/* * GStreamer * Copyright 2007 Edgard Lima * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER * DEALINGS IN THE SOFTWARE. * * Alternatively, the contents of this file may be used under the * GNU Lesser General Public License Version 2.1 (the "LGPL"), in * which case the following provisions apply instead of the ones * mentioned above: * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #include "metadataparsepng.h" #include static MetadataParsingReturn metadataparse_png_reading (PngParseData * png_data, guint8 ** buf, guint32 * bufsize, const guint32 offset, const guint8 * step_buf, guint8 ** next_start, guint32 * next_size); static MetadataParsingReturn metadataparse_png_xmp (PngParseData * png_data, guint8 ** buf, guint32 * bufsize, guint8 ** next_start, guint32 * next_size); static MetadataParsingReturn metadataparse_png_jump (PngParseData * png_data, guint8 ** buf, guint32 * bufsize, guint8 ** next_start, guint32 * next_size); #define READ(buf, size) ( (size)--, *((buf)++) ) void metadataparse_png_lazy_update (PngParseData * jpeg_data) { /* nothing to do */ } void metadataparse_png_init (PngParseData * png_data, GstAdapter ** exif_adpt, GstAdapter ** iptc_adpt, GstAdapter ** xmp_adpt, MetadataChunkArray * strip_chunks, MetadataChunkArray * inject_chunks, gboolean parse_only) { png_data->state = PNG_PARSE_NULL; png_data->xmp_adapter = xmp_adpt; png_data->read = 0; png_data->strip_chunks = strip_chunks; png_data->parse_only = parse_only; } void metadataparse_png_dispose (PngParseData * png_data) { png_data->xmp_adapter = NULL; } MetadataParsingReturn metadataparse_png_parse (PngParseData * png_data, guint8 * buf, guint32 * bufsize, const guint32 offset, guint8 ** next_start, guint32 * next_size) { int ret = META_PARSING_DONE; guint8 mark[8]; const guint8 *step_buf = buf; *next_start = buf; if (png_data->state == PNG_PARSE_NULL) { if (*bufsize < 8) { *next_size = (buf - *next_start) + 8; ret = META_PARSING_NEED_MORE_DATA; goto done; } mark[0] = READ (buf, *bufsize); mark[1] = READ (buf, *bufsize); mark[2] = READ (buf, *bufsize); mark[3] = READ (buf, *bufsize); mark[4] = READ (buf, *bufsize); mark[5] = READ (buf, *bufsize); mark[6] = READ (buf, *bufsize); mark[7] = READ (buf, *bufsize); if (mark[0] != 0x89 || mark[1] != 0x50 || mark[2] != 0x4E || mark[3] != 0x47 || mark[4] != 0x0D || mark[5] != 0x0A || mark[6] != 0x1A || mark[7] != 0x0A) { ret = META_PARSING_ERROR; goto done; } png_data->state = PNG_PARSE_READING; } while (ret == META_PARSING_DONE) { switch (png_data->state) { case PNG_PARSE_READING: ret = metadataparse_png_reading (png_data, &buf, bufsize, offset, step_buf, next_start, next_size); break; case PNG_PARSE_JUMPING: ret = metadataparse_png_jump (png_data, &buf, bufsize, next_start, next_size); break; case PNG_PARSE_XMP: ret = metadataparse_png_xmp (png_data, &buf, bufsize, next_start, next_size); break; case PNG_PARSE_DONE: goto done; break; default: ret = META_PARSING_ERROR; break; } } done: return ret; } /* look for markers */ static MetadataParsingReturn metadataparse_png_reading (PngParseData * png_data, guint8 ** buf, guint32 * bufsize, const guint32 offset, const guint8 * step_buf, guint8 ** next_start, guint32 * next_size) { int ret = META_PARSING_ERROR; guint8 mark[4]; guint32 chunk_size = 0; static const char XmpHeader[] = "XML:com.adobe.xmp"; *next_start = *buf; if (*bufsize < 8) { *next_size = (*buf - *next_start) + 8; ret = META_PARSING_NEED_MORE_DATA; goto done; } chunk_size = READ (*buf, *bufsize) << 24; chunk_size += READ (*buf, *bufsize) << 16; chunk_size += READ (*buf, *bufsize) << 8; chunk_size += READ (*buf, *bufsize); mark[0] = READ (*buf, *bufsize); mark[1] = READ (*buf, *bufsize); mark[2] = READ (*buf, *bufsize); mark[3] = READ (*buf, *bufsize); if (mark[0] == 'I' && mark[1] == 'E' && mark[2] == 'N' && mark[3] == 'D') { ret = META_PARSING_DONE; png_data->state = PNG_PARSE_DONE; goto done; } if (mark[0] == 'i' && mark[1] == 'T' && mark[2] == 'X' && mark[3] == 't') { if (chunk_size >= 22) { /* "XML:com.adobe.xmp" plus some flags */ if (*bufsize < 22) { *next_size = (*buf - *next_start) + 22; ret = META_PARSING_NEED_MORE_DATA; goto done; } if (0 == memcmp (XmpHeader, *buf, 18)) { if (!png_data->parse_only) { MetadataChunk chunk; memset (&chunk, 0x00, sizeof (MetadataChunk)); chunk.offset_orig = (*buf - step_buf) + offset - 8; /* maker + size */ chunk.size = chunk_size + 12; /* chunk size plus app marker plus crc */ chunk.type = MD_CHUNK_XMP; metadata_chunk_array_append_sorted (png_data->strip_chunks, &chunk); } /* if adapter has been provided, prepare to hold chunk */ if (png_data->xmp_adapter) { *buf += 22; /* jump "XML:com.adobe.xmp" plus some flags */ *bufsize -= 22; png_data->read = chunk_size - 22; /* four CRC bytes at the end will be jumped after */ png_data->state = PNG_PARSE_XMP; ret = META_PARSING_DONE; goto done; } } } } /* just set jump sise */ png_data->read = chunk_size + 4; /* four CRC bytes at the end */ png_data->state = PNG_PARSE_JUMPING; ret = META_PARSING_DONE; done: return ret; } static MetadataParsingReturn metadataparse_png_jump (PngParseData * png_data, guint8 ** buf, guint32 * bufsize, guint8 ** next_start, guint32 * next_size) { png_data->state = PNG_PARSE_READING; return metadataparse_util_jump_chunk (&png_data->read, buf, bufsize, next_start, next_size); } static MetadataParsingReturn metadataparse_png_xmp (PngParseData * png_data, guint8 ** buf, guint32 * bufsize, guint8 ** next_start, guint32 * next_size) { int ret; ret = metadataparse_util_hold_chunk (&png_data->read, buf, bufsize, next_start, next_size, png_data->xmp_adapter); if (ret == META_PARSING_DONE) { /* jump four CRC bytes at the end of chunk */ png_data->read = 4; png_data->state = PNG_PARSE_JUMPING; /* if there is a second XMP chunk in the file it will be jumped */ png_data->xmp_adapter = NULL; } return ret; }