* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
* (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
*
- * Last changed in libpng 1.5.2 [March 31, 2011]
+ * Last changed in libpng 1.5.7 [December 15, 2011]
*
* This code is released under the libpng license.
* For conditions of distribution and use, see the disclaimer
#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 */
+
/* This is required for the definition of abort(), used as a last ditch
* error handler when all else fails.
*/
#include <stdlib.h>
-#define PNGLIB_BUILD
+/* This is used to find 'offsetof', used below for alignment tests. */
+#include <stddef.h>
+
+#define PNGLIB_BUILD /*libpng is being built, not used*/
+
#ifdef PNG_USER_CONFIG
# include "pngusr.h"
/* These should have been defined in pngusr.h */
# define PNG_USER_DLLFNAME_POSTFIX "Cb"
# endif
#endif
+
+/* 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
+
#include "png.h"
#include "pnginfo.h"
#include "pngstruct.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 used for 16 bit gamma tables - only the top level pointers are const,
* this could be changed:
*/
# define PNG_ZBUF_SIZE 65536L
#endif
-/* If warnings or errors are turned off the code is disabled
- * or redirected here.
+/* PNG_STATIC is used to mark internal file scope functions if they need to be
+ * accessed for implementation tests (see the code in tests/?*).
*/
-#ifndef PNG_WARNINGS_SUPPORTED
-# define png_warning(s1,s2) ((void)0)
-# define png_chunk_warning(s1,s2) ((void)0)
+#ifndef PNG_STATIC
+# define PNG_STATIC static
+#endif
+
+/* C99 restrict is used where possible, to do this 'restrict' is defined as
+ * empty if we can't be sure it is supported. configure builds have already
+ * done this work.
+ */
+#ifdef PNG_CONFIGURE_LIBPNG
+# define PNG_RESTRICT restrict
+#else
+ /* Modern compilers support restrict, but assume not for anything not
+ * recognized here:
+ */
+# if defined __GNUC__ || defined _MSC_VER || defined __WATCOMC__
+# define PNG_RESTRICT restrict
+# else
+# define PNG_RESTRICT
+# endif
+#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(s1,s2) ((void)(s1))
+# define png_chunk_warning(s1,s2) ((void)(s1))
+# 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_error(s1,s2) png_err(s1)
# 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)
+#else
+# define png_voidcast(type, value) (value)
+#endif /* __cplusplus */
+
#ifndef PNG_EXTERN
/* The functions exported by PNG_EXTERN are internal functions, which
* aren't usually used outside the library (as far as I know), so it is
* debatable if they should be exported at all. In the future, when it
* is possible to have run-time registry of chunk-handling functions,
* some of these might be made available again.
-# define PNG_EXTERN extern
+ *
+ * 1.5.7: turned the use of 'extern' back on, since it is localized to pngpriv.h
+ * it should be safe now (it is unclear why it was turned off.)
*/
-# define PNG_EXTERN
+# define PNG_EXTERN extern
#endif
/* Some fixed point APIs are still required even if not exported because
# define NOCHECK 0
# define CVT_PTR(ptr) (png_far_to_near(png_ptr,ptr,CHECK))
# define CVT_PTR_NOCHECK(ptr) (png_far_to_near(png_ptr,ptr,NOCHECK))
-# define png_strcpy _fstrcpy
-# define png_strncpy _fstrncpy /* Added to v 1.2.6 */
# define png_strlen _fstrlen
# define png_memcmp _fmemcmp /* SJT: added */
# define png_memcpy _fmemcpy
# define png_memset _fmemset
-# define png_sprintf sprintf
#else
# ifdef _WINDOWS_ /* Favor Windows over C runtime fns */
# define CVT_PTR(ptr) (ptr)
# define CVT_PTR_NOCHECK(ptr) (ptr)
-# define png_strcpy lstrcpyA
-# define png_strncpy lstrcpynA
# define png_strlen lstrlenA
# define png_memcmp memcmp
# define png_memcpy CopyMemory
# define png_memset memset
-# define png_sprintf wsprintfA
# else
# define CVT_PTR(ptr) (ptr)
# define CVT_PTR_NOCHECK(ptr) (ptr)
-# define png_strcpy strcpy
-# define png_strncpy strncpy /* Added to v 1.2.6 */
# define png_strlen strlen
# define png_memcmp memcmp /* SJT: added */
# define png_memcpy memcpy
# define png_memset memset
-# define png_sprintf sprintf
# endif
#endif
-/* End of memory model/platform independent support */
-#ifndef PNG_NO_SNPRINTF
-# ifdef _MSC_VER
-# define png_snprintf _snprintf /* Added to v 1.2.19 */
-# define png_snprintf2 _snprintf
-# define png_snprintf6 _snprintf
+/* 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_TO_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
-# define png_snprintf snprintf /* Added to v 1.2.19 */
-# define png_snprintf2 snprintf
-# define png_snprintf6 snprintf
+# 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
- /* You don't have or don't want to use snprintf(). Caution: Using
- * sprintf instead of snprintf exposes your application to accidental
- * or malevolent buffer overflows. If you don't have snprintf()
- * as a general rule you should provide one (you can get one from
- * Portable OpenSSH).
