Adapter for connecting input and event servers

This is an intermediate helper component for the transition of input
servers into event clients. It works analogously to the
input_event_bridge but it connects servers instead of clients.
In particular, it can act as glue between a traditional input driver
that provides an input service and the event filter that provides an
event service. Thanks to this component, each driver can be migrated to
the event-client interface individually.

Issue #3827

repos/os/recipes/src/input_event_client/content.mk

@@ -0,0 +1,2 @@
+SRC_DIR = src/app/input_event_client
+include $(GENODE_DIR)/repos/base/recipes/src/content.inc

repos/os/recipes/src/input_event_client/hash

@@ -0,0 +1 @@
+2020-07-16 e6f7f44533e117edd6eb6c79d271ccacef345bb1

repos/os/recipes/src/input_event_client/used_apis

@@ -0,0 +1,4 @@
+base
+os
+event_session
+input_session

repos/os/src/app/input_event_client/main.cc

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+/*
+ * \brief  Application for connecting an input server with an event server
+ * \author Norman Feske
+ * \date   2020-07-16
+ */
+
+/*
+ * Copyright (C) 2020 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU Affero General Public License version 3.
+ */
+
+/* Genode includes */
+#include <event_session/connection.h>
+#include <input_session/connection.h>
+#include <base/component.h>
+
+namespace Input_event_client {
+	using namespace Genode;
+	struct Main;
+}
+
+
+struct Input_event_client::Main
+{
+	Env &_env;
+
+	Input::Connection _input { _env };
+	Event::Connection _event { _env };
+
+	Signal_handler<Main> _input_handler { _env.ep(), *this, &Main::_handle_input };
+
+	void _handle_input()
+	{
+		_event.with_batch([&] (Event::Session_client::Batch &batch) {
+			_input.for_each_event([&] (Input::Event const &event) {
+				batch.submit(event); }); });
+	}
+
+	Main(Env &env) : _env(env) { _input.sigh(_input_handler); }
+};
+
+
+void Component::construct(Genode::Env &env)
+{
+	static Input_event_client::Main inst(env);
+}

repos/os/src/app/input_event_client/target.mk

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+TARGET = input_event_client
+SRC_CC = main.cc
+LIBS   = base