 745 * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice 746 * that for portable code numeric values must still be used; the string "IHDR" 747 * is not portable and neither is PNG_U32('I', 'H', 'D', 'R'). 748 * 749 * In 1.7.0 the definitions will be made public in png.h to avoid having to 750 * duplicate the same definitions in application code. 751 */ 752 #define png_IDAT PNG_U32( 73, 68, 65, 84) 753 #define png_IEND PNG_U32( 73, 69, 78, 68) 754 #define png_IHDR PNG_U32( 73, 72, 68, 82) 755 #define png_PLTE PNG_U32( 80, 76, 84, 69) 756 #define png_bKGD PNG_U32( 98, 75, 71, 68) 757 #define png_cHRM PNG_U32( 99, 72, 82, 77) 758 #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */ 759 #define png_gAMA PNG_U32(103, 65, 77, 65) 760 #define png_gIFg PNG_U32(103, 73, 70, 103) 761 #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */ 762 #define png_gIFx PNG_U32(103, 73, 70, 120) 763 #define png_hIST PNG_U32(104, 73, 83, 84) 764 #define png_iCCP PNG_U32(105, 67, 67, 80) 765 #define png_iTXt PNG_U32(105, 84, 88, 116) 766 #define png_oFFs PNG_U32(111, 70, 70, 115) 767 #define png_pCAL PNG_U32(112, 67, 65, 76) 768 #define png_pHYs PNG_U32(112, 72, 89, 115) 769 #define png_sBIT PNG_U32(115, 66, 73, 84) 770 #define png_sCAL PNG_U32(115, 67, 65, 76) 771 #define png_sPLT PNG_U32(115, 80, 76, 84) 772 #define png_sRGB PNG_U32(115, 82, 71, 66) 773 #define png_sTER PNG_U32(115, 84, 69, 82) 774 #define png_tEXt PNG_U32(116, 69, 88, 116) 775 #define png_tIME PNG_U32(116, 73, 77, 69) 776 #define png_tRNS PNG_U32(116, 82, 78, 83) 777 #define png_zTXt PNG_U32(122, 84, 88, 116) 778 779 /* The following will work on (signed char*) strings, whereas the get_uint_32 780 * macro will fail on top-bit-set values because of the sign extension. 781 */ 782 #define PNG_CHUNK_FROM_STRING(s)\ 783 PNG_U32(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3]) 784 785 /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is 786 * signed and the argument is a (char[]) This macro will fail miserably on 787 * systems where (char) is more than 8 bits. 788 */ 789 #define PNG_STRING_FROM_CHUNK(s,c)\ 790 (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\ 791 ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c))) 792 793 /* Do the same but terminate with a null character. */ 794 #define PNG_CSTRING_FROM_CHUNK(s,c)\ 795 (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0) 796 797 /* Test on flag values as defined in the spec (section 5.4): */ 798 #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29)) 799 #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c)) 800 #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21)) 801 #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13)) 802 #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5)) 803 804 /* Gamma values (new at libpng-1.5.4): */ 805 #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */ 806 #define PNG_GAMMA_MAC_INVERSE 65909 807 #define PNG_GAMMA_sRGB_INVERSE 45455 808 809 /* Almost everything below is C specific; the #defines above can be used in 810 * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot. 811 */ 812 #ifndef PNG_VERSION_INFO_ONLY 813 814 #include "pngstruct.h" 815 #include "pnginfo.h" 816 817 /* Validate the include paths - the include path used to generate pnglibconf.h 818 * must match that used in the build, or we must be using pnglibconf.h.prebuilt: 819 */ 820 #if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM 821 # error ZLIB_VERNUM != PNG_ZLIB_VERNUM \ 822 "-I (include path) error: see the notes in pngpriv.h" 823 /* This means that when pnglibconf.h was built the copy of zlib.h that it 824 * used is not the same as the one being used here. Because the build of 825 * libpng makes decisions to use inflateInit2 and inflateReset2 based on the 826 * zlib version number and because this affects handling of certain broken 827 * PNG files the -I directives must match. 828 * 829 * The most likely explanation is that you passed a -I in CFLAGS, this will 830 * not work; all the preprocessor directories and in particular all the -I 831 * directives must be in CPPFLAGS. 832 */ 833 #endif 834 835 /* This is used for 16 bit gamma tables -- only the top level pointers are 836 * const; this could be changed: 837 */ 838 typedef const png_uint_16p * png_const_uint_16pp; 839 840 /* Added to libpng-1.5.7: sRGB conversion tables */ 841 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\ 842 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) 843 #ifdef PNG_SIMPLIFIED_READ_SUPPORTED 844 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]); 845 /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value, 846 * 0..65535. This table gives the closest 16-bit answers (no errors). 847 */ 848 #endif 849 850 PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]); 851 PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]); 852 853 #define PNG_sRGB_FROM_LINEAR(linear) ((png_byte)((png_sRGB_base[(linear)>>15] +\ 854 ((((linear)&0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8)) 855 /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB 856 * encoded value with maximum error 0.646365. Note that the input is not a 857 * 16-bit value; it has been multiplied by 255! */ 858 #endif /* PNG_SIMPLIFIED_READ/WRITE */ 859 860 861 /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ 862 #ifdef __cplusplus 863 extern "C" { 864 #endif /* __cplusplus */ 865 866 /* Internal functions; these are not exported from a DLL however because they 867 * are used within several of the C source files they have to be C extern. 868 * 869 * All of these functions must be declared with PNG_INTERNAL_FUNCTION. 870 */ 871 872 /* Zlib support */ 873 #define PNG_UNEXPECTED_ZLIB_RETURN (-7) 874 PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret), 875 PNG_EMPTY); 876 /* Used by the zlib handling functions to ensure that z_stream::msg is always 877 * set before they return. 878 */ 879 880 #ifdef PNG_WRITE_SUPPORTED 881 PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr, 882 png_compression_bufferp *list),PNG_EMPTY); 883 /* Free the buffer list used by the compressed write code. */ 884 #endif 885 886 #if defined(PNG_FLOATING_POINT_SUPPORTED) && \ 887 !