Hi,
I posted yesterday, and whilst I didn't figure out an answer the
question about the sequencing of the _put call, I did find another way
to get what I need. I wanted to get the index of a sink input after
creation, but before it plays, so that I can implement sink-input
switching and other stream manipulation (volume changes, etc.) in
response to audio policy changes, on an embedded system.
I can't explain why _put is called after the stream completes
playback, but I did discover a different way to be notified of sink-
input creation with the completely filled sink input, using
pa_subscription. Recall that neither sink-input new hook or the sink-
input fixate hook will call back with a complete sink-input (the index
of the sink-input has not been set with either) and that I was not
seeing the sink-input put hook being called until after a stream had
completed playback. So the method I came across (modified from one of
the existing module sources) is as follows.
Install a subscription routine using in the module init routine:
u->subscription = pa_subscription_new(m->core,
PA_SUBSCRIPTION_MASK_SINK_INPUT, subscribe_callback, u);
This allows us to get notifications on sink-input creations. When
this routine is called back, it will be passed the index of the
created sink input which makes getting at the actual sink-input to
inspect it's fields really easy.
Here is a subscribe callback to do this:
static void subscribe_callback(pa_core *c,
pa_subscription_event_type_t t, uint32_t idx, void *userdata) {
struct userdata *u = userdata;
pa_sink_input *si = NULL;
pa_assert(c);
pa_assert(u);
pa_log("> pa__init");
/* we are only interested in sink-input creation events */
if (t != PA_SUBSCRIPTION_EVENT_SINK_INPUT|
PA_SUBSCRIPTION_EVENT_NEW) {
pa_log("< pa__init - not a new sink input");
return;
} else {
if (!(si = pa_idxset_get_by_index(c->sink_inputs, idx))) {
pa_log("< pa__init - can't get index");
return;
}
}
pa_log("new event received on sink-input with index %d",si->index);
}
Regards
Nick
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