static int asfrtp_parse_packet(AVFormatContext *s, PayloadContext *asf, AVStream *st, AVPacket *pkt, uint32_t *timestamp, const uint8_t *buf, int len, int flags) { AVIOContext *pb = &asf->pb; int res, mflags, len_off; RTSPState *rt = s->priv_data; if (!rt->asf_ctx) if (len > 0) { int off, out_len = 0; if (len < 4) av_freep(&asf->buf); ffio_init_context(pb, buf, len, 0, NULL, NULL, NULL, NULL); while (avio_tell(pb) + 4 < len) { int start_off = avio_tell(pb); mflags = avio_r8(pb); if (mflags & 0x80) flags |= RTP_FLAG_KEY; len_off = avio_rb24(pb); if (mflags & 0x20) /**< relative timestamp */ avio_skip(pb, 4); if (mflags & 0x10) /**< has duration */ avio_skip(pb, 4); if (mflags & 0x8) /**< has location ID */ avio_skip(pb, 4); off = avio_tell(pb); if (!(mflags & 0x40)) { /** * If 0x40 is not set, the len_off field specifies an offset * of this packet's payload data in the complete (reassembled) * ASF packet. This is used to spread one ASF packet over * multiple RTP packets. */ if (asf->pktbuf && len_off != avio_tell(asf->pktbuf)) { uint8_t *p; avio_close_dyn_buf(asf->pktbuf, &p); asf->pktbuf = NULL; av_free(p); } if (!len_off && !asf->pktbuf && (res = avio_open_dyn_buf(&asf->pktbuf)) < 0) return res; if (!asf->pktbuf) return AVERROR(EIO); avio_write(asf->pktbuf, buf + off, len - off); avio_skip(pb, len - off); if (!(flags & RTP_FLAG_MARKER)) out_len = avio_close_dyn_buf(asf->pktbuf, &asf->buf); asf->pktbuf = NULL; } else { /** * If 0x40 is set, the len_off field specifies the length of * the next ASF packet that can be read from this payload * data alone. This is commonly the same as the payload size, * but could be less in case of packet splitting (i.e. * multiple ASF packets in one RTP packet). */ int cur_len = start_off + len_off - off; int prev_len = out_len; out_len += cur_len; asf->buf = av_realloc(asf->buf, out_len); memcpy(asf->buf + prev_len, buf + off, FFMIN(cur_len, len - off)); avio_skip(pb, cur_len); } } init_packetizer(pb, asf->buf, out_len); pb->pos += rt->asf_pb_pos; pb->eof_reached = 0; rt->asf_ctx->pb = pb; } for (;;) { int i; res = av_read_packet(rt->asf_ctx, pkt); rt->asf_pb_pos = avio_tell(pb); if (res != 0) break; for (i = 0; i < s->nb_streams; i++) { if (s->streams[i]->id == rt->asf_ctx->streams[pkt->stream_index]->id) { pkt->stream_index = i; return 1; // FIXME: return 0 if last packet } } av_free_packet(pkt); } return res == 1 ? -1 : res; }