/src/compiler/android/jni/ftk/pngrutil.c
C | 2274 lines | 1849 code | 285 blank | 140 comment | 404 complexity | 6dd551fbad69fa49ae32c4118455856f MD5 | raw file
Possible License(s): LGPL-3.0
- /* pngrutil.c - utilities to read a PNG file
- *
- * Last changed in libpng 1.2.44 [June 26, 2010]
- * Copyright (c) 1998-2010 Glenn Randers-Pehrson
- * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
- * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
- *
- * This code is released under the libpng license.
- * For conditions of distribution and use, see the disclaimer
- * and license in png.h
- *
- * This file contains routines that are only called from within
- * libpng itself during the course of reading an image.
- */
- #define PNG_INTERNAL
- #define PNG_NO_PEDANTIC_WARNINGS
- #include "png.h"
- #ifdef PNG_READ_SUPPORTED
- #if defined(_WIN32_WCE) && (_WIN32_WCE<0x500)
- # define WIN32_WCE_OLD
- #endif
- #ifdef PNG_FLOATING_POINT_SUPPORTED
- # ifdef WIN32_WCE_OLD
- /* The strtod() function is not supported on WindowsCE */
- __inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr,
- char **endptr)
- {
- double result = 0;
- int len;
- wchar_t *str, *end;
- len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0);
- str = (wchar_t *)png_malloc(png_ptr, len * png_sizeof(wchar_t));
- if ( NULL != str )
- {
- MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len);
- result = wcstod(str, &end);
- len = WideCharToMultiByte(CP_ACP, 0, end, -1, NULL, 0, NULL, NULL);
- *endptr = (char *)nptr + (png_strlen(nptr) - len + 1);
- png_free(png_ptr, str);
- }
- return result;
- }
- # else
- # define png_strtod(p,a,b) strtod(a,b)
- # endif
- #endif
- png_uint_32 PNGAPI
- png_get_uint_31(png_structp png_ptr, png_bytep buf)
- {
- #ifdef PNG_READ_BIG_ENDIAN_SUPPORTED
- png_uint_32 i = png_get_uint_32(buf);
- #else
- /* Avoid an extra function call by inlining the result. */
- png_uint_32 i = ((png_uint_32)(*buf) << 24) +
- ((png_uint_32)(*(buf + 1)) << 16) +
- ((png_uint_32)(*(buf + 2)) << 8) +
- (png_uint_32)(*(buf + 3));
- #endif
- if (i > PNG_UINT_31_MAX)
- png_error(png_ptr, "PNG unsigned integer out of range.");
- return (i);
- }
- #ifndef PNG_READ_BIG_ENDIAN_SUPPORTED
- /* Grab an unsigned 32-bit integer from a buffer in big-endian format. */
- png_uint_32 PNGAPI
- png_get_uint_32(png_bytep buf)
- {
- png_uint_32 i = ((png_uint_32)(*buf) << 24) +
- ((png_uint_32)(*(buf + 1)) << 16) +
- ((png_uint_32)(*(buf + 2)) << 8) +
- (png_uint_32)(*(buf + 3));
- return (i);
- }
- /* Grab a signed 32-bit integer from a buffer in big-endian format. The
- * data is stored in the PNG file in two's complement format, and it is
- * assumed that the machine format for signed integers is the same.
- */
- png_int_32 PNGAPI
- png_get_int_32(png_bytep buf)
- {
- png_int_32 i = ((png_int_32)(*buf) << 24) +
- ((png_int_32)(*(buf + 1)) << 16) +
- ((png_int_32)(*(buf + 2)) << 8) +
- (png_int_32)(*(buf + 3));
- return (i);
- }
- /* Grab an unsigned 16-bit integer from a buffer in big-endian format. */
- png_uint_16 PNGAPI
- png_get_uint_16(png_bytep buf)
- {
- png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) +
- (png_uint_16)(*(buf + 1)));
- return (i);
- }
- #endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */
- /* Read the chunk header (length + type name).
- * Put the type name into png_ptr->chunk_name, and return the length.
