TT#86850 support DNS lookup for advertised address

closes #969

Change-Id: I3712a0977700719765bbd45985306e598067c0af

daemon/main.c

@@ -276,8 +276,13 @@ static int if_addr_parse(GQueue *q, char *s, struct ifaddrs *ifas) {
 
 	ZERO(adv);
 	if (c) {
-		if (sockaddr_parse_any(&adv, c))
+		if (sockaddr_parse_any(&adv, c)) {
+			ilog(LOG_DEBUG, "Could not parse '%s' as an address, attempting DNS lookup", c);
+			if (sockaddr_getaddrinfo(&adv, c)) {
+				ilog(LOG_WARN, "DNS lookup for '%s' failed", c);
 				return -1;
+			}
+		}
 		if (is_addr_unspecified(&adv))
 			return -1;
 	}

daemon/rtpengine.pod

@@ -702,8 +702,8 @@ The command-line options B<-i> or B<--interface>, or equivalently the
 B<interface> config file option, specify local network interfaces for RTP.
 At least one must be given, but multiple can be specified.
 The format of the value is [I<NAME>B</>]I<IP>[!I<IP>] with I<IP> being
-either an IPv4 address, an IPv6 address, or the name of a system network
-interface (such as I<eth0>).
+either an IPv4 address, an IPv6 address, the name of a system network interface
+(such as I<eth0>), or a DNS host name (such as I<test.example.com>).
 
 The possibility of configuring a network interface by name rather than
 by address should not be confused with the logical interface name used
@@ -717,6 +717,9 @@ I<eth0>, you would use the syntax I<int/eth0>.
 (Unless omitted, the second I<IP> token used for the advertised address
 must be an actual network address and cannot be an interface name.)
 
+If DNS host names are used instead of addresses or interface names, the lookup
+will be done only once during daemon start-up.
+
 To configure multiple interfaces using the command-line options,
 simply present multiple B<-i> or B<--interface> options.
 When using the config file, only use a single B<interface> line,