--- /dev/null
+\r
+/* pngrutil.c - utilities to read a PNG file\r
+ *\r
+ * Last changed in libpng 1.2.33 [October 31, 2008]\r
+ * For conditions of distribution and use, see copyright notice in png.h\r
+ * Copyright (c) 1998-2008 Glenn Randers-Pehrson\r
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)\r
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)\r
+ *\r
+ * This file contains routines that are only called from within\r
+ * libpng itself during the course of reading an image.\r
+ */\r
+\r
+#define PNG_INTERNAL\r
+#include "png.h"\r
+#if defined(PNG_READ_SUPPORTED)\r
+\r
+#if defined(_WIN32_WCE) && (_WIN32_WCE<0x500)\r
+# define WIN32_WCE_OLD\r
+#endif\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+# if defined(WIN32_WCE_OLD)\r
+/* strtod() function is not supported on WindowsCE */\r
+__inline double png_strtod(png_structp png_ptr, PNG_CONST char *nptr, char **endptr)\r
+{\r
+ double result = 0;\r
+ int len;\r
+ wchar_t *str, *end;\r
+\r
+ len = MultiByteToWideChar(CP_ACP, 0, nptr, -1, NULL, 0);\r
+ str = (wchar_t *)png_malloc(png_ptr, len * png_sizeof(wchar_t));\r
+ if ( NULL != str )\r
+ {\r
+ MultiByteToWideChar(CP_ACP, 0, nptr, -1, str, len);\r
+ result = wcstod(str, &end);\r
+ len = WideCharToMultiByte(CP_ACP, 0, end, -1, NULL, 0, NULL, NULL);\r
+ *endptr = (char *)nptr + (png_strlen(nptr) - len + 1);\r
+ png_free(png_ptr, str);\r
+ }\r
+ return result;\r
+}\r
+# else\r
+# define png_strtod(p,a,b) strtod(a,b)\r
+# endif\r
+#endif\r
+\r
+png_uint_32 PNGAPI\r
+png_get_uint_31(png_structp png_ptr, png_bytep buf)\r
+{\r
+#ifdef PNG_READ_BIG_ENDIAN_SUPPORTED\r
+ png_uint_32 i = png_get_uint_32(buf);\r
+#else\r
+ /* Avoid an extra function call by inlining the result. */\r
+ png_uint_32 i = ((png_uint_32)(*buf) << 24) +\r
+ ((png_uint_32)(*(buf + 1)) << 16) +\r
+ ((png_uint_32)(*(buf + 2)) << 8) +\r
+ (png_uint_32)(*(buf + 3));\r
+#endif\r
+ if (i > PNG_UINT_31_MAX)\r
+ png_error(png_ptr, "PNG unsigned integer out of range.");\r
+ return (i);\r
+}\r
+#ifndef PNG_READ_BIG_ENDIAN_SUPPORTED\r
+/* Grab an unsigned 32-bit integer from a buffer in big-endian format. */\r
+png_uint_32 PNGAPI\r
+png_get_uint_32(png_bytep buf)\r
+{\r
+ png_uint_32 i = ((png_uint_32)(*buf) << 24) +\r
+ ((png_uint_32)(*(buf + 1)) << 16) +\r
+ ((png_uint_32)(*(buf + 2)) << 8) +\r
+ (png_uint_32)(*(buf + 3));\r
+\r
+ return (i);\r
+}\r
+\r
+/* Grab a signed 32-bit integer from a buffer in big-endian format. The\r
+ * data is stored in the PNG file in two's complement format, and it is\r
+ * assumed that the machine format for signed integers is the same. */\r
+png_int_32 PNGAPI\r
+png_get_int_32(png_bytep buf)\r
+{\r
+ png_int_32 i = ((png_int_32)(*buf) << 24) +\r
+ ((png_int_32)(*(buf + 1)) << 16) +\r
+ ((png_int_32)(*(buf + 2)) << 8) +\r
+ (png_int_32)(*(buf + 3));\r
+\r
+ return (i);\r
+}\r
+\r
+/* Grab an unsigned 16-bit integer from a buffer in big-endian format. */\r
+png_uint_16 PNGAPI\r
+png_get_uint_16(png_bytep buf)\r
+{\r
+ png_uint_16 i = (png_uint_16)(((png_uint_16)(*buf) << 8) +\r
+ (png_uint_16)(*(buf + 1)));\r
+\r
+ return (i);\r
+}\r
+#endif /* PNG_READ_BIG_ENDIAN_SUPPORTED */\r
+\r
+/* Read the chunk header (length + type name).\r
+ * Put the type name into png_ptr->chunk_name, and return the length.\r
+ */\r
+png_uint_32 /* PRIVATE */\r
+png_read_chunk_header(png_structp png_ptr)\r
+{\r
+ png_byte buf[8];\r
+ png_uint_32 length;\r
+\r
+ /* read the length and the chunk name */\r
+ png_read_data(png_ptr, buf, 8);\r
+ length = png_get_uint_31(png_ptr, buf);\r
+\r
+ /* put the chunk name into png_ptr->chunk_name */\r
+ png_memcpy(png_ptr->chunk_name, buf + 4, 4);\r
+\r
+ png_debug2(0, "Reading %s chunk, length = %lu\n",\r
+ png_ptr->chunk_name, length);\r
+\r
+ /* reset the crc and run it over the chunk name */\r
+ png_reset_crc(png_ptr);\r
+ png_calculate_crc(png_ptr, png_ptr->chunk_name, 4);\r
+\r
+ /* check to see if chunk name is valid */\r
+ png_check_chunk_name(png_ptr, png_ptr->chunk_name);\r
+\r
+ return length;\r
+}\r
+\r
+/* Read data, and (optionally) run it through the CRC. */\r
+void /* PRIVATE */\r
+png_crc_read(png_structp png_ptr, png_bytep buf, png_size_t length)\r
+{\r
+ if (png_ptr == NULL) return;\r
+ png_read_data(png_ptr, buf, length);\r
+ png_calculate_crc(png_ptr, buf, length);\r
+}\r
+\r
+/* Optionally skip data and then check the CRC. Depending on whether we\r
+ are reading a ancillary or critical chunk, and how the program has set\r
+ things up, we may calculate the CRC on the data and print a message.\r
+ Returns '1' if there was a CRC error, '0' otherwise. */\r
+int /* PRIVATE */\r
+png_crc_finish(png_structp png_ptr, png_uint_32 skip)\r
+{\r
+ png_size_t i;\r
+ png_size_t istop = png_ptr->zbuf_size;\r
+\r
+ for (i = (png_size_t)skip; i > istop; i -= istop)\r
+ {\r
+ png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zbuf_size);\r
+ }\r
+ if (i)\r
+ {\r
+ png_crc_read(png_ptr, png_ptr->zbuf, i);\r
+ }\r
+\r
+ if (png_crc_error(png_ptr))\r
+ {\r
+ if (((png_ptr->chunk_name[0] & 0x20) && /* Ancillary */\r
+ !(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)) ||\r
+ (!(png_ptr->chunk_name[0] & 0x20) && /* Critical */\r
+ (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_USE)))\r
+ {\r
+ png_chunk_warning(png_ptr, "CRC error");\r
+ }\r
+ else\r
+ {\r
+ png_chunk_error(png_ptr, "CRC error");\r
+ }\r
+ return (1);\r
+ }\r
+\r
+ return (0);\r
+}\r
+\r
+/* Compare the CRC stored in the PNG file with that calculated by libpng from\r
+ the data it has read thus far. */\r
+int /* PRIVATE */\r
+png_crc_error(png_structp png_ptr)\r
+{\r
+ png_byte crc_bytes[4];\r
+ png_uint_32 crc;\r
+ int need_crc = 1;\r
+\r
+ if (png_ptr->chunk_name[0] & 0x20) /* ancillary */\r
+ {\r
+ if ((png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_MASK) ==\r
+ (PNG_FLAG_CRC_ANCILLARY_USE | PNG_FLAG_CRC_ANCILLARY_NOWARN))\r
+ need_crc = 0;\r
+ }\r
+ else /* critical */\r
+ {\r
+ if (png_ptr->flags & PNG_FLAG_CRC_CRITICAL_IGNORE)\r
+ need_crc = 0;\r
+ }\r
+\r
+ png_read_data(png_ptr, crc_bytes, 4);\r
+\r
+ if (need_crc)\r
+ {\r
+ crc = png_get_uint_32(crc_bytes);\r
+ return ((int)(crc != png_ptr->crc));\r
+ }\r
+ else\r
+ return (0);\r
+}\r
+\r
+#if defined(PNG_READ_zTXt_SUPPORTED) || defined(PNG_READ_iTXt_SUPPORTED) || \\r
+ defined(PNG_READ_iCCP_SUPPORTED)\r
+/*\r
+ * Decompress trailing data in a chunk. The assumption is that chunkdata\r
+ * points at an allocated area holding the contents of a chunk with a\r
+ * trailing compressed part. What we get back is an allocated area\r
+ * holding the original prefix part and an uncompressed version of the\r
+ * trailing part (the malloc area passed in is freed).\r
+ */\r
+void /* PRIVATE */\r
+png_decompress_chunk(png_structp png_ptr, int comp_type,\r
+ png_size_t chunklength,\r
+ png_size_t prefix_size, png_size_t *newlength)\r
+{\r
+ static PNG_CONST char msg[] = "Error decoding compressed text";\r
+ png_charp text;\r
+ png_size_t text_size;\r
+\r
+ if (comp_type == PNG_COMPRESSION_TYPE_BASE)\r
+ {\r
+ int ret = Z_OK;\r
+ png_ptr->zstream.next_in = (png_bytep)(png_ptr->chunkdata + prefix_size);\r
+ png_ptr->zstream.avail_in = (uInt)(chunklength - prefix_size);\r
+ png_ptr->zstream.next_out = png_ptr->zbuf;\r
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;\r
+\r
+ text_size = 0;\r
+ text = NULL;\r
+\r
+ while (png_ptr->zstream.avail_in)\r
+ {\r
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);\r
+ if (ret != Z_OK && ret != Z_STREAM_END)\r
+ {\r
+ if (png_ptr->zstream.msg != NULL)\r
+ png_warning(png_ptr, png_ptr->zstream.msg);\r
+ else\r
+ png_warning(png_ptr, msg);\r
+ inflateReset(&png_ptr->zstream);\r
+ png_ptr->zstream.avail_in = 0;\r
+\r
+ if (text == NULL)\r
+ {\r
+ text_size = prefix_size + png_sizeof(msg) + 1;\r
+ text = (png_charp)png_malloc_warn(png_ptr, text_size);\r
+ if (text == NULL)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_error(png_ptr, "Not enough memory to decompress chunk");\r
+ }\r
+ png_memcpy(text, png_ptr->chunkdata, prefix_size);\r
+ }\r
+\r
+ text[text_size - 1] = 0x00;\r
+\r
+ /* Copy what we can of the error message into the text chunk */\r
+ text_size = (png_size_t)(chunklength -\r
+ (text - png_ptr->chunkdata) - 1);\r
+ if (text_size > png_sizeof(msg))\r
+ text_size = png_sizeof(msg);\r
+ png_memcpy(text + prefix_size, msg, text_size);\r
+ break;\r
+ }\r
+ if (!png_ptr->zstream.avail_out || ret == Z_STREAM_END)\r
+ {\r
+ if (text == NULL)\r
+ {\r
+ text_size = prefix_size +\r
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out;\r
+ text = (png_charp)png_malloc_warn(png_ptr, text_size + 1);\r
+ if (text == NULL)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_error(png_ptr,\r
+ "Not enough memory to decompress chunk.");\r
+ }\r
+ png_memcpy(text + prefix_size, png_ptr->zbuf,\r
+ text_size - prefix_size);\r
+ png_memcpy(text, png_ptr->chunkdata, prefix_size);\r
+ *(text + text_size) = 0x00;\r
+ }\r
+ else\r
+ {\r
+ png_charp tmp;\r
+\r
+ tmp = text;\r
+ text = (png_charp)png_malloc_warn(png_ptr,\r
+ (png_uint_32)(text_size +\r
+ png_ptr->zbuf_size - png_ptr->zstream.avail_out + 1));\r
+ if (text == NULL)\r
+ {\r
+ png_free(png_ptr, tmp);\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_error(png_ptr,\r
+ "Not enough memory to decompress chunk..");\r
+ }\r
+ png_memcpy(text, tmp, text_size);\r
+ png_free(png_ptr, tmp);\r
+ png_memcpy(text + text_size, png_ptr->zbuf,\r
+ (png_ptr->zbuf_size - png_ptr->zstream.avail_out));\r
+ text_size += png_ptr->zbuf_size - png_ptr->zstream.avail_out;\r
+ *(text + text_size) = 0x00;\r
+ }\r
+ if (ret == Z_STREAM_END)\r
+ break;\r
+ else\r
+ {\r
+ png_ptr->zstream.next_out = png_ptr->zbuf;\r
+ png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;\r
+ }\r
+ }\r
+ }\r
+ if (ret != Z_STREAM_END)\r
+ {\r
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)\r
+ char umsg[52];\r
+\r
+ if (ret == Z_BUF_ERROR)\r
+ png_snprintf(umsg, 52,\r
+ "Buffer error in compressed datastream in %s chunk",\r
+ png_ptr->chunk_name);\r
+ else if (ret == Z_DATA_ERROR)\r
+ png_snprintf(umsg, 52,\r
+ "Data error in compressed datastream in %s chunk",\r
+ png_ptr->chunk_name);\r
+ else\r
+ png_snprintf(umsg, 52,\r
+ "Incomplete compressed datastream in %s chunk",\r
+ png_ptr->chunk_name);\r
+ png_warning(png_ptr, umsg);\r
+#else\r
+ png_warning(png_ptr,\r
+ "Incomplete compressed datastream in chunk other than IDAT");\r
+#endif\r
+ text_size = prefix_size;\r
+ if (text == NULL)\r
+ {\r
+ text = (png_charp)png_malloc_warn(png_ptr, text_size+1);\r
+ if (text == NULL)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_error(png_ptr, "Not enough memory for text.");\r
+ }\r
+ png_memcpy(text, png_ptr->chunkdata, prefix_size);\r
