65 lines
1.5 KiB
Python
65 lines
1.5 KiB
Python
#
|
|
#
|
|
#
|
|
|
|
from __future__ import absolute_import, division, print_function, unicode_literals
|
|
|
|
from logging import getLogger
|
|
_log = getLogger(__name__)
|
|
del getLogger
|
|
|
|
#
|
|
# As suggested here: http://stackoverflow.com/a/13548984
|
|
#
|
|
|
|
|
|
_suspend_callback = None
|
|
def _suspend():
|
|
if _suspend_callback:
|
|
_log.info("received suspend event from UPower")
|
|
_suspend_callback()
|
|
|
|
|
|
_resume_callback = None
|
|
def _resume():
|
|
if _resume_callback:
|
|
_log.info("received resume event from UPower")
|
|
_resume_callback()
|
|
|
|
|
|
def watch(on_resume_callback, on_suspend_callback):
|
|
"""Register callback for suspend/resume events.
|
|
They are called only if the system DBus is running, and the UPower daemon is available."""
|
|
global _resume_callback, _suspend_callback
|
|
_suspend_callback = on_suspend_callback
|
|
_resume_callback = on_resume_callback
|
|
|
|
|
|
try:
|
|
import dbus
|
|
|
|
_UPOWER_BUS = 'org.freedesktop.UPower'
|
|
_UPOWER_INTERFACE = 'org.freedesktop.UPower'
|
|
|
|
# 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, signal_name='Sleeping',
|
|
dbus_interface=_UPOWER_INTERFACE, bus_name=_UPOWER_BUS)
|
|
|
|
bus.add_signal_receiver(_resume, signal_name='Resuming',
|
|
dbus_interface=_UPOWER_INTERFACE, bus_name=_UPOWER_BUS)
|
|
|
|
_log.info("connected to system dbus, watching for suspend/resume events")
|
|
|
|
except:
|
|
# Either:
|
|
# - the dbus library is not available
|
|
# - the system dbus is not running
|
|
_log.warn("failed to register suspend/resume callbacks")
|
|
pass
|