- */
-# define png_snprintf(s1,n,fmt,x1) png_sprintf(s1,fmt,x1)
-# define png_snprintf2(s1,n,fmt,x1,x2) png_sprintf(s1,fmt,x1,x2)
-# define png_snprintf6(s1,n,fmt,x1,x2,x3,x4,x5,x6) \
- png_sprintf(s1,fmt,x1,x2,x3,x4,x5,x6)
+# define png_isaligned(ptr, type) 0
#endif
+
+/* End of memory model/platform independent support */
/* End of 1.5.0beta36 move from pngconf.h */
/* CONSTANTS and UTILITY MACROS
*/
/* Various modes of operation. Note that after an init, mode is set to
- * zero automatically when the structure is created.
+ * 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
-#define PNG_HAVE_PLTE 0x02
+/* #define PNG_HAVE_IHDR 0x01 (defined in png.h) */
+/* #define PNG_HAVE_PLTE 0x02 (defined in png.h) */
#define PNG_HAVE_IDAT 0x04
-#define PNG_AFTER_IDAT 0x08 /* Have complete zlib datastream */
+/* #define PNG_AFTER_IDAT 0x08 (defined in png.h) */
#define PNG_HAVE_IEND 0x10
#define PNG_HAVE_gAMA 0x20
#define PNG_HAVE_cHRM 0x40
#define PNG_SWAP_BYTES 0x0010
#define PNG_INVERT_MONO 0x0020
#define PNG_QUANTIZE 0x0040
-#define PNG_BACKGROUND 0x0080
+#define PNG_COMPOSE 0x0080 /* Was PNG_BACKGROUND */
#define PNG_BACKGROUND_EXPAND 0x0100
#define PNG_EXPAND_16 0x0200 /* Added to libpng 1.5.2 */
-#define PNG_16_TO_8 0x0400
+#define PNG_16_TO_8 0x0400 /* Becomes 'chop' in 1.5.4 */
#define PNG_RGBA 0x0800
#define PNG_EXPAND 0x1000
#define PNG_GAMMA 0x2000
#define PNG_GRAY_TO_RGB 0x4000
-#define PNG_FILLER 0x8000L
-#define PNG_PACKSWAP 0x10000L
-#define PNG_SWAP_ALPHA 0x20000L
-#define PNG_STRIP_ALPHA 0x40000L
-#define PNG_INVERT_ALPHA 0x80000L
-#define PNG_USER_TRANSFORM 0x100000L
-#define PNG_RGB_TO_GRAY_ERR 0x200000L
-#define PNG_RGB_TO_GRAY_WARN 0x400000L
-#define PNG_RGB_TO_GRAY 0x600000L /* two bits, RGB_TO_GRAY_ERR|WARN */
- /* 0x800000L Unused */
-#define PNG_ADD_ALPHA 0x1000000L /* Added to libpng-1.2.7 */
-#define PNG_EXPAND_tRNS 0x2000000L /* Added to libpng-1.2.9 */
- /* 0x4000000L unused */
- /* 0x8000000L unused */
- /* 0x10000000L unused */
- /* 0x20000000L unused */
- /* 0x40000000L unused */
-
+#define PNG_FILLER 0x8000
+#define PNG_PACKSWAP 0x10000
+#define PNG_SWAP_ALPHA 0x20000
+#define PNG_STRIP_ALPHA 0x40000
+#define PNG_INVERT_ALPHA 0x80000
+#define PNG_USER_TRANSFORM 0x100000
+#define PNG_RGB_TO_GRAY_ERR 0x200000
+#define PNG_RGB_TO_GRAY_WARN 0x400000
+#define PNG_RGB_TO_GRAY 0x600000 /* two bits, RGB_TO_GRAY_ERR|WARN */
+#define PNG_ENCODE_ALPHA 0x800000 /* Added to libpng-1.5.4 */
