diff options
Diffstat (limited to '')
| -rw-r--r-- | src/decoder/flac_metadata.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/src/decoder/flac_metadata.c b/src/decoder/flac_metadata.c new file mode 100644 index 000000000..912559c8d --- /dev/null +++ b/src/decoder/flac_metadata.c @@ -0,0 +1,192 @@ +/* + * Copyright (C) 2003-2009 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 "flac_metadata.h" +#include "replay_gain.h" +#include "tag.h" + +#include <glib.h> + +#include <assert.h> +#include <stdbool.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; +} + +struct replay_gain_info * +flac_parse_replay_gain(const FLAC__StreamMetadata *block) +{ + struct replay_gain_info *rgi; + bool found = false; + + rgi = replay_gain_info_new(); + + found = flac_find_float_comment(block, "replaygain_album_gain", + &rgi->tuples[REPLAY_GAIN_ALBUM].gain) || + flac_find_float_comment(block, "replaygain_album_peak", + &rgi->tuples[REPLAY_GAIN_ALBUM].peak) || + flac_find_float_comment(block, "replaygain_track_gain", + &rgi->tuples[REPLAY_GAIN_TRACK].gain) || + flac_find_float_comment(block, "replaygain_track_peak", + &rgi->tuples[REPLAY_GAIN_TRACK].peak); + if (!found) { + replay_gain_info_free(rgi); + rgi = NULL; + } + + return rgi; +} + +/** + * 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, const char *char_tnum, size_t *length_r) +{ + size_t name_length = strlen(name); + size_t char_tnum_length = 0; + const char *comment = (const char*)entry->entry; + + if (entry->length <= name_length || + g_ascii_strncasecmp(comment, name, name_length) != 0) + return NULL; + + if (char_tnum != NULL) { + char_tnum_length = strlen(char_tnum); + if (entry->length > name_length + char_tnum_length + 2 && + comment[name_length] == '[' && + g_ascii_strncasecmp(comment + name_length + 1, + char_tnum, char_tnum_length) == 0 && + comment[name_length + char_tnum_length + 1] == ']') + name_length = name_length + char_tnum_length + 2; + else if (entry->length > name_length + char_tnum_length && + g_ascii_strncasecmp(comment + name_length, + char_tnum, char_tnum_length) == 0) + name_length = name_length + char_tnum_length; + } + + if (comment[name_length] == '=') { + *length_r = entry->length - name_length - 1; + return comment + name_length + 1; + } + + return NULL; +} + +/** + * 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(struct tag *tag, + const FLAC__StreamMetadata_VorbisComment_Entry *entry, + const char *name, enum tag_type tag_type, + const char *char_tnum) +{ + const char *value; + size_t value_length; + + value = flac_comment_value(entry, name, char_tnum, &value_length); + if (value != NULL) { + tag_add_item_n(tag, tag_type, value, value_length); + return true; + } + + return false; +} + +/* tracknumber is used in VCs, MPD uses "track" ..., all the other + * tag names match */ +static const char *VORBIS_COMMENT_TRACK_KEY = "tracknumber"; +static const char *VORBIS_COMMENT_DISC_KEY = "discnumber"; + +static void +flac_parse_comment(struct tag *tag, const char *char_tnum, + const FLAC__StreamMetadata_VorbisComment_Entry *entry) +{ + assert(tag != NULL); + + if (flac_copy_comment(tag, entry, VORBIS_COMMENT_TRACK_KEY, + TAG_TRACK, char_tnum) || + flac_copy_comment(tag, entry, VORBIS_COMMENT_DISC_KEY, + TAG_DISC, char_tnum) || + flac_copy_comment(tag, entry, "album artist", + TAG_ALBUM_ARTIST, char_tnum)) + return; + + for (unsigned i = 0; i < TAG_NUM_OF_ITEM_TYPES; ++i) + if (flac_copy_comment(tag, entry, + tag_item_names[i], i, char_tnum)) + return; +} + +void +flac_vorbis_comments_to_tag(struct tag *tag, const char *char_tnum, + const FLAC__StreamMetadata_VorbisComment *comment) +{ + for (unsigned i = 0; i < comment->num_comments; ++i) + flac_parse_comment(tag, char_tnum, &comment->comments[i]); +} + +void +flac_tag_apply_metadata(struct tag *tag, const char *track, + const FLAC__StreamMetadata *block) +{ + switch (block->type) { + case FLAC__METADATA_TYPE_VORBIS_COMMENT: + flac_vorbis_comments_to_tag(tag, track, + &block->data.vorbis_comment); + break; + + case FLAC__METADATA_TYPE_STREAMINFO: + tag->time = flac_duration(&block->data.stream_info); + break; + + default: + break; + } +} |