/* pngerror.c - stub functions for i/o and memory allocation | |
* | |
* Last changed in libpng 1.6.1 [March 28, 2013] | |
* Copyright (c) 1998-2013 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 | |
* | |
* This file provides a location for all error handling. Users who | |
* need special error handling are expected to write replacement functions | |
* and use png_set_error_fn() to use those functions. See the instructions | |
* at each function. | |
*/ | |
#include "pngpriv.h" | |
#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) | |
static PNG_FUNCTION(void, png_default_error,PNGARG((png_const_structrp png_ptr, | |
png_const_charp error_message)),PNG_NORETURN); | |
#ifdef PNG_WARNINGS_SUPPORTED | |
static void /* PRIVATE */ | |
png_default_warning PNGARG((png_const_structrp png_ptr, | |
png_const_charp warning_message)); | |
#endif /* PNG_WARNINGS_SUPPORTED */ | |
/* This function is called whenever there is a fatal error. This function | |
* should not be changed. If there is a need to handle errors differently, | |
* you should supply a replacement error function and use png_set_error_fn() | |
* to replace the error function at run-time. | |
*/ | |
#ifdef PNG_ERROR_TEXT_SUPPORTED | |
PNG_FUNCTION(void,PNGAPI | |
png_error,(png_const_structrp png_ptr, png_const_charp error_message), | |
PNG_NORETURN) | |
{ | |
#ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
char msg[16]; | |
if (png_ptr != NULL) | |
{ | |
if (png_ptr->flags& | |
(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) | |
{ | |
if (*error_message == PNG_LITERAL_SHARP) | |
{ | |
/* Strip "#nnnn " from beginning of error message. */ | |
int offset; | |
for (offset = 1; offset<15; offset++) | |
if (error_message[offset] == ' ') | |
break; | |
if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT) | |
{ | |
int i; | |
for (i = 0; i < offset - 1; i++) | |
msg[i] = error_message[i + 1]; | |
msg[i - 1] = '\0'; | |
error_message = msg; | |
} | |
else | |
error_message += offset; | |
} | |
else | |
{ | |
if (png_ptr->flags&PNG_FLAG_STRIP_ERROR_TEXT) | |
{ | |
msg[0] = '0'; | |
msg[1] = '\0'; | |
error_message = msg; | |
} | |
} | |
} | |
} | |
#endif | |
if (png_ptr != NULL && png_ptr->error_fn != NULL) | |
(*(png_ptr->error_fn))(png_constcast(png_structrp,png_ptr), | |
error_message); | |
/* If the custom handler doesn't exist, or if it returns, | |
use the default handler, which will not return. */ | |
png_default_error(png_ptr, error_message); | |
} | |
#else | |
PNG_FUNCTION(void,PNGAPI | |
png_err,(png_const_structrp png_ptr),PNG_NORETURN) | |
{ | |
/* Prior to 1.5.2 the error_fn received a NULL pointer, expressed | |
* erroneously as '\0', instead of the empty string "". This was | |
* apparently an error, introduced in libpng-1.2.20, and png_default_error | |
* will crash in this case. | |
*/ | |
if (png_ptr != NULL && png_ptr->error_fn != NULL) | |
(*(png_ptr->error_fn))(png_constcast(png_structrp,png_ptr), ""); | |
/* If the custom handler doesn't exist, or if it returns, | |
use the default handler, which will not return. */ | |
png_default_error(png_ptr, ""); | |
} | |
#endif /* PNG_ERROR_TEXT_SUPPORTED */ | |
/* Utility to safely appends strings to a buffer. This never errors out so | |
* error checking is not required in the caller. | |
*/ | |
size_t | |
png_safecat(png_charp buffer, size_t bufsize, size_t pos, | |
png_const_charp string) | |
{ | |