- */
- png_uint_32 /* PRIVATE */
- png_read_chunk_header(png_structp png_ptr)
- {
- png_byte buf[8];
- png_uint_32 length;
- /* Read the length and the chunk name */
- png_read_data(png_ptr, buf, 8);
- length = png_get_uint_31(png_ptr, buf);
- /* Put the chunk name into png_ptr->chunk_name */
- png_memcpy(png_ptr->chunk_name, buf + 4, 4);
- png_debug2(0, "Reading %s chunk, length = %lu",
- png_ptr->chunk_name, length);
- /* Reset the crc and run it over the chunk name */
- png_reset_crc(png_ptr);
- png_calculate_crc(png_ptr, png_ptr->chunk_name, 4);
- /* Check to see if chunk name is valid */
- png_check_chunk_name(png_ptr, png_ptr->chunk_name);
- return length;
- }
- /* Read data, and (optionally) run it through the CRC. */
- void /* PRIVATE */
- png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)
- {
- if (png_ptr == NULL)
- return;
- png_read_data(png_ptr, buf, length);
- png_calculate_crc(png_ptr, buf, length);
- }
- #ifdef PNG_INDEX_SUPPORTED
- /* Optionally skip data and then check the CRC. Depending on whether we
- * are reading a ancillary or critical chunk, and how the program has set
- * things up, we may calculate the CRC on the data and print a message.
- * Returns '1' if there was a CRC error, '0' otherwise.
- */
- int /* PRIVATE */
- png_opt_crc_finish(png_structp png_ptr, png_uint_32 skip, int check_crc)
- {
- png_size_t i;
- png_size_t istop = png_ptr->zbuf_size;
- for (i = (png_size_t)skip; i > istop; i -= istop)
- {
- png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);
- }
- if (i)
- {
- png_crc_read(png_ptr, png_ptr->zbuf, i);
- }
- if (png_crc_error(png_ptr))
- {
- if (!check_crc) {
- png_chunk_warning(png_ptr, "CRC error");
- return (1);
- }
- if (((png_ptr->chunk_name[0] & 0x20) && /* Ancillary */
- !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) ||
- (!(png_ptr->chunk_name[0] & 0x20) && /* Critical */
- (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE)))
- {
- png_chunk_warning(png_ptr, "CRC error");
- }
- else
- {
- png_chunk_error(png_ptr, "CRC error");
- }
- return (1);
- }
- return (0);
- }
- #endif
- /* Optionally skip data and then check the CRC. Depending on whether we
- * are reading a ancillary or critical chunk, and how the program has set
- * things up, we may calculate the CRC on the data and print a message.
- * Returns '1' if there was a CRC error, '0' otherwise.
- */
- int /* PRIVATE */
- png_crc_finish(png_structp png_ptr, png_uint_32 skip)
- {
- return png_opt_crc_finish(png_ptr, skip, 1);
- }
- /* Compare the CRC stored in the PNG file with that calculated by libpng from
- * the data it has read thus far.
- */
- int /* PRIVATE */
- png_crc_error(png_structp png_ptr)
- {
- png_byte crc_bytes[4];
- png_uint_32 crc;
- int need_crc = 1;
- if (png_ptr->chunk_name[0] & 0x20) /* ancillary */
- {
- if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==
- (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))
- need_crc = 0;
- }
- else /* critical */
- {
- if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)
- need_crc = 0;
- }
- png_read_data(png_ptr, crc_bytes, 4);
- if (need_crc)
- {
- crc = png_get_uint_32(crc_bytes);
- return ((int)(crc != png_ptr->crc));
- }
- else
- return (0);
- }
- #if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \
- defined(PNG_READ_iCCP_SUPPORTED)
- static png_size_t
- png_inflate(png_structp png_ptr, const png_byte *data, png_size_t size,
- png_bytep output, png_size_t output_size)
- {
- png_size_t count = 0;
- png_ptr->zstream.next_in = (png_bytep)data; /* const_cast: VALID */
- png_ptr->zstream.avail_in = size;
- while (1)
- {
- int ret, avail;
- /* Reset the output buffer each time round - we empty it
- * after every inflate call.
