module-pulse-tunnel: don't block the main thread

Do the pulse context and stream connect async so that we don't have to
block the main thread.

Fixes #3221

src/modules/module-pulse-tunnel.c

@@ -518,42 +518,37 @@ static void module_schedule_destroy(struct impl *impl)
 	pw_loop_invoke(impl->main_loop, do_schedule_destroy, 1, NULL, 0, false, impl);
 }
 
-static void context_state_cb(pa_context *c, void *userdata)
+static int
+do_create_stream(struct spa_loop *loop,
+	bool async, uint32_t seq, const void *data, size_t size, void *user_data)
 {
-	struct impl *impl = userdata;
+	struct impl *impl = user_data;
-	bool do_destroy = false;
+	int res;
-	switch (pa_context_get_state(c)) {
+	if (impl->stream == NULL) {
-	case PA_CONTEXT_TERMINATED:
+		if ((res = create_stream(impl)) < 0) {
-	case PA_CONTEXT_FAILED:
+			pw_log_error("failed to create stream: %s", spa_strerror(res));
-		do_destroy = true;
+			do_schedule_destroy(loop, async, seq, NULL, 0, user_data);
-		SPA_FALLTHROUGH;
-	case PA_CONTEXT_READY:
-		pa_threaded_mainloop_signal(impl->pa_mainloop, 0);
-		break;
-	case PA_CONTEXT_UNCONNECTED:
-		do_destroy = true;
-		break;
-	case PA_CONTEXT_CONNECTING:
-	case PA_CONTEXT_AUTHORIZING:
-	case PA_CONTEXT_SETTING_NAME:
-		break;
 		}
-	if (do_destroy)
+	}
-		module_schedule_destroy(impl);
+	return 0;
 }
 
 static void stream_state_cb(pa_stream *s, void * userdata)
 {
 	struct impl *impl = userdata;
 	bool do_destroy = false;
-	switch (pa_stream_get_state(s)) {
+	pa_stream_state_t state = pa_stream_get_state(s);
+
+	pw_log_debug("stream state %d", state);
+
+	switch (state) {
 	case PA_STREAM_FAILED:
 	case PA_STREAM_TERMINATED:
 		do_destroy = true;
 		SPA_FALLTHROUGH;
 	case PA_STREAM_READY:
 		impl->pa_index = pa_stream_get_index(impl->pa_stream);
-		pa_threaded_mainloop_signal(impl->pa_mainloop, 0);
+		pw_loop_invoke(impl->main_loop, do_create_stream, 1, NULL, 0, false, impl);
 		break;
 	case PA_STREAM_UNCONNECTED:
 		do_destroy = true;
@@ -697,14 +692,96 @@ static void stream_overflow_cb(pa_stream *s, void *userdata)
 
