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963 lines
28 KiB
963 lines
28 KiB
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/* pngerror.c - stub functions for i/o and memory allocation |
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* |
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* Copyright (c) 2018 Cosmin Truta |
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* Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson |
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* Copyright (c) 1996-1997 Andreas Dilger |
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* Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc. |
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* |
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* This code is released under the libpng license. |
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* For conditions of distribution and use, see the disclaimer |
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* and license in png.h |
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* |
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* This file provides a location for all error handling. Users who |
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* need special error handling are expected to write replacement functions |
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* and use png_set_error_fn() to use those functions. See the instructions |
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* at each function. |
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*/ |
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#include "pngpriv.h" |
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#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) |
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|
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static PNG_FUNCTION(void, png_default_error,PNGARG((png_const_structrp png_ptr, |
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png_const_charp error_message)),PNG_NORETURN); |
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#ifdef PNG_WARNINGS_SUPPORTED |
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static void /* PRIVATE */ |
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png_default_warning PNGARG((png_const_structrp png_ptr, |
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png_const_charp warning_message)); |
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#endif /* WARNINGS */ |
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/* This function is called whenever there is a fatal error. This function |
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* should not be changed. If there is a need to handle errors differently, |
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* you should supply a replacement error function and use png_set_error_fn() |
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* to replace the error function at run-time. |
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*/ |
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#ifdef PNG_ERROR_TEXT_SUPPORTED |
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PNG_FUNCTION(void,PNGAPI |
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png_error,(png_const_structrp png_ptr, png_const_charp error_message), |
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PNG_NORETURN) |
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{ |
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#ifdef PNG_ERROR_NUMBERS_SUPPORTED |
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char msg[16]; |
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if (png_ptr != NULL) |
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{ |
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if ((png_ptr->flags & |
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(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0) |
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{ |
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if (*error_message == PNG_LITERAL_SHARP) |
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{ |
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/* Strip "#nnnn " from beginning of error message. */ |
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int offset; |
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for (offset = 1; offset<15; offset++) |
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if (error_message[offset] == ' ') |
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break; |
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if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0) |
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{ |
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int i; |
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for (i = 0; i < offset - 1; i++) |
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msg[i] = error_message[i + 1]; |
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msg[i - 1] = '\0'; |
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error_message = msg; |
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} |
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else |
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error_message += offset; |
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} |
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else |
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{ |
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if ((png_ptr->flags & PNG_FLAG_STRIP_ERROR_TEXT) != 0) |
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{ |
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msg[0] = '0'; |
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msg[1] = '\0'; |
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error_message = msg; |
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} |
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} |
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} |
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} |
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#endif |
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if (png_ptr != NULL && png_ptr->error_fn != NULL) |
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(*(png_ptr->error_fn))(png_constcast(png_structrp,png_ptr), |
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error_message); |
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/* If the custom handler doesn't exist, or if it returns, |
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use the default handler, which will not return. */ |
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png_default_error(png_ptr, error_message); |
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} |
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#else |
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PNG_FUNCTION(void,PNGAPI |
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png_err,(png_const_structrp png_ptr),PNG_NORETURN) |
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{ |
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/* Prior to 1.5.2 the error_fn received a NULL pointer, expressed |
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* erroneously as '\0', instead of the empty string "". This was |
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* apparently an error, introduced in libpng-1.2.20, and png_default_error |
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* will crash in this case. |
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*/ |
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if (png_ptr != NULL && png_ptr->error_fn != NULL) |
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(*(png_ptr->error_fn))(png_constcast(png_structrp,png_ptr), ""); |
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/* If the custom handler doesn't exist, or if it returns, |
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use the default handler, which will not return. */ |
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png_default_error(png_ptr, ""); |
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} |
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#endif /* ERROR_TEXT */ |
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/* Utility to safely appends strings to a buffer. This never errors out so |
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* error checking is not required in the caller. |
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*/ |
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size_t |
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png_safecat(png_charp buffer, size_t bufsize, size_t pos, |
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png_const_charp string) |
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{ |
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if (buffer != NULL && pos < bufsize) |