+ }\r
+ *(text + text_size) = 0x00;\r
+ }\r
+\r
+ inflateReset(&png_ptr->zstream);\r
+ png_ptr->zstream.avail_in = 0;\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = text;\r
+ *newlength=text_size;\r
+ }\r
+ else /* if (comp_type != PNG_COMPRESSION_TYPE_BASE) */\r
+ {\r
+#if !defined(PNG_NO_STDIO) && !defined(_WIN32_WCE)\r
+ char umsg[50];\r
+\r
+ png_snprintf(umsg, 50, "Unknown zTXt compression type %d", comp_type);\r
+ png_warning(png_ptr, umsg);\r
+#else\r
+ png_warning(png_ptr, "Unknown zTXt compression type");\r
+#endif\r
+\r
+ *(png_ptr->chunkdata + prefix_size) = 0x00;\r
+ *newlength = prefix_size;\r
+ }\r
+}\r
+#endif\r
+\r
+/* read and check the IDHR chunk */\r
+void /* PRIVATE */\r
+png_handle_IHDR(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_byte buf[13];\r
+ png_uint_32 width, height;\r
+ int bit_depth, color_type, compression_type, filter_type;\r
+ int interlace_type;\r
+\r
+ png_debug(1, "in png_handle_IHDR\n");\r
+\r
+ if (png_ptr->mode & PNG_HAVE_IHDR)\r
+ png_error(png_ptr, "Out of place IHDR");\r
+\r
+ /* check the length */\r
+ if (length != 13)\r
+ png_error(png_ptr, "Invalid IHDR chunk");\r
+\r
+ png_ptr->mode |= PNG_HAVE_IHDR;\r
+\r
+ png_crc_read(png_ptr, buf, 13);\r
+ png_crc_finish(png_ptr, 0);\r
+\r
+ width = png_get_uint_31(png_ptr, buf);\r
+ height = png_get_uint_31(png_ptr, buf + 4);\r
+ bit_depth = buf[8];\r
+ color_type = buf[9];\r
+ compression_type = buf[10];\r
+ filter_type = buf[11];\r
+ interlace_type = buf[12];\r
+\r
+ /* set internal variables */\r
+ png_ptr->width = width;\r
+ png_ptr->height = height;\r
+ png_ptr->bit_depth = (png_byte)bit_depth;\r
+ png_ptr->interlaced = (png_byte)interlace_type;\r
+ png_ptr->color_type = (png_byte)color_type;\r
+#if defined(PNG_MNG_FEATURES_SUPPORTED)\r
+ png_ptr->filter_type = (png_byte)filter_type;\r
+#endif\r
+ png_ptr->compression_type = (png_byte)compression_type;\r
+\r
+ /* find number of channels */\r
+ switch (png_ptr->color_type)\r
+ {\r
+ case PNG_COLOR_TYPE_GRAY:\r
+ case PNG_COLOR_TYPE_PALETTE:\r
+ png_ptr->channels = 1;\r
+ break;\r
+ case PNG_COLOR_TYPE_RGB:\r
+ png_ptr->channels = 3;\r
+ break;\r
+ case PNG_COLOR_TYPE_GRAY_ALPHA:\r
+ png_ptr->channels = 2;\r
+ break;\r
+ case PNG_COLOR_TYPE_RGB_ALPHA:\r
+ png_ptr->channels = 4;\r
+ break;\r
+ }\r
+\r
+ /* set up other useful info */\r
+ png_ptr->pixel_depth = (png_byte)(png_ptr->bit_depth *\r
+ png_ptr->channels);\r
+ png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->width);\r
+ png_debug1(3, "bit_depth = %d\n", png_ptr->bit_depth);\r
+ png_debug1(3, "channels = %d\n", png_ptr->channels);\r
+ png_debug1(3, "rowbytes = %lu\n", png_ptr->rowbytes);\r
+ png_set_IHDR(png_ptr, info_ptr, width, height, bit_depth,\r
+ color_type, interlace_type, compression_type, filter_type);\r
+}\r
+\r
+/* read and check the palette */\r
+void /* PRIVATE */\r
+png_handle_PLTE(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_color palette[PNG_MAX_PALETTE_LENGTH];\r
+ int num, i;\r
+#ifndef PNG_NO_POINTER_INDEXING\r
+ png_colorp pal_ptr;\r
+#endif\r
+\r
+ png_debug(1, "in png_handle_PLTE\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before PLTE");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid PLTE after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->mode & PNG_HAVE_PLTE)\r
+ png_error(png_ptr, "Duplicate PLTE chunk");\r
+\r
+ png_ptr->mode |= PNG_HAVE_PLTE;\r
+\r
+ if (!(png_ptr->color_type&PNG_COLOR_MASK_COLOR))\r
+ {\r
+ png_warning(png_ptr,\r
+ "Ignoring PLTE chunk in grayscale PNG");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)\r
+ if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)\r
+ {\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+#endif\r
+\r
+ if (length > 3*PNG_MAX_PALETTE_LENGTH || length % 3)\r
+ {\r
+ if (png_ptr->color_type != PNG_COLOR_TYPE_PALETTE)\r
+ {\r
+ png_warning(png_ptr, "Invalid palette chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else\r
+ {\r
+ png_error(png_ptr, "Invalid palette chunk");\r
+ }\r
+ }\r
+\r
+ num = (int)length / 3;\r
+\r
+#ifndef PNG_NO_POINTER_INDEXING\r
+ for (i = 0, pal_ptr = palette; i < num; i++, pal_ptr++)\r
+ {\r
+ png_byte buf[3];\r
+\r
+ png_crc_read(png_ptr, buf, 3);\r
+ pal_ptr->red = buf[0];\r
+ pal_ptr->green = buf[1];\r
+ pal_ptr->blue = buf[2];\r
+ }\r
+#else\r
+ for (i = 0; i < num; i++)\r
+ {\r
+ png_byte buf[3];\r
+\r
+ png_crc_read(png_ptr, buf, 3);\r
+ /* don't depend upon png_color being any order */\r
+ palette[i].red = buf[0];\r
+ palette[i].green = buf[1];\r
+ palette[i].blue = buf[2];\r
+ }\r
+#endif\r
+\r
+ /* If we actually NEED the PLTE chunk (ie for a paletted image), we do\r
+ whatever the normal CRC configuration tells us. However, if we\r
+ have an RGB image, the PLTE can be considered ancillary, so\r
+ we will act as though it is. */\r
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+#endif\r
+ {\r
+ png_crc_finish(png_ptr, 0);\r
+ }\r
+#if !defined(PNG_READ_OPT_PLTE_SUPPORTED)\r
+ else if (png_crc_error(png_ptr)) /* Only if we have a CRC error */\r
+ {\r
+ /* If we don't want to use the data from an ancillary chunk,\r
+ we have two options: an error abort, or a warning and we\r
+ ignore the data in this chunk (which should be OK, since\r
+ it's considered ancillary for a RGB or RGBA image). */\r
+ if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_USE))\r
+ {\r
+ if (png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN)\r
+ {\r
+ png_chunk_error(png_ptr, "CRC error");\r
+ }\r
+ else\r
+ {\r
+ png_chunk_warning(png_ptr, "CRC error");\r
+ return;\r
+ }\r
+ }\r
+ /* Otherwise, we (optionally) emit a warning and use the chunk. */\r
+ else if (!(png_ptr->flags & PNG_FLAG_CRC_ANCILLARY_NOWARN))\r
+ {\r
+ png_chunk_warning(png_ptr, "CRC error");\r
+ }\r
+ }\r
+#endif\r
+\r
+ png_set_PLTE(png_ptr, info_ptr, palette, num);\r
+\r
+#if defined(PNG_READ_tRNS_SUPPORTED)\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ {\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))\r
+ {\r
+ if (png_ptr->num_trans > (png_uint_16)num)\r
+ {\r
+ png_warning(png_ptr, "Truncating incorrect tRNS chunk length");\r
+ png_ptr->num_trans = (png_uint_16)num;\r
+ }\r
+ if (info_ptr->num_trans > (png_uint_16)num)\r
+ {\r
+ png_warning(png_ptr, "Truncating incorrect info tRNS chunk length");\r
+ info_ptr->num_trans = (png_uint_16)num;\r
+ }\r
+ }\r
+ }\r
+#endif\r
+\r
+}\r
+\r
+void /* PRIVATE */\r
+png_handle_IEND(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_debug(1, "in png_handle_IEND\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR) || !(png_ptr->mode & PNG_HAVE_IDAT))\r
+ {\r
+ png_error(png_ptr, "No image in file");\r
+ }\r
+\r
+ png_ptr->mode |= (PNG_AFTER_IDAT | PNG_HAVE_IEND);\r
+\r
+ if (length != 0)\r
+ {\r
+ png_warning(png_ptr, "Incorrect IEND chunk length");\r
+ }\r
+ png_crc_finish(png_ptr, length);\r
+\r
+ info_ptr = info_ptr; /* quiet compiler warnings about unused info_ptr */\r
+}\r
+\r
+#if defined(PNG_READ_gAMA_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_gAMA(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_fixed_point igamma;\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ float file_gamma;\r
+#endif\r
+ png_byte buf[4];\r
+\r
+ png_debug(1, "in png_handle_gAMA\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before gAMA");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid gAMA after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->mode & PNG_HAVE_PLTE)\r
+ /* Should be an error, but we can cope with it */\r
+ png_warning(png_ptr, "Out of place gAMA chunk");\r
+\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA)\r
+#if defined(PNG_READ_sRGB_SUPPORTED)\r
+ && !(info_ptr->valid & PNG_INFO_sRGB)\r
+#endif\r
+ )\r
+ {\r
+ png_warning(png_ptr, "Duplicate gAMA chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (length != 4)\r
+ {\r
+ png_warning(png_ptr, "Incorrect gAMA chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 4);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ igamma = (png_fixed_point)png_get_uint_32(buf);\r
+ /* check for zero gamma */\r
+ if (igamma == 0)\r
+ {\r
+ png_warning(png_ptr,\r
+ "Ignoring gAMA chunk with gamma=0");\r
+ return;\r
+ }\r
+\r
+#if defined(PNG_READ_sRGB_SUPPORTED)\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))\r
+ if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))\r
+ {\r
+ png_warning(png_ptr,\r
+ "Ignoring incorrect gAMA value when sRGB is also present");\r
+#ifndef PNG_NO_CONSOLE_IO\r
+ fprintf(stderr, "gamma = (%d/100000)\n", (int)igamma);\r
+#endif\r
+ return;\r
+ }\r
+#endif /* PNG_READ_sRGB_SUPPORTED */\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ file_gamma = (float)igamma / (float)100000.0;\r
+# ifdef PNG_READ_GAMMA_SUPPORTED\r
+ png_ptr->gamma = file_gamma;\r
+# endif\r
+ png_set_gAMA(png_ptr, info_ptr, file_gamma);\r
+#endif\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ png_set_gAMA_fixed(png_ptr, info_ptr, igamma);\r
+#endif\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_sBIT_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_sBIT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_size_t truelen;\r
+ png_byte buf[4];\r
+\r
+ png_debug(1, "in png_handle_sBIT\n");\r
+\r
+ buf[0] = buf[1] = buf[2] = buf[3] = 0;\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before sBIT");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid sBIT after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->mode & PNG_HAVE_PLTE)\r
+ {\r
+ /* Should be an error, but we can cope with it */\r
+ png_warning(png_ptr, "Out of place sBIT chunk");\r
+ }\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sBIT))\r
+ {\r
+ png_warning(png_ptr, "Duplicate sBIT chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ truelen = 3;\r
+ else\r
+ truelen = (png_size_t)png_ptr->channels;\r
+\r
+ if (length != truelen || length > 4)\r
+ {\r
+ png_warning(png_ptr, "Incorrect sBIT chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, truelen);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)\r
+ {\r
+ png_ptr->sig_bit.red = buf[0];\r
+ png_ptr->sig_bit.green = buf[1];\r
+ png_ptr->sig_bit.blue = buf[2];\r
+ png_ptr->sig_bit.alpha = buf[3];\r
+ }\r
+ else\r
+ {\r
+ png_ptr->sig_bit.gray = buf[0];\r
+ png_ptr->sig_bit.red = buf[0];\r
+ png_ptr->sig_bit.green = buf[0];\r
+ png_ptr->sig_bit.blue = buf[0];\r
+ png_ptr->sig_bit.alpha = buf[1];\r
+ }\r
+ png_set_sBIT(png_ptr, info_ptr, &(png_ptr->sig_bit));\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_cHRM_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_cHRM(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_byte buf[32];\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;\r
