Allow sbws to use an already-existing tor process, with warning

def run_speedtest(args, conf):

    controller, _ = stem_utils.init_controller(

        path=conf['tor']['control_socket'])

    if not controller:

        controller = stem_utils.launch_tor(conf)

    else:

        log.warning(

            'Is sbws already running? '

            'We found an existing Tor process at %s. We are not going to '

            'launch Tor, nor are we going to try to configure it to behave '

            'like we expect. This might work okay, but it also might not. '

            'If you experience problems, you should try letting sbws launch '

            'Tor for itself. The ability to use an already running Tor only '

            'exists for sbws developers. It is expected to be broken and may '

            'even lead to messed up results.', conf['tor']['control_socket'])

        time.sleep(15)

    assert stem_utils.is_controller_okay(controller)

    cb = CB(args, conf, controller)

    rl = RelayList(args, conf, controller)

    rd = ResultDump(args, conf, end_event)

def init_controller(port=None, path=None, set_custom_stream_settings=True):

    # NOTE: we do not currently support a control port even though the rest of

    # this function will pretend like port could be set.

    assert port is None

    # make sure only one is set

    assert port is not None or path is not None

    assert not (port is not None and path is not None)