| |
| /* pngerror.c - stub functions for i/o and memory allocation |
| |
| libpng 1.0 beta 3 - version 0.89 |
| For conditions of distribution and use, see copyright notice in png.h |
| Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc. |
| May 25, 1996 |
| |
| This file provides a location for all error handling. Users which |
| 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 png_default_error PNGARG((png_structp png_ptr, |
| png_const_charp message)); |
| static void 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 |
| png_error(png_structp png_ptr, png_const_charp message) |
| { |
| if (png_ptr->error_fn) |
| (*(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 |
| png_warning(png_structp png_ptr, png_const_charp message) |
| { |
| if (png_ptr->warning_fn) |
| (*(png_ptr->warning_fn))(png_ptr, message); |
| else |
| png_default_warning(png_ptr, message); |
| } |
| |
| /* 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 |
| png_default_error(png_structp png_ptr, png_const_charp message) |
| { |
| #ifndef PNG_NO_STDIO |
| fprintf(stderr, "libpng error: %s\n", message); |
| #endif |
| |
| #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 |
| } |
| |
| /* 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 to. In the default configuration, png_ptr is |
| not used, but it is passed in case it may be useful. */ |
| static void |
| png_default_warning(png_structp png_ptr, png_const_charp message) |
| { |
| if (!png_ptr) |
| return; |
| |
| #ifndef PNG_NO_STDIO |
| fprintf(stderr, "libpng warning: %s\n", message); |
| #endif |
| } |
| |
| /* 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 |
| 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 |
| png_get_error_ptr(png_structp png_ptr) |
| { |
| return png_ptr->error_ptr; |
| } |
| |
| |
| |