blob: 18fe3408b62f7b8690b5bb722464bd29429814e2 [file] [log] [blame]
# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import common, logging, os, time
from autotest_lib.client.common_lib import error
from autotest_lib.client.common_lib import utils
from autotest_lib.client.cros import constants
# Log messages used to signal when we're restarting UI. Used to detect
# crashes by cros_ui_test.UITest.
UI_RESTART_ATTEMPT_MSG = ' Attempting StopSession...'
UI_RESTART_COMPLETE_MSG = ' StopSession complete.'
RESTART_UI_TIMEOUT = 90 # longer because we may be crash dumping now.
def get_chrome_session_ident(host=None):
"""Return an identifier that changes whenever Chrome restarts.
This function returns a value that is unique to the most
recently started Chrome process; the returned value changes
each time Chrome restarts and displays the login screen. The
change in the value can be used to detect a successful Chrome
Note that uniqueness is only guaranteed until the host reboots.
host: If not None, a host object on which to test Chrome
state, rather than running commands on the local host.
if host:
def wait_for_chrome_ready(old_session, host=None,
"""Wait until a new Chrome login prompt is on screen and ready.
The standard formula to check whether the prompt has appeared yet
is with a pattern like the following:
session = get_chrome_session_ident()
old_session: identifier for the login prompt prior to
restarting Chrome.
host: If not None, a host object on which to test Chrome
state, rather than running commands on the local host.
timeout: float number of seconds to wait
TimeoutError: Login prompt didn't get up before timeout
condition=lambda: old_session != get_chrome_session_ident(host),
exception=utils.TimeoutError('Timed out waiting for login prompt'),
timeout=timeout, sleep_interval=1.0)
def stop_and_wait_for_chrome_to_exit(timeout_secs=40):
"""Stops the UI and waits for chrome to exit.
Stops the UI and waits for all chrome processes to exit or until
timeout_secs is reached.
timeout_secs: float number of seconds to wait.
True upon successfully stopping the UI and all chrome processes exiting.
False otherwise.
status = stop(allow_fail=True)
if status:
logging.error('stop ui returned non-zero status: %s', status)
return False
start_time = time.time()
while time.time() - start_time < timeout_secs:
status = utils.system('pgrep chrome', ignore_status=True)
if status == 1: return True
logging.error('stop ui failed to stop chrome within %s seconds',
return False
def stop(allow_fail=False):
return utils.stop_service("ui", ignore_status=allow_fail)
def start(allow_fail=False, wait_for_login_prompt=True):
"""Start the login manager and wait for the prompt to show up."""
session = get_chrome_session_ident()
result = utils.start_service("ui", ignore_status=allow_fail)
# If allow_fail is set, the caller might be calling us when the UI job
# is already running. In that case, the above command fails.
if result == 0 and wait_for_login_prompt:
return result
def restart(report_stop_failure=False):
"""Restart the session manager.
- If the user is logged in, the session will be terminated.
- If the UI is currently down, just go ahead and bring it up unless the
caller has requested that a failure to stop be reported.
- To ensure all processes are up and ready, this function will wait
for the login prompt to show up and be marked as visible.
@param report_stop_failure: False by default, set to True if you care about
the UI being up at the time of call and
successfully torn down by this call.
session = get_chrome_session_ident()
# Log what we're about to do to /var/log/messages. Used to log crashes later
# in cleanup by cros_ui_test.UITest.
utils.system('logger "%s"' % UI_RESTART_ATTEMPT_MSG)
if stop(allow_fail=not report_stop_failure) != 0:
raise error.TestError('Could not stop session')
# Wait for login prompt to appear to indicate that all processes are
# up and running again.
utils.system('logger "%s"' % UI_RESTART_COMPLETE_MSG)
def nuke():
"""Nuke the login manager, waiting for it to restart."""
restart(lambda: utils.nuke_process_by_name(constants.SESSION_MANAGER))
def is_up():
"""Return True if the UI is up, False if not."""
return utils.get_service_pid('ui')!=0
def clear_respawn_state():
"""Removes bookkeeping related to respawning crashed UI."""
for filename in [constants.UI_RESPAWN_TIMESTAMPS_FILE,
except OSError:
pass # It's already gone.