+#define PNG_ADD_ALPHA 0x1000000 /* Added to libpng-1.2.7 */
+#define PNG_EXPAND_tRNS 0x2000000 /* Added to libpng-1.2.9 */
+#define PNG_SCALE_16_TO_8 0x4000000 /* Added to libpng-1.5.4 */
+ /* 0x8000000 unused */
+ /* 0x10000000 unused */
+ /* 0x20000000 unused */
+ /* 0x40000000 unused */
/* Flags for png_create_struct */
#define PNG_STRUCT_PNG 0x0001
#define PNG_STRUCT_INFO 0x0002
#define PNG_FLAG_CRC_ANCILLARY_NOWARN 0x0200
#define PNG_FLAG_CRC_CRITICAL_USE 0x0400
#define PNG_FLAG_CRC_CRITICAL_IGNORE 0x0800
- /* 0x1000 unused */
- /* 0x2000 unused */
- /* 0x4000 unused */
-#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000L
-#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000L
-#define PNG_FLAG_LIBRARY_MISMATCH 0x20000L
-#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000L
-#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000L
-#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000L
- /* 0x200000L unused */
- /* 0x400000L unused */
-#define PNG_FLAG_BENIGN_ERRORS_WARN 0x800000L /* Added to libpng-1.4.0 */
- /* 0x1000000L unused */
- /* 0x2000000L unused */
- /* 0x4000000L unused */
- /* 0x8000000L unused */
- /* 0x10000000L unused */
- /* 0x20000000L unused */
- /* 0x40000000L unused */
+#define PNG_FLAG_ASSUME_sRGB 0x1000 /* Added to libpng-1.5.4 */
+#define PNG_FLAG_OPTIMIZE_ALPHA 0x2000 /* Added to libpng-1.5.4 */
+#define PNG_FLAG_DETECT_UNINITIALIZED 0x4000 /* Added to libpng-1.5.4 */
+#define PNG_FLAG_KEEP_UNKNOWN_CHUNKS 0x8000
+#define PNG_FLAG_KEEP_UNSAFE_CHUNKS 0x10000
+#define PNG_FLAG_LIBRARY_MISMATCH 0x20000
+#define PNG_FLAG_STRIP_ERROR_NUMBERS 0x40000
+#define PNG_FLAG_STRIP_ERROR_TEXT 0x80000
+#define PNG_FLAG_MALLOC_NULL_MEM_OK 0x100000
+ /* 0x200000 unused */
+ /* 0x400000 unused */
+#define PNG_FLAG_BENIGN_ERRORS_WARN 0x800000 /* Added to libpng-1.4.0 */
+#define PNG_FLAG_ZTXT_CUSTOM_STRATEGY 0x1000000 /* 5 lines added */
+#define PNG_FLAG_ZTXT_CUSTOM_LEVEL 0x2000000 /* to libpng-1.5.4 */
+#define PNG_FLAG_ZTXT_CUSTOM_MEM_LEVEL 0x4000000
+#define PNG_FLAG_ZTXT_CUSTOM_WINDOW_BITS 0x8000000
+#define PNG_FLAG_ZTXT_CUSTOM_METHOD 0x10000000
+ /* 0x20000000 unused */
+ /* 0x40000000 unused */
#define PNG_FLAG_CRC_ANCILLARY_MASK (PNG_FLAG_CRC_ANCILLARY_USE | \
PNG_FLAG_CRC_ANCILLARY_NOWARN)
#endif
#endif
-/* Constant strings for known chunk types. If you need to add a chunk,
- * define the name here, and add an invocation of the macro wherever it's
- * needed.