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{ |
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if (string != NULL) |
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while (*string != '\0' && pos < bufsize-1) |
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buffer[pos++] = *string++; |
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buffer[pos] = '\0'; |
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} |
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return pos; |
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} |
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#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_TIME_RFC1123_SUPPORTED) |
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/* Utility to dump an unsigned value into a buffer, given a start pointer and |
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* and end pointer (which should point just *beyond* the end of the buffer!) |
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* Returns the pointer to the start of the formatted string. |
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*/ |
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png_charp |
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png_format_number(png_const_charp start, png_charp end, int format, |
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png_alloc_size_t number) |
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{ |
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int count = 0; /* number of digits output */ |
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int mincount = 1; /* minimum number required */ |
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int output = 0; /* digit output (for the fixed point format) */ |
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*--end = '\0'; |
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/* This is written so that the loop always runs at least once, even with |
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* number zero. |
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*/ |
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while (end > start && (number != 0 || count < mincount)) |
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{ |
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static const char digits[] = "0123456789ABCDEF"; |
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switch (format) |
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{ |
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case PNG_NUMBER_FORMAT_fixed: |
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/* Needs five digits (the fraction) */ |
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mincount = 5; |
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if (output != 0 || number % 10 != 0) |
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{ |
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*--end = digits[number % 10]; |
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output = 1; |
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} |
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number /= 10; |
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break; |
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case PNG_NUMBER_FORMAT_02u: |
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/* Expects at least 2 digits. */ |
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mincount = 2; |
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/* FALLTHROUGH */ |
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case PNG_NUMBER_FORMAT_u: |
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*--end = digits[number % 10]; |
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number /= 10; |
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break; |
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case PNG_NUMBER_FORMAT_02x: |
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/* This format expects at least two digits */ |
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mincount = 2; |
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/* FALLTHROUGH */ |
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case PNG_NUMBER_FORMAT_x: |
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*--end = digits[number & 0xf]; |
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number >>= 4; |
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break; |
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default: /* an error */ |
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number = 0; |
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break; |
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} |
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/* Keep track of the number of digits added */ |
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++count; |
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/* Float a fixed number here: */ |
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if ((format == PNG_NUMBER_FORMAT_fixed) && (count == 5) && (end > start)) |
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{ |
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/* End of the fraction, but maybe nothing was output? In that case |
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* drop the decimal point. If the number is a true zero handle that |
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* here. |
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*/ |
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if (output != 0) |
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*--end = '.'; |
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else if (number == 0) /* and !output */ |
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*--end = '0'; |
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} |
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} |
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return end; |
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} |
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#endif |
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#ifdef PNG_WARNINGS_SUPPORTED |
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/* This function is called whenever there is a non-fatal error. This function |
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* should not be changed. If there is a need to handle warnings differently, |
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* you should supply a replacement warning function and use |
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* png_set_error_fn() to replace the warning function at run-time. |
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*/ |
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void PNGAPI |
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png_warning(png_const_structrp png_ptr, png_const_charp warning_message) |
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{ |
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int offset = 0; |
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if (png_ptr != NULL) |
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{ |
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#ifdef PNG_ERROR_NUMBERS_SUPPORTED |
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if ((png_ptr->flags & |
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(PNG_FLAG_STRIP_ERROR_NUMBERS|PNG_FLAG_STRIP_ERROR_TEXT)) != 0) |
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#endif |
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{ |
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if (*warning_message == PNG_LITERAL_SHARP) |
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{ |
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for (offset = 1; offset < 15; offset++) |
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if (warning_message[offset] == ' ') |
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break; |
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} |
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} |
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} |
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if (png_ptr != NULL && png_ptr->warning_fn != NULL) |
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(*(png_ptr->warning_fn))(png_constcast(png_structrp,png_ptr), |
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warning_message + offset); |
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else |
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png_default_warning(png_ptr, warning_message + offset); |
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} |
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/* These functions support 'formatted' warning messages with up to |
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* PNG_WARNING_PARAMETER_COUNT parameters. In the format string the parameter |
