/* pngpriv.h - private declarations for use inside libpng * * Last changed in libpng 1.6.18 [(PENDING RELEASE)] * Copyright (c) 1998-2015 Glenn Randers-Pehrson * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) * * This code is released under the libpng license. * For conditions of distribution and use, see the disclaimer * and license in png.h */ /* The symbols declared in this file (including the functions declared * as extern) are PRIVATE. They are not part of the libpng public * interface, and are not recommended for use by regular applications. * Some of them may become public in the future; others may stay private, * change in an incompatible way, or even disappear. * Although the libpng users are not forbidden to include this header, * they should be well aware of the issues that may arise from doing so. */ #ifndef PNGPRIV_H #define PNGPRIV_H /* Feature Test Macros. The following are defined here to ensure that correctly * implemented libraries reveal the APIs libpng needs to build and hide those * that are not needed and potentially damaging to the compilation. * * Feature Test Macros must be defined before any system header is included (see * POSIX 1003.1 2.8.2 "POSIX Symbols." * * These macros only have an effect if the operating system supports either * POSIX 1003.1 or C99, or both. On other operating systems (particularly * Windows/Visual Studio) there is no effect; the OS specific tests below are * still required (as of 2011-05-02.) */ #define _POSIX_SOURCE 1 /* Just the POSIX 1003.1 and C89 APIs */ #ifndef PNG_VERSION_INFO_ONLY /* Standard library headers not required by png.h: */ # include # include #endif #define PNGLIB_BUILD /*libpng is being built, not used*/ /* If HAVE_CONFIG_H is defined during the build then the build system must * provide an appropriate "config.h" file on the include path. The header file * must provide definitions as required below (search for "HAVE_CONFIG_H"); * see configure.ac for more details of the requirements. The macro * "PNG_NO_CONFIG_H" is provided for maintainers to test for dependencies on * 'configure'; define this macro to prevent the configure build including the * configure generated config.h. Libpng is expected to compile without *any* * special build system support on a reasonably ANSI-C compliant system. */ #if defined(HAVE_CONFIG_H) && !defined(PNG_NO_CONFIG_H) # include /* Pick up the definition of 'restrict' from config.h if it was read: */ # define PNG_RESTRICT restrict #endif /* To support symbol prefixing it is necessary to know *before* including png.h * whether the fixed point (and maybe other) APIs are exported, because if they * are not internal definitions may be required. This is handled below just * before png.h is included, but load the configuration now if it is available. */ #ifndef PNGLCONF_H # include "pnglibconf.h" #endif /* Local renames may change non-exported API functions from png.h */ #if defined(PNG_PREFIX) && !defined(PNGPREFIX_H) # include "pngprefix.h" #endif #ifdef PNG_USER_CONFIG # include "pngusr.h" /* These should have been defined in pngusr.h */ # ifndef PNG_USER_PRIVATEBUILD # define PNG_USER_PRIVATEBUILD "Custom libpng build" # endif # ifndef PNG_USER_DLLFNAME_POSTFIX # define PNG_USER_DLLFNAME_POSTFIX "Cb" # endif #endif /* Compile time options. * ===================== * In a multi-arch build the compiler may compile the code several times for the * same object module, producing different binaries for different architectures. * When this happens configure-time setting of the target host options cannot be * done and this interferes with the handling of the ARM NEON optimizations, and * possibly other similar optimizations. Put additional tests here; in general * this is needed when the same option can be changed at both compile time and * run time depending on the target OS (i.e. iOS vs Android.) * * NOTE: symbol prefixing does not pass $(CFLAGS) to the preprocessor, because * this is not possible with certain compilers (Oracle SUN OS CC), as a result * it is necessary to ensure that all extern functions that *might* be used * regardless of $(CFLAGS) get declared in this file. The test on __ARM_NEON__ * below is one example of this behavior because it is controlled by the * presence or not of -mfpu=neon on the GCC command line, it is possible to do * this in $(CC), e.g. "CC=gcc -mfpu=neon", but people who build libpng rarely * do this. */ #ifndef PNG_ARM_NEON_OPT /* ARM NEON optimizations are being controlled by the compiler settings, * typically the target FPU. If the FPU has been set to NEON (-mfpu=neon * with GCC) then the compiler will define __ARM_NEON__ and we can rely * unconditionally on NEON instructions not crashing, otherwise we must * disable use of NEON instructions. * * NOTE: at present these optimizations depend on 'ALIGNED_MEMORY', so they * can only be turned on automatically if that is supported too. If * PNG_ARM_NEON_OPT is set in CPPFLAGS (to >0) then arm/arm_init.c will fail * to compile with an appropriate #error if ALIGNED_MEMORY has been turned * off. * * Note that gcc-4.9 defines __ARM_NEON instead of the deprecated * __ARM_NEON__, so we check both variants. * * To disable ARM_NEON optimizations entirely, and skip compiling the * associated assembler code, pass --enable-arm-neon=no to configure * or put -DPNG_ARM_NEON_OPT=0 in CPPFLAGS. */ # if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \ defined(PNG_ALIGNED_MEMORY_SUPPORTED) # define PNG_ARM_NEON_OPT 2 # else # define PNG_ARM_NEON_OPT 0 # endif #endif #if PNG_ARM_NEON_OPT > 0 /* NEON optimizations are to be at least considered by libpng, so enable the * callbacks to do this. */ # define PNG_FILTER_OPTIMIZATIONS png_init_filter_functions_neon /* By default the 'intrinsics' code in arm/filter_neon_intrinsics.c is used * if possible - if __ARM_NEON__ is set and the compiler version is not known * to be broken. This is controlled by PNG_ARM_NEON_IMPLEMENTATION which can * be: * * 1 The intrinsics code (the default with __ARM_NEON__) * 2 The hand coded assembler (the default without __ARM_NEON__) * * It is possible to set PNG_ARM_NEON_IMPLEMENTATION in CPPFLAGS, however * this is *NOT* supported and may cease to work even after a minor revision * to libpng. It *is* valid to do this for testing purposes, e.g. speed * testing or a new compiler, but the results should be communicated to the * libpng implementation list for incorporation in the next minor release. */ # ifndef PNG_ARM_NEON_IMPLEMENTATION # if defined(__ARM_NEON__) || defined(__ARM_NEON) # if defined(__clang__) /* At present it is unknown by the libpng developers which versions * of clang support the intrinsics, however some or perhaps all * versions do not work with the assembler so this may be * irrelevant, so just use the default (do nothing here.) */ # elif defined(__GNUC__) /* GCC 4.5.4 NEON support is known to be broken. 4.6.3 is known to * work, so if this *is* GCC, or G++, look for a version >4.5 */ # if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 6) # define PNG_ARM_NEON_IMPLEMENTATION 2 # endif /* no GNUC support */ # endif /* __GNUC__ */ # else /* !defined __ARM_NEON__ */ /* The 'intrinsics' code simply won't compile without this -mfpu=neon: */ # define PNG_ARM_NEON_IMPLEMENTATION 2 # endif /* __ARM_NEON__ */ # endif /* !PNG_ARM_NEON_IMPLEMENTATION */ # ifndef PNG_ARM_NEON_IMPLEMENTATION /* Use the intrinsics code by default. */ # define PNG_ARM_NEON_IMPLEMENTATION 1 # endif #endif /* PNG_ARM_NEON_OPT > 0 */ /* Is this a build of a DLL where compilation of the object modules requires * different preprocessor settings to those required for a simple library? If * so PNG_BUILD_DLL must be set. * * If libpng is used inside a DLL but that DLL does not export the libpng APIs * PNG_BUILD_DLL must not be set. To avoid the code below kicking in build a * static library of libpng then link the DLL against that. */ #ifndef PNG_BUILD_DLL # ifdef DLL_EXPORT /* This is set by libtool when files are compiled for a DLL; libtool * always compiles twice, even on systems where it isn't necessary. Set * PNG_BUILD_DLL in case it is necessary: */ # define PNG_BUILD_DLL # else # ifdef _WINDLL /* This is set by the Microsoft Visual Studio IDE in projects that * build a DLL. It can't easily be removed from those projects (it * isn't visible in the Visual Studio UI) so it is a fairly reliable * indication that PNG_IMPEXP needs to be set to the DLL export * attributes. */ # define PNG_BUILD_DLL # else # ifdef __DLL__ /* This is set by the Borland C system when compiling for a DLL * (as above.) */ # define PNG_BUILD_DLL # else /* Add additional compiler cases here. */ # endif # endif # endif #endif /* Setting PNG_BUILD_DLL if required */ /* See pngconf.h for more details: the builder of the library may set this on * the command line to the right thing for the specific compilation system or it * may be automagically set above (at present we know of no system where it does * need to be set on the command line.) * * PNG_IMPEXP must be set here when building the library to prevent pngconf.h * setting it to the "import" setting for a DLL build. */ #ifndef PNG_IMPEXP # ifdef PNG_BUILD_DLL # define PNG_IMPEXP PNG_DLL_EXPORT # else /* Not building a DLL, or the DLL doesn't require