Ensuring server cleanup on OS signals

atexit won't run registered functions for SIGTERM which we send to the server.
This prevents clean shutdown.

Also making sure that the server logfiles are deleted as well.

python/ycm/server/default_settings.json

@@ -28,6 +28,7 @@
   },
   "server_use_vim_stdout": 0,
   "server_log_level": "info",
+  "server_keep_logfiles": 0,
   "auto_start_csharp_server": 1,
   "auto_stop_csharp_server": 1,
   "csharp_server_port": 2000

python/ycm/server/handlers.py

@@ -197,7 +197,7 @@ def _GetCompleterForRequestData( request_data ):
 
 
 @atexit.register
-def _ServerShutdown():
+def ServerShutdown():
   LOGGER.info( 'Server shutting down' )
   if SERVER_STATE:
     SERVER_STATE.Shutdown()

python/ycm/server/ycmd.py

@@ -25,6 +25,7 @@ import logging
 import json
 import argparse
 import waitress
+import signal
 from ycm import user_options_store
 from ycm import extra_conf_store
 
@@ -34,6 +35,20 @@ def YcmCoreSanityCheck():
     raise RuntimeError( 'ycm_core already imported, ycmd has a bug!' )
 
 
+# We need to manually call ServerShutdown for the signals that turn down ycmd
+# because atexit won't handle them.
+def SetUpSignalHandler():
+  def SignalHandler():
+    import handlers
+    handlers.ServerShutdown()
+
+  for sig in [ signal.SIGTERM,
+               signal.SIGINT,
+               signal.SIGHUP,
+               signal.SIGQUIT ]:
+    signal.signal( sig, SignalHandler )
+
+
 def Main():
   parser = argparse.ArgumentParser()
   parser.add_argument( '--host', type = str, default = 'localhost',
@@ -69,6 +84,7 @@ def Main():
   # preload has executed.
   import handlers
   handlers.UpdateUserOptions( options )
+  SetUpSignalHandler()
   waitress.serve( handlers.app,
                   host = args.host,
                   port = args.port,

python/ycm/youcompleteme.py

@@ -205,6 +205,12 @@ class YouCompleteMe( object ):
       self._server_popen.terminate()
     os.remove( self._temp_options_filename )
 
+    if not self._user_options[ 'server_keep_logfiles' ]:
+      if self._server_stderr:
+        os.remove( self._server_stderr )
+      if self._server_stdout:
+        os.remove( self._server_stdout )
+
 
   def OnCurrentIdentifierFinished( self ):
     if not self._IsServerAlive():