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* is introduced by @<number>, where 'number' starts at 1. This follows the |
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* standard established by X/Open for internationalizable error messages. |
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*/ |
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void |
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png_warning_parameter(png_warning_parameters p, int number, |
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png_const_charp string) |
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{ |
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if (number > 0 && number <= PNG_WARNING_PARAMETER_COUNT) |
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(void)png_safecat(p[number-1], (sizeof p[number-1]), 0, string); |
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} |
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void |
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png_warning_parameter_unsigned(png_warning_parameters p, int number, int format, |
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png_alloc_size_t value) |
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{ |
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char buffer[PNG_NUMBER_BUFFER_SIZE]; |
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png_warning_parameter(p, number, PNG_FORMAT_NUMBER(buffer, format, value)); |
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} |
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void |
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png_warning_parameter_signed(png_warning_parameters p, int number, int format, |
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png_int_32 value) |
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{ |
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png_alloc_size_t u; |
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png_charp str; |
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char buffer[PNG_NUMBER_BUFFER_SIZE]; |
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/* Avoid overflow by doing the negate in a png_alloc_size_t: */ |
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u = (png_alloc_size_t)value; |
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if (value < 0) |
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u = ~u + 1; |
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str = PNG_FORMAT_NUMBER(buffer, format, u); |
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if (value < 0 && str > buffer) |
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*--str = '-'; |
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png_warning_parameter(p, number, str); |
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} |
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void |
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png_formatted_warning(png_const_structrp png_ptr, png_warning_parameters p, |
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png_const_charp message) |
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{ |
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/* The internal buffer is just 192 bytes - enough for all our messages, |
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* overflow doesn't happen because this code checks! If someone figures |
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* out how to send us a message longer than 192 bytes, all that will |
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* happen is that the message will be truncated appropriately. |
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*/ |
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size_t i = 0; /* Index in the msg[] buffer: */ |
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char msg[192]; |
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/* Each iteration through the following loop writes at most one character |
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* to msg[i++] then returns here to validate that there is still space for |
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* the trailing '\0'. It may (in the case of a parameter) read more than |
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* one character from message[]; it must check for '\0' and continue to the |
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* test if it finds the end of string. |
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*/ |
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while (i<(sizeof msg)-1 && *message != '\0') |
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{ |
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/* '@' at end of string is now just printed (previously it was skipped); |
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* it is an error in the calling code to terminate the string with @. |
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*/ |
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if (p != NULL && *message == '@' && message[1] != '\0') |
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{ |
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int parameter_char = *++message; /* Consume the '@' */ |
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static const char valid_parameters[] = "123456789"; |
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int parameter = 0; |
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/* Search for the parameter digit, the index in the string is the |
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* parameter to use. |
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*/ |
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while (valid_parameters[parameter] != parameter_char && |
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valid_parameters[parameter] != '\0') |
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++parameter; |
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/* If the parameter digit is out of range it will just get printed. */ |
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if (parameter < PNG_WARNING_PARAMETER_COUNT) |
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{ |
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/* Append this parameter */ |
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png_const_charp parm = p[parameter]; |
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png_const_charp pend = p[parameter] + (sizeof p[parameter]); |
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/* No need to copy the trailing '\0' here, but there is no guarantee |
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* that parm[] has been initialized, so there is no guarantee of a |
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* trailing '\0': |
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*/ |
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while (i<(sizeof msg)-1 && *parm != '\0' && parm < pend) |
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msg[i++] = *parm++; |
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/* Consume the parameter digit too: */ |
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++message; |
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continue; |
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} |
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/* else not a parameter and there is a character after the @ sign; just |
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* copy that. This is known not to be '\0' because of the test above. |
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*/ |
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} |
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/* At this point *message can't be '\0', even in the bad parameter case |
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* above where there is a lone '@' at the end of the message string. |
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*/ |
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msg[i++] = *message++; |
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} |
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/* i is always less than (sizeof msg), so: */ |
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msg[i] = '\0'; |
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|
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/* And this is the formatted message. It may be larger than |
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* PNG_MAX_ERROR_TEXT, but that is only used for 'chunk' errors and these |
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* are not (currently) formatted. |
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*/ |
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png_warning(png_ptr, msg); |
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} |
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#endif /* WARNINGS */ |
