diff options
Diffstat (limited to 'src/decoder/plugins/FlacMetadata.cxx')
| -rw-r--r-- | src/decoder/plugins/FlacMetadata.cxx | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/src/decoder/plugins/FlacMetadata.cxx b/src/decoder/plugins/FlacMetadata.cxx new file mode 100644 index 000000000..b921e8481 --- /dev/null +++ b/src/decoder/plugins/FlacMetadata.cxx @@ -0,0 +1,223 @@ +/* + * Copyright (C) 2003-2014 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" +#include "XiphTags.hxx" +#include "MixRampInfo.hxx" +#include "tag/TagHandler.hxx" +#include "tag/TagTable.hxx" +#include "tag/TagBuilder.hxx" +#include "tag/Tag.hxx" +#include "ReplayGainInfo.hxx" +#include "util/ASCII.hxx" +#include "util/SplitString.hxx" + +#include <string.h> + +static const char * +vorbis_comment_value(const FLAC__StreamMetadata *block, + const char *name) +{ + int offset = + FLAC__metadata_object_vorbiscomment_find_entry_from(block, 0, + name); + if (offset < 0) + return nullptr; + + size_t name_length = strlen(name); + + const FLAC__StreamMetadata_VorbisComment_Entry &vc = + block->data.vorbis_comment.comments[offset]; + const char *comment = (const char *)vc.entry; + + /* 1 is for '=' */ + return comment + name_length + 1; +} + +static bool +flac_find_float_comment(const FLAC__StreamMetadata *block, + const char *cmnt, float *fl) +{ + const char *value = vorbis_comment_value(block, cmnt); + if (value == nullptr) + return false; + + *fl = (float)atof(value); + return true; +} + +bool +flac_parse_replay_gain(ReplayGainInfo &rgi, + const FLAC__StreamMetadata *block) +{ + rgi.Clear(); + + bool found = false; + 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; +} + +gcc_pure +static std::string +flac_find_string_comment(const FLAC__StreamMetadata *block, const char *cmnt) +{ + const char *value = vorbis_comment_value(block, cmnt); + if (value == nullptr) + return std::string(); + + return std::string(value); +} + +MixRampInfo +flac_parse_mixramp(const FLAC__StreamMetadata *block) +{ + MixRampInfo mix_ramp; + mix_ramp.SetStart(flac_find_string_comment(block, "mixramp_start")); + mix_ramp.SetEnd(flac_find_string_comment(block, "mixramp_end")); + return mix_ramp; +} + +/** + * Checks if the specified name matches the entry's name, and if yes, + * returns the comment value; + */ +static const char * +flac_comment_value(const FLAC__StreamMetadata_VorbisComment_Entry *entry, + const char *name) +{ + size_t name_length = strlen(name); + const char *comment = (const char*)entry->entry; + + if (!StringEqualsCaseASCII(comment, name, name_length)) + return nullptr; + + if (comment[name_length] == '=') { + 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, TagType tag_type, + const struct tag_handler *handler, void *handler_ctx) +{ + const char *value = flac_comment_value(entry, name); + if (value != nullptr) { + tag_handler_invoke_tag(handler, handler_ctx, tag_type, value); + 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) { + const char *comment = (const char *)entry->entry; + const SplitString split(comment, '='); + if (split.IsDefined() && !split.IsEmpty()) + tag_handler_invoke_pair(handler, handler_ctx, + split.GetFirst(), + split.GetSecond()); + } + + 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], (TagType)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; + } +} + +Tag +flac_vorbis_comments_to_tag(const FLAC__StreamMetadata_VorbisComment *comment) +{ + TagBuilder tag_builder; + flac_scan_comments(comment, &add_tag_handler, &tag_builder); + return tag_builder.Commit(); +} + +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()); +} |