specific export * definitions. */ # define PNG_IMPEXP # endif #endif /* No warnings for private or deprecated functions in the build: */ #ifndef PNG_DEPRECATED # define PNG_DEPRECATED #endif #ifndef PNG_PRIVATE # define PNG_PRIVATE #endif /* Symbol preprocessing support. * * To enable listing global, but internal, symbols the following macros should * always be used to declare an extern data or function object in this file. */ #ifndef PNG_INTERNAL_DATA # define PNG_INTERNAL_DATA(type, name, array) extern type name array #endif #ifndef PNG_INTERNAL_FUNCTION # define PNG_INTERNAL_FUNCTION(type, name, args, attributes)\ extern PNG_FUNCTION(type, name, args, PNG_EMPTY attributes) #endif #ifndef PNG_INTERNAL_CALLBACK # define PNG_INTERNAL_CALLBACK(type, name, args, attributes)\ extern PNG_FUNCTION(type, (PNGCBAPI name), args, PNG_EMPTY attributes) #endif /* If floating or fixed point APIs are disabled they may still be compiled * internally. To handle this make sure they are declared as the appropriate * internal extern function (otherwise the symbol prefixing stuff won't work and * the functions will be used without definitions.) * * NOTE: although all the API functions are declared here they are not all * actually built! Because the declarations are still made it is necessary to * fake out types that they depend on. */ #ifndef PNG_FP_EXPORT # ifndef PNG_FLOATING_POINT_SUPPORTED # define PNG_FP_EXPORT(ordinal, type, name, args)\ PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY); # ifndef PNG_VERSION_INFO_ONLY typedef struct png_incomplete png_double; typedef png_double* png_doublep; typedef const png_double* png_const_doublep; typedef png_double** png_doublepp; # endif # endif #endif #ifndef PNG_FIXED_EXPORT # ifndef PNG_FIXED_POINT_SUPPORTED # define PNG_FIXED_EXPORT(ordinal, type, name, args)\ PNG_INTERNAL_FUNCTION(type, name, args, PNG_EMPTY); # endif #endif #include "png.h" /* pngconf.h does not set PNG_DLL_EXPORT unless it is required, so: */ #ifndef PNG_DLL_EXPORT # define PNG_DLL_EXPORT #endif /* SECURITY and SAFETY: * * libpng is built with support for internal limits on image dimensions and * memory usage. These are documented in scripts/pnglibconf.dfa of the * source and recorded in the machine generated header file pnglibconf.h. */ /* If you are running on a machine where you cannot allocate more * than 64K of memory at once, uncomment this. While libpng will not * normally need that much memory in a chunk (unless you load up a very * large file), zlib needs to know how big of a chunk it can use, and * libpng thus makes sure to check any memory allocation to verify it * will fit into memory. * * zlib provides 'MAXSEG_64K' which, if defined, indicates the * same limit and pngconf.h (already included) sets the limit * if certain operating systems are detected. */ #if defined(MAXSEG_64K) && !defined(PNG_MAX_MALLOC_64K) # define PNG_MAX_MALLOC_64K #endif #ifndef PNG_UNUSED /* Unused formal parameter warnings are silenced using the following macro * which is expected to have no bad effects on performance (optimizing * compilers will probably remove it entirely). Note that if you replace * it with something other than whitespace, you must include the terminating * semicolon. */ # define PNG_UNUSED(param) (void)param; #endif /* Just a little check that someone hasn't tried to define something * contradictory. */ #if (PNG_ZBUF_SIZE > 65536L) && defined(PNG_MAX_MALLOC_64K) # undef PNG_ZBUF_SIZE # define PNG_ZBUF_SIZE 65536L #endif /* If warnings or errors are turned off the code is disabled or redirected here. * From 1.5.4 functions have been added to allow very limited formatting of * error and warning messages - this code will also be disabled here. */ #ifdef PNG_WARNINGS_SUPPORTED # define PNG_WARNING_PARAMETERS(p) png_warning_parameters p; #else # define png_warning_parameter(p,number,string) ((void)0) # define png_warning_parameter_unsigned(p,number,format,value) ((void)0) # define png_warning_parameter_signed(p,number,format,value) ((void)0) # define png_formatted_warning(pp,p,message) ((void)(pp)) # define PNG_WARNING_PARAMETERS(p) #endif #ifndef PNG_ERROR_TEXT_SUPPORTED # define png_fixed_error(s1,s2) png_err(s1) #endif /* C allows up-casts from (void*) to any pointer and (const void*) to any * pointer to a const object. C++ regards this as a type error and requires an * explicit, static, cast and provides the static_cast<> rune to ensure that * const is not cast away. */ #ifdef __cplusplus # define png_voidcast(type, value) static_cast(value) # define png_constcast(type, value) const_cast(value) # define png_aligncast(type, value) \ static_cast(static_cast(value)) # define png_aligncastconst(type, value) \ static_cast(static_cast(value)) #else # define png_voidcast(type, value) (value) # define png_constcast(type, value) ((type)(value)) # define png_aligncast(type, value) ((void*)(value)) # define png_aligncastconst(type, value) ((const void*)(value)) #endif /* __cplusplus */ /* Some fixed point APIs are still required even if not exported because * they get used by the corresponding floating point APIs. This magic * deals with this: */ #ifdef PNG_FIXED_POINT_SUPPORTED # define PNGFAPI PNGAPI #else # define PNGFAPI /* PRIVATE */ #endif #ifndef PNG_VERSION_INFO_ONLY /* Other defines specific to compilers can go here. Try to keep * them inside an appropriate ifdef/endif pair for portability. */ #if defined(PNG_FLOATING_POINT_SUPPORTED) ||\ defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) /* png.c requires the following ANSI-C constants if the conversion of * floating point to ASCII is implemented therein: * * DBL_DIG Maximum number of decimal digits (can be set to any constant) * DBL_MIN Smallest normalized fp number (can be set to an arbitrary value) * DBL_MAX Maximum floating point number (can be set to an arbitrary value) */ # include # if (defined(__MWERKS__) && defined(macintosh)) || defined(applec) || \ defined(THINK_C) || defined(__SC__) || defined(TARGET_OS_MAC) /* We need to check that hasn't already been included earlier * as it seems it doesn't agree with , yet we should really use * if possible. */ # if !defined(__MATH_H__) && !defined(__MATH_H) && !defined(__cmath__) # include # endif # else # include # endif # if defined(_AMIGA) && defined(__SASC) && defined(_M68881) /* Amiga SAS/C: We must include builtin FPU functions when compiling using * MATH=68881 */ # include # endif #endif /* This provides the non-ANSI (far) memory allocation routines. */ #if defined(__TURBOC__) && defined(__MSDOS__) # include # include #endif #if defined(WIN32) || defined(_Windows) || defined(_WINDOWS) || \ defined(_WIN32) || defined(__WIN32__) # include /* defines _WINDOWS_ macro */ #endif #endif /* PNG_VERSION_INFO_ONLY */ /* Moved here around 1.5.0beta36 from pngconf.h */ /* Users may want to use these so they are not private. Any library * functions that are passed far data must be model-independent. */ /* Memory model/platform independent fns */ #ifndef PNG_ABORT # ifdef _WINDOWS_ # define PNG_ABORT() ExitProcess(0) # else # define PNG_ABORT() abort() # endif #endif /* These macros may need to be architecture dependent. */ #define PNG_ALIGN_NONE 0 /* do not use data alignment */ #define PNG_ALIGN_ALWAYS 1 /* assume unaligned accesses are OK */ #ifdef offsetof # define PNG_ALIGN_OFFSET 2 /* use offsetof to determine alignment */ #else # define PNG_ALIGN_OFFSET -1 /* prevent the use of this */ #endif #define PNG_ALIGN_SIZE 3 /* use sizeof to determine alignment */ #ifndef PNG_ALIGN_TYPE /* Default to using aligned access optimizations and requiring alignment to a * multiple of the data type size. Override in a compiler specific fashion * if necessary by inserting tests here: */ # define PNG_ALIGN_TYPE PNG_ALIGN_SIZE #endif #if PNG_ALIGN_TYPE == PNG_ALIGN_SIZE /* This is used because in some compiler implementations non-aligned * structure members are supported, so the offsetof approach below fails. * Set PNG_ALIGN_SIZE=0 for compiler combinations where unaligned access * is good for performance. Do not do this unless you have tested the result * and understand it. */ # define png_alignof(type) (sizeof (type)) #else # if PNG_ALIGN_TYPE == PNG_ALIGN_OFFSET # define png_alignof(type) offsetof(struct{char c; type t;}, t) # else # if PNG_ALIGN_TYPE == PNG_ALIGN_ALWAYS # define png_alignof(type) (1) # endif /* Else leave png_alignof undefined to prevent use thereof */ # endif #endif /* This implicitly assumes alignment is always to a power of 2. */ #ifdef png_alignof # define png_isaligned(ptr, type)\ ((((const char*)ptr-(const char*)0) & (png_alignof(type)-1)) == 0) #else # define png_isaligned(ptr, type) 0 #endif /* End of memory model/platform independent support */ /* End of 1.5.0beta36 move from pngconf.h */ /* CONSTANTS and UTILITY MACROS * These are used internally by libpng and not exposed in the API */ /* Various modes of operation. Note that after an init, mode is set to * zero automatically when the structure is created. Three of these * are defined in png.h because they need to be visible to applications * that call png_set_unknown_chunk(). */ /* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */ /* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */ #define PNG_HAVE_IDAT 0x04 /* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */ #define PNG_HAVE_IEND 0x10 /* 0x20 (unused) */ /* 0x40 (unused) */ /* 0x80 (unused) */ #define PNG_HAVE_CHUNK_HEADER 0x100 #define PNG_WROTE_tIME 0x200 #define PNG_WROTE_INFO_BEFORE_PLTE 0x400 #define PNG_BACKGROUND_IS_GRAY 0x800 #define PNG_HAVE_PNG_SIGNATURE 0x1000 #define PNG_HAVE_CHUNK_AFTER_IDAT 0x2000 /* Have another chunk after IDAT */ /* 0x4000 (unused) */ #define PNG_IS_READ_STRUCT 0x8000 /* Else is a write struct */ /* Flags for the transformations the PNG library does on the image data */ #define PNG_BGR 0x0001 #define PNG_INTERLACE 0x0002 #define PNG_PACK 0x0004 #define PNG_SHIFT 0x0008 #define PNG_SWAP_BYTES 0x0010 #define PNG_INVERT_MONO 0x0020 #define PNG_QUANTIZE 0x0040 #define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */ #define PNG_BACKGROUND_EXPAND 0x0100 #define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */ #define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */ #define PNG_RGBA 0x0800 #define PNG_EXPAND 0x1000 #define PNG_GAMMA 0x2000 #define PNG_GRAY_TO_RGB 0x4000 #define PNG_FILLER 0x8000 #define PNG_PACKSWAP 0x10000 #define PNG_SWAP_ALPHA 0x20000 #define PNG_STRIP_ALPHA 0x40000 #define PNG_INVERT_ALPHA 0x80000 #define PNG_USER_TRANSFORM 0x100000 #define PNG_RGB_TO_GRAY_ERR 0x200000 #define PNG_RGB_TO_GRAY_WARN 0x400000 #define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */ #define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */ #define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */ #define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */ #define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */ /* 0x8000000 unused */ /* 0x10000000 unused */ /* 0x20000000 unused */ /* 0x40000000 unused */ /* Flags for png_create_struct */ #define PNG_STRUCT_PNG 0x0001 #define PNG_STRUCT_INFO 0x0002 /* Scaling factor for filter heuristic weighting calculations */ #define PNG_WEIGHT_FACTOR (1<<(PNG_WEIGHT_SHIFT)) #define PNG_COST_FACTOR (1<<(PNG_COST_SHIFT)) /* Flags for the png_ptr->flags rather than declaring a byte for each one */ #define PNG_FLAG_ZLIB_CUSTOM_STRATEGY 0x0001 #define PNG_FLAG_ZSTREAM_INITIALIZED 0x0002 /* Added to libpng-1.6.0 */ /* 0x0004 unused */ #define PNG_FLAG_ZSTREAM_ENDED 0x0008 /* Added to libpng-1.6.0 */ /* 0x0010 unused */ /* 0x0020 unused */ #define PNG_FLAG_ROW_INIT 0x0040 #define PNG_FLAG_FILLER_AFTER 0x0080 #define PNG_FLAG_CRC_ANCILLARY_USE 0x0100 #define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200 #define PNG_FLAG_CRC_CRITICAL_USE 0x0400 #define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800 #define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */ #define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */ #define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */ /* #define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000 */ /* #define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000 */ #define PNG_FLAG_LIBRARY_MISMATCH 0x20000 #define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000 #define PNG_FLAG_STRIP_ERROR_TEXT 0x80000 #define PNG_FLAG_BENIGN_ERRORS_WARN 0x100000 /* Added to libpng-1.4.0 */ #define PNG_FLAG_APP_WARNINGS_WARN 0x200000 /* Added to libpng-1.6.0 */ #define PNG_FLAG_APP_ERRORS_WARN 0x400000 /* Added to libpng-1.6.0 */ /* 0x800000 unused */ /* 0x1000000 unused */ /* 0x2000000 unused */ /* 0x4000000 unused */ /* 0x8000000 unused */ /* 0x10000000 unused */ /* 0x20000000 unused */ /* 0x40000000 unused */ #define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \ PNG_FLAG_CRC_ANCILLARY_NOWARN) #define PNG_FLAG_CRC_CRITICAL_MASK (PNG_FLAG_CRC_CRITICAL_USE | \ PNG_FLAG_CRC_CRITICAL_IGNORE) #define PNG_FLAG_CRC_MASK (PNG_FLAG_CRC_ANCILLARY_MASK | \ PNG_FLAG_CRC_CRITICAL_MASK) /* Save typing and make code easier to understand */ #define PNG_COLOR_DIST(c1, c2) (abs((int)((c1).red) - (int)((c2).red)) + \ abs((int)((c1).green) - (int)((c2).green)) + \ abs((int)((c1).blue) - (int)((c2).blue))) /* Added to libpng-1.6.0: scale a 16-bit value in the range 0..65535 to 0..255 * by dividing by 257 *with rounding*. This macro is exact for the given range. * See the discourse in pngrtran.c png_do_scale_16_to_8. The values in the * macro were established by experiment (modifying the added value). The macro * has a second variant that takes a value already scaled by 255 and divides by * 65535 - this has a maximum error of .502. Over the range 0..65535*65535 it * only gives off-by-one errors and only for 0.5% (1 in 200) of the values. */ #define PNG_DIV65535(v24) (((v24) + 32895) >> 16) #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255) /* Added to libpng-1.2.6 JB */ #define PNG_ROWBYTES(pixel_bits, width) \ ((pixel_bits) >= 8 ? \ ((png_size_t)(width) * (((png_size_t)(pixel_bits)) >> 3)) : \ (( ((png_size_t)(width) * ((png_size_t)(pixel_bits))) + 7) >> 3) ) /* PNG_OUT_OF_RANGE returns true if value is outside the range * ideal-delta..ideal+delta. Each argument is evaluated twice. * "ideal" and "delta" should be constants, normally simple * integers, "value" a variable. Added to libpng-1.2.6 JB */ #define PNG_OUT_OF_RANGE(value, ideal, delta) \ ( (value) < (ideal)-(delta) || (value) > (ideal)+(delta) ) /* Conversions between fixed and floating point, only defined if * required (to make sure the code doesn't accidentally use float * when it is supposedly disabled.) */ #ifdef PNG_FLOATING_POINT_SUPPORTED /* The floating point conversion can't overflow, though it can and * does lose accuracy relative to the original fixed point value. * In practice this doesn't matter because png_fixed_point only * stores numbers with very low precision. The png_ptr and s * arguments are unused by default but are there in case error * checking becomes a requirement. */ #define png_float(png_ptr, fixed, s) (.00001 * (fixed)) /* The fixed point conversion performs range checking and evaluates * its argument multiple times, so must be used with care. The * range checking uses the PNG specification values for a signed * 32 bit fixed point value except that the values are deliberately * rounded-to-zero to an integral value - 21474 (21474.83 is roughly * (2^31-1) * 100000). 's' is a string that describes the value being * converted. * * NOTE: this macro will raise a png_error if the range check fails, * therefore it is normally only appropriate to use this on values * that come from API calls or other sources where an out of range * error indicates a programming error, not a data error! * * NOTE: by default this is off - the macro is not used - because the * function call saves a lot of code. */ #ifdef PNG_FIXED_POINT_MACRO_SUPPORTED #define png_fixed(png_ptr, fp, s) ((fp) <= 21474 && (fp) >= -21474 ?\ ((png_fixed_point)(100000 * (fp))) : (png_fixed_error(png_ptr, s),0)) #endif /* else the corresponding function is defined below, inside the scope of the * cplusplus test. */ #endif /* Constants for known chunk types. If you need to add a chunk, define the name * here. For historical reasons these constants have the form png_; i.e. * the prefix is lower case. Please use decimal values as the parameters to * match the ISO PNG specification and to avoid relying on the C locale * interpretation of character values. * * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string * to be generated if required. * * PNG_32b correctly produces a value shifted by up to 24 bits, even on * architectures where (int) is only 16 bits. */ #define PNG_32b(b,s) ((png_uint_32)(b) << (s)) #define PNG_U32(b1,b2,b3,b4) \ (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0)) /* Constants for known chunk types. * * MAINTAINERS: If you need to add a chunk, define the name here. * For historical reasons these constants have the form png_; i.e. * the prefix is lower case. Please use decimal values as the parameters to * match the ISO PNG specification and to avoid relying on the C locale * interpretation of character values. Please keep the list sorted. * * Notice that PNG_U32 is used to define a 32-bit value for the 4 byte chunk * type. In fact the specification does not express chunk types this way, * however using a 32-bit value means that the chunk type can be read from the * stream using exactly the same code as used for a 32-bit unsigned value and * can be examined far more efficiently (using one arithmetic compare). * * Prior to 1.5.6 the chunk type constants were expressed as C strings. The * libpng API still uses strings for 'unknown' chunks and a macro, * PNG_STRING_FROM_CHUNK, allows a string to be generated if required. Notice * that for portable code numeric values must still be used; the string "IHDR" * is not portable and neither is PNG_U32('I', 'H', 'D', 'R'). * * In 1.7.0 the definitions will be made public in png.h to avoid having to * duplicate the same definitions in application code. */ #define png_IDAT PNG_U32( 73, 68, 65, 84) #define png_IEND PNG_U32( 73, 69, 78, 68) #define png_IHDR PNG_U32( 73, 72, 68, 82) #define png_PLTE PNG_U32( 80, 76, 84, 69) #define png_bKGD PNG_U32( 98, 75, 71, 68) #define png_cHRM PNG_U32( 99, 72, 82, 77) #define png_fRAc PNG_U32(102, 82, 65, 99) /* registered, not defined */ #define png_gAMA PNG_U32(103, 65, 77, 65) #define png_gIFg PNG_U32(103, 73, 70, 103) #define png_gIFt PNG_U32(103, 73, 