/**
* Determine the size of an inline header.
* @param buf input buffer, starting with the "fLaC" marker
* @param buf_size buffer size
* @return number of bytes in the header, or 0 if more data is needed
*/
static int get_metadata_size(const uint8_t *buf, int buf_size)
{
int metadata_last, metadata_size;
const uint8_t *buf_end = buf + buf_size;
buf += 4;
do {
if (buf_end - buf < 4)
return 0;
flac_parse_block_header(buf, &metadata_last, NULL, &metadata_size);
buf += 4;
if (buf_end - buf < metadata_size) {
/* need more data in order to read the complete header */
return 0;
}
buf += metadata_size;
} while (!metadata_last);
return buf_size - (buf_end - buf);
}
/**
* Parse the STREAMINFO from an inline header.
* @param s the flac decoding context
* @param buf input buffer, starting with the "fLaC" marker
* @param buf_size buffer size
* @return non-zero if metadata is invalid
*/
static int parse_streaminfo(FLACContext *s, const uint8_t *buf, int buf_size)
{
int metadata_type, metadata_size, ret;
if (buf_size < FLAC_STREAMINFO_SIZE+8) {
/* need more data */
return 0;
}
flac_parse_block_header(&buf[4], NULL, &metadata_type, &metadata_size);
if (metadata_type != FLAC_METADATA_TYPE_STREAMINFO ||
metadata_size != FLAC_STREAMINFO_SIZE) {
return AVERROR_INVALIDDATA;
}
ff_flac_parse_streaminfo(s->avctx, (FLACStreaminfo *)s, &buf[8]);
ret = allocate_buffers(s);
if (ret < 0)
return ret;
flac_set_bps(s);
ff_flacdsp_init(&s->dsp, s->avctx->sample_fmt, s->bps);
s->got_streaminfo = 1;
return 0;
}
static int flac_read_header(AVFormatContext *s)
{
int ret, metadata_last=0, metadata_type, metadata_size, found_streaminfo=0;
uint8_t header[4];
uint8_t *buffer=NULL;
AVStream *st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
st->codec->codec_id = AV_CODEC_ID_FLAC;
st->need_parsing = AVSTREAM_PARSE_FULL_RAW;
/* the parameters will be extracted from the compressed bitstream */
/* if fLaC marker is not found, assume there is no header */
if (avio_rl32(s->pb) != MKTAG('f','L','a','C')) {
avio_seek(s->pb, -4, SEEK_CUR);
return 0;
}
/* process metadata blocks */
while (!avio_feof(s->pb) && !metadata_last) {
avio_read(s->pb, header, 4);
flac_parse_block_header(header, &metadata_last, &metadata_type,
&metadata_size);
switch (metadata_type) {
/* allocate and read metadata block for supported types */
case FLAC_METADATA_TYPE_STREAMINFO:
case FLAC_METADATA_TYPE_CUESHEET:
case FLAC_METADATA_TYPE_PICTURE:
case FLAC_METADATA_TYPE_VORBIS_COMMENT:
buffer = av_mallocz(metadata_size + FF_INPUT_BUFFER_PADDING_SIZE);
if (!buffer) {
return AVERROR(ENOMEM);
}
if (avio_read(s->pb, buffer, metadata_size) != metadata_size) {
RETURN_ERROR(AVERROR(EIO));
}
break;
/* skip metadata block for unsupported types */
default:
ret = avio_skip(s->pb, metadata_size);
if (ret < 0)
return ret;
}
if (metadata_type == FLAC_METADATA_TYPE_STREAMINFO) {
FLACStreaminfo si;
/* STREAMINFO can only occur once */
if (found_streaminfo) {
RETURN_ERROR(AVERROR_INVALIDDATA);
}
if (metadata_size != FLAC_STREAMINFO_SIZE) {
RETURN_ERROR(AVERROR_INVALIDDATA);
}
found_streaminfo = 1;
st->codec->extradata = buffer;
st->codec->extradata_size = metadata_size;
buffer = NULL;
/* get codec params from STREAMINFO header */
avpriv_flac_parse_streaminfo(st->codec, &si, st->codec->extradata);
/* set time base and duration */
if (si.samplerate > 0) {
avpriv_set_pts_info(st, 64, 1, si.samplerate);
if (si.samples > 0)
st->duration = si.samples;
}
} else if (metadata_type == FLAC_METADATA_TYPE_CUESHEET) {
uint8_t isrc[13];
uint64_t start;
const uint8_t *offset;
int i, chapters, track, ti;
if (metadata_size < 431)
RETURN_ERROR(AVERROR_INVALIDDATA);
offset = buffer + 395;
chapters = bytestream_get_byte(&offset) - 1;
if (chapters <= 0)
RETURN_ERROR(AVERROR_INVALIDDATA);
for (i = 0; i < chapters; i++) {
if (offset + 36 - buffer > metadata_size)
RETURN_ERROR(AVERROR_INVALIDDATA);
start = bytestream_get_be64(&offset);
track = bytestream_get_byte(&offset);
bytestream_get_buffer(&offset, isrc, 12);
isrc[12] = 0;
offset += 14;
ti = bytestream_get_byte(&offset);
if (ti <= 0) RETURN_ERROR(AVERROR_INVALIDDATA);
offset += ti * 12;
avpriv_new_chapter(s, track, st->time_base, start, AV_NOPTS_VALUE, isrc);
}
av_freep(&buffer);
} else if (metadata_type == FLAC_METADATA_TYPE_PICTURE) {
ret = ff_flac_parse_picture(s, buffer, metadata_size);
av_freep(&buffer);
if (ret < 0) {
av_log(s, AV_LOG_ERROR, "Error parsing attached picture.\n");
return ret;
}
} else {
/* STREAMINFO must be the first block */
if (!found_streaminfo) {
RETURN_ERROR(AVERROR_INVALIDDATA);
}
/* process supported blocks other than STREAMINFO */
if (metadata_type == FLAC_METADATA_TYPE_VORBIS_COMMENT) {
AVDictionaryEntry *chmask;
ret = ff_vorbis_comment(s, &s->metadata, buffer, metadata_size, 1);
if (ret < 0) {
av_log(s, AV_LOG_WARNING, "error parsing VorbisComment metadata\n");
} else if (ret > 0) {
s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED;
}
/* parse the channels mask if present */
chmask = av_dict_get(s->metadata, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0);
if (chmask) {
uint64_t mask = strtol(chmask->value, NULL, 0);
if (!mask || mask & ULLN(~0x3ffff)) {
av_log(s, AV_LOG_WARNING,
"Invalid value of WAVEFORMATEXTENSIBLE_CHANNEL_MASK\n");
} else {
st->codec->channel_layout = mask;
av_dict_set(&s->metadata, "WAVEFORMATEXTENSIBLE_CHANNEL_MASK", NULL, 0);
}
}
}
av_freep(&buffer);
}
}
ret = ff_replaygain_export(st, s->metadata);
if (ret < 0)
return ret;
return 0;
fail:
av_free(buffer);
return ret;
}