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#ifdef PNG_BENIGN_ERRORS_SUPPORTED |
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void PNGAPI |
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png_benign_error(png_const_structrp png_ptr, png_const_charp error_message) |
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{ |
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if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0) |
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{ |
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# ifdef PNG_READ_SUPPORTED |
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if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 && |
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png_ptr->chunk_name != 0) |
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png_chunk_warning(png_ptr, error_message); |
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else |
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# endif |
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png_warning(png_ptr, error_message); |
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} |
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else |
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{ |
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# ifdef PNG_READ_SUPPORTED |
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if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0 && |
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png_ptr->chunk_name != 0) |
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png_chunk_error(png_ptr, error_message); |
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else |
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# endif |
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png_error(png_ptr, error_message); |
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} |
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|
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# ifndef PNG_ERROR_TEXT_SUPPORTED |
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PNG_UNUSED(error_message) |
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# endif |
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} |
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|
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void /* PRIVATE */ |
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png_app_warning(png_const_structrp png_ptr, png_const_charp error_message) |
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{ |
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if ((png_ptr->flags & PNG_FLAG_APP_WARNINGS_WARN) != 0) |
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png_warning(png_ptr, error_message); |
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else |
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png_error(png_ptr, error_message); |
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|
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# ifndef PNG_ERROR_TEXT_SUPPORTED |
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PNG_UNUSED(error_message) |
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# endif |
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} |
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void /* PRIVATE */ |
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png_app_error(png_const_structrp png_ptr, png_const_charp error_message) |
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{ |
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if ((png_ptr->flags & PNG_FLAG_APP_ERRORS_WARN) != 0) |
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png_warning(png_ptr, error_message); |
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else |
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png_error(png_ptr, error_message); |
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# ifndef PNG_ERROR_TEXT_SUPPORTED |
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PNG_UNUSED(error_message) |
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# endif |
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} |
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#endif /* BENIGN_ERRORS */ |
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#define PNG_MAX_ERROR_TEXT 196 /* Currently limited by profile_error in png.c */ |
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#if defined(PNG_WARNINGS_SUPPORTED) || \ |
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(defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED)) |
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/* These utilities are used internally to build an error message that relates |
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* to the current chunk. The chunk name comes from png_ptr->chunk_name, |
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* which is used to prefix the message. The message is limited in length |
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* to 63 bytes. The name characters are output as hex digits wrapped in [] |
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* if the character is invalid. |
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*/ |
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#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97)) |
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static const char png_digit[16] = { |
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'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', |
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'A', 'B', 'C', 'D', 'E', 'F' |
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}; |
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static void /* PRIVATE */ |
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png_format_buffer(png_const_structrp png_ptr, png_charp buffer, png_const_charp |
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error_message) |
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{ |
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png_uint_32 chunk_name = png_ptr->chunk_name; |
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int iout = 0, ishift = 24; |
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while (ishift >= 0) |
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{ |
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int c = (int)(chunk_name >> ishift) & 0xff; |
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ishift -= 8; |
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if (isnonalpha(c) != 0) |
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{ |
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buffer[iout++] = PNG_LITERAL_LEFT_SQUARE_BRACKET; |
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buffer[iout++] = png_digit[(c & 0xf0) >> 4]; |
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buffer[iout++] = png_digit[c & 0x0f]; |
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buffer[iout++] = PNG_LITERAL_RIGHT_SQUARE_BRACKET; |
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} |
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else |
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{ |
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buffer[iout++] = (char)c; |
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} |
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} |
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|
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if (error_message == NULL) |
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buffer[iout] = '\0'; |
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else |
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{ |
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int iin = 0; |
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buffer[iout++] = ':'; |
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buffer[iout++] = ' '; |
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|
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while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0') |
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buffer[iout++] = error_message[iin++]; |
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|
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/* iin < PNG_MAX_ERROR_TEXT, so the following is safe: */ |
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buffer[iout] = '\0'; |
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} |
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} |
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#endif /* WARNINGS || ERROR_TEXT */ |
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|
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#if defined(PNG_READ_SUPPORTED) && defined(PNG_ERROR_TEXT_SUPPORTED) |
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PNG_FUNCTION(void,PNGAPI |