 static void stream_latency_update_cb(pa_stream *s, void *userdata)
 {
-	struct impl *impl = userdata;
 	pa_usec_t usec;
 	int negative;
-
 	pa_stream_get_latency(s, &usec, &negative);
-
 	pw_log_debug("latency %ld negative %d", usec, negative);
-	pa_threaded_mainloop_signal(impl->pa_mainloop, 0);
+}
+
+static int create_pulse_stream(struct impl *impl)
+{
+	pa_sample_spec ss;
+	pa_channel_map map;
+	uint32_t latency_bytes, i, aux = 0;
+	const char *remote_node_target;
+	char stream_name[1024];
+	pa_buffer_attr bufferattr;
+	int err = PA_ERR_IO;
+
+	ss.format = (pa_sample_format_t) format_id2pa(impl->info.format);
+	ss.channels = impl->info.channels;
+	ss.rate = impl->info.rate;
+
+	map.channels = impl->info.channels;
+	for (i = 0; i < map.channels; i++)
+		map.map[i] = (pa_channel_position_t)channel_id2pa(impl->info.position[i], &aux);
+
+	snprintf(stream_name, sizeof(stream_name), _("Tunnel for %s@%s"),
+			pw_get_user_name(), pw_get_host_name());
+
+	pw_log_info("create stream %s", stream_name);
+
+	if (!(impl->pa_stream = pa_stream_new(impl->pa_context, stream_name, &ss, &map))) {
+		err = pa_context_errno(impl->pa_context);
+		goto exit;
+	}
+
+	pa_stream_set_state_callback(impl->pa_stream, stream_state_cb, impl);
+	pa_stream_set_read_callback(impl->pa_stream, stream_read_request_cb, impl);
+	pa_stream_set_write_callback(impl->pa_stream, stream_write_request_cb, impl);
+	pa_stream_set_underflow_callback(impl->pa_stream, stream_underflow_cb, impl);
+	pa_stream_set_overflow_callback(impl->pa_stream, stream_overflow_cb, impl);
+	pa_stream_set_latency_update_callback(impl->pa_stream, stream_latency_update_cb, impl);
+
+	remote_node_target = pw_properties_get(impl->props, PW_KEY_TARGET_OBJECT);
+
+	bufferattr.fragsize = (uint32_t) -1;
+	bufferattr.minreq = (uint32_t) -1;
+	bufferattr.maxlength = (uint32_t) -1;
+	bufferattr.prebuf = (uint32_t) -1;
+
+	latency_bytes = pa_usec_to_bytes(impl->latency_msec * SPA_USEC_PER_MSEC, &ss);
+
+	impl->target_latency = latency_bytes / impl->frame_size;
+
+	/* half in our buffer, half in the network + remote */
+	impl->target_buffer = latency_bytes / 2;
+
+	if (impl->mode == MODE_SOURCE) {
+		bufferattr.fragsize = latency_bytes / 2;
+
+		pa_context_subscribe(impl->pa_context,
+				PA_SUBSCRIPTION_MASK_SOURCE_OUTPUT, NULL, impl);
+
+		if ((err = pa_stream_connect_record(impl->pa_stream,
+				remote_node_target, &bufferattr,
+				PA_STREAM_DONT_MOVE |
+				PA_STREAM_INTERPOLATE_TIMING |
+				PA_STREAM_ADJUST_LATENCY |
+				PA_STREAM_AUTO_TIMING_UPDATE)) != 0)
+			err = pa_context_errno(impl->pa_context);
+	} else {
+		bufferattr.tlength = latency_bytes / 2;
+		bufferattr.minreq = bufferattr.tlength / 4;
+		bufferattr.prebuf = bufferattr.tlength;
+
+		pa_context_subscribe(impl->pa_context,
+				PA_SUBSCRIPTION_MASK_SINK_INPUT, NULL, impl);
+
+		if ((err = pa_stream_connect_playback(impl->pa_stream,
+				remote_node_target, &bufferattr,
+				PA_STREAM_DONT_MOVE |
+				PA_STREAM_INTERPOLATE_TIMING |
+				PA_STREAM_ADJUST_LATENCY |
+				PA_STREAM_AUTO_TIMING_UPDATE,
+				NULL, NULL)) != 0)
+			err = pa_context_errno(impl->pa_context);
+	}
+
+exit:
+	if (err != PA_OK)
+		pw_log_error("failed to create stream: %s", pa_strerror(err));
+	return err_to_res(err);
 }
 
 static int
@@ -779,6 +856,36 @@ static void context_subscribe_cb(pa_context *c, pa_subscription_event_type_t t,
 				idx, sink_input_info_cb, impl);
 }
 
+static void context_state_cb(pa_context *c, void *userdata)
+{
+	struct impl *impl = userdata;
+	bool do_destroy = false;
+	pa_context_state_t state = pa_context_get_state(c);
+
+	pw_log_debug("state %d", state);
+
+	switch (state) {
+	case PA_CONTEXT_TERMINATED:
+	case PA_CONTEXT_FAILED:
+		do_destroy = true;
+		SPA_FALLTHROUGH;
+	case PA_CONTEXT_READY:
+		if (impl->pa_stream == NULL)
+			if (create_pulse_stream(impl) < 0)
+				do_destroy = true;
+		break;
+	case PA_CONTEXT_UNCONNECTED:
+		do_destroy = true;
+		break;
+	case PA_CONTEXT_CONNECTING:
+	case PA_CONTEXT_AUTHORIZING:
+	case PA_CONTEXT_SETTING_NAME:
+		break;
+	}
+	if (do_destroy)
+		module_schedule_destroy(impl);
+}
+
 static pa_proplist* tunnel_new_proplist(struct impl *impl)
 {
 	pa_proplist *proplist = pa_proplist_new();
@@ -788,20 +895,15 @@ static pa_proplist* tunnel_new_proplist(struct impl *impl)
 	return proplist;
 }
 
