/* pngerror.c - stub functions for i/o and memory allocation * * libpng version 1.2.8 - December 3, 2004 * For conditions of distribution and use, see copyright notice in png.h * Copyright (c) 1998-2004 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 error_message));static void /* PRIVATE */png_default_warning PNGARG((png_structp png_ptr,  png_const_charp warning_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 PNGAPIpng_error(png_structp png_ptr, png_const_charp error_message){#ifdef PNG_ERROR_NUMBERS_SUPPORTED   char msg[16];   if (png_ptr->flags&(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))   {     if (*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]='\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_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);}/* 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 PNGAPIpng_warning(png_structp png_ptr, png_const_charp warning_message){   int offset = 0;#ifdef PNG_ERROR_NUMBERS_SUPPORTED   if (png_ptr->flags&(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT))#endif   {     if (*warning_message == '#')     {         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_ptr, warning_message+offset);   else      png_default_warning(png_ptr, warning_message+offset);}/* 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'};static void /* PRIVATE */png_format_buffer(png_structp png_ptr, png_charp buffer, png_const_charp   error_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 (error_message == NULL)      buffer[iout] = 0;   else   {      buffer[iout++] = ':';      buffer[iout++] = ' ';      png_strncpy(buffer+iout, error_message, 63);      buffer[iout+63] = 0;   }}void PNGAPIpng_chunk_error(png_structp png_ptr, png_const_charp error_message){   char msg[18+64];   png_format_buffer(png_ptr, msg, error_message);   png_error(png_ptr, msg);}void PNGAPIpng_chunk_warning(png_structp png_ptr, png_const_charp warning_message){   char msg[18+64];   png_format_buffer(png_ptr, msg, warning_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 error_message){#ifndef PNG_NO_CONSOLE_IO#ifdef PNG_ERROR_NUMBERS_SUPPORTED   if (*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\n", error_number,          error_message+offset);     }     else       fprintf(stderr, "libpng error: %s, offset=%d\n", error_message,offset);   }   else#endif   fprintf(stderr, "libpng error: %s\n", error_message);#endif#ifdef PNG_SETJMP_SUPPORTED#  ifdef USE_FAR_KEYWORD   {      jmp_buf jmpbuf;      png_memcpy(jmpbuf,png_ptr->jmpbuf,png_sizeof(jmp_buf));      longjmp(jmpbuf, 1);   }#  else   longjmp(png_ptr->jmpbuf, 1);# endif#else   /* make compiler happy */ ;   if (png_ptr)   PNG_ABORT();#endif#ifdef PNG_NO_CONSOLE_IO   /* make compiler happy */ ;   if (&error_message != NULL)      return;#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 warning_message){#ifndef PNG_NO_CONSOLE_IO#  ifdef PNG_ERROR_NUMBERS_SUPPORTED   if (*warning_message == '#')   {     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\n", warning_number,          warning_message+offset);     }     else       fprintf(stderr, "libpng warning: %s\n", warning_message);   }   else#  endif     fprintf(stderr, "libpng warning: %s\n", warning_message);#else   /* make compiler happy */ ;   if (warning_message)     return;#endif   /* make compiler happy */ ;   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 PNGAPIpng_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 PNGAPIpng_get_error_ptr(png_structp png_ptr){   return ((png_voidp)png_ptr->error_ptr);}#ifdef PNG_ERROR_NUMBERS_SUPPORTEDvoid PNGAPIpng_set_strip_error_numbers(png_structp 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