Due to recent changes tag will no longer be NULL if not present so we have to use ast_strlen_zero to see if it's actually blank.

(closes issue #12061)
Reported by: flefoll
Patches:
      chan_sip.c.br14.patch_pedantic_no_totag uploaded by flefoll (license 244)


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@104082 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_sip.c

@@ -4567,7 +4567,7 @@ static struct sip_pvt *find_call(struct sip_request *req, struct sockaddr_in *si
 			found = (!strcmp(p->callid, callid));
 		else 
 			found = (!strcmp(p->callid, callid) && 
-			(!pedanticsipchecking || !tag || ast_strlen_zero(p->theirtag) || !strcmp(p->theirtag, tag))) ;
+			(!pedanticsipchecking || ast_strlen_zero(tag) || ast_strlen_zero(p->theirtag) || !strcmp(p->theirtag, tag))) ;
 
 		if (option_debug > 4)
 			ast_log(LOG_DEBUG, "= %s Their Call ID: %s Their Tag %s Our tag: %s\n", found ? "Found" : "No match", p->callid, p->theirtag, p->tag);