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \ 888 (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \ 889 defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \ 890 defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \ 891 (defined(PNG_sCAL_SUPPORTED) && \ 892 defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)) 893 PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr, 894 double fp, png_const_charp text),PNG_EMPTY); 895 #endif 896 897 /* Check the user version string for compatibility, returns false if the version 898 * numbers aren't compatible. 899 */ 900 PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr, 901 png_const_charp user_png_ver),PNG_EMPTY); 902 903 /* Internal base allocator - no messages, NULL on failure to allocate. This 904 * does, however, call the application provided allocator and that could call 905 * png_error (although that would be a bug in the application implementation.) 906 */ 907 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr, 908 png_alloc_size_t size),PNG_ALLOCATED); 909 910 #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\ 911 defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) 912 /* Internal array allocator, outputs no error or warning messages on failure, 913 * just returns NULL. 914 */ 915 PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr, 916 int nelements, size_t element_size),PNG_ALLOCATED); 917 918 /* The same but an existing array is extended by add_elements. This function 919 * also memsets the new elements to 0 and copies the old elements. The old 920 * array is not freed or altered. 921 */ 922 PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr, 923 png_const_voidp array, int old_elements, int add_elements, 924 size_t element_size),PNG_ALLOCATED); 925 #endif /* text, sPLT or unknown chunks */ 926 927 /* Magic to create a struct when there is no struct to call the user supplied 928 * memory allocators. Because error handling has not been set up the memory 929 * handlers can't safely call png_error, but this is an obscure and undocumented 930 * restriction so libpng has to assume that the 'free' handler, at least, might 931 * call png_error. 932 */ 933 PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct, 934 (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, 935 png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn, 936 png_free_ptr free_fn),PNG_ALLOCATED); 937 938 /* Free memory from internal libpng struct */ 939 PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr), 940 PNG_EMPTY); 941 942 /* Free an allocated jmp_buf (always succeeds) */ 943 PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY); 944 945 /* Function to allocate memory for zlib. PNGAPI is disallowed. */ 946 PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size), 947 PNG_ALLOCATED); 948 949 /* Function to free memory for zlib. PNGAPI is disallowed. */ 950 PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY); 951 952 /* Next four functions are used internally as callbacks. PNGCBAPI is required 953 * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to 954 * PNGCBAPI at 1.5.0 955 */ 956 957 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr, 958 png_bytep data, png_size_t length),PNG_EMPTY); 959 960 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED 961 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr, 962 png_bytep buffer, png_size_t length),PNG_EMPTY); 963 #endif 964 965 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr, 966 png_bytep data, png_size_t length),PNG_EMPTY); 967 968 #ifdef PNG_WRITE_FLUSH_SUPPORTED 969 # ifdef PNG_STDIO_SUPPORTED 970 PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr), 971 PNG_EMPTY); 972 # endif 973 #endif 974 975 /* Reset the CRC variable */ 976 PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY); 977 978 /* Write the "data" buffer to whatever output you are using */ 979 PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr, 980 png_const_bytep data, png_size_t length),PNG_EMPTY); 981 982 /* Read and check the PNG file signature */ 983 PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr, 984 png_inforp info_ptr),PNG_EMPTY); 985 986 /* Read the chunk header (length + type name) */ 987 PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr), 988 PNG_EMPTY); 989 990 /* Read data from whatever input you are using into the "data" buffer */ 991 PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data, 992 png_size_t length),PNG_EMPTY); 993 994 /* Read bytes into buf, and update png_ptr->crc */ 995 PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf, 996 png_uint_32 length),PNG_EMPTY); 997 998 /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */ 999 PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr, 1000 png_uint_32 skip),PNG_EMPTY); 1001 1002 /* Read the CRC from the file and compare it to the libpng calculated CRC */ 1003 PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY); 1004 1005 /* Calculate the CRC over a section of data. Note that we are only 1006 * passing a maximum of 64K on systems that have this as a memory limit, 1007 * since this is the maximum buffer size we can specify. 1008 */ 1009 PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr, 1010 png_const_bytep ptr, png_size_t length),PNG_EMPTY); 1011 1012 #ifdef PNG_WRITE_FLUSH_SUPPORTED 1013 PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY); 1014 #endif 1015 1016 /* Write various chunks */ 1017 1018 /* Write the IHDR chunk, and update the png_struct with the necessary 1019 * information. 1020 */ 1021 PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr, 1022 png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, 1023 int compression_method, int filter_method, int interlace_method),PNG_EMPTY); 1024 1025 PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr, 1026 png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY); 1027 1028 PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr, 1029 png_const_bytep row_data, png_alloc_size_t row_data_length, int flush), 1030 PNG_EMPTY); 1031 1032 PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY); 1033 1034 #ifdef PNG_WRITE_gAMA_SUPPORTED 1035 PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr, 1036 png_fixed_point file_gamma),PNG_EMPTY); 1037 #endif 1038 1039 #ifdef PNG_WRITE_sBIT_SUPPORTED 1040 PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr, 1041 png_const_color_8p sbit, int color_type),PNG_EMPTY); 1042 #endif 1043 1044 #ifdef PNG_WRITE_cHRM_SUPPORTED 1045 PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr, 1046 const png_xy *xy), PNG_EMPTY); 1047 /* The xy value must have been previously validated */ 1048 #endif 1049 1050 #ifdef PNG_WRITE_sRGB_SUPPORTED 1051 PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr, 1052 int intent),PNG_EMPTY); 1053 #endif 1054 1055 #ifdef PNG_WRITE_iCCP_SUPPORTED 1056 PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr, 1057 png_const_charp name, png_const_bytep profile), PNG_EMPTY); 1058 /* The profile must have been previously validated for correctness, the 1059 * length comes from the first four bytes. Only the base, deflate, 1060 * compression is supported. 