Make a new DRAINED status.
Place the DRAINED status on an input IO when a stream is out of
buffers and draining.
All nodes that don't have HAVE_DATA on the input io need to copy
it to the output io and return the status. This makes sure the
DRAINED is forwarded and nodes return DRAINED from _process()
DRAINED on the resampler flushes out the last queued samples and then
forwards the DRAINED in the next iteration.
Emit a new drained signal from the context when a node returns
DRAINED. Use this to trigger the drained signal in the stream.
Abuse the xrun callback in the adapter to emit the drained signal until
almost all data left the resampler. This needs more work with a proper
signal and a buffer flag to signal the drain.
Always take the state of the builder to get the newly filtered
object, even in the case there is no filter.
Handle the case where we can't copy the pod in the case of
a NULL filter by reverting the state of the builder.
Rework the function a bit to make it possible to pass a NULL
result (to calculate the required size, for example)
Fixes#226
This tests exporting a PW_TYPE_INTERFACE_Endpoint and binding
a proxy for it through the registry, verifying that info and params
are propagated properly from one to the other
The info structure needs to be cached because there is no way to
request it from the implementation, unless we hack the add_listener
API to be used for making info requests or add a new method that
will be used just in the implementation (both are bad ideas).
The params are cached because
1) a client doing enum_params + sync will not work correctly, since
the sync call syncs with the server and not the implementation...
we could block the client to solve that, but then there is also #2
2) the implementation is not aware of the clients and therefore
it cannot keep track of who is subscribed and who is not, this
needs to happen in the server. Then if we only keep track of the
subscriptions in the server and keep requesting params from the
impl, there is no way to know if a param event coming from the
impl matches a call to enum_params or to subscribe or if it's
just an update that needs to be forwarded to subscribers.