70, 116) /* deprecated */ #define png_gIFx PNG_U32(103, 73, 70, 120) #define png_hIST PNG_U32(104, 73, 83, 84) #define png_iCCP PNG_U32(105, 67, 67, 80) #define png_iTXt PNG_U32(105, 84, 88, 116) #define png_oFFs PNG_U32(111, 70, 70, 115) #define png_pCAL PNG_U32(112, 67, 65, 76) #define png_pHYs PNG_U32(112, 72, 89, 115) #define png_sBIT PNG_U32(115, 66, 73, 84) #define png_sCAL PNG_U32(115, 67, 65, 76) #define png_sPLT PNG_U32(115, 80, 76, 84) #define png_sRGB PNG_U32(115, 82, 71, 66) #define png_sTER PNG_U32(115, 84, 69, 82) #define png_tEXt PNG_U32(116, 69, 88, 116) #define png_tIME PNG_U32(116, 73, 77, 69) #define png_tRNS PNG_U32(116, 82, 78, 83) #define png_zTXt PNG_U32(122, 84, 88, 116) /* The following will work on (signed char*) strings, whereas the get_uint_32 * macro will fail on top-bit-set values because of the sign extension. */ #define PNG_CHUNK_FROM_STRING(s)\ PNG_U32(0xff & (s)[0], 0xff & (s)[1], 0xff & (s)[2], 0xff & (s)[3]) /* This uses (char), not (png_byte) to avoid warnings on systems where (char) is * signed and the argument is a (char[]) This macro will fail miserably on * systems where (char) is more than 8 bits. */ #define PNG_STRING_FROM_CHUNK(s,c)\ (void)(((char*)(s))[0]=(char)(((c)>>24) & 0xff), \ ((char*)(s))[1]=(char)(((c)>>16) & 0xff),\ ((char*)(s))[2]=(char)(((c)>>8) & 0xff), \ ((char*)(s))[3]=(char)((c & 0xff))) /* Do the same but terminate with a null character. */ #define PNG_CSTRING_FROM_CHUNK(s,c)\ (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0) /* Test on flag values as defined in the spec (section 5.4): */ #define PNG_CHUNK_ANCILLARY(c) (1 & ((c) >> 29)) #define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLARY(c)) #define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21)) #define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13)) #define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5)) /* Gamma values (new at libpng-1.5.4): */ #define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */ #define PNG_GAMMA_MAC_INVERSE 65909 #define PNG_GAMMA_sRGB_INVERSE 45455 /* Almost everything below is C specific; the #defines above can be used in * non-C code (so long as it is C-preprocessed) the rest of this stuff cannot. */ #ifndef PNG_VERSION_INFO_ONLY #include "pngstruct.h" #include "pnginfo.h" /* Validate the include paths - the include path used to generate pnglibconf.h * must match that used in the build, or we must be using pnglibconf.h.prebuilt: */ #if PNG_ZLIB_VERNUM != 0 && PNG_ZLIB_VERNUM != ZLIB_VERNUM # error ZLIB_VERNUM != PNG_ZLIB_VERNUM \ "-I (include path) error: see the notes in pngpriv.h" /* This means that when pnglibconf.h was built the copy of zlib.h that it * used is not the same as the one being used here. Because the build of * libpng makes decisions to use inflateInit2 and inflateReset2 based on the * zlib version number and because this affects handling of certain broken * PNG files the -I directives must match. * * The most likely explanation is that you passed a -I in CFLAGS. This will * not work; all the preprocessor directories and in particular all the -I * directives must be in CPPFLAGS. */ #endif /* This is used for 16 bit gamma tables -- only the top level pointers are * const; this could be changed: */ typedef const png_uint_16p * png_const_uint_16pp; /* Added to libpng-1.5.7: sRGB conversion tables */ #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\ defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) #ifdef PNG_SIMPLIFIED_READ_SUPPORTED PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_table, [256]); /* Convert from an sRGB encoded value 0..255 to a 16-bit linear value, * 0..65535. This table gives the closest 16-bit answers (no errors). */ #endif PNG_INTERNAL_DATA(const png_uint_16, png_sRGB_base, [512]); PNG_INTERNAL_DATA(const png_byte, png_sRGB_delta, [512]); #define PNG_sRGB_FROM_LINEAR(linear) \ ((png_byte)(0xff & ((png_sRGB_base[(linear)>>15] \ + ((((linear) & 0x7fff)*png_sRGB_delta[(linear)>>15])>>12)) >> 8))) /* Given a value 'linear' in the range 0..255*65535 calculate the 8-bit sRGB * encoded value with maximum error 0.646365. Note that the input is not a * 16-bit value; it has been multiplied by 255! */ #endif /* SIMPLIFIED_READ/WRITE */ /* Inhibit C++ name-mangling for libpng functions but not for system calls. */ #ifdef __cplusplus extern "C" { #endif /* __cplusplus */ /* Internal functions; these are not exported from a DLL however because they * are used within several of the C source files they have to be C extern. * * All of these functions must be declared with PNG_INTERNAL_FUNCTION. */ /* Zlib support */ #define PNG_UNEXPECTED_ZLIB_RETURN (-7) PNG_INTERNAL_FUNCTION(void, png_zstream_error,(png_structrp png_ptr, int ret), PNG_EMPTY); /* Used by the zlib handling functions to ensure that z_stream::msg is always * set before they return. */ #ifdef PNG_WRITE_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_free_buffer_list,(png_structrp png_ptr, png_compression_bufferp *list),PNG_EMPTY); /* Free the buffer list used by the compressed write code. */ #endif #if defined(PNG_FLOATING_POINT_SUPPORTED) && \ !defined(PNG_FIXED_POINT_MACRO_SUPPORTED) && \ (defined(PNG_gAMA_SUPPORTED) || defined(PNG_cHRM_SUPPORTED) || \ defined(PNG_sCAL_SUPPORTED) || defined(PNG_READ_BACKGROUND_SUPPORTED) || \ defined(PNG_READ_RGB_TO_GRAY_SUPPORTED)) || \ (defined(PNG_sCAL_SUPPORTED) && \ defined(PNG_FLOATING_ARITHMETIC_SUPPORTED)) PNG_INTERNAL_FUNCTION(png_fixed_point,png_fixed,(png_const_structrp png_ptr, double fp, png_const_charp text),PNG_EMPTY); #endif /* Check the user version string for compatibility, returns false if the version * numbers aren't compatible. */ PNG_INTERNAL_FUNCTION(int,png_user_version_check,(png_structrp png_ptr, png_const_charp user_png_ver),PNG_EMPTY); /* Internal base allocator - no messages, NULL on failure to allocate. This * does, however, call the application provided allocator and that could call * png_error (although that would be a bug in the application implementation.) */ PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_base,(png_const_structrp png_ptr, png_alloc_size_t size),PNG_ALLOCATED); #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\ defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED) /* Internal array allocator, outputs no error or warning messages on failure, * just returns NULL. */ PNG_INTERNAL_FUNCTION(png_voidp,png_malloc_array,(png_const_structrp png_ptr, int nelements, size_t element_size),PNG_ALLOCATED); /* The same but an existing array is extended by add_elements. This function * also memsets the new elements to 0 and copies the old elements. The old * array is not freed or altered. */ PNG_INTERNAL_FUNCTION(png_voidp,png_realloc_array,(png_const_structrp png_ptr, png_const_voidp array, int old_elements, int add_elements, size_t element_size),PNG_ALLOCATED); #endif /* text, sPLT or unknown chunks */ /* Magic to create a struct when there is no struct to call the user supplied * memory allocators. Because error handling has not been set up the memory * handlers can't safely call png_error, but this is an obscure and undocumented * restriction so libpng has to assume that the 'free' handler, at least, might * call png_error. */ PNG_INTERNAL_FUNCTION(png_structp,png_create_png_struct, (png_const_charp user_png_ver, png_voidp error_ptr, png_error_ptr error_fn, png_error_ptr warn_fn, png_voidp mem_ptr, png_malloc_ptr malloc_fn, png_free_ptr free_fn),PNG_ALLOCATED); /* Free memory from internal libpng struct */ PNG_INTERNAL_FUNCTION(void,png_destroy_png_struct,(png_structrp png_ptr), PNG_EMPTY); /* Free an allocated jmp_buf (always succeeds) */ PNG_INTERNAL_FUNCTION(void,png_free_jmpbuf,(png_structrp png_ptr),PNG_EMPTY); /* Function to allocate memory for zlib. PNGAPI is disallowed. */ PNG_INTERNAL_FUNCTION(voidpf,png_zalloc,(voidpf png_ptr, uInt items, uInt size), PNG_ALLOCATED); /* Function to free memory for zlib. PNGAPI is disallowed. */ PNG_INTERNAL_FUNCTION(void,png_zfree,(voidpf png_ptr, voidpf ptr),PNG_EMPTY); /* Next four functions are used internally as callbacks. PNGCBAPI is required * but not PNG_EXPORT. PNGAPI added at libpng version 1.2.3, changed to * PNGCBAPI at 1.5.0 */ PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr, png_bytep data, png_size_t length),PNG_EMPTY); #ifdef PNG_PROGRESSIVE_READ_SUPPORTED PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_push_fill_buffer,(png_structp png_ptr, png_bytep buffer, png_size_t length),PNG_EMPTY); #endif PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_write_data,(png_structp png_ptr, png_bytep data, png_size_t length),PNG_EMPTY); #ifdef PNG_WRITE_FLUSH_SUPPORTED # ifdef PNG_STDIO_SUPPORTED PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr), PNG_EMPTY); # endif #endif /* Reset the CRC variable */ PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr),PNG_EMPTY); /* Write the "data" buffer to whatever output you are using */ PNG_INTERNAL_FUNCTION(void,png_write_data,(png_structrp png_ptr, png_const_bytep data, png_size_t length),PNG_EMPTY); /* Read and check the PNG file signature */ PNG_INTERNAL_FUNCTION(void,png_read_sig,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); /* Read the chunk header (length + type name) */ PNG_INTERNAL_FUNCTION(png_uint_32,png_read_chunk_header,(png_structrp png_ptr), PNG_EMPTY); /* Read data from whatever input you are using into the "data" buffer */ PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_bytep data, png_size_t length),PNG_EMPTY); /* Read bytes into buf, and update png_ptr->crc */ PNG_INTERNAL_FUNCTION(void,png_crc_read,(png_structrp png_ptr, png_bytep buf, png_uint_32 length),PNG_EMPTY); /* Read "skip" bytes, read the file crc, and (optionally) verify png_ptr->crc */ PNG_INTERNAL_FUNCTION(int,png_crc_finish,(png_structrp png_ptr, png_uint_32 skip),PNG_EMPTY); /* Read the CRC from the file and compare it to the libpng calculated CRC */ PNG_INTERNAL_FUNCTION(int,png_crc_error,(png_structrp png_ptr),PNG_EMPTY); /* Calculate the CRC over a section of data. Note that we are only * passing a maximum of 64K on systems that have this as a memory limit, * since this is the maximum buffer size we can specify. */ PNG_INTERNAL_FUNCTION(void,png_calculate_crc,(png_structrp png_ptr, png_const_bytep ptr, png_size_t length),PNG_EMPTY); #ifdef PNG_WRITE_FLUSH_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_flush,(png_structrp png_ptr),PNG_EMPTY); #endif /* Write various chunks */ /* Write the IHDR chunk, and update the png_struct with the necessary * information. */ PNG_INTERNAL_FUNCTION(void,png_write_IHDR,(png_structrp png_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, int compression_method, int filter_method, int interlace_method),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_write_PLTE,(png_structrp png_ptr, png_const_colorp palette, png_uint_32 num_pal),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_compress_IDAT,(png_structrp png_ptr, png_const_bytep row_data, png_alloc_size_t row_data_length, int flush), PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_write_IEND,(png_structrp png_ptr),PNG_EMPTY); #ifdef PNG_WRITE_gAMA_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_gAMA_fixed,(png_structrp png_ptr, png_fixed_point file_gamma),PNG_EMPTY); #endif #ifdef PNG_WRITE_sBIT_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_sBIT,(png_structrp png_ptr, png_const_color_8p sbit, int color_type),PNG_EMPTY); #endif #ifdef PNG_WRITE_cHRM_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_cHRM_fixed,(png_structrp png_ptr, const png_xy *xy), PNG_EMPTY); /* The xy value must have been previously validated */ #endif #ifdef PNG_WRITE_sRGB_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_sRGB,(png_structrp png_ptr, int intent),PNG_EMPTY); #endif #ifdef PNG_WRITE_iCCP_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_iCCP,(png_structrp png_ptr, png_const_charp name, png_const_bytep profile), PNG_EMPTY); /* The profile must have been previously validated for correctness, the * length comes from the first four bytes. Only the base, deflate, * compression is supported. */ #endif #ifdef PNG_WRITE_sPLT_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_sPLT,(png_structrp png_ptr, png_const_sPLT_tp palette),PNG_EMPTY); #endif #ifdef PNG_WRITE_tRNS_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_tRNS,(png_structrp png_ptr, png_const_bytep trans, png_const_color_16p values, int number, int color_type),PNG_EMPTY); #endif #ifdef PNG_WRITE_bKGD_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_bKGD,(png_structrp png_ptr, png_const_color_16p values, int color_type),PNG_EMPTY); #endif #ifdef PNG_WRITE_hIST_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_hIST,(png_structrp png_ptr, png_const_uint_16p hist, int num_hist),PNG_EMPTY); #endif /* Chunks that have keywords */ #ifdef PNG_WRITE_tEXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_tEXt,(png_structrp png_ptr, png_const_charp key, png_const_charp text, png_size_t text_len),PNG_EMPTY); #endif #ifdef PNG_WRITE_zTXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_zTXt,(png_structrp png_ptr, png_const_charp key, png_const_charp text, int compression),PNG_EMPTY); #endif #ifdef PNG_WRITE_iTXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_iTXt,(png_structrp png_ptr, int compression, png_const_charp key, png_const_charp lang, png_const_charp lang_key, png_const_charp text),PNG_EMPTY); #endif #ifdef PNG_TEXT_SUPPORTED /* Added at version 1.0.14 and 1.2.4 */ PNG_INTERNAL_FUNCTION(int,png_set_text_2,(png_const_structrp png_ptr, png_inforp info_ptr, png_const_textp text_ptr, int num_text),PNG_EMPTY); #endif #ifdef PNG_WRITE_oFFs_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_oFFs,(png_structrp png_ptr, png_int_32 x_offset, png_int_32 y_offset, int unit_type),PNG_EMPTY); #endif #ifdef PNG_WRITE_pCAL_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_pCAL,(png_structrp png_ptr, png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams, png_const_charp units, png_charpp params),PNG_EMPTY); #endif #ifdef PNG_WRITE_pHYs_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_pHYs,(png_structrp png_ptr, png_uint_32 x_pixels_per_unit, png_uint_32 y_pixels_per_unit, int unit_type),PNG_EMPTY); #endif #ifdef PNG_WRITE_tIME_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_tIME,(png_structrp png_ptr, png_const_timep mod_time),PNG_EMPTY); #endif #ifdef PNG_WRITE_sCAL_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_write_sCAL_s,(png_structrp png_ptr, int unit, png_const_charp width, png_const_charp height),PNG_EMPTY); #endif /* Called when finished processing a row of data */ PNG_INTERNAL_FUNCTION(void,png_write_finish_row,(png_structrp png_ptr), PNG_EMPTY); /* Internal use only. Called before first row of data */ PNG_INTERNAL_FUNCTION(void,png_write_start_row,(png_structrp png_ptr), PNG_EMPTY); /* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an * array of png_ptr->width pixels. If the image is not interlaced or this * is the final pass this just does a memcpy, otherwise the "display" flag * is used to determine whether to copy pixels that are not in the current pass. * * Because 'png_do_read_interlace' (below) replicates pixels this allows this * function to achieve the documented 'blocky' appearance during interlaced read * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row' * are not changed if they are not in the current pass, when display is 0. * * 'display' must be 0 or 1, otherwise the memcpy will be done regardless. * * The API always reads from the png_struct row buffer and always assumes that * it is full width (png_do_read_interlace has already been called.) * * This function is only ever used to write to row buffers provided by the * caller of the relevant libpng API and the row must have already been * transformed by the read transformations. * * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed * bitmasks for use within the code, otherwise runtime generated masks are used. * The default is compile time masks. */ #ifndef PNG_USE_COMPILE_TIME_MASKS # define PNG_USE_COMPILE_TIME_MASKS 1 #endif PNG_INTERNAL_FUNCTION(void,png_combine_row,(png_const_structrp png_ptr, png_bytep row, int display),PNG_EMPTY); #ifdef PNG_READ_INTERLACING_SUPPORTED /* Expand an interlaced row: the 'row_info' describes the pass data that has * been read in and must correspond to the pixels in 'row', the pixels are * expanded (moved apart) in 'row' to match the final layout, when doing this * the pixels are *replicated* to the intervening space. This is essential for * the correct operation of png_combine_row, above. */ PNG_INTERNAL_FUNCTION(void,png_do_read_interlace,(png_row_infop row_info, png_bytep row, int pass, png_uint_32 transformations),PNG_EMPTY); #endif /* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */ #ifdef PNG_WRITE_INTERLACING_SUPPORTED /* Grab pixels out of a row for an interlaced pass */ PNG_INTERNAL_FUNCTION(void,png_do_write_interlace,(png_row_infop row_info, png_bytep row, int pass),PNG_EMPTY); #endif /* Unfilter a row: check the filter value before calling this, there is no point * calling it for PNG_FILTER_VALUE_NONE. */ PNG_INTERNAL_FUNCTION(void,png_read_filter_row,(png_structrp pp, png_row_infop row_info, png_bytep row, png_const_bytep prev_row, int filter),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_up_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub3_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_sub4_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg3_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_avg4_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth3_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_filter_row_paeth4_neon,(png_row_infop row_info, png_bytep row, png_const_bytep prev_row),PNG_EMPTY); /* Choose the best filter to use and filter the row data */ PNG_INTERNAL_FUNCTION(void,png_write_find_filter,(png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY); #ifdef PNG_SEQUENTIAL_READ_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_read_IDAT_data,(png_structrp png_ptr, png_bytep output, png_alloc_size_t avail_out),PNG_EMPTY); /* Read 'avail_out' bytes of data from the IDAT stream. If the output buffer * is NULL the function checks, instead, for the end of the stream. In this * case a benign error will be issued if the stream end is not found or if * extra data has to be consumed. */ PNG_INTERNAL_FUNCTION(void,png_read_finish_IDAT,(png_structrp png_ptr), PNG_EMPTY); /* This cleans up when the IDAT