transp.c: add sip_transp_add_sock

to add SIP transport protocol without opening a listening socket and
adapt sip_transp_send accordingly to make UDP work.

include/re_sip.h

@@ -311,6 +311,8 @@ void sip_set_trace_handler(struct sip *sip, sip_trace_h *traceh);
 /* transport */
 int  sip_transp_add(struct sip *sip, enum sip_transp tp,
 		    const struct sa *laddr, ...);
+int sip_transp_add_sock(struct sip *sip, enum sip_transp tp,
+			bool listen, const struct sa *laddr, ...);
 int  sip_transp_add_websock(struct sip *sip, enum sip_transp tp,
 			    const struct sa *laddr,
 			    bool server, const char *cert, struct tls *tls);

src/sip/transp.c

@@ -1195,17 +1195,17 @@ static void http_req_handler(struct http_conn *hc, const struct http_msg *msg,
  *
  * @param sip   SIP stack instance
  * @param tp    SIP Transport
+ * @param listen True to open listening socket
  * @param laddr Local network address
- * @param ...   Optional transport parameters such as TLS context
+ * @param ap    Optional transport parameters such as TLS context
  *
  * @return 0 if success, otherwise errorcode
  */
-int sip_transp_add(struct sip *sip, enum sip_transp tp,
-		   const struct sa *laddr, ...)
+static int add_transp(struct sip *sip, enum sip_transp tp,
+		      bool listen, const struct sa *laddr, va_list ap)
 {
 	struct sip_transport *transp;
 	struct tls *tls;
-	va_list ap;
 	int err = 0;
 
 	if (!sip || !laddr || !sa_isset(laddr, SA_ADDR))
@@ -1221,13 +1221,25 @@ int sip_transp_add(struct sip *sip, enum sip_transp tp,
 			mem_deref(transp);
 			return err;
 		}
+
+		tls = va_arg(ap, struct tls *);
+		if (!tls) {
+			err = EINVAL;
+			goto out;
+		}
+
+		transp->tls = mem_ref(tls);
 	}
 
 	list_append(&sip->transpl, &transp->le, transp);
 	transp->sip = sip;
 	transp->tp  = tp;
 
-	va_start(ap, laddr);
+	if (!listen) {
+		transp->laddr = *laddr;
+		sa_set_port(&transp->laddr, 0);
+		return err;
+	}
 
 	switch (tp) {
 
@@ -1241,16 +1253,6 @@ int sip_transp_add(struct sip *sip, enum sip_transp tp,
 		break;
 
 	case SIP_TRANSP_TLS:
-		tls = va_arg(ap, struct tls *);
-		if (!tls) {
-			err = EINVAL;
-			break;
-		}
-
-		transp->tls = mem_ref(tls);
-
-		/*@fallthrough@*/
-
 	case SIP_TRANSP_TCP:
 		err = tcp_listen((struct tcp_sock **)&transp->sock, laddr,
 				 tcp_connect_handler, transp);
@@ -1265,15 +1267,63 @@ int sip_transp_add(struct sip *sip, enum sip_transp tp,
 		break;
 	}
 
-	va_end(ap);
-
+out:
 	if (err)
 		mem_deref(transp);
 
 	return err;
 }
 
 
+/**
+ * Add a SIP transport
+ *
+ * @param sip   SIP stack instance
+ * @param tp    SIP Transport
+ * @param laddr Local network address
+ * @param ...   Optional transport parameters such as TLS context
+ *
+ * @return 0 if success, otherwise errorcode
+ */
+int sip_transp_add(struct sip *sip, enum sip_transp tp,
+		   const struct sa *laddr, ...)
+{
+	int err;
+	va_list ap;
+
+	va_start(ap, laddr);
+	err = add_transp(sip, tp, true, laddr, ap);
+	va_end(ap);
+
+	return err;
+}
+
+
+/**
+ * Add a SIP transport and open listening socket if requested
+ *
+ * @param sip    SIP stack instance
+ * @param tp     SIP Transport
+ * @param listen True to open listening socket
+ * @param laddr  Local network address
+ * @param ...	 Optional transport parameters such as TLS context
+ *
+ * @return 0 if success, otherwise errorcode
+ */
+int sip_transp_add_sock(struct sip *sip, enum sip_transp tp,
+			bool listen, const struct sa *laddr, ...)
+{
+	int err;
+	va_list ap;
+
+	va_start(ap, laddr);
+	err = add_transp(sip, tp, listen, laddr, ap);
+	va_end(ap);
+
+	return err;
+}
+
+
 /**
  * Add a SIP websocket transport
  *
@@ -1435,7 +1485,7 @@ int sip_transp_send(struct sip_connqent **qentp, struct sip *sip, void *sock,
 		    struct mbuf *mb, sip_conn_h *connh, sip_transp_h *transph,
 		    void *arg)
 {
-	const struct sip_transport *transp;
+	struct sip_transport *transp;
 	struct sip_conn *conn;
 	bool secure = false;
 	struct sa dsttmp;
@@ -1459,17 +1509,35 @@ int sip_transp_send(struct sip_connqent **qentp, struct sip *sip, void *sock,
 		if (err)
 			return err;
 
-		if (connh)
-			connh(&laddr, dst, mb, arg);
-
 		if (!sock) {
-			transp = transp_find(sip, tp, sa_af(&dsttmp), &dsttmp);
+			transp = (struct sip_transport	*)
+				transp_find(sip, tp, sa_af(&dsttmp), &dsttmp);
 			if (!transp)
 				return EPROTONOSUPPORT;
 
+			if (!transp->sock) {
+				err = udp_listen((struct udp_sock **)
+						 &transp->sock, &transp->laddr,
+				 	 	 udp_recv_handler, transp);
+				if (err)
+					break;
+
+				err = udp_local_get(transp->sock,
+						    &transp->laddr);
+				if (err) {
+					transp->sock = mem_deref(transp->sock);
+					break;
+				}
+
+				laddr = transp->laddr;
+			}
+
 			sock = transp->sock;
 		}
 
+		if (connh)
+			connh(&laddr, dst, mb, arg);
+
 		trace_send(sip, tp, sock, &dsttmp, mb);
 
 		err = udp_send(sock, &dsttmp, mb);
@@ -1773,9 +1841,10 @@ static bool debug_handler(struct le *le, void *arg)
 	const struct sip_transport *transp = le->data;
 	struct re_printf *pf = arg;
 
-	(void)re_hprintf(pf, "  %J (%s)\n",
+	(void)re_hprintf(pf, "  %J (%s) (%slistening)\n",
 			 &transp->laddr,
-			 sip_transp_name(transp->tp));
+			 sip_transp_name(transp->tp),
+			 sa_port(&transp->laddr) ? "" : "not ");
 
 	return false;
 }