| |
| /* pngpriv.h - private declarations for use inside libpng |
| * |
| * Last changed in libpng 1.7.0 [(PENDING RELEASE)] |
| * Copyright (c) 1998-2002,2004,2006-2016 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 |
| /* Keep standard libraries at the top of this file */ |
| |
| /* Standard library headers not required by png.h: */ |
| # include <stdlib.h> |
| # include <string.h> |
| |
| /* For headers only required with some build configurations see the lines after |
| * pnglibconf.h is included! |
| */ |
| |
| #endif /* VERSION_INFO_ONLY */ |
| |
| #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 <config.h> |
| |
| /* 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 |
| |
| #ifndef PNG_VERSION_INFO_ONLY |
| /* Additional standard libaries required in certain cases, put only standard |
| * ANSI-C89 headers here. If not available, or non-functional, the problem |
| * should be fixed by writing a wrapper for the header and the file on your |
| * include path. |
| */ |
| #if defined(PNG_sCAL_SUPPORTED) && defined(PNG_FLOATING_POINT_SUPPORTED) |
| /* png.c requires the following ANSI-C constants if the conversion of |
| * floating point to ASCII is implemented therein: |
| * |
| * DBL_MIN_10_EXP Minimum negative integer such that 10^integer is a |
| * normalized (double) value. |
| * 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 <float.h> |
| #endif /* sCAL && FLOATING_POINT */ |
| |
| #if defined(PNG_FLOATING_ARITHMETIC_SUPPORTED) ||\ |
| defined(PNG_FLOATING_POINT_SUPPORTED) |
| /* ANSI-C90 math functions are required. Full compliance with the standard |
| * is probably not a requirement, but the functions must exist and be |
| * declared in <math.h> |
| */ |
| # include <math.h> |
| #endif /* FLOATING_ARITHMETIC || FLOATING_POINT */ |
| |
| #endif /* VERSION_INFO_ONLY */ |
| |
| /* 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 here to get the version info and other macros, pngstruct.h and |
| * pnginfo.h are included later under the protection of !PNG_VERSION_INFO_ONLY |
| */ |
| #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 |
| |
| /* This is a global switch to set the compilation for an installed system |
| * (a release build). It can be set for testing debug builds to ensure that |
| * they will compile when the build type is switched to RC or STABLE, the |
| * default is just to use PNG_LIBPNG_BUILD_BASE_TYPE. Set this in CPPFLAGS |
| * with either: |
| * |
| * -DPNG_RELEASE_BUILD Turns on the release compile path |
| * -DPNG_RELEASE_BUILD=0 Turns it off |
| * or in your pngusr.h with |
| * #define PNG_RELEASE_BUILD=1 Turns on the release compile path |
| * #define PNG_RELEASE_BUILD=0 Turns it off |
| */ |
| #ifndef PNG_RELEASE_BUILD |
| # define PNG_RELEASE_BUILD (PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC) |
| #endif |
| |
| /* General purpose macros avoid the need to put #if PNG_RELEASE_BUILD |
| * macro blocks around function declarations and definitions when the |
| * parameter number varies. Using these results in slightly cleaner code. |
| */ |
| #if PNG_RELEASE_BUILD |
| # define only_rel(text) text |
| # define only_deb(text) |
| # define param_rel(param) param, |
| # define param_deb(param) |
| #else |
| # define only_rel(text) |
| # define only_deb(text) text |
| # define param_rel(param) |
| # define param_deb(param) param, |
| #endif |
| |
| /* The affirm mechanism results in a minimal png_error() in released versions |
| * ('STABLE' versions) and a more descriptive PNG_ABORT in all other cases, |
| * when the "condition" is false (zero). If "condition" is true (nonzero), |
| * then the affirm mechanism does nothing. |
| * |
| * The PNG_RELEASE_BUILD macro, defined above, controls the behavior of |
| * 'affirm': if set to 1 affirm will call png_error (or png_err) rather than |
| * abort. The png_error text is the minimal (file location) text in this case, |
| * if it is produced. This flag indicates a STABLE (or RC) build. |
| * |
| * The macros rely on the naming convention throughout this code - png_ptr |
| * exists and is of type png_const_structrp or a compatible type - and the |
| * presence in each file of a uniquely defined macro PNG_SRC_FILE; a number |
| * indicating which file this is (this is to save space in released versions). |
| * |
| * 'affirm' is intended to look like the ANSI-C <assert.h> macro; note that |
| * this macro can coexist with the assert macro if <assert.h> is |
| * included. |
| * |
| * PNG_SRC_LINE is the position of the affirm macro. There are currently 15 |
| * main source files (4 bits) and the biggest (pngrtran.c) has more than 4095 |
| * lines (12 bits). However, to ensure the number will fit into 16-bits in the |
| * future and to allow hardware files to use affirm, the encoding is a bit-wise |
| * encoding based on the current number of lines. |
| * |
| * 'debug' is a version of 'affirm' that is completely removed from RELEASE |
| * builds. This is used when either an unexpected condition is completely |
| * handled or when it can't be handled even by png_error, for example after a |
| * memory overwrite. |
| * |
| * UNTESTED is used to mark code that has not been tested; it causes an assert |
| * if the code is executed and (therefore) tested. UNTESTED should not remain |
| * in release candidate code. |
| * |
| * PNG_AFFIRM_TEXT is set to 1 if affirm text should be produced, either |
| * the minimal text or, if PNG_RELEASE_BUILD is 0, the more verbose text |
| * including the 'condition' string. This value depends on whether the |
| * build supports an appropriate way of outputting the message. |
| * |
| * Note that PNG_AFFIRM_TEXT is not configurable but is worked out here: this |
| * is just the affirm code; there's no reason to allow configuration of this |
| * option. |
| */ |
| #if PNG_RELEASE_BUILD ?\ |
| (defined PNG_ERROR_TEXT_SUPPORTED) :\ |
| (defined PNG_WARNINGS_SUPPORTED) || (defined PNG_CONSOLE_IO_SUPPORTED) |
| # define PNG_AFFIRM_TEXT 1 |
| #else |
| # define PNG_AFFIRM_TEXT 0 |
| #endif /* PNG_AFFIRM_TEXT definition */ |
| |
| #define PNG_SRC_LINE (PNG_SRC_FILE + __LINE__) |
| |
| /* png_affirmpp and png_impossiblepp are macros to make the correct call to the |
| * png_affirm function; these macros do not assume that the png_structp is |
| * called png_ptr. |
| */ |
| #if PNG_RELEASE_BUILD |
| # define png_affirmpp(pp, cond)\ |
| do\ |
| if (!(cond)) png_affirm(pp, PNG_SRC_LINE);\ |
| while (0) |
| # define png_affirmexp(pp, cond)\ |
| ((cond) ? (void)0 : png_affirm(pp, PNG_SRC_LINE)) |
| # define png_handled(pp, m) ((void)0) |
| # define png_impossiblepp(pp, reason) png_affirm(pp, PNG_SRC_LINE) |
| |
| # define debug(cond) do {} while (0) |
| # define debug_handled(cond) do {} while (0) |
| # if PNG_LIBPNG_BUILD_BASE_TYPE >= PNG_LIBPNG_BUILD_RC |
| /* Make sure there are no 'UNTESTED' macros in released code: */ |
| # define UNTESTED libpng untested code |
| # endif |
| # define NOT_REACHED do {} while (0) |
| #else |
| # define png_affirmpp(pp, cond)\ |
| do\ |
| if (!(cond)) png_affirm(pp, #cond, PNG_SRC_LINE);\ |