- */
- png_ptr->zstream.next_out = png_ptr->zbuf;
- png_ptr->zstream.avail_out = png_ptr->zbuf_size;
- ret = inflate(&png_ptr->zstream, Z_NO_FLUSH);
- avail = png_ptr->zbuf_size - png_ptr->zstream.avail_out;
- /* First copy/count any new output - but only if we didn't
- * get an error code.
- */
- if ((ret == Z_OK || ret == Z_STREAM_END) && avail > 0)
- {
- if (output != 0 && output_size > count)
- {
- int copy = output_size - count;
- if (avail < copy) copy = avail;
- png_memcpy(output + count, png_ptr->zbuf, copy);
- }
- count += avail;
- }
- if (ret == Z_OK)
- continue;
- /* Termination conditions - always reset the zstream, it
- * must be left in inflateInit state.
- */
- png_ptr->zstream.avail_in = 0;
- inflateReset(&png_ptr->zstream);
- if (ret == Z_STREAM_END)
- return count; /* NOTE: may be zero. */
- /* Now handle the error codes - the API always returns 0
- * and the error message is dumped into the uncompressed
- * buffer if available.
- */
- {
- PNG_CONST char *msg;
- if (png_ptr->zstream.msg != 0)
- msg = png_ptr->zstream.msg;
- else
- {
- #if defined(PNG_STDIO_SUPPORTED) && !defined(_WIN32_WCE)
- char umsg[52];
- switch (ret)
- {
- case Z_BUF_ERROR:
- msg = "Buffer error in compressed datastream in %s chunk";
- break;
- case Z_DATA_ERROR:
- msg = "Data error in compressed datastream in %s chunk";
- break;
- default:
- msg = "Incomplete compressed datastream in %s chunk";
- break;
- }
- png_snprintf(umsg, sizeof umsg, msg, png_ptr->chunk_name);
- msg = umsg;
- #else
- msg = "Damaged compressed datastream in chunk other than IDAT";
- #endif
- }
- png_warning(png_ptr, msg);
- }
- /* 0 means an error - notice that this code simple ignores
- * zero length compressed chunks as a result.
- */
- return 0;
- }
- }
- /*
- * Decompress trailing data in a chunk. The assumption is that chunkdata
- * points at an allocated area holding the contents of a chunk with a
- * trailing compressed part. What we get back is an allocated area
- * holding the original prefix part and an uncompressed version of the
- * trailing part (the malloc area passed in is freed).
- */
- void /* PRIVATE */
- png_decompress_chunk(png_structp png_ptr, int comp_type,
- png_size_t chunklength,
- png_size_t prefix_size, png_size_t *newlength)
- {
- /* The caller should guarantee this */
- if (prefix_size > chunklength)
- {
- /* The recovery is to delete the chunk. */
- png_warning(png_ptr, "invalid chunklength");
- prefix_size = 0; /* To delete everything */
- }
- else if (comp_type == PNG_COMPRESSION_TYPE_BASE)
- {
- png_size_t expanded_size = png_inflate(png_ptr,
- (png_bytep)(png_ptr->chunkdata + prefix_size),
- chunklength - prefix_size,
- 0/*output*/, 0/*output size*/);
- /* Now check the limits on this chunk - if the limit fails the
- * compressed data will be removed, the prefix will remain.
- */
- #ifdef PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED
- if (png_ptr->user_chunk_malloc_max &&
- (prefix_size + expanded_size >= png_ptr->user_chunk_malloc_max - 1))
- #else
- # ifdef PNG_USER_CHUNK_MALLOC_MAX
- if ((PNG_USER_CHUNK_MALLOC_MAX > 0) &&
- prefix_size + expanded_size >= PNG_USER_CHUNK_MALLOC_MAX - 1)
- # endif
- #endif
- png_warning(png_ptr, "Exceeded size limit while expanding chunk");
- /* If the size is zero either there was an error and a message
- * has already been output (warning) or the size really is zero
- * and we have nothing to do - the code will exit through the
- * error case below.
