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/* pngerror.c - stub functions for i/o and memory allocation
*
* libpng 1.0.9beta9 - January 15, 2001
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1998, 1999, 2000, 2001 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 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.
*/
#define PNG_INTERNAL
#include "png.h"
static void /* PRIVATE */
png_default_error PNGARG((png_structp png_ptr,
png_const_charp message));
static void /* PRIVATE */
png_default_warning PNGARG((png_structp png_ptr,
png_const_charp message));
/* 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.
*/
void PNGAPI
png_error(png_structp png_ptr, png_const_charp message)
{
if (png_ptr->error_fn != NULL)
(*(png_ptr->error_fn))(png_ptr, message);
/* if the following returns or doesn't exist, use the default function,
which will not return */
png_default_error(png_ptr, message);
}
/* 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_structp png_ptr, png_const_charp message)
{
if (png_ptr->warning_fn != NULL)
(*(png_ptr->warning_fn))(png_ptr, message);
else
png_default_warning(png_ptr, message);
}
/* 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) < 41 || (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'
};
static void /* PRIVATE */
png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp message)
{
int iout = 0, iin = 0;
while (iin < 4)
{
int c = png_ptr->chunk_name[iin++];
if (isnonalpha(c))
{
buffer[iout++] = '[';
buffer[iout++] = png_digit[(c & 0xf0) >> 4];
buffer[iout++] = png_digit[c & 0x0f];
buffer[iout++] = ']';
}
else
{
buffer[iout++] = (png_byte)c;
}
}
if (message == NULL)
buffer[iout] = 0;
else
{
buffer[iout++] = ':';
buffer[iout++] = ' ';
png_memcpy(buffer+iout, message, 64);
buffer[iout+63] = 0;
}
}
void PNGAPI
png_chunk_error(png_structp png_ptr, png_const_charp message)
{
char msg[18+64];
png_format_buffer(png_ptr, msg, message);
png_error(png_ptr, msg);
}
void PNGAPI
png_chunk_warning(png_structp png_ptr, png_const_charp message)
{
char msg[16+64];
png_format_buffer(png_ptr, msg, message);
png_warning(png_ptr, msg);
}
/* 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 void /* PRIVATE */
png_default_error(png_structp png_ptr, png_const_charp message)
{
#ifndef PNG_NO_CONSOLE_IO
fprintf(stderr, "libpng error: %s\n", message);
#else
if (message)
/* make compiler happy */ ;
#endif
#ifdef PNG_SETJMP_SUPPORTED
# ifdef USE_FAR_KEYWORD
{
jmp_buf jmpbuf;
png_memcpy(jmpbuf,png_ptr->jmpbuf,sizeof(jmp_buf));
longjmp(jmpbuf, 1);
}
# else
longjmp(png_ptr->jmpbuf, 1);
# endif
#else
if (png_ptr)
/* make compiler happy */ ;
PNG_ABORT();
#endif
}
/* 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_structp png_ptr, png_const_charp message)
{
#ifndef PNG_NO_CONSOLE_IO
fprintf(stderr, "libpng warning: %s\n", message);
#else
if (message)
/* appease compiler */ ;
#endif
if (png_ptr)
return;
}
/* 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->jmpbuf, 1)
*/
void PNGAPI
png_set_error_fn(png_structp png_ptr, png_voidp error_ptr,
png_error_ptr error_fn, png_error_ptr warning_fn)
{
png_ptr->error_ptr = error_ptr;
png_ptr->error_fn = error_fn;
png_ptr->warning_fn = warning_fn;
}
/* 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_structp png_ptr)
{
return ((png_voidp)png_ptr->error_ptr);
}
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