3434 lines
98 KiB
C
3434 lines
98 KiB
C
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/* pngrutil.c - utilities to read a PNG file
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*
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* Last changed in libpng 1.2.45 [July 7, 2011]
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* Copyright (c) 1998-2011 Glenn Randers-Pehrson
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* (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
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* (Version 0.88 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 contains routines that are only called from within
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* libpng itself during the course of reading an image.
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*/
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#define PNG_INTERNAL
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#define PNG_NO_PEDANTIC_WARNINGS
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#include "png.h"
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#ifdef PNG_READ_SUPPORTED
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#if defined(_WIN32_WCE) && (_WIN32_WCE<0x500)
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# define WIN32_WCE_OLD
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#endif
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#ifdef PNG_FLOATING_POINT_SUPPORTED
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# ifdef WIN32_WCE_OLD
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/* The strtod() function is not supported on WindowsCE */
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__inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr,
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char **endptr)
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{
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double result = 0;
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int len;
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wchar_t *str, *end;
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len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0);
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str = (wchar_t *)png_malloc(png_ptr, len * png_sizeof(wchar_t));
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if ( NULL != str )
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{
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MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len);
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result = wcstod(str, &end);
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len = WideCharToMultiByte(CP_ACP, 0, end, -1, NULL, 0, NULL, NULL);
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*endptr = (char *)nptr + (png_strlen(nptr) - len + 1);
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png_free(png_ptr, str);
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}
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return result;
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}
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# else
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# define png_strtod(p,a,b) strtod(a,b)
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# endif
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#endif
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png_uint_32 PNGAPI
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png_get_uint_31(png_structp png_ptr, png_bytep buf)
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{
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#ifdef PNG_READ_BIG_ENDIAN_SUPPORTED
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png_uint_32 i = png_get_uint_32(buf);
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#else
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/* Avoid an extra function call by inlining the result. */
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png_uint_32 i = ((png_uint_32)(*buf) << 24) +
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((png_uint_32)(*(buf + 1)) << 16) +
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((png_uint_32)(*(buf + 2)) << 8) +
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(png_uint_32)(*(buf + 3));
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#endif
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if (i > PNG_UINT_31_MAX)
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png_error(png_ptr, "PNG unsigned integer out of range.");
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return (i);
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}
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#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
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/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
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png_uint_32 PNGAPI
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png_get_uint_32(png_bytep buf)
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{
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png_uint_32 i = ((png_uint_32)(*buf) << 24) +
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((png_uint_32)(*(buf + 1)) << 16) +
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((png_uint_32)(*(buf + 2)) << 8) +
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(png_uint_32)(*(buf + 3));
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return (i);
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}
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/* Grab a signed 32-bit integer from a buffer in big-endian format. The
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* data is stored in the PNG file in two's complement format, and it is
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* assumed that the machine format for signed integers is the same.
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*/
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png_int_32 PNGAPI
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png_get_int_32(png_bytep buf)
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{
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png_int_32 i = ((png_int_32)(*buf) << 24) +
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((png_int_32)(*(buf + 1)) << 16) +
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((png_int_32)(*(buf + 2)) << 8) +
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(png_int_32)(*(buf + 3));
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return (i);
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}
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/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
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png_uint_16 PNGAPI
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png_get_uint_16(png_bytep buf)
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{
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png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
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(png_uint_16)(*(buf + 1)));
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return (i);
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}
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#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
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/* Read the chunk header (length + type name).
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* Put the type name into png_ptr->chunk_name, and return the length.
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*/
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png_uint_32 /* PRIVATE */
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png_read_chunk_header(png_structp png_ptr)
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{
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png_byte buf[8];
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png_uint_32 length;
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/* Read the length and the chunk name */
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png_read_data(png_ptr, buf, 8);
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length = png_get_uint_31(png_ptr, buf);
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/* Put the chunk name into png_ptr->chunk_name */
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png_memcpy(png_ptr->chunk_name, buf + 4, 4);
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png_debug2(0, "Reading %s chunk, length = %lu",
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png_ptr->chunk_name, length);
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/* Reset the crc and run it over the chunk name */
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png_reset_crc(png_ptr);
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png_calculate_crc(png_ptr, png_ptr->chunk_name, 4);
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/* Check to see if chunk name is valid */
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png_check_chunk_name(png_ptr, png_ptr->chunk_name);
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return length;
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}
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/* Read data, and (optionally) run it through the CRC. */
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void /* PRIVATE */
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png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
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{
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if (png_ptr == NULL)
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return;
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png_read_data(png_ptr, buf, length);
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png_calculate_crc(png_ptr, buf, length);
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}
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#ifdef PNG_INDEX_SUPPORTED
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/* Optionally skip data and then check the CRC. Depending on whether we
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* are reading a ancillary or critical chunk, and how the program has set
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* things up, we may calculate the CRC on the data and print a message.
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* Returns '1' if there was a CRC error, '0' otherwise.
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*/
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int /* PRIVATE */
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png_opt_crc_finish(png_structp png_ptr, png_uint_32 skip, int check_crc)
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{
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png_size_t i;
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png_size_t istop = png_ptr->zbuf_size;
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for (i = (png_size_t)skip; i > istop; i -= istop)
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{
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png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
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}
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if (i)
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{
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png_crc_read(png_ptr, png_ptr->zbuf, i);
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}
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if (png_crc_error(png_ptr))
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{
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if (!check_crc) {
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png_chunk_warning(png_ptr, "CRC error");
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return (1);
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}
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if (((png_ptr->chunk_name[0] & 0x20) && /* Ancillary */
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!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) ||
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(!(png_ptr->chunk_name[0] & 0x20) && /* Critical */
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(png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE)))
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{
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png_chunk_warning(png_ptr, "CRC error");
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}
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else
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{
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png_chunk_error(png_ptr, "CRC error");
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}
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return (1);
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}
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return (0);
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}
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#endif
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/* Optionally skip data and then check the CRC. Depending on whether we
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* are reading a ancillary or critical chunk, and how the program has set
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* things up, we may calculate the CRC on the data and print a message.
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* Returns '1' if there was a CRC error, '0' otherwise.
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*/
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int /* PRIVATE */
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png_crc_finish(png_structp png_ptr, png_uint_32 skip)
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{
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return png_opt_crc_finish(png_ptr, skip, 1);
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}
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/* Compare the CRC stored in the PNG file with that calculated by libpng from
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* the data it has read thus far.
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*/
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int /* PRIVATE */
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png_crc_error(png_structp png_ptr)
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{
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png_byte crc_bytes[4];
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png_uint_32 crc;
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int need_crc = 1;
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if (png_ptr->chunk_name[0] & 0x20) /* ancillary */
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{
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if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
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(PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
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need_crc = 0;
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}
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else /* critical */
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{
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if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
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need_crc = 0;
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}
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png_read_data(png_ptr, crc_bytes, 4);
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if (need_crc)
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{
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crc = png_get_uint_32(crc_bytes);
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return ((int)(crc != png_ptr->crc));
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}
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else
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return (0);
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}
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#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \
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defined(PNG_READ_iCCP_SUPPORTED)
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static png_size_t
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png_inflate(png_structp png_ptr, const png_byte *data, png_size_t size,
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png_bytep output, png_size_t output_size)
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{
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png_size_t count = 0;
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png_ptr->zstream.next_in = (png_bytep)data; /* const_cast: VALID */
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png_ptr->zstream.avail_in = size;
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while (1)
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{
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int ret, avail;
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/* Reset the output buffer each time round - we empty it
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* after every inflate call.
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*/
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png_ptr->zstream.next_out = png_ptr->zbuf;
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png_ptr->zstream.avail_out = png_ptr->zbuf_size;
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ret = inflate(&png_ptr->zstream, Z_NO_FLUSH);
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avail = png_ptr->zbuf_size - png_ptr->zstream.avail_out;
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/* First copy/count any new output - but only if we didn't
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* get an error code.
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*/
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if ((ret == Z_OK || ret == Z_STREAM_END) && avail > 0)
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{
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if (output != 0 && output_size > count)
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{
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int copy = output_size - count;
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if (avail < copy) copy = avail;
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png_memcpy(output + count, png_ptr->zbuf, copy);
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}
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count += avail;
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}
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if (ret == Z_OK)
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continue;
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/* Termination conditions - always reset the zstream, it
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* must be left in inflateInit state.
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*/
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png_ptr->zstream.avail_in = 0;
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inflateReset(&png_ptr->zstream);
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if (ret == Z_STREAM_END)
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return count; /* NOTE: may be zero. */
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/* Now handle the error codes - the API always returns 0
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* and the error message is dumped into the uncompressed
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* buffer if available.
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*/
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{
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PNG_CONST char *msg;
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if (png_ptr->zstream.msg != 0)
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msg = png_ptr->zstream.msg;
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else
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{
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#if defined(PNG_STDIO_SUPPORTED) && !defined(_WIN32_WCE)
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char umsg[52];
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switch (ret)
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{
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case Z_BUF_ERROR:
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msg = "Buffer error in compressed datastream in %s chunk";
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break;
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case Z_DATA_ERROR:
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msg = "Data error in compressed datastream in %s chunk";
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break;
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default:
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msg = "Incomplete compressed datastream in %s chunk";
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break;
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}
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png_snprintf(umsg, sizeof umsg, msg, png_ptr->chunk_name);
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msg = umsg;
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#else
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msg = "Damaged compressed datastream in chunk other than IDAT";
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#endif
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}
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png_warning(png_ptr, msg);
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}
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/* 0 means an error - notice that this code simple ignores
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* zero length compressed chunks as a result.
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*/
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return 0;
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}
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}
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/*
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* Decompress trailing data in a chunk. The assumption is that chunkdata
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* points at an allocated area holding the contents of a chunk with a
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* trailing compressed part. What we get back is an allocated area
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* holding the original prefix part and an uncompressed version of the
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* trailing part (the malloc area passed in is freed).
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*/
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void /* PRIVATE */
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png_decompress_chunk(png_structp png_ptr, int comp_type,
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png_size_t chunklength,
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png_size_t prefix_size, png_size_t *newlength)
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{
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/* The caller should guarantee this */
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if (prefix_size > chunklength)
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{
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/* The recovery is to delete the chunk. */
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png_warning(png_ptr, "invalid chunklength");
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prefix_size = 0; /* To delete everything */
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}
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else if (comp_type == PNG_COMPRESSION_TYPE_BASE)
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{
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png_size_t expanded_size = png_inflate(png_ptr,
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(png_bytep)(png_ptr->chunkdata + prefix_size),
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chunklength - prefix_size,
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0/*output*/, 0/*output size*/);
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/* Now check the limits on this chunk - if the limit fails the
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* compressed data will be removed, the prefix will remain.
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*/
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#ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
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if (png_ptr->user_chunk_malloc_max &&
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(prefix_size + expanded_size >= png_ptr->user_chunk_malloc_max - 1))
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#else
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# ifdef PNG_USER_CHUNK_MALLOC_MAX
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if ((PNG_USER_CHUNK_MALLOC_MAX > 0) &&
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prefix_size + expanded_size >= PNG_USER_CHUNK_MALLOC_MAX - 1)
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# endif
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#endif
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png_warning(png_ptr, "Exceeded size limit while expanding chunk");
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/* If the size is zero either there was an error and a message
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* has already been output (warning) or the size really is zero
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* and we have nothing to do - the code will exit through the
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* error case below.