-static int create_pulse_stream(struct impl *impl)
+static int start_pulse_connection(struct impl *impl)
 {
-	pa_sample_spec ss;
+	const char *server_address;
-	pa_channel_map map;
-	const char *server_address, *remote_node_target;
 	pa_proplist *props = NULL;
 	pa_mainloop_api *api;
-	char stream_name[1024];
+	int err = PA_ERR_IO;
-	pa_buffer_attr bufferattr;
-	int res = -EIO;
-	uint32_t latency_bytes, i, aux = 0;
 
 	if ((impl->pa_mainloop = pa_threaded_mainloop_new()) == NULL)
-		goto error;
+		goto exit;
 
 	api = pa_threaded_mainloop_get_api(impl->pa_mainloop);
 
@@ -810,15 +912,17 @@ static int create_pulse_stream(struct impl *impl)
 	pa_proplist_free(props);
 
 	if (impl->pa_context == NULL)
-		goto error;
+		goto exit;
 
 	pa_context_set_state_callback(impl->pa_context, context_state_cb, impl);
 
 	server_address = pw_properties_get(impl->props, "pulse.server.address");
 
+	pw_log_info("connecting to %s...", server_address);
+
 	if (pa_context_connect(impl->pa_context, server_address, 0, NULL) < 0) {
-		res = pa_context_errno(impl->pa_context);
+		err = pa_context_errno(impl->pa_context);
-		goto error;
+		goto exit;
 	}
 
 	pa_threaded_mainloop_lock(impl->pa_mainloop);
@@ -826,122 +930,18 @@ static int create_pulse_stream(struct impl *impl)
 	pa_context_set_subscribe_callback(impl->pa_context, context_subscribe_cb, impl);
 
 	if (pa_threaded_mainloop_start(impl->pa_mainloop) < 0)
-		goto error_unlock;
+		goto exit_unlock;
 
