4 import xml.parsers.expat
8 from gi.repository import GObject
10 logger = logging.getLogger("onoff.dbusutils")
12 object_prefix = "/de/subdivi/onoff0"
13 default_busname = "de.subdivi.onoff0"
15 dbus_options = argparse.ArgumentParser(add_help=False)
16 dbus_options.add_argument("--bus", default="session",
17 choices=("system", "session"),
18 help="which bus to use (default: %(default)s)")
19 dbus_options.add_argument("--busname", type=str, default=default_busname,
20 help="which busname (i.e. client) to use " +
21 "(default: %(default)s)")
22 dbus_options.add_argument("--device", type=str,
23 help="which device to control")
25 def get_dbus(namespace):
27 @param namespace: a namespace returned from a dbus_options argument parser
29 @returns: the requested bus
31 if namespace.bus == "session":
32 return dbus.SessionBus()
33 elif namespace.bus == "system":
34 return dbus.SystemBus()
36 raise AssertionError("namespace.bus %r is neither session nor system",
39 def get_dbus_proxy(namespace):
41 @param namespace: a namespace returned from a dbus_options argument parser
42 @returns: a dbus object proxy
44 bus = get_dbus(namespace)
45 if not namespace.device:
46 raise ValueError("no --device given")
47 objname = "%s/%s" % (object_prefix, namespace.device)
48 return bus.get_object(namespace.busname, objname)
51 """Create a socket pair where the latter end is already wrapped for
52 transmission over dbus.
54 @rtype: (socket, dbus.types.UnixFd)
56 s1, s2 = socket.socketpair()
57 s3 = dbus.types.UnixFd(s2)
61 def list_objects(bus, busname, path=None):
62 """List objects on the given bus and busname starting with path. Only the
63 trailing components after the slash are returned.
67 @type path: None or str
68 @param path: prefix for searching objects. Defaults to
69 dbusutils.object_prefix.
71 @returns: the trailing components of the objects found
75 xmlstring = bus.get_object(busname, path).Introspect()
76 parser = xml.parsers.expat.ParserCreate()
78 def start_element(name, attrs):
86 parser.StartElementHandler = start_element
87 parser.Parse(xmlstring)
90 class OnoffControl(dbus.service.Object):
91 domain = default_busname
94 def __init__(self, bus, name, device):
98 @type device: OnoffDevice
100 busname = dbus.service.BusName(self.domain, bus=bus)
101 dbus.service.Object.__init__(self, busname, "%s/%s" % (self.path, name))
104 device.notify.add(self.changestate)
106 @dbus.service.signal(domain, signature="q")
107 def changestate(self, state):
108 logger.debug("emitting state %d", state)
110 @dbus.service.method(domain, out_signature="q")
112 return self.device.state
114 @dbus.service.method(domain, in_signature="q", out_signature="q")
115 def activatetime(self, duration):
116 """Activate the device for a given number of seconds."""
117 logger.info("activatetime %d", duration)
118 GObject.timeout_add(duration * 1000, self.unuse)
121 @dbus.service.method(domain, in_signature="", out_signature="qh")
122 def activatefd(self):
123 """Activate a device until the returned file descriptor is closed."""
124 logger.info("activatefd")
125 notifyfd, retfd = socketpair()
127 logger.info("fd %d completed", fd.fileno())
131 GObject.io_add_watch(notifyfd, GObject.IO_HUP|GObject.IO_ERR, callback)
132 return (self.use(), retfd)
136 if self.usecount <= 1:
137 self.device.activate()
138 return self.device.state
142 if not self.usecount:
143 self.device.deactivate()
145 logger.debug("%d users left", self.usecount)