if (buffer != NULL && pos < bufsize) | |
{ | |
if (string != NULL) | |
while (*string != '\0' && pos < bufsize-1) | |
buffer[pos++] = *string++; | |
buffer[pos] = '\0'; | |
} | |
return pos; | |
} | |
#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. | |
*/ | |
png_charp | |
png_format_number(png_const_charp start, png_charp end, int format, | |
png_alloc_size_t number) | |
{ | |
int count = 0; /* number of digits output */ | |
int mincount = 1; /* minimum number required */ | |
int output = 0; /* digit output (for the fixed point format) */ | |
*--end = '\0'; | |
/* This is written so that the loop always runs at least once, even with | |
* number zero. | |
*/ | |
while (end > start && (number != 0 || count < mincount)) | |
{ | |
static const char digits[] = "0123456789ABCDEF"; | |
switch (format) | |
{ | |
case PNG_NUMBER_FORMAT_fixed: | |
/* Needs five digits (the fraction) */ | |
mincount = 5; | |
if (output || number % 10 != 0) | |
{ | |
*--end = digits[number % 10]; | |
output = 1; | |
} | |
number /= 10; | |
break; | |
case PNG_NUMBER_FORMAT_02u: | |
/* Expects at least 2 digits. */ | |
mincount = 2; | |
/* FALL THROUGH */ | |
case PNG_NUMBER_FORMAT_u: | |
*--end = digits[number % 10]; | |
number /= 10; | |
break; | |
case PNG_NUMBER_FORMAT_02x: | |
/* This format expects at least two digits */ | |
mincount = 2; | |
/* FALL THROUGH */ | |
case PNG_NUMBER_FORMAT_x: | |
*--end = digits[number & 0xf]; | |
number >>= 4; | |
break; | |
default: /* an error */ | |
number = 0; | |
break; | |
} | |
/* Keep track of the number of digits added */ | |
++count; | |
/* Float a fixed number here: */ | |
if (format == PNG_NUMBER_FORMAT_fixed) if (count == 5) if (end > start) | |
{ | |
/* End of the fraction, but maybe nothing was output? In that case | |
* drop the decimal point. If the number is a true zero handle that | |
* here. | |
*/ | |
if (output) | |
*--end = '.'; | |
else if (number == 0) /* and !output */ | |
*--end = '0'; | |
} | |
} | |
return end; | |
} | |
#endif | |
#ifdef PNG_WARNINGS_SUPPORTED | |
/* This function is called whenever there is a non-fatal error. This function | |
* should not be changed. If there is a need to handle warnings differently, | |
* you should supply a replacement warning function and use | |
* png_set_error_fn() to replace the warning function at run-time. | |
*/ | |
void PNGAPI | |
png_warning(png_const_structrp png_ptr, png_const_charp warning_message) | |
{ | |
int offset = 0; | |
if (png_ptr != NULL) | |
{ | |
#ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
if (png_ptr->flags& | |
(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) | |
#endif | |
{ | |
if (*warning_message == PNG_LITERAL_SHARP) | |
{ | |
for (offset = 1; offset < 15; offset++) | |
if (warning_message[offset] == ' ') | |
break; | |
} | |
} | |
} | |
if (png_ptr != NULL && png_ptr->warning_fn != NULL) | |
(*(png_ptr->warning_fn))(png_constcast(png_structrp,png_ptr), | |
warning_message + offset); | |
else | |
png_default_warning(png_ptr, warning_message + offset); | |
} | |
/* These functions support 'formatted' warning messages with up to | |
* PNG_WARNING_PARAMETER_COUNT parameters. In the format string the parameter | |
* is introduced by @<number>, where 'number' starts at 1. This follows the | |
* standard established by X/Open for internationalizable error messages. | |
*/ | |
void | |
png_warning_parameter(png_warning_parameters p, int number, | |