1061 */ 1062 #endif 1063 1064 #ifdef PNG_WRITE_sPLT_SUPPORTED 1065 PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr, 1066 png_const_sPLT_tp palette),PNG_EMPTY); 1067 #endif 1068 1069 #ifdef PNG_WRITE_tRNS_SUPPORTED 1070 PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr, 1071 png_const_bytep trans, png_const_color_16p values, int number, 1072 int color_type),PNG_EMPTY); 1073 #endif 1074 1075 #ifdef PNG_WRITE_bKGD_SUPPORTED 1076 PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr, 1077 png_const_color_16p values, int color_type),PNG_EMPTY); 1078 #endif 1079 1080 #ifdef PNG_WRITE_hIST_SUPPORTED 1081 PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr, 1082 png_const_uint_16p hist, int num_hist),PNG_EMPTY); 1083 #endif 1084 1085 /* Chunks that have keywords */ 1086 #ifdef PNG_WRITE_tEXt_SUPPORTED 1087 PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr, 1088 png_const_charp key, png_const_charp text, png_size_t text_len),PNG_EMPTY); 1089 #endif 1090 1091 #ifdef PNG_WRITE_zTXt_SUPPORTED 1092 PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp 1093 key, png_const_charp text, png_size_t text_len, int compression),PNG_EMPTY); 1094 #endif 1095 1096 #ifdef PNG_WRITE_iTXt_SUPPORTED 1097 PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr, 1098 int compression, png_const_charp key, png_const_charp lang, 1099 png_const_charp lang_key, png_const_charp text),PNG_EMPTY); 1100 #endif 1101 1102 #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */ 1103 PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr, 1104 png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY); 1105 #endif 1106 1107 #ifdef PNG_WRITE_oFFs_SUPPORTED 1108 PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr, 1109 png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY); 1110 #endif 1111 1112 #ifdef PNG_WRITE_pCAL_SUPPORTED 1113 PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr, 1114 png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams, 1115 png_const_charp units, png_charpp params),PNG_EMPTY); 1116 #endif 1117 1118 #ifdef PNG_WRITE_pHYs_SUPPORTED 1119 PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr, 1120 png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit, 1121 int unit_type),PNG_EMPTY); 1122 #endif 1123 1124 #ifdef PNG_WRITE_tIME_SUPPORTED 1125 PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr, 1126 png_const_timep mod_time),PNG_EMPTY); 1127 #endif 1128 1129 #ifdef PNG_WRITE_sCAL_SUPPORTED 1130 PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr, 1131 int unit, png_const_charp width, png_const_charp height),PNG_EMPTY); 1132 #endif 1133 1134 /* Called when finished processing a row of data */ 1135 PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr), 1136 PNG_EMPTY); 1137 1138 /* Internal use only. Called before first row of data */ 1139 PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr), 1140 PNG_EMPTY); 1141 1142 /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an 1143 * array of png_ptr->width pixels. If the image is not interlaced or this 1144 * is the final pass this just does a memcpy, otherwise the "display" flag 1145 * is used to determine whether to copy pixels that are not in the current pass. 1146 * 1147 * Because 'png_do_read_interlace' (below) replicates pixels this allows this 1148 * function to achieve the documented 'blocky' appearance during interlaced read 1149 * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row' 1150 * are not changed if they are not in the current pass, when display is 0. 1151 * 1152 * 'display' must be 0 or 1, otherwise the memcpy will be done regardless. 1153 * 1154 * The API always reads from the png_struct row buffer and always assumes that 1155 * it is full width (png_do_read_interlace has already been called.) 1156 * 1157 * This function is only ever used to write to row buffers provided by the 1158 * caller of the relevant libpng API and the row must have already been 1159 * transformed by the read transformations. 1160 * 1161 * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed 1162 * bitmasks for use within the code, otherwise runtime generated masks are used. 1163 * The default is compile time masks. 1164 */ 1165 #ifndef PNG_USE_COMPILE_TIME_MASKS 1166 # define PNG_USE_COMPILE_TIME_MASKS 1 1167 #endif 1168 PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr, 1169 png_bytep row, int display),PNG_EMPTY); 1170 1171 #ifdef PNG_READ_INTERLACING_SUPPORTED 1172 /* Expand an interlaced row: the 'row_info' describes the pass data that has 1173 * been read in and must correspond to the pixels in 'row', the pixels are 1174 * expanded (moved apart) in 'row' to match the final layout, when doing this 1175 * the pixels are *replicated* to the intervening space. This is essential for 1176 * the correct operation of png_combine_row, above. 1177 */ 1178 PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info, 1179 png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY); 1180 #endif 1181 1182 /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */ 1183 1184 #ifdef PNG_WRITE_INTERLACING_SUPPORTED 1185 /* Grab pixels out of a row for an interlaced pass */ 1186 PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info, 1187 png_bytep row, int pass),PNG_EMPTY); 1188 #endif 1189 1190 /* Unfilter a row: check the filter value before calling this, there is no point 1191 * calling it for PNG_FILTER_VALUE_NONE. 1192 */ 1193 PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop 1194 row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY); 1195 1196 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info, 1197 png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1198 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop 1199 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1200 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop 1201 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1202 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop 1203 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1204 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop 1205 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1206 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop 1207 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1208 PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop 1209 row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); 1210 1211 /* Choose the best filter to use and filter the row data */ 1212 PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr, 1213 png_row_infop row_info),PNG_EMPTY); 1214 1215 #ifdef PNG_SEQUENTIAL_READ_SUPPORTED 1216 PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr, 1217 png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY); 1218 /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer 1219 * is NULL the function checks, instead, for the end of the stream. In this 1220 * case a benign error will be issued if the stream end is not found or if 1221 * extra data has to be consumed. 