mirror of
https://github.com/reactos/reactos.git
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964 lines
28 KiB
C
964 lines
28 KiB
C
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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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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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/* 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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# 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_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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# 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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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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while (iin < PNG_MAX_ERROR_TEXT-1 && error_message[iin] != '\0')
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buffer[iout++] = error_message[iin++];
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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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#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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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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#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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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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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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#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)
|
|
{
|
|
if ((png_ptr->flags & PNG_FLAG_BENIGN_ERRORS_WARN) != 0)
|
|
png_chunk_warning(png_ptr, error_message);
|
|
|
|
else
|
|
png_chunk_error(png_ptr, error_message);
|
|
|
|
# ifndef PNG_ERROR_TEXT_SUPPORTED
|
|
PNG_UNUSED(error_message)
|
|
# endif
|
|
}
|
|
#endif
|
|
#endif /* READ */
|
|
|
|
void /* PRIVATE */
|
|
png_chunk_report(png_const_structrp png_ptr, png_const_charp message, int error)
|
|
{
|
|
# ifndef PNG_WARNINGS_SUPPORTED
|
|
PNG_UNUSED(message)
|
|
# endif
|
|
|
|
/* 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) != 0)
|
|
# 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) == 0)
|
|
# 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)
|
|
unsigned 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 != 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 */
|