static int mov_read_mfra(MOVContext *c, AVIOContext *f) { int64_t stream_size = avio_size(f); int64_t original_pos = avio_tell(f); int64_t seek_ret; int32_t mfra_size; int ret = -1; if ((seek_ret = avio_seek(f, stream_size - 4, SEEK_SET)) < 0) { ret = seek_ret; goto fail; } mfra_size = avio_rb32(f); if (mfra_size < 0 || mfra_size > stream_size) { av_log(c->fc, AV_LOG_DEBUG, "doesn't look like mfra (unreasonable size)\n"); goto fail; } if ((seek_ret = avio_seek(f, -mfra_size, SEEK_CUR)) < 0) { ret = seek_ret; goto fail; } if (avio_rb32(f) != mfra_size) { av_log(c->fc, AV_LOG_DEBUG, "doesn't look like mfra (size mismatch)\n"); goto fail; } if (avio_rb32(f) != MKBETAG('m', 'f', 'r', 'a')) { av_log(c->fc, AV_LOG_DEBUG, "doesn't look like mfra (tag mismatch)\n"); goto fail; } ret = 0; av_log(c->fc, AV_LOG_VERBOSE, "stream has mfra\n"); while (!read_tfra(c, f)) { /* Empty */ } fail: seek_ret = avio_seek(f, original_pos, SEEK_SET); if (seek_ret < 0) { av_log(c->fc, AV_LOG_ERROR, "failed to seek back after looking for mfra\n"); ret = seek_ret; } return ret; }