| while (0) |
| # define png_affirmexp(pp, cond)\ |
| ((cond) ? (void)0 : png_affirm(pp, #cond, PNG_SRC_LINE)) |
| # define png_handled(pp, m) (png_handled_affirm((pp), (m), PNG_SRC_LINE)) |
| # define png_impossiblepp(pp, reason) png_affirm(pp, reason, PNG_SRC_LINE) |
| |
| # define debug(cond) png_affirmpp(png_ptr, cond) |
| # define debug_handled(cond)\ |
| do\ |
| if (!(cond)) png_handled(png_ptr, #cond);\ |
| while (0) |
| # define UNTESTED png_affirm(png_ptr, "untested code", PNG_SRC_LINE); |
| # define NOT_REACHED png_affirm(png_ptr, "NOT REACHED", PNG_SRC_LINE) |
| #endif |
| |
| #define affirm(cond) png_affirmpp(png_ptr, cond) |
| #define affirmexp(cond) png_affirmexp(png_ptr, cond) |
| #define handled(m) png_handled(png_ptr, (m)) |
| #define impossible(cond) png_impossiblepp(png_ptr, cond) |
| #define implies(a, b) debug(!(a) || (b)) |
| |
| /* The defines for PNG_SRC_FILE: */ |
| #define PNG_SRC_FILE_(f,lines) PNG_SRC_FILE_ ## f + lines |
| |
| #define PNG_SRC_FILE_png 0 |
| #define PNG_SRC_FILE_pngerror (PNG_SRC_FILE_png +8192) |
| #define PNG_SRC_FILE_pngget (PNG_SRC_FILE_pngerror +2048) |
| #define PNG_SRC_FILE_pngmem (PNG_SRC_FILE_pngget +2048) |
| #define PNG_SRC_FILE_pngpread (PNG_SRC_FILE_pngmem +1024) |
| #define PNG_SRC_FILE_pngread (PNG_SRC_FILE_pngpread +2048) |
| #define PNG_SRC_FILE_pngrio (PNG_SRC_FILE_pngread +8192) |
| #define PNG_SRC_FILE_pngrtran (PNG_SRC_FILE_pngrio +1024) |
| #define PNG_SRC_FILE_pngrutil (PNG_SRC_FILE_pngrtran +8192) |
| #define PNG_SRC_FILE_pngset (PNG_SRC_FILE_pngrutil +8192) |
| #define PNG_SRC_FILE_pngtrans (PNG_SRC_FILE_pngset +2048) |
| #define PNG_SRC_FILE_pngwio (PNG_SRC_FILE_pngtrans +4096) |
| #define PNG_SRC_FILE_pngwrite (PNG_SRC_FILE_pngwio +1024) |
| #define PNG_SRC_FILE_pngwtran (PNG_SRC_FILE_pngwrite +4096) |
| #define PNG_SRC_FILE_pngwutil (PNG_SRC_FILE_pngwtran +1024) |
| |
| #define PNG_SRC_FILE_arm_arm_init (PNG_SRC_FILE_pngwutil +8192) |
| #define PNG_SRC_FILE_arm_filter_neon_intrinsics\ |
| (PNG_SRC_FILE_arm_arm_init +1024) |
| |
| /* Add new files by changing the following line: */ |
| #define PNG_SRC_FILE_LAST (PNG_SRC_FILE_arm_filter_neon_intrinsics +1024) |
| |
| /* The following #define must list the files in exactly the same order as |
| * the above. |
| */ |
| #define PNG_FILES\ |
| PNG_apply(png)\ |
| PNG_apply(pngerror)\ |
| PNG_apply(pngget)\ |
| PNG_apply(pngmem)\ |
| PNG_apply(pngpread)\ |
| PNG_apply(pngread)\ |
| PNG_apply(pngrio)\ |
| PNG_apply(pngrtran)\ |
| PNG_apply(pngrutil)\ |
| PNG_apply(pngset)\ |
| PNG_apply(pngtrans)\ |
| PNG_apply(pngwio)\ |
| PNG_apply(pngwrite)\ |
| PNG_apply(pngwtran)\ |
| PNG_apply(pngwutil)\ |
| PNG_apply(arm_arm_init)\ |
| PNG_apply(arm_filter_neon_intrinsics)\ |
| PNG_end |
| |
| /* 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 |
| |
| /* This is a convenience for parameters which are not used in release |
| * builds. |
| */ |
| #define PNG_UNUSEDRC(param) only_rel(PNG_UNUSED(param)) |
| |
| /* Just a little check that someone hasn't tried to define something |
| * contradictory. |
| */ |
| #if (PNG_ZBUF_SIZE > 32768) && defined(PNG_MAX_MALLOC_64K) |
| # undef PNG_ZBUF_SIZE |
| # define PNG_ZBUF_SIZE 32768 |
| #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<type>(value) |
| # define png_upcast(type, value) static_cast<type>(value) |
| # define png_constcast(type, value) const_cast<type>(value) |
| # define png_aligncast(type, value) \ |
| static_cast<type>(static_cast<void*>(value)) |
| # define png_aligncastconst(type, value) \ |
| static_cast<type>(static_cast<const void*>(value)) |
| #else |
| # define png_voidcast(type, value) (value) |
| # define png_upcast(type, value) ((type)(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 |
| |
| /* 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 |
| |
| /* Buffer alignment control. These #defines control how the buffers used during |
| * read are aligned and how big they are. |
| */ |
| #ifndef PNG_ROW_BUFFER_ALIGN_TYPE |
| /* The absolute minimum alignment for a row buffer is that required for |
| * png_uint_32 direct access. The #define is of a legal C type that can be |
| * used as the type in the definition of the first member of a C union; give |
| * a typedef name if in doubt. |
| */ |
| # define PNG_ROW_BUFFER_ALIGN_TYPE png_uint_32 |
| #endif /* !ROW_BUFFER_ALIGN_TYPE */ |
| #ifndef PNG_ROW_BUFFER_BYTE_ALIGN |
| /* This is the minimum size in bytes of the buffer used while processing |
| * parts of row. Except at the end of the row pixels will always be |
| * processed in blocks such that the block size is a multiple of this number |
| */ |
| # define PNG_ROW_BUFFER_BYTE_ALIGN\ |
| ((unsigned int)/*SAFE*/(sizeof (PNG_ROW_BUFFER_ALIGN_TYPE))) |
| #endif /* !ROW_BUFFER_BYTE_ALIGN */ |
| #ifdef PNG_READ_USER_TRANSFORM_SUPPORTED |
| # define PNG_MAX_PIXEL_BYTES 16U /* 4x32-bit channels */ |
| #else /* !READ_USER_TRANSFORM */ |
| # define PNG_MAX_PIXEL_BYTES 8U /* 4x16-bit channels */ |
| #endif /* !READ_USER_TRANSFORM */ |
| /* PNG_ROW_BUFFER_SIZE is a compile time constant for the size of the row |
| * buffer. The minimum size of 2048 bytes is intended to allow the buffer to |
| * hold a complete 256 entry color map of 64-bit (8-byte) pixels. This is a |
| * requirement at some points of the colormap handling code. |
| * |
| * The maximum size is intended to allow (unsigned int) indexing of the buffer, |
| * it only affects systems with a 16-bit unsigned value where it limits the |
| * maximum to 4096 bytes. |
| */ |
| #define PNG_MIN_ROW_BUFFER_SIZE\ |
| (PNG_MAX_PIXEL_BYTES * PNG_ROW_BUFFER_BYTE_ALIGN * 8U) |
| #define PNG_MAX_ROW_BUFFER_SIZE ((UINT_MAX / 16U) + 1U) |
| #ifndef PNG_ROW_BUFFER_SIZE |
| # define PNG_ROW_BUFFER_SIZE\ |
| (PNG_MIN_ROW_BUFFER_SIZE < 2048U ? 2048U : PNG_MIN_ROW_BUFFER_SIZE) |
| #endif /* ROW_BUFFER_SIZE */ |
| |
| /* 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 as (int) in png.h) */ |
| /* #define PNG_HAVE_PLTE 0x02 (defined as (int) in png.h) */ |
| #define PNG_HAVE_IDAT 0x04U |
| /* #define PNG_AFTER_IDAT 0x08 (defined as (int) in png.h) */ |
| #define PNG_HAVE_IEND 0x10U |
| #define PNG_HAVE_PNG_SIGNATURE 0x20U |
| |
| #if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\ |
| defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) |
| /* See below for the definitions of the tables used in these macros */ |
| #define PNG_sRGB_FROM_LINEAR(pp, linear) png_check_byte(pp,\ |
| (png_sRGB_base[(linear)>>15] +\ |
| ((((linear)&0x7fffU)*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 /* PNG_SIMPLIFIED_READ/WRITE */ |
| |
| /* 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) + 32895U) >> 16) |
| #define PNG_DIV257(v16) PNG_DIV65535((png_uint_32)(v16) * 255U) |
| |
| /* Added to libpng-1.2.6 JB |
| * Modified in libpng-1.7.0 to avoid the intermediate calculation overflow |
| * when: |
| * |
| * pixel_bits == 4: any width over 0x3FFFFFFEU overflows |
| * pixel_bits == 2: any width over 0x7FFFFFFCU overflows |
| * |
| * In both these cases any width results in a rowbytes that fits in 32 bits. |