png_const_charp string) | |
{ | |
if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT) | |
(void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string); | |
} | |
void | |
png_warning_parameter_unsigned(png_warning_parameters p, int number, int format, | |
png_alloc_size_t value) | |
{ | |
char buffer[PNG_NUMBER_BUFFER_SIZE]; | |
png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value)); | |
} | |
void | |
png_warning_parameter_signed(png_warning_parameters p, int number, int format, | |
png_int_32 value) | |
{ | |
png_alloc_size_t u; | |
png_charp str; | |
char buffer[PNG_NUMBER_BUFFER_SIZE]; | |
/* Avoid overflow by doing the negate in a png_alloc_size_t: */ | |
u = (png_alloc_size_t)value; | |
if (value < 0) | |
u = ~u + 1; | |
str = PNG_FORMAT_NUMBER(buffer, format, u); | |
if (value < 0 && str > buffer) | |
*--str = '-'; | |
png_warning_parameter(p, number, str); | |
} | |
void | |
png_formatted_warning(png_const_structrp png_ptr, png_warning_parameters p, | |
png_const_charp message) | |
{ | |
/* The internal buffer is just 192 bytes - enough for all our messages, | |
* overflow doesn't happen because this code checks! If someone figures | |
* out how to send us a message longer than 192 bytes, all that will | |
* happen is that the message will be truncated appropriately. | |
*/ | |
size_t i = 0; /* Index in the msg[] buffer: */ | |
char msg[192]; | |
/* Each iteration through the following loop writes at most one character | |
* to msg[i++] then returns here to validate that there is still space for | |
* the trailing '\0'. It may (in the case of a parameter) read more than | |
* one character from message[]; it must check for '\0' and continue to the | |
* test if it finds the end of string. | |
*/ | |
while (i<(sizeof msg)-1 && *message != '\0') | |
{ | |
/* '@' at end of string is now just printed (previously it was skipped); | |
* it is an error in the calling code to terminate the string with @. | |
*/ | |
if (p != NULL && *message == '@' && message[1] != '\0') | |
{ | |
int parameter_char = *++message; /* Consume the '@' */ | |
static const char valid_parameters[] = "123456789"; | |
int parameter = 0; | |
/* Search for the parameter digit, the index in the string is the | |
* parameter to use. | |
*/ | |
while (valid_parameters[parameter] != parameter_char && | |
valid_parameters[parameter] != '\0') | |
++parameter; | |
/* If the parameter digit is out of range it will just get printed. */ | |
if (parameter < PNG_WARNING_PARAMETER_COUNT) | |
{ | |
/* Append this parameter */ | |
png_const_charp parm = p[parameter]; | |
png_const_charp pend = p[parameter] + (sizeof p[parameter]); | |
/* No need to copy the trailing '\0' here, but there is no guarantee | |
* that parm[] has been initialized, so there is no guarantee of a | |
* trailing '\0': | |
*/ | |
while (i<(sizeof msg)-1 && *parm != '\0' && parm < pend) | |
msg[i++] = *parm++; | |
/* Consume the parameter digit too: */ | |
++message; | |
continue; | |
} | |
/* else not a parameter and there is a character after the @ sign; just | |
* copy that. This is known not to be '\0' because of the test above. | |
*/ | |
} | |
/* At this point *message can't be '\0', even in the bad parameter case | |
* above where there is a lone '@' at the end of the message string. | |
*/ | |
msg[i++] = *message++; | |
} | |
/* i is always less than (sizeof msg), so: */ | |
msg[i] = '\0'; | |