+#endif\r
+ png_fixed_point int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,\r
+ int_y_green, int_x_blue, int_y_blue;\r
+\r
+ png_uint_32 uint_x, uint_y;\r
+\r
+ png_debug(1, "in png_handle_cHRM\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before cHRM");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid cHRM after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->mode & PNG_HAVE_PLTE)\r
+ /* Should be an error, but we can cope with it */\r
+ png_warning(png_ptr, "Missing PLTE before cHRM");\r
+\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM)\r
+#if defined(PNG_READ_sRGB_SUPPORTED)\r
+ && !(info_ptr->valid & PNG_INFO_sRGB)\r
+#endif\r
+ )\r
+ {\r
+ png_warning(png_ptr, "Duplicate cHRM chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (length != 32)\r
+ {\r
+ png_warning(png_ptr, "Incorrect cHRM chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 32);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ uint_x = png_get_uint_32(buf);\r
+ uint_y = png_get_uint_32(buf + 4);\r
+ if (uint_x > 80000L || uint_y > 80000L ||\r
+ uint_x + uint_y > 100000L)\r
+ {\r
+ png_warning(png_ptr, "Invalid cHRM white point");\r
+ return;\r
+ }\r
+ int_x_white = (png_fixed_point)uint_x;\r
+ int_y_white = (png_fixed_point)uint_y;\r
+\r
+ uint_x = png_get_uint_32(buf + 8);\r
+ uint_y = png_get_uint_32(buf + 12);\r
+ if (uint_x + uint_y > 100000L)\r
+ {\r
+ png_warning(png_ptr, "Invalid cHRM red point");\r
+ return;\r
+ }\r
+ int_x_red = (png_fixed_point)uint_x;\r
+ int_y_red = (png_fixed_point)uint_y;\r
+\r
+ uint_x = png_get_uint_32(buf + 16);\r
+ uint_y = png_get_uint_32(buf + 20);\r
+ if (uint_x + uint_y > 100000L)\r
+ {\r
+ png_warning(png_ptr, "Invalid cHRM green point");\r
+ return;\r
+ }\r
+ int_x_green = (png_fixed_point)uint_x;\r
+ int_y_green = (png_fixed_point)uint_y;\r
+\r
+ uint_x = png_get_uint_32(buf + 24);\r
+ uint_y = png_get_uint_32(buf + 28);\r
+ if (uint_x + uint_y > 100000L)\r
+ {\r
+ png_warning(png_ptr, "Invalid cHRM blue point");\r
+ return;\r
+ }\r
+ int_x_blue = (png_fixed_point)uint_x;\r
+ int_y_blue = (png_fixed_point)uint_y;\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ white_x = (float)int_x_white / (float)100000.0;\r
+ white_y = (float)int_y_white / (float)100000.0;\r
+ red_x = (float)int_x_red / (float)100000.0;\r
+ red_y = (float)int_y_red / (float)100000.0;\r
+ green_x = (float)int_x_green / (float)100000.0;\r
+ green_y = (float)int_y_green / (float)100000.0;\r
+ blue_x = (float)int_x_blue / (float)100000.0;\r
+ blue_y = (float)int_y_blue / (float)100000.0;\r
+#endif\r
+\r
+#if defined(PNG_READ_sRGB_SUPPORTED)\r
+ if ((info_ptr != NULL) && (info_ptr->valid & PNG_INFO_sRGB))\r
+ {\r
+ if (PNG_OUT_OF_RANGE(int_x_white, 31270, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_y_white, 32900, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_x_red, 64000L, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_y_red, 33000, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_x_green, 30000, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_y_green, 60000L, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_x_blue, 15000, 1000) ||\r
+ PNG_OUT_OF_RANGE(int_y_blue, 6000, 1000))\r
+ {\r
+ png_warning(png_ptr,\r
+ "Ignoring incorrect cHRM value when sRGB is also present");\r
+#ifndef PNG_NO_CONSOLE_IO\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ fprintf(stderr, "wx=%f, wy=%f, rx=%f, ry=%f\n",\r
+ white_x, white_y, red_x, red_y);\r
+ fprintf(stderr, "gx=%f, gy=%f, bx=%f, by=%f\n",\r
+ green_x, green_y, blue_x, blue_y);\r
+#else\r
+ fprintf(stderr, "wx=%ld, wy=%ld, rx=%ld, ry=%ld\n",\r
+ int_x_white, int_y_white, int_x_red, int_y_red);\r
+ fprintf(stderr, "gx=%ld, gy=%ld, bx=%ld, by=%ld\n",\r
+ int_x_green, int_y_green, int_x_blue, int_y_blue);\r
+#endif\r
+#endif /* PNG_NO_CONSOLE_IO */\r
+ }\r
+ return;\r
+ }\r
+#endif /* PNG_READ_sRGB_SUPPORTED */\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ png_set_cHRM(png_ptr, info_ptr,\r
+ white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);\r
+#endif\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ png_set_cHRM_fixed(png_ptr, info_ptr,\r
+ int_x_white, int_y_white, int_x_red, int_y_red, int_x_green,\r
+ int_y_green, int_x_blue, int_y_blue);\r
+#endif\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_sRGB_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_sRGB(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ int intent;\r
+ png_byte buf[1];\r
+\r
+ png_debug(1, "in png_handle_sRGB\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before sRGB");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid sRGB after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->mode & PNG_HAVE_PLTE)\r
+ /* Should be an error, but we can cope with it */\r
+ png_warning(png_ptr, "Out of place sRGB chunk");\r
+\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sRGB))\r
+ {\r
+ png_warning(png_ptr, "Duplicate sRGB chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (length != 1)\r
+ {\r
+ png_warning(png_ptr, "Incorrect sRGB chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 1);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ intent = buf[0];\r
+ /* check for bad intent */\r
+ if (intent >= PNG_sRGB_INTENT_LAST)\r
+ {\r
+ png_warning(png_ptr, "Unknown sRGB intent");\r
+ return;\r
+ }\r
+\r
+#if defined(PNG_READ_gAMA_SUPPORTED) && defined(PNG_READ_GAMMA_SUPPORTED)\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_gAMA))\r
+ {\r
+ png_fixed_point igamma;\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ igamma=info_ptr->int_gamma;\r
+#else\r
+# ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ igamma=(png_fixed_point)(info_ptr->gamma * 100000.);\r
+# endif\r
+#endif\r
+ if (PNG_OUT_OF_RANGE(igamma, 45500L, 500))\r
+ {\r
+ png_warning(png_ptr,\r
+ "Ignoring incorrect gAMA value when sRGB is also present");\r
+#ifndef PNG_NO_CONSOLE_IO\r
+# ifdef PNG_FIXED_POINT_SUPPORTED\r
+ fprintf(stderr, "incorrect gamma=(%d/100000)\n",\r
+ (int)png_ptr->int_gamma);\r
+# else\r
+# ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ fprintf(stderr, "incorrect gamma=%f\n", png_ptr->gamma);\r
+# endif\r
+# endif\r
+#endif\r
+ }\r
+ }\r
+#endif /* PNG_READ_gAMA_SUPPORTED */\r
+\r
+#ifdef PNG_READ_cHRM_SUPPORTED\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_cHRM))\r
+ if (PNG_OUT_OF_RANGE(info_ptr->int_x_white, 31270, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_y_white, 32900, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_x_red, 64000L, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_y_red, 33000, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_x_green, 30000, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_y_green, 60000L, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_x_blue, 15000, 1000) ||\r
+ PNG_OUT_OF_RANGE(info_ptr->int_y_blue, 6000, 1000))\r
+ {\r
+ png_warning(png_ptr,\r
+ "Ignoring incorrect cHRM value when sRGB is also present");\r
+ }\r
+#endif /* PNG_FIXED_POINT_SUPPORTED */\r
+#endif /* PNG_READ_cHRM_SUPPORTED */\r
+\r
+ png_set_sRGB_gAMA_and_cHRM(png_ptr, info_ptr, intent);\r
+}\r
+#endif /* PNG_READ_sRGB_SUPPORTED */\r
+\r
+#if defined(PNG_READ_iCCP_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_iCCP(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+/* Note: this does not properly handle chunks that are > 64K under DOS */\r
+{\r
+ png_byte compression_type;\r
+ png_bytep pC;\r
+ png_charp profile;\r
+ png_uint_32 skip = 0;\r
+ png_uint_32 profile_size, profile_length;\r
+ png_size_t slength, prefix_length, data_length;\r
+\r
+ png_debug(1, "in png_handle_iCCP\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before iCCP");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid iCCP after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->mode & PNG_HAVE_PLTE)\r
+ /* Should be an error, but we can cope with it */\r
+ png_warning(png_ptr, "Out of place iCCP chunk");\r
+\r
+ if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_iCCP))\r
+ {\r
+ png_warning(png_ptr, "Duplicate iCCP chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ if (length > (png_uint_32)65535L)\r
+ {\r
+ png_warning(png_ptr, "iCCP chunk too large to fit in memory");\r
+ skip = length - (png_uint_32)65535L;\r
+ length = (png_uint_32)65535L;\r
+ }\r
+#endif\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1);\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+\r
+ if (png_crc_finish(png_ptr, skip))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_ptr->chunkdata[slength] = 0x00;\r
+\r
+ for (profile = png_ptr->chunkdata; *profile; profile++)\r
+ /* empty loop to find end of name */ ;\r
+\r
+ ++profile;\r
+\r
+ /* there should be at least one zero (the compression type byte)\r
+ following the separator, and we should be on it */\r
+ if ( profile >= png_ptr->chunkdata + slength - 1)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_warning(png_ptr, "Malformed iCCP chunk");\r
+ return;\r
+ }\r
+\r
+ /* compression_type should always be zero */\r
+ compression_type = *profile++;\r
+ if (compression_type)\r
+ {\r
+ png_warning(png_ptr, "Ignoring nonzero compression type in iCCP chunk");\r
+ compression_type = 0x00; /* Reset it to zero (libpng-1.0.6 through 1.0.8\r
+ wrote nonzero) */\r
+ }\r
+\r
+ prefix_length = profile - png_ptr->chunkdata;\r
+ png_decompress_chunk(png_ptr, compression_type,\r
+ slength, prefix_length, &data_length);\r
+\r
+ profile_length = data_length - prefix_length;\r
+\r
+ if ( prefix_length > data_length || profile_length < 4)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_warning(png_ptr, "Profile size field missing from iCCP chunk");\r
+ return;\r
+ }\r
+\r
+ /* Check the profile_size recorded in the first 32 bits of the ICC profile */\r
+ pC = (png_bytep)(png_ptr->chunkdata + prefix_length);\r
+ profile_size = ((*(pC ))<<24) |\r
+ ((*(pC + 1))<<16) |\r
+ ((*(pC + 2))<< 8) |\r
+ ((*(pC + 3)) );\r
+\r
+ if (profile_size < profile_length)\r
+ profile_length = profile_size;\r
+\r
+ if (profile_size > profile_length)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_warning(png_ptr, "Ignoring truncated iCCP profile.");\r
+ return;\r
+ }\r
+\r
+ png_set_iCCP(png_ptr, info_ptr, png_ptr->chunkdata,\r
+ compression_type, png_ptr->chunkdata + prefix_length, profile_length);\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+}\r
+#endif /* PNG_READ_iCCP_SUPPORTED */\r
+\r
+#if defined(PNG_READ_sPLT_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_sPLT(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+/* Note: this does not properly handle chunks that are > 64K under DOS */\r
+{\r
+ png_bytep entry_start;\r