| * The problem arose in previous versions because the calculation used was |
| * simply ((width x pixel-bit-depth)+7)/8. At the cost of more calculations |
| * on pixel_depth this avoids the problem. |
| */ |
| #define PNG_SHIFTOF(pixel_bits/*<8*/) \ |
| ( (pixel_bits) == 1 ? 3 : \ |
| ( (pixel_bits) == 2 ? 2 : \ |
| ( (pixel_bits) == 4 ? 1 : \ |
| 0/*force bytes*/ ) ) ) |
| #define PNG_ADDOF(pixel_bits/*<8*/) ((1U<<PNG_SHIFTOF(pixel_bits))-1) |
| #define PNG_ROWBYTES(pixel_bits, width) \ |
| ((pixel_bits) >= 8 ? \ |
| ((png_alloc_size_t)(width) * ((pixel_bits) >> 3)) : \ |
| (((png_alloc_size_t)(width) + PNG_ADDOF(pixel_bits)) >> \ |
| PNG_SHIFTOF(pixel_bits)) ) |
| |
| /* This macros, added in 1.7.0, makes it easy to deduce the number of channels |
| * and therefore the pixel depth from the color type. The PNG specification |
| * numbers are used in preference to the png.h constants to make it more clear |
| * why the macro works. |
| */ |
| #define PNG_COLOR_TYPE_CHANNELS(ct)\ |
| (((ct) & PNG_COLOR_MASK_PALETTE) ?\ |
| 1U : 1U+((ct) & 2U/*COLOR*/)+(((ct)>>2)&1U/*ALPHA*/)) |
| #define PNG_CHANNELS(ps) PNG_COLOR_TYPE_CHANNELS((ps).color_type) |
| #define PNG_PIXEL_DEPTH(ps) (PNG_CHANNELS(ps) * (ps).bit_depth) |
| |
| /* 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) ) |
| |
| /* Handling of bit-field masks. Because the expression: |
| * |
| * bit_field & ~mask |
| * |
| * has implementation defined behavior in ANSI C-90 for many (int) values of |
| * 'mask' and because some of these are defined in png.h and passed in (int) |
| * parameters use of '~' has been expunged in libpng 1.7 and replaced by this |
| * macro, which is well defined in ANSI C-90 (there is a similar, 16-bit, |
| * version in pngstruct.h for the colorspace flags.) |
| */ |
| #define PNG_BIC_MASK(flags) (0xFFFFFFFFU - (flags)) |
| |
| /* 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 |
| |
| /* 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]); |
| #endif /* PNG_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. |
| */ |
| /* Affirm handling */ |
| PNG_INTERNAL_FUNCTION(void, png_affirm,(png_const_structrp png_ptr, |
| param_deb(png_const_charp condition) unsigned int position), PNG_NORETURN); |
| |
| #if !PNG_RELEASE_BUILD |
| PNG_INTERNAL_FUNCTION(void, png_handled_affirm,(png_const_structrp png_ptr, |
| png_const_charp message, unsigned int position), PNG_EMPTY); |
| /* This is not marked PNG_NORETURN because in PNG_RELEASE_BUILD it will |
| * disappear and control will pass through it. |
| */ |
| #endif /* !RELEASE_BUILD */ |
| |
| /* Character/byte range checking. */ |
| /* GCC complains about assignments of an (int) expression to a (char) even when |
| * it can readily determine that the value is in range. This makes arithmetic |
| * on (char) or (png_byte) values tedious. The warning is not issued by |
| * default, but libpng coding rules require no warnings leading to excessive, |
| * ridiculous and dangerous expressions of the form: |
| * |
| * <char> = (char)(expression & 0xff) |
| * |
| * They are dangerous because they hide the warning, which might actually be |
| * valid, and therefore merely enable introduction of undetected overflows when |
| * code is modified. |
| * |
| * The following macros exist to reliably detect any overflow in non-release |
| * builds. The theory here is that we really want to know about overflows, not |
| * merely hide a basically flawed compiler warning by throwing unnecessary casts |
| * into the code. The warnings disappear in RC builds so that the released |
| * (STABLE) version just assigns the value (with, possibly, a warning if someone |
| * turns on the -Wconversion GCC warning.) |
| * |
| * Doing it this way ensures that the code meets two very important aims: |
| * |
| * 1) Overflows are detected in pre-release tests; previously versions of libpng |
| * have been released that really did have overflows in the RGB calculations. |
| * 2) In release builds GCC specific operations, which may reduce the ability |
| * of other compilers and even GCC to optimize the code, are avoided. |
| * |
| * There is one important extra consequence for pre-release code; it is |
| * performing a lot of checks in pixel arithmetic that the release code won't |
| * perform. As a consequence a build time option, RANGE_CHECK, is provided |
| * to allow the checks to be turned off in pre-release when building for |
| * performance testing. This is a standard "_SUPPORTED" option except that it |
| * cannot be set in the system configuration (pnglibconf.h, pnglibconf.dfa). |
| * |
| * A separate macro PNG_BYTE() is provided to safely convert an unsigned value |
| * to the PNG byte range 0..255. This handles the fact that, technically, |
| * an ANSI-C (unsigned char), hence a (png_byte), may be able to store values |
| * outside this range. Note that if you are building on a system where this is |
| * true libpng is almost certainly going to produce errors; it has never been |
| * tested on such a system. For the moment pngconf.h ensures that this will |
| * not happen. |
| * |
| * PNG_UINT_16 does the same thing for a 16-bit value passed in an (int) or |
| * (png_uint_32) (where checking is not expected.) |
| */ |
| #if !PNG_RELEASE_BUILD |
| # ifndef PNG_NO_RANGE_CHECK /* Turn off even in pre-release */ |
| # define PNG_RANGE_CHECK_SUPPORTED |
| # endif |
| #endif |
| |
| #ifdef PNG_RANGE_CHECK_SUPPORTED |
| PNG_INTERNAL_FUNCTION(unsigned int, png_bit_affirm,(png_const_structrp png_ptr, |
| unsigned int position, unsigned int u, unsigned int bits), PNG_EMPTY); |
| |
| PNG_INTERNAL_FUNCTION(char, png_char_affirm,(png_const_structrp png_ptr, |
| unsigned int position, int c), PNG_EMPTY); |
| |
| PNG_INTERNAL_FUNCTION(png_byte, png_byte_affirm,(png_const_structrp png_ptr, |
| unsigned int position, int b), PNG_EMPTY); |
| |
| #if INT_MAX >= 65535 |
| PNG_INTERNAL_FUNCTION(png_uint_16, png_u16_affirm,(png_const_structrp png_ptr, |
| unsigned int position, int u), PNG_EMPTY); |
| # define png_check_u16(pp, u) (png_u16_affirm((pp), PNG_SRC_LINE, (u))) |
| #else |
| /* (int) cannot hold a (png_uint_16) so the above function just won't |
| * compile correctly, for the moment just do this: |
| */ |
| # define png_check_u16(pp, u) (u) |
| #endif |
| |
| # define png_check_bits(pp, u, bits)\ |
| (((1U<<(bits))-1) & png_bit_affirm((pp), PNG_SRC_LINE, (u), (bits))) |
| # define png_check_char(pp, c) (png_char_affirm((pp), PNG_SRC_LINE, (c))) |
| # define png_check_byte(pp, b) (png_byte_affirm((pp), PNG_SRC_LINE, (b))) |
| # define PNG_BYTE(b) ((png_byte)((b) & 0xFFU)) |
| # define PNG_UINT_16(u) ((png_uint_16)((u) & 0xFFFFU)) |
| #elif !(defined PNG_REMOVE_CASTS) /* && !RANGE_CHECK */ |
| # define png_check_bits(pp, u, bits) (((1U<<(bits))-1U) & (u)) |
| # define png_check_char(pp, c) ((char)(c)) |
| # define png_check_byte(pp, b) ((png_byte)(b)) |
| # define png_check_u16(pp, u) ((png_uint_16)(u)) |
| # define PNG_BYTE(b) ((png_byte)((b) & 0xFFU)) |
| # define PNG_UINT_16(u) ((png_uint_16)((u) & 0xFFFFU)) |