/* And this is the formatted message. It may be larger than | |
* PNG_MAX_ERROR_TEXT, but that is only used for 'chunk' errors and these | |
* are not (currently) formatted. | |
*/ | |
png_warning(png_ptr, msg); | |
} | |
#endif /* PNG_WARNINGS_SUPPORTED */ | |
#ifdef PNG_BENIGN_ERRORS_SUPPORTED | |
void PNGAPI | |
png_benign_error(png_const_structrp png_ptr, png_const_charp error_message) | |
{ | |
if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) | |
{ | |
# ifdef PNG_READ_SUPPORTED | |
if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 && | |
png_ptr->chunk_name != 0) | |
png_chunk_warning(png_ptr, error_message); | |
else | |
# endif | |
png_warning(png_ptr, error_message); | |
} | |
else | |
{ | |
# ifdef PNG_READ_SUPPORTED | |
if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 && | |
png_ptr->chunk_name != 0) | |
png_chunk_error(png_ptr, error_message); | |
else | |
# endif | |
png_error(png_ptr, error_message); | |
} | |
} | |
void /* PRIVATE */ | |
png_app_warning(png_const_structrp png_ptr, png_const_charp error_message) | |
{ | |
if (png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN) | |
png_warning(png_ptr, error_message); | |
else | |
png_error(png_ptr, error_message); | |
} | |
void /* PRIVATE */ | |
png_app_error(png_const_structrp png_ptr, png_const_charp error_message) | |
{ | |
if (png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN) | |
png_warning(png_ptr, error_message); | |
else | |
png_error(png_ptr, error_message); | |
} | |
#endif /* BENIGN_ERRORS */ | |
/* These utilities are used internally to build an error message that relates | |
* to the current chunk. The chunk name comes from png_ptr->chunk_name, | |
* this is used to prefix the message. The message is limited in length | |
* to 63 bytes, the name characters are output as hex digits wrapped in [] | |
* if the character is invalid. | |
*/ | |
#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) | |
static PNG_CONST char png_digit[16] = { | |
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', | |
'A', 'B', 'C', 'D', 'E', 'F' | |
}; | |
#define PNG_MAX_ERROR_TEXT 196 /* Currently limited be profile_error in png.c */ | |
#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED) | |
static void /* PRIVATE */ | |
png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp | |
error_message) | |
{ | |
png_uint_32 chunk_name = png_ptr->chunk_name; | |
int iout = 0, ishift = 24; | |
while (ishift >= 0) | |
{ | |
int c = (int)(chunk_name >> ishift) & 0xff; | |
ishift -= 8; | |
if (isnonalpha(c)) | |
{ | |
buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET; | |
buffer[iout++] = png_digit[(c & 0xf0) >> 4]; | |
buffer[iout++] = png_digit[c & 0x0f]; | |
buffer[iout++] = PNG_LITERAL_RIGHT_SQUARE_BRACKET; | |
} | |
else | |
{ | |
buffer[iout++] = (char)c; | |
} | |
} | |
if (error_message == NULL) | |
buffer[iout] = '\0'; | |
else | |
{ | |
int iin = 0; | |
buffer[iout++] = ':'; | |
buffer[iout++] = ' '; | |
while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0') | |
buffer[iout++] = error_message[iin++]; | |
/* iin < PNG_MAX_ERROR_TEXT, so the following is safe: */ | |
buffer[iout] = '\0'; | |
} | |
} | |
#endif /* PNG_WARNINGS_SUPPORTED || PNG_ERROR_TEXT_SUPPORTED */ | |
#if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED) | |
PNG_FUNCTION(void,PNGAPI | |
png_chunk_error,(png_const_structrp png_ptr, png_const_charp error_message), | |