+ png_sPLT_t new_palette;\r
+#ifdef PNG_NO_POINTER_INDEXING\r
+ png_sPLT_entryp pp;\r
+#endif\r
+ int data_length, entry_size, i;\r
+ png_uint_32 skip = 0;\r
+ png_size_t slength;\r
+\r
+ png_debug(1, "in png_handle_sPLT\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before sPLT");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid sPLT after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ if (length > (png_uint_32)65535L)\r
+ {\r
+ png_warning(png_ptr, "sPLT chunk too large to fit in memory");\r
+ skip = length - (png_uint_32)65535L;\r
+ length = (png_uint_32)65535L;\r
+ }\r
+#endif\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = (png_charp)png_malloc(png_ptr, length + 1);\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+\r
+ if (png_crc_finish(png_ptr, skip))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_ptr->chunkdata[slength] = 0x00;\r
+\r
+ for (entry_start = (png_bytep)png_ptr->chunkdata; *entry_start; entry_start++)\r
+ /* empty loop to find end of name */ ;\r
+ ++entry_start;\r
+\r
+ /* a sample depth should follow the separator, and we should be on it */\r
+ if (entry_start > (png_bytep)png_ptr->chunkdata + slength - 2)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_warning(png_ptr, "malformed sPLT chunk");\r
+ return;\r
+ }\r
+\r
+ new_palette.depth = *entry_start++;\r
+ entry_size = (new_palette.depth == 8 ? 6 : 10);\r
+ data_length = (slength - (entry_start - (png_bytep)png_ptr->chunkdata));\r
+\r
+ /* integrity-check the data length */\r
+ if (data_length % entry_size)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_warning(png_ptr, "sPLT chunk has bad length");\r
+ return;\r
+ }\r
+\r
+ new_palette.nentries = (png_int_32) ( data_length / entry_size);\r
+ if ((png_uint_32) new_palette.nentries >\r
+ (png_uint_32) (PNG_SIZE_MAX / png_sizeof(png_sPLT_entry)))\r
+ {\r
+ png_warning(png_ptr, "sPLT chunk too long");\r
+ return;\r
+ }\r
+ new_palette.entries = (png_sPLT_entryp)png_malloc_warn(\r
+ png_ptr, new_palette.nentries * png_sizeof(png_sPLT_entry));\r
+ if (new_palette.entries == NULL)\r
+ {\r
+ png_warning(png_ptr, "sPLT chunk requires too much memory");\r
+ return;\r
+ }\r
+\r
+#ifndef PNG_NO_POINTER_INDEXING\r
+ for (i = 0; i < new_palette.nentries; i++)\r
+ {\r
+ png_sPLT_entryp pp = new_palette.entries + i;\r
+\r
+ if (new_palette.depth == 8)\r
+ {\r
+ pp->red = *entry_start++;\r
+ pp->green = *entry_start++;\r
+ pp->blue = *entry_start++;\r
+ pp->alpha = *entry_start++;\r
+ }\r
+ else\r
+ {\r
+ pp->red = png_get_uint_16(entry_start); entry_start += 2;\r
+ pp->green = png_get_uint_16(entry_start); entry_start += 2;\r
+ pp->blue = png_get_uint_16(entry_start); entry_start += 2;\r
+ pp->alpha = png_get_uint_16(entry_start); entry_start += 2;\r
+ }\r
+ pp->frequency = png_get_uint_16(entry_start); entry_start += 2;\r
+ }\r
+#else\r
+ pp = new_palette.entries;\r
+ for (i = 0; i < new_palette.nentries; i++)\r
+ {\r
+\r
+ if (new_palette.depth == 8)\r
+ {\r
+ pp[i].red = *entry_start++;\r
+ pp[i].green = *entry_start++;\r
+ pp[i].blue = *entry_start++;\r
+ pp[i].alpha = *entry_start++;\r
+ }\r
+ else\r
+ {\r
+ pp[i].red = png_get_uint_16(entry_start); entry_start += 2;\r
+ pp[i].green = png_get_uint_16(entry_start); entry_start += 2;\r
+ pp[i].blue = png_get_uint_16(entry_start); entry_start += 2;\r
+ pp[i].alpha = png_get_uint_16(entry_start); entry_start += 2;\r
+ }\r
+ pp->frequency = png_get_uint_16(entry_start); entry_start += 2;\r
+ }\r
+#endif\r
+\r
+ /* discard all chunk data except the name and stash that */\r
+ new_palette.name = png_ptr->chunkdata;\r
+\r
+ png_set_sPLT(png_ptr, info_ptr, &new_palette, 1);\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_free(png_ptr, new_palette.entries);\r
+}\r
+#endif /* PNG_READ_sPLT_SUPPORTED */\r
+\r
+#if defined(PNG_READ_tRNS_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_tRNS(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_byte readbuf[PNG_MAX_PALETTE_LENGTH];\r
+\r
+ png_debug(1, "in png_handle_tRNS\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before tRNS");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid tRNS after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tRNS))\r
+ {\r
+ png_warning(png_ptr, "Duplicate tRNS chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)\r
+ {\r
+ png_byte buf[2];\r
+\r
+ if (length != 2)\r
+ {\r
+ png_warning(png_ptr, "Incorrect tRNS chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 2);\r
+ png_ptr->num_trans = 1;\r
+ png_ptr->trans_values.gray = png_get_uint_16(buf);\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)\r
+ {\r
+ png_byte buf[6];\r
+\r
+ if (length != 6)\r
+ {\r
+ png_warning(png_ptr, "Incorrect tRNS chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ png_crc_read(png_ptr, buf, (png_size_t)length);\r
+ png_ptr->num_trans = 1;\r
+ png_ptr->trans_values.red = png_get_uint_16(buf);\r
+ png_ptr->trans_values.green = png_get_uint_16(buf + 2);\r
+ png_ptr->trans_values.blue = png_get_uint_16(buf + 4);\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ {\r
+ if (!(png_ptr->mode & PNG_HAVE_PLTE))\r
+ {\r
+ /* Should be an error, but we can cope with it. */\r
+ png_warning(png_ptr, "Missing PLTE before tRNS");\r
+ }\r
+ if (length > (png_uint_32)png_ptr->num_palette ||\r
+ length > PNG_MAX_PALETTE_LENGTH)\r
+ {\r
+ png_warning(png_ptr, "Incorrect tRNS chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ if (length == 0)\r
+ {\r
+ png_warning(png_ptr, "Zero length tRNS chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ png_crc_read(png_ptr, readbuf, (png_size_t)length);\r
+ png_ptr->num_trans = (png_uint_16)length;\r
+ }\r
+ else\r
+ {\r
+ png_warning(png_ptr, "tRNS chunk not allowed with alpha channel");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (png_crc_finish(png_ptr, 0))\r
+ {\r
+ png_ptr->num_trans = 0;\r
+ return;\r
+ }\r
+\r
+ png_set_tRNS(png_ptr, info_ptr, readbuf, png_ptr->num_trans,\r
+ &(png_ptr->trans_values));\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_bKGD_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_bKGD(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_size_t truelen;\r
+ png_byte buf[6];\r
+\r
+ png_debug(1, "in png_handle_bKGD\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before bKGD");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid bKGD after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE &&\r
+ !(png_ptr->mode & PNG_HAVE_PLTE))\r
+ {\r
+ png_warning(png_ptr, "Missing PLTE before bKGD");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_bKGD))\r
+ {\r
+ png_warning(png_ptr, "Duplicate bKGD chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ truelen = 1;\r
+ else if (png_ptr->color_type & PNG_COLOR_MASK_COLOR)\r
+ truelen = 6;\r
+ else\r
+ truelen = 2;\r
+\r
+ if (length != truelen)\r
+ {\r
+ png_warning(png_ptr, "Incorrect bKGD chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, truelen);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ /* We convert the index value into RGB components so that we can allow\r
+ * arbitrary RGB values for background when we have transparency, and\r
+ * so it is easy to determine the RGB values of the background color\r
+ * from the info_ptr struct. */\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ {\r
+ png_ptr->background.index = buf[0];\r
+ if (info_ptr && info_ptr->num_palette)\r
+ {\r
+ if (buf[0] > info_ptr->num_palette)\r
+ {\r
+ png_warning(png_ptr, "Incorrect bKGD chunk index value");\r
+ return;\r
+ }\r
+ png_ptr->background.red =\r
+ (png_uint_16)png_ptr->palette[buf[0]].red;\r
+ png_ptr->background.green =\r
+ (png_uint_16)png_ptr->palette[buf[0]].green;\r
+ png_ptr->background.blue =\r
+ (png_uint_16)png_ptr->palette[buf[0]].blue;\r
+ }\r
+ }\r
+ else if (!(png_ptr->color_type & PNG_COLOR_MASK_COLOR)) /* GRAY */\r
+ {\r
+ png_ptr->background.red =\r
+ png_ptr->background.green =\r
+ png_ptr->background.blue =\r
+ png_ptr->background.gray = png_get_uint_16(buf);\r
+ }\r
+ else\r
+ {\r
+ png_ptr->background.red = png_get_uint_16(buf);\r
+ png_ptr->background.green = png_get_uint_16(buf + 2);\r
+ png_ptr->background.blue = png_get_uint_16(buf + 4);\r
+ }\r
+\r
+ png_set_bKGD(png_ptr, info_ptr, &(png_ptr->background));\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_hIST_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ unsigned int num, i;\r
+ png_uint_16 readbuf[PNG_MAX_PALETTE_LENGTH];\r
+\r
+ png_debug(1, "in png_handle_hIST\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before hIST");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid hIST after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (!(png_ptr->mode & PNG_HAVE_PLTE))\r
+ {\r
+ png_warning(png_ptr, "Missing PLTE before hIST");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_hIST))\r
+ {\r
+ png_warning(png_ptr, "Duplicate hIST chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ num = length / 2 ;\r
+ if (num != (unsigned int) png_ptr->num_palette || num >\r
+ (unsigned int) PNG_MAX_PALETTE_LENGTH)\r
+ {\r
+ png_warning(png_ptr, "Incorrect hIST chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ for (i = 0; i < num; i++)\r
+ {\r
+ png_byte buf[2];\r
+\r
+ png_crc_read(png_ptr, buf, 2);\r
+ readbuf[i] = png_get_uint_16(buf);\r
+ }\r
+\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ png_set_hIST(png_ptr, info_ptr, readbuf);\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_pHYs_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_pHYs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_byte buf[9];\r
+ png_uint_32 res_x, res_y;\r
+ int unit_type;\r
+\r
+ png_debug(1, "in png_handle_pHYs\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before pHYs");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid pHYs after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pHYs))\r
+ {\r
+ png_warning(png_ptr, "Duplicate pHYs chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (length != 9)\r
+ {\r
+ png_warning(png_ptr, "Incorrect pHYs chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 9);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ res_x = png_get_uint_32(buf);\r
+ res_y = png_get_uint_32(buf + 4);\r
+ unit_type = buf[8];\r
+ png_set_pHYs(png_ptr, info_ptr, res_x, res_y, unit_type);\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_oFFs_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_oFFs(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_byte buf[9];\r
+ png_int_32 offset_x, offset_y;\r
+ int unit_type;\r
+\r
+ png_debug(1, "in png_handle_oFFs\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before oFFs");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid oFFs after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_oFFs))\r
