no data means bad read

git-svn-id: http://svn.freeswitch.org/svn/freeswitch/trunk@2703 d0543943-73ff-0310-b7d9-9358b9ac24b2

src/mod/endpoints/mod_sofia/mod_sofia.c

@@ -908,9 +908,14 @@ static switch_status_t sofia_read_frame(switch_core_session_t *session, switch_f
 		}
 
 	} 
-
+	
 	switch_clear_flag_locked(tech_pvt, TFLAG_READING);
 
+	if (tech_pvt->read_frame.datalen == 0) {
+		*frame = NULL;
+		return SWITCH_STATUS_GENERR;
+	}
+
 	*frame = &tech_pvt->read_frame;
 
 	return SWITCH_STATUS_SUCCESS;