PNG_NORETURN) | |
{ | |
char msg[18+PNG_MAX_ERROR_TEXT]; | |
if (png_ptr == NULL) | |
png_error(png_ptr, error_message); | |
else | |
{ | |
png_format_buffer(png_ptr, msg, error_message); | |
png_error(png_ptr, msg); | |
} | |
} | |
#endif /* PNG_READ_SUPPORTED && PNG_ERROR_TEXT_SUPPORTED */ | |
#ifdef PNG_WARNINGS_SUPPORTED | |
void PNGAPI | |
png_chunk_warning(png_const_structrp png_ptr, png_const_charp warning_message) | |
{ | |
char msg[18+PNG_MAX_ERROR_TEXT]; | |
if (png_ptr == NULL) | |
png_warning(png_ptr, warning_message); | |
else | |
{ | |
png_format_buffer(png_ptr, msg, warning_message); | |
png_warning(png_ptr, msg); | |
} | |
} | |
#endif /* PNG_WARNINGS_SUPPORTED */ | |
#ifdef PNG_READ_SUPPORTED | |
#ifdef PNG_BENIGN_ERRORS_SUPPORTED | |
void PNGAPI | |
png_chunk_benign_error(png_const_structrp png_ptr, png_const_charp | |
error_message) | |
{ | |
if (png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) | |
png_chunk_warning(png_ptr, error_message); | |
else | |
png_chunk_error(png_ptr, error_message); | |
} | |
#endif | |
#endif /* PNG_READ_SUPPORTED */ | |
void /* PRIVATE */ | |
png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error) | |
{ | |
/* This is always supported, but for just read or just write it | |
* unconditionally does the right thing. | |
*/ | |
# if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED) | |
if (png_ptr->mode & PNG_IS_READ_STRUCT) | |
# endif | |
# ifdef PNG_READ_SUPPORTED | |
{ | |
if (error < PNG_CHUNK_ERROR) | |
png_chunk_warning(png_ptr, message); | |
else | |
png_chunk_benign_error(png_ptr, message); | |
} | |
# endif | |
# if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED) | |
else if (!(png_ptr->mode & PNG_IS_READ_STRUCT)) | |
# endif | |
# ifdef PNG_WRITE_SUPPORTED | |
{ | |
if (error < PNG_CHUNK_WRITE_ERROR) | |
png_app_warning(png_ptr, message); | |
else | |
png_app_error(png_ptr, message); | |
} | |
# endif | |
} | |
#ifdef PNG_ERROR_TEXT_SUPPORTED | |
#ifdef PNG_FLOATING_POINT_SUPPORTED | |
PNG_FUNCTION(void, | |
png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN) | |
{ | |
# define fixed_message "fixed point overflow in " | |
# define fixed_message_ln ((sizeof fixed_message)-1) | |
int iin; | |
char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT]; | |
memcpy(msg, fixed_message, fixed_message_ln); | |
iin = 0; | |
if (name != NULL) while (iin < (PNG_MAX_ERROR_TEXT-1) && name[iin] != 0) | |
{ | |
msg[fixed_message_ln + iin] = name[iin]; | |
++iin; | |
} | |
msg[fixed_message_ln + iin] = 0; | |
png_error(png_ptr, msg); | |
} | |
#endif | |
#endif | |
#ifdef PNG_SETJMP_SUPPORTED | |
/* This API only exists if ANSI-C style error handling is used, | |
* otherwise it is necessary for png_default_error to be overridden. | |
*/ | |
jmp_buf* PNGAPI | |
png_set_longjmp_fn(png_structrp png_ptr, png_longjmp_ptr longjmp_fn, | |
size_t jmp_buf_size) | |
{ | |
/* From libpng 1.6.0 the app gets one chance to set a 'jmpbuf_size' value | |
* and it must not change after that. Libpng doesn't care how big the | |
* buffer is, just that it doesn't change. | |
* | |
* If the buffer size is no *larger* than the size of jmp_buf when libpng is | |
* compiled a built in jmp_buf is returned; this preserves the pre-1.6.0 | |
* semantics that this call will not fail. If the size is larger, however, | |
* the buffer is allocated and this may fail, causing the function to return | |
* NULL. | |
