Use signals for delivering input events

This patch changes both the Input::Session interface and the skeleton
for the server-side implementation of this interface
('input/component.h').

The Input::Session interface offers a new 'sigh' function, which can be
called be the client to register a signal handler. The signal handler
gets notified on the arrival of new input. This alleviates the need to
poll for input events at the client side.

The server-side skeleton for implementing input services underwent a
redesign to make it more modular and robust. I.e., there are no
global functions needed at the server side and the event-queue
enable/disable mechanism is implemented at a central place (in the root
component) rather than inside each driver.

Fixes #46

repos/dde_linux/src/lib/usb/input/input_component.cc

@@ -15,7 +15,7 @@
 
 #include <base/printf.h>
 #include <base/rpc_server.h>
-#include <input/component.h>
+#include <input/root.h>
 #include <os/ring_buffer.h>
 
 #include <lx_emul.h>
@@ -25,19 +25,27 @@
 using namespace Genode;
 
 
-/*********************
+/**
- ** Input component **
+ * Return singleton instance of input-session component
- *********************/
+ */
+static Input::Session_component &input_session()
+{
+	static Input::Session_component inst;
+	return inst;
+}
 
-typedef Ring_buffer<Input::Event, 512> Input_ring_buffer;
 
-static Input_ring_buffer ev_queue;
+/**
-
+ * Return singleton instance of input-root component
-namespace Input {
+ *
-
+ * On the first call (from 'start_input_service'), the 'ep' argument is
-	void event_handling(bool enable) { }
+ * specified. All subsequent calls (from 'input_callback') just return the
-	bool event_pending() { return !ev_queue.empty(); }
+ * reference to the singleton instance.
-	Event get_event()    { return ev_queue.get(); }
+ */
+static Input::Root_component &input_root(Rpc_entrypoint *ep = 0)
+{
+	static Input::Root_component root(*ep, input_session());
+	return root;
 }
 
 
@@ -58,20 +66,20 @@ static void input_callback(enum input_event_type type,
 	}
 
 	try {
-		ev_queue.add(Input::Event(t, code,
+		input_session().submit(Input::Event(t, code,
 		                                    absolute_x, absolute_y,
 		                                    relative_x, relative_y));
-	} catch (Input_ring_buffer::Overflow) {
+	} catch (Input::Event_queue::Overflow) {
 		PWRN("input ring buffer overflow");
 	}
 }
 
 
-void start_input_service(void *ep)
+void start_input_service(void *ep_ptr)
 {
-	Rpc_entrypoint *e = static_cast<Rpc_entrypoint *>(ep);
+	Rpc_entrypoint *ep = static_cast<Rpc_entrypoint *>(ep_ptr);
-	static Input::Root input_root(e, env()->heap());
+
-	env()->parent()->announce(e->manage(&input_root));
+	env()->parent()->announce(ep->manage(&input_root(ep)));
 
 	genode_input_register(input_callback);
 }

repos/demo/src/server/liquid_framebuffer/services.cc

@@ -11,77 +11,30 @@
  * under the terms of the GNU General Public License version 2.
  */
 
+/* Genode include */
 #include <base/env.h>
 #include <base/semaphore.h>
 #include <base/rpc_server.h>
 #include <framebuffer_session/framebuffer_session.h>
-#include <input/component.h>
+#include <input/root.h>
 #include <nitpicker_gfx/texture_painter.h>
 #include <os/pixel_rgb565.h>
+#include <os/static_root.h>
 
+/* local includes */
 #include "services.h"
 
 
 typedef Genode::Texture<Genode::Pixel_rgb565> Texture_rgb565;
 
 
-/*****************
+/**
- ** Event queue **
+ * Return singleton instance of input session component
- *****************/
-
-class Event_queue
-{
-	private:
-
-		enum { QUEUE_SIZE = 1024 };
-
-		Input::Event      _queue[QUEUE_SIZE];
-		int               _head;
-		int               _tail;
-		Genode::Semaphore _sem;
-
-	public:
-
-		/**
-		 * Constructor
  */
-		Event_queue(): _head(0), _tail(0)
+Input::Session_component &input_session()
-		{
+{
-			Scout::memset(_queue, 0, sizeof(_queue));
+	static Input::Session_component inst;
-		}
+	return inst;
-
-		void post(Input::Event ev)
-		{
-			if ((_head + 1)%QUEUE_SIZE != _tail) {
-				_queue[_head] = ev;
-				_head = (_head + 1)%QUEUE_SIZE;
-				_sem.up();
-			}
-		}
-
-		Input::Event get()
-		{
-			_sem.down();
-			Input::Event dst_ev = _queue[_tail];
-			_tail = (_tail + 1)%QUEUE_SIZE;
-			return dst_ev;
-		}
-
-		int pending() { return _head != _tail; }
-
-} _ev_queue;
-
-
-/***************************
- ** Input service backend **
- ***************************/
-
-namespace Input {
-
-	void event_handling(bool enable) { }
-	bool event_pending() { return _ev_queue.pending(); }
-	Event get_event() { return _ev_queue.get(); }
-
 }
 
 
@@ -93,16 +46,16 @@ class Window_content : public Scout::Element
 		{
 			private:
 
-				Event_queue *_ev_queue;
+				Input::Session_component &_input_session;
 				Scout::Point              _old_mouse_position;
 				Element                  *_element;
 
 			public:
 