+ {\r
+ png_warning(png_ptr, "Duplicate oFFs chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (length != 9)\r
+ {\r
+ png_warning(png_ptr, "Incorrect oFFs chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 9);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ offset_x = png_get_int_32(buf);\r
+ offset_y = png_get_int_32(buf + 4);\r
+ unit_type = buf[8];\r
+ png_set_oFFs(png_ptr, info_ptr, offset_x, offset_y, unit_type);\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_pCAL_SUPPORTED)\r
+/* read the pCAL chunk (described in the PNG Extensions document) */\r
+void /* PRIVATE */\r
+png_handle_pCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_int_32 X0, X1;\r
+ png_byte type, nparams;\r
+ png_charp buf, units, endptr;\r
+ png_charpp params;\r
+ png_size_t slength;\r
+ int i;\r
+\r
+ png_debug(1, "in png_handle_pCAL\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before pCAL");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid pCAL after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_pCAL))\r
+ {\r
+ png_warning(png_ptr, "Duplicate pCAL chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_debug1(2, "Allocating and reading pCAL chunk data (%lu bytes)\n",\r
+ length + 1);\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);\r
+ if (png_ptr->chunkdata == NULL)\r
+ {\r
+ png_warning(png_ptr, "No memory for pCAL purpose.");\r
+ return;\r
+ }\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+\r
+ if (png_crc_finish(png_ptr, 0))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_ptr->chunkdata[slength] = 0x00; /* null terminate the last string */\r
+\r
+ png_debug(3, "Finding end of pCAL purpose string\n");\r
+ for (buf = png_ptr->chunkdata; *buf; buf++)\r
+ /* empty loop */ ;\r
+\r
+ endptr = png_ptr->chunkdata + slength;\r
+\r
+ /* We need to have at least 12 bytes after the purpose string\r
+ in order to get the parameter information. */\r
+ if (endptr <= buf + 12)\r
+ {\r
+ png_warning(png_ptr, "Invalid pCAL data");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_debug(3, "Reading pCAL X0, X1, type, nparams, and units\n");\r
+ X0 = png_get_int_32((png_bytep)buf+1);\r
+ X1 = png_get_int_32((png_bytep)buf+5);\r
+ type = buf[9];\r
+ nparams = buf[10];\r
+ units = buf + 11;\r
+\r
+ png_debug(3, "Checking pCAL equation type and number of parameters\n");\r
+ /* Check that we have the right number of parameters for known\r
+ equation types. */\r
+ if ((type == PNG_EQUATION_LINEAR && nparams != 2) ||\r
+ (type == PNG_EQUATION_BASE_E && nparams != 3) ||\r
+ (type == PNG_EQUATION_ARBITRARY && nparams != 3) ||\r
+ (type == PNG_EQUATION_HYPERBOLIC && nparams != 4))\r
+ {\r
+ png_warning(png_ptr, "Invalid pCAL parameters for equation type");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+ else if (type >= PNG_EQUATION_LAST)\r
+ {\r
+ png_warning(png_ptr, "Unrecognized equation type for pCAL chunk");\r
+ }\r
+\r
+ for (buf = units; *buf; buf++)\r
+ /* Empty loop to move past the units string. */ ;\r
+\r
+ png_debug(3, "Allocating pCAL parameters array\n");\r
+ params = (png_charpp)png_malloc_warn(png_ptr,\r
+ (png_uint_32)(nparams * png_sizeof(png_charp))) ;\r
+ if (params == NULL)\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_warning(png_ptr, "No memory for pCAL params.");\r
+ return;\r
+ }\r
+\r
+ /* Get pointers to the start of each parameter string. */\r
+ for (i = 0; i < (int)nparams; i++)\r
+ {\r
+ buf++; /* Skip the null string terminator from previous parameter. */\r
+\r
+ png_debug1(3, "Reading pCAL parameter %d\n", i);\r
+ for (params[i] = buf; buf <= endptr && *buf != 0x00; buf++)\r
+ /* Empty loop to move past each parameter string */ ;\r
+\r
+ /* Make sure we haven't run out of data yet */\r
+ if (buf > endptr)\r
+ {\r
+ png_warning(png_ptr, "Invalid pCAL data");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_free(png_ptr, params);\r
+ return;\r
+ }\r
+ }\r
+\r
+ png_set_pCAL(png_ptr, info_ptr, png_ptr->chunkdata, X0, X1, type, nparams,\r
+ units, params);\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_free(png_ptr, params);\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_sCAL_SUPPORTED)\r
+/* read the sCAL chunk */\r
+void /* PRIVATE */\r
+png_handle_sCAL(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_charp ep;\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ double width, height;\r
+ png_charp vp;\r
+#else\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ png_charp swidth, sheight;\r
+#endif\r
+#endif\r
+ png_size_t slength;\r
+\r
+ png_debug(1, "in png_handle_sCAL\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before sCAL");\r
+ else if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+ png_warning(png_ptr, "Invalid sCAL after IDAT");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_sCAL))\r
+ {\r
+ png_warning(png_ptr, "Duplicate sCAL chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_debug1(2, "Allocating and reading sCAL chunk data (%lu bytes)\n",\r
+ length + 1);\r
+ png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);\r
+ if (png_ptr->chunkdata == NULL)\r
+ {\r
+ png_warning(png_ptr, "Out of memory while processing sCAL chunk");\r
+ return;\r
+ }\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+\r
+ if (png_crc_finish(png_ptr, 0))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_ptr->chunkdata[slength] = 0x00; /* null terminate the last string */\r
+\r
+ ep = png_ptr->chunkdata + 1; /* skip unit byte */\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ width = png_strtod(png_ptr, ep, &vp);\r
+ if (*vp)\r
+ {\r
+ png_warning(png_ptr, "malformed width string in sCAL chunk");\r
+ return;\r
+ }\r
+#else\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ swidth = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);\r
+ if (swidth == NULL)\r
+ {\r
+ png_warning(png_ptr, "Out of memory while processing sCAL chunk width");\r
+ return;\r
+ }\r
+ png_memcpy(swidth, ep, (png_size_t)png_strlen(ep));\r
+#endif\r
+#endif\r
+\r
+ for (ep = png_ptr->chunkdata; *ep; ep++)\r
+ /* empty loop */ ;\r
+ ep++;\r
+\r
+ if (png_ptr->chunkdata + slength < ep)\r
+ {\r
+ png_warning(png_ptr, "Truncated sCAL chunk");\r
+#if defined(PNG_FIXED_POINT_SUPPORTED) && \\r
+ !defined(PNG_FLOATING_POINT_SUPPORTED)\r
+ png_free(png_ptr, swidth);\r
+#endif\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ height = png_strtod(png_ptr, ep, &vp);\r
+ if (*vp)\r
+ {\r
+ png_warning(png_ptr, "malformed height string in sCAL chunk");\r
+ return;\r
+ }\r
+#else\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ sheight = (png_charp)png_malloc_warn(png_ptr, png_strlen(ep) + 1);\r
+ if (sheight == NULL)\r
+ {\r
+ png_warning(png_ptr, "Out of memory while processing sCAL chunk height");\r
+ return;\r
+ }\r
+ png_memcpy(sheight, ep, (png_size_t)png_strlen(ep));\r
+#endif\r
+#endif\r
+\r
+ if (png_ptr->chunkdata + slength < ep\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ || width <= 0. || height <= 0.\r
+#endif\r
+ )\r
+ {\r
+ png_warning(png_ptr, "Invalid sCAL data");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)\r
+ png_free(png_ptr, swidth);\r
+ png_free(png_ptr, sheight);\r
+#endif\r
+ return;\r
+ }\r
+\r
+\r
+#ifdef PNG_FLOATING_POINT_SUPPORTED\r
+ png_set_sCAL(png_ptr, info_ptr, png_ptr->chunkdata[0], width, height);\r
+#else\r
+#ifdef PNG_FIXED_POINT_SUPPORTED\r
+ png_set_sCAL_s(png_ptr, info_ptr, png_ptr->chunkdata[0], swidth, sheight);\r
+#endif\r
+#endif\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+#if defined(PNG_FIXED_POINT_SUPPORTED) && !defined(PNG_FLOATING_POINT_SUPPORTED)\r
+ png_free(png_ptr, swidth);\r
+ png_free(png_ptr, sheight);\r
+#endif\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_tIME_SUPPORTED)\r
+void /* PRIVATE */\r
+png_handle_tIME(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_byte buf[7];\r
+ png_time mod_time;\r
+\r
+ png_debug(1, "in png_handle_tIME\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Out of place tIME chunk");\r
+ else if (info_ptr != NULL && (info_ptr->valid & PNG_INFO_tIME))\r
+ {\r
+ png_warning(png_ptr, "Duplicate tIME chunk");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+\r
+ if (length != 7)\r
+ {\r
+ png_warning(png_ptr, "Incorrect tIME chunk length");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+\r
+ png_crc_read(png_ptr, buf, 7);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ return;\r
+\r
+ mod_time.second = buf[6];\r
+ mod_time.minute = buf[5];\r
+ mod_time.hour = buf[4];\r
+ mod_time.day = buf[3];\r
+ mod_time.month = buf[2];\r
+ mod_time.year = png_get_uint_16(buf);\r
+\r
+ png_set_tIME(png_ptr, info_ptr, &mod_time);\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_tEXt_SUPPORTED)\r
+/* Note: this does not properly handle chunks that are > 64K under DOS */\r
+void /* PRIVATE */\r
+png_handle_tEXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_textp text_ptr;\r
+ png_charp key;\r
+ png_charp text;\r
+ png_uint_32 skip = 0;\r
+ png_size_t slength;\r
+ int ret;\r
+\r
+ png_debug(1, "in png_handle_tEXt\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before tEXt");\r
+\r
+ if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ if (length > (png_uint_32)65535L)\r
+ {\r
+ png_warning(png_ptr, "tEXt chunk too large to fit in memory");\r
+ skip = length - (png_uint_32)65535L;\r
+ length = (png_uint_32)65535L;\r
+ }\r
+#endif\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);\r
+ if (png_ptr->chunkdata == NULL)\r
+ {\r
+ png_warning(png_ptr, "No memory to process text chunk.");\r
+ return;\r
+ }\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+\r
+ if (png_crc_finish(png_ptr, skip))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ key = png_ptr->chunkdata;\r
+ key[slength] = 0x00;\r
+\r
+ for (text = key; *text; text++)\r
+ /* empty loop to find end of key */ ;\r
+\r
+ if (text != key + slength)\r
+ text++;\r
+\r
+ text_ptr = (png_textp)png_malloc_warn(png_ptr,\r
+ (png_uint_32)png_sizeof(png_text));\r
+ if (text_ptr == NULL)\r
+ {\r
+ png_warning(png_ptr, "Not enough memory to process text chunk.");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+ text_ptr->compression = PNG_TEXT_COMPRESSION_NONE;\r
+ text_ptr->key = key;\r
+#ifdef PNG_iTXt_SUPPORTED\r
+ text_ptr->lang = NULL;\r
+ text_ptr->lang_key = NULL;\r
+ text_ptr->itxt_length = 0;\r
+#endif\r
+ text_ptr->text = text;\r
+ text_ptr->text_length = png_strlen(text);\r
+\r
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ png_free(png_ptr, text_ptr);\r
+ if (ret)\r
+ png_warning(png_ptr, "Insufficient memory to process text chunk.");\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_zTXt_SUPPORTED)\r