+/* Constants for known chunk types. If you need to add a chunk, define the name
+ * here. For historical reasons these constants have the form png_<name>; i.e.
+ * the prefix is lower case. Please use decimal values as the parameters to
+ * match the ISO PNG specification and to avoid relying on the C locale
+ * interpretation of character values.
+ *
+ * Prior to 1.5.6 these constants were strings, as of 1.5.6 png_uint_32 values
+ * are computed and a new macro (PNG_STRING_FROM_CHUNK) added to allow a string
+ * to be generated if required.
+ *
+ * PNG_32b correctly produces a value shifted by up to 24 bits, even on
+ * architectures where (int) is only 16 bits.
*/
-#define PNG_IHDR PNG_CONST png_byte png_IHDR[5] = { 73, 72, 68, 82, '\0'}
-#define PNG_IDAT PNG_CONST png_byte png_IDAT[5] = { 73, 68, 65, 84, '\0'}
-#define PNG_IEND PNG_CONST png_byte png_IEND[5] = { 73, 69, 78, 68, '\0'}
-#define PNG_PLTE PNG_CONST png_byte png_PLTE[5] = { 80, 76, 84, 69, '\0'}
-#define PNG_bKGD PNG_CONST png_byte png_bKGD[5] = { 98, 75, 71, 68, '\0'}
-#define PNG_cHRM PNG_CONST png_byte png_cHRM[5] = { 99, 72, 82, 77, '\0'}
-#define PNG_gAMA PNG_CONST png_byte png_gAMA[5] = {103, 65, 77, 65, '\0'}
-#define PNG_hIST PNG_CONST png_byte png_hIST[5] = {104, 73, 83, 84, '\0'}
-#define PNG_iCCP PNG_CONST png_byte png_iCCP[5] = {105, 67, 67, 80, '\0'}
-#define PNG_iTXt PNG_CONST png_byte png_iTXt[5] = {105, 84, 88, 116, '\0'}
-#define PNG_oFFs PNG_CONST png_byte png_oFFs[5] = {111, 70, 70, 115, '\0'}
-#define PNG_pCAL PNG_CONST png_byte png_pCAL[5] = {112, 67, 65, 76, '\0'}
-#define PNG_sCAL PNG_CONST png_byte png_sCAL[5] = {115, 67, 65, 76, '\0'}
-#define PNG_pHYs PNG_CONST png_byte png_pHYs[5] = {112, 72, 89, 115, '\0'}
-#define PNG_sBIT PNG_CONST png_byte png_sBIT[5] = {115, 66, 73, 84, '\0'}
-#define PNG_sPLT PNG_CONST png_byte png_sPLT[5] = {115, 80, 76, 84, '\0'}
-#define PNG_sRGB PNG_CONST png_byte png_sRGB[5] = {115, 82, 71, 66, '\0'}
-#define PNG_sTER PNG_CONST png_byte png_sTER[5] = {115, 84, 69, 82, '\0'}
-#define PNG_tEXt PNG_CONST png_byte png_tEXt[5] = {116, 69, 88, 116, '\0'}
-#define PNG_tIME PNG_CONST png_byte png_tIME[5] = {116, 73, 77, 69, '\0'}
-#define PNG_tRNS PNG_CONST png_byte png_tRNS[5] = {116, 82, 78, 83, '\0'}
-#define PNG_zTXt PNG_CONST png_byte png_zTXt[5] = {122, 84, 88, 116, '\0'}
+#define PNG_32b(b,s) ((png_uint_32)(b) << (s))
+#define PNG_CHUNK(b1,b2,b3,b4) \
+ (PNG_32b(b1,24) | PNG_32b(b2,16) | PNG_32b(b3,8) | PNG_32b(b4,0))
+
+#define png_IHDR PNG_CHUNK( 73, 72, 68, 82)