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*/
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#if defined(PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED) || \
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defined(PNG_USER_CHUNK_MALLOC_MAX)
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else
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#endif
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if (expanded_size > 0)
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{
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/* Success (maybe) - really uncompress the chunk. */
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png_size_t new_size = 0;
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png_charp text = png_malloc_warn(png_ptr,
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prefix_size + expanded_size + 1);
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if (text != NULL)
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{
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png_memcpy(text, png_ptr->chunkdata, prefix_size);
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new_size = png_inflate(png_ptr,
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(png_bytep)(png_ptr->chunkdata + prefix_size),
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chunklength - prefix_size,
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(png_bytep)(text + prefix_size), expanded_size);
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text[prefix_size + expanded_size] = 0; /* just in case */
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if (new_size == expanded_size)
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{
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png_free(png_ptr, png_ptr->chunkdata);
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png_ptr->chunkdata = text;
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*newlength = prefix_size + expanded_size;
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return; /* The success return! */
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}
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png_warning(png_ptr, "png_inflate logic error");
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png_free(png_ptr, text);
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}
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else
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png_warning(png_ptr, "Not enough memory to decompress chunk.");
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}
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}
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else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
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{
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#if defined(PNG_STDIO_SUPPORTED) && !defined(_WIN32_WCE)
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char umsg[50];
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png_snprintf(umsg, sizeof umsg, "Unknown zTXt compression type %d",
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comp_type);
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png_warning(png_ptr, umsg);
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#else
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png_warning(png_ptr, "Unknown zTXt compression type");
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#endif
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/* The recovery is to simply drop the data. */
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}
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/* Generic error return - leave the prefix, delete the compressed
|
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* data, reallocate the chunkdata to remove the potentially large
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* amount of compressed data.
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*/
|
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{
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png_charp text = png_malloc_warn(png_ptr, prefix_size + 1);
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if (text != NULL)
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{
|
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if (prefix_size > 0)
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png_memcpy(text, png_ptr->chunkdata, prefix_size);
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png_free(png_ptr, png_ptr->chunkdata);
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png_ptr->chunkdata = text;
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/* This is an extra zero in the 'uncompressed' part. */
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*(png_ptr->chunkdata + prefix_size) = 0x00;
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}
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/* Ignore a malloc error here - it is safe. */
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}
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*newlength = prefix_size;
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}
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#endif
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|
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/* Read and check the IDHR chunk */
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void /* PRIVATE */
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png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
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{
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png_byte buf[13];
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png_uint_32 width, height;
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int bit_depth, color_type, compression_type, filter_type;
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int interlace_type;
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|
|
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png_debug(1, "in png_handle_IHDR");
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|
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if (png_ptr->mode & PNG_HAVE_IHDR)
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png_error(png_ptr, "Out of place IHDR");
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|
|
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/* Check the length */
|
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if (length != 13)
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png_error(png_ptr, "Invalid IHDR chunk");
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png_ptr->mode |= PNG_HAVE_IHDR;
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png_crc_read(png_ptr, buf, 13);
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png_crc_finish(png_ptr, 0);
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width = png_get_uint_31(png_ptr, buf);
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height = png_get_uint_31(png_ptr, buf + 4);
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bit_depth = buf[8];
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color_type = buf[9];
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compression_type = buf[10];
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filter_type = buf[11];
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interlace_type = buf[12];
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|
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/* Set internal variables */
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png_ptr->width = width;
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png_ptr->height = height;
|
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png_ptr->bit_depth = (png_byte)bit_depth;
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png_ptr->interlaced = (png_byte)interlace_type;
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png_ptr->color_type = (png_byte)color_type;
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#ifdef PNG_MNG_FEATURES_SUPPORTED
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png_ptr->filter_type = (png_byte)filter_type;
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#endif
|
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png_ptr->compression_type = (png_byte)compression_type;
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|
|
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/* Find number of channels */
|
|
switch (png_ptr->color_type)
|
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{
|
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case PNG_COLOR_TYPE_GRAY:
|
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case PNG_COLOR_TYPE_PALETTE:
|
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png_ptr->channels = 1;
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break;
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|
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case PNG_COLOR_TYPE_RGB:
|
|
png_ptr->channels = 3;
|
|
break;
|
|
|
|
case PNG_COLOR_TYPE_GRAY_ALPHA:
|
|
png_ptr->channels = 2;
|
|
break;
|
|
|
|
case PNG_COLOR_TYPE_RGB_ALPHA:
|
|
png_ptr->channels = 4;
|
|
break;
|
|
}
|
|
|
|
/* Set up other useful info */
|
|
png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth *
|
|
png_ptr->channels);
|
|
png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width);
|
|
png_debug1(3, "bit_depth = %d", png_ptr->bit_depth);
|
|
png_debug1(3, "channels = %d", png_ptr->channels);
|
|
png_debug1(3, "rowbytes = %lu", png_ptr->rowbytes);
|
|
png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,
|
|
color_type, interlace_type, compression_type, filter_type);
|
|
}
|
|
|
|
/* Read and check the palette */
|
|
void /* PRIVATE */
|
|
png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_color palette[PNG_MAX_PALETTE_LENGTH];
|
|
int num, i;
|
|
#ifdef PNG_POINTER_INDEXING_SUPPORTED
|
|
png_colorp pal_ptr;
|
|
#endif
|
|
|
|
png_debug(1, "in png_handle_PLTE");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before PLTE");
|
|
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid PLTE after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
else if (png_ptr->mode & PNG_HAVE_PLTE)
|
|
png_error(png_ptr, "Duplicate PLTE chunk");
|
|
|
|
png_ptr->mode |= PNG_HAVE_PLTE;
|
|
|
|
if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring PLTE chunk in grayscale PNG");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
#ifndef PNG_READ_OPT_PLTE_SUPPORTED
|
|
if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3)
|
|
{
|
|
if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
png_warning(png_ptr, "Invalid palette chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
else
|
|
{
|
|
png_error(png_ptr, "Invalid palette chunk");
|
|
}
|
|
}
|
|
|
|
num = (int)length / 3;
|
|
|
|
#ifdef PNG_POINTER_INDEXING_SUPPORTED
|
|
for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)
|
|
{
|
|
png_byte buf[3];
|
|
|
|
png_crc_read(png_ptr, buf, 3);
|
|
pal_ptr->red = buf[0];
|
|
pal_ptr->green = buf[1];
|
|
pal_ptr->blue = buf[2];
|
|
}
|
|
#else
|
|
for (i = 0; i < num; i++)
|
|
{
|
|
png_byte buf[3];
|
|
|
|
png_crc_read(png_ptr, buf, 3);
|
|
/* Don't depend upon png_color being any order */
|
|
palette[i].red = buf[0];
|
|
palette[i].green = buf[1];
|
|
palette[i].blue = buf[2];
|
|
}
|
|
#endif
|
|
|
|
/* If we actually NEED the PLTE chunk (ie for a paletted image), we do
|
|
* whatever the normal CRC configuration tells us. However, if we
|
|
* have an RGB image, the PLTE can be considered ancillary, so
|
|
* we will act as though it is.
|
|
*/
|
|
#ifndef PNG_READ_OPT_PLTE_SUPPORTED