- */
- #if defined(PNG_SET_CHUNK_MALLOC_LIMIT_SUPPORTED) || \
- defined(PNG_USER_CHUNK_MALLOC_MAX)
- else
- #endif
- if (expanded_size > 0)
- {
- /* Success (maybe) - really uncompress the chunk. */
- png_size_t new_size = 0;
- png_charp text = png_malloc_warn(png_ptr,
- prefix_size + expanded_size + 1);
- if (text != NULL)
- {
- png_memcpy(text, png_ptr->chunkdata, prefix_size);
- new_size = png_inflate(png_ptr,
- (png_bytep)(png_ptr->chunkdata + prefix_size),
- chunklength - prefix_size,
- (png_bytep)(text + prefix_size), expanded_size);
- text[prefix_size + expanded_size] = 0; /* just in case */
- if (new_size == expanded_size)
- {
- png_free(png_ptr, png_ptr->chunkdata);
- png_ptr->chunkdata = text;
- *newlength = prefix_size + expanded_size;
- return; /* The success return! */
- }
- png_warning(png_ptr, "png_inflate logic error");
- png_free(png_ptr, text);
- }
- else
- png_warning(png_ptr, "Not enough memory to decompress chunk.");
- }
- }
- else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */
- {
- #if defined(PNG_STDIO_SUPPORTED) && !defined(_WIN32_WCE)
- char umsg[50];
- png_snprintf(umsg, sizeof umsg, "Unknown zTXt compression type %d",
- comp_type);
- png_warning(png_ptr, umsg);
- #else
- png_warning(png_ptr, "Unknown zTXt compression type");
- #endif
- /* The recovery is to simply drop the data. */
- }
- /* Generic error return - leave the prefix, delete the compressed
- * data, reallocate the chunkdata to remove the potentially large
- * amount of compressed data.
- */
- {
- png_charp text = png_malloc_warn(png_ptr, prefix_size + 1);
- if (text != NULL)
- {
- if (prefix_size > 0)
- png_memcpy(text, png_ptr->chunkdata, prefix_size);
- png_free(png_ptr, png_ptr->chunkdata);
- png_ptr->chunkdata = text;
- /* This is an extra zero in the 'uncompressed' part. */
- *(png_ptr->chunkdata + prefix_size) = 0x00;
- }
- /* Ignore a malloc error here - it is safe. */
- }
- *newlength = prefix_size;
- }
- #endif
- /* Read and check the IDHR chunk */
- void /* PRIVATE */
- png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)
- {
- png_byte buf[13];
- png_uint_32 width, height;
- int bit_depth, color_type, compression_type, filter_type;
- int interlace_type;
- png_debug(1, "in png_handle_IHDR");
- if (png_ptr->mode & PNG_HAVE_IHDR)
- png_error(png_ptr, "Out of place IHDR");
- /* Check the length */
- if (length != 13)
- png_error(png_ptr, "Invalid IHDR chunk");
- png_ptr->mode |= PNG_HAVE_IHDR;
- png_crc_read(png_ptr, buf, 13);
- png_crc_finish(png_ptr, 0);
- width = png_get_uint_31(png_ptr, buf);
- height = png_get_uint_31(png_ptr, buf + 4);
- bit_depth = buf[8];
- color_type = buf[9];
- compression_type = buf[10];
- filter_type = buf[11];
- interlace_type = buf[12];
- /* Set internal variables */
- png_ptr->width = width;
- png_ptr->height = height;
- png_ptr->bit_depth = (png_byte)bit_depth;
- png_ptr->interlaced = (png_byte)interlace_type;
- png_ptr->color_type = (png_byte)color_type;
- #ifdef PNG_MNG_FEATURES_SUPPORTED
- png_ptr->filter_type = (png_byte)filter_type;
- #endif
- png_ptr->compression_type = (png_byte)compression_type;
- /* Find number of channels */
- switch (png_ptr->color_type)
- {
- case PNG_COLOR_TYPE_GRAY:
- case PNG_COLOR_TYPE_PALETTE:
- png_ptr->channels = 1;
- break;
- 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;
- }
- 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 ch