+#define png_IDAT PNG_CHUNK( 73, 68, 65, 84)
+#define png_IEND PNG_CHUNK( 73, 69, 78, 68)
+#define png_PLTE PNG_CHUNK( 80, 76, 84, 69)
+#define png_bKGD PNG_CHUNK( 98, 75, 71, 68)
+#define png_cHRM PNG_CHUNK( 99, 72, 82, 77)
+#define png_gAMA PNG_CHUNK(103, 65, 77, 65)
+#define png_hIST PNG_CHUNK(104, 73, 83, 84)
+#define png_iCCP PNG_CHUNK(105, 67, 67, 80)
+#define png_iTXt PNG_CHUNK(105, 84, 88, 116)
+#define png_oFFs PNG_CHUNK(111, 70, 70, 115)
+#define png_pCAL PNG_CHUNK(112, 67, 65, 76)
+#define png_sCAL PNG_CHUNK(115, 67, 65, 76)
+#define png_pHYs PNG_CHUNK(112, 72, 89, 115)
+#define png_sBIT PNG_CHUNK(115, 66, 73, 84)
+#define png_sPLT PNG_CHUNK(115, 80, 76, 84)
+#define png_sRGB PNG_CHUNK(115, 82, 71, 66)
+#define png_sTER PNG_CHUNK(115, 84, 69, 82)
+#define png_tEXt PNG_CHUNK(116, 69, 88, 116)
+#define png_tIME PNG_CHUNK(116, 73, 77, 69)
+#define png_tRNS PNG_CHUNK(116, 82, 78, 83)
+#define png_zTXt PNG_CHUNK(122, 84, 88, 116)
+
+/* The following will work on (signed char*) strings, whereas the get_uint_32
+ * macro will fail on top-bit-set values because of the sign extension.
+ */
+#define PNG_CHUNK_FROM_STRING(s)\
+ PNG_CHUNK(0xff&(s)[0], 0xff&(s)[1], 0xff&(s)[2], 0xff&(s)[3])
+
+/* This uses (char), not (png_byte) to avoid warnings on systems where (char) is
+ * signed and the argument is a (char[]) This macro will fail miserably on
+ * systems where (char) is more than 8 bits.
+ */
+#define PNG_STRING_FROM_CHUNK(s,c)\
+ (void)(((char*)(s))[0]=(char)((c)>>24), ((char*)(s))[1]=(char)((c)>>16),\
+ ((char*)(s))[2]=(char)((c)>>8), ((char*)(s))[3]=(char)((c)))
+
+/* Do the same but terminate with a null character. */
+#define PNG_CSTRING_FROM_CHUNK(s,c)\
+ (void)(PNG_STRING_FROM_CHUNK(s,c), ((char*)(s))[4] = 0)
+
+/* Test on flag values as defined in the spec (section 5.4): */
+#define PNG_CHUNK_ANCILLIARY(c) (1 & ((c) >> 29))
+#define PNG_CHUNK_CRITICAL(c) (!PNG_CHUNK_ANCILLIARY(c))
+#define PNG_CHUNK_PRIVATE(c) (1 & ((c) >> 21))
+#define PNG_CHUNK_RESERVED(c) (1 & ((c) >> 13))
+#define PNG_CHUNK_SAFE_TO_COPY(c) (1 & ((c) >> 5))
+
+/* Gamma values (new at libpng-1.5.4): */
+#define PNG_GAMMA_MAC_OLD 151724 /* Assume '1.8' is really 2.2/1.45! */
+#define PNG_GAMMA_MAC_INVERSE 65909
+#define PNG_GAMMA_sRGB_INVERSE 45455
/* Inhibit C++ name-mangling for libpng functions but not for system calls. */
* be found in the files where the functions are located.
*/
+/* Check the user version string for compatibility, returns false if the version
+ * numbers aren't compatible.
