+static void free_tags(struct taginfo *tags)
+{
+ freep(&tags->artist);
+ freep(&tags->title);
+ freep(&tags->album);
+ freep(&tags->year);
+ freep(&tags->comment);
+}
+
+static bool copy_if_tag_type(const char *tag, int taglen, const char *type,
+ char **p)
+{
+ char *q = key_value_copy(tag, taglen, type);
+ if (!q)
+ return false;
+ free(*p);
+ *p = q;
+ return true;
+}
+
+static void flac_read_vorbis_comments(FLAC__StreamMetadata_VorbisComment *vc,
+ struct taginfo *tags)
+{
+ int i;
+ FLAC__StreamMetadata_VorbisComment_Entry *comment = vc->comments;
+
+ PARA_INFO_LOG("found %u vorbis comments\n", vc->num_comments);
+ for (i = 0; i < vc->num_comments; i++) {
+ char *e = (char *)comment[i].entry;
+ int len = comment[i].length;
+ if (copy_if_tag_type(e, len, "artist", &tags->artist))
+ continue;
+ if (copy_if_tag_type(e, len, "title", &tags->title))
+ continue;
+ if (copy_if_tag_type(e, len, "album", &tags->album))
+ continue;
+ if (copy_if_tag_type(e, len, "year", &tags->year))
+ continue;
+ if (copy_if_tag_type(e, len, "comment", &tags->comment))
+ continue;
+ }
+}
+
+static int flac_read_meta(struct private_flac_afh_data *pfad)
+{
+ int ret;
+ FLAC__IOCallbacks meta_callbacks = {
+ .read = meta_read_cb,
+ .write = NULL,
+ .seek = meta_seek_cb,
+ .tell = meta_tell_cb,
+ .eof = meta_eof_cb,
+ .close = meta_close_cb
+ };
+ FLAC__Metadata_Chain *chain;
+ FLAC__Metadata_Iterator *iter;
+ FLAC__StreamMetadata_StreamInfo *info = NULL;
+ FLAC__bool ok;
+
+ chain = FLAC__metadata_chain_new();
+ if (!chain)
+ return -E_FLAC_CHAIN_ALLOC;
+ ret = -E_FLAC_CHAIN_READ;
+ ok = FLAC__metadata_chain_read_with_callbacks(chain, pfad,
+ meta_callbacks);
+ if (!ok)
+ goto free_chain;
+ ret = -E_FLAC_ITER_ALLOC;
+ iter = FLAC__metadata_iterator_new();
+ if (!iter)
+ goto free_chain;
+ FLAC__metadata_iterator_init(iter, chain);
+ for (;;) {
+ FLAC__StreamMetadata *b;
+ b = FLAC__metadata_iterator_get_block(iter);
+ if (!b)
+ break;
+ if (b->type == FLAC__METADATA_TYPE_STREAMINFO) {
+ info = &b->data.stream_info;
+ ret = -E_FLAC_VARBLOCK;
+ if (info->min_blocksize != info->max_blocksize)
+ goto free_iter;
+ pfad->afhi->frequency = info->sample_rate;
+ pfad->afhi->channels = info->channels;
+ pfad->blocksize = info->min_blocksize;
+ }
+ if (b->type == FLAC__METADATA_TYPE_VORBIS_COMMENT)
+ flac_read_vorbis_comments(&b->data.vorbis_comment,
+ &pfad->afhi->tags);
+ ok = FLAC__metadata_iterator_next(iter);
+ if (!ok)
+ break;
+ }
+ ret = info? 0: -E_FLAC_STREAMINFO;
+free_iter:
+ FLAC__metadata_iterator_delete(iter);
+free_chain:
+ FLAC__metadata_chain_delete(chain);
+ if (ret < 0)
+ free_tags(&pfad->afhi->tags);
+ return ret;
+}
+
+static FLAC__StreamDecoderReadStatus read_cb(
+ __a_unused const FLAC__StreamDecoder *decoder,
+ FLAC__byte buffer[], size_t *bytes, void *client_data)
+{
+ struct private_flac_afh_data *pfad = client_data;
+
+ assert(*bytes > 0);
+ *bytes = copy_data(pfad, buffer, *bytes);
+ if (*bytes == 0)
+ return FLAC__STREAM_DECODER_READ_STATUS_END_OF_STREAM;
+ else
+ return FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
+}
+
+static FLAC__StreamDecoderTellStatus tell_cb(
+ __a_unused const FLAC__StreamDecoder *decoder,
+ FLAC__uint64 *absolute_byte_offset, void *client_data)
+{
+ struct private_flac_afh_data *pfad = client_data;
