server: fix 'deleted config' race

When a config is deleted, goroutine for FSMHandler.h.Dying becomes
active. sendMessageloop must send notifcation before dying. So it
should not check Dying(). After sending notificaiton, it closes the
conneciton and return. It makes sure that rx goroutine will die too.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>

1 files changed, 4 insertions, 3 deletions

diff --git a/server/fsm.go b/server/fsm.go
index 5c93fce6..b70f0860 100644
--- a/server/fsm.go
+++ b/server/fsm.go
@@ -388,9 +388,10 @@ func (h *FSMHandler) sendMessageloop() error {
 	conn := h.conn
 	fsm := h.fsm
 	for {
+		// this function doesn't check Dying() because we
+		// can't die before sending notificaiton. After
+		// sending notification, we'll die.
 		select {
-		case <-h.t.Dying():
-			return nil
 		case m := <-h.outgoing:
 			b, _ := m.Serialize()
 			_, err := conn.Write(b)
@@ -407,6 +408,7 @@ func (h *FSMHandler) sendMessageloop() error {
 
 			if m.Header.Type == bgp.BGP_MSG_NOTIFICATION {
 				h.errorCh <- true
+				conn.Close()
 				return nil
 			}
 		case <-fsm.keepaliveTicker.C:
@@ -445,7 +447,6 @@ func (h *FSMHandler) established() bgp.FSMState {
 			h.t.Kill(nil)
 			return bgp.BGP_FSM_IDLE
 		case <-h.t.Dying():
-			h.conn.Close()
 			return 0
 		}
 	}