1222 */ 1223 PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr), 1224 PNG_EMPTY); 1225 /* This cleans up when the IDAT LZ stream does not end when the last image 1226 * byte is read; there is still some pending input. 1227 */ 1228 1229 PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr), 1230 PNG_EMPTY); 1231 /* Finish a row while reading, dealing with interlacing passes, etc. */ 1232 #endif /* PNG_SEQUENTIAL_READ_SUPPORTED */ 1233 1234 /* Initialize the row buffers, etc. */ 1235 PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY); 1236 1237 #ifdef PNG_READ_TRANSFORMS_SUPPORTED 1238 /* Optional call to update the users info structure */ 1239 PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr, 1240 png_inforp info_ptr),PNG_EMPTY); 1241 #endif 1242 1243 /* Shared transform functions, defined in pngtran.c */ 1244 #if defined(PNG_WRITE_FILLER_SUPPORTED) || \ 1245 defined(PNG_READ_STRIP_ALPHA_SUPPORTED) 1246 PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info, 1247 png_bytep row, int at_start),PNG_EMPTY); 1248 #endif 1249 1250 #ifdef PNG_16BIT_SUPPORTED 1251 #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) 1252 PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info, 1253 png_bytep row),PNG_EMPTY); 1254 #endif 1255 #endif 1256 1257 #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ 1258 defined(PNG_WRITE_PACKSWAP_SUPPORTED) 1259 PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info, 1260 png_bytep row),PNG_EMPTY); 1261 #endif 1262 1263 #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) 1264 PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info, 1265 png_bytep row),PNG_EMPTY); 1266 #endif 1267 1268 #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) 1269 PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info, 1270 png_bytep row),PNG_EMPTY); 1271 #endif 1272 1273 /* The following decodes the appropriate chunks, and does error correction, 1274 * then calls the appropriate callback for the chunk if it is valid. 1275 */ 1276 1277 /* Decode the IHDR chunk */ 1278 PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr, 1279 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1280 PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr, 1281 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1282 PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr, 1283 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1284 1285 #ifdef PNG_READ_bKGD_SUPPORTED 1286 PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr, 1287 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1288 #endif 1289 1290 #ifdef PNG_READ_cHRM_SUPPORTED 1291 PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr, 1292 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1293 #endif 1294 1295 #ifdef PNG_READ_gAMA_SUPPORTED 1296 PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr, 1297 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1298 #endif 1299 1300 #ifdef PNG_READ_hIST_SUPPORTED 1301 PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr, 1302 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1303 #endif 1304 1305 #ifdef PNG_READ_iCCP_SUPPORTED 1306 PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr, 1307 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1308 #endif /* PNG_READ_iCCP_SUPPORTED */ 1309 1310 #ifdef PNG_READ_iTXt_SUPPORTED 1311 PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr, 1312 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1313 #endif 1314 1315 #ifdef PNG_READ_oFFs_SUPPORTED 1316 PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr, 1317 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1318 #endif 1319 1320 #ifdef PNG_READ_pCAL_SUPPORTED 1321 PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr, 1322 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1323 #endif 1324 1325 #ifdef PNG_READ_pHYs_SUPPORTED 1326 PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr, 1327 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1328 #endif 1329 1330 #ifdef PNG_READ_sBIT_SUPPORTED 1331 PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr, 1332 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1333 #endif 1334 1335 #ifdef PNG_READ_sCAL_SUPPORTED 1336 PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr, 1337 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1338 #endif 1339 1340 #ifdef PNG_READ_sPLT_SUPPORTED 1341 PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr, 1342 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1343 #endif /* PNG_READ_sPLT_SUPPORTED */ 1344 1345 #ifdef PNG_READ_sRGB_SUPPORTED 1346 PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr, 1347 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1348 #endif 1349 1350 #ifdef PNG_READ_tEXt_SUPPORTED 1351 PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr, 1352 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1353 #endif 1354 1355 #ifdef PNG_READ_tIME_SUPPORTED 1356 PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr, 1357 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1358 #endif 1359 1360 #ifdef PNG_READ_tRNS_SUPPORTED 1361 PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr, 1362 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1363 #endif 1364 1365 #ifdef PNG_READ_zTXt_SUPPORTED 1366 PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr, 1367 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1368 #endif 1369 1370 PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr, 1371 png_uint_32 chunk_name),PNG_EMPTY); 1372 1373 PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr, 1374 png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY); 1375 /* This is the function that gets called for unknown chunks. The 'keep' 1376 * argument is either non-zero for a known chunk that has been set to be 1377 * handled as unknown or zero for an unknown chunk. By default the function 1378 * just skips the chunk or errors out if it is critical. 