+ */
+PNG_EXTERN int png_user_version_check(png_structp png_ptr,
+ png_const_charp user_png_ver);
+
/* Allocate memory for an internal libpng struct */
PNG_EXTERN PNG_FUNCTION(png_voidp,png_create_struct,PNGARG((int type)),
PNG_ALLOCATED);
png_size_t length));
/* Decompress data in a chunk that uses compression */
-#if defined(PNG_zTXt_SUPPORTED) || defined(PNG_iTXt_SUPPORTED) || \
- defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED)
+#if defined(PNG_READ_COMPRESSED_TEXT_SUPPORTED)
PNG_EXTERN void png_decompress_chunk PNGARG((png_structp png_ptr,
int comp_type, png_size_t chunklength, png_size_t prefix_length,
png_size_t *data_length));
png_const_uint_16p hist, int num_hist));
#endif
+/* Chunks that have keywords */
#if defined(PNG_WRITE_TEXT_SUPPORTED) || defined(PNG_WRITE_pCAL_SUPPORTED) || \
defined(PNG_WRITE_iCCP_SUPPORTED) || defined(PNG_WRITE_sPLT_SUPPORTED)
PNG_EXTERN png_size_t png_check_keyword PNGARG((png_structp png_ptr,
/* Internal use only. Called before first row of data */
PNG_EXTERN void png_write_start_row PNGARG((png_structp png_ptr));
-/* Combine a row of data, dealing with alpha, etc. if requested */
+/* Combine a row of data, dealing with alpha, etc. if requested. 'row' is an
+ * array of png_ptr->width pixels. If the image is not interlaced or this
+ * is the final pass this just does a png_memcpy, otherwise the "display" flag
+ * is used to determine whether to copy pixels that are not in the current pass.
+ *
+ * Because 'png_do_read_interlace' (below) replicates pixels this allows this
+ * function to achieve the documented 'blocky' appearance during interlaced read
+ * if display is 1 and the 'sparkle' appearance, where existing pixels in 'row'
+ * are not changed if they are not in the current pass, when display is 0.
+ *
+ * 'display' must be 0 or 1, otherwise the memcpy will be done regardless.
+ *
+ * The API always reads from the png_struct row buffer and always assumes that
+ * it is full width (png_do_read_interlace has already been called.)
+ *
+ * This function is only ever used to write to row buffers provided by the
+ * caller of the relevant libpng API and the row must have already been
+ * transformed by the read transformations.
+ *
+ * The PNG_USE_COMPILE_TIME_MASKS option causes generation of pre-computed
+ * bitmasks for use within the code, otherwise runtime generated masks are used.
+ * The default is compile time masks.
+ */
+#ifndef PNG_USE_COMPILE_TIME_MASKS
+# define PNG_USE_COMPILE_TIME_MASKS 1
+#endif
PNG_EXTERN void png_combine_row PNGARG((png_structp png_ptr, png_bytep row,
- int mask));
+ int display));
#ifdef PNG_READ_INTERLACING_SUPPORTED
-/* Expand an interlaced row */
-/* OLD pre-1.0.9 interface:
+/* Expand an interlaced row: the 'row_info' describes the pass data that has
+ * been read in and must correspond to the pixels in 'row', the pixels are
+ * expanded (moved apart) in 'row' to match the final layout, when doing this
+ * the pixels are *replicated* to the intervening space. This is essential for
+ * the correct operation of png_combine_row, above.
+ */
PNG_EXTERN void png_do_read_interlace PNGARG((png_row_infop row_info,
png_bytep row, int pass, png_uint_32 transformations));
- */
-PNG_EXTERN void png_do_read_interlace PNGARG((png_structp png_ptr));
#endif
/* GRR TO DO (2.0 or whenever): simplify other internal calling interfaces */
png_bytep row, int pass));
#endif
-/* Unfilter a row */
-PNG_EXTERN void png_read_filter_row PNGARG((png_structp png_ptr,
- png_row_infop row_info, png_bytep row, png_const_bytep prev_row,
- int filter));
+/* Unfilter a row: check the filter value before calling this, there is no point
+ * calling it for PNG_FILTER_VALUE_NONE.