| #else /* !RANGE_CHECK */ |
| /* This is somewhat trust-me-it-works: if PNG_REMOVE_CASTS is defined then |
| * the casts, which might otherwise change the values, are completely |
| * removed. Use this to test your compiler to see if it makes *any* |
| * difference (code size or speed.) Currently NOT SUPPORTED. |
| * |
| * It also makes the PNG_BYTE and PNG_UINT_16 macros do nothing either |
| * NOTE: this seems safe at present but might lead to unexpected results |
| * if someone writes code to depend on the truncation. |
| */ |
| # define png_check_bits(pp, u, bits) (u) |
| # define png_check_char(pp, c) (c) |
| # define png_check_byte(pp, b) (b) |
| # define png_check_u16(pp, u) (u) |
| # define PNG_BYTE(b) (b) |
| # define PNG_UINT_16(u) (u) |
| #endif /* RANGE_CHECK */ |
| |
| /* Safe calculation of a rowbytes value; does a png_error if the system limits |
| * are exceeded. |
| */ |
| PNG_INTERNAL_FUNCTION(png_alloc_size_t,png_calc_rowbytes, |
| (png_const_structrp png_ptr, unsigned int pixel_depth, |
| png_uint_32 row_width),PNG_EMPTY); |
| |
| /* Common code to calculate the maximum number of pixels to transform or filter |
| * at one time; controlled by PNG_ROW_BUFFER_SIZE above: |
| */ |
| PNG_INTERNAL_FUNCTION(unsigned int,png_max_pixel_block, |
| (png_const_structrp png_ptr),PNG_EMPTY); |
| |
| /* Copy the row in row_buffer; this is the non-interlaced copy used in both the |
| * read and write code. 'x_in_dest' specifies whether the 'x' applies to |
| * the destination (sp->dp[x], x_in_dest tru) or the source (sp[x]->dp, |
| * x_in_dest false). |
| */ |
| PNG_INTERNAL_FUNCTION(void, png_copy_row,(png_const_structrp png_ptr, |
| png_bytep dp, png_const_bytep sp, png_uint_32 x/*in INPUT*/, |
| png_uint_32 width/*of INPUT*/, unsigned int pixel_depth, |
| int clear/*clear the final byte*/, int x_in_dest),PNG_EMPTY); |
| |
| /* Zlib support */ |
| #define PNG_UNEXPECTED_ZLIB_RETURN (-7) |
| PNG_INTERNAL_FUNCTION(void, png_zstream_error,(z_stream *zstream, int ret), |
| PNG_EMPTY); |
| /* Used by the zlib handling functions to ensure that z_stream::msg is always |
| * set before they return. |
| */ |
| |
| #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 |
| |
| /* 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_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); |
| |
| /* The next three functions are used by png_init_io to set the default |
| * implementations for reading or writing to a stdio (png_FILE_p) stream. |
| * They can't be static because in 1.7 png_init_io needs to reference them. |
| */ |
| #ifdef PNG_STDIO_SUPPORTED |
| # ifdef PNG_READ_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_read_data,(png_structp png_ptr, |
| png_bytep data, png_size_t length),PNG_EMPTY); |
| # endif /* READ */ |
| |
| # ifdef PNG_WRITE_SUPPORTED |
| 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 |
| PNG_INTERNAL_FUNCTION(void PNGCBAPI,png_default_flush,(png_structp png_ptr), |
| PNG_EMPTY); |
| # endif /* WRITE_FLUSH */ |
| # endif /* WRITE */ |
| #endif /* STDIO */ |
| |
| /* Reset the CRC variable. The CRC is initialized with the chunk tag (4 bytes). |
| * NOTE: at present png_struct::chunk_name MUST be set before this as well so |
| * that png_struct::current_crc is initialized correctly! |
| */ |
| PNG_INTERNAL_FUNCTION(void,png_reset_crc,(png_structrp png_ptr, |
| png_const_bytep chunk_tag), 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_voidp 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 data from whatever input you are using into the "data" buffer */ |
| PNG_INTERNAL_FUNCTION(void,png_read_data,(png_structrp png_ptr, png_voidp 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_voidp 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); |
| |
| /* 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_voidp ptr, png_size_t length),PNG_EMPTY); |
| |
| /* 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, unsigned int num_pal),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_voidp 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_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 |
| |
| #ifdef PNG_WRITE_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_write_start_IDAT,(png_structrp png_ptr), |
| PNG_EMPTY); |
| /* Do any required initialization before IDAT or row processing starts. */ |
| |
| /* Choose the best filter to use and filter the row data then write it out. If |
| * WRITE_FILTERING is not supported this just writes the data out with a zero |
| * (NONE) filter byte. |
| * |
| * This may be called multiple times per row, but calls must be in 'x' order; |
| * first a call with x 0 to mark the start of the row and, at the end, one with |
| * PNG_ROW_END set (this can be done in the same function call if the whole row |
| * is passed.) The following flags are used internally to control pass |
| * filtering and deflate: |
| */ |
| enum |
| { |
| png_pass_last =0x1U, /* This is the last pass in the image */ |
| png_pass_last_row =0x2U, /* This is the last row in a pass */ |
| png_pass_first_row =0x4U, /* This is the first row in a pass */ |
| png_row_end =0x8U, /* This is the last block in the row */ |
| png_no_row_info =0x0U /* Placeholder */ |
| |
| /* A useful macro; return true if this is the last block of the last row in |
| * the image. |
| */ |
| # define PNG_IDAT_END(f) (((f) & ~png_pass_first_row) == \ |
| (png_row_end+png_pass_last_row+png_pass_last)) |
| }; |
| PNG_INTERNAL_FUNCTION(void,png_write_png_data,(png_structrp png_ptr, |
| png_bytep prev_pixels, png_const_bytep unfiltered_row, png_uint_32 x, |
| unsigned int width/*pixels*/, unsigned int row_info_flags), |
| PNG_EMPTY); |
| |
| PNG_INTERNAL_FUNCTION(void,png_write_png_rows,(png_structrp png_ptr, |
| png_const_bytep *rows, png_uint_32 num_rows), PNG_EMPTY); |
| /* As above but rows[num_rows] of correctly (PNG) formated but unfiltered |
| * data are passed in. For an interlaced image the rows will be interlaced |
| * rows and therefore may be narrower than the image width. |
| * |
| * This function advances png_structp::pass and png_structp::row_number as |
| * required. |
| */ |
| |
| /* Release memory used by the deflate mechanism */ |
| PNG_INTERNAL_FUNCTION(void, png_deflate_destroy, (png_structp png_ptr), |
| PNG_EMPTY); |
| #endif /* WRITE */ |
| |
| #ifdef PNG_TRANSFORM_MECH_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_transform_free,(png_const_structrp png_ptr, |
| png_transformp *list),PNG_EMPTY); |
| /* Free the entire transform list, from the given point on. the argument is |
| * set to NULL. |
| */ |
| |
| PNG_INTERNAL_FUNCTION(void,png_init_transform_control,( |
| png_transform_controlp out, png_structp png_ptr),PNG_EMPTY); |
| /* Initialize a transform control for running the transform list forward (the |
| * read case, and write initialization, but the write case is called within |
| * pngtrans.c by the above function.) |
| */ |
| |
| #ifdef PNG_READ_TRANSFORMS_SUPPORTED |
| PNG_INTERNAL_FUNCTION(unsigned int,png_run_this_transform_list_forwards, |
