dbus_service.py

   1 #!/usr/bin/env python
   2
   3 import logging
   4 import socket
   5
   6 import dbus
   7 import dbus.service
   8 from dbus.mainloop.glib import DBusGMainLoop
   9 from gi.repository import GObject
  10
  11 import onoff.common
  12 import onoff.process
  13
  14 logger = logging.getLogger("dbus_service")
  15
  16 def dbus_socket_pair():
  17     """Create a socket pair where the latter end is suitable for dbus.
  18     @rtype: (socket, dbus.types.UnixFd)
  19     """
  20     s1, s2 = socket.socketpair()
  21     s3 = dbus.types.UnixFd(s2)
  22     s2.close()
  23     return s1, s3
  24
  25 class OnoffControl(dbus.service.Object):
  26     domain = "de.subdivi.onoff0"
  27     path = "/de/subdivi/onoff0"
  28
  29     def __init__(self, bus, name, device):
  30         busname = dbus.service.BusName(self.domain, bus=bus)
  31         dbus.service.Object.__init__(self, busname, "%s/%s" % (self.path, name))
  32         self.device = device
  33         device.notify.add(self.changestate)
  34         self.usecount = 0
  35
  36     @dbus.service.signal(domain, signature="q")
  37     def changestate(self, st):
  38         logger.debug("emitting state %d", st)
  39
  40     @dbus.service.method(domain, out_signature="q")
  41     def state(self):
  42         return self.device.state
  43
  44     @dbus.service.method(domain, in_signature="q", out_signature="q")
  45     def activatetime(self, duration):
  46         logger.info("activatetime %d", duration)
  47         GObject.timeout_add(duration * 1000, self.unuse)
  48         return self.use()
  49
  50     @dbus.service.method(domain, in_signature="q", out_signature="qh")
  51     def activatefd(self, duration):
  52         logger.info("activatefd duration %d", duration)
  53         notifyfd, retfd = dbus_socket_pair()
  54         def callback(fd, _):
  55             logger.info("fd %d completed", fd.fileno())
  56             fd.close()
  57             GObject.timeout_add(duration * 1000, self.unuse)
  58             return False
  59         GObject.io_add_watch(notifyfd, GObject.IO_HUP|GObject.IO_ERR, callback)
  60         return (self.use(), retfd)
  61
  62     def use(self):
  63         self.usecount += 1
  64         if self.usecount <= 1:
  65             self.device.activate()
  66         return self.device.state
  67
  68     def unuse(self):
  69         self.usecount -= 1
  70         if not self.usecount:
  71             self.device.deactivate()
  72         else:
  73             logger.debug("%d users left", self.usecount)
  74         return False
  75
  76
  77 def main():
  78     logging.basicConfig()
  79     logging.getLogger().setLevel(logging.DEBUG)
  80     DBusGMainLoop(set_as_default=True)
  81     bus = dbus.SessionBus()
  82     dev = onoff.process.OnoffProcess(["redshift"], 3)
  83     dev = onoff.common.InvertedDevice(dev)
  84     OnoffControl(bus, "redshift", dev)
  85     GObject.MainLoop().run()
  86
  87 if __name__ == "__main__":
  88     main()