1379 */ 1380 1381 #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\ 1382 defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED) 1383 PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling, 1384 (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY); 1385 /* Exactly as the API png_handle_as_unknown() except that the argument is a 1386 * 32-bit chunk name, not a string. 1387 */ 1388 #endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */ 1389 1390 /* Handle the transformations for reading and writing */ 1391 #ifdef PNG_READ_TRANSFORMS_SUPPORTED 1392 PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr, 1393 png_row_infop row_info),PNG_EMPTY); 1394 #endif 1395 #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED 1396 PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr, 1397 png_row_infop row_info),PNG_EMPTY); 1398 #endif 1399 1400 #ifdef PNG_READ_TRANSFORMS_SUPPORTED 1401 PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr), 1402 PNG_EMPTY); 1403 #endif 1404 1405 #ifdef PNG_PROGRESSIVE_READ_SUPPORTED 1406 PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr, 1407 png_inforp info_ptr),PNG_EMPTY); 1408 PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr, 1409 png_inforp info_ptr),PNG_EMPTY); 1410 PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY); 1411 PNG_INTERNAL_FUNCTION(void,png_push_crc_skip,(png_structrp png_ptr, 1412 png_uint_32 length),PNG_EMPTY); 1413 PNG_INTERNAL_FUNCTION(void,png_push_crc_finish,(png_structrp png_ptr), 1414 PNG_EMPTY); 1415 PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr), 1416 PNG_EMPTY); 1417 PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr, 1418 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY); 1419 PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY); 1420 PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr, 1421 png_bytep buffer, png_size_t buffer_length),PNG_EMPTY); 1422 PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr), 1423 PNG_EMPTY); 1424 PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr, 1425 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1426 PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr, 1427 png_inforp info_ptr),PNG_EMPTY); 1428 PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr, 1429 png_inforp info_ptr),PNG_EMPTY); 1430 PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr, 1431 png_bytep row),PNG_EMPTY); 1432 PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr, 1433 png_inforp info_ptr),PNG_EMPTY); 1434 PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr, 1435 png_inforp info_ptr),PNG_EMPTY); 1436 PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr), 1437 PNG_EMPTY); 1438 # ifdef PNG_READ_tEXt_SUPPORTED 1439 PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr, 1440 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1441 PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr, 1442 png_inforp info_ptr),PNG_EMPTY); 1443 # endif 1444 # ifdef PNG_READ_zTXt_SUPPORTED 1445 PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr, 1446 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1447 PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr, 1448 png_inforp info_ptr),PNG_EMPTY); 1449 # endif 1450 # ifdef PNG_READ_iTXt_SUPPORTED 1451 PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr, 1452 png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); 1453 PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr, 1454 png_inforp info_ptr),PNG_EMPTY); 1455 # endif 1456 1457 #endif /* PNG_PROGRESSIVE_READ_SUPPORTED */ 1458 1459 /* Added at libpng version 1.6.0 */ 1460 #ifdef PNG_GAMMA_SUPPORTED 1461 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr, 1462 png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY); 1463 /* Set the colorspace gamma with a value provided by the application or by 1464 * the gAMA chunk on read. The value will override anything set by an ICC 1465 * profile. 1466 */ 1467 1468 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr, 1469 png_inforp info_ptr), PNG_EMPTY); 1470 /* Synchronize the info 'valid' flags with the colorspace */ 1471 1472 PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr, 1473 png_inforp info_ptr), PNG_EMPTY); 1474 /* Copy the png_struct colorspace to the info_struct and call the above to 1475 * synchronize the flags. Checks for NULL info_ptr and does nothing. 1476 */ 1477 #endif 1478 1479 /* Added at libpng version 1.4.0 */ 1480 #ifdef PNG_COLORSPACE_SUPPORTED 1481 /* These internal functions are for maintaining the colorspace structure within 1482 * a png_info or png_struct (or, indeed, both). 1483 */ 1484 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities, 1485 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy, 1486 int preferred), PNG_EMPTY); 1487 1488 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints, 1489 (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ, 1490 int preferred), PNG_EMPTY); 1491 1492 #ifdef PNG_sRGB_SUPPORTED 1493 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr, 1494 png_colorspacerp colorspace, int intent), PNG_EMPTY); 1495 /* This does set the colorspace gAMA and cHRM values too, but doesn't set the 1496 * flags to write them, if it returns false there was a problem and an error 1497 * message has already been output (but the colorspace may still need to be 1498 * synced to record the invalid flag). 