| (png_transform_controlp tc, png_transformp *start, png_transformp end), |
| PNG_EMPTY); |
| /* Used by the transform cache code to run a sub-list, from *start to the |
| * transform end. |
| */ |
| #endif /* READ_TRANSFORMS */ |
| |
| #ifdef PNG_READ_SUPPORTED |
| PNG_INTERNAL_FUNCTION(unsigned int,png_run_transform_list_forwards, |
| (png_structp png_ptr, png_transform_controlp tc),PNG_EMPTY); |
| /* Run the transform list in the forwards direction (from PNG format to |
| * memory format). The transform control must be initialized completely by |
| * the caller. This function takes account of transforms which delete |
| * themselves during the run; it must be used. |
| */ |
| #endif /* READ */ |
| |
| #ifdef PNG_WRITE_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_run_transform_list_backwards, |
| (png_structp png_ptr, png_transform_controlp tc),PNG_EMPTY); |
| /* Run the transform list in the backwards direction (from memory format to |
| * PNG format). The transform control must be initialized completely by |
| * the caller. This function takes account of transforms which delete |
| * themselves during the run; it must be used. |
| */ |
| #endif /* WRITE */ |
| |
| PNG_INTERNAL_FUNCTION(png_transformp,png_add_transform,(png_structrp png_ptr, |
| size_t size, png_transform_fn fn, unsigned int order),PNG_EMPTY); |
| /* Add a transform, using the information in 'order' to control the position |
| * of the transform in the list, returning a pointer to the transform. The |
| * top 8 bits of 'order' control the position in the list. If a transform |
| * does not already exist in the list with the given value a new transform |
| * will be created and 'fn' and 'order' set. If there is a transform with |
| * that value 'fn' must match and 'order' will be updated by combining the |
| * new value in with a bitwise or (|). It is up to the function (fn) or the |
| * caller of png_add_transform to determine whether the combination is valid. |
| * |
| * 'size' is used when creating a new transform, it may be larger than |
| * (sizeof png_transform) if required to accomodate extra data. |
| * |
| * Prior to 1.7.0 transforms were executed in an order hard-wired into the |
| * code that executed the transform functions. This was summarized in the |
| * read case by the following comment from pngrtran.c |
| * (png_init_read_transformations), note that this has been marked up to |
| * indicate which PNG formats the transforms in the list apply to: |
| * |
| * *: applies to most formats |
| * A: only formats with alpha |
| * L: only low-bit-depth (less than 8 bits per component/pixel) |
| * H: only high-bit-depth (16-bits per component) |
| * |
| > From the code of png_do_read_transformations the order is: |
| * |
| * GGRR For example column: . no action |
| * AGG r acts on read |
| * BB w acts on write |
| * A B acts on both read and write |
| > |
| > r.r. 1) PNG_EXPAND (including PNG_EXPAND_tRNS) |
| > .r.r 2) PNG_STRIP_ALPHA (if no compose) |
| > ..rr 3) PNG_RGB_TO_GRAY |
| > rr.. 4) PNG_GRAY_TO_RGB iff !PNG_FLAG_BACKGROUND_IS_GRAY |
| > rrrr 5) PNG_COMPOSE |
| > rrrr 6) PNG_GAMMA |
| > .r.r 7) PNG_STRIP_ALPHA (if compose) |
| > .r.r 8) PNG_ENCODE_ALPHA |
| > rrrr 9) PNG_SCALE_16_TO_8 |
| > rrrr 10) PNG_16_TO_8 |
| > ..rr 11) PNG_QUANTIZE (converts to palette) |
| > rrrr 12) PNG_EXPAND_16 |
| > rr.. 13) PNG_GRAY_TO_RGB iff PNG_FLAG_BACKGROUND_IS_GRAY |
| > BB.. 14) PNG_INVERT_MONO |
| > .B.B 15) PNG_INVERT_ALPHA |
| > BBBB 16) PNG_SHIFT |
| * |
| * Note that transforms from this point on are used in 1.7.0 on palette |
| * indices as well; a png_set_pack request (for example) packs the palette |
| * index values if the output will be palettized and the grayscale values |
| * if it will not be (if the output is low-bit-grayscale, not palette.) |
| * |
| > B... 17) PNG_PACK |
| > ..BB 18) PNG_BGR |
| > B... 19) PNG_PACKSWAP |
| > rwrw 20) PNG_FILLER (includes PNG_ADD_ALPHA) |
| > .B.B 21) PNG_SWAP_ALPHA |
| > BBBB 22) PNG_SWAP_BYTES |
| > BBBB 23) PNG_USER_TRANSFORM [must be last] |
| * |
| * Finally, outside the set of transforms prior to 1.7.0, the libpng |
| * interlace handling required the pixels to be replicated to match the pixel |
| * spacing in the image row; the first part the pre-1.7.0 interlace support, |
| * this is still the case when reading, but for writing the interlace is now |
| * a transform: |
| * |
| > BBBB 24) png_do_{read,write}_interlace (interlaced images only). |
| * |
| * First transforms are grouped according to basic function using the top 3 |
| * bits of the order code: |
| */ |
| # define PNG_TR_START 0x0000U /* initial ops on the PNG data */ |
| # define PNG_TR_ARITHMETIC 0x2000U /* arithmetic linear operations */ |
| # define PNG_TR_CHANNEL 0x4000U /* PNG conformant format changes */ |
| # define PNG_TR_QUANTIZE 0x6000U /* quantize and following operations */ |
| # define PNG_TR_ENCODING 0x8000U /* Row encoding transforms */ |
| # define PNG_TR_INTERLACE 0xA000U /* write interlace transform */ |
| /* |
| * In libpng 1.7.0 the check on palette index values is moved to the start |
| * (of read, end of write, which is where it was before) immediately after |
| * the MNG filter handling |
| */ |
| # define PNG_TR_MNG_INTRAPIXEL (PNG_TR_START + 0x0100U) |
| /* Perform intra-pixel differencing (write) or un-differencing on read. */ |
| # define PNG_TR_CHECK_PALETTE (PNG_TR_START + 0x0200U) |
| /* Done before at the start on read, at the end on write to give a |
| * consistent postion: |
| * |
| * PNG_RWTR_CHECK_PALETTE PI W11: happens in pngwrite.c last |
| */ |
| # define PNG_TR_START_CACHE (PNG_TR_START + 0x0300U) |
| /* Not used on a transform; this is just a marker for the point at which |
| * palette or low-bit-depth caching can start on read. (The previous |
| * operations cannot be cached). |
| */ |
| # define PNG_TR_INIT_ALPHA (PNG_TR_START + 0x0400U) |
| /* This just handles alpha/tRNS initialization issues to resolve the |
| * inter-dependencies with tRNS expansion and background composition; it |
| * doesn't do anything itself, just sets flags and pushes transforms. |
| */ |
| /* |
| * Prior to 1.7 the arithmetic operations interleaved with the RGB-to-gray |
| * and alpha strip byte level ops. This was done to reduce the amount of |
| * data processed, i.e. it was an optimization not a requirement. These |
| * operations were preceded by the 'expand' operations, which is the |
| * opposite; it was done to simplify the code and actually slows things down |
| * in the low bit depth gray case. The full list of operations after expand, |
| * in the 1.6 order, is: |
| * |
| * PNG_TR_STRIP_ALPHA png_do_strip_channel (sometimes) |
| * PNG_TR_RGB_TO_GRAY png_do_rgb_to_gray |
| * PNG_TR_GRAY_TO_RGB png_do_gray_to_rgb (sometimes) |
| * PNG_TR_COMPOSE png_do_compose |
| * PNG_TR_GAMMA png_do_gamma (if no RGB_TO_GRAY) |
| * PNG_TR_STRIP_ALPHA png_do_strip_channel (other times) |
| * PNG_TR_ENCODE_ALPHA png_do_encode_alpha |
| * |
| * In 1.7 the operations are moved round somewhat, including moving alpha and |
