[packagekit] Run pkclient action from thread

[Richard Hughes]

On 16 April 2010 19:00, Matthias Klumpp <matthias at nlinux.org> wrote:
> This is a little bit difficult... I have written a library which makes use
> of PackageKit in several ways (search for packages/files, resolve names
> etc.). It also runs a lot of other stuff, which blocks the GUI application
> that makes use of the lib as long as these processes run.

That's exactly why the PkClient is asynchronous. You don't have to run
it in a thread to get a non-blocking UI, you just connect up the Gio
completion and then do other stuff while the client is waiting for a
response from the server. Have a look at the gnome-packagekit code for
an example.

> Conclusion: I hadn't any "good" reason for running all in threads, except
> for the whish to avoid the UI freeze. Unfortunately this did not solve the
> problem but therefore the app now sometimes crashes cause I use dbus-glib
> too which is - as you said - not threadsafe. I reverted the experimental
> changes and wanted to know now if it makes sense to continue searching in
> this direction.

I think it would be a good idea to try to identify the original
freeze. If you could point to the code I can certainly have a look.

>  - 1 have an unknown role (GetTid then nothing?)

See this page for details on how it works:
http://www.packagekit.org/gtk-doc/introduction-ideas-transactions.html

> Could you please explain those lines? Why is the daemon not processing my
> request or throwing an error message?

It's likely the thread has blocked and is not processing further
methods to the daemon. This may be a threading bug in dbus-glib, or it
may be a thread issue with your code.

Richard.