+
+ *absolute_byte_offset = pfad->fpos;
+ return FLAC__STREAM_DECODER_TELL_STATUS_OK;
+}
+
+/* libflac insits on this callback being present. */
+static FLAC__StreamDecoderWriteStatus write_cb(
+ __a_unused const FLAC__StreamDecoder *decoder,
+ __a_unused const FLAC__Frame *frame,
+ __a_unused const FLAC__int32 *const buffer[],
+ __a_unused void *client_data)
+{
+ return FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
+}
+
+static void error_cb(
+ __a_unused const FLAC__StreamDecoder *decoder,
+ FLAC__StreamDecoderErrorStatus status,
+ __a_unused void *client_data)
+{
+ PARA_ERROR_LOG("%s\n", FLAC__StreamDecoderErrorStatusString[status]);
+}
+
+static int flac_afh_read_chunks(struct private_flac_afh_data *pfad)
+{
+ FLAC__StreamDecoder *decoder;
+ FLAC__StreamDecoderInitStatus init_status;
+ FLAC__bool ok;
+ FLAC__uint64 c;
+ unsigned chunk_table_size = 0;
+ int ret;
+ struct afh_info *afhi = pfad->afhi;
+
+ PARA_INFO_LOG("reading chunk table\n");
+ afhi->chunk_table = NULL;
+ decoder = FLAC__stream_decoder_new();
+ if (!decoder)
+ return -E_FLAC_AFH_DECODER_ALLOC;
+ ret = -E_FLAC_AFH_DECODER_INIT;
+ init_status = FLAC__stream_decoder_init_stream(
+ decoder,
+ read_cb,
+ NULL, /* seek */
+ tell_cb,
+ NULL, /* length */
+ NULL, /* eof */
+ write_cb,
+ NULL,
+ error_cb,
+ pfad
+ );
+ if (init_status != FLAC__STREAM_DECODER_INIT_STATUS_OK)
+ goto free_decoder;
+ ret = -E_FLAC_SKIP_META;
+ ok = FLAC__stream_decoder_process_until_end_of_metadata(decoder);
+ if (!ok)
+ goto free_decoder;
+ for (c = 0;; c++) {
+ FLAC__uint64 pos;
+ FLAC__StreamDecoderState state;
+
+ ret = -E_FLAC_DECODE_POS;
+ ok = FLAC__stream_decoder_get_decode_position(decoder, &pos);
+ if (!ok)
+ goto free_decoder;
+ if (c >= chunk_table_size) {
+ chunk_table_size = 2 * chunk_table_size + 100;
+ afhi->chunk_table = para_realloc(afhi->chunk_table,
+ chunk_table_size * sizeof(uint32_t));
+ }
+ afhi->chunk_table[c] = pos;
+
+ ok = FLAC__stream_decoder_skip_single_frame(decoder);
+ if (!ok)
+ break;
+ state = FLAC__stream_decoder_get_state(decoder);
+ if (state == FLAC__STREAM_DECODER_END_OF_STREAM)
+ break;
+ }
+ afhi->chunks_total = c;
+ ret = 1;
+free_decoder:
+ FLAC__stream_decoder_finish(decoder);
+ FLAC__stream_decoder_delete(decoder);
+ if (ret < 0)
+ freep(&afhi->chunk_table);
+ return ret;
+}
+
+static int flac_get_file_info(char *map, size_t map_bytes, __a_unused int fd,
+ struct afh_info *afhi)
+{
+ struct private_flac_afh_data pfad_struct = {
+ .map = map,
+ .map_bytes = map_bytes,
+ .afhi = afhi
+ }, *pfad = &pfad_struct;
+ int ret;
+ double chunk_time;
+
+ afhi->header_len = 0;
+ ret = flac_read_meta(pfad);
+ if (ret < 0)
+ return ret;
+ pfad->fpos = 0;
+ ret = flac_afh_read_chunks(pfad);
+ if (ret < 0) {
+ free_tags(&afhi->tags);
+ return ret;
+ }
+ afhi->techinfo = make_message("blocksize: %u", pfad->blocksize);
+ afhi->seconds_total = DIV_ROUND_UP(afhi->chunks_total * pfad->blocksize,
+ afhi->frequency);
+ afhi->bitrate = pfad->map_bytes * 8 / afhi->seconds_total / 1024;
+ chunk_time = (double)pfad->blocksize / afhi->frequency;
+ afhi->chunk_tv.tv_sec = chunk_time;
+ chunk_time *= 1000 * 1000;
+ chunk_time -= afhi->chunk_tv.tv_sec * 1000 * 1000;
+ afhi->chunk_tv.tv_usec = chunk_time;
+ return 1;
+}
+