Re: [RFC BlueZ 3/3] core: Add Interfaces property to org.bluez.Device

[Marcel Holtmann <marcel@holtmann.org>]

Hi Luiz,

> >> > On Tue, Mar 6, 2012 at 8:07 AM, Luiz Augusto von Dentz
> >> > <luiz.dentz@gmail.com> wrote:
> >> >> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> >> >>
> >> >> This enables applications to be able to detect when an interface is
> >> >> enabled/disabled without depending on UUIDs.
> >> >> ---
> >> >>  doc/device-api.txt |    4 ++++
> >> >>  src/device.c       |   27 ++++++++++++++++++++++-----
> >> >>  2 files changed, 26 insertions(+), 5 deletions(-)
> >> >
> >> > I thought it was possible to achieve this by using D-Bus listeners?
> >> > E.g. similar to g_dbus_add_service_watch()
> >>
> >> Afaik there is no such thing as introspection data changed or anything
> >> like that, we could in theory have local listeners, but at least in
> >> BlueZ there is no much use for them since it is not really dynamic
> >> after drivers are loaded, but perhaps for oFono and others it could be
> >> useful to have some way to watch when interfaces changes.
> >>
> >> In case of oFono it does that by having e.g.
> >> ofono_modem_add_interface/ofono_modem_remove_interface.
> >>
> >> > What happens when the interface is unregistered with
> >> > g_dbus_unregister_interface() ?
> >>
> >> This should only be the case when removing the object so the driver
> >> .remove is called which then calls g_dbus_unregister_interface.
> >
> > I was not planning to add this to our gdbus code and focus on getting
> > this right for ELL. However look into the D-Bus ObjectManager
> > specification since that is what you want actually.
> 
> So the way forward is to implement ObjectManager? We could have that
> without breaking any API, but I guess it would make sense to change
> API such as the manager to take advantage of the ObjectManager.

have a look at ObjectManager and how much it takes for us to use it. I
know that the properties will be a bit of problem, but maybe still worth
it to start supporting it.

> Btw what is ELL?

http://git.kernel.org/?p=libs/ell/ell.git

Regards

Marcel