Tornado graceful shutdown.

Update the README.

gns3server/__init__.py

@@ -23,6 +23,6 @@
 # or negative for a release candidate or beta (after the base version
 # number has been incremented)
 
-from .module_manager import ModuleManager
-from .server import Server
+#from .module_manager import ModuleManager
+#from .server import Server
 from .version import __version__

gns3server/main.py

@@ -21,7 +21,8 @@ import sys
 import multiprocessing
 import logging
 import tornado.options
-import gns3server
+from .server import Server
+from .version import __version__
 
 # command line options
 from tornado.options import define
@@ -40,7 +41,7 @@ def main():
         multiprocessing.freeze_support()
 
     current_year = datetime.date.today().year
-    print("GNS3 server version {}".format(gns3server.__version__))
+    print("GNS3 server version {}".format(__version__))
     print("Copyright (c) 2007-{} GNS3 Technologies Inc.".format(current_year))
 
     # we only support Python 2 version >= 2.7 and Python 3 version >= 3.3
@@ -59,9 +60,9 @@ def main():
     logging.basicConfig(level=logging.INFO)
 
     from tornado.options import options
-    server = gns3server.Server(options.host,
-                               options.port,
-                               ipc=options.ipc)
+    server = Server(options.host,
+                    options.port,
+                    ipc=options.ipc)
     server.load_modules()
     server.run()
 

gns3server/server.py

@@ -194,6 +194,14 @@ class Server(object):
             log.info("ZeroMQ server listening to 127.0.0.1:{}".format(self._zmq_port))
         return router
 
+    def _shutdown(self):
+        """
+        Shutdowns the I/O loop.
+        """
+
+        ioloop = tornado.ioloop.IOLoop.instance()
+        ioloop.stop()
+
     def _cleanup(self, stop=True):
         """
         Shutdowns any running module processes
@@ -210,13 +218,6 @@ class Server(object):
                 module.terminate()
                 module.join(timeout=1)
 
-        ioloop = tornado.ioloop.IOLoop.instance()
-        # close any fd that would have remained open...
-        for fd in ioloop._handlers.keys():
-            try:
-                os.close(fd)
-            except Exception:
-                pass
-
         if stop:
-            ioloop.stop()
+            ioloop = tornado.ioloop.IOLoop.instance()
+            ioloop.add_callback_from_signal(self._shutdown)