+/* note: this does not correctly handle chunks that are > 64K under DOS */\r
+void /* PRIVATE */\r
+png_handle_zTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_textp text_ptr;\r
+ png_charp text;\r
+ int comp_type;\r
+ int ret;\r
+ png_size_t slength, prefix_len, data_len;\r
+\r
+ png_debug(1, "in png_handle_zTXt\n");\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before zTXt");\r
+\r
+ if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ /* We will no doubt have problems with chunks even half this size, but\r
+ there is no hard and fast rule to tell us where to stop. */\r
+ if (length > (png_uint_32)65535L)\r
+ {\r
+ png_warning(png_ptr, "zTXt chunk too large to fit in memory");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+#endif\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);\r
+ if (png_ptr->chunkdata == NULL)\r
+ {\r
+ png_warning(png_ptr, "Out of memory processing zTXt chunk.");\r
+ return;\r
+ }\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_ptr->chunkdata[slength] = 0x00;\r
+\r
+ for (text = png_ptr->chunkdata; *text; text++)\r
+ /* empty loop */ ;\r
+\r
+ /* zTXt must have some text after the chunkdataword */\r
+ if (text >= png_ptr->chunkdata + slength - 2)\r
+ {\r
+ png_warning(png_ptr, "Truncated zTXt chunk");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+ else\r
+ {\r
+ comp_type = *(++text);\r
+ if (comp_type != PNG_TEXT_COMPRESSION_zTXt)\r
+ {\r
+ png_warning(png_ptr, "Unknown compression type in zTXt chunk");\r
+ comp_type = PNG_TEXT_COMPRESSION_zTXt;\r
+ }\r
+ text++; /* skip the compression_method byte */\r
+ }\r
+ prefix_len = text - png_ptr->chunkdata;\r
+\r
+ png_decompress_chunk(png_ptr, comp_type,\r
+ (png_size_t)length, prefix_len, &data_len);\r
+\r
+ text_ptr = (png_textp)png_malloc_warn(png_ptr,\r
+ (png_uint_32)png_sizeof(png_text));\r
+ if (text_ptr == NULL)\r
+ {\r
+ png_warning(png_ptr, "Not enough memory to process zTXt chunk.");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+ text_ptr->compression = comp_type;\r
+ text_ptr->key = png_ptr->chunkdata;\r
+#ifdef PNG_iTXt_SUPPORTED\r
+ text_ptr->lang = NULL;\r
+ text_ptr->lang_key = NULL;\r
+ text_ptr->itxt_length = 0;\r
+#endif\r
+ text_ptr->text = png_ptr->chunkdata + prefix_len;\r
+ text_ptr->text_length = data_len;\r
+\r
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);\r
+\r
+ png_free(png_ptr, text_ptr);\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ if (ret)\r
+ png_error(png_ptr, "Insufficient memory to store zTXt chunk.");\r
+}\r
+#endif\r
+\r
+#if defined(PNG_READ_iTXt_SUPPORTED)\r
+/* note: this does not correctly handle chunks that are > 64K under DOS */\r
+void /* PRIVATE */\r
+png_handle_iTXt(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_textp text_ptr;\r
+ png_charp key, lang, text, lang_key;\r
+ int comp_flag;\r
+ int comp_type = 0;\r
+ int ret;\r
+ png_size_t slength, prefix_len, data_len;\r
+\r
+ png_debug(1, "in png_handle_iTXt\n");\r
+\r
+ if (!(png_ptr->mode & PNG_HAVE_IHDR))\r
+ png_error(png_ptr, "Missing IHDR before iTXt");\r
+\r
+ if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ /* We will no doubt have problems with chunks even half this size, but\r
+ there is no hard and fast rule to tell us where to stop. */\r
+ if (length > (png_uint_32)65535L)\r
+ {\r
+ png_warning(png_ptr, "iTXt chunk too large to fit in memory");\r
+ png_crc_finish(png_ptr, length);\r
+ return;\r
+ }\r
+#endif\r
+\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = (png_charp)png_malloc_warn(png_ptr, length + 1);\r
+ if (png_ptr->chunkdata == NULL)\r
+ {\r
+ png_warning(png_ptr, "No memory to process iTXt chunk.");\r
+ return;\r
+ }\r
+ slength = (png_size_t)length;\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->chunkdata, slength);\r
+ if (png_crc_finish(png_ptr, 0))\r
+ {\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ png_ptr->chunkdata[slength] = 0x00;\r
+\r
+ for (lang = png_ptr->chunkdata; *lang; lang++)\r
+ /* empty loop */ ;\r
+ lang++; /* skip NUL separator */\r
+\r
+ /* iTXt must have a language tag (possibly empty), two compression bytes,\r
+ translated keyword (possibly empty), and possibly some text after the\r
+ keyword */\r
+\r
+ if (lang >= png_ptr->chunkdata + slength - 3)\r
+ {\r
+ png_warning(png_ptr, "Truncated iTXt chunk");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+ else\r
+ {\r
+ comp_flag = *lang++;\r
+ comp_type = *lang++;\r
+ }\r
+\r
+ for (lang_key = lang; *lang_key; lang_key++)\r
+ /* empty loop */ ;\r
+ lang_key++; /* skip NUL separator */\r
+\r
+ if (lang_key >= png_ptr->chunkdata + slength)\r
+ {\r
+ png_warning(png_ptr, "Truncated iTXt chunk");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ for (text = lang_key; *text; text++)\r
+ /* empty loop */ ;\r
+ text++; /* skip NUL separator */\r
+ if (text >= png_ptr->chunkdata + slength)\r
+ {\r
+ png_warning(png_ptr, "Malformed iTXt chunk");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+\r
+ prefix_len = text - png_ptr->chunkdata;\r
+\r
+ key=png_ptr->chunkdata;\r
+ if (comp_flag)\r
+ png_decompress_chunk(png_ptr, comp_type,\r
+ (size_t)length, prefix_len, &data_len);\r
+ else\r
+ data_len = png_strlen(png_ptr->chunkdata + prefix_len);\r
+ text_ptr = (png_textp)png_malloc_warn(png_ptr,\r
+ (png_uint_32)png_sizeof(png_text));\r
+ if (text_ptr == NULL)\r
+ {\r
+ png_warning(png_ptr, "Not enough memory to process iTXt chunk.");\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ return;\r
+ }\r
+ text_ptr->compression = (int)comp_flag + 1;\r
+ text_ptr->lang_key = png_ptr->chunkdata + (lang_key - key);\r
+ text_ptr->lang = png_ptr->chunkdata + (lang - key);\r
+ text_ptr->itxt_length = data_len;\r
+ text_ptr->text_length = 0;\r
+ text_ptr->key = png_ptr->chunkdata;\r
+ text_ptr->text = png_ptr->chunkdata + prefix_len;\r
+\r
+ ret = png_set_text_2(png_ptr, info_ptr, text_ptr, 1);\r
+\r
+ png_free(png_ptr, text_ptr);\r
+ png_free(png_ptr, png_ptr->chunkdata);\r
+ png_ptr->chunkdata = NULL;\r
+ if (ret)\r
+ png_error(png_ptr, "Insufficient memory to store iTXt chunk.");\r
+}\r
+#endif\r
+\r
+/* This function is called when we haven't found a handler for a\r
+ chunk. If there isn't a problem with the chunk itself (ie bad\r
+ chunk name, CRC, or a critical chunk), the chunk is silently ignored\r
+ -- unless the PNG_FLAG_UNKNOWN_CHUNKS_SUPPORTED flag is on in which\r
+ case it will be saved away to be written out later. */\r
+void /* PRIVATE */\r
+png_handle_unknown(png_structp png_ptr, png_infop info_ptr, png_uint_32 length)\r
+{\r
+ png_uint_32 skip = 0;\r
+\r
+ png_debug(1, "in png_handle_unknown\n");\r
+\r
+ if (png_ptr->mode & PNG_HAVE_IDAT)\r
+ {\r
+#ifdef PNG_USE_LOCAL_ARRAYS\r
+ PNG_CONST PNG_IDAT;\r
+#endif\r
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4)) /* not an IDAT */\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+ }\r
+\r
+ if (!(png_ptr->chunk_name[0] & 0x20))\r
+ {\r
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)\r
+ if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=\r
+ PNG_HANDLE_CHUNK_ALWAYS\r
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)\r
+ && png_ptr->read_user_chunk_fn == NULL\r
+#endif\r
+ )\r
+#endif\r
+ png_chunk_error(png_ptr, "unknown critical chunk");\r
+ }\r
+\r
+#if defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED)\r
+ if ((png_ptr->flags & PNG_FLAG_KEEP_UNKNOWN_CHUNKS) ||\r
+ (png_ptr->read_user_chunk_fn != NULL))\r
+ {\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ if (length > (png_uint_32)65535L)\r
+ {\r
+ png_warning(png_ptr, "unknown chunk too large to fit in memory");\r
+ skip = length - (png_uint_32)65535L;\r
+ length = (png_uint_32)65535L;\r
+ }\r
+#endif\r
+ png_memcpy((png_charp)png_ptr->unknown_chunk.name,\r
+ (png_charp)png_ptr->chunk_name, \r
+ png_sizeof(png_ptr->unknown_chunk.name));\r
+ png_ptr->unknown_chunk.name[png_sizeof(png_ptr->unknown_chunk.name)-1] = '\0';\r
+ png_ptr->unknown_chunk.size = (png_size_t)length;\r
+ if (length == 0)\r
+ png_ptr->unknown_chunk.data = NULL;\r
+ else\r
+ {\r
+ png_ptr->unknown_chunk.data = (png_bytep)png_malloc(png_ptr, length);\r
+ png_crc_read(png_ptr, (png_bytep)png_ptr->unknown_chunk.data, length);\r
+ }\r
+#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)\r
+ if (png_ptr->read_user_chunk_fn != NULL)\r
+ {\r
+ /* callback to user unknown chunk handler */\r
+ int ret;\r
+ ret = (*(png_ptr->read_user_chunk_fn))\r
+ (png_ptr, &png_ptr->unknown_chunk);\r
+ if (ret < 0)\r
+ png_chunk_error(png_ptr, "error in user chunk");\r
+ if (ret == 0)\r
+ {\r
+ if (!(png_ptr->chunk_name[0] & 0x20))\r
+ if (png_handle_as_unknown(png_ptr, png_ptr->chunk_name) !=\r
+ PNG_HANDLE_CHUNK_ALWAYS)\r
+ png_chunk_error(png_ptr, "unknown critical chunk");\r
+ png_set_unknown_chunks(png_ptr, info_ptr,\r
+ &png_ptr->unknown_chunk, 1);\r
+ }\r
+ }\r
+ else\r
+#endif\r
+ png_set_unknown_chunks(png_ptr, info_ptr, &png_ptr->unknown_chunk, 1);\r
+ png_free(png_ptr, png_ptr->unknown_chunk.data);\r
+ png_ptr->unknown_chunk.data = NULL;\r
+ }\r
+ else\r
+#endif\r
+ skip = length;\r
+\r
+ png_crc_finish(png_ptr, skip);\r
+\r
+#if !defined(PNG_READ_USER_CHUNKS_SUPPORTED)\r
+ info_ptr = info_ptr; /* quiet compiler warnings about unused info_ptr */\r
+#endif\r
+}\r
+\r
+/* This function is called to verify that a chunk name is valid.\r
+ This function can't have the "critical chunk check" incorporated\r
+ into it, since in the future we will need to be able to call user\r
+ functions to handle unknown critical chunks after we check that\r
+ the chunk name itself is valid. */\r
+\r
+#define isnonalpha(c) ((c) < 65 || (c) > 122 || ((c) > 90 && (c) < 97))\r
+\r
+void /* PRIVATE */\r
+png_check_chunk_name(png_structp png_ptr, png_bytep chunk_name)\r
+{\r
+ png_debug(1, "in png_check_chunk_name\n");\r
+ if (isnonalpha(chunk_name[0]) || isnonalpha(chunk_name[1]) ||\r
+ isnonalpha(chunk_name[2]) || isnonalpha(chunk_name[3]))\r
+ {\r
+ png_chunk_error(png_ptr, "invalid chunk type");\r
+ }\r
+}\r
+\r
+/* Combines the row recently read in with the existing pixels in the\r
+ row. This routine takes care of alpha and transparency if requested.\r
+ This routine also handles the two methods of progressive display\r
+ of interlaced images, depending on the mask value.\r
+ The mask value describes which pixels are to be combined with\r
+ the row. The pattern always repeats every 8 pixels, so just 8\r
+ bits are needed. A one indicates the pixel is to be combined,\r
+ a zero indicates the pixel is to be skipped. This is in addition\r
+ to any alpha or transparency value associated with the pixel. If\r
+ you want all pixels to be combined, pass 0xff (255) in mask. */\r
