rtp: send all RTCP packets as compound packets (baresip#1222)

According to RFC 3550 section 6.1 this is a MUST.

src/rtp/rtcp.c

@@ -27,6 +27,11 @@ static int rtcp_quick_send(struct rtp_sock *rs, enum rtcp_type type,
 
 	mb->pos = RTCP_HEADROOM;
 
+	err  = rtcp_make_sr(rs, mb);
+	err |= rtcp_make_sdes_cname(rs, mb);
+	if (err)
+		goto out;
+
 	va_start(ap, count);
 	err = rtcp_vencode(mb, type, count, ap);
 	va_end(ap);
@@ -36,6 +41,10 @@ static int rtcp_quick_send(struct rtp_sock *rs, enum rtcp_type type,
 	if (!err)
 		err = rtcp_send(rs, mb);
 
+	if (!err)
+		rtcp_schedule_report(rs);
+
+out:
 	mem_deref(mb);
 
 	return err;

src/rtp/rtcp.h

@@ -44,8 +44,12 @@ int rtcp_rr_alloc(struct rtcp_rr **rrp, size_t count);
 int rtcp_rr_encode(struct mbuf *mb, const struct rtcp_rr *rr);
 int rtcp_rr_decode(struct mbuf *mb, struct rtcp_rr *rr);
 
+/* SR (Sender report) */
+int rtcp_make_sr(const struct rtp_sock *rs, struct mbuf *mb);
+
 /* SDES (Source Description) */
 int rtcp_sdes_decode(struct mbuf *mb, struct rtcp_sdes *sdes);
+int rtcp_make_sdes_cname(const struct rtp_sock *rs, struct mbuf *mb);
 
 /* RTCP Feedback */
 int rtcp_rtpfb_gnack_encode(struct mbuf *mb, uint16_t pid, uint16_t blp);
@@ -86,3 +90,4 @@ void rtcp_sess_tx_rtp(struct rtcp_sess *sess, uint32_t ts, uint64_t jfs_rt,
 		      size_t payload_size);
 void rtcp_sess_rx_rtp(struct rtcp_sess *sess, struct rtp_header *hdr,
 		      size_t payload_size, const struct sa *peer);
+void rtcp_schedule_report(const struct rtp_sock *rs);

src/rtp/sess.c

@@ -459,6 +459,16 @@ static int mk_sr(struct rtcp_sess *sess, struct mbuf *mb)
 }
 
 
+int rtcp_make_sr(const struct rtp_sock *rs, struct mbuf *mb)
+{
+	struct rtcp_sess *sess = rtp_rtcp_sess(rs);
+	if (!sess)
+		return EINVAL;
+
+	return mk_sr(sess, mb);
+}
+
+
 static int sdes_encode_handler(struct mbuf *mb, void *arg)
 {
 	struct rtcp_sess *sess = arg;
@@ -479,6 +489,16 @@ static int mk_sdes(struct rtcp_sess *sess, struct mbuf *mb)
 }
 
 
+int rtcp_make_sdes_cname(const struct rtp_sock *rs, struct mbuf *mb)
+{
+	struct rtcp_sess *sess = rtp_rtcp_sess(rs);
+	if (!sess)
+		return EINVAL;
+
+	return mk_sdes(sess, mb);
+}
+
+
 static int send_rtcp_report(struct rtcp_sess *sess)
 {
 	struct mbuf *mb;
@@ -556,6 +576,16 @@ static void schedule(struct rtcp_sess *sess)
 }
 
 
+void rtcp_schedule_report(const struct rtp_sock *rs)
+{
+	struct rtcp_sess *sess = rtp_rtcp_sess(rs);
+	if (!sess)
+		return;
+
+	tmr_start(&sess->tmr, sess->interval, timeout, sess);
+}
+
+
 void rtcp_sess_tx_rtp(struct rtcp_sess *sess, uint32_t ts, uint64_t jfs_rt,
 			   size_t payload_size)
 {