*/ | |
if (png_ptr == NULL) | |
return NULL; | |
if (png_ptr->jmp_buf_ptr == NULL) | |
{ | |
png_ptr->jmp_buf_size = 0; /* not allocated */ | |
if (jmp_buf_size <= (sizeof png_ptr->jmp_buf_local)) | |
png_ptr->jmp_buf_ptr = &png_ptr->jmp_buf_local; | |
else | |
{ | |
png_ptr->jmp_buf_ptr = png_voidcast(jmp_buf *, | |
png_malloc_warn(png_ptr, jmp_buf_size)); | |
if (png_ptr->jmp_buf_ptr == NULL) | |
return NULL; /* new NULL return on OOM */ | |
png_ptr->jmp_buf_size = jmp_buf_size; | |
} | |
} | |
else /* Already allocated: check the size */ | |
{ | |
size_t size = png_ptr->jmp_buf_size; | |
if (size == 0) | |
{ | |
size = (sizeof png_ptr->jmp_buf_local); | |
if (png_ptr->jmp_buf_ptr != &png_ptr->jmp_buf_local) | |
{ | |
/* This is an internal error in libpng: somehow we have been left | |
* with a stack allocated jmp_buf when the application regained | |
* control. It's always possible to fix this up, but for the moment | |
* this is a png_error because that makes it easy to detect. | |
*/ | |
png_error(png_ptr, "Libpng jmp_buf still allocated"); | |
/* png_ptr->jmp_buf_ptr = &png_ptr->jmp_buf_local; */ | |
} | |
} | |
if (size != jmp_buf_size) | |
{ | |
png_warning(png_ptr, "Application jmp_buf size changed"); | |
return NULL; /* caller will probably crash: no choice here */ | |
} | |
} | |
/* Finally fill in the function, now we have a satisfactory buffer. It is | |
* valid to change the function on every call. | |
*/ | |
png_ptr->longjmp_fn = longjmp_fn; | |
return png_ptr->jmp_buf_ptr; | |
} | |
void /* PRIVATE */ | |
png_free_jmpbuf(png_structrp png_ptr) | |
{ | |
if (png_ptr != NULL) | |
{ | |
jmp_buf *jb = png_ptr->jmp_buf_ptr; | |
/* A size of 0 is used to indicate a local, stack, allocation of the | |
* pointer; used here and in png.c | |
*/ | |
if (jb != NULL && png_ptr->jmp_buf_size > 0) | |
{ | |
/* This stuff is so that a failure to free the error control structure | |
* does not leave libpng in a state with no valid error handling: the | |
* free always succeeds, if there is an error it gets ignored. | |
*/ | |
if (jb != &png_ptr->jmp_buf_local) | |
{ | |
/* Make an internal, libpng, jmp_buf to return here */ | |
jmp_buf free_jmp_buf; | |
if (!setjmp(free_jmp_buf)) | |
{ | |
png_ptr->jmp_buf_ptr = &free_jmp_buf; /* come back here */ | |
png_ptr->jmp_buf_size = 0; /* stack allocation */ | |
png_ptr->longjmp_fn = longjmp; | |
png_free(png_ptr, jb); /* Return to setjmp on error */ | |
} | |
} | |
} | |
/* *Always* cancel everything out: */ | |
png_ptr->jmp_buf_size = 0; | |
png_ptr->jmp_buf_ptr = NULL; | |
png_ptr->longjmp_fn = 0; | |
} | |
} | |
#endif | |
/* This is the default error handling function. Note that replacements for | |
* this function MUST NOT RETURN, or the program will likely crash. This | |
* function is used by default, or if the program supplies NULL for the | |
* error function pointer in png_set_error_fn(). | |
*/ | |
static PNG_FUNCTION(void /* PRIVATE */, | |
png_default_error,(png_const_structrp png_ptr, png_const_charp error_message), | |
PNG_NORETURN) | |
{ | |
#ifdef PNG_CONSOLE_IO_SUPPORTED | |
#ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
/* Check on NULL only added in 1.5.4 */ | |
if (error_message != NULL && *error_message == PNG_LITERAL_SHARP) | |
{ | |
/* Strip "#nnnn " from beginning of error message. */ | |
int offset; | |
char error_number[16]; | |
for (offset = 0; offset<15; offset++) | |
{ | |
