s/volume./block./ (udev_filter_func): new function for filtering D-BUS

    messages from udev (setup_udev_listener): setup filter for udev
    messages (hal_monitor_enter): Listen to D-BUS messages
Use global sysfs path (device_hotplug_add): Use global sysfs path
    (device_hotplug_remove): Use global sysfs path (drivers_collect): Use
    global sysfs path (mainloop_integration): Save D-BUS connection object
    for later use (main): Get sysfs mount path once and for all
Add dbus_connection and sysfs_mount_path as extern variables
new function (filter_function): add check for Device.QueryCapability
Minor formatting stuff
Crude example of volume manager now that we got udev integration in place.
    It doesn't really mount anything but prints out when it should mount.
    You'll need a very recent udev from BitKeeper with D-BUS enabled (got
    the patch accepted today)

1 files changed, 99 insertions, 0 deletions

diff --git a/examples/volumed/volumed.py b/examples/volumed/volumed.py
new file mode 100755
index 00000000..5ace4793
--- /dev/null
+++ b/examples/volumed/volumed.py
@@ -0,0 +1,99 @@
+#!/usr/bin/python
+
+import dbus
+import gtk
+import time
+
+# This is just a very very crude example of what a volume daemon could
+# look like... It actually doesn't mount anything; it only prints out
+# messages when it should mount/unmount stuff.
+#
+# A volume daemon should also support optical and floppy disks, it should
+# handle multi-session cdroms and much more. Maybe someone will write
+# this one day...
+#
+
+def get_mount_point(udi, device_name):
+    """Given a the UDI for a device and the name of the device file,
+    determine a name for the mount point"""
+    return '/mnt/somewhere/unique%f'%(time.time())
+
+def attempt_mount(udi):
+    """See if a block device has enough information so we can mount it"""
+    dobj = hal_service.get_object(udi, 'org.freedesktop.Hal.Device')
+    if (not mount_dict.has_key(udi)) and dobj.PropertyExists('block.device'):
+        device = dobj.GetProperty('block.device')
+        mount_point = get_mount_point(udi, device)
+        print "mounting device=%s at %s udi=%s"%(device, mount_point, udi)
+        mount_dict[udi] = mount_point
+
+def unmount(udi):
+    """Unmount a device"""
+    mount_point = mount_dict[udi]
+    print "unmounting %s"%mount_point
+    del mount_dict[udi]
+
+def device_changed(dbus_if, member, svc, obj_path, message):
+    """Called when properties on a HAL device changes"""
+    print member
+    udi = obj_path
+    if udi in vol_list:
+        attempt_mount(udi)
+
+def gdl_changed(dbus_if, member, svc, obj_path, message):
+    """Called when a HAL device is added, removed or it got a
+    new capability"""
+    print member
+    if member=='NewCapability':
+        [udi, cap] = message.get_args_list()
+        if cap=='volume':
+            if not udi in vol_list:
+                vol_list.append(udi)
+                bus.add_signal_receiver(device_changed,
+                                        'org.freedesktop.Hal.Device',
+                                        'org.freedesktop.Hal',
+                                        udi)
+                attempt_mount(udi)
+                
+        print "  %s %s"%(cap,udi)
+
+    elif member=='DeviceRemoved':
+        [udi] = message.get_args_list()
+        if udi in vol_list:
+            vol_list.remove(udi)
+            bus.remove_signal_receiver(device_changed,
+                                       'org.freedesktop.Hal.Device',
+                                       'org.freedesktop.Hal',
+                                       udi)
+            unmount(udi)
+            
+    elif member=='DeviceAdded':
+        [udi] = message.get_args_list()
+        dobj = hal_service.get_object(udi, 'org.freedesktop.Hal.Device')
+        if dobj.QueryCapability('volume'):
+            vol_list.append(udi)
+            bus.add_signal_receiver(device_changed,
+                                    'org.freedesktop.Hal.Device',
+                                    'org.freedesktop.Hal',
+                                    udi)
+            attempt_mount(udi)
+
+def main():
+    """Entry point"""
+    global bus, hal_service, vol_list, mount_dict
+
+    vol_list = []
+    mount_dict = {}
+    
+    bus = dbus.Bus(dbus.Bus.TYPE_SYSTEM)
+    hal_service = bus.get_service('org.freedesktop.Hal')
+
+    bus.add_signal_receiver(gdl_changed,
+                            'org.freedesktop.Hal.Manager',
+                            'org.freedesktop.Hal',
+                            '/org/freedesktop/Hal/Manager')
+
+    gtk.mainloop()
+
+if __name__=='__main__':
+    main()