make call_lookup_udp() remember viabranches like call_update_udp()

daemon/call.c

@@ -1591,7 +1591,7 @@ restart:
 		rwlock_unlock_r(&m->hashlock);
 	}
 
-	if (viabranch && !g_hash_table_lookup(c->branches, viabranch))
+	if (viabranch && *viabranch && !g_hash_table_lookup(c->branches, viabranch))
 		g_hash_table_insert(c->branches, call_strdup(c, viabranch),
 		(void *) 0x1);
 
@@ -1688,31 +1688,29 @@ char *call_lookup_udp(const char **out, struct callmaster *m) {
 	struct stream st;
 	int num;
 	char *ret;
+	const char *branch;
 
 	rwlock_lock_r(&m->hashlock);
 	c = g_hash_table_lookup(m->callhash, out[RE_UDP_UL_CALLID]);
 	if (c)
 		mutex_lock(&c->lock);
-	else
-		goto not_found;
-
-	if (!out[RE_UDP_UL_VIABRANCH] || !*out[RE_UDP_UL_VIABRANCH])
-		goto skip_branch;
-
-	if (!g_hash_table_lookup(c->branches, out[RE_UDP_UL_VIABRANCH])) {
-		mutex_unlock(&c->lock);
-not_found:
+	else {
 		rwlock_unlock_r(&m->hashlock);
 		mylog(LOG_WARNING, LOG_PREFIX_CI "Got UDP LOOKUP for unknown call-id or unknown via-branch",
 			out[RE_UDP_UL_CALLID], out[RE_UDP_UL_VIABRANCH]);
 		xasprintf(&ret, "%s 0 " IPF "\n", out[RE_UDP_COOKIE], IPP(m->conf.ipv4));
 		return ret;
 	}
-skip_branch:
+
 	obj_hold(c);
 	rwlock_unlock_r(&m->hashlock);
 
-	log_info = out[RE_UDP_UL_VIABRANCH];
+	branch = out[RE_UDP_UL_VIABRANCH];
+	if (branch && *branch && !g_hash_table_lookup(c->branches, branch))
+		g_hash_table_insert(c->branches, call_strdup(c, branch),
+		(void *) 0x1);
+
+	log_info = branch;
 	c->called_agent = "UNKNOWN(udp)";
 
 	if (addr_parse_udp(&st, out))