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png_chunk_error,(png_const_structrp png_ptr, png_const_charp error_message), |
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PNG_NORETURN) |
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{ |
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char msg[18+PNG_MAX_ERROR_TEXT]; |
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if (png_ptr == NULL) |
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png_error(png_ptr, error_message); |
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|
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else |
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{ |
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png_format_buffer(png_ptr, msg, error_message); |
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png_error(png_ptr, msg); |
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} |
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} |
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#endif /* READ && ERROR_TEXT */ |
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|
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#ifdef PNG_WARNINGS_SUPPORTED |
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void PNGAPI |
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png_chunk_warning(png_const_structrp png_ptr, png_const_charp warning_message) |
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{ |
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char msg[18+PNG_MAX_ERROR_TEXT]; |
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if (png_ptr == NULL) |
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png_warning(png_ptr, warning_message); |
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|
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else |
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{ |
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png_format_buffer(png_ptr, msg, warning_message); |
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png_warning(png_ptr, msg); |
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} |
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} |
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#endif /* WARNINGS */ |
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|
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#ifdef PNG_READ_SUPPORTED |
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#ifdef PNG_BENIGN_ERRORS_SUPPORTED |
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void PNGAPI |
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png_chunk_benign_error(png_const_structrp png_ptr, png_const_charp |
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error_message) |
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{ |
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if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0) |
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png_chunk_warning(png_ptr, error_message); |
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|
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else |
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png_chunk_error(png_ptr, error_message); |
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|
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# ifndef PNG_ERROR_TEXT_SUPPORTED |
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PNG_UNUSED(error_message) |
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# endif |
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} |
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#endif |
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#endif /* READ */ |
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|
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void /* PRIVATE */ |
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png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error) |
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{ |
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# ifndef PNG_WARNINGS_SUPPORTED |
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PNG_UNUSED(message) |
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# endif |
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|
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/* This is always supported, but for just read or just write it |
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* unconditionally does the right thing. |
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*/ |
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# if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED) |
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if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0) |
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# endif |
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|
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# ifdef PNG_READ_SUPPORTED |
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{ |
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if (error < PNG_CHUNK_ERROR) |
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png_chunk_warning(png_ptr, message); |
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|
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else |
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png_chunk_benign_error(png_ptr, message); |
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} |
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# endif |
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|
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# if defined(PNG_READ_SUPPORTED) && defined(PNG_WRITE_SUPPORTED) |
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else if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0) |
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# endif |
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|
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# ifdef PNG_WRITE_SUPPORTED |
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{ |
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if (error < PNG_CHUNK_WRITE_ERROR) |
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png_app_warning(png_ptr, message); |
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|
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else |
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png_app_error(png_ptr, message); |
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} |
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# endif |
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} |
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|
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#ifdef PNG_ERROR_TEXT_SUPPORTED |
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#ifdef PNG_FLOATING_POINT_SUPPORTED |
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PNG_FUNCTION(void, |
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png_fixed_error,(png_const_structrp png_ptr, png_const_charp name),PNG_NORETURN) |
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{ |
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# define fixed_message "fixed point overflow in " |
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# define fixed_message_ln ((sizeof fixed_message)-1) |
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unsigned int iin; |
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char msg[fixed_message_ln+PNG_MAX_ERROR_TEXT]; |
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memcpy(msg, fixed_message, fixed_message_ln); |
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iin = 0; |
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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 != NULL && png_ptr->longjmp_fn != NULL && |
|
png_ptr->jmp_buf_ptr != NULL) |
|
png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val); |
|
#else |
|
PNG_UNUSED(png_ptr) |
|
PNG_UNUSED(val) |
|
#endif |
|
|
|
/* If control reaches this point, png_longjmp() must not return. The only |
|
* choice is to terminate the whole process (or maybe the thread); to do |
|
* this the ANSI-C abort() function is used unless a different method is |
|
* implemented by overriding the default configuration setting for |
|
* PNG_ABORT(). |
|
*/ |
|
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 /* WARNINGS */ |
|
|
|
/* 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 */, (PNGCBAPI |
|
png_safe_error),(png_structp png_nonconst_ptr, png_const_charp error_message), |
|
PNG_NORETURN) |
|
{ |
|
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 */ PNGCBAPI |
|
png_safe_warning(png_structp png_nonconst_ptr, png_const_charp warning_message) |
|
{ |
|
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 != 0) |
|
{ |
|
|
|
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 == 0) |
|
png_image_free(image); |
|
|
|
return result; |
|
} |
|
#endif /* SIMPLIFIED READ || SIMPLIFIED_WRITE */ |
|
#endif /* READ || WRITE */
|
|
|