MT#63317 add rtpext printing abstraction

Change-Id: I50b4bc3feef4445ccd87f4296504ec196bb8083a

daemon/codec.c

@@ -2460,17 +2460,13 @@ void codec_output_rtp(struct media_packet *mp, struct codec_scheduler *csch,
 	rh->timestamp = htonl(ts);
 	rh->ssrc = htonl(ssrc_out->h.ssrc);
 
-	if (mp->extensions.len) {
-		rh->v_p_x_cc |= 0x10;
-		char *exts = buf + sizeof(*rh);
-		memcpy(exts, mp->extensions.s, mp->extensions.len);
-	}
+	size_t ext_len = mp->sink.rtpext->print(rh, buf + sizeof(*rh), mp);
 
 	// add to output queue
 	struct codec_packet *p = g_new0(__typeof(*p), 1);
 	p->link.data = p;
 	p->s.s = buf;
-	p->s.len = payload_len + sizeof(struct rtp_header) + mp->extensions.len;
+	p->s.len = payload_len + sizeof(struct rtp_header) + ext_len;
 	payload_tracker_add(&ssrc_out->tracker, handler->dest_pt.payload_type);
 	p->free_func = bufferpool_unref;
 	p->ttq_entry.source = handler;
@@ -4541,11 +4537,12 @@ void packet_encoded_packetize(AVPacket *pkt, struct codec_ssrc_handler *ch, stru
 		// figure out how big of a buffer we need
 		size_t payload_len = MAX(MAX(pkt->size, ch->bytes_per_packet),
 				sizeof(struct telephone_event_payload));
-		size_t payload_ext_len = payload_len + mp->extensions.len;
+		size_t ext_len = mp->sink.rtpext->length(mp);
+		size_t payload_ext_len = payload_len + ext_len;
 		size_t pkt_len = sizeof(struct rtp_header) + payload_ext_len + RTP_BUFFER_TAIL_ROOM;
 		// prepare our buffers
 		char *buf = bufferpool_alloc(media_bufferpool, pkt_len);
-		char *payload = buf + sizeof(struct rtp_header) + mp->extensions.len;
+		char *payload = buf + sizeof(struct rtp_header) + ext_len;
 		// tell our packetizer how much we want
 		str inout = STR_LEN(payload, payload_len);
 		// and request a packet

daemon/media_player.c

@@ -789,6 +789,7 @@ static void media_player_cache_packet(struct media_player_cache_entry *entry, ch
 	struct media_packet packet = {
 		.rtp = &rtp,
 		.cache_entry = entry,
+		.sink = { .rtpext = &rtpext_printer_copy },
 	};
 	packet.raw = STR_LEN(buf, len);
 	packet.payload = packet.raw;

daemon/media_socket.c

@@ -2053,6 +2053,31 @@ void unkernelize(struct packet_stream *ps, const char *reason) {
 }
 
 
+
+static size_t rtpext_printer_copy_length(const struct media_packet *mp) {
+	if (mp->rtcp)
+		return 0;
+	return mp->extensions.len;
+}
+static size_t rtpext_printer_copy_print(struct rtp_header *rh, void *dst, const struct media_packet *mp) {
+	if (!mp->extensions.len)
+		return 0;
+	if (mp->rtcp)
+		return 0;
+
+	rh->v_p_x_cc |= 0x10;
+	memcpy(dst, mp->extensions.s, mp->extensions.len);
+
+	return mp->extensions.len;
+}
+
+const struct rtpext_printer rtpext_printer_copy = {
+	.length = rtpext_printer_copy_length,
+	.print = rtpext_printer_copy_print,
+};
+
+
+
 // `out_media` can be NULL XXX streamline this to remove this exception
 const struct streamhandler *determine_handler(const struct transport_protocol *in_proto,
 		struct call_media *out_media, bool must_recrypt)
@@ -2087,8 +2112,18 @@ err:
 }
 
 
+__attribute__((nonnull(1)))
+static void __determine_rtpext_handler(struct call_media *in, struct call_media *out, struct sink_handler *sh) {
+	if (!sh || !out)
+		return;
+
+	sh->rtpext = &rtpext_printer_copy;
+}
+
+
 // sh->sink must be set
 void sink_handler_set_generic(struct sink_handler *sh) {
+	sh->rtpext = &rtpext_printer_copy;
 	sh->handler = determine_handler(&transport_protocols[PROTO_RTP_AVP], sh->sink->media, true);
 }
 
@@ -2106,8 +2141,11 @@ const struct streamhandler *determine_sink_handler(struct packet_stream *in, str
 	if (MEDIA_ISSET(in->media, PASSTHRU))
 		goto noop;
 
-	in_proto = in->media->protocol;
-	out_proto = out ? out->media->protocol : NULL;
+	__auto_type media_in = in->media;
+	__auto_type media_out = out ? out->media : NULL;
+
+	in_proto = media_in->protocol;
+	out_proto = media_out ? media_out->protocol : NULL;
 
 	if (!in_proto)
 		goto err;
@@ -2135,14 +2173,20 @@ const struct streamhandler *determine_sink_handler(struct packet_stream *in, str
 	ret = determine_handler(in_proto, out ? out->media : NULL, must_recrypt);
 	if (sh)
 		sh->handler = ret;
+
+	__determine_rtpext_handler(media_in, media_out, sh);
+
 	return ret;
 
 err:
 	ilog(LOG_WARNING, "Unknown transport protocol encountered");
 noop:
 	ret = &__sh_noop;
-	if (sh)
+	if (sh) {
 		sh->handler = ret;
+		sh->rtpext = &rtpext_printer_copy;
+	}
+
 	return ret;
 }
 

include/media_socket.h

@@ -254,6 +254,11 @@ struct sink_attrs {
 	bool egress:1;
 };
 
+struct rtpext_printer {
+	size_t (*length)(const struct media_packet *);
+	size_t (*print)(struct rtp_header *, void *dst, const struct media_packet *);
+};
+
 /**
  * During actual packet handling and forwarding,
  * only the sink_handler objects (and the packet_stream objects they are related to) are used.
@@ -263,8 +268,13 @@ struct sink_handler {
 	const struct streamhandler *handler;
 	int kernel_output_idx;
 	struct sink_attrs attrs;
+	const struct rtpext_printer *rtpext;
 };
 
+
+extern const struct rtpext_printer rtpext_printer_copy; // also acts as a dummy printer
+
+
 TYPED_GQUEUE(extmap_data, struct rtp_extension_data);
 
 struct media_packet {