-	for (;;) {
+	err = PA_OK;
-		pa_context_state_t state;
-
-		state = pa_context_get_state(impl->pa_context);
-		if (state == PA_CONTEXT_READY)
-			break;
-
-		if (!PA_CONTEXT_IS_GOOD(state)) {
-			res = pa_context_errno(impl->pa_context);
-			goto error_unlock;
-		}
-		/* Wait until the context is ready */
-		pa_threaded_mainloop_wait(impl->pa_mainloop);
-	}
-
-	ss.format = (pa_sample_format_t) format_id2pa(impl->info.format);
-	ss.channels = impl->info.channels;
-	ss.rate = impl->info.rate;
-
-	map.channels = impl->info.channels;
-	for (i = 0; i < map.channels; i++)
-		map.map[i] = (pa_channel_position_t)channel_id2pa(impl->info.position[i], &aux);
-
-	snprintf(stream_name, sizeof(stream_name), _("Tunnel for %s@%s"),
-			pw_get_user_name(), pw_get_host_name());
-
-	if (!(impl->pa_stream = pa_stream_new(impl->pa_context, stream_name, &ss, &map))) {
-		res = pa_context_errno(impl->pa_context);
-		goto error_unlock;
-	}
-
-	pa_stream_set_state_callback(impl->pa_stream, stream_state_cb, impl);
-	pa_stream_set_read_callback(impl->pa_stream, stream_read_request_cb, impl);
-	pa_stream_set_write_callback(impl->pa_stream, stream_write_request_cb, impl);
-	pa_stream_set_underflow_callback(impl->pa_stream, stream_underflow_cb, impl);
-	pa_stream_set_overflow_callback(impl->pa_stream, stream_overflow_cb, impl);
-	pa_stream_set_latency_update_callback(impl->pa_stream, stream_latency_update_cb, impl);
-
-	remote_node_target = pw_properties_get(impl->props, PW_KEY_TARGET_OBJECT);
-
-	bufferattr.fragsize = (uint32_t) -1;
-	bufferattr.minreq = (uint32_t) -1;
-	bufferattr.maxlength = (uint32_t) -1;
-	bufferattr.prebuf = (uint32_t) -1;
-
-	latency_bytes = pa_usec_to_bytes(impl->latency_msec * SPA_USEC_PER_MSEC, &ss);
-
-	impl->target_latency = latency_bytes / impl->frame_size;
-
-	/* half in our buffer, half in the network + remote */
-	impl->target_buffer = latency_bytes / 2;
-
-	if (impl->mode == MODE_SOURCE) {
-		bufferattr.fragsize = latency_bytes / 2;
-
-		pa_context_subscribe(impl->pa_context,
-				PA_SUBSCRIPTION_MASK_SOURCE_OUTPUT, NULL, impl);
-
-		res = pa_stream_connect_record(impl->pa_stream,
-				remote_node_target, &bufferattr,
-				PA_STREAM_DONT_MOVE |
-				PA_STREAM_INTERPOLATE_TIMING |
-				PA_STREAM_ADJUST_LATENCY |
-				PA_STREAM_AUTO_TIMING_UPDATE);
-	} else {
-		bufferattr.tlength = latency_bytes / 2;
-		bufferattr.minreq = bufferattr.tlength / 4;
-		bufferattr.prebuf = bufferattr.tlength;
-
-		pa_context_subscribe(impl->pa_context,
-				PA_SUBSCRIPTION_MASK_SINK_INPUT, NULL, impl);
-
-		res = pa_stream_connect_playback(impl->pa_stream,
-				remote_node_target, &bufferattr,
-				PA_STREAM_DONT_MOVE |
-				PA_STREAM_INTERPOLATE_TIMING |
-				PA_STREAM_ADJUST_LATENCY |
-				PA_STREAM_AUTO_TIMING_UPDATE,
-				NULL, NULL);
-	}
-
-	if (res < 0) {
-		res = pa_context_errno(impl->pa_context);
-		goto error_unlock;
-	}
-
-	for (;;) {
-		pa_stream_state_t state;
-
-		state = pa_stream_get_state(impl->pa_stream);
-		if (state == PA_STREAM_READY)
-			break;
-
-		if (!PA_STREAM_IS_GOOD(state)) {
-			res = pa_context_errno(impl->pa_context);
-			goto error_unlock;
-		}
-
-		/* Wait until the stream is ready */
-		pa_threaded_mainloop_wait(impl->pa_mainloop);
-	}
 
+exit_unlock:
 	pa_threaded_mainloop_unlock(impl->pa_mainloop);
-
+exit:
-	return 0;
+	if (err != PA_OK)
-
+		pw_log_error("failed to connect: %s", pa_strerror(err));
-error_unlock:
+	return err_to_res(err);
-	pa_threaded_mainloop_unlock(impl->pa_mainloop);
-error:
-	pw_log_error("failed to connect: %s", pa_strerror(res));
-	return err_to_res(res);
 }
 
-
 static void core_error(void *data, uint32_t id, int seq, int res, const char *message)
 {
 	struct impl *impl = data;
@@ -1234,10 +1234,7 @@ int pipewire__module_init(struct pw_impl_module *module, const char *args)
 			&impl->core_listener,
 			&core_events, impl);
 
-	if ((res = create_pulse_stream(impl)) < 0)
+	if ((res = start_pulse_connection(impl)) < 0)
-		goto error;
-
-	if ((res = create_stream(impl)) < 0)
 		goto error;
 
 	pw_impl_module_add_listener(module, &impl->module_listener, &module_events, impl);