rpc: If the socket is closed by peer, endpoint stop the serve.

If client does socket.close() the serve will be non-wait looping.
So must stop the serve of endpoint that received 0 byte packet.

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

ryu/lib/rpc.py

@@ -115,6 +115,7 @@ class EndPoint(object):
         self._notifications = deque()
         self._responses = {}
         self._incoming = 0  # number of incoming messages in our queues
+        self.closed_by_peer = False
 
     def selectable(self):
         rlist = [self._sock]
@@ -142,7 +143,7 @@ class EndPoint(object):
         select.select(rlist, wlist, rlist + wlist)
 
     def serve(self):
-        while True:
+        while not self.closed_by_peer:
             self.block()
             self.process()
 
@@ -182,6 +183,9 @@ class EndPoint(object):
             except IOError:
                 packet = None
             if not packet:
+                if packet is not None:
+                    # socket closed by peer
+                    self.closed_by_peer = True
                 break
             self._encoder.get_and_dispatch_messages(packet, self._table)
         return self._incoming > 0