1499 */ 1500 #endif /* sRGB */ 1501 1502 #ifdef PNG_iCCP_SUPPORTED 1503 PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr, 1504 png_colorspacerp colorspace, png_const_charp name, 1505 png_uint_32 profile_length, png_const_bytep profile, int color_type), 1506 PNG_EMPTY); 1507 /* The 'name' is used for information only */ 1508 1509 /* Routines for checking parts of an ICC profile. */ 1510 PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr, 1511 png_colorspacerp colorspace, png_const_charp name, 1512 png_uint_32 profile_length), PNG_EMPTY); 1513 PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr, 1514 png_colorspacerp colorspace, png_const_charp name, 1515 png_uint_32 profile_length, 1516 png_const_bytep profile /* first 132 bytes only */, int color_type), 1517 PNG_EMPTY); 1518 PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr, 1519 png_colorspacerp colorspace, png_const_charp name, 1520 png_uint_32 profile_length, 1521 png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY); 1522 #ifdef PNG_sRGB_SUPPORTED 1523 PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,( 1524 png_const_structrp png_ptr, png_colorspacerp colorspace, 1525 png_const_bytep profile, uLong adler), PNG_EMPTY); 1526 /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may 1527 * be zero to indicate that it is not available. It is used, if provided, 1528 * as a fast check on the profile when checking to see if it is sRGB. 1529 */ 1530 #endif 1531 #endif /* iCCP */ 1532 1533 #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED 1534 PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients, 1535 (png_structrp png_ptr), PNG_EMPTY); 1536 /* Set the rgb_to_gray coefficients from the colorspace Y values */ 1537 #endif /* READ_RGB_TO_GRAY */ 1538 #endif /* COLORSPACE */ 1539 1540 /* Added at libpng version 1.4.0 */ 1541 PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr, 1542 png_uint_32 width, png_uint_32 height, int bit_depth, 1543 int color_type, int interlace_type, int compression_type, 1544 int filter_type),PNG_EMPTY); 1545 1546 /* Added at libpng version 1.5.10 */ 1547 #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \ 1548 defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED) 1549 PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes, 1550 (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY); 1551 #endif 1552 1553 #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED) 1554 PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr, 1555 png_const_charp name),PNG_NORETURN); 1556 #endif 1557 1558 /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite 1559 * the end. Always leaves the buffer nul terminated. Never errors out (and 1560 * there is no error code.) 1561 */ 1562 PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize, 1563 size_t pos, png_const_charp string),PNG_EMPTY); 1564 1565 /* Various internal functions to handle formatted warning messages, currently 1566 * only implemented for warnings. 1567 */ 1568 #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED) 1569 /* Utility to dump an unsigned value into a buffer, given a start pointer and 1570 * and end pointer (which should point just *beyond* the end of the buffer!) 1571 * Returns the pointer to the start of the formatted string. This utility only 1572 * does unsigned values. 1573 */ 1574 PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start, 1575 png_charp end, int format, png_alloc_size_t number),PNG_EMPTY); 1576 1577 /* Convenience macro that takes an array: */ 1578 #define PNG_FORMAT_NUMBER(buffer,format,number) \ 1579 png_format_number(buffer, buffer + (sizeof buffer), format, number) 1580 1581 /* Suggested size for a number buffer (enough for 64 bits and a sign!) */ 1582 #define PNG_NUMBER_BUFFER_SIZE 24 1583 1584 /* These are the integer formats currently supported, the name is formed from 1585 * the standard printf(3) format string. 1586 */ 1587 #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */ 1588 #define PNG_NUMBER_FORMAT_02u 2 1589 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */ 1590 #define PNG_NUMBER_FORMAT_02d 2 1591 #define PNG_NUMBER_FORMAT_x 3 1592 #define PNG_NUMBER_FORMAT_02x 4 1593 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */ 1594 #endif 1595 1596 #ifdef PNG_WARNINGS_SUPPORTED 1597 /* New defines and members adding in libpng-1.5.4 */ 1598 # define PNG_WARNING_PARAMETER_SIZE 32 1599 # define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */ 1600 1601 /* An l-value of this type has to be passed to the APIs below to cache the 1602 * values of the parameters to a formatted warning message. 1603 */ 1604 typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][ 1605 PNG_WARNING_PARAMETER_SIZE]; 1606 1607 PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p, 1608 int number, png_const_charp string),PNG_EMPTY); 1609 /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters, 1610 * including the trailing '\0'. 1611 */ 1612 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned, 1613 (png_warning_parameters p, int number, int format, png_alloc_size_t value), 1614 PNG_EMPTY); 1615 /* Use png_alloc_size_t because it is an unsigned type as big as any we 1616 * need to output. Use the following for a signed value. 1617 */ 1618 PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed, 1619 (png_warning_parameters p, int number, int format, png_int_32 value), 1620 PNG_EMPTY); 1621 1622 PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr, 1623 png_warning_parameters p, png_const_charp message),PNG_EMPTY); 1624 /* 'message' follows the X/Open approach of using @1, @2 to insert 1625 * parameters previously supplied using the above functions. Errors in 1626 * specifying the parameters will simply result in garbage substitutions. 1627 */ 1628 #endif 1629 1630 #ifdef PNG_BENIGN_ERRORS_SUPPORTED 1631 /* Application errors (new in 1.6); use these functions (declared below) for 1632 * errors in the parameters or order of API function calls on read. The 1633 * 'warning' should be used for an error that can be handled completely; the 1634 * 'error' for one which can be handled safely but which may lose application 1635 * information or settings. 1636 * 1637 * By default these both result in a png_error call prior to release, while in a 1638 * released version the 'warning' is just a warning. However if the application 1639 * explicitly disables benign errors (explicitly permitting the code to lose 1640 * information) they both turn into warnings. 1641 * 1642 * If benign errors aren't supported they end up as the corresponding base call 1643 * (png_warning or png_error.) 1644 */ 1645 PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr, 1646 png_const_charp message),PNG_EMPTY); 1647 /* The application provided invalid parameters to an API function or called 1648 * an API function at the wrong time, libpng can completely recover. 1649 */ 1650 1651 PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr, 1652 png_const_charp message),PNG_EMPTY); 1653 /* As above but libpng will ignore the call, or attempt some other partial 1654 * recovery from the error. 