LZ stream does not end when the last image * byte is read; there is still some pending input. */ PNG_INTERNAL_FUNCTION(void,png_read_finish_row,(png_structrp png_ptr), PNG_EMPTY); /* Finish a row while reading, dealing with interlacing passes, etc. */ #endif /* SEQUENTIAL_READ */ /* Initialize the row buffers, etc. */ PNG_INTERNAL_FUNCTION(void,png_read_start_row,(png_structrp png_ptr),PNG_EMPTY); #ifdef PNG_READ_TRANSFORMS_SUPPORTED /* Optional call to update the users info structure */ PNG_INTERNAL_FUNCTION(void,png_read_transform_info,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); #endif /* Shared transform functions, defined in pngtran.c */ #if defined(PNG_WRITE_FILLER_SUPPORTED) || \ defined(PNG_READ_STRIP_ALPHA_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_do_strip_channel,(png_row_infop row_info, png_bytep row, int at_start),PNG_EMPTY); #endif #ifdef PNG_16BIT_SUPPORTED #if defined(PNG_READ_SWAP_SUPPORTED) || defined(PNG_WRITE_SWAP_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_do_swap,(png_row_infop row_info, png_bytep row),PNG_EMPTY); #endif #endif #if defined(PNG_READ_PACKSWAP_SUPPORTED) || \ defined(PNG_WRITE_PACKSWAP_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_do_packswap,(png_row_infop row_info, png_bytep row),PNG_EMPTY); #endif #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_row_infop row_info, png_bytep row),PNG_EMPTY); #endif #if defined(PNG_READ_BGR_SUPPORTED) || defined(PNG_WRITE_BGR_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_do_bgr,(png_row_infop row_info, png_bytep row),PNG_EMPTY); #endif /* The following decodes the appropriate chunks, and does error correction, * then calls the appropriate callback for the chunk if it is valid. */ /* Decode the IHDR chunk */ PNG_INTERNAL_FUNCTION(void,png_handle_IHDR,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_handle_PLTE,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_handle_IEND,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #ifdef PNG_READ_bKGD_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_bKGD,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_cHRM_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_cHRM,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_gAMA_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_gAMA,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_hIST_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_hIST,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_iCCP_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_iCCP,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif /* READ_iCCP */ #ifdef PNG_READ_iTXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_iTXt,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_oFFs_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_oFFs,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_pCAL_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_pCAL,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_pHYs_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_pHYs,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_sBIT_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_sBIT,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_sCAL_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_sCAL,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_sPLT_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_sPLT,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif /* READ_sPLT */ #ifdef PNG_READ_sRGB_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_sRGB,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_tEXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_tEXt,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_tIME_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_tIME,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_tRNS_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_tRNS,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif #ifdef PNG_READ_zTXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_handle_zTXt,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); #endif PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length, int keep),PNG_EMPTY); /* This is the function that gets called for unknown chunks. The 'keep' * argument is either non-zero for a known chunk that has been set to be * handled as unknown or zero for an unknown chunk. By default the function * just skips the chunk or errors out if it is critical. */ #if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) ||\ defined(PNG_HANDLE_AS_UNKNOWN_SUPPORTED) PNG_INTERNAL_FUNCTION(int,png_chunk_unknown_handling, (png_const_structrp png_ptr, png_uint_32 chunk_name),PNG_EMPTY); /* Exactly as the API png_handle_as_unknown() except that the argument is a * 32-bit chunk name, not a string. */ #endif /* READ_UNKNOWN_CHUNKS || HANDLE_AS_UNKNOWN */ /* Handle the transformations for reading and writing */ #ifdef PNG_READ_TRANSFORMS_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_do_read_transformations,(png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY); #endif #ifdef PNG_WRITE_TRANSFORMS_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_do_write_transformations,(png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY); #endif #ifdef PNG_READ_TRANSFORMS_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_init_read_transformations,(png_structrp png_ptr), PNG_EMPTY); #endif #ifdef PNG_PROGRESSIVE_READ_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_push_read_chunk,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_read_sig,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_check_crc,(png_structrp png_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_crc_skip,(png_structrp png_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_crc_finish,(png_structrp png_ptr), PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_save_buffer,(png_structrp png_ptr), PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_restore_buffer,(png_structrp png_ptr, png_bytep buffer, png_size_t buffer_length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_read_IDAT,(png_structrp png_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_process_IDAT_data,(png_structrp png_ptr, png_bytep buffer, png_size_t buffer_length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_process_row,(png_structrp png_ptr), PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_handle_unknown,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_have_info,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_have_end,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_have_row,(png_structrp png_ptr, png_bytep row),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_read_end,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_process_some_data,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_read_push_finish_row,(png_structrp png_ptr), PNG_EMPTY); # ifdef PNG_READ_tEXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_push_handle_tEXt,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_read_tEXt,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); # endif # ifdef PNG_READ_zTXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_push_handle_zTXt,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_read_zTXt,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); # endif # ifdef PNG_READ_iTXt_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_push_handle_iTXt,(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_push_read_iTXt,(png_structrp png_ptr, png_inforp info_ptr),PNG_EMPTY); # endif #endif /* PROGRESSIVE_READ */ /* Added at libpng version 1.6.0 */ #ifdef PNG_GAMMA_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_colorspace_set_gamma,(png_const_structrp png_ptr, png_colorspacerp colorspace, png_fixed_point gAMA), PNG_EMPTY); /* Set the colorspace gamma with a value provided by the application or by * the gAMA chunk on read. The value will override anything set by an ICC * profile. */ PNG_INTERNAL_FUNCTION(void,png_colorspace_sync_info,(png_const_structrp png_ptr, png_inforp info_ptr), PNG_EMPTY); /* Synchronize the info 'valid' flags with the colorspace */ PNG_INTERNAL_FUNCTION(void,png_colorspace_sync,(png_const_structrp png_ptr, png_inforp info_ptr), PNG_EMPTY); /* Copy the png_struct colorspace to the info_struct and call the above to * synchronize the flags. Checks for NULL info_ptr and does nothing. */ #endif /* Added at libpng version 1.4.0 */ #ifdef PNG_COLORSPACE_SUPPORTED /* These internal functions are for maintaining the colorspace structure within * a png_info or png_struct (or, indeed, both). */ PNG_INTERNAL_FUNCTION(int,png_colorspace_set_chromaticities, (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_xy *xy, int preferred), PNG_EMPTY); PNG_INTERNAL_FUNCTION(int,png_colorspace_set_endpoints, (png_const_structrp png_ptr, png_colorspacerp colorspace, const png_XYZ *XYZ, int preferred), PNG_EMPTY); #ifdef PNG_sRGB_SUPPORTED PNG_INTERNAL_FUNCTION(int,png_colorspace_set_sRGB,(png_const_structrp png_ptr, png_colorspacerp colorspace, int intent), PNG_EMPTY); /* This does set the colorspace gAMA and cHRM values too, but doesn't set the * flags to write them, if it returns false there was a problem and an error * message has already been output (but the colorspace may still need to be * synced to record the invalid flag). */ #endif /* sRGB */ #ifdef PNG_iCCP_SUPPORTED PNG_INTERNAL_FUNCTION(int,png_colorspace_set_ICC,(png_const_structrp png_ptr, png_colorspacerp colorspace, png_const_charp name, png_uint_32 profile_length, png_const_bytep profile, int color_type), PNG_EMPTY); /* The 'name' is used for information only */ /* Routines for checking parts of an ICC profile. */ PNG_INTERNAL_FUNCTION(int,png_icc_check_length,(png_const_structrp png_ptr, png_colorspacerp colorspace, png_const_charp name, png_uint_32 profile_length), PNG_EMPTY); PNG_INTERNAL_FUNCTION(int,png_icc_check_header,(png_const_structrp png_ptr, png_colorspacerp colorspace, png_const_charp name, png_uint_32 profile_length, png_const_bytep profile /* first 132 bytes only */, int color_type), PNG_EMPTY); PNG_INTERNAL_FUNCTION(int,png_icc_check_tag_table,(png_const_structrp png_ptr, png_colorspacerp colorspace, png_const_charp name, png_uint_32 profile_length, png_const_bytep profile /* header plus whole tag table */), PNG_EMPTY); #ifdef PNG_sRGB_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_icc_set_sRGB,( png_const_structrp png_ptr, png_colorspacerp colorspace, png_const_bytep profile, uLong adler), PNG_EMPTY); /* 'adler' is the Adler32 checksum of the uncompressed profile data. It may * be zero to indicate that it is not available. It is used, if provided, * as a fast check on the profile when checking to see if it is sRGB. */ #endif #endif /* iCCP */ #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_colorspace_set_rgb_coefficients, (png_structrp png_ptr), PNG_EMPTY); /* Set the rgb_to_gray coefficients from the colorspace Y values */ #endif /* READ_RGB_TO_GRAY */ #endif /* COLORSPACE */ /* Added at libpng version 1.4.0 */ PNG_INTERNAL_FUNCTION(void,png_check_IHDR,(png_const_structrp png_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, int interlace_type, int compression_type, int filter_type),PNG_EMPTY); /* Added at libpng version 1.5.10 */ #if defined(PNG_READ_CHECK_FOR_INVALID_INDEX_SUPPORTED) || \ defined(PNG_WRITE_CHECK_FOR_INVALID_INDEX_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_do_check_palette_indexes, (png_structrp png_ptr, png_row_infop row_info),PNG_EMPTY); #endif #if defined(PNG_FLOATING_POINT_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED) PNG_INTERNAL_FUNCTION(void,png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN); #endif /* Puts 'string' into 'buffer' at buffer[pos], taking care never to overwrite * the end. Always leaves the buffer nul terminated. Never errors out (and * there is no error code.) */ PNG_INTERNAL_FUNCTION(size_t,png_safecat,(png_charp buffer, size_t bufsize, size_t pos, png_const_charp string),PNG_EMPTY); /* Various internal functions to handle formatted warning messages, currently * only implemented for warnings. */ #if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED) /* Utility to dump an unsigned value into a buffer, given a start pointer and * and end pointer (which should point just *beyond* the end of the buffer!) * Returns the pointer to the start of the formatted string. This utility only * does unsigned values. */ PNG_INTERNAL_FUNCTION(png_charp,png_format_number,(png_const_charp start, png_charp end, int format, png_alloc_size_t number),PNG_EMPTY); /* Convenience macro that takes an array: */ #define PNG_FORMAT_NUMBER(buffer,format,number) \ png_format_number(buffer, buffer + (sizeof buffer), format, number) /* Suggested size for a number buffer (enough for 64 bits and a sign!) */ #define PNG_NUMBER_BUFFER_SIZE 24 /* These are the integer formats currently supported, the name is formed from * the standard printf(3) format string. */ #define PNG_NUMBER_FORMAT_u 1 /* chose unsigned API! */ #define PNG_NUMBER_FORMAT_02u 2 #define PNG_NUMBER_FORMAT_d 1 /* chose signed API! */ #define PNG_NUMBER_FORMAT_02d 2 #define PNG_NUMBER_FORMAT_x 3 #define PNG_NUMBER_FORMAT_02x 4 #define PNG_NUMBER_FORMAT_fixed 5 /* choose the signed API */ #endif #ifdef PNG_WARNINGS_SUPPORTED /* New defines and members adding in libpng-1.5.4 */ # define PNG_WARNING_PARAMETER_SIZE 32 # define PNG_WARNING_PARAMETER_COUNT 8 /* Maximum 9; see pngerror.c */ /* An l-value of this type has to be passed to the APIs below to cache the * values of the parameters to a formatted warning message. */ typedef char png_warning_parameters[PNG_WARNING_PARAMETER_COUNT][ PNG_WARNING_PARAMETER_SIZE]; PNG_INTERNAL_FUNCTION(void,png_warning_parameter,(png_warning_parameters p, int number, png_const_charp string),PNG_EMPTY); /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters, * including the trailing '\0'. */ PNG_INTERNAL_FUNCTION(void,png_warning_parameter_unsigned, (png_warning_parameters p, int number, int format, png_alloc_size_t value), PNG_EMPTY); /* Use png_alloc_size_t because it is an unsigned type as big as any we * need to output. Use the following for a signed value. */ PNG_INTERNAL_FUNCTION(void,png_warning_parameter_signed, (png_warning_parameters p, int number, int format, png_int_32 value), PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_formatted_warning,(png_const_structrp png_ptr, png_warning_parameters p, png_const_charp message),PNG_EMPTY); /* 'message' follows the X/Open approach of using @1, @2 to insert * parameters previously supplied using the above functions. Errors in * specifying the parameters will simply result in garbage substitutions. */ #endif #ifdef PNG_BENIGN_ERRORS_SUPPORTED /* Application errors (new in 1.6); use these functions (declared below) for * errors in the parameters or order of API function calls on read. The * 'warning' should be used for an error that can be handled completely; the * 'error' for one which can be handled safely but which may lose application * information or settings. * * By default these both result in a png_error call prior to release, while in a * released version the 'warning' is just a warning. However if the application * explicitly disables benign errors (explicitly permitting the code to lose * information) they both turn into warnings. * * If benign errors aren't supported they end up as the corresponding base call * (png_warning or png_error.) */ PNG_INTERNAL_FUNCTION(void,png_app_warning,(png_const_structrp png_ptr, png_const_charp message),PNG_EMPTY); /* The application provided invalid parameters to an API function or called * an API function at the wrong time, libpng can completely recover. */ PNG_INTERNAL_FUNCTION(void,png_app_error,(png_const_structrp png_ptr, png_const_charp message),PNG_EMPTY); /* As above but libpng will ignore the call, or attempt some other partial * recovery from the error. */ #else # define png_app_warning(pp,s) png_warning(pp,s) # define png_app_error(pp,s) png_error(pp,s) #endif PNG_INTERNAL_FUNCTION(void,png_chunk_report,(png_const_structrp png_ptr, png_const_charp message, int error),PNG_EMPTY); /* Report a recoverable issue in chunk data. On read this is used to report * a problem found while reading a particular chunk and the * png_chunk_benign_error or png_chunk_warning function is used as * appropriate. On write this is used to report an error that comes from * data set via an application call to a png_set_ API and png_app_error or * png_app_warning is used as appropriate. * * The 'error' parameter must have one of the following values: */ #define PNG_CHUNK_WARNING 0 /* never an error */ #define PNG_CHUNK_WRITE_ERROR 1 /* an error only on write */ #define PNG_CHUNK_ERROR 2 /* always an error */ /* ASCII to FP interfaces, currently only implemented if sCAL * support is required. */ #if defined(PNG_sCAL_SUPPORTED) /* MAX_DIGITS is actually the maximum number of characters in an sCAL * width or height, derived from the precision (number of significant * digits - a build time settable option) and assumptions about the * maximum ridiculous exponent. */ #define PNG_sCAL_MAX_DIGITS (PNG_sCAL_PRECISION+1/*.*/+1/*E*/+10/*exponent*/) #ifdef PNG_FLOATING_POINT_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_ascii_from_fp,(png_const_structrp png_ptr, png_charp ascii, png_size_t size, double fp, unsigned int precision), PNG_EMPTY); #endif /* FLOATING_POINT */ #ifdef PNG_FIXED_POINT_SUPPORTED PNG_INTERNAL_FUNCTION(void,png_ascii_from_fixed,(png_const_structrp png_ptr, png_charp ascii, png_size_t size, png_fixed_point fp),PNG_EMPTY); #endif /* FIXED_POINT */ #endif /* sCAL */ #if defined(PNG_sCAL_SUPPORTED) || defined(PNG_pCAL_SUPPORTED) /* An internal API to validate the format of a floating point number. * The result is the index of the next character. If the number is * not valid it will be the index of a character in the supposed number. * * The format of a number is defined in the PNG extensions specification * and this API is strictly conformant to that spec, not anyone elses! * * The format as a regular expression is: * * [+-]?[0-9]+.?([Ee][+-]?[0-9]+)? * * or: * * [+-]?.[0-9]+(.[0-9]+)?([Ee][+-]?