'Twas brillig, and Tanu Kaskinen at 15/09/10 17:52 did gyre and gimble: > On Wed, 2010-09-15 at 15:37 +0100, Colin Guthrie wrote: >>> Most important to me is to figure out how you make the module >>> unload/load automatically as the headphone jack is plugged/unplugged. >>> Right now the module just fails to load if the master port is not the >>> one for the headphones. >> >> Ultimately you'll have to make the module listen to the >> PA_CORE_HOOK_SINK_STATE_CHANGED hook. The callback assigned to this hook >> will be called whenever a sink changes in the PA daemon (e.g. when it's >> port is changed). You can inspect the current active_port and either >> load, unload or noop as appropriate the actual sink object itself. > > This is not entirely correct. PA_CORE_HOOK_SINK_STATE_CHANGED is fired > only when the pa_sink.state variable changes, not when the active port > changes. For monitoring port changes, either implement a new hook > (PA_CORE_HOOK_SINK_PORT_CHANGED) and use it, or use the asynchronous > subscription system (see src/pulsecore/core-subscribe.h for the API). I > would prefer the first alternative - the synchronous hook callbacks are > easier to get right than the asynchronous subscription callbacks. Ahh right, thanks Tanu. Yeah I initially thought about the subscription stuff but then somehow just assumed the hook system would be sufficient, but didn't look into the details. I do wonder however if a state change would ultimately be fired when the port changes anyway... but if it does it would be too often anyway. A new hook in the core would really be needed here which makes the job a little more complex for you :( Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited [http://www.tribalogic.net/] Open Source: Mandriva Linux Contributor [http://www.mandriva.com/] PulseAudio Hacker [http://www.pulseaudio.org/] Trac Hacker [http://trac.edgewall.org/]