1655 */ 1656 #else 1657 # define png_app_warning(pp,s) png_warning(pp,s) 1658 # define png_app_error(pp,s) png_error(pp,s) 1659 #endif 1660 1661 PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr, 1662 png_const_charp message, int error),PNG_EMPTY); 1663 /* Report a recoverable issue in chunk data. On read this is used to report 1664 * a problem found while reading a particular chunk and the 1665 * png_chunk_benign_error or png_chunk_warning function is used as 1666 * appropriate. On write this is used to report an error that comes from 1667 * data set via an application call to a png_set_ API and png_app_error or 1668 * png_app_warning is used as appropriate. 1669 * 1670 * The 'error' parameter must have one of the following values: 1671 */ 1672 #define PNG_CHUNK_WARNING 0 /* never an error */ 1673 #define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */ 1674 #define PNG_CHUNK_ERROR 2 /* always an error */ 1675 1676 /* ASCII to FP interfaces, currently only implemented if sCAL 1677 * support is required. 1678 */ 1679 #if defined(PNG_sCAL_SUPPORTED) 1680 /* MAX_DIGITS is actually the maximum number of characters in an sCAL 1681 * width or height, derived from the precision (number of significant 1682 * digits - a build time settable option) and assumptions about the 1683 * maximum ridiculous exponent. 1684 */ 1685 #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/) 1686 1687 #ifdef PNG_FLOATING_POINT_SUPPORTED 1688 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr, 1689 png_charp ascii, png_size_t size, double fp, unsigned int precision), 1690 PNG_EMPTY); 1691 #endif /* FLOATING_POINT */ 1692 1693 #ifdef PNG_FIXED_POINT_SUPPORTED 1694 PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr, 1695 png_charp ascii, png_size_t size, png_fixed_point fp),PNG_EMPTY); 1696 #endif /* FIXED_POINT */ 1697 #endif /* sCAL */ 1698 1699 #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED) 1700 /* An internal API to validate the format of a floating point number. 1701 * The result is the index of the next character. If the number is 1702 * not valid it will be the index of a character in the supposed number. 1703 * 1704 * The format of a number is defined in the PNG extensions specification 1705 * and this API is strictly conformant to that spec, not anyone elses! 1706 * 1707 * The format as a regular expression is: 1708 * 1709 * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)? 1710 * 1711 * or: 1712 * 1713 * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)? 1714 * 1715 * The complexity is that either integer or fraction must be present and the 1716 * fraction is permitted to have no digits only if the integer is present. 1717 * 1718 * NOTE: The dangling E problem. 1719 * There is a PNG valid floating point number in the following: 1720 * 1721 * PNG floating point numbers are not greedy. 1722 * 1723 * Working this out requires *TWO* character lookahead (because of the 1724 * sign), the parser does not do this - it will fail at the 'r' - this 1725 * doesn't matter for PNG sCAL chunk values, but it requires more care 1726 * if the value were ever to be embedded in something more complex. Use 1727 * ANSI-C strtod if you need the lookahead. 1728 */ 1729 /* State table for the parser. */ 1730 #define PNG_FP_INTEGER 0 /* before or in integer */ 1731 #define PNG_FP_FRACTION 1 /* before or in fraction */ 1732 #define PNG_FP_EXPONENT 2 /* before or in exponent */ 1733 #define PNG_FP_STATE 3 /* mask for the above */ 1734 #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */ 1735 #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */ 1736 #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */ 1737 #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */ 1738 #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */ 1739 1740 /* These three values don't affect the parser. They are set but not used. 1741 */ 1742 #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */ 1743 #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */ 1744 #define PNG_FP_NONZERO 256 /* A non-zero value */ 1745 #define PNG_FP_STICKY 448 /* The above three flags */ 1746 1747 /* This is available for the caller to store in 'state' if required. Do not 1748 * call the parser after setting it (the parser sometimes clears it.) 1749 */ 1750 #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */ 1751 1752 /* Result codes for the parser (boolean - true meants ok, false means 1753 * not ok yet.) 1754 */ 1755 #define PNG_FP_MAYBE 0 /* The number may be valid in the future */ 1756 #define PNG_FP_OK 1 /* The number is valid */ 1757 1758 /* Tests on the sticky non-zero and negative flags. To pass these checks 1759 * the state must also indicate that the whole number is valid - this is 1760 * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this 1761 * is equivalent to PNG_FP_OK above.) 1762 */ 1763 #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO) 1764 /* NZ_MASK: the string is valid and a non-zero negative value */ 1765 #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO) 1766 /* Z MASK: the string is valid and a non-zero value. */ 1767 /* PNG_FP_SAW_DIGIT: the string is valid. */ 1768 #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT) 1769 #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK) 1770 #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK) 1771 1772 /* The actual parser. This can be called repeatedly. It updates 1773 * the index into the string and the state variable (which must 1774 * be initialized to 0). It returns a result code, as above. There 1775 * is no point calling the parser any more if it fails to advance to 1776 * the end of the string - it is stuck on an invalid character (or 1777 * terminated by '\0'). 1778 * 1779 * Note that the pointer will consume an E or even an E+ and then leave 1780 * a 'maybe' state even though a preceding integer.fraction is valid. 1781 * The PNG_FP_WAS_VALID flag indicates that a preceding substring was 1782 * a valid number. It's possible to recover from this by calling 1783 * the parser again (from the start, with state 0) but with a string 1784 * that omits the last character (i.e. set the size to the index of 1785 * the problem character.) This has not been tested within libpng. 