[0-9]+)? * * The complexity is that either integer or fraction must be present and the * fraction is permitted to have no digits only if the integer is present. * * NOTE: The dangling E problem. * There is a PNG valid floating point number in the following: * * PNG floating point numbers are not greedy. * * Working this out requires *TWO* character lookahead (because of the * sign), the parser does not do this - it will fail at the 'r' - this * doesn't matter for PNG sCAL chunk values, but it requires more care * if the value were ever to be embedded in something more complex. Use * ANSI-C strtod if you need the lookahead. */ /* State table for the parser. */ #define PNG_FP_INTEGER 0 /* before or in integer */ #define PNG_FP_FRACTION 1 /* before or in fraction */ #define PNG_FP_EXPONENT 2 /* before or in exponent */ #define PNG_FP_STATE 3 /* mask for the above */ #define PNG_FP_SAW_SIGN 4 /* Saw +/- in current state */ #define PNG_FP_SAW_DIGIT 8 /* Saw a digit in current state */ #define PNG_FP_SAW_DOT 16 /* Saw a dot in current state */ #define PNG_FP_SAW_E 32 /* Saw an E (or e) in current state */ #define PNG_FP_SAW_ANY 60 /* Saw any of the above 4 */ /* These three values don't affect the parser. They are set but not used. */ #define PNG_FP_WAS_VALID 64 /* Preceding substring is a valid fp number */ #define PNG_FP_NEGATIVE 128 /* A negative number, including "-0" */ #define PNG_FP_NONZERO 256 /* A non-zero value */ #define PNG_FP_STICKY 448 /* The above three flags */ /* This is available for the caller to store in 'state' if required. Do not * call the parser after setting it (the parser sometimes clears it.) */ #define PNG_FP_INVALID 512 /* Available for callers as a distinct value */ /* Result codes for the parser (boolean - true meants ok, false means * not ok yet.) */ #define PNG_FP_MAYBE 0 /* The number may be valid in the future */ #define PNG_FP_OK 1 /* The number is valid */ /* Tests on the sticky non-zero and negative flags. To pass these checks * the state must also indicate that the whole number is valid - this is * achieved by testing PNG_FP_SAW_DIGIT (see the implementation for why this * is equivalent to PNG_FP_OK above.) */ #define PNG_FP_NZ_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NEGATIVE | PNG_FP_NONZERO) /* NZ_MASK: the string is valid and a non-zero negative value */ #define PNG_FP_Z_MASK (PNG_FP_SAW_DIGIT | PNG_FP_NONZERO) /* Z MASK: the string is valid and a non-zero value. */ /* PNG_FP_SAW_DIGIT: the string is valid. */ #define PNG_FP_IS_ZERO(state) (((state) & PNG_FP_Z_MASK) == PNG_FP_SAW_DIGIT) #define PNG_FP_IS_POSITIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_Z_MASK) #define PNG_FP_IS_NEGATIVE(state) (((state) & PNG_FP_NZ_MASK) == PNG_FP_NZ_MASK) /* The actual parser. This can be called repeatedly. It updates * the index into the string and the state variable (which must * be initialized to 0). It returns a result code, as above. There * is no point calling the parser any more if it fails to advance to * the end of the string - it is stuck on an invalid character (or * terminated by '\0'). * * Note that the pointer will consume an E or even an E+ and then leave * a 'maybe' state even though a preceding integer.fraction is valid. * The PNG_FP_WAS_VALID flag indicates that a preceding substring was * a valid number. It's possible to recover from this by calling * the parser again (from the start, with state 0) but with a string * that omits the last character (i.e. set the size to the index of * the problem character.) This has not been tested within libpng. */ PNG_INTERNAL_FUNCTION(int,png_check_fp_number,(png_const_charp string, png_size_t size, int *statep, png_size_tp whereami),PNG_EMPTY); /* This is the same but it checks a complete string and returns true * only if it just contains a floating point number. As of 1.5.4 this * function also returns the state at the end of parsing the number if * it was valid (otherwise it returns 0.) This can be used for testing * for negative or zero values using the sticky flag. */ PNG_INTERNAL_FUNCTION(int,png_check_fp_string,(png_const_charp string, png_size_t size),PNG_EMPTY); #endif /* pCAL || sCAL */ #if defined(PNG_GAMMA_SUPPORTED) ||\ defined(PNG_INCH_CONVERSIONS_SUPPORTED) || defined(PNG_READ_pHYs_SUPPORTED) /* Added at libpng version 1.5.0 */ /* This is a utility to provide a*times/div (rounded) and indicate * if there is an overflow. The result is a boolean - false (0) * for overflow, true (1) if no overflow, in which case *res * holds the result. */ PNG_INTERNAL_FUNCTION(int,png_muldiv,(png_fixed_point_p res, png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY); #endif #if defined(PNG_READ_GAMMA_SUPPORTED) || defined(PNG_INCH_CONVERSIONS_SUPPORTED) /* Same deal, but issue a warning on overflow and return 0. */ PNG_INTERNAL_FUNCTION(png_fixed_point,png_muldiv_warn, (png_const_structrp png_ptr, png_fixed_point a, png_int_32 multiplied_by, png_int_32 divided_by),PNG_EMPTY); #endif #ifdef PNG_GAMMA_SUPPORTED /* Calculate a reciprocal - used for gamma values. This returns * 0 if the argument is 0 in order to maintain an undefined value; * there are no warnings. */ PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal,(png_fixed_point a), PNG_EMPTY); #ifdef PNG_READ_GAMMA_SUPPORTED /* The same but gives a reciprocal of the product of two fixed point * values. Accuracy is suitable for gamma calculations but this is * not exact - use png_muldiv for that. Only required at present on read. */ PNG_INTERNAL_FUNCTION(png_fixed_point,png_reciprocal2,(png_fixed_point a, png_fixed_point b),PNG_EMPTY); #endif /* Return true if the gamma value is significantly different from 1.0 */ PNG_INTERNAL_FUNCTION(int,png_gamma_significant,(png_fixed_point gamma_value), PNG_EMPTY); #endif #ifdef PNG_READ_GAMMA_SUPPORTED /* Internal fixed point gamma correction. These APIs are called as * required to convert single values - they don't need to be fast, * they are not used when processing image pixel values. * * While the input is an 'unsigned' value it must actually be the * correct bit value - 0..255 or 0..65535 as required. */ PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_correct,(png_structrp png_ptr, unsigned int value, png_fixed_point gamma_value),PNG_EMPTY); PNG_INTERNAL_FUNCTION(png_uint_16,png_gamma_16bit_correct,(unsigned int value, png_fixed_point gamma_value),PNG_EMPTY); PNG_INTERNAL_FUNCTION(png_byte,png_gamma_8bit_correct,(unsigned int value, png_fixed_point gamma_value),PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_destroy_gamma_table,(png_structrp png_ptr), PNG_EMPTY); PNG_INTERNAL_FUNCTION(void,png_build_gamma_table,(png_structrp png_ptr, int bit_depth),PNG_EMPTY); #endif /* SIMPLIFIED READ/WRITE SUPPORT */ #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\ defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) /* The internal structure that png_image::opaque points to. */ typedef struct png_control { png_structp png_ptr; png_infop info_ptr; png_voidp error_buf; /* Always a jmp_buf at present. */ png_const_bytep memory; /* Memory buffer. */ png_size_t size; /* Size of the memory buffer. */ unsigned int for_write :1; /* Otherwise it is a read structure */ unsigned int owned_file :1; /* We own the file in io_ptr */ } png_control; /* Return the pointer to the jmp_buf from a png_control: necessary because C * does not reveal the type of the elements of jmp_buf. */ #ifdef __cplusplus # define png_control_jmp_buf(pc) (((jmp_buf*)((pc)->error_buf))[0]) #else # define png_control_jmp_buf(pc) ((pc)->error_buf) #endif /* Utility to safely execute a piece of libpng code catching and logging any * errors that might occur. Returns true on success, false on failure (either * of the function or as a result of a png_error.) */ PNG_INTERNAL_CALLBACK(void,png_safe_error,(png_structp png_ptr, png_const_charp error_message),PNG_NORETURN); #ifdef PNG_WARNINGS_SUPPORTED PNG_INTERNAL_CALLBACK(void,png_safe_warning,(png_structp png_ptr, png_const_charp warning_message),PNG_EMPTY); #else # define png_safe_warning 0/*dummy argument*/ #endif PNG_INTERNAL_FUNCTION(int,png_safe_execute,(png_imagep image, int (*function)(png_voidp), png_voidp arg),PNG_EMPTY); /* Utility to log an error; this also cleans up the png_image; the function * always returns 0 (false). */ PNG_INTERNAL_FUNCTION(int,png_image_error,(png_imagep image, png_const_charp error_message),PNG_EMPTY); #ifndef PNG_SIMPLIFIED_READ_SUPPORTED /* png_image_free is used by the write code but not exported */ PNG_INTERNAL_FUNCTION(void, png_image_free, (png_imagep image), PNG_EMPTY); #endif /* !SIMPLIFIED_READ */ #endif /* SIMPLIFIED READ/WRITE */ /* These are initialization functions for hardware specific PNG filter * optimizations; list these here then select the appropriate one at compile * time using the macro PNG_FILTER_OPTIMIZATIONS. If the macro is not defined * the generic code is used. */ #ifdef PNG_FILTER_OPTIMIZATIONS PNG_INTERNAL_FUNCTION(void, PNG_FILTER_OPTIMIZATIONS, (png_structp png_ptr, unsigned int bpp), PNG_EMPTY); /* Just declare the optimization that will be used */ #else /* List *all* the possible optimizations here - this branch is required if * the builder of libpng passes the definition of PNG_FILTER_OPTIMIZATIONS in * CFLAGS in place of CPPFLAGS *and* uses symbol prefixing. */ PNG_INTERNAL_FUNCTION(void, png_init_filter_functions_neon, (png_structp png_ptr, unsigned int bpp), PNG_EMPTY); #endif /* Maintainer: Put new private prototypes here ^ */ #include "pngdebug.h" #ifdef __cplusplus } #endif #endif /* PNG_VERSION_INFO_ONLY */ #endif /* PNGPRIV_H */