+ */
+PNG_EXTERN void png_read_filter_row PNGARG((png_structp pp, png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row, int filter));
+
+PNG_EXTERN void png_read_filter_row_up_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_sub3_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_sub4_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_avg3_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_avg4_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_paeth3_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
+PNG_EXTERN void png_read_filter_row_paeth4_neon PNGARG((png_row_infop row_info,
+ png_bytep row, png_const_bytep prev_row));
/* Choose the best filter to use and filter the row data */
PNG_EXTERN void png_write_find_filter PNGARG((png_structp png_ptr,
png_row_infop row_info));
-/* Write out the filtered row. */
-PNG_EXTERN void png_write_filtered_row PNGARG((png_structp png_ptr,
- png_bytep filtered_row));
/* Finish a row while reading, dealing with interlacing passes, etc. */
PNG_EXTERN void png_read_finish_row PNGARG((png_structp png_ptr));
/* Initialize the row buffers, etc. */
PNG_EXTERN void png_read_start_row PNGARG((png_structp png_ptr));
+
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
/* Optional call to update the users info structure */
PNG_EXTERN void png_read_transform_info PNGARG((png_structp png_ptr,
png_infop info_ptr));
+#endif
/* These are the functions that do the transformations */
#ifdef PNG_READ_FILLER_SUPPORTED
png_bytep row));
#endif
-#ifdef PNG_READ_16_TO_8_SUPPORTED
+#ifdef PNG_READ_SCALE_16_TO_8_SUPPORTED
+PNG_EXTERN void png_do_scale_16_to_8 PNGARG((png_row_infop row_info,
+ png_bytep row));
+#endif
+
+#ifdef PNG_READ_STRIP_16_TO_8_SUPPORTED
PNG_EXTERN void png_do_chop PNGARG((png_row_infop row_info,
png_bytep row));
#endif
png_bytep row, png_const_color_8p bit_depth));
#endif
-#ifdef PNG_READ_BACKGROUND_SUPPORTED
-# ifdef PNG_READ_GAMMA_SUPPORTED
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info,
- png_bytep row, png_const_color_16p trans_color,
- png_const_color_16p background, png_const_color_16p background_1,
- png_const_bytep gamma_table, png_const_bytep gamma_from_1,
- png_const_bytep gamma_to_1, png_const_uint_16pp gamma_16,
- png_const_uint_16pp gamma_16_from_1, png_const_uint_16pp gamma_16_to_1,
- int gamma_shift));
-# else
-PNG_EXTERN void png_do_background PNGARG((png_row_infop row_info,
- png_bytep row, png_const_color_16p trans_color,
- png_const_color_16p background));
-# endif
+#if defined(PNG_READ_BACKGROUND_SUPPORTED) ||\
+ defined(PNG_READ_ALPHA_MODE_SUPPORTED)
+PNG_EXTERN void png_do_compose PNGARG((png_row_infop row_info,
+ png_bytep row, png_structp png_ptr));
#endif
#ifdef PNG_READ_GAMMA_SUPPORTED
PNG_EXTERN void png_do_gamma PNGARG((png_row_infop row_info,
- png_bytep row, png_const_bytep gamma_table,
- png_const_uint_16pp gamma_16_table, int gamma_shift));
+ png_bytep row, png_structp png_ptr));
+#endif
+
+#ifdef PNG_READ_ALPHA_MODE_SUPPORTED
+PNG_EXTERN void png_do_encode_alpha PNGARG((png_row_infop row_info,
+ png_bytep row, png_structp png_ptr));
#endif
#ifdef PNG_READ_EXPAND_SUPPORTED
png_uint_32 length));
#endif
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
PNG_EXTERN void png_handle_unknown PNGARG((png_structp png_ptr,
png_infop info_ptr, png_uint_32 length));
+#endif
PNG_EXTERN void png_check_chunk_name PNGARG((png_structp png_ptr,
- png_const_bytep chunk_name));
+ png_uint_32 chunk_name));
+
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
+/* Exactly as png_handle_as_unknown() except that the argument is a 32-bit chunk
+ * name, not a string.