+\r
+void /* PRIVATE */\r
+png_combine_row(png_structp png_ptr, png_bytep row, int mask)\r
+{\r
+ png_debug(1, "in png_combine_row\n");\r
+ if (mask == 0xff)\r
+ {\r
+ png_memcpy(row, png_ptr->row_buf + 1,\r
+ PNG_ROWBYTES(png_ptr->row_info.pixel_depth, png_ptr->width));\r
+ }\r
+ else\r
+ {\r
+ switch (png_ptr->row_info.pixel_depth)\r
+ {\r
+ case 1:\r
+ {\r
+ png_bytep sp = png_ptr->row_buf + 1;\r
+ png_bytep dp = row;\r
+ int s_inc, s_start, s_end;\r
+ int m = 0x80;\r
+ int shift;\r
+ png_uint_32 i;\r
+ png_uint_32 row_width = png_ptr->width;\r
+\r
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ if (png_ptr->transformations & PNG_PACKSWAP)\r
+ {\r
+ s_start = 0;\r
+ s_end = 7;\r
+ s_inc = 1;\r
+ }\r
+ else\r
+#endif\r
+ {\r
+ s_start = 7;\r
+ s_end = 0;\r
+ s_inc = -1;\r
+ }\r
+\r
+ shift = s_start;\r
+\r
+ for (i = 0; i < row_width; i++)\r
+ {\r
+ if (m & mask)\r
+ {\r
+ int value;\r
+\r
+ value = (*sp >> shift) & 0x01;\r
+ *dp &= (png_byte)((0x7f7f >> (7 - shift)) & 0xff);\r
+ *dp |= (png_byte)(value << shift);\r
+ }\r
+\r
+ if (shift == s_end)\r
+ {\r
+ shift = s_start;\r
+ sp++;\r
+ dp++;\r
+ }\r
+ else\r
+ shift += s_inc;\r
+\r
+ if (m == 1)\r
+ m = 0x80;\r
+ else\r
+ m >>= 1;\r
+ }\r
+ break;\r
+ }\r
+ case 2:\r
+ {\r
+ png_bytep sp = png_ptr->row_buf + 1;\r
+ png_bytep dp = row;\r
+ int s_start, s_end, s_inc;\r
+ int m = 0x80;\r
+ int shift;\r
+ png_uint_32 i;\r
+ png_uint_32 row_width = png_ptr->width;\r
+ int value;\r
+\r
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ if (png_ptr->transformations & PNG_PACKSWAP)\r
+ {\r
+ s_start = 0;\r
+ s_end = 6;\r
+ s_inc = 2;\r
+ }\r
+ else\r
+#endif\r
+ {\r
+ s_start = 6;\r
+ s_end = 0;\r
+ s_inc = -2;\r
+ }\r
+\r
+ shift = s_start;\r
+\r
+ for (i = 0; i < row_width; i++)\r
+ {\r
+ if (m & mask)\r
+ {\r
+ value = (*sp >> shift) & 0x03;\r
+ *dp &= (png_byte)((0x3f3f >> (6 - shift)) & 0xff);\r
+ *dp |= (png_byte)(value << shift);\r
+ }\r
+\r
+ if (shift == s_end)\r
+ {\r
+ shift = s_start;\r
+ sp++;\r
+ dp++;\r
+ }\r
+ else\r
+ shift += s_inc;\r
+ if (m == 1)\r
+ m = 0x80;\r
+ else\r
+ m >>= 1;\r
+ }\r
+ break;\r
+ }\r
+ case 4:\r
+ {\r
+ png_bytep sp = png_ptr->row_buf + 1;\r
+ png_bytep dp = row;\r
+ int s_start, s_end, s_inc;\r
+ int m = 0x80;\r
+ int shift;\r
+ png_uint_32 i;\r
+ png_uint_32 row_width = png_ptr->width;\r
+ int value;\r
+\r
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ if (png_ptr->transformations & PNG_PACKSWAP)\r
+ {\r
+ s_start = 0;\r
+ s_end = 4;\r
+ s_inc = 4;\r
+ }\r
+ else\r
+#endif\r
+ {\r
+ s_start = 4;\r
+ s_end = 0;\r
+ s_inc = -4;\r
+ }\r
+ shift = s_start;\r
+\r
+ for (i = 0; i < row_width; i++)\r
+ {\r
+ if (m & mask)\r
+ {\r
+ value = (*sp >> shift) & 0xf;\r
+ *dp &= (png_byte)((0xf0f >> (4 - shift)) & 0xff);\r
+ *dp |= (png_byte)(value << shift);\r
+ }\r
+\r
+ if (shift == s_end)\r
+ {\r
+ shift = s_start;\r
+ sp++;\r
+ dp++;\r
+ }\r
+ else\r
+ shift += s_inc;\r
+ if (m == 1)\r
+ m = 0x80;\r
+ else\r
+ m >>= 1;\r
+ }\r
+ break;\r
+ }\r
+ default:\r
+ {\r
+ png_bytep sp = png_ptr->row_buf + 1;\r
+ png_bytep dp = row;\r
+ png_size_t pixel_bytes = (png_ptr->row_info.pixel_depth >> 3);\r
+ png_uint_32 i;\r
+ png_uint_32 row_width = png_ptr->width;\r
+ png_byte m = 0x80;\r
+\r
+\r
+ for (i = 0; i < row_width; i++)\r
+ {\r
+ if (m & mask)\r
+ {\r
+ png_memcpy(dp, sp, pixel_bytes);\r
+ }\r
+\r
+ sp += pixel_bytes;\r
+ dp += pixel_bytes;\r
+\r
+ if (m == 1)\r
+ m = 0x80;\r
+ else\r
+ m >>= 1;\r
+ }\r
+ break;\r
+ }\r
+ }\r
+ }\r
+}\r
+\r
+#ifdef PNG_READ_INTERLACING_SUPPORTED\r
+/* OLD pre-1.0.9 interface:\r
+void png_do_read_interlace(png_row_infop row_info, png_bytep row, int pass,\r
+ png_uint_32 transformations)\r
+ */\r
+void /* PRIVATE */\r
+png_do_read_interlace(png_structp png_ptr)\r
+{\r
+ png_row_infop row_info = &(png_ptr->row_info);\r
+ png_bytep row = png_ptr->row_buf + 1;\r
+ int pass = png_ptr->pass;\r
+ png_uint_32 transformations = png_ptr->transformations;\r
+#ifdef PNG_USE_LOCAL_ARRAYS\r
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */\r
+ /* offset to next interlace block */\r
+ PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};\r
+#endif\r
+\r
+ png_debug(1, "in png_do_read_interlace\n");\r
+ if (row != NULL && row_info != NULL)\r
+ {\r
+ png_uint_32 final_width;\r
+\r
+ final_width = row_info->width * png_pass_inc[pass];\r
+\r
+ switch (row_info->pixel_depth)\r
+ {\r
+ case 1:\r
+ {\r
+ png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 3);\r
+ png_bytep dp = row + (png_size_t)((final_width - 1) >> 3);\r
+ int sshift, dshift;\r
+ int s_start, s_end, s_inc;\r
+ int jstop = png_pass_inc[pass];\r
+ png_byte v;\r
+ png_uint_32 i;\r
+ int j;\r
+\r
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ if (transformations & PNG_PACKSWAP)\r
+ {\r
+ sshift = (int)((row_info->width + 7) & 0x07);\r
+ dshift = (int)((final_width + 7) & 0x07);\r
+ s_start = 7;\r
+ s_end = 0;\r
+ s_inc = -1;\r
+ }\r
+ else\r
+#endif\r
+ {\r
+ sshift = 7 - (int)((row_info->width + 7) & 0x07);\r
+ dshift = 7 - (int)((final_width + 7) & 0x07);\r
+ s_start = 0;\r
+ s_end = 7;\r
+ s_inc = 1;\r
+ }\r
+\r
+ for (i = 0; i < row_info->width; i++)\r
+ {\r
+ v = (png_byte)((*sp >> sshift) & 0x01);\r
+ for (j = 0; j < jstop; j++)\r
+ {\r
+ *dp &= (png_byte)((0x7f7f >> (7 - dshift)) & 0xff);\r
+ *dp |= (png_byte)(v << dshift);\r
+ if (dshift == s_end)\r
+ {\r
+ dshift = s_start;\r
+ dp--;\r
+ }\r
+ else\r
+ dshift += s_inc;\r
+ }\r
+ if (sshift == s_end)\r
+ {\r
+ sshift = s_start;\r
+ sp--;\r
+ }\r
+ else\r
+ sshift += s_inc;\r
+ }\r
+ break;\r
+ }\r
+ case 2:\r
+ {\r
+ png_bytep sp = row + (png_uint_32)((row_info->width - 1) >> 2);\r
+ png_bytep dp = row + (png_uint_32)((final_width - 1) >> 2);\r
+ int sshift, dshift;\r
+ int s_start, s_end, s_inc;\r
+ int jstop = png_pass_inc[pass];\r
+ png_uint_32 i;\r
+\r
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ if (transformations & PNG_PACKSWAP)\r
+ {\r
+ sshift = (int)(((row_info->width + 3) & 0x03) << 1);\r
+ dshift = (int)(((final_width + 3) & 0x03) << 1);\r
+ s_start = 6;\r
+ s_end = 0;\r
+ s_inc = -2;\r
+ }\r
+ else\r
+#endif\r
+ {\r
+ sshift = (int)((3 - ((row_info->width + 3) & 0x03)) << 1);\r
+ dshift = (int)((3 - ((final_width + 3) & 0x03)) << 1);\r
+ s_start = 0;\r
+ s_end = 6;\r
+ s_inc = 2;\r
+ }\r
+\r
+ for (i = 0; i < row_info->width; i++)\r
+ {\r
+ png_byte v;\r
+ int j;\r
+\r
+ v = (png_byte)((*sp >> sshift) & 0x03);\r
+ for (j = 0; j < jstop; j++)\r
+ {\r
+ *dp &= (png_byte)((0x3f3f >> (6 - dshift)) & 0xff);\r
+ *dp |= (png_byte)(v << dshift);\r
+ if (dshift == s_end)\r
+ {\r
+ dshift = s_start;\r
+ dp--;\r
+ }\r
+ else\r
+ dshift += s_inc;\r
+ }\r
+ if (sshift == s_end)\r
+ {\r
+ sshift = s_start;\r
+ sp--;\r
+ }\r
+ else\r
+ sshift += s_inc;\r
+ }\r
+ break;\r
+ }\r
+ case 4:\r
+ {\r
+ png_bytep sp = row + (png_size_t)((row_info->width - 1) >> 1);\r
+ png_bytep dp = row + (png_size_t)((final_width - 1) >> 1);\r
+ int sshift, dshift;\r
+ int s_start, s_end, s_inc;\r
+ png_uint_32 i;\r
+ int jstop = png_pass_inc[pass];\r
+\r
+#if defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ if (transformations & PNG_PACKSWAP)\r
+ {\r
+ sshift = (int)(((row_info->width + 1) & 0x01) << 2);\r
+ dshift = (int)(((final_width + 1) & 0x01) << 2);\r
+ s_start = 4;\r
+ s_end = 0;\r
+ s_inc = -4;\r
+ }\r
+ else\r
+#endif\r
+ {\r
+ sshift = (int)((1 - ((row_info->width + 1) & 0x01)) << 2);\r
+ dshift = (int)((1 - ((final_width + 1) & 0x01)) << 2);\r
+ s_start = 0;\r
+ s_end = 4;\r
+ s_inc = 4;\r
+ }\r
+\r
+ for (i = 0; i < row_info->width; i++)\r
+ {\r
+ png_byte v = (png_byte)((*sp >> sshift) & 0xf);\r
+ int j;\r
+\r
+ for (j = 0; j < jstop; j++)\r
+ {\r
+ *dp &= (png_byte)((0xf0f >> (4 - dshift)) & 0xff);\r
+ *dp |= (png_byte)(v << dshift);\r
+ if (dshift == s_end)\r
+ {\r
+ dshift = s_start;\r
+ dp--;\r
+ }\r
+ else\r
+ dshift += s_inc;\r
+ }\r
+ if (sshift == s_end)\r
+ {\r
+ sshift = s_start;\r
+ sp--;\r
+ }\r
+ else\r
+ sshift += s_inc;\r
+ }\r
+ break;\r
+ }\r
+ default:\r
+ {\r
+ png_size_t pixel_bytes = (row_info->pixel_depth >> 3);\r
+ png_bytep sp = row + (png_size_t)(row_info->width - 1) * pixel_bytes;\r
+ png_bytep dp = row + (png_size_t)(final_width - 1) * pixel_bytes;\r
+\r
+ int jstop = png_pass_inc[pass];\r
+ png_uint_32 i;\r
+\r
+ for (i = 0; i < row_info->width; i++)\r
+ {\r
+ png_byte v[8];\r
+ int j;\r
+\r
+ png_memcpy(v, sp, pixel_bytes);\r
+ for (j = 0; j < jstop; j++)\r
+ {\r
+ png_memcpy(dp, v, pixel_bytes);\r
+ dp -= pixel_bytes;\r
+ }\r
+ sp -= pixel_bytes;\r
+ }\r
+ break;\r
+ }\r
+ }\r
+ row_info->width = final_width;\r
+ row_info->rowbytes = PNG_ROWBYTES(row_info->pixel_depth, final_width);\r
+ }\r
+#if !defined(PNG_READ_PACKSWAP_SUPPORTED)\r
+ transformations = transformations; /* silence compiler warning */\r
+#endif\r
+}\r
+#endif /* PNG_READ_INTERLACING_SUPPORTED */\r
+\r
+void /* PRIVATE */\r
+png_read_filter_row(png_structp png_ptr, png_row_infop row_info, png_bytep row,\r
+ png_bytep prev_row, int filter)\r
+{\r
+ png_debug(1, "in png_read_filter_row\n");\r
+ png_debug2(2, "row = %lu, filter = %d\n", png_ptr->row_number, filter);\r
+ switch (filter)\r
+ {\r
+ case PNG_FILTER_VALUE_NONE:\r
+ break;\r
+ case PNG_FILTER_VALUE_SUB:\r
+ {\r
+ png_uint_32 i;\r
+ png_uint_32 istop = row_info->rowbytes;\r
+ png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;\r
+ png_bytep rp = row + bpp;\r
+ png_bytep lp = row;\r
+\r
+ for (i = bpp; i < istop; i++)\r
+ {\r
+ *rp = (png_byte)(((int)(*rp) + (int)(*lp++)) & 0xff);\r
+ rp++;\r
+ }\r
+ break;\r
+ }\r
+ case PNG_FILTER_VALUE_UP:\r
+ {\r
+ png_uint_32 i;\r
+ png_uint_32 istop = row_info->rowbytes;\r
+ png_bytep rp = row;\r
+ png_bytep pp = prev_row;\r
+\r
+ for (i = 0; i < istop; i++)\r
+ {\r
+ *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);\r
+ rp++;\r
+ }\r
+ break;\r
+ }\r
+ case PNG_FILTER_VALUE_AVG:\r
+ {\r
+ png_uint_32 i;\r
+ png_bytep rp = row;\r
+ png_bytep pp = prev_row;\r
+ png_bytep lp = row;\r
+ png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;\r
+ png_uint_32 istop = row_info->rowbytes - bpp;\r
+\r
+ for (i = 0; i < bpp; i++)\r
+ {\r
+ *rp = (png_byte)(((int)(*rp) +\r
+ ((int)(*pp++) / 2 )) & 0xff);\r
+ rp++;\r
+ }\r
+\r
+ for (i = 0; i < istop; i++)\r
+ {\r
+ *rp = (png_byte)(((int)(*rp) +\r
+ (int)(*pp++ + *lp++) / 2 ) & 0xff);\r
+ rp++;\r
+ }\r
+ break;\r
+ }\r
+ case PNG_FILTER_VALUE_PAETH:\r
+ {\r
+ png_uint_32 i;\r
+ png_bytep rp = row;\r
+ png_bytep pp = prev_row;\r
+ png_bytep lp = row;\r
+ png_bytep cp = prev_row;\r
+ png_uint_32 bpp = (row_info->pixel_depth + 7) >> 3;\r
+ png_uint_32 istop=row_info->rowbytes - bpp;\r
+\r
+ for (i = 0; i < bpp; i++)\r
+ {\r
