fix: stem: Exit on failure connecting to control port

because when trying to connect to an external tor (chutney), it does
not make sense to start own tor.
Also log how the connection has been made.

sbws/util/stem.py

@@ -110,8 +110,9 @@ def _init_controller_port(port):
         c = Controller.from_port(port=port)
         c.authenticate()
     except (IncorrectSocketType, SocketError):
-        return None
+        fail_hard("Unable to connect to control port %s.", port)
     # TODO: Allow for auth via more than just CookieAuthentication
+    log.info("Connected to tor via port %s", port)
     return c
 
 
@@ -127,6 +128,7 @@ def _init_controller_socket(socket):
         log.exception("Error initting controller socket: %s", e)
         return None
     # TODO: Allow for auth via more than just CookieAuthentication
+    log.info("Connected to tor via socket %s", socket)
     return c
 
 
@@ -233,6 +235,7 @@ def launch_tor(conf):
             torrc, init_msg_handler=log.debug, take_ownership=True)
     except Exception as e:
         fail_hard('Error trying to launch tor: %s', e)
+    log.info("Started own tor.")
     # And return a controller to it
     cont = _init_controller_socket(conf.getpath('tor', 'control_socket'))
     # Set options that can fail at runtime
@@ -240,8 +243,7 @@ def launch_tor(conf):
     # Set runtime options
     set_torrc_runtime_options(cont)
 
-    log.info('Started and connected to Tor %s via %s', cont.get_version(),
-             conf.getpath('tor', 'control_socket'))
+    log.info('Started or connected to Tor %s.', cont.get_version())
     return cont