reverses minor sip registration regression

reverses the changes caused by issue #15539. The
issue reported was expected behavior.

(issue #15539)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.6.1@235135 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -10906,13 +10906,20 @@ static int transmit_register(struct sip_registry *r, int sipmethod, const char *
 		else
 			snprintf(to, sizeof(to), "<sip:%s@%s>", r->username, p->tohost);
 	}
-
-	/* Host is what we are registered to, regardless if a domain exists in the username */
-	if (r->portno && r->portno != STANDARD_SIP_PORT)
-		snprintf(addr, sizeof(addr), "sip:%s:%d", r->hostname, r->portno);
-	else
-		snprintf(addr, sizeof(addr), "sip:%s", r->hostname);
-
+	
+	/* Fromdomain is what we are registering to, regardless of actual
+	   host name from SRV */
+	if (!ast_strlen_zero(p->fromdomain)) {
+		if (r->portno && r->portno != STANDARD_SIP_PORT)
+			snprintf(addr, sizeof(addr), "sip:%s:%d", p->fromdomain, r->portno);
+		else
+			snprintf(addr, sizeof(addr), "sip:%s", p->fromdomain);
+	} else {
+		if (r->portno && r->portno != STANDARD_SIP_PORT)
+			snprintf(addr, sizeof(addr), "sip:%s:%d", r->hostname, r->portno);
+		else
+			snprintf(addr, sizeof(addr), "sip:%s", r->hostname);
+	}
 	ast_string_field_set(p, uri, addr);
 
 	p->branch ^= ast_random();