+ *rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);\r
+ rp++;\r
+ }\r
+\r
+ for (i = 0; i < istop; i++) /* use leftover rp,pp */\r
+ {\r
+ int a, b, c, pa, pb, pc, p;\r
+\r
+ a = *lp++;\r
+ b = *pp++;\r
+ c = *cp++;\r
+\r
+ p = b - c;\r
+ pc = a - c;\r
+\r
+#ifdef PNG_USE_ABS\r
+ pa = abs(p);\r
+ pb = abs(pc);\r
+ pc = abs(p + pc);\r
+#else\r
+ pa = p < 0 ? -p : p;\r
+ pb = pc < 0 ? -pc : pc;\r
+ pc = (p + pc) < 0 ? -(p + pc) : p + pc;\r
+#endif\r
+\r
+ /*\r
+ if (pa <= pb && pa <= pc)\r
+ p = a;\r
+ else if (pb <= pc)\r
+ p = b;\r
+ else\r
+ p = c;\r
+ */\r
+\r
+ p = (pa <= pb && pa <= pc) ? a : (pb <= pc) ? b : c;\r
+\r
+ *rp = (png_byte)(((int)(*rp) + p) & 0xff);\r
+ rp++;\r
+ }\r
+ break;\r
+ }\r
+ default:\r
+ png_warning(png_ptr, "Ignoring bad adaptive filter type");\r
+ *row = 0;\r
+ break;\r
+ }\r
+}\r
+\r
+void /* PRIVATE */\r
+png_read_finish_row(png_structp png_ptr)\r
+{\r
+#ifdef PNG_USE_LOCAL_ARRAYS\r
+#ifdef PNG_READ_INTERLACING_SUPPORTED\r
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */\r
+\r
+ /* start of interlace block */\r
+ PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};\r
+\r
+ /* offset to next interlace block */\r
+ PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};\r
+\r
+ /* start of interlace block in the y direction */\r
+ PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};\r
+\r
+ /* offset to next interlace block in the y direction */\r
+ PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};\r
+#endif /* PNG_READ_INTERLACING_SUPPORTED */\r
+#endif\r
+\r
+ png_debug(1, "in png_read_finish_row\n");\r
+ png_ptr->row_number++;\r
+ if (png_ptr->row_number < png_ptr->num_rows)\r
+ return;\r
+\r
+#ifdef PNG_READ_INTERLACING_SUPPORTED\r
+ if (png_ptr->interlaced)\r
+ {\r
+ png_ptr->row_number = 0;\r
+ png_memset_check(png_ptr, png_ptr->prev_row, 0,\r
+ png_ptr->rowbytes + 1);\r
+ do\r
+ {\r
+ png_ptr->pass++;\r
+ if (png_ptr->pass >= 7)\r
+ break;\r
+ png_ptr->iwidth = (png_ptr->width +\r
+ png_pass_inc[png_ptr->pass] - 1 -\r
+ png_pass_start[png_ptr->pass]) /\r
+ png_pass_inc[png_ptr->pass];\r
+\r
+ png_ptr->irowbytes = PNG_ROWBYTES(png_ptr->pixel_depth,\r
+ png_ptr->iwidth) + 1;\r
+\r
+ if (!(png_ptr->transformations & PNG_INTERLACE))\r
+ {\r
+ png_ptr->num_rows = (png_ptr->height +\r
+ png_pass_yinc[png_ptr->pass] - 1 -\r
+ png_pass_ystart[png_ptr->pass]) /\r
+ png_pass_yinc[png_ptr->pass];\r
+ if (!(png_ptr->num_rows))\r
+ continue;\r
+ }\r
+ else /* if (png_ptr->transformations & PNG_INTERLACE) */\r
+ break;\r
+ } while (png_ptr->iwidth == 0);\r
+\r
+ if (png_ptr->pass < 7)\r
+ return;\r
+ }\r
+#endif /* PNG_READ_INTERLACING_SUPPORTED */\r
+\r
+ if (!(png_ptr->flags & PNG_FLAG_ZLIB_FINISHED))\r
+ {\r
+#ifdef PNG_USE_LOCAL_ARRAYS\r
+ PNG_CONST PNG_IDAT;\r
+#endif\r
+ char extra;\r
+ int ret;\r
+\r
+ png_ptr->zstream.next_out = (Byte *)&extra;\r
+ png_ptr->zstream.avail_out = (uInt)1;\r
+ for (;;)\r
+ {\r
+ if (!(png_ptr->zstream.avail_in))\r
+ {\r
+ while (!png_ptr->idat_size)\r
+ {\r
+ png_byte chunk_length[4];\r
+\r
+ png_crc_finish(png_ptr, 0);\r
+\r
+ png_read_data(png_ptr, chunk_length, 4);\r
+ png_ptr->idat_size = png_get_uint_31(png_ptr, chunk_length);\r
+ png_reset_crc(png_ptr);\r
+ png_crc_read(png_ptr, png_ptr->chunk_name, 4);\r
+ if (png_memcmp(png_ptr->chunk_name, png_IDAT, 4))\r
+ png_error(png_ptr, "Not enough image data");\r
+\r
+ }\r
+ png_ptr->zstream.avail_in = (uInt)png_ptr->zbuf_size;\r
+ png_ptr->zstream.next_in = png_ptr->zbuf;\r
+ if (png_ptr->zbuf_size > png_ptr->idat_size)\r
+ png_ptr->zstream.avail_in = (uInt)png_ptr->idat_size;\r
+ png_crc_read(png_ptr, png_ptr->zbuf, png_ptr->zstream.avail_in);\r
+ png_ptr->idat_size -= png_ptr->zstream.avail_in;\r
+ }\r
+ ret = inflate(&png_ptr->zstream, Z_PARTIAL_FLUSH);\r
+ if (ret == Z_STREAM_END)\r
+ {\r
+ if (!(png_ptr->zstream.avail_out) || png_ptr->zstream.avail_in ||\r
+ png_ptr->idat_size)\r
+ png_warning(png_ptr, "Extra compressed data");\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;\r
+ break;\r
+ }\r
+ if (ret != Z_OK)\r
+ png_error(png_ptr, png_ptr->zstream.msg ? png_ptr->zstream.msg :\r
+ "Decompression Error");\r
+\r
+ if (!(png_ptr->zstream.avail_out))\r
+ {\r
+ png_warning(png_ptr, "Extra compressed data.");\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+ png_ptr->flags |= PNG_FLAG_ZLIB_FINISHED;\r
+ break;\r
+ }\r
+\r
+ }\r
+ png_ptr->zstream.avail_out = 0;\r
+ }\r
+\r
+ if (png_ptr->idat_size || png_ptr->zstream.avail_in)\r
+ png_warning(png_ptr, "Extra compression data");\r
+\r
+ inflateReset(&png_ptr->zstream);\r
+\r
+ png_ptr->mode |= PNG_AFTER_IDAT;\r
+}\r
+\r
+void /* PRIVATE */\r
+png_read_start_row(png_structp png_ptr)\r
+{\r
+#ifdef PNG_USE_LOCAL_ARRAYS\r
+#ifdef PNG_READ_INTERLACING_SUPPORTED\r
+ /* arrays to facilitate easy interlacing - use pass (0 - 6) as index */\r
+\r
+ /* start of interlace block */\r
+ PNG_CONST int png_pass_start[7] = {0, 4, 0, 2, 0, 1, 0};\r
+\r
+ /* offset to next interlace block */\r
+ PNG_CONST int png_pass_inc[7] = {8, 8, 4, 4, 2, 2, 1};\r
+\r
+ /* start of interlace block in the y direction */\r
+ PNG_CONST int png_pass_ystart[7] = {0, 0, 4, 0, 2, 0, 1};\r
+\r
+ /* offset to next interlace block in the y direction */\r
+ PNG_CONST int png_pass_yinc[7] = {8, 8, 8, 4, 4, 2, 2};\r
+#endif\r
+#endif\r
+\r
+ int max_pixel_depth;\r
+ png_size_t row_bytes;\r
+\r
+ png_debug(1, "in png_read_start_row\n");\r
+ png_ptr->zstream.avail_in = 0;\r
+ png_init_read_transformations(png_ptr);\r
+#ifdef PNG_READ_INTERLACING_SUPPORTED\r
+ if (png_ptr->interlaced)\r
+ {\r
+ if (!(png_ptr->transformations & PNG_INTERLACE))\r
+ png_ptr->num_rows = (png_ptr->height + png_pass_yinc[0] - 1 -\r
+ png_pass_ystart[0]) / png_pass_yinc[0];\r
+ else\r
+ png_ptr->num_rows = png_ptr->height;\r
+\r
+ png_ptr->iwidth = (png_ptr->width +\r
+ png_pass_inc[png_ptr->pass] - 1 -\r
+ png_pass_start[png_ptr->pass]) /\r
+ png_pass_inc[png_ptr->pass];\r
+\r
+ png_ptr->irowbytes =\r
+ PNG_ROWBYTES(png_ptr->pixel_depth, png_ptr->iwidth) + 1;\r
+ }\r
+ else\r
+#endif /* PNG_READ_INTERLACING_SUPPORTED */\r
+ {\r
+ png_ptr->num_rows = png_ptr->height;\r
+ png_ptr->iwidth = png_ptr->width;\r
+ png_ptr->irowbytes = png_ptr->rowbytes + 1;\r
+ }\r
+ max_pixel_depth = png_ptr->pixel_depth;\r
+\r
+#if defined(PNG_READ_PACK_SUPPORTED)\r
+ if ((png_ptr->transformations & PNG_PACK) && png_ptr->bit_depth < 8)\r
+ max_pixel_depth = 8;\r
+#endif\r
+\r
+#if defined(PNG_READ_EXPAND_SUPPORTED)\r
+ if (png_ptr->transformations & PNG_EXPAND)\r
+ {\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ {\r
+ if (png_ptr->num_trans)\r
+ max_pixel_depth = 32;\r
+ else\r
+ max_pixel_depth = 24;\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)\r
+ {\r
+ if (max_pixel_depth < 8)\r
+ max_pixel_depth = 8;\r
+ if (png_ptr->num_trans)\r
+ max_pixel_depth *= 2;\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)\r
+ {\r
+ if (png_ptr->num_trans)\r
+ {\r
+ max_pixel_depth *= 4;\r
+ max_pixel_depth /= 3;\r
+ }\r
+ }\r
+ }\r
+#endif\r
+\r
+#if defined(PNG_READ_FILLER_SUPPORTED)\r
+ if (png_ptr->transformations & (PNG_FILLER))\r
+ {\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)\r
+ max_pixel_depth = 32;\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_GRAY)\r
+ {\r
+ if (max_pixel_depth <= 8)\r
+ max_pixel_depth = 16;\r
+ else\r
+ max_pixel_depth = 32;\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)\r
+ {\r
+ if (max_pixel_depth <= 32)\r
+ max_pixel_depth = 32;\r
+ else\r
+ max_pixel_depth = 64;\r
+ }\r
+ }\r
+#endif\r
+\r
+#if defined(PNG_READ_GRAY_TO_RGB_SUPPORTED)\r
+ if (png_ptr->transformations & PNG_GRAY_TO_RGB)\r
+ {\r
+ if (\r
+#if defined(PNG_READ_EXPAND_SUPPORTED)\r
+ (png_ptr->num_trans && (png_ptr->transformations & PNG_EXPAND)) ||\r
+#endif\r
+#if defined(PNG_READ_FILLER_SUPPORTED)\r
+ (png_ptr->transformations & (PNG_FILLER)) ||\r
+#endif\r
+ png_ptr->color_type == PNG_COLOR_TYPE_GRAY_ALPHA)\r
+ {\r
+ if (max_pixel_depth <= 16)\r
+ max_pixel_depth = 32;\r
+ else\r
+ max_pixel_depth = 64;\r
+ }\r
+ else\r
+ {\r
+ if (max_pixel_depth <= 8)\r
+ {\r
+ if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)\r
+ max_pixel_depth = 32;\r
+ else\r
+ max_pixel_depth = 24;\r
+ }\r
+ else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)\r
+ max_pixel_depth = 64;\r
+ else\r
+ max_pixel_depth = 48;\r
+ }\r
+ }\r
+#endif\r
+\r
+#if defined(PNG_READ_USER_TRANSFORM_SUPPORTED) && \\r
+defined(PNG_USER_TRANSFORM_PTR_SUPPORTED)\r
+ if (png_ptr->transformations & PNG_USER_TRANSFORM)\r
+ {\r
+ int user_pixel_depth = png_ptr->user_transform_depth*\r
+ png_ptr->user_transform_channels;\r
+ if (user_pixel_depth > max_pixel_depth)\r
+ max_pixel_depth=user_pixel_depth;\r
+ }\r
+#endif\r
+\r
+ /* align the width on the next larger 8 pixels. Mainly used\r
+ for interlacing */\r
+ row_bytes = ((png_ptr->width + 7) & ~((png_uint_32)7));\r
+ /* calculate the maximum bytes needed, adding a byte and a pixel\r
+ for safety's sake */\r
+ row_bytes = PNG_ROWBYTES(max_pixel_depth, row_bytes) +\r
+ 1 + ((max_pixel_depth + 7) >> 3);\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ if (row_bytes > (png_uint_32)65536L)\r
+ png_error(png_ptr, "This image requires a row greater than 64KB");\r
+#endif\r
+\r
+ if (row_bytes + 64 > png_ptr->old_big_row_buf_size)\r
+ {\r
+ png_free(png_ptr, png_ptr->big_row_buf);\r
+ png_ptr->big_row_buf = (png_bytep)png_malloc(png_ptr, row_bytes+64);\r
+ png_ptr->row_buf = png_ptr->big_row_buf+32;\r
+ png_ptr->old_big_row_buf_size = row_bytes+64;\r
+ }\r
+\r
+#ifdef PNG_MAX_MALLOC_64K\r
+ if ((png_uint_32)png_ptr->rowbytes + 1 > (png_uint_32)65536L)\r
+ png_error(png_ptr, "This image requires a row greater than 64KB");\r
+#endif\r
+ if ((png_uint_32)png_ptr->rowbytes > (png_uint_32)(PNG_SIZE_MAX - 1))\r
+ png_error(png_ptr, "Row has too many bytes to allocate in memory.");\r
+\r
+ if (png_ptr->rowbytes+1 > png_ptr->old_prev_row_size)\r
+ {\r
+ png_free(png_ptr, png_ptr->prev_row);\r
+ png_ptr->prev_row = (png_bytep)png_malloc(png_ptr, (png_uint_32)(\r
+ png_ptr->rowbytes + 1));\r
+ png_ptr->old_prev_row_size = png_ptr->rowbytes+1;\r
+ }\r
+\r
+ png_memset_check(png_ptr, png_ptr->prev_row, 0, png_ptr->rowbytes + 1);\r
+\r
+ png_debug1(3, "width = %lu,\n", png_ptr->width);\r
+ png_debug1(3, "height = %lu,\n", png_ptr->height);\r
+ png_debug1(3, "iwidth = %lu,\n", png_ptr->iwidth);\r
+ png_debug1(3, "num_rows = %lu\n", png_ptr->num_rows);\r
+ png_debug1(3, "rowbytes = %lu,\n", png_ptr->rowbytes);\r
+ png_debug1(3, "irowbytes = %lu,\n", png_ptr->irowbytes);\r
+\r
+ png_ptr->flags |= PNG_FLAG_ROW_INIT;\r
+}\r
+#endif /* PNG_READ_SUPPORTED */\r
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