| * 16-to-8 bit reduction later. This leaves the following operations: |
| * |
| * PNG_TR_RGB_TO_GRAY png_do_rgb_to_gray |
| * PNG_TR_COMPOSE png_do_compose |
| * PNG_TR_GAMMA png_do_gamma (if no RGB_TO_GRAY) |
| * PNG_TR_ENCODE_ALPHA png_do_encode_alpha |
| * |
| * Prior to 1.7 some combinations of transforms would do gamma correction |
| * twice, the actual implementation in 1.7 is to use the following order and |
| * rely on the cache code to optimize gray 1,2,4,8 and (of course) palette. |
| */ |
| # define PNG_TR_COMPOSE (PNG_TR_ARITHMETIC + 0x0100U) |
| /* Handle background composition. This may need to push a gray-to-rgb |
| * transform if the background is RGB for gray input. This precedes RGB |
| * to gray convertion so that it can handle tRNS appropriately when the |
| * background is in the PNG encoding however, typically, the processing |
| * happens at PNG_TR_COMPOSE_ALPHA below. |
| * |
| * NOTE: this must be the first arithmetic transform because the code in |
| * png_init_background relies on png_transform_control::gamma being the |
| * original PNG gamma. |
| */ |
| # define PNG_TR_RGB_TO_GRAY (PNG_TR_ARITHMETIC + 0x0200U) /* to gray */ |
| /* Convert any RGB input (8/16 bit depth, RGB, RGBA) to linear gray |
| * 16-bit. This happens first because it cannot be cached; the input data |
| * has 24 or 48 bits of uncorrelated data so the transform has to happen |
| * pixel-by-pixel. Internally the transform may maintain an 8 or 16-bit |
| * gamma correction table (to 16-bit linear) to speed things up. |
| * |
| * NOTE: this transform must follow PNG_TR_COMPOSE with no intervening |
| * transforms; see the code in png_init_background (pngrtran.c) which |
| * relies on this during PNG_TC_INIT_FORMAT. |
| */ |
| # define PNG_TR_COMPOSE_ALPHA (PNG_TR_ARITHMETIC + 0x0300U) |
| /* Compose alpha composition and tRNS handling when the background is a |
| * screen color. Pushed by PNG_TR_COMPOSE as required. |
| */ |
| # define PNG_TR_GAMMA_ENCODE (PNG_TR_ARITHMETIC + 0x1F00U) /* last */ |
| /* Gamma encode the input. This encodes the gray or RGB channels to the |
| * required bit depth and either scales the alpha channel or encodes it as |
| * well, depending on the requested alpha encoding. |
| */ |
| /* |
| * The 'expand' operations come after the arithmetic ones in libpng 1.7, this |
| * forces the arithmetic stuff to do the expand, but since arithmetic is (in |
| * 1.7) normally done in 16-bit linear this avoids spurious expands. |
| */ |
| # define PNG_TR_EXPAND (PNG_TR_CHANNEL + 0x0100U) |
| /* Includes: |
| * |
| * PNG_TR_EXPAND_PALETTE palette images only, includes tRNS |
| * PNG_TR_EXPAND_LBP_GRAY grayscale low-bit depth only |
| * PNG_TR_EXPAND_tRNS non-palette images only |
| */ |
| # define PNG_TR_SCALE_16_TO_8 (PNG_TR_CHANNEL + 0x0200U) |
| /* Comes after the expand and before the chop version; note that it works on |
| * the pixel values directly, so it is a linear transform on a non-linear |
| * value. |
| */ |
| /* |
| * To handle transforms that affect the palette entries, not the palette |
| * indices in the row data, libpng 1.7 reorders some of the post-quantize |
| * transformations to put all the "PC" transforms ahead of all the "PI" |
| * transforms. The "PC" transforms that came after png_do_quantize in libpng |
| * 1.6 cannot be ordered to be before so they are included in the |
| * PNG_TR_QUANTIZE section. The PI transforms are all in PNG_TR_ENCODING, |
| * PNG_GRAY_TO_RGB is moved before PNG_TR_QUANTIZE to avoid the unpredictable |
| * behavior of png_set_quantize that otherwise arises. |
| * |
| * The transforms in the PNG_TR_QUANTIZE section are: |
| * |
| * PNG_TR_EXPAND_16 !P !W |
| * PNG_RWTR_INVERT_MONO !P W10: invert the gray channel |
| * PNG_RWTR_INVERT_ALPHA PC W8: invert the alpha channel |
| * PNG_RWTR_SHIFT PC W6: read: down, write: scale up |
| * PNG_RWTR_BGR !P W9 |
| * PNG_RWTR_FILLER !P W2: add on R, remove on W |
| * PNG_RWTR_SWAP_ALPHA !P W7 |
| * PNG_RWTR_SWAP_16 !P W5 |
| * |
| * The ones in PNG_TR_ENCODING are: |
| * |
| * PNG_RWTR_PACK PI W4: R: unpack bytes, W: pack |
| * PNG_RWTR_PIXEL_SWAP PI W3: Swap pixels in a byte |
| * PNG_RWTR_USER PI W1 |
| */ |
| |
| # define PNG_TR_CHANNEL_PREQ (PNG_TR_CHANNEL + 0x1F00U) |
| /* The channel swap transforms that must happen before PNG_TR_QUANTIZE: |
| * |
| * PNG_TR_STRIP_ALPHA |
| * PNG_TR_CHOP_16_TO_8 |
| * PNG_TR_GRAY_TO_RGB |
| */ |
| # define PNG_TR_CHANNEL_POSTQ (PNG_TR_QUANTIZE + 0x0100U) |
| /* The post-quantize channel swap transforms: |
| * |
| * PNG_TR_EXPAND_16 !P !W |
| * PNG_RWTR_BGR !P W9 |
| * PNG_RWTR_FILLER !P W2: (filler) add on R, remove on W |
| * PNG_RWTR_SWAP_ALPHA !P W7 |
| * PNG_RWTR_SWAP_16 !P W5 |
| * |
| * The 'CHANNEL' operation sets the transform_control channel_add flag for |
| * use below. |
| */ |
| # define PNG_TR_INVERT (PNG_TR_QUANTIZE + 0x0200U) |
| /* Invert MONO and ALPHA. If the channel_add flag is set in the transform |
| * control INVERT_ALPHA will not be done; the png_add_alpha/filler APIs |
| * happened after png_set_invert_alpha in earlier versions so the filler |
| * value had to include the invert. |
| * |
| * PNG_RWTR_INVERT_MONO !P W10: invert the gray channel |
| * PNG_RWTR_INVERT_ALPHA PC W8: invert the alpha channel |
| */ |
| # define PNG_TR_SHIFT (PNG_TR_QUANTIZE + 0x0300U) |
| /* The channel shift, except that if the channel_add flag has been set the |
| * alpha channel is not shifted. |
| * |
| * PNG_RWTR_SHIFT PC W6: read: down, write: scale up |
| */ |
| # define PNG_TR_PACK (PNG_TR_ENCODING + 0x0200U) |
| /* PNG_RWTR_PACK PI W4: R: unpack bytes, W: pack */ |
| # define PNG_TR_PIXEL_SWAP (PNG_TR_ENCODING + 0x0300U) |
| /* PNG_RWTR_PIXEL_SWAP PI W3: Swap pixels in a byte */ |
| # define PNG_TR_USER (PNG_TR_ENCODING + 0x1F00U) |
| /* The user transform; must be last before the interlace handling because it |
| * does unpredictable things to the format. |
| * |
| * PNG_RWTR_USER PI W1 |
| */ |
| |
| PNG_INTERNAL_FUNCTION(png_transformp,png_push_transform,(png_structrp png_ptr, |
| size_t size, png_transform_fn fn, png_transformp *transform, |
| png_transform_controlp tc),PNG_EMPTY); |
| /* As png_add_transform except that the new transform is inserted ahead of |
| * the given transform (*transform). The new transform is returned, but it |
| * will also invariably be in *transform. If 'tc' is not NULL the transform |
| * callback will also be called; it needs to be called if this function is |
| * called while transforms are being run. |
| * |
| * 'fn' must not be NULL. |
| * |
| * The transform is inserted with the same 'order' as the passed in |
| * *transform, that transform and following transforms are moved up ('order' |
| * is incremented) as required to make space. Consequently, unlike with |
| * png_add_transform, the transform will always be new. To detect loops |
| * (*transform)->fn must not be the same as the passed in 'fn'. |
| */ |
| |
| PNG_INTERNAL_FUNCTION(png_voidp,png_transform_cast_check, |
| (png_const_structp png_ptr, unsigned int src_line, png_transformp tr, |
| size_t size),PNG_EMPTY); |
