84 lines
2.4 KiB
Python
84 lines
2.4 KiB
Python
# -*- python-mode -*-
|
|
|
|
## Copyright (C) 2012-2013 Daniel Pavel
|
|
##
|
|
## This program is free software; you can redistribute it and/or modify
|
|
## it under the terms of the GNU General Public License as published by
|
|
## the Free Software Foundation; either version 2 of the License, or
|
|
## (at your option) any later version.
|
|
##
|
|
## This program is distributed in the hope that it will be useful,
|
|
## but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
## GNU General Public License for more details.
|
|
##
|
|
## You should have received a copy of the GNU General Public License along
|
|
## with this program; if not, write to the Free Software Foundation, Inc.,
|
|
## 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
|
|
|
|
import logging
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
#
|
|
# As suggested here: http://stackoverflow.com/a/13548984
|
|
#
|
|
|
|
_suspend_callback = None
|
|
|
|
|
|
def _suspend():
|
|
if _suspend_callback:
|
|
if logger.isEnabledFor(logging.INFO):
|
|
logger.info("received suspend event")
|
|
_suspend_callback()
|
|
|
|
|
|
_resume_callback = None
|
|
|
|
|
|
def _resume():
|
|
if _resume_callback:
|
|
if logger.isEnabledFor(logging.INFO):
|
|
logger.info("received resume event")
|
|
_resume_callback()
|
|
|
|
|
|
def _suspend_or_resume(suspend):
|
|
_suspend() if suspend else _resume()
|
|
|
|
|
|
def watch(on_resume_callback=None, on_suspend_callback=None):
|
|
"""Register callback for suspend/resume events.
|
|
They are called only if the system DBus is running, and the Login daemon is available."""
|
|
global _resume_callback, _suspend_callback
|
|
_suspend_callback = on_suspend_callback
|
|
_resume_callback = on_resume_callback
|
|
|
|
|
|
try:
|
|
import dbus
|
|
|
|
_LOGIND_BUS = "org.freedesktop.login1"
|
|
_LOGIND_INTERFACE = "org.freedesktop.login1.Manager"
|
|
|
|
# integration into the main GLib loop
|
|
from dbus.mainloop.glib import DBusGMainLoop
|
|
|
|
DBusGMainLoop(set_as_default=True)
|
|
|
|
bus = dbus.SystemBus()
|
|
assert bus
|
|
|
|
bus.add_signal_receiver(_suspend_or_resume, "PrepareForSleep", dbus_interface=_LOGIND_INTERFACE, bus_name=_LOGIND_BUS)
|
|
|
|
if logger.isEnabledFor(logging.INFO):
|
|
logger.info("connected to system dbus, watching for suspend/resume events")
|
|
|
|
except Exception:
|
|
# Either:
|
|
# - the dbus library is not available
|
|
# - the system dbus is not running
|
|
logger.warning("failed to register suspend/resume callbacks")
|
|
pass
|