error_number[offset] = error_message[offset + 1]; | |
if (error_message[offset] == ' ') | |
break; | |
} | |
if ((offset > 1) && (offset < 15)) | |
{ | |
error_number[offset - 1] = '\0'; | |
fprintf(stderr, "libpng error no. %s: %s", | |
error_number, error_message + offset + 1); | |
fprintf(stderr, PNG_STRING_NEWLINE); | |
} | |
else | |
{ | |
fprintf(stderr, "libpng error: %s, offset=%d", | |
error_message, offset); | |
fprintf(stderr, PNG_STRING_NEWLINE); | |
} | |
} | |
else | |
#endif | |
{ | |
fprintf(stderr, "libpng error: %s", error_message ? error_message : | |
"undefined"); | |
fprintf(stderr, PNG_STRING_NEWLINE); | |
} | |
#else | |
PNG_UNUSED(error_message) /* Make compiler happy */ | |
#endif | |
png_longjmp(png_ptr, 1); | |
} | |
PNG_FUNCTION(void,PNGAPI | |
png_longjmp,(png_const_structrp png_ptr, int val),PNG_NORETURN) | |
{ | |
#ifdef PNG_SETJMP_SUPPORTED | |
if (png_ptr && png_ptr->longjmp_fn && png_ptr->jmp_buf_ptr) | |
png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val); | |
#endif | |
/* Here if not setjmp support or if png_ptr is null. */ | |
PNG_ABORT(); | |
} | |
#ifdef PNG_WARNINGS_SUPPORTED | |
/* This function is called when there is a warning, but the library thinks | |
* it can continue anyway. Replacement functions don't have to do anything | |
* here if you don't want them to. In the default configuration, png_ptr is | |
* not used, but it is passed in case it may be useful. | |
*/ | |
static void /* PRIVATE */ | |
png_default_warning(png_const_structrp png_ptr, png_const_charp warning_message) | |
{ | |
#ifdef PNG_CONSOLE_IO_SUPPORTED | |
# ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
if (*warning_message == PNG_LITERAL_SHARP) | |
{ | |
int offset; | |
char warning_number[16]; | |
for (offset = 0; offset < 15; offset++) | |
{ | |
warning_number[offset] = warning_message[offset + 1]; | |
if (warning_message[offset] == ' ') | |
break; | |
} | |
if ((offset > 1) && (offset < 15)) | |
{ | |
warning_number[offset + 1] = '\0'; | |
fprintf(stderr, "libpng warning no. %s: %s", | |
warning_number, warning_message + offset); | |
fprintf(stderr, PNG_STRING_NEWLINE); | |
} | |
else | |
{ | |
fprintf(stderr, "libpng warning: %s", | |
warning_message); | |
fprintf(stderr, PNG_STRING_NEWLINE); | |
} | |
} | |
else | |
# endif | |
{ | |
fprintf(stderr, "libpng warning: %s", warning_message); | |
fprintf(stderr, PNG_STRING_NEWLINE); | |
} | |
#else | |
PNG_UNUSED(warning_message) /* Make compiler happy */ | |
#endif | |
PNG_UNUSED(png_ptr) /* Make compiler happy */ | |
} | |
#endif /* PNG_WARNINGS_SUPPORTED */ | |
/* This function is called when the application wants to use another method | |
* of handling errors and warnings. Note that the error function MUST NOT | |
* return to the calling routine or serious problems will occur. The return | |
* method used in the default routine calls longjmp(png_ptr->jmp_buf_ptr, 1) | |
*/ | |
void PNGAPI | |
png_set_error_fn(png_structrp png_ptr, png_voidp error_ptr, | |
png_error_ptr error_fn, png_error_ptr warning_fn) | |
{ | |
if (png_ptr == NULL) | |
return; | |
png_ptr->error_ptr = error_ptr; | |
png_ptr->error_fn = error_fn; | |
#ifdef PNG_WARNINGS_SUPPORTED | |
png_ptr->warning_fn = warning_fn; | |
#else | |
PNG_UNUSED(warning_fn) | |
#endif | |
} | |
/* This function returns a pointer to the error_ptr associated with the user | |
* functions. The application should free any memory associated with this | |
