Avoid infinite recursion when exiting a service connected to LS

Finalize had a logging call between the termination of the socket and
the marking of the client as disconnected; therefore the logging
module attempted to send the log to LS, but this incurred in an error
as the socket was close. The new error was then logged again, causing
the infinte recursion.

With the logging call after the client has been marked as
disconnected, execute_rpc for the log call returns early without
errors.

Author: stefano-maggiolo

cms/io/rpc.py

@@ -3,7 +3,7 @@
 
 # Contest Management System - http://cms-dev.github.io/
 # Copyright © 2010-2013 Giovanni Mascellani <mascellani@poisson.phc.unipi.it>
-# Copyright © 2010-2015 Stefano Maggiolo <s.maggiolo@gmail.com>
+# Copyright © 2010-2018 Stefano Maggiolo <s.maggiolo@gmail.com>
 # Copyright © 2010-2012 Matteo Boscariol <boscarim@hotmail.com>
 # Copyright © 2013-2017 Luca Wehrstedt <luca.wehrstedt@gmail.com>
 #
@@ -185,15 +185,17 @@ def finalize(self, reason=""):
         if not self.connected:
             return
 
-        logger.info("Terminated connection with %s (local address: %s): %s",
-                    self._repr_remote(), self._local_address, reason)
+        local_address = self._local_address
 
         self._socket = None
         self._reader = None
         self._writer = None
         self._local_address = None
         self._connection_event.clear()
 
+        logger.info("Terminated connection with %s (local address: %s): %s",
+                    self._repr_remote(), local_address, reason)
+
         for handler in self._on_disconnect_handlers:
             gevent.spawn(handler)