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
#endif
|
|
{
|
|
png_crc_finish(png_ptr, 0);
|
|
}
|
|
#ifndef PNG_READ_OPT_PLTE_SUPPORTED
|
|
else if (png_crc_error(png_ptr)) /* Only if we have a CRC error */
|
|
{
|
|
/* If we don't want to use the data from an ancillary chunk,
|
|
we have two options: an error abort, or a warning and we
|
|
ignore the data in this chunk (which should be OK, since
|
|
it's considered ancillary for a RGB or RGBA image). */
|
|
if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))
|
|
{
|
|
if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)
|
|
{
|
|
png_chunk_error(png_ptr, "CRC error");
|
|
}
|
|
else
|
|
{
|
|
png_chunk_warning(png_ptr, "CRC error");
|
|
return;
|
|
}
|
|
}
|
|
/* Otherwise, we (optionally) emit a warning and use the chunk. */
|
|
else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN))
|
|
{
|
|
png_chunk_warning(png_ptr, "CRC error");
|
|
}
|
|
}
|
|
#endif
|
|
|
|
png_set_PLTE(png_ptr, info_ptr, palette, num);
|
|
|
|
#ifdef PNG_READ_tRNS_SUPPORTED
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
|
|
{
|
|
if (png_ptr->num_trans > (png_uint_16)num)
|
|
{
|
|
png_warning(png_ptr, "Truncating incorrect tRNS chunk length");
|
|
png_ptr->num_trans = (png_uint_16)num;
|
|
}
|
|
if (info_ptr->num_trans > (png_uint_16)num)
|
|
{
|
|
png_warning(png_ptr, "Truncating incorrect info tRNS chunk length");
|
|
info_ptr->num_trans = (png_uint_16)num;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
}
|
|
|
|
void /* PRIVATE */
|
|
png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_debug(1, "in png_handle_IEND");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT))
|
|
{
|
|
png_error(png_ptr, "No image in file");
|
|
}
|
|
|
|
png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND);
|
|
|
|
if (length != 0)
|
|
{
|
|
png_warning(png_ptr, "Incorrect IEND chunk length");
|
|
}
|
|
png_crc_finish(png_ptr, length);
|
|
|
|
info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */
|
|
}
|
|
|
|
#ifdef PNG_READ_gAMA_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_fixed_point igamma;
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
float file_gamma;
|
|
#endif
|
|
png_byte buf[4];
|
|
|
|
png_debug(1, "in png_handle_gAMA");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before gAMA");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid gAMA after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (png_ptr->mode & PNG_HAVE_PLTE)
|
|
/* Should be an error, but we can cope with it */
|
|
png_warning(png_ptr, "Out of place gAMA chunk");
|
|
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)
|
|
#ifdef PNG_READ_sRGB_SUPPORTED
|
|
&& !(info_ptr->valid & PNG_INFO_sRGB)
|
|
#endif
|
|
)
|
|
{
|
|
png_warning(png_ptr, "Duplicate gAMA chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (length != 4)
|
|
{
|
|
png_warning(png_ptr, "Incorrect gAMA chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 4);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
igamma = (png_fixed_point)png_get_uint_32(buf);
|
|
/* Check for zero gamma */
|
|
if (igamma == 0)
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring gAMA chunk with gamma=0");
|
|
return;
|
|
}
|
|
|
|
#ifdef PNG_READ_sRGB_SUPPORTED
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
|
|
if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring incorrect gAMA value when sRGB is also present");
|
|
#ifdef PNG_CONSOLE_IO_SUPPORTED
|
|
fprintf(stderr, "gamma = (%d/100000)", (int)igamma);
|
|
#endif
|
|
return;
|
|
}
|
|
#endif /* PNG_READ_sRGB_SUPPORTED */
|
|
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
file_gamma = (float)igamma / (float)100000.0;
|
|
# ifdef PNG_READ_GAMMA_SUPPORTED
|
|
png_ptr->gamma = file_gamma;
|
|
# endif
|
|
png_set_gAMA(png_ptr, info_ptr, file_gamma);
|
|
#endif
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
png_set_gAMA_fixed(png_ptr, info_ptr, igamma);
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_sBIT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_size_t truelen;
|
|
png_byte buf[4];
|
|
|
|
png_debug(1, "in png_handle_sBIT");
|
|
|
|
buf[0] = buf[1] = buf[2] = buf[3] = 0;
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before sBIT");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid sBIT after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (png_ptr->mode & PNG_HAVE_PLTE)
|
|
{
|
|
/* Should be an error, but we can cope with it */
|
|
png_warning(png_ptr, "Out of place sBIT chunk");
|
|
}
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT))
|
|
{
|
|
png_warning(png_ptr, "Duplicate sBIT chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
truelen = 3;
|
|
else
|
|
truelen = (png_size_t)png_ptr->channels;
|
|
|
|
if (length != truelen || length > 4)
|
|
{
|
|
png_warning(png_ptr, "Incorrect sBIT chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, truelen);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
|
|
{
|
|
png_ptr->sig_bit.red = buf[0];
|
|
png_ptr->sig_bit.green = buf[1];
|
|
png_ptr->sig_bit.blue = buf[2];
|
|
png_ptr->sig_bit.alpha = buf[3];
|
|
}
|
|
else
|
|
{
|
|
png_ptr->sig_bit.gray = buf[0];
|
|
png_ptr->sig_bit.red = buf[0];
|
|
png_ptr->sig_bit.green = buf[0];
|
|
png_ptr->sig_bit.blue = buf[0];
|
|
png_ptr->sig_bit.alpha = buf[1];
|
|
}
|
|
png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit));
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_cHRM_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_byte buf[32];
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
|
|
#endif
|
|
png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
|
|
int_y_green, int_x_blue, int_y_blue;
|
|
|
|
png_uint_32 uint_x, uint_y;
|
|
|
|
png_debug(1, "in png_handle_cHRM");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before cHRM");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid cHRM after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (png_ptr->mode & PNG_HAVE_PLTE)
|
|
/* Should be an error, but we can cope with it */
|
|
png_warning(png_ptr, "Missing PLTE before cHRM");
|
|
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)
|
|
#ifdef PNG_READ_sRGB_SUPPORTED
|
|
&& !(info_ptr->valid & PNG_INFO_sRGB)
|
|
#endif
|
|
)
|
|
{
|
|
png_warning(png_ptr, "Duplicate cHRM chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (length != 32)
|
|
{
|
|
png_warning(png_ptr, "Incorrect cHRM chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 32);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
uint_x = png_get_uint_32(buf);
|
|
uint_y = png_get_uint_32(buf + 4);
|
|
int_x_white = (png_fixed_point)uint_x;
|
|
int_y_white = (png_fixed_point)uint_y;
|
|
|
|
uint_x = png_get_uint_32(buf + 8);
|
|
uint_y = png_get_uint_32(buf + 12);
|
|
int_x_red = (png_fixed_point)uint_x;
|
|
int_y_red = (png_fixed_point)uint_y;
|
|
|
|
uint_x = png_get_uint_32(buf + 16);
|
|
uint_y = png_get_uint_32(buf + 20);
|
|
int_x_green = (png_fixed_point)uint_x;
|
|
int_y_green = (png_fixed_point)uint_y;
|
|
|
|
uint_x = png_get_uint_32(buf + 24);
|
|
uint_y = png_get_uint_32(buf + 28);
|
|
int_x_blue = (png_fixed_point)uint_x;
|
|
int_y_blue = (png_fixed_point)uint_y;
|
|
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
white_x = (float)int_x_white / (float)100000.0;
|
|
white_y = (float)int_y_white / (float)100000.0;
|
|
red_x = (float)int_x_red / (float)100000.0;
|
|
red_y = (float)int_y_red / (float)100000.0;
|
|
green_x = (float)int_x_green / (float)100000.0;
|
|
green_y = (float)int_y_green / (float)100000.0;
|
|
blue_x = (float)int_x_blue / (float)100000.0;
|
|
blue_y = (float)int_y_blue / (float)100000.0;
|
|
#endif
|
|
|
|
#ifdef PNG_READ_sRGB_SUPPORTED
|
|
if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB))
|
|
{
|
|
if (PNG_OUT_OF_RANGE(int_x_white, 31270, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_y_white, 32900, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_x_red, 64000L, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_y_red, 33000, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_x_green, 30000, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_x_blue, 15000, 1000) ||
|
|
PNG_OUT_OF_RANGE(int_y_blue, 6000, 1000))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring incorrect cHRM value when sRGB is also present");
|
|
#ifdef PNG_CONSOLE_IO_SUPPORTED
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
fprintf(stderr, "wx=%f, wy=%f, rx=%f, ry=%f\n",
|
|
white_x, white_y, red_x, red_y);
|
|
fprintf(stderr, "gx=%f, gy=%f, bx=%f, by=%f\n",
|
|
green_x, green_y, blue_x, blue_y);
|
|
#else
|
|
fprintf(stderr, "wx=%ld, wy=%ld, rx=%ld, ry=%ld\n",
|
|
(long)int_x_white, (long)int_y_white,
|
|
(long)int_x_red, (long)int_y_red);
|
|
fprintf(stderr, "gx=%ld, gy=%ld, bx=%ld, by=%ld\n",
|
|
(long)int_x_green, (long)int_y_green,
|
|
(long)int_x_blue, (long)int_y_blue);
|
|
#endif
|
|
#endif /* PNG_CONSOLE_IO_SUPPORTED */
|
|
}
|
|
return;
|
|
}
|
|
#endif /* PNG_READ_sRGB_SUPPORTED */
|
|
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
png_set_cHRM(png_ptr, info_ptr,
|
|
white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
|
|
#endif
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
png_set_cHRM_fixed(png_ptr, info_ptr,
|
|
int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,
|
|
int_y_green, int_x_blue, int_y_blue);
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_sRGB_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
int intent;
|
|
png_byte buf[1];
|
|
|
|
png_debug(1, "in png_handle_sRGB");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before sRGB");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid sRGB after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (png_ptr->mode & PNG_HAVE_PLTE)
|
|
/* Should be an error, but we can cope with it */
|
|
png_warning(png_ptr, "Out of place sRGB chunk");
|
|
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))
|
|
{
|
|
png_warning(png_ptr, "Duplicate sRGB chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (length != 1)
|
|
{
|
|
png_warning(png_ptr, "Incorrect sRGB chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 1);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
intent = buf[0];
|
|
/* Check for bad intent */
|
|
if (intent >= PNG_sRGB_INTENT_LAST)
|
|
{
|
|
png_warning(png_ptr, "Unknown sRGB intent");
|
|
return;
|
|
}
|
|
|
|
#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA))
|
|
{
|
|
png_fixed_point igamma;
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
igamma=info_ptr->int_gamma;
|
|
#else
|
|
# ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
igamma=(png_fixed_point)(info_ptr->gamma * 100000.);
|
|
# endif
|
|
#endif
|
|
if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring incorrect gAMA value when sRGB is also present");
|
|
#ifdef PNG_CONSOLE_IO_SUPPORTED
|
|
# ifdef PNG_FIXED_POINT_SUPPORTED
|
|
fprintf(stderr, "incorrect gamma=(%d/100000)\n",
|
|
(int)png_ptr->int_gamma);
|
|
# else
|
|
# ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
fprintf(stderr, "incorrect gamma=%f\n", png_ptr->gamma);
|
|
# endif
|
|
# endif
|
|
#endif
|
|
}
|
|
}
|
|
#endif /* PNG_READ_gAMA_SUPPORTED */
|
|
|
|
#ifdef PNG_READ_cHRM_SUPPORTED
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))
|
|
if (PNG_OUT_OF_RANGE(info_ptr->int_x_white, 31270, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_y_white, 32900, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_x_red, 64000L, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_y_red, 33000, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_x_green, 30000, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_y_green, 60000L, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_x_blue, 15000, 1000) ||
|
|
PNG_OUT_OF_RANGE(info_ptr->int_y_blue, 6000, 1000))
|
|
{
|
|
png_warning(png_ptr,
|
|
"Ignoring incorrect cHRM value when sRGB is also present");
|
|
}
|
|
#endif /* PNG_FIXED_POINT_SUPPORTED */
|
|
#endif /* PNG_READ_cHRM_SUPPORTED */
|
|
|
|
png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent);
|
|
}
|
|
#endif /* PNG_READ_sRGB_SUPPORTED */
|
|
|
|
#ifdef PNG_READ_iCCP_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
/* Note: this does not properly handle chunks that are > 64K under DOS */
|
|
{
|
|
png_byte compression_type;
|
|
png_bytep pC;
|
|
png_charp profile;
|
|
png_uint_32 skip = 0;
|
|
png_uint_32 profile_size, profile_length;
|
|
png_size_t slength, prefix_length, data_length;
|
|
|
|
png_debug(1, "in png_handle_iCCP");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before iCCP");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid iCCP after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (png_ptr->mode & PNG_HAVE_PLTE)
|
|
/* Should be an error, but we can cope with it */
|
|
png_warning(png_ptr, "Out of place iCCP chunk");
|
|
|
|
if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP))
|
|
{
|
|
png_warning(png_ptr, "Duplicate iCCP chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
if (length > (png_uint_32)65535L)
|
|
{
|
|
png_warning(png_ptr, "iCCP chunk too large to fit in memory");
|
|
skip = length - (png_uint_32)65535L;
|
|
length = (png_uint_32)65535L;
|
|
}
|
|
#endif
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1);
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
|
|
if (png_crc_finish(png_ptr, skip))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_ptr->chunkdata[slength] = 0x00;
|
|
|
|
for (profile = png_ptr->chunkdata; *profile; profile++)
|
|
/* Empty loop to find end of name */ ;
|
|
|
|
++profile;
|
|
|
|
/* There should be at least one zero (the compression type byte)
|
|
* following the separator, and we should be on it
|
|
*/
|
|
if ( profile >= png_ptr->chunkdata + slength - 1)
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_warning(png_ptr, "Malformed iCCP chunk");
|
|
return;
|
|
}
|
|
|
|
/* Compression_type should always be zero */
|
|
compression_type = *profile++;
|
|
if (compression_type)
|
|
{
|
|
png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk");
|
|
compression_type = 0x00; /* Reset it to zero (libpng-1.0.6 through 1.0.8
|
|
wrote nonzero) */
|
|
}
|
|
|
|
prefix_length = profile - png_ptr->chunkdata;
|
|
png_decompress_chunk(png_ptr, compression_type,
|
|
slength, prefix_length, &data_length);
|
|
|
|
profile_length = data_length - prefix_length;
|
|
|
|
if ( prefix_length > data_length || profile_length < 4)
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_warning(png_ptr, "Profile size field missing from iCCP chunk");
|
|
return;
|
|
}
|
|
|
|
/* Check the profile_size recorded in the first 32 bits of the ICC profile */
|
|
pC = (png_bytep)(png_ptr->chunkdata + prefix_length);
|
|
profile_size = ((*(pC ))<<24) |
|
|
((*(pC + 1))<<16) |
|
|
((*(pC + 2))<< 8) |
|
|
((*(pC + 3)) );
|
|
|
|
if (profile_size < profile_length)
|
|
profile_length = profile_size;
|
|
|
|
if (profile_size > profile_length)
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_warning(png_ptr, "Ignoring truncated iCCP profile.");
|
|
return;
|
|
}
|
|
|
|
png_set_iCCP(png_ptr, info_ptr, png_ptr->chunkdata,
|
|
compression_type, png_ptr->chunkdata + prefix_length, profile_length);
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
}
|
|
#endif /* PNG_READ_iCCP_SUPPORTED */
|
|
|
|
#ifdef PNG_READ_sPLT_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
/* Note: this does not properly handle chunks that are > 64K under DOS */
|
|
{
|
|
png_bytep entry_start;
|
|
png_sPLT_t new_palette;
|
|
#ifdef PNG_POINTER_INDEXING_SUPPORTED
|
|
png_sPLT_entryp pp;
|
|
#endif
|
|
int data_length, entry_size, i;
|
|
png_uint_32 skip = 0;
|
|
png_size_t slength;
|
|
|
|
png_debug(1, "in png_handle_sPLT");
|
|
|
|
#ifdef PNG_USER_LIMITS_SUPPORTED
|
|
|
|
if (png_ptr->user_chunk_cache_max != 0)
|
|
{
|
|
if (png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
if (--png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_warning(png_ptr, "No space in chunk cache for sPLT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before sPLT");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid sPLT after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
if (length > (png_uint_32)65535L)
|
|
{
|
|
png_warning(png_ptr, "sPLT chunk too large to fit in memory");
|
|
skip = length - (png_uint_32)65535L;
|
|
length = (png_uint_32)65535L;
|
|
}
|
|
#endif
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1);
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
|
|
if (png_crc_finish(png_ptr, skip))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_ptr->chunkdata[slength] = 0x00;
|
|
|
|
for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start;
|
|
entry_start++)
|
|
/* Empty loop to find end of name */ ;
|
|
++entry_start;
|
|
|
|
/* A sample depth should follow the separator, and we should be on it */
|
|
if (entry_start > (png_bytep)png_ptr->chunkdata + slength - 2)
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_warning(png_ptr, "malformed sPLT chunk");
|
|
return;
|
|
}
|
|
|
|
new_palette.depth = *entry_start++;
|
|
entry_size = (new_palette.depth == 8 ? 6 : 10);
|
|
data_length = (slength - (entry_start - (png_bytep)png_ptr->chunkdata));
|
|
|
|
/* Integrity-check the data length */
|
|
if (data_length % entry_size)
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_warning(png_ptr, "sPLT chunk has bad length");
|
|
return;
|
|
}
|
|
|
|
new_palette.nentries = (png_int_32) ( data_length / entry_size);
|
|
if ((png_uint_32) new_palette.nentries >
|
|
(png_uint_32) (PNG_SIZE_MAX / png_sizeof(png_sPLT_entry)))
|
|
{
|
|
png_warning(png_ptr, "sPLT chunk too long");
|
|
return;
|
|
}
|
|
new_palette.entries = (png_sPLT_entryp)png_malloc_warn(
|
|
png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry));
|
|
if (new_palette.entries == NULL)
|
|
{
|
|
png_warning(png_ptr, "sPLT chunk requires too much memory");
|
|
return;
|
|
}
|
|
|
|
#ifdef PNG_POINTER_INDEXING_SUPPORTED
|
|
for (i = 0; i < new_palette.nentries; i++)
|
|
{
|
|
pp = new_palette.entries + i;
|
|
|
|
if (new_palette.depth == 8)
|
|
{
|
|
pp->red = *entry_start++;
|
|
pp->green = *entry_start++;
|
|
pp->blue = *entry_start++;
|
|
pp->alpha = *entry_start++;
|
|
}
|
|
else
|
|
{
|
|
pp->red = png_get_uint_16(entry_start); entry_start += 2;
|
|
pp->green = png_get_uint_16(entry_start); entry_start += 2;
|
|
pp->blue = png_get_uint_16(entry_start); entry_start += 2;
|
|
pp->alpha = png_get_uint_16(entry_start); entry_start += 2;
|
|
}
|
|
pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
|
|
}
|
|
#else
|
|
pp = new_palette.entries;
|
|
for (i = 0; i < new_palette.nentries; i++)
|
|
{
|
|
|
|
if (new_palette.depth == 8)
|
|
{
|
|
pp[i].red = *entry_start++;
|
|
pp[i].green = *entry_start++;
|
|
pp[i].blue = *entry_start++;
|
|
pp[i].alpha = *entry_start++;
|
|
}
|
|
else
|
|
{
|
|
pp[i].red = png_get_uint_16(entry_start); entry_start += 2;
|
|
pp[i].green = png_get_uint_16(entry_start); entry_start += 2;
|
|
pp[i].blue = png_get_uint_16(entry_start); entry_start += 2;
|
|
pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2;
|
|
}
|
|
pp->frequency = png_get_uint_16(entry_start); entry_start += 2;
|
|
}
|
|
#endif
|
|
|
|
/* Discard all chunk data except the name and stash that */
|
|
new_palette.name = png_ptr->chunkdata;
|
|
|
|
png_set_sPLT(png_ptr, info_ptr, &new_palette, 1);
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_free(png_ptr, new_palette.entries);
|
|
}
|
|
#endif /* PNG_READ_sPLT_SUPPORTED */
|
|
|
|
#ifdef PNG_READ_tRNS_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_byte readbuf[PNG_MAX_PALETTE_LENGTH];
|
|
|
|
png_debug(1, "in png_handle_tRNS");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before tRNS");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid tRNS after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))
|
|
{
|
|
png_warning(png_ptr, "Duplicate tRNS chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
|
|
{
|
|
png_byte buf[2];
|
|
|
|
if (length != 2)
|
|
{
|
|
png_warning(png_ptr, "Incorrect tRNS chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 2);
|
|
png_ptr->num_trans = 1;
|
|
png_ptr->trans_values.gray = png_get_uint_16(buf);
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
|
|
{
|
|
png_byte buf[6];
|
|
|
|
if (length != 6)
|
|
{
|
|
png_warning(png_ptr, "Incorrect tRNS chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
png_crc_read(png_ptr, buf, (png_size_t)length);
|
|
png_ptr->num_trans = 1;
|
|
png_ptr->trans_values.red = png_get_uint_16(buf);
|
|
png_ptr->trans_values.green = png_get_uint_16(buf + 2);
|
|
png_ptr->trans_values.blue = png_get_uint_16(buf + 4);
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
if (!(png_ptr->mode & PNG_HAVE_PLTE))
|
|
{
|
|
/* Should be an error, but we can cope with it. */
|
|
png_warning(png_ptr, "Missing PLTE before tRNS");
|
|
}
|
|
if (length > (png_uint_32)png_ptr->num_palette ||
|
|
length > PNG_MAX_PALETTE_LENGTH)
|
|
{
|
|
png_warning(png_ptr, "Incorrect tRNS chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
if (length == 0)
|
|
{
|
|
png_warning(png_ptr, "Zero length tRNS chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
png_crc_read(png_ptr, readbuf, (png_size_t)length);
|
|
png_ptr->num_trans = (png_uint_16)length;
|
|
}
|
|
else
|
|
{
|
|
png_warning(png_ptr, "tRNS chunk not allowed with alpha channel");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (png_crc_finish(png_ptr, 0))
|
|
{
|
|
png_ptr->num_trans = 0;
|
|
return;
|
|
}
|
|
|
|
png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,
|
|
&(png_ptr->trans_values));
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_bKGD_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_size_t truelen;
|
|
png_byte buf[6];
|
|
|
|
png_debug(1, "in png_handle_bKGD");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before bKGD");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid bKGD after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&
|
|
!(png_ptr->mode & PNG_HAVE_PLTE))
|
|
{
|
|
png_warning(png_ptr, "Missing PLTE before bKGD");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD))
|
|
{
|
|
png_warning(png_ptr, "Duplicate bKGD chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
truelen = 1;
|
|
else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)
|
|
truelen = 6;
|
|
else
|
|
truelen = 2;
|
|
|
|
if (length != truelen)
|
|
{
|
|
png_warning(png_ptr, "Incorrect bKGD chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, truelen);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
/* We convert the index value into RGB components so that we can allow
|
|
* arbitrary RGB values for background when we have transparency, and
|
|
* so it is easy to determine the RGB values of the background color
|
|
* from the info_ptr struct. */
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
png_ptr->background.index = buf[0];
|
|
if (info_ptr && info_ptr->num_palette)
|
|
{
|
|
if (buf[0] >= info_ptr->num_palette)
|
|
{
|
|
png_warning(png_ptr, "Incorrect bKGD chunk index value");
|
|
return;
|
|
}
|
|
png_ptr->background.red =
|
|
(png_uint_16)png_ptr->palette[buf[0]].red;
|
|
png_ptr->background.green =
|
|
(png_uint_16)png_ptr->palette[buf[0]].green;
|
|
png_ptr->background.blue =
|
|
(png_uint_16)png_ptr->palette[buf[0]].blue;
|
|
}
|
|
}
|
|
else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */
|
|
{
|
|
png_ptr->background.red =
|
|
png_ptr->background.green =
|
|
png_ptr->background.blue =
|
|
png_ptr->background.gray = png_get_uint_16(buf);
|
|
}
|
|
else
|
|
{
|
|
png_ptr->background.red = png_get_uint_16(buf);
|
|
png_ptr->background.green = png_get_uint_16(buf + 2);
|
|
png_ptr->background.blue = png_get_uint_16(buf + 4);
|
|
}
|
|
|
|
png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background));
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_hIST_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
unsigned int num, i;
|
|
png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH];
|
|
|
|
png_debug(1, "in png_handle_hIST");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before hIST");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid hIST after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (!(png_ptr->mode & PNG_HAVE_PLTE))
|
|
{
|
|
png_warning(png_ptr, "Missing PLTE before hIST");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST))
|
|
{
|
|
png_warning(png_ptr, "Duplicate hIST chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
num = length / 2 ;
|
|
if (num != (unsigned int) png_ptr->num_palette || num >
|
|
(unsigned int) PNG_MAX_PALETTE_LENGTH)
|
|
{
|
|
png_warning(png_ptr, "Incorrect hIST chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
for (i = 0; i < num; i++)
|
|
{
|
|
png_byte buf[2];
|
|
|
|
png_crc_read(png_ptr, buf, 2);
|
|
readbuf[i] = png_get_uint_16(buf);
|
|
}
|
|
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
png_set_hIST(png_ptr, info_ptr, readbuf);
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_pHYs_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_byte buf[9];
|
|
png_uint_32 res_x, res_y;
|
|
int unit_type;
|
|
|
|
png_debug(1, "in png_handle_pHYs");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before pHYs");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid pHYs after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))
|
|
{
|
|
png_warning(png_ptr, "Duplicate pHYs chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (length != 9)
|
|
{
|
|
png_warning(png_ptr, "Incorrect pHYs chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 9);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
res_x = png_get_uint_32(buf);
|
|
res_y = png_get_uint_32(buf + 4);
|
|
unit_type = buf[8];
|
|
png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type);
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_oFFs_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_byte buf[9];
|
|
png_int_32 offset_x, offset_y;
|
|
int unit_type;
|
|
|
|
png_debug(1, "in png_handle_oFFs");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before oFFs");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid oFFs after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))
|
|
{
|
|
png_warning(png_ptr, "Duplicate oFFs chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (length != 9)
|
|
{
|
|
png_warning(png_ptr, "Incorrect oFFs chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 9);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
offset_x = png_get_int_32(buf);
|
|
offset_y = png_get_int_32(buf + 4);
|
|
unit_type = buf[8];
|
|
png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type);
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_pCAL_SUPPORTED
|
|
/* Read the pCAL chunk (described in the PNG Extensions document) */
|
|
void /* PRIVATE */
|
|
png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_int_32 X0, X1;
|
|
png_byte type, nparams;
|
|
png_charp buf, units, endptr;
|
|
png_charpp params;
|
|
png_size_t slength;
|
|
int i;
|
|
|
|
png_debug(1, "in png_handle_pCAL");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before pCAL");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid pCAL after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL))
|
|
{
|
|
png_warning(png_ptr, "Duplicate pCAL chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_debug1(2, "Allocating and reading pCAL chunk data (%lu bytes)",
|
|
length + 1);
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
|
|
if (png_ptr->chunkdata == NULL)
|
|
{
|
|
png_warning(png_ptr, "No memory for pCAL purpose.");
|
|
return;
|
|
}
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
|
|
if (png_crc_finish(png_ptr, 0))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_ptr->chunkdata[slength] = 0x00; /* Null terminate the last string */
|
|
|
|
png_debug(3, "Finding end of pCAL purpose string");
|
|
for (buf = png_ptr->chunkdata; *buf; buf++)
|
|
/* Empty loop */ ;
|
|
|
|
endptr = png_ptr->chunkdata + slength;
|
|
|
|
/* We need to have at least 12 bytes after the purpose string
|
|
in order to get the parameter information. */
|
|
if (endptr <= buf + 12)
|
|
{
|
|
png_warning(png_ptr, "Invalid pCAL data");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_debug(3, "Reading pCAL X0, X1, type, nparams, and units");
|
|
X0 = png_get_int_32((png_bytep)buf+1);
|
|
X1 = png_get_int_32((png_bytep)buf+5);
|
|
type = buf[9];
|
|
nparams = buf[10];
|
|
units = buf + 11;
|
|
|
|
png_debug(3, "Checking pCAL equation type and number of parameters");
|
|
/* Check that we have the right number of parameters for known
|
|
equation types. */
|
|
if ((type == PNG_EQUATION_LINEAR && nparams != 2) ||
|
|
(type == PNG_EQUATION_BASE_E && nparams != 3) ||
|
|
(type == PNG_EQUATION_ARBITRARY && nparams != 3) ||
|
|
(type == PNG_EQUATION_HYPERBOLIC && nparams != 4))
|
|
{
|
|
png_warning(png_ptr, "Invalid pCAL parameters for equation type");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
else if (type >= PNG_EQUATION_LAST)
|
|
{
|
|
png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");
|
|
}
|
|
|
|
for (buf = units; *buf; buf++)
|
|
/* Empty loop to move past the units string. */ ;
|
|
|
|
png_debug(3, "Allocating pCAL parameters array");
|
|
params = (png_charpp)png_malloc_warn(png_ptr,
|
|
(png_uint_32)(nparams * png_sizeof(png_charp))) ;
|
|
if (params == NULL)
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_warning(png_ptr, "No memory for pCAL params.");
|
|
return;
|
|
}
|
|
|
|
/* Get pointers to the start of each parameter string. */
|
|
for (i = 0; i < (int)nparams; i++)
|
|
{
|
|
buf++; /* Skip the null string terminator from previous parameter. */
|
|
|
|
png_debug1(3, "Reading pCAL parameter %d", i);
|
|
for (params[i] = buf; buf <= endptr && *buf != 0x00; buf++)
|
|
/* Empty loop to move past each parameter string */ ;
|
|
|
|
/* Make sure we haven't run out of data yet */
|
|
if (buf > endptr)
|
|
{
|
|
png_warning(png_ptr, "Invalid pCAL data");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_free(png_ptr, params);
|
|
return;
|
|
}
|
|
}
|
|
|
|
png_set_pCAL(png_ptr, info_ptr, png_ptr->chunkdata, X0, X1, type, nparams,
|
|
units, params);
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_free(png_ptr, params);
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_sCAL_SUPPORTED
|
|
/* Read the sCAL chunk */
|
|
void /* PRIVATE */
|
|
png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_charp ep;
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
double width, height;
|
|
png_charp vp;
|
|
#else
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
png_charp swidth, sheight;
|
|
#endif
|
|
#endif
|
|
png_size_t slength;
|
|
|
|
png_debug(1, "in png_handle_sCAL");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before sCAL");
|
|
else if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
png_warning(png_ptr, "Invalid sCAL after IDAT");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL))
|
|
{
|
|
png_warning(png_ptr, "Duplicate sCAL chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
/* Need unit type, width, \0, height: minimum 4 bytes */
|
|
else if (length < 4)
|
|
{
|
|
png_warning(png_ptr, "sCAL chunk too short");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_debug1(2, "Allocating and reading sCAL chunk data (%lu bytes)",
|
|
length + 1);
|
|
png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
|
|
if (png_ptr->chunkdata == NULL)
|
|
{
|
|
png_warning(png_ptr, "Out of memory while processing sCAL chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
|
|
if (png_crc_finish(png_ptr, 0))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_ptr->chunkdata[slength] = 0x00; /* Null terminate the last string */
|
|
|
|
ep = png_ptr->chunkdata + 1; /* Skip unit byte */
|
|
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
width = png_strtod(png_ptr, ep, &vp);
|
|
if (*vp)
|
|
{
|
|
png_warning(png_ptr, "malformed width string in sCAL chunk");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
#else
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
swidth = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);
|
|
if (swidth == NULL)
|
|
{
|
|
png_warning(png_ptr, "Out of memory while processing sCAL chunk width");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
png_memcpy(swidth, ep, (png_size_t)png_strlen(ep));
|
|
#endif
|
|
#endif
|
|
|
|
for (ep = png_ptr->chunkdata; *ep; ep++)
|
|
/* Empty loop */ ;
|
|
ep++;
|
|
|
|
if (png_ptr->chunkdata + slength < ep)
|
|
{
|
|
png_warning(png_ptr, "Truncated sCAL chunk");
|
|
#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
|
|
png_free(png_ptr, swidth);
|
|
#endif
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
height = png_strtod(png_ptr, ep, &vp);
|
|
if (*vp)
|
|
{
|
|
png_warning(png_ptr, "malformed height string in sCAL chunk");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
|
|
png_free(png_ptr, swidth);
|
|
#endif
|
|
return;
|
|
}
|
|
#else
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
sheight = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);
|
|
if (sheight == NULL)
|
|
{
|
|
png_warning(png_ptr, "Out of memory while processing sCAL chunk height");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
|
|
png_free(png_ptr, swidth);
|
|
#endif
|
|
return;
|
|
}
|
|
png_memcpy(sheight, ep, (png_size_t)png_strlen(ep));
|
|
#endif
|
|
#endif
|
|
|
|
if (png_ptr->chunkdata + slength < ep
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
|| width <= 0. || height <= 0.
|
|
#endif
|
|
)
|
|
{
|
|
png_warning(png_ptr, "Invalid sCAL data");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
|
|
png_free(png_ptr, swidth);
|
|
png_free(png_ptr, sheight);
|
|
#endif
|
|
return;
|
|
}
|
|
|
|
|
|
#ifdef PNG_FLOATING_POINT_SUPPORTED
|
|
png_set_sCAL(png_ptr, info_ptr, png_ptr->chunkdata[0], width, height);
|
|
#else
|
|
#ifdef PNG_FIXED_POINT_SUPPORTED
|
|
png_set_sCAL_s(png_ptr, info_ptr, png_ptr->chunkdata[0], swidth, sheight);
|
|
#endif
|
|
#endif
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)
|
|
png_free(png_ptr, swidth);
|
|
png_free(png_ptr, sheight);
|
|
#endif
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_tIME_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_byte buf[7];
|
|
png_time mod_time;
|
|
|
|
png_debug(1, "in png_handle_tIME");
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Out of place tIME chunk");
|
|
else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME))
|
|
{
|
|
png_warning(png_ptr, "Duplicate tIME chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
|
|
if (length != 7)
|
|
{
|
|
png_warning(png_ptr, "Incorrect tIME chunk length");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
|
|
png_crc_read(png_ptr, buf, 7);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
return;
|
|
|
|
mod_time.second = buf[6];
|
|
mod_time.minute = buf[5];
|
|
mod_time.hour = buf[4];
|
|
mod_time.day = buf[3];
|
|
mod_time.month = buf[2];
|
|
mod_time.year = png_get_uint_16(buf);
|
|
|
|
png_set_tIME(png_ptr, info_ptr, &mod_time);
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_tEXt_SUPPORTED
|
|
/* Note: this does not properly handle chunks that are > 64K under DOS */
|
|
void /* PRIVATE */
|
|
png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_textp text_ptr;
|
|
png_charp key;
|
|
png_charp text;
|
|
png_uint_32 skip = 0;
|
|
png_size_t slength;
|
|
int ret;
|
|
|
|
png_debug(1, "in png_handle_tEXt");
|
|
|
|
#ifdef PNG_USER_LIMITS_SUPPORTED
|
|
if (png_ptr->user_chunk_cache_max != 0)
|
|
{
|
|
if (png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
if (--png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_warning(png_ptr, "No space in chunk cache for tEXt");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before tEXt");
|
|
|
|
if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
if (length > (png_uint_32)65535L)
|
|
{
|
|
png_warning(png_ptr, "tEXt chunk too large to fit in memory");
|
|
skip = length - (png_uint_32)65535L;
|
|
length = (png_uint_32)65535L;
|
|
}
|
|
#endif
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
|
|
png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
|
|
if (png_ptr->chunkdata == NULL)
|
|
{
|
|
png_warning(png_ptr, "No memory to process text chunk.");
|
|
return;
|
|
}
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
|
|
if (png_crc_finish(png_ptr, skip))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
key = png_ptr->chunkdata;
|
|
|
|
key[slength] = 0x00;
|
|
|
|
for (text = key; *text; text++)
|
|
/* Empty loop to find end of key */ ;
|
|
|
|
if (text != key + slength)
|
|
text++;
|
|
|
|
text_ptr = (png_textp)png_malloc_warn(png_ptr,
|
|
(png_uint_32)png_sizeof(png_text));
|
|
if (text_ptr == NULL)
|
|
{
|
|
png_warning(png_ptr, "Not enough memory to process text chunk.");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;
|
|
text_ptr->key = key;
|
|
#ifdef PNG_iTXt_SUPPORTED
|
|
text_ptr->lang = NULL;
|
|
text_ptr->lang_key = NULL;
|
|
text_ptr->itxt_length = 0;
|
|
#endif
|
|
text_ptr->text = text;
|
|
text_ptr->text_length = png_strlen(text);
|
|
|
|
ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
png_free(png_ptr, text_ptr);
|
|
if (ret)
|
|
png_warning(png_ptr, "Insufficient memory to process text chunk.");
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_zTXt_SUPPORTED
|
|
/* Note: this does not correctly handle chunks that are > 64K under DOS */
|
|
void /* PRIVATE */
|
|
png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_textp text_ptr;
|
|
png_charp text;
|
|
int comp_type;
|
|
int ret;
|
|
png_size_t slength, prefix_len, data_len;
|
|
|
|
png_debug(1, "in png_handle_zTXt");
|
|
|
|
#ifdef PNG_USER_LIMITS_SUPPORTED
|
|
if (png_ptr->user_chunk_cache_max != 0)
|
|
{
|
|
if (png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
if (--png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_warning(png_ptr, "No space in chunk cache for zTXt");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before zTXt");
|
|
|
|
if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
/* We will no doubt have problems with chunks even half this size, but
|
|
there is no hard and fast rule to tell us where to stop. */
|
|
if (length > (png_uint_32)65535L)
|
|
{
|
|
png_warning(png_ptr, "zTXt chunk too large to fit in memory");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
|
|
if (png_ptr->chunkdata == NULL)
|
|
{
|
|
png_warning(png_ptr, "Out of memory processing zTXt chunk.");
|
|
return;
|
|
}
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_ptr->chunkdata[slength] = 0x00;
|
|
|
|
for (text = png_ptr->chunkdata; *text; text++)
|
|
/* Empty loop */ ;
|
|
|
|
/* zTXt must have some text after the chunkdataword */
|
|
if (text >= png_ptr->chunkdata + slength - 2)
|
|
{
|
|
png_warning(png_ptr, "Truncated zTXt chunk");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
else
|
|
{
|
|
comp_type = *(++text);
|
|
if (comp_type != PNG_TEXT_COMPRESSION_zTXt)
|
|
{
|
|
png_warning(png_ptr, "Unknown compression type in zTXt chunk");
|
|
comp_type = PNG_TEXT_COMPRESSION_zTXt;
|
|
}
|
|
text++; /* Skip the compression_method byte */
|
|
}
|
|
prefix_len = text - png_ptr->chunkdata;
|
|
|
|
png_decompress_chunk(png_ptr, comp_type,
|
|
(png_size_t)length, prefix_len, &data_len);
|
|
|
|
text_ptr = (png_textp)png_malloc_warn(png_ptr,
|
|
(png_uint_32)png_sizeof(png_text));
|
|
if (text_ptr == NULL)
|
|
{
|
|
png_warning(png_ptr, "Not enough memory to process zTXt chunk.");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
text_ptr->compression = comp_type;
|
|
text_ptr->key = png_ptr->chunkdata;
|
|
#ifdef PNG_iTXt_SUPPORTED
|
|
text_ptr->lang = NULL;
|
|
text_ptr->lang_key = NULL;
|
|
text_ptr->itxt_length = 0;
|
|
#endif
|
|
text_ptr->text = png_ptr->chunkdata + prefix_len;
|
|
text_ptr->text_length = data_len;
|
|
|
|
ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
|
|
|
|
png_free(png_ptr, text_ptr);
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
if (ret)
|
|
png_error(png_ptr, "Insufficient memory to store zTXt chunk.");
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_iTXt_SUPPORTED
|
|
/* Note: this does not correctly handle chunks that are > 64K under DOS */
|
|
void /* PRIVATE */
|
|
png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_textp text_ptr;
|
|
png_charp key, lang, text, lang_key;
|
|
int comp_flag;
|
|
int comp_type = 0;
|
|
int ret;
|
|
png_size_t slength, prefix_len, data_len;
|
|
|
|
png_debug(1, "in png_handle_iTXt");
|
|
|
|
#ifdef PNG_USER_LIMITS_SUPPORTED
|
|
if (png_ptr->user_chunk_cache_max != 0)
|
|
{
|
|
if (png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
if (--png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_warning(png_ptr, "No space in chunk cache for iTXt");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (!(png_ptr->mode & PNG_HAVE_IHDR))
|
|
png_error(png_ptr, "Missing IHDR before iTXt");
|
|
|
|
if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
/* We will no doubt have problems with chunks even half this size, but
|
|
there is no hard and fast rule to tell us where to stop. */
|
|
if (length > (png_uint_32)65535L)
|
|
{
|
|
png_warning(png_ptr, "iTXt chunk too large to fit in memory");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);
|
|
if (png_ptr->chunkdata == NULL)
|
|
{
|
|
png_warning(png_ptr, "No memory to process iTXt chunk.");
|
|
return;
|
|
}
|
|
slength = (png_size_t)length;
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);
|
|
if (png_crc_finish(png_ptr, 0))
|
|
{
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
png_ptr->chunkdata[slength] = 0x00;
|
|
|
|
for (lang = png_ptr->chunkdata; *lang; lang++)
|
|
/* Empty loop */ ;
|
|
lang++; /* Skip NUL separator */
|
|
|
|
/* iTXt must have a language tag (possibly empty), two compression bytes,
|
|
* translated keyword (possibly empty), and possibly some text after the
|
|
* keyword
|
|
*/
|
|
|
|
if (lang >= png_ptr->chunkdata + slength - 3)
|
|
{
|
|
png_warning(png_ptr, "Truncated iTXt chunk");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
else
|
|
{
|
|
comp_flag = *lang++;
|
|
comp_type = *lang++;
|
|
}
|
|
|
|
for (lang_key = lang; *lang_key; lang_key++)
|
|
/* Empty loop */ ;
|
|
lang_key++; /* Skip NUL separator */
|
|
|
|
if (lang_key >= png_ptr->chunkdata + slength)
|
|
{
|
|
png_warning(png_ptr, "Truncated iTXt chunk");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
for (text = lang_key; *text; text++)
|
|
/* Empty loop */ ;
|
|
text++; /* Skip NUL separator */
|
|
if (text >= png_ptr->chunkdata + slength)
|
|
{
|
|
png_warning(png_ptr, "Malformed iTXt chunk");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
|
|
prefix_len = text - png_ptr->chunkdata;
|
|
|
|
key=png_ptr->chunkdata;
|
|
if (comp_flag)
|
|
png_decompress_chunk(png_ptr, comp_type,
|
|
(size_t)length, prefix_len, &data_len);
|
|
else
|
|
data_len = png_strlen(png_ptr->chunkdata + prefix_len);
|
|
text_ptr = (png_textp)png_malloc_warn(png_ptr,
|
|
(png_uint_32)png_sizeof(png_text));
|
|
if (text_ptr == NULL)
|
|
{
|
|
png_warning(png_ptr, "Not enough memory to process iTXt chunk.");
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
return;
|
|
}
|
|
text_ptr->compression = (int)comp_flag + 1;
|
|
text_ptr->lang_key = png_ptr->chunkdata + (lang_key - key);
|
|
text_ptr->lang = png_ptr->chunkdata + (lang - key);
|
|
text_ptr->itxt_length = data_len;
|
|
text_ptr->text_length = 0;
|
|
text_ptr->key = png_ptr->chunkdata;
|
|
text_ptr->text = png_ptr->chunkdata + prefix_len;
|
|
|
|
ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);
|
|
|
|
png_free(png_ptr, text_ptr);
|
|
png_free(png_ptr, png_ptr->chunkdata);
|
|
png_ptr->chunkdata = NULL;
|
|
if (ret)
|
|
png_error(png_ptr, "Insufficient memory to store iTXt chunk.");
|
|
}
|
|
#endif
|
|
|
|
/* This function is called when we haven't found a handler for a
|
|
chunk. If there isn't a problem with the chunk itself (ie bad
|
|
chunk name, CRC, or a critical chunk), the chunk is silently ignored
|
|
-- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which
|
|
case it will be saved away to be written out later. */
|
|
void /* PRIVATE */
|
|
png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
|
|
{
|
|
png_uint_32 skip = 0;
|
|
|
|
png_debug(1, "in png_handle_unknown");
|
|
|
|
#ifdef PNG_USER_LIMITS_SUPPORTED
|
|
if (png_ptr->user_chunk_cache_max != 0)
|
|
{
|
|
if (png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
if (--png_ptr->user_chunk_cache_max == 1)
|
|
{
|
|
png_warning(png_ptr, "No space in chunk cache for unknown chunk");
|
|
png_crc_finish(png_ptr, length);
|
|
return;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (png_ptr->mode & PNG_HAVE_IDAT)
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_CONST PNG_IDAT;
|
|
#endif
|
|
if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) /* Not an IDAT */
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
}
|
|
|
|
if (!(png_ptr->chunk_name[0] & 0x20))
|
|
{
|
|
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
|
|
if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
|
|
PNG_HANDLE_CHUNK_ALWAYS
|
|
#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
|
|
&& png_ptr->read_user_chunk_fn == NULL
|
|
#endif
|
|
)
|
|
#endif
|
|
png_chunk_error(png_ptr, "unknown critical chunk");
|
|
}
|
|
|
|
#ifdef PNG_READ_UNKNOWN_CHUNKS_SUPPORTED
|
|
if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS)
|
|
#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
|
|
|| (png_ptr->read_user_chunk_fn != NULL)
|
|
#endif
|
|
)
|
|
{
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
if (length > (png_uint_32)65535L)
|
|
{
|
|
png_warning(png_ptr, "unknown chunk too large to fit in memory");
|
|
skip = length - (png_uint_32)65535L;
|
|
length = (png_uint_32)65535L;
|
|
}
|
|
#endif
|
|
png_memcpy((png_charp)png_ptr->unknown_chunk.name,
|
|
(png_charp)png_ptr->chunk_name,
|
|
png_sizeof(png_ptr->unknown_chunk.name));
|
|
png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name)-1]
|
|
= '\0';
|
|
png_ptr->unknown_chunk.size = (png_size_t)length;
|
|
if (length == 0)
|
|
png_ptr->unknown_chunk.data = NULL;
|
|
else
|
|
{
|
|
png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);
|
|
png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);
|
|
}
|
|
#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
|
|
if (png_ptr->read_user_chunk_fn != NULL)
|
|
{
|
|
/* Callback to user unknown chunk handler */
|
|
int ret;
|
|
ret = (*(png_ptr->read_user_chunk_fn))
|
|
(png_ptr, &png_ptr->unknown_chunk);
|
|
if (ret < 0)
|
|
png_chunk_error(png_ptr, "error in user chunk");
|
|
if (ret == 0)
|
|
{
|
|
if (!(png_ptr->chunk_name[0] & 0x20))
|
|
#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
|
|
if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=
|
|
PNG_HANDLE_CHUNK_ALWAYS)
|
|
#endif
|
|
png_chunk_error(png_ptr, "unknown critical chunk");
|
|
png_set_unknown_chunks(png_ptr, info_ptr,
|
|
&png_ptr->unknown_chunk, 1);
|
|
}
|
|
}
|
|
else
|
|
#endif
|
|
png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);
|
|
png_free(png_ptr, png_ptr->unknown_chunk.data);
|
|
png_ptr->unknown_chunk.data = NULL;
|
|
}
|
|
else
|
|
#endif
|
|
skip = length;
|
|
|
|
png_crc_finish(png_ptr, skip);
|
|
|
|
#ifndef PNG_READ_USER_CHUNKS_SUPPORTED
|
|
info_ptr = info_ptr; /* Quiet compiler warnings about unused info_ptr */
|
|
#endif
|
|
}
|
|
|
|
/* This function is called to verify that a chunk name is valid.
|
|
This function can't have the "critical chunk check" incorporated
|
|
into it, since in the future we will need to be able to call user
|
|
functions to handle unknown critical chunks after we check that
|
|
the chunk name itself is valid. */
|
|
|
|
#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))
|
|
|
|
void /* PRIVATE */
|
|
png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name)
|
|
{
|
|
png_debug(1, "in png_check_chunk_name");
|
|
if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) ||
|
|
isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3]))
|
|
{
|
|
png_chunk_error(png_ptr, "invalid chunk type");
|
|
}
|
|
}
|
|
|
|
/* Combines the row recently read in with the existing pixels in the
|
|
row. This routine takes care of alpha and transparency if requested.
|
|
This routine also handles the two methods of progressive display
|
|
of interlaced images, depending on the mask value.
|
|
The mask value describes which pixels are to be combined with
|
|
the row. The pattern always repeats every 8 pixels, so just 8
|
|
bits are needed. A one indicates the pixel is to be combined,
|
|
a zero indicates the pixel is to be skipped. This is in addition
|
|
to any alpha or transparency value associated with the pixel. If
|
|
you want all pixels to be combined, pass 0xff (255) in mask. */
|
|
|
|
void /* PRIVATE */
|
|
png_combine_row(png_structp png_ptr, png_bytep row, int mask)
|
|
{
|
|
png_debug(1, "in png_combine_row");
|
|
if (mask == 0xff)
|
|
{
|
|
png_memcpy(row, png_ptr->row_buf + 1,
|
|
PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width));
|
|
}
|
|
else
|
|
{
|
|
switch (png_ptr->row_info.pixel_depth)
|
|
{
|
|
case 1:
|
|
{
|
|
png_bytep sp = png_ptr->row_buf + 1;
|
|
png_bytep dp = row;
|
|
int s_inc, s_start, s_end;
|
|
int m = 0x80;
|
|
int shift;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = png_ptr->width;
|
|
|
|
#ifdef PNG_READ_PACKSWAP_SUPPORTED
|
|
if (png_ptr->transformations & PNG_PACKSWAP)
|
|
{
|
|
s_start = 0;
|
|
s_end = 7;
|
|
s_inc = 1;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
s_start = 7;
|
|
s_end = 0;
|
|
s_inc = -1;
|
|
}
|
|
|
|
shift = s_start;
|
|
|
|
for (i = 0; i < row_width; i++)
|
|
{
|
|
if (m & mask)
|
|
{
|
|
int value;
|
|
|
|
value = (*sp >> shift) & 0x01;
|
|
*dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);
|
|
*dp |= (png_byte)(value << shift);
|
|
}
|
|
|
|
if (shift == s_end)
|
|
{
|
|
shift = s_start;
|
|
sp++;
|
|
dp++;
|
|
}
|
|
else
|
|
shift += s_inc;
|
|
|
|
if (m == 1)
|
|
m = 0x80;
|
|
else
|
|
m >>= 1;
|
|
}
|
|
break;
|
|
}
|
|
case 2:
|
|
{
|
|
png_bytep sp = png_ptr->row_buf + 1;
|
|
png_bytep dp = row;
|
|
int s_start, s_end, s_inc;
|
|
int m = 0x80;
|
|
int shift;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = png_ptr->width;
|
|
int value;
|
|
|
|
#ifdef PNG_READ_PACKSWAP_SUPPORTED
|
|
if (png_ptr->transformations & PNG_PACKSWAP)
|
|
{
|
|
s_start = 0;
|
|
s_end = 6;
|
|
s_inc = 2;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
s_start = 6;
|
|
s_end = 0;
|
|
s_inc = -2;
|
|
}
|
|
|
|
shift = s_start;
|
|
|
|
for (i = 0; i < row_width; i++)
|
|
{
|
|
if (m & mask)
|
|
{
|
|
value = (*sp >> shift) & 0x03;
|
|
*dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);
|
|
*dp |= (png_byte)(value << shift);
|
|
}
|
|
|
|
if (shift == s_end)
|
|
{
|
|
shift = s_start;
|
|
sp++;
|
|
dp++;
|
|
}
|
|
else
|
|
shift += s_inc;
|
|
if (m == 1)
|
|
m = 0x80;
|
|
else
|
|
m >>= 1;
|
|
}
|
|
break;
|
|
}
|
|
case 4:
|
|
{
|
|
png_bytep sp = png_ptr->row_buf + 1;
|
|
png_bytep dp = row;
|
|
int s_start, s_end, s_inc;
|
|
int m = 0x80;
|
|
int shift;
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = png_ptr->width;
|
|
int value;
|
|
|
|
#ifdef PNG_READ_PACKSWAP_SUPPORTED
|
|
if (png_ptr->transformations & PNG_PACKSWAP)
|
|
{
|
|
s_start = 0;
|
|
s_end = 4;
|
|
s_inc = 4;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
s_start = 4;
|
|
s_end = 0;
|
|
s_inc = -4;
|
|
}
|
|
shift = s_start;
|
|
|
|
for (i = 0; i < row_width; i++)
|
|
{
|
|
if (m & mask)
|
|
{
|
|
value = (*sp >> shift) & 0xf;
|
|
*dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);
|
|
*dp |= (png_byte)(value << shift);
|
|
}
|
|
|
|
if (shift == s_end)
|
|
{
|
|
shift = s_start;
|
|
sp++;
|
|
dp++;
|
|
}
|
|
else
|
|
shift += s_inc;
|
|
if (m == 1)
|
|
m = 0x80;
|
|
else
|
|
m >>= 1;
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
{
|
|
png_bytep sp = png_ptr->row_buf + 1;
|
|
png_bytep dp = row;
|
|
png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);
|
|
png_uint_32 i;
|
|
png_uint_32 row_width = png_ptr->width;
|
|
png_byte m = 0x80;
|
|
|
|
|
|
for (i = 0; i < row_width; i++)
|
|
{
|
|
if (m & mask)
|
|
{
|
|
png_memcpy(dp, sp, pixel_bytes);
|
|
}
|
|
|
|
sp += pixel_bytes;
|
|
dp += pixel_bytes;
|
|
|
|
if (m == 1)
|
|
m = 0x80;
|
|
else
|
|
m >>= 1;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#ifdef PNG_READ_INTERLACING_SUPPORTED
|
|
/* OLD pre-1.0.9 interface:
|
|
void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,
|
|
png_uint_32 transformations)
|
|
*/
|
|
void /* PRIVATE */
|
|
png_do_read_interlace(png_structp png_ptr)
|
|
{
|
|
png_row_infop row_info = &(png_ptr->row_info);
|
|
png_bytep row = png_ptr->row_buf + 1;
|
|
int pass = png_ptr->pass;
|
|
png_uint_32 transformations = png_ptr->transformations;
|
|
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
/* Offset to next interlace block */
|
|
PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
|
|
png_debug(1, "in png_do_read_interlace");
|
|
if (row != NULL && row_info != NULL)
|
|
{
|
|
png_uint_32 final_width;
|
|
|
|
final_width = row_info->width * png_pass_inc[pass];
|
|
|
|
switch (row_info->pixel_depth)
|
|
{
|
|
case 1:
|
|
{
|
|
png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);
|
|
png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);
|
|
int sshift, dshift;
|
|
int s_start, s_end, s_inc;
|
|
int jstop = png_pass_inc[pass];
|
|
png_byte v;
|
|
png_uint_32 i;
|
|
int j;
|
|
|
|
#ifdef PNG_READ_PACKSWAP_SUPPORTED
|
|
if (transformations & PNG_PACKSWAP)
|
|
{
|
|
sshift = (int)((row_info->width + 7) & 0x07);
|
|
dshift = (int)((final_width + 7) & 0x07);
|
|
s_start = 7;
|
|
s_end = 0;
|
|
s_inc = -1;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
sshift = 7 - (int)((row_info->width + 7) & 0x07);
|
|
dshift = 7 - (int)((final_width + 7) & 0x07);
|
|
s_start = 0;
|
|
s_end = 7;
|
|
s_inc = 1;
|
|
}
|
|
|
|
for (i = 0; i < row_info->width; i++)
|
|
{
|
|
v = (png_byte)((*sp >> sshift) & 0x01);
|
|
for (j = 0; j < jstop; j++)
|
|
{
|
|
*dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);
|
|
*dp |= (png_byte)(v << dshift);
|
|
if (dshift == s_end)
|
|
{
|
|
dshift = s_start;
|
|
dp--;
|
|
}
|
|
else
|
|
dshift += s_inc;
|
|
}
|
|
if (sshift == s_end)
|
|
{
|
|
sshift = s_start;
|
|
sp--;
|
|
}
|
|
else
|
|
sshift += s_inc;
|
|
}
|
|
break;
|
|
}
|
|
case 2:
|
|
{
|
|
png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);
|
|
png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);
|
|
int sshift, dshift;
|
|
int s_start, s_end, s_inc;
|
|
int jstop = png_pass_inc[pass];
|
|
png_uint_32 i;
|
|
|
|
#ifdef PNG_READ_PACKSWAP_SUPPORTED
|
|
if (transformations & PNG_PACKSWAP)
|
|
{
|
|
sshift = (int)(((row_info->width + 3) & 0x03) << 1);
|
|
dshift = (int)(((final_width + 3) & 0x03) << 1);
|
|
s_start = 6;
|
|
s_end = 0;
|
|
s_inc = -2;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1);
|
|
dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1);
|
|
s_start = 0;
|
|
s_end = 6;
|
|
s_inc = 2;
|
|
}
|
|
|
|
for (i = 0; i < row_info->width; i++)
|
|
{
|
|
png_byte v;
|
|
int j;
|
|
|
|
v = (png_byte)((*sp >> sshift) & 0x03);
|
|
for (j = 0; j < jstop; j++)
|
|
{
|
|
*dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);
|
|
*dp |= (png_byte)(v << dshift);
|
|
if (dshift == s_end)
|
|
{
|
|
dshift = s_start;
|
|
dp--;
|
|
}
|
|
else
|
|
dshift += s_inc;
|
|
}
|
|
if (sshift == s_end)
|
|
{
|
|
sshift = s_start;
|
|
sp--;
|
|
}
|
|
else
|
|
sshift += s_inc;
|
|
}
|
|
break;
|
|
}
|
|
case 4:
|
|
{
|
|
png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);
|
|
png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);
|
|
int sshift, dshift;
|
|
int s_start, s_end, s_inc;
|
|
png_uint_32 i;
|
|
int jstop = png_pass_inc[pass];
|
|
|
|
#ifdef PNG_READ_PACKSWAP_SUPPORTED
|
|
if (transformations & PNG_PACKSWAP)
|
|
{
|
|
sshift = (int)(((row_info->width + 1) & 0x01) << 2);
|
|
dshift = (int)(((final_width + 1) & 0x01) << 2);
|
|
s_start = 4;
|
|
s_end = 0;
|
|
s_inc = -4;
|
|
}
|
|
else
|
|
#endif
|
|
{
|
|
sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2);
|
|
dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2);
|
|
s_start = 0;
|
|
s_end = 4;
|
|
s_inc = 4;
|
|
}
|
|
|
|
for (i = 0; i < row_info->width; i++)
|
|
{
|
|
png_byte v = (png_byte)((*sp >> sshift) & 0xf);
|
|
int j;
|
|
|
|
for (j = 0; j < jstop; j++)
|
|
{
|
|
*dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);
|
|
*dp |= (png_byte)(v << dshift);
|
|
if (dshift == s_end)
|
|
{
|
|
dshift = s_start;
|
|
dp--;
|
|
}
|
|
else
|
|
dshift += s_inc;
|
|
}
|
|
if (sshift == s_end)
|
|
{
|
|
sshift = s_start;
|
|
sp--;
|
|
}
|
|
else
|
|
sshift += s_inc;
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
{
|
|
png_size_t pixel_bytes = (row_info->pixel_depth >> 3);
|
|
png_bytep sp = row + (png_size_t)(row_info->width - 1)
|
|
* pixel_bytes;
|
|
png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;
|
|
|
|
int jstop = png_pass_inc[pass];
|
|
png_uint_32 i;
|
|
|
|
for (i = 0; i < row_info->width; i++)
|
|
{
|
|
png_byte v[8];
|
|
int j;
|
|
|
|
png_memcpy(v, sp, pixel_bytes);
|
|
for (j = 0; j < jstop; j++)
|
|
{
|
|
png_memcpy(dp, v, pixel_bytes);
|
|
dp -= pixel_bytes;
|
|
}
|
|
sp -= pixel_bytes;
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
row_info->width = final_width;
|
|
row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width);
|
|
}
|
|
#ifndef PNG_READ_PACKSWAP_SUPPORTED
|
|
transformations = transformations; /* Silence compiler warning */
|
|
#endif
|
|
}
|
|
#endif /* PNG_READ_INTERLACING_SUPPORTED */
|
|
|
|
void /* PRIVATE */
|
|
png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,
|
|
png_bytep prev_row, int filter)
|
|
{
|
|
png_debug(1, "in png_read_filter_row");
|
|
png_debug2(2, "row = %lu, filter = %d", png_ptr->row_number, filter);
|
|
switch (filter)
|
|
{
|
|
case PNG_FILTER_VALUE_NONE:
|
|
break;
|
|
case PNG_FILTER_VALUE_SUB:
|
|
{
|
|
png_uint_32 i;
|
|
png_uint_32 istop = row_info->rowbytes;
|
|
png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
|
|
png_bytep rp = row + bpp;
|
|
png_bytep lp = row;
|
|
|
|
for (i = bpp; i < istop; i++)
|
|
{
|
|
*rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);
|
|
rp++;
|
|
}
|
|
break;
|
|
}
|
|
case PNG_FILTER_VALUE_UP:
|
|
{
|
|
png_uint_32 i;
|
|
png_uint_32 istop = row_info->rowbytes;
|
|
png_bytep rp = row;
|
|
png_bytep pp = prev_row;
|
|
|
|
for (i = 0; i < istop; i++)
|
|
{
|
|
*rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
|
|
rp++;
|
|
}
|
|
break;
|
|
}
|
|
case PNG_FILTER_VALUE_AVG:
|
|
{
|
|
png_uint_32 i;
|
|
png_bytep rp = row;
|
|
png_bytep pp = prev_row;
|
|
png_bytep lp = row;
|
|
png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
|
|
png_uint_32 istop = row_info->rowbytes - bpp;
|
|
|
|
for (i = 0; i < bpp; i++)
|
|
{
|
|
*rp = (png_byte)(((int)(*rp) +
|
|
((int)(*pp++) / 2 )) & 0xff);
|
|
rp++;
|
|
}
|
|
|
|
for (i = 0; i < istop; i++)
|
|
{
|
|
*rp = (png_byte)(((int)(*rp) +
|
|
(int)(*pp++ + *lp++) / 2 ) & 0xff);
|
|
rp++;
|
|
}
|
|
break;
|
|
}
|
|
case PNG_FILTER_VALUE_PAETH:
|
|
{
|
|
png_uint_32 i;
|
|
png_bytep rp = row;
|
|
png_bytep pp = prev_row;
|
|
png_bytep lp = row;
|
|
png_bytep cp = prev_row;
|
|
png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;
|
|
png_uint_32 istop=row_info->rowbytes - bpp;
|
|
|
|
for (i = 0; i < bpp; i++)
|
|
{
|
|
*rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
|
|
rp++;
|
|
}
|
|
|
|
for (i = 0; i < istop; i++) /* Use leftover rp,pp */
|
|
{
|
|
int a, b, c, pa, pb, pc, p;
|
|
|
|
a = *lp++;
|
|
b = *pp++;
|
|
c = *cp++;
|
|
|
|
p = b - c;
|
|
pc = a - c;
|
|
|
|
#ifdef PNG_USE_ABS
|
|
pa = abs(p);
|
|
pb = abs(pc);
|
|
pc = abs(p + pc);
|
|
#else
|
|
pa = p < 0 ? -p : p;
|
|
pb = pc < 0 ? -pc : pc;
|
|
pc = (p + pc) < 0 ? -(p + pc) : p + pc;
|
|
#endif
|
|
|
|
/*
|
|
if (pa <= pb && pa <= pc)
|
|
p = a;
|
|
else if (pb <= pc)
|
|
p = b;
|
|
else
|
|
p = c;
|
|
*/
|
|
|
|
p = (pa <= pb && pa <= pc) ? a : (pb <= pc) ? b : c;
|
|
|
|
*rp = (png_byte)(((int)(*rp) + p) & 0xff);
|
|
rp++;
|
|
}
|
|
break;
|
|
}
|
|
default:
|
|
png_warning(png_ptr, "Ignoring bad adaptive filter type");
|
|
*row = 0;
|
|
break;
|
|
}
|
|
}
|
|
|
|
#ifdef PNG_INDEX_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_set_interlaced_pass(png_structp png_ptr, int pass)
|
|
{
|
|
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
|
|
/* Start of interlace block */
|
|
PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
|
|
|
|
/* Offset to next interlace block */
|
|
PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
|
|
/* Start of interlace block in the y direction */
|
|
PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
|
|
|
|
/* Offset to next interlace block in the y direction */
|
|
PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
|
|
|
|
png_ptr->pass = pass;
|
|
png_ptr->iwidth = (png_ptr->width +
|
|
png_pass_inc[png_ptr->pass] - 1 -
|
|
png_pass_start[png_ptr->pass]) /
|
|
png_pass_inc[png_ptr->pass];
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_SEQUENTIAL_READ_SUPPORTED
|
|
void /* PRIVATE */
|
|
png_read_finish_row(png_structp png_ptr)
|
|
{
|
|
#ifdef PNG_READ_INTERLACING_SUPPORTED
|
|
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
|
|
/* Start of interlace block */
|
|
PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
|
|
|
|
/* Offset to next interlace block */
|
|
PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
|
|
/* Start of interlace block in the y direction */
|
|
PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
|
|
|
|
/* Offset to next interlace block in the y direction */
|
|
PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
|
|
#endif /* PNG_READ_INTERLACING_SUPPORTED */
|
|
|
|
png_debug(1, "in png_read_finish_row");
|
|
png_ptr->row_number++;
|
|
if (png_ptr->row_number < png_ptr->num_rows)
|
|
return;
|
|
|
|
#ifdef PNG_READ_INTERLACING_SUPPORTED
|
|
if (png_ptr->interlaced)
|
|
{
|
|
png_ptr->row_number = 0;
|
|
png_memset_check(png_ptr, png_ptr->prev_row, 0,
|
|
png_ptr->rowbytes + 1);
|
|
do
|
|
{
|
|
png_ptr->pass++;
|
|
if (png_ptr->pass >= 7)
|
|
break;
|
|
png_ptr->iwidth = (png_ptr->width +
|
|
png_pass_inc[png_ptr->pass] - 1 -
|
|
png_pass_start[png_ptr->pass]) /
|
|
png_pass_inc[png_ptr->pass];
|
|
|
|
if (!(png_ptr->transformations & PNG_INTERLACE))
|
|
{
|
|
png_ptr->num_rows = (png_ptr->height +
|
|
png_pass_yinc[png_ptr->pass] - 1 -
|
|
png_pass_ystart[png_ptr->pass]) /
|
|
png_pass_yinc[png_ptr->pass];
|
|
if (!(png_ptr->num_rows))
|
|
continue;
|
|
}
|
|
else /* if (png_ptr->transformations & PNG_INTERLACE) */
|
|
break;
|
|
} while (png_ptr->iwidth == 0);
|
|
|
|
if (png_ptr->pass < 7)
|
|
return;
|
|
}
|
|
#endif /* PNG_READ_INTERLACING_SUPPORTED */
|
|
|
|
if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))
|
|
{
|
|
#ifdef PNG_USE_LOCAL_ARRAYS
|
|
PNG_CONST PNG_IDAT;
|
|
#endif
|
|
char extra;
|
|
int ret;
|
|
|
|
png_ptr->zstream.next_out = (Byte *)&extra;
|
|
png_ptr->zstream.avail_out = (uInt)1;
|
|
for (;;)
|
|
{
|
|
if (!(png_ptr->zstream.avail_in))
|
|
{
|
|
while (!png_ptr->idat_size)
|
|
{
|
|
png_byte chunk_length[4];
|
|
|
|
png_crc_finish(png_ptr, 0);
|
|
|
|
png_read_data(png_ptr, chunk_length, 4);
|
|
png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length);
|
|
png_reset_crc(png_ptr);
|
|
png_crc_read(png_ptr, png_ptr->chunk_name, 4);
|
|
if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))
|
|
png_error(png_ptr, "Not enough image data");
|
|
|
|
}
|
|
png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;
|
|
png_ptr->zstream.next_in = png_ptr->zbuf;
|
|
if (png_ptr->zbuf_size > png_ptr->idat_size)
|
|
png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;
|
|
png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in);
|
|
png_ptr->idat_size -= png_ptr->zstream.avail_in;
|
|
}
|
|
ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);
|
|
if (ret == Z_STREAM_END)
|
|
{
|
|
if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in ||
|
|
png_ptr->idat_size)
|
|
png_warning(png_ptr, "Extra compressed data.");
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
|
|
break;
|
|
}
|
|
if (ret != Z_OK)
|
|
png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :
|
|
"Decompression Error");
|
|
|
|
if (!(png_ptr->zstream.avail_out))
|
|
{
|
|
png_warning(png_ptr, "Extra compressed data.");
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;
|
|
break;
|
|
}
|
|
|
|
}
|
|
png_ptr->zstream.avail_out = 0;
|
|
}
|
|
|
|
if (png_ptr->idat_size || png_ptr->zstream.avail_in)
|
|
png_warning(png_ptr, "Extra compression data.");
|
|
|
|
inflateReset(&png_ptr->zstream);
|
|
|
|
png_ptr->mode |= PNG_AFTER_IDAT;
|
|
}
|
|
#endif /* PNG_SEQUENTIAL_READ_SUPPORTED */
|
|
|
|
void /* PRIVATE */
|
|
png_read_start_row(png_structp png_ptr)
|
|
{
|
|
#ifdef PNG_READ_INTERLACING_SUPPORTED
|
|
/* Arrays to facilitate easy interlacing - use pass (0 - 6) as index */
|
|
|
|
/* Start of interlace block */
|
|
PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};
|
|
|
|
/* Offset to next interlace block */
|
|
PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};
|
|
|
|
/* Start of interlace block in the y direction */
|
|
PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};
|
|
|
|
/* Offset to next interlace block in the y direction */
|
|
PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};
|
|
#endif
|
|
|
|
int max_pixel_depth;
|
|
png_size_t row_bytes;
|
|
|
|
png_debug(1, "in png_read_start_row");
|
|
png_ptr->zstream.avail_in = 0;
|
|
png_init_read_transformations(png_ptr);
|
|
#ifdef PNG_READ_INTERLACING_SUPPORTED
|
|
if (png_ptr->interlaced)
|
|
{
|
|
if (!(png_ptr->transformations & PNG_INTERLACE))
|
|
png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -
|
|
png_pass_ystart[0]) / png_pass_yinc[0];
|
|
else
|
|
png_ptr->num_rows = png_ptr->height;
|
|
|
|
png_ptr->iwidth = (png_ptr->width +
|
|
png_pass_inc[png_ptr->pass] - 1 -
|
|
png_pass_start[png_ptr->pass]) /
|
|
png_pass_inc[png_ptr->pass];
|
|
}
|
|
else
|
|
#endif /* PNG_READ_INTERLACING_SUPPORTED */
|
|
{
|
|
png_ptr->num_rows = png_ptr->height;
|
|
png_ptr->iwidth = png_ptr->width;
|
|
}
|
|
max_pixel_depth = png_ptr->pixel_depth;
|
|
|
|
#ifdef PNG_READ_PACK_SUPPORTED
|
|
if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)
|
|
max_pixel_depth = 8;
|
|
#endif
|
|
|
|
#ifdef PNG_READ_EXPAND_SUPPORTED
|
|
if (png_ptr->transformations & PNG_EXPAND)
|
|
{
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
{
|
|
if (png_ptr->num_trans)
|
|
max_pixel_depth = 32;
|
|
else
|
|
max_pixel_depth = 24;
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
|
|
{
|
|
if (max_pixel_depth < 8)
|
|
max_pixel_depth = 8;
|
|
if (png_ptr->num_trans)
|
|
max_pixel_depth *= 2;
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
|
|
{
|
|
if (png_ptr->num_trans)
|
|
{
|
|
max_pixel_depth *= 4;
|
|
max_pixel_depth /= 3;
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_FILLER_SUPPORTED
|
|
if (png_ptr->transformations & (PNG_FILLER))
|
|
{
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
|
|
max_pixel_depth = 32;
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)
|
|
{
|
|
if (max_pixel_depth <= 8)
|
|
max_pixel_depth = 16;
|
|
else
|
|
max_pixel_depth = 32;
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
|
|
{
|
|
if (max_pixel_depth <= 32)
|
|
max_pixel_depth = 32;
|
|
else
|
|
max_pixel_depth = 64;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#ifdef PNG_READ_GRAY_TO_RGB_SUPPORTED
|
|
if (png_ptr->transformations & PNG_GRAY_TO_RGB)
|
|
{
|
|
if (
|
|
#ifdef PNG_READ_EXPAND_SUPPORTED
|
|
(png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||
|
|
#endif
|
|
#ifdef PNG_READ_FILLER_SUPPORTED
|
|
(png_ptr->transformations & (PNG_FILLER)) ||
|
|
#endif
|
|
png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
|
|
{
|
|
if (max_pixel_depth <= 16)
|
|
max_pixel_depth = 32;
|
|
else
|
|
max_pixel_depth = 64;
|
|
}
|
|
else
|
|
{
|
|
if (max_pixel_depth <= 8)
|
|
{
|
|
if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
|
|
max_pixel_depth = 32;
|
|
else
|
|
max_pixel_depth = 24;
|
|
}
|
|
else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
|
|
max_pixel_depth = 64;
|
|
else
|
|
max_pixel_depth = 48;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \
|
|
defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)
|
|
if (png_ptr->transformations & PNG_USER_TRANSFORM)
|
|
{
|
|
int user_pixel_depth = png_ptr->user_transform_depth*
|
|
png_ptr->user_transform_channels;
|
|
if (user_pixel_depth > max_pixel_depth)
|
|
max_pixel_depth=user_pixel_depth;
|
|
}
|
|
#endif
|
|
|
|
/* Align the width on the next larger 8 pixels. Mainly used
|
|
* for interlacing
|
|
*/
|
|
row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7));
|
|
/* Calculate the maximum bytes needed, adding a byte and a pixel
|
|
* for safety's sake
|
|
*/
|
|
row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) +
|
|
1 + ((max_pixel_depth + 7) >> 3);
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
if (row_bytes > (png_uint_32)65536L)
|
|
png_error(png_ptr, "This image requires a row greater than 64KB");
|
|
#endif
|
|
|
|
if (row_bytes + 64 > png_ptr->old_big_row_buf_size)
|
|
{
|
|
png_free(png_ptr, png_ptr->big_row_buf);
|
|
if (png_ptr->interlaced)
|
|
png_ptr->big_row_buf = (png_bytep)png_calloc(png_ptr,
|
|
row_bytes + 64);
|
|
else
|
|
png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr,
|
|
row_bytes + 64);
|
|
png_ptr->old_big_row_buf_size = row_bytes + 64;
|
|
|
|
/* Use 32 bytes of padding before and after row_buf. */
|
|
png_ptr->row_buf = png_ptr->big_row_buf + 32;
|
|
png_ptr->old_big_row_buf_size = row_bytes + 64;
|
|
}
|
|
|
|
#ifdef PNG_MAX_MALLOC_64K
|
|
if ((png_uint_32)row_bytes + 1 > (png_uint_32)65536L)
|
|
png_error(png_ptr, "This image requires a row greater than 64KB");
|
|
#endif
|
|
if ((png_uint_32)row_bytes > (png_uint_32)(PNG_SIZE_MAX - 1))
|
|
png_error(png_ptr, "Row has too many bytes to allocate in memory.");
|
|
|
|
if (row_bytes + 1 > png_ptr->old_prev_row_size)
|
|
{
|
|
png_free(png_ptr, png_ptr->prev_row);
|
|
png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)(
|
|
row_bytes + 1));
|
|
png_memset_check(png_ptr, png_ptr->prev_row, 0, row_bytes + 1);
|
|
png_ptr->old_prev_row_size = row_bytes + 1;
|
|
}
|
|
|
|
png_ptr->rowbytes = row_bytes;
|
|
|
|
png_debug1(3, "width = %lu,", png_ptr->width);
|
|
png_debug1(3, "height = %lu,", png_ptr->height);
|
|
png_debug1(3, "iwidth = %lu,", png_ptr->iwidth);
|
|
png_debug1(3, "num_rows = %lu,", png_ptr->num_rows);
|
|
png_debug1(3, "rowbytes = %lu,", png_ptr->rowbytes);
|
|
png_debug1(3, "irowbytes = %lu",
|
|
PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1);
|
|
|
|
png_ptr->flags |= PNG_FLAG_ROW_INIT;
|
|
}
|
|
#endif /* PNG_READ_SUPPORTED */
|