* pointer before png_write_destroy and png_read_destroy are called. | |
*/ | |
png_voidp PNGAPI | |
png_get_error_ptr(png_const_structrp png_ptr) | |
{ | |
if (png_ptr == NULL) | |
return NULL; | |
return ((png_voidp)png_ptr->error_ptr); | |
} | |
#ifdef PNG_ERROR_NUMBERS_SUPPORTED | |
void PNGAPI | |
png_set_strip_error_numbers(png_structrp png_ptr, png_uint_32 strip_mode) | |
{ | |
if (png_ptr != NULL) | |
{ | |
png_ptr->flags &= | |
((~(PNG_FLAG_STRIP_ERROR_NUMBERS | | |
PNG_FLAG_STRIP_ERROR_TEXT))&strip_mode); | |
} | |
} | |
#endif | |
#if defined(PNG_SIMPLIFIED_READ_SUPPORTED) ||\ | |
defined(PNG_SIMPLIFIED_WRITE_SUPPORTED) | |
/* Currently the above both depend on SETJMP_SUPPORTED, however it would be | |
* possible to implement without setjmp support just so long as there is some | |
* way to handle the error return here: | |
*/ | |
PNG_FUNCTION(void /* PRIVATE */, | |
png_safe_error,(png_structp png_nonconst_ptr, png_const_charp error_message), | |
PNG_NORETURN) | |
{ | |
const png_const_structrp png_ptr = png_nonconst_ptr; | |
png_imagep image = png_voidcast(png_imagep, png_ptr->error_ptr); | |
/* An error is always logged here, overwriting anything (typically a warning) | |
* that is already there: | |
*/ | |
if (image != NULL) | |
{ | |
png_safecat(image->message, (sizeof image->message), 0, error_message); | |
image->warning_or_error |= PNG_IMAGE_ERROR; | |
/* Retrieve the jmp_buf from within the png_control, making this work for | |
* C++ compilation too is pretty tricky: C++ wants a pointer to the first | |
* element of a jmp_buf, but C doesn't tell us the type of that. | |
*/ | |
if (image->opaque != NULL && image->opaque->error_buf != NULL) | |
longjmp(png_control_jmp_buf(image->opaque), 1); | |
/* Missing longjmp buffer, the following is to help debugging: */ | |
{ | |
size_t pos = png_safecat(image->message, (sizeof image->message), 0, | |
"bad longjmp: "); | |
png_safecat(image->message, (sizeof image->message), pos, | |
error_message); | |
} | |
} | |
/* Here on an internal programming error. */ | |
abort(); | |
} | |
#ifdef PNG_WARNINGS_SUPPORTED | |
void /* PRIVATE */ | |
png_safe_warning(png_structp png_nonconst_ptr, png_const_charp warning_message) | |
{ | |
const png_const_structrp png_ptr = png_nonconst_ptr; | |
png_imagep image = png_voidcast(png_imagep, png_ptr->error_ptr); | |
/* A warning is only logged if there is no prior warning or error. */ | |
if (image->warning_or_error == 0) | |
{ | |
png_safecat(image->message, (sizeof image->message), 0, warning_message); | |
image->warning_or_error |= PNG_IMAGE_WARNING; | |
} | |
} | |
#endif | |
int /* PRIVATE */ | |
png_safe_execute(png_imagep image_in, int (*function)(png_voidp), png_voidp arg) | |
{ | |
volatile png_imagep image = image_in; | |
volatile int result; | |
volatile png_voidp saved_error_buf; | |
jmp_buf safe_jmpbuf; | |
/* Safely execute function(arg) with png_error returning to this function. */ | |
saved_error_buf = image->opaque->error_buf; | |
result = setjmp(safe_jmpbuf) == 0; | |
if (result) | |
{ | |
image->opaque->error_buf = safe_jmpbuf; | |
result = function(arg); | |
} | |
image->opaque->error_buf = saved_error_buf; | |
/* And do the cleanup prior to any failure return. */ | |
if (!result) | |
png_image_free(image); | |
return result; | |
} | |
#endif /* SIMPLIFIED READ/WRITE */ | |
#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */ |