Check if the stream is closed before writing final websocket close packet.

bdarnell · bdarnell · commit ea0291b25626 · 2012-01-21T16:02:28.000-08:00
Closes tornadoweb#390.
diff --git a/tornado/websocket.py b/tornado/websocket.py
@@ -387,8 +387,9 @@ def close(self):
         """Closes the WebSocket connection."""
         if self.client_terminated and self._waiting:
             tornado.ioloop.IOLoop.instance().remove_timeout(self._waiting)
+            self._waiting = None
             self.stream.close()
-        else:
+        elif not self.stream.closed():
             self.stream.write("\xff\x00")
             self._waiting = tornado.ioloop.IOLoop.instance().add_timeout(
                                 time.time() + 5, self._abort)
@@ -603,6 +604,7 @@ def _handle_message(self, opcode, data):
 
     def close(self):
         """Closes the WebSocket connection."""
+        if self.stream.closed(): return
         self._write_frame(True, 0x8, b(""))
         self._started_closing_handshake = True
         self._waiting = tornado.ioloop.IOLoop.instance().add_timeout(time.time() + 5, self._abort)
