GThread usage in the panel

[Benedikt Meurer]

Benedikt Meurer wrote:
> Jasper Huijsmans wrote:
> 
>> Hey all, especially plugin writers,
>>
>> Yesterday, I committed a patch from Brian that adds thread 
>> initialization and locking to the panel.
>>
>> I had hoped that this would not affect anything that wasn't using 
>> threads, but it seems this is not the case: idle or timeout functions 
>> need to use gdk_thread_enter (); ...; gdk_thread_leave(); to make sure 
>> there is no conflict with other threads accessing gtk.
>>
>> Since there are currently no plugins using threads, this problem won't 
>> show up yet, but it will when e.g. the menu plugin starts using threads.
>>
>> If you implement this you can depend on the panel version 4.1.7.
> 
> 
> To easy the transition, I added some magic to the XFCE_PANEL_PLUGIN m4 
> macro. It now tests if the panel is threaded and if so, it defines 
> XFCE_PANEL_THREADED=1 and sets XFCE_PANEL_LOCK to gdk_threads_enter and 
> XFCE_PANEL_UNLOCK to gdk_threads_leave. If the panel isn't threaded, 
> XFCE_PANEL_THREADED won't be defined and XFCE_PANEL_(UN)LOCK will be 
> no-ops.
> 
> So, for panel plugin writers:
> 
> 1) get the latest depends.m4 from Xfce CVS (I've already updated the 
> depends.m4 files in berlios CVS, so if your plugin is hosted at the 
> xfce-goodies project, you don't need this step)
> 
> 2) Locate idle/timeout functions and place XFCE_PANEL_LOCK() at the 
> beginning of the function and XFCE_PANEL_UNLOCK() at the end of the 
> function (_before_ the return of course :-).

Francois, can you put this on the website, so new plugin writers do it 
right the first time :-).