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Diffstat (limited to '')
| -rw-r--r-- | src/decoder/FLACMetaData.cxx | 253 |
1 files changed, 253 insertions, 0 deletions
diff --git a/src/decoder/FLACMetaData.cxx b/src/decoder/FLACMetaData.cxx new file mode 100644 index 000000000..8273a230b --- /dev/null +++ b/src/decoder/FLACMetaData.cxx @@ -0,0 +1,253 @@ +/* + * Copyright (C) 2003-2012 The Music Player Daemon Project + * http://www.musicpd.org + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "config.h" +#include "FLACMetaData.hxx" + +extern "C" { +#include "XiphTags.h" +} + +#include "tag.h" +#include "tag_handler.h" +#include "tag_table.h" +#include "replay_gain_info.h" + +#include <glib.h> + +#include <assert.h> +#include <stdlib.h> + +static bool +flac_find_float_comment(const FLAC__StreamMetadata *block, + const char *cmnt, float *fl) +{ + int offset; + size_t pos; + int len; + unsigned char tmp, *p; + + offset = FLAC__metadata_object_vorbiscomment_find_entry_from(block, 0, + cmnt); + if (offset < 0) + return false; + + pos = strlen(cmnt) + 1; /* 1 is for '=' */ + len = block->data.vorbis_comment.comments[offset].length - pos; + if (len <= 0) + return false; + + p = &block->data.vorbis_comment.comments[offset].entry[pos]; + tmp = p[len]; + p[len] = '\0'; + *fl = (float)atof((char *)p); + p[len] = tmp; + + return true; +} + +bool +flac_parse_replay_gain(struct replay_gain_info *rgi, + const FLAC__StreamMetadata *block) +{ + bool found = false; + + replay_gain_info_init(rgi); + + if (flac_find_float_comment(block, "replaygain_album_gain", + &rgi->tuples[REPLAY_GAIN_ALBUM].gain)) + found = true; + if (flac_find_float_comment(block, "replaygain_album_peak", + &rgi->tuples[REPLAY_GAIN_ALBUM].peak)) + found = true; + if (flac_find_float_comment(block, "replaygain_track_gain", + &rgi->tuples[REPLAY_GAIN_TRACK].gain)) + found = true; + if (flac_find_float_comment(block, "replaygain_track_peak", + &rgi->tuples[REPLAY_GAIN_TRACK].peak)) + found = true; + + return found; +} + +static bool +flac_find_string_comment(const FLAC__StreamMetadata *block, + const char *cmnt, char **str) +{ + int offset; + size_t pos; + int len; + const unsigned char *p; + + *str = nullptr; + offset = FLAC__metadata_object_vorbiscomment_find_entry_from(block, 0, + cmnt); + if (offset < 0) + return false; + + pos = strlen(cmnt) + 1; /* 1 is for '=' */ + len = block->data.vorbis_comment.comments[offset].length - pos; + if (len <= 0) + return false; + + p = &block->data.vorbis_comment.comments[offset].entry[pos]; + *str = g_strndup((const char *)p, len); + + return true; +} + +bool +flac_parse_mixramp(char **mixramp_start, char **mixramp_end, + const FLAC__StreamMetadata *block) +{ + bool found = false; + + if (flac_find_string_comment(block, "mixramp_start", mixramp_start)) + found = true; + if (flac_find_string_comment(block, "mixramp_end", mixramp_end)) + found = true; + + return found; +} + +/** + * Checks if the specified name matches the entry's name, and if yes, + * returns the comment value (not null-temrinated). + */ +static const char * +flac_comment_value(const FLAC__StreamMetadata_VorbisComment_Entry *entry, + const char *name, size_t *length_r) +{ + size_t name_length = strlen(name); + const char *comment = (const char*)entry->entry; + + if (entry->length <= name_length || + g_ascii_strncasecmp(comment, name, name_length) != 0) + return nullptr; + + if (comment[name_length] == '=') { + *length_r = entry->length - name_length - 1; + return comment + name_length + 1; + } + + return nullptr; +} + +/** + * Check if the comment's name equals the passed name, and if so, copy + * the comment value into the tag. + */ +static bool +flac_copy_comment(const FLAC__StreamMetadata_VorbisComment_Entry *entry, + const char *name, enum tag_type tag_type, + const struct tag_handler *handler, void *handler_ctx) +{ + const char *value; + size_t value_length; + + value = flac_comment_value(entry, name, &value_length); + if (value != nullptr) { + char *p = g_strndup(value, value_length); + tag_handler_invoke_tag(handler, handler_ctx, tag_type, p); + g_free(p); + return true; + } + + return false; +} + +static void +flac_scan_comment(const FLAC__StreamMetadata_VorbisComment_Entry *entry, + const struct tag_handler *handler, void *handler_ctx) +{ + if (handler->pair != nullptr) { + char *name = g_strdup((const char*)entry->entry); + char *value = strchr(name, '='); + + if (value != nullptr && value > name) { + *value++ = 0; + tag_handler_invoke_pair(handler, handler_ctx, + name, value); + } + + g_free(name); + } + + for (const struct tag_table *i = xiph_tags; i->name != nullptr; ++i) + if (flac_copy_comment(entry, i->name, i->type, + handler, handler_ctx)) + return; + + for (unsigned i = 0; i < TAG_NUM_OF_ITEM_TYPES; ++i) + if (flac_copy_comment(entry, + tag_item_names[i], (enum tag_type)i, + handler, handler_ctx)) + return; +} + +static void +flac_scan_comments(const FLAC__StreamMetadata_VorbisComment *comment, + const struct tag_handler *handler, void *handler_ctx) +{ + for (unsigned i = 0; i < comment->num_comments; ++i) + flac_scan_comment(&comment->comments[i], + handler, handler_ctx); +} + +void +flac_scan_metadata(const FLAC__StreamMetadata *block, + const struct tag_handler *handler, void *handler_ctx) +{ + switch (block->type) { + case FLAC__METADATA_TYPE_VORBIS_COMMENT: + flac_scan_comments(&block->data.vorbis_comment, + handler, handler_ctx); + break; + + case FLAC__METADATA_TYPE_STREAMINFO: + if (block->data.stream_info.sample_rate > 0) + tag_handler_invoke_duration(handler, handler_ctx, + flac_duration(&block->data.stream_info)); + break; + + default: + break; + } +} + +void +flac_vorbis_comments_to_tag(struct tag *tag, + const FLAC__StreamMetadata_VorbisComment *comment) +{ + flac_scan_comments(comment, &add_tag_handler, tag); +} + +void +FLACMetadataChain::Scan(const struct tag_handler *handler, void *handler_ctx) +{ + FLACMetadataIterator iterator(*this); + + do { + FLAC__StreamMetadata *block = iterator.GetBlock(); + if (block == nullptr) + break; + + flac_scan_metadata(block, handler, handler_ctx); + } while (iterator.Next()); +} |