| /* Given a pointer to a transform, 'tr' validate that the underlying derived |
| * class has size 'size' using the tr->size field and return the same |
| * pointer. If there is a size mismatch the function does an affirm using |
| * the given line number. |
| */ |
| #define png_transform_cast(type, pointer) png_voidcast(type*,\ |
| png_transform_cast_check(png_ptr, PNG_SRC_LINE, (pointer), sizeof (type))) |
| /* This takes a pointer to a transform and safely returns a pointer to a |
| * derived transform class (type); type must not have the pointer. It |
| * validates the 'size' field. Derived classes start with a png_transform |
| * as the first member called 'tr'. |
| */ |
| #endif /* TRANSFORM_MECH_SUPPORTED */ |
| |
| #ifdef PNG_READ_TRANSFORMS_SUPPORTED |
| /* Remove a transform from a list, moving the next transform down into |
| * *transform. |
| */ |
| PNG_INTERNAL_FUNCTION(void,png_remove_transform,(png_const_structp png_ptr, |
| png_transformp *transform),PNG_EMPTY); |
| |
| /* Initializer for read transforms that handles caching, palette update and |
| * palette expansion. |
| */ |
| PNG_INTERNAL_FUNCTION(unsigned int,png_read_init_transform_mech, |
| (png_structp png_ptr, png_transform_control *tc),PNG_EMPTY); |
| |
| /* 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 |
| |
| /* APIs which do a tranform on both read and write but where the implementation |
| * is separate for each; the read and write init functions are in pngrtran.c or |
| * pngwtran.c, the API is in pngtrans.c |
| */ |
| #if defined(PNG_READ_PACK_SUPPORTED) || defined(PNG_READ_EXPAND_SUPPORTED) |
| PNG_INTERNAL_FUNCTION(void,png_init_read_pack,(png_transformp *transform, |
| png_transform_controlp tc),PNG_EMPTY); |
| #endif /* READ_PACK || READ_EXPAND */ |
| #ifdef PNG_WRITE_PACK_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_init_write_pack,(png_transformp *transform, |
| png_transform_controlp tc),PNG_EMPTY); |
| #endif /* WRITE_PACK */ |
| |
| /* 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_transform_controlp row_info, png_bytep row, int at_start),PNG_EMPTY); |
| #endif /* FILLER */ |
| |
| #if defined(PNG_READ_INVERT_SUPPORTED) || defined(PNG_WRITE_INVERT_SUPPORTED) |
| PNG_INTERNAL_FUNCTION(void,png_do_invert,(png_transform_controlp row_info, |
| png_bytep row),PNG_EMPTY); |
| #endif /* INVERT */ |
| |
| #if defined(PNG_READ_INVERT_ALPHA_SUPPORTED) ||\ |
| defined(PNG_WRITE_INVERT_ALPHA_SUPPORTED) |
| PNG_INTERNAL_FUNCTION(void,png_do_invert_alpha,(png_transform_controlp row_info, |
| png_bytep row),PNG_EMPTY); |
| #endif /* INVERT_ALPHA */ |
| |
| #ifdef PNG_READ_RGB_TO_GRAY_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_add_rgb_to_gray_byte_ops,(png_structrp png_ptr, |
| png_transform_controlp tc, unsigned int index, unsigned int order), |
| PNG_EMPTY); |
| /* This is an init-time utility to add appropriate byte ops to select a given |
| * channel from R/G/B. |
| */ |
| #endif /* READ_RGB_TO_GRAY */ |
| |
| #if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED) &&\ |
| defined(PNG_READ_BACKGROUND_SUPPORTED) |
| PNG_INTERNAL_FUNCTION(void,png_push_gray_to_rgb_byte_ops,(png_transformp *tr, |
| png_transform_controlp tc), PNG_EMPTY); |
| /* This is an init-time utility to push appropriate byte ops to expand a |
| * grayscale PNG data set to RGB. It calls the function callback so 'tc' |
| * must be non-NULL. |
| */ |
| #endif /* GRAY_TO_RGB && READ_BACKGROUND */ |
| |
| #ifdef PNG_READ_STRIP_ALPHA_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_add_strip_alpha_byte_ops,(png_structrp png_ptr), |
| PNG_EMPTY); |
| /* Called from pngrtran.c to add the relevant byte op. */ |
| #endif /* READ_STRIP_ALPHA */ |
| |
| /* The following decodes the appropriate chunks, and does error correction, |
| * then calls the appropriate callback for the chunk if it is valid. |
| */ |
| |
| #ifdef PNG_READ_SUPPORTED |
| PNG_INTERNAL_FUNCTION(png_bytep,png_read_buffer,(png_structrp png_ptr, |
| png_alloc_size_t new_size, int warn),PNG_EMPTY); |
| /* Manage the dynamically allocated read buffer */ |
| |
| /* Shared READ IDAT handling: */ |
| PNG_INTERNAL_FUNCTION(void,png_read_start_IDAT,(png_structrp png_ptr), |
| PNG_EMPTY); |
| /* Initialize the row buffers, etc. */ |
| |
| typedef enum |
| { |
| png_row_incomplete, |
| /* more IDAT data needed for row */ |
| png_row_process, |
| /* png_struct::row_buffer contains a complete row */ |
| png_row_repeat, |
| /* row not in this pass, but the existing row may be used */ |
| png_row_skip |
| /* row not in pass and no appropriate data; skip this row */ |
| } png_row_op; |
| PNG_INTERNAL_FUNCTION(png_row_op,png_read_process_IDAT,(png_structrp png_ptr, |
| png_bytep transformed_row, png_bytep display_row, int save_row), |
| PNG_EMPTY); |
| /* Process a block of IDAT data; the routine returns early if it has |
| * obtained a row. It is valid to call this routine with no input data; |
| * it will return png_row_incomplete if it needs input. |
| * |
| * transformed_row: The transformed pixels of the input are written here. |
| * For interlaced images only the pixels in the pass will |
| * be written, the other pixels will not be touched. |
| * |
| * display_row: The transformed pixels but replicated to that the entire |
| * buffer will have been initialized. For passes after the |
| * first the pixels written are determined by the 'block' |
| * algorithm; only those *following* pixels which are |
| * written by *later* passes are written (with a copy of the |
| * pixel from the pass.) |
| * |
| * save_row: A boolean which indicates that the row (unexpanded) |
| * should be saved in png_struct::transformed_row. This can |
| * be used in a later call to png_combine_row. |
| * |
| * During reading the row is built up until png_row_process is returned. At |
| * this point png_struct::row_buffer contains the original PNG row from the |
| * file and, if save_row was set, png_struct::transformed_row contains the |
| * row after the selected row transforms have been performed. For interlaced |
| * images both are the width of the interlace pass. |
| * |
| * When png_row_repeat is returned the same is true, except that the buffers |
| * still contain the contents of the preceding row (the one where this |
| * funciton returned png_row_pricess). |
| * |
| * The row buffers should not be accessed if png_row_skip is returned; this |
| * row is not modified in the current pass. |
| */ |
| |
| PNG_INTERNAL_FUNCTION(void,png_read_free_row_buffers,(png_structrp png_ptr), |
| PNG_EMPTY); |
| /* Free allocated row buffers; done as soon as possible to avoid carrying |
| * around all the memory for longer than necessary. |
| */ |
| |
| PNG_INTERNAL_FUNCTION(int,png_read_finish_IDAT,(png_structrp png_ptr), |
| PNG_EMPTY); |
| /* Complete reading of the IDAT chunks. This returns 0 if more data is to |
| * be read, 1 if the zlib stream has terminated. Call this routine with |
| * zstream.avail_in greater than zero unless there is no more input data. |
| * When zstream_avail_in is 0 on entry and the stream does not terminate |
