- if (buf[6] == 1) {
- /* the chunk contains audio */
- *data_size = vmdaudio_loadsound(s, output_samples, p, 0, buf_size - 16);
- } else if (buf[6] == 2) {
- /* initial chunk, may contain audio and silence */
- uint32_t flags = AV_RB32(p);
- int raw_block_size = s->block_align * s->bits / 8;
- int silent_chunks;
- if(flags == 0xFFFFFFFF)
- silent_chunks = 32;
- else
- silent_chunks = av_log2(flags + 1);
- if(*data_size < (s->block_align*silent_chunks + buf_size - 20) * 2)
- return -1;
- *data_size = 0;
- memset(output_samples, 0, raw_block_size * silent_chunks);
- output_samples += raw_block_size * silent_chunks;
- *data_size = raw_block_size * silent_chunks;
- *data_size += vmdaudio_loadsound(s, output_samples, p + 4, 0, buf_size - 20);
- } else if (buf[6] == 3) {
- /* silent chunk */
- *data_size = vmdaudio_loadsound(s, output_samples, p, 1, 0);
+ block_type = buf[6];
+ if (block_type < BLOCK_TYPE_AUDIO || block_type > BLOCK_TYPE_SILENCE) {
+ av_log(avctx, AV_LOG_ERROR, "unknown block type: %d\n", block_type);
+ return AVERROR(EINVAL);
+ }
+ buf += 16;
+ buf_size -= 16;
+
+ silent_chunks = 0;
+ if (block_type == BLOCK_TYPE_INITIAL) {
+ uint32_t flags = AV_RB32(buf);
+ silent_chunks = av_popcount(flags);
+ buf += 4;
+ buf_size -= 4;
+ } else if (block_type == BLOCK_TYPE_SILENCE) {
+ silent_chunks = 1;
+ buf_size = 0; // should already be zero but set it just to be sure