MT#55283 support interface aliases

Change-Id: Ifd85bc49201bab1ab89a8d240ee682a6d1655868

daemon/main.c

@@ -276,11 +276,20 @@ static int if_addr_parse(intf_config_q *q, char *s, struct ifaddrs *ifas) {
 	struct intf_config *ifa;
 
 	/* name */
-	c = strchr(s, '/');
+	c = strpbrk(s, "/=");
 	if (c) {
+		char cc = *c;
 		*c++ = 0;
 		str_init(&name, s);
 		s = c;
+		if (cc == '=') {
+			// foo=bar
+			ifa = g_slice_alloc0(sizeof(*ifa));
+			str_init_dup_str(&ifa->name, &name);
+			str_init_dup(&ifa->alias, s);
+			t_queue_push_tail(q, ifa);
+			return 0;
+		}
 	}
 	else
 		str_init(&name, "default");
@@ -1073,6 +1082,7 @@ static void fill_initial_rtpe_cfg(struct rtpengine_config* ini_rtpe_cfg) {
 		gptr_data = g_slice_alloc0(sizeof(*gptr_data));
 		memcpy(gptr_data, l->data, sizeof(*gptr_data));
 		str_init_dup_str(&gptr_data->name, &l->data->name);
+		str_init_dup_str(&gptr_data->alias, &l->data->alias);
 
 		t_queue_push_tail(&ini_rtpe_cfg->interfaces, gptr_data);
 	}
@@ -1148,6 +1158,7 @@ static void fill_initial_rtpe_cfg(struct rtpengine_config* ini_rtpe_cfg) {
 
 static void free_config_interfaces(struct intf_config *i) {
 	str_free_dup(&i->name);
+	str_free_dup(&i->alias);
 	g_slice_free1(sizeof(*i), i);
 }
 

daemon/media_socket.c

@@ -779,7 +779,25 @@ static void __interface_append(struct intf_config *ifa, sockfamily_t *fam, bool
 	lif = __get_logical_interface(&ifa->name, fam);
 
 	if (!lif) {
-		if (!create)
+		if (!create) {
+			// alias?
+			if (!ifa->alias.len)
+				return;
+
+			struct logical_intf *alias = __get_logical_interface(&ifa->alias, fam);
+			if (!alias)
+				return;
+
+			struct intf_key *key = g_new0(__typeof(*key), 1);
+			key->name = ifa->name;
+			key->preferred_family = fam;
+
+			t_hash_table_insert(__logical_intf_name_family_hash, key, alias);
+
+			return;
+		}
+
+		if (ifa->alias.len) // handled in second run
 			return;
 
 		lif = g_slice_alloc0(sizeof(*lif));

docs/rtpengine.md

@@ -1466,6 +1466,23 @@ If the first given interface has the *BASE:SUFFIX* format then the
 round-robin algorithm is used and will select interfaces with the
 same *BASE* name.
 
+### Alias Names
+
+Interface alias names can be created using the *ALIAS=NAME* syntax. The alias
+must be listed after the primary interface that it references. For example, to
+create an actual logical interface *pub1* and then an alias *pub* for that
+interface:
+
+    interface = pub1/IPv4 pub=pub1
+
+Interface aliases are useful in combination with Redis replication. If an
+interface is referred to via an alias name (e.g. *direction=pub*), then the
+interface's actual name (*pub1* in this example) is propagated into the Redis
+storage and thus to any dependent standby instances. These standby instances
+can then have different address configurations for that interface, which makes
+it possible to facilitate failover with static addressing (for example behind
+an IP load balancer).
+
 ### Legacy Protocols
 
 If you are not using the NG protocol but rather the legacy UDP protocol

include/media_socket.h

@@ -97,6 +97,7 @@ struct intf_config {
 	str				name; // full name (before the '/' separator in config)
 	str				name_base; // if name is "foo:bar", this is "foo"
 	str				name_rr_spec; // if name is "foo:bar", this is "bar"
+	str				alias; // if interface is "foo=bar", this is "bar"
 	struct intf_address		local_address;
 	struct intf_address		advertised_address;
 	unsigned int			port_min, port_max;

t/auto-daemon-tests-intfs.pl

@@ -11,6 +11,7 @@ use POSIX;
 
 autotest_start(qw(--config-file=none -t -1 -i foo/203.0.113.1 -i foo/2001:db8:4321::1
 			-i bar/203.0.113.2 -i bar/2001:db8:4321::2
+			-i blah=foo -i baz=bar
 			-n 2223 -c 12345 -f -L 7 -E -u 2222 --silence-detect=1))
 		or die;
 
@@ -170,4 +171,75 @@ SDP
 
 
 
+offer('intfs selection alias', { direction => [qw(blah baz)] }, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio 2000 RTP/AVP 0
+c=IN IP4 198.51.100.1
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio PORT RTP/AVP 0
+c=IN IP4 203.0.113.2
+a=rtpmap:0 PCMU/8000
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+answer('intfs selection alias', { }, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.2
+s=tester
+t=0 0
+m=audio 3000 RTP/AVP 0
+c=IN IP4 198.51.100.2
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.2
+s=tester
+t=0 0
+m=audio PORT RTP/AVP 0
+c=IN IP4 203.0.113.1
+a=rtpmap:0 PCMU/8000
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+offer('intfs selection and new stream', { }, <<SDP);
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio 2000 RTP/AVP 0
+c=IN IP4 198.51.100.1
+a=sendrecv
+m=audio 2004 RTP/AVP 0
+c=IN IP4 198.51.100.1
+a=sendrecv
+----------------------------------
+v=0
+o=- 1545997027 1 IN IP4 198.51.100.1
+s=tester
+t=0 0
+m=audio PORT RTP/AVP 0
+c=IN IP4 203.0.113.2
+a=rtpmap:0 PCMU/8000
+a=sendrecv
+a=rtcp:PORT
+m=audio PORT RTP/AVP 0
+c=IN IP4 203.0.113.2
+a=rtpmap:0 PCMU/8000
+a=sendrecv
+a=rtcp:PORT
+SDP
+
+
+
+
 done_testing();