1786 */ 1787 PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string, 1788 png_size_t size, int *statep, png_size_tp whereami),PNG_EMPTY); 1789 1790 /* This is the same but it checks a complete string and returns true 1791 * only if it just contains a floating point number. As of 1.5.4 this 1792 * function also returns the state at the end of parsing the number if 1793 * it was valid (otherwise it returns 0.) This can be used for testing 1794 * for negative or zero values using the sticky flag. 1795 */ 1796 PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string, 1797 png_size_t size),PNG_EMPTY); 1798 #endif /* pCAL || sCAL */ 1799 1800 #if defined(PNG_GAMMA_SUPPORTED) ||\ 1801 defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED) 1802 /* Added at libpng version 1.5.0 */ 1803 /* This is a utility to provide a*times/div (rounded) and indicate 1804 * if there is an overflow. The result is a boolean - false (0) 1805 * for overflow, true (1) if no overflow, in which case *res 1806 * holds the result. 1807 */ 1808 PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a, 1809 png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY); 1810 #endif 1811 1812 #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED) 1813 /* Same deal, but issue a warning on overflow and return 0. */ 1814 PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn, 1815 (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by, 1816 png_int_32 divided_by),PNG_EMPTY); 1817 #endif 1818 1819 #ifdef PNG_GAMMA_SUPPORTED 1820 /* Calculate a reciprocal - used for gamma values. This returns 1821 * 0 if the argument is 0 in order to maintain an undefined value; 1822 * there are no warnings. 1823 */ 1824 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a), 1825 PNG_EMPTY); 1826 1827 #ifdef PNG_READ_GAMMA_SUPPORTED 1828 /* The same but gives a reciprocal of the product of two fixed point 1829 * values. Accuracy is suitable for gamma calculations but this is 1830 * not exact - use png_muldiv for that. Only required at present on read. 1831 */ 1832 PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a, 1833 png_fixed_point b),PNG_EMPTY); 1834 #endif 1835 1836 /* Return true if the gamma value is significantly different from 1.0 */ 1837 PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value), 1838 PNG_EMPTY); 1839 #endif 1840 1841 #ifdef PNG_READ_GAMMA_SUPPORTED 1842 /* Internal fixed point gamma correction. These APIs are called as 1843 * required to convert single values - they don't need to be fast, 1844 * they are not used when processing image pixel values. 1845 * 1846 * While the input is an 'unsigned' value it must actually be the 1847 * correct bit value - 0..255 or 0..65535 as required. 1848 */ 1849 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr, 1850 unsigned int value, png_fixed_point gamma_value),PNG_EMPTY); 1851 PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value, 1852 png_fixed_point gamma_value),PNG_EMPTY); 1853 PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value, 1854 png_fixed_point gamma_value),PNG_EMPTY); 1855 PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr), 1856 PNG_EMPTY); 1857 PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr, 1858 int bit_depth),PNG_EMPTY); 1859 #endif 1860 1861 /* SIMPLIFIED READ/WRITE SUPPORT */ 1862 #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\ 1863 defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) 1864 /* The internal structure that png_image::opaque points to. */ 1865 typedef struct png_control 1866 { 1867 png_structp png_ptr; 1868 png_infop info_ptr; 1869 png_voidp error_buf; /* Always a jmp_buf at present. */ 1870 1871 png_const_bytep memory; /* Memory buffer. */ 1872 png_size_t size; /* Size of the memory buffer. */ 1873 1874 unsigned int for_write :1; /* Otherwise it is a read structure */ 1875 unsigned int owned_file :1; /* We own the file in io_ptr */ 1876 } png_control; 1877 1878 /* Return the pointer to the jmp_buf from a png_control: necessary because C 1879 * does not reveal the type of the elements of jmp_buf. 1880 */ 1881 #ifdef __cplusplus 1882 # define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0]) 1883 #else 1884 # define png_control_jmp_buf(pc) ((pc)->error_buf) 1885 #endif 1886 1887 /* Utility to safely execute a piece of libpng code catching and logging any 1888 * errors that might occur. Returns true on success, false on failure (either 1889 * of the function or as a result of a png_error.) 1890 */ 1891 PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr, 1892 png_const_charp error_message),PNG_NORETURN); 1893 1894 #ifdef PNG_WARNINGS_SUPPORTED 1895 PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr, 1896 png_const_charp warning_message),PNG_EMPTY); 1897 #else 1898 # define png_safe_warning 0/*dummy argument*/ 1899 #endif 1900 1901 PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image, 1902 int (*function)(png_voidp), png_voidp arg),PNG_EMPTY); 1903 1904 /* Utility to log an error; this also cleans up the png_image; the function 1905 * always returns 0 (false). 1906 */ 1907 PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image, 1908 png_const_charp error_message),PNG_EMPTY); 1909 1910 #ifndef PNG_SIMPLIFIED_READ_SUPPORTED 1911 /* png_image_free is used by the write code but not exported */ 1912 PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY); 1913 #endif /* !SIMPLIFIED_READ */ 1914 1915 #endif /* SIMPLIFIED READ/WRITE */ 1916 1917 /* These are initialization functions for hardware specific PNG filter 1918 * optimizations; list these here then select the appropriate one at compile 1919 * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined 1920 * the generic code is used. 1921 */ 1922 #ifdef PNG_FILTER_OPTIMIZATIONS 1923 PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr, 1924 unsigned int bpp), PNG_EMPTY); 1925 /* Just declare the optimization that will be used */ 1926 #else 1927 /* List *all* the possible optimizations here - this branch is required if 1928 * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in 1929 * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing. 1930 */ 1931 PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon, 1932 (png_structp png_ptr, unsigned int bpp), PNG_EMPTY); 1933 #endif 1934 1935 #ifdef PNG_INDEX_SUPPORTED 1936 PNG_INTERNAL_FUNCTION(void, png_seek_data, (png_structp png_ptr, 1937 png_uint_32 length), PNG_EMPTY); 1938 PNG_INTERNAL_FUNCTION(int, png_opt_crc_finish,(png_structrp png_ptr, 1939 png_uint_32 skip), PNG_EMPTY); 1940 PNG_INTERNAL_FUNCTION(void, png_set_interlaced_pass,(png_structrp png_ptr, 1941 int pass), PNG_EMPTY); 1942 #endif 1943 1944 /* Maintainer: Put new private prototypes here ^ */ 1945 1946 #include "pngdebug.h" 1947 1948 #ifdef __cplusplus 1949 } 1950 #endif 1951 1952 #endif /* PNG_VERSION_INFO_ONLY */ 1953 #endif /* PNGPRIV_H */ 1954