+ */
+PNG_EXTERN int png_chunk_unknown_handling PNGARG((png_structp png_ptr,
+ png_uint_32 chunk_name));
+#endif
/* Handle the transformations for reading and writing */
-PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr));
-PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr));
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
+PNG_EXTERN void png_do_read_transformations PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+#endif
+#ifdef PNG_WRITE_TRANSFORMS_SUPPORTED
+PNG_EXTERN void png_do_write_transformations PNGARG((png_structp png_ptr,
+ png_row_infop row_info));
+#endif
+#ifdef PNG_READ_TRANSFORMS_SUPPORTED
PNG_EXTERN void png_init_read_transformations PNGARG((png_structp png_ptr));
+#endif
#ifdef PNG_PROGRESSIVE_READ_SUPPORTED
PNG_EXTERN void png_push_read_chunk PNGARG((png_structp png_ptr,
unsigned long *hi_product, unsigned long *lo_product));
#endif
+#ifdef PNG_cHRM_SUPPORTED
+/* Added at libpng version 1.5.5 */
+typedef struct png_xy
+{
+ png_fixed_point redx, redy;
+ png_fixed_point greenx, greeny;
+ png_fixed_point bluex, bluey;
+ png_fixed_point whitex, whitey;
+} png_xy;
+
+typedef struct png_XYZ
+{
+ png_fixed_point redX, redY, redZ;
+ png_fixed_point greenX, greenY, greenZ;
+ png_fixed_point blueX, blueY, blueZ;
+} png_XYZ;
+
+/* The conversion APIs return 0 on success, non-zero on a parameter error. They
+ * allow conversion between the above representations of a color encoding. When
+ * converting from XYZ end points to chromaticities the absolute magnitude of
+ * the end points is lost, when converting back the sum of the Y values of the
+ * three end points will be 1.0
+ */
+PNG_EXTERN int png_xy_from_XYZ PNGARG((png_xy *xy, png_XYZ XYZ));
+PNG_EXTERN int png_XYZ_from_xy PNGARG((png_XYZ *XYZ, png_xy xy));
+PNG_EXTERN int png_XYZ_from_xy_checked PNGARG((png_structp png_ptr,
+ png_XYZ *XYZ, png_xy xy));
+#endif
+
/* Added at libpng version 1.4.0 */
PNG_EXTERN void png_check_IHDR PNGARG((png_structp png_ptr,
png_uint_32 width, png_uint_32 height, int bit_depth,
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_EXTERN size_t png_safecat(png_charp buffer, size_t bufsize, size_t pos,
+ png_const_charp string);
+
+/* 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_EXTERN png_charp png_format_number(png_const_charp start, png_charp end,
+ int format, png_alloc_size_t number);
+
+/* 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
+
+/* 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_EXTERN void png_warning_parameter(png_warning_parameters p, int number,
+ png_const_charp string);
+ /* Parameters are limited in size to PNG_WARNING_PARAMETER_SIZE characters,
+ * including the trailing '\0'.
+ */
+PNG_EXTERN void png_warning_parameter_unsigned(png_warning_parameters p,
+ int number, int format, png_alloc_size_t value);
+ /* 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_EXTERN void png_warning_parameter_signed(png_warning_parameters p,
+ int number, int format, png_int_32 value);
+
+PNG_EXTERN void png_formatted_warning(png_structp png_ptr,
+ png_warning_parameters p, png_const_charp message);
+ /* 'message' follows the X/Open approach of using @1, @2 to insert
+ * parameters previously supplied using the above functions. Errors in
+ * specifying the paramters will simple result in garbage substitutions.
+ */
+#endif
+
/* ASCII to FP interfaces, currently only implemented if sCAL
* support is required.
*/
#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_INVALID 128 /* Available for callers as a distinct value */
+#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 initialzed to 0). It returns a result code, as above. There
png_size_t size, int *statep, png_size_tp whereami));
/* This is the same but it checks a complete string and returns true
- * only if it just contains a floating point number.
+ * 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_EXTERN int png_check_fp_string PNGARG((png_const_charp string,
png_size_t size));
png_fixed_point gamma_value));
PNG_EXTERN png_byte png_gamma_8bit_correct PNGARG((unsigned int value,
png_fixed_point gamma_value));
+PNG_EXTERN void png_destroy_gamma_table(png_structp png_ptr);
PNG_EXTERN void png_build_gamma_table PNGARG((png_structp png_ptr,
int bit_depth));
#endif
/* Maintainer: Put new private prototypes here ^ and in libpngpf.3 */
-
#include "pngdebug.h"
#ifdef __cplusplus
projects / apitrace / blobdiff