ignore CANCEL of incoming requests after we send a final response. Patch by me and Kai Vehmanen.

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@4213 d0543943-73ff-0310-b7d9-9358b9ac24b2

libs/sofia-sip/libsofia-sip-ua/nua/nua_session.c

@@ -2210,16 +2210,15 @@ int process_cancel(nua_server_request_t *sr,
   nua_session_usage_t *ss = nua_dialog_usage_private(sr->sr_usage);
   msg_t *cancel = nta_incoming_getrequest_ackcancel(irq);
 
-  assert(nta_incoming_status(irq) < 200);
-  assert(nua_server_request_is_pending(sr));
-  assert(ss); assert(ss == nua_session_usage_get(nh->nh_ds)); (void)ss;
-
+  if (nta_incoming_status(irq) < 200 && nua_server_request_is_pending(sr) &&
+	  ss && (ss == nua_session_usage_get(nh->nh_ds))) {
     nua_stack_event(nh->nh_nua, nh, cancel, nua_i_cancel, SIP_200_OK, NULL);
 
     SR_STATUS1(sr, SIP_487_REQUEST_TERMINATED);
 
     nua_server_respond(sr, NULL);
     nua_server_report(sr);
+  }
 
   return 0;
 }