Addind the mechanisms to cleanup eNB when SCTP connection is terminated.

srsepc/src/mme/mme.cc

@@ -136,9 +136,22 @@ mme::run_thread()
       m_s1ap_log.debug("Socket timeout reached");
     }
     else{
-      pdu->N_bytes = rd_sz;
-      m_s1ap_log.info("Received S1AP msg. Size: %d\n", pdu->N_bytes);
-      m_s1ap.handle_s1ap_rx_pdu(pdu,&sri);
+      if(msg_flags & MSG_NOTIFICATION)
+      {
+        //Received notification
+        m_s1ap_log.console("SCTP Notification %d\n", ((union sctp_notification*)pdu->msg)->sn_header.sn_type);
+        if (((union sctp_notification*)pdu->msg)->sn_header.sn_type == SCTP_SHUTDOWN_EVENT)
+        {
+          m_s1ap_log.console("SCTP Association Gracefully Shutdown\n");
+        }
+      }
+      else
+      { 
+        //Received data
+        pdu->N_bytes = rd_sz;
+        m_s1ap_log.info("Received S1AP msg. Size: %d\n", pdu->N_bytes);
+        m_s1ap.handle_s1ap_rx_pdu(pdu,&sri);
+      }
     }
   }
   return;

srsepc/src/mme/s1ap.cc

@@ -62,7 +62,7 @@ s1ap::stop()
   std::map<uint16_t,enb_ctx_t*>::iterator it = m_active_enbs.begin();
   while(it!=m_active_enbs.end())
   {
-    //print_enb_ctx_info(*it->second);
+    print_enb_ctx_info(*it->second);
     delete it->second;
     m_active_enbs.erase(it++);
   }
@@ -91,8 +91,10 @@ s1ap::enb_listen()
   }
 
   //Sets the data_io_event to be able to use sendrecv_info
+  //Subscribes to the SCTP_SHUTDOWN event, to handle graceful shutdown
   bzero (&evnts, sizeof (evnts)) ;
   evnts.sctp_data_io_event = 1;
+  evnts.sctp_shutdown_event=1;
   if(setsockopt(sock_fd, IPPROTO_SCTP, SCTP_EVENTS, &evnts, sizeof (evnts))){
     m_s1ap_log->console("Subscribing to sctp_data_io_events failed\n");
     return -1;