| * an "IDAT truncated" error will be output. |
| * |
| * ENTRY: png_ptr->zstream.{next,avail}_in points to more IDAT data, if |
| * available, otherwise avail_in should be 0. |
| * RET 0: the LZ stream is still active, more IDAT date is required, if |
| * available, the routine *must* be called again. |
| * RET 1: the LZ stream has been closed and an error may have been output; |
| * png_ptr->zstream_error says whether it has. If not and there |
| * is more IDAT data available the caller should output an |
| * appropriate (too much IDAT) error message. |
| */ |
| |
| #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_cache_known_unknown,(png_structrp png_ptr, |
| png_const_bytep add, int keep),PNG_EMPTY); |
| /* Update the png_struct::known_unknown bit cache which stores whether each |
| * known chunk should be treated as unknown. |
| */ |
| #endif |
| |
| typedef enum |
| { |
| png_chunk_skip = 0, /* Skip this chunk */ |
| png_chunk_unknown, /* Pass the chunk to png_handle_unknown */ |
| png_chunk_process_all, /* Process the chunk all at once */ |
| png_chunk_process_part /* Process the chunk in parts (for IDAT) */ |
| } png_chunk_op; |
| |
| PNG_INTERNAL_FUNCTION(png_chunk_op,png_find_chunk_op,(png_structrp png_ptr), |
| PNG_EMPTY); |
| /* Given a chunk in png_struct::{chunk_name,chunk_length} validate the name |
| * and work out how it should be handled. This function checks the chunk |
| * location using png_struct::mode and will set the mode appropriately for |
| * the known critical chunks but otherwise makes no changes to the stream |
| * read state. |
| */ |
| |
| PNG_INTERNAL_FUNCTION(void,png_check_chunk_name,(png_const_structrp png_ptr, |
| const png_uint_32 chunk_name),PNG_EMPTY); |
| |
| PNG_INTERNAL_FUNCTION(void,png_check_chunk_length,(png_const_structrp png_ptr, |
| const png_uint_32 chunk_length),PNG_EMPTY); |
| |
| #ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED |
| PNG_INTERNAL_FUNCTION(void,png_handle_unknown,(png_structrp png_ptr, |
| png_inforp info_ptr, png_bytep chunk_data),PNG_EMPTY); |
| /* Handle an unknown chunk that needs to be processed. It is only valid |
| * to call this after png_find_chunk_op returns png_chunk_unknown. The |
| * data argument points to the png_struct::chunk_length bytes of the chunk |
| * data. |
| */ |
| #endif /* READ_UNKNOWN_CHUNKS */ |
| |
| PNG_INTERNAL_FUNCTION(void,png_handle_chunk,(png_structrp png_ptr, |
| png_inforp info_ptr),PNG_EMPTY); |
| /* The chunk to handle is in png_struct::chunk_name,chunk_length. |
| * |
| * NOTE: at present it is only valid to call this after png_find_chunk_op |
| * has returned png_chunk_process_all and all the data is available for |
| * png_handle_chunk (via the libpng read callback.) |
| */ |
| #endif /* READ */ |
| |
| PNG_INTERNAL_FUNCTION(void,png_init_row_info,(png_structrp png_ptr),PNG_EMPTY); |
| /* Set the png_struct::row_ members from the PNG file information, running |
| * transforms if required. |
| */ |
| |
| /* 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 is_color), |
| 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 is_color), |
| 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 /* sRGB */ |
| #endif /* iCCP */ |
| #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); |
| |
| #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. |
| * |
| * With PNG_CHUNK_FATAL an error can be marked as unrecoverable, and the |
| * function will not return. |
| * |
| * 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 */ |
| #define PNG_CHUNK_FATAL 3 /* an unrecoverable error */ |
| |
| #ifndef PNG_ERROR_TEXT_SUPPORTED |
| # define png_chunk_report(pp,e,v) png_chunk_report(pp,NULL,v) |
| #endif |
| |
| /* 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 /* GAMMA || INCH_CONVERSIONS || READ_pHYs */ |
| |
| #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. |
| */ |
| PNG_INTERNAL_FUNCTION(unsigned int,png_gamma_nxmbit_correct, |
| (unsigned int value, png_fixed_point gamma_val, unsigned int n/*input bits*/, |
| unsigned int m/*output bits */),PNG_EMPTY); |
| /* In this case the value must have 'n' bits and the output will have 'm' |
| * bits. |
| */ |
| |
| #if !PNG_RELEASE_BUILD |
| PNG_INTERNAL_FUNCTION(int,png_gamma_check,(png_const_structrp png_ptr, |
| png_const_transform_controlp tc),PNG_EMPTY); |
| /* Debugging only routine to repeat the test used above to determine if the |
| * gamma was insignificant. |
| */ |
| #endif /* !RELEASE_BUILD */ |
| #endif /* READ_GAMMA */ |
| |
| #ifdef PNG_SIMPLIFIED_READ_SUPPORTED |
| /* Internal check function to saw if the gamma of the PNG data is far enough |
| * from the given screen gamma to require gamma correction (only needed for a |
| * bug work-round in the simplified API). |
| * TODO: it should be possible to remove the bug work-round in 1.7 |
| */ |
| PNG_INTERNAL_FUNCTION(int,png_need_gamma_correction,(png_const_structrp png_ptr, |
| png_fixed_point gamma, int sRGB_output),PNG_EMPTY); |
| #endif /* SIMPLIFIED_READ */ |
| |
| /* This is a utility macro to say whether a gamma value is close enough to sRGB. |
| * The test is now hardwired: |
| * |
| * API CHANGE: prior to 1.7 this would depend on the build-time |
| * PNG_GAMMA_THRESHOLD_FIXED setting, which would cause inconsistent results |
| * when the setting was changed. Since this setting can now be changed at |
| * run-time it seems more sensible to have a single fixed definition of 'sRGB'. |
| * |
| * The test is approximately +/- 1%, it allows any decimal value from 0.45 (the |
| * two digit rounded version of 1/2.2) to just under 0.46). |
| */ |
| #define PNG_GAMMA_IS_sRGB(g) ((g) >= 45000 && (g) < 46000) |
| |
| /* 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); |
| |
| /* Safely initialize a stdio pointer - used by both the read and the write |
| * code. |
| */ |
| #ifdef PNG_STDIO_SUPPORTED |
| PNG_INTERNAL_FUNCTION(int,png_image_init_io,(png_imagep image, png_FILE_p file), |
| PNG_EMPTY); |
| #endif /* STDIO */ |
| |
| #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 */ |
| |
| #ifdef PNG_READ_SUPPORTED |
| PNG_INTERNAL_FUNCTION(png_int_32, png_read_setting, (png_structrp png_ptr, |
| png_uint_32 setting, png_uint_32 parameter, png_int_32 value), PNG_EMPTY); |
| #endif /* READ */ |
| #ifdef PNG_WRITE_SUPPORTED |
| PNG_INTERNAL_FUNCTION(png_int_32, png_write_setting, (png_structrp png_ptr, |
| png_uint_32 setting, png_uint_32 parameter, png_int_32 value), PNG_EMPTY); |
| /* Implementations of read and write settings, in pngrutil.c and pngwutil.c |
| * respectively. |
| */ |
| #endif /* WRITE */ |
| |
| /* Maintainer: Put new private prototypes here ^ */ |
| |
| /* 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_structrp 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 |
| |
| #include "pngdebug.h" |
| |
| /* EXTENSION SPECIFIC FUNCTIONS */ |
| #ifdef PNG_EXTENSION_HEADER |
| # include PNG_EXTENSION_HEADER |
| #endif /* EXTENSION_HEADER */ |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* PNG_VERSION_INFO_ONLY */ |
| #endif /* PNGPRIV_H */ |