-				Content_event_handler(Event_queue *ev_queue,
+				Content_event_handler(Input::Session_component &input_session,
 				                      Scout::Element *element)
 				:
-					_ev_queue(ev_queue), _element(element) { }
+					_input_session(input_session),_element(element) { }
 
 				void handle(Scout::Event &ev)
 				{
@@ -123,7 +76,7 @@ class Window_content : public Scout::Element
 					     : Input::Event::INVALID;
 
 					if (type != Input::Event::INVALID)
-						_ev_queue->post(Input::Event(type, code, mouse_position.x(),
+						_input_session.submit(Input::Event(type, code, mouse_position.x(),
 						                                   mouse_position.y(),
 						                                   mouse_position.x() - _old_mouse_position.x(),
 						                                   mouse_position.y() - _old_mouse_position.y()));
@@ -198,11 +151,12 @@ class Window_content : public Scout::Element
 
 	public:
 
-		Window_content(unsigned fb_w, unsigned fb_h, Event_queue *ev_queue,
+		Window_content(unsigned fb_w, unsigned fb_h,
+		               Input::Session_component &input_session,
 		               bool config_alpha)
 		:
 			_config_alpha(config_alpha),
-			_ev_handler(ev_queue, this),
+			_ev_handler(input_session, this),
 			_fb(new (Genode::env()->heap()) Fb_texture(fb_w, fb_h, _config_alpha)),
 			_next_size(fb_w, fb_h),
 			_designated_size(_next_size)
@@ -268,10 +222,10 @@ Scout::Element *window_content() { return _window_content; }
  ** Implementation of the framebuffer service **
  ***********************************************/
 
-namespace Framebuffer
+namespace Framebuffer { class Session_component; }
+
+class Framebuffer::Session_component : public Genode::Rpc_object<Session>
 {
-	class Session_component : public Genode::Rpc_object<Session>
-	{
 	private:
 
 		Window_content &_window_content;
@@ -308,36 +262,12 @@ namespace Framebuffer
 			if (_sync_sigh.valid())
 				Genode::Signal_transmitter(_sync_sigh).submit();
 		}
-	};
+};
-
-
-	class Root : public Genode::Root_component<Session_component>
-	{
-		private:
-
-			Window_content &_window_content;
-
-		protected:
-
-			Session_component *_create_session(const char *args) override {
-				return new (md_alloc()) Session_component(_window_content); }
-
-		public:
-
-			Root(Genode::Rpc_entrypoint *session_ep,
-			     Genode::Allocator      *md_alloc,
-			     Window_content         &window_content)
-			:
-				Genode::Root_component<Session_component>(session_ep, md_alloc),
-				_window_content(window_content)
-			{ }
-	};
-}
 
 
 void init_window_content(unsigned fb_w, unsigned fb_h, bool config_alpha)
 {
-	static Window_content content(fb_w, fb_h, &_ev_queue, config_alpha);
+	static Window_content content(fb_w, fb_h, input_session(), config_alpha);
 	_window_content = &content;
 }
 
@@ -346,11 +276,10 @@ void init_services(Genode::Rpc_entrypoint &ep)
 {
 	using namespace Genode;
 
-	/*
+	static Framebuffer::Session_component fb_session(*_window_content);
-	 * Let the entry point serve the framebuffer and input root interfaces
+	static Static_root<Framebuffer::Session> fb_root(ep.manage(&fb_session));
-	 */
+
-	static Framebuffer::Root    fb_root(&ep, env()->heap(), *_window_content);
+	static Input::Root_component input_root(ep, input_session());
-	static       Input::Root input_root(&ep, env()->heap());
 
 	/*
 	 * Now, the root interfaces are ready to accept requests.

repos/gems/src/server/d3m/input_service.h

@@ -110,6 +110,14 @@ namespace Input {
 			 * Flush input events
 			 */
 			Genode::size_t flush() { return _client.flush(); }
+
+			/**
+			 * Register signal handler for input notifications
+			 */
+			void sigh(Genode::Signal_context_capability sigh)
+			{
+				_client.sigh(sigh);
+			}
 	};
 
 
@@ -183,6 +191,12 @@ namespace Input {
 				}
 				return dst_count;
 			}
+
+			void sigh(Genode::Signal_context_capability sigh)
+			{
+				for (Source *e = _sources.first(); e; e = e->next())
+					e->sigh(sigh);
+			}
 	};
 
 
@@ -214,18 +228,23 @@ namespace Input {
 			 ** Input-session interface **
 			 *****************************/
 
-			Genode::Dataspace_capability dataspace() { return _ev_ds.cap(); }
+			Genode::Dataspace_capability dataspace() override { return _ev_ds.cap(); }
 
-			bool is_pending() const
+			bool is_pending() const override
 			{
 				return _source_registry.any_source_has_pending_input();
 			}
 
-			int flush()
+			int flush() override
 			{
 				return _source_registry.flush_sources(_ev_ds.local_addr<Event>(),
 				                                       MAX_EVENTS);
 			}
+
+			void sigh(Genode::Signal_context_capability sigh) override
+			{
+				_source_registry.sigh(sigh);
+			}
 	};
 
 	/**

repos/libports/src/app/qt5/qt_avplay/control_bar.cpp

@@ -17,22 +17,22 @@
 /* Qoost includes */
 #include <qoost/style.h>
 
-#include "input_service.h"
+/* local includes */
 #include "main_window.h"
 
 
 void Control_bar::_rewind()
 {
 	/* mouse click at horizontal position 0 */
-	ev_queue.add(Input::Event(Input::Event::PRESS, Input::BTN_LEFT, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::PRESS, Input::BTN_LEFT, 0, 0, 0, 0));
-	ev_queue.add(Input::Event(Input::Event::RELEASE, Input::BTN_LEFT, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::RELEASE, Input::BTN_LEFT, 0, 0, 0, 0));
 }
 
 
 void Control_bar::_pause_resume()
 {
-	ev_queue.add(Input::Event(Input::Event::PRESS, Input::KEY_SPACE, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::PRESS, Input::KEY_SPACE, 0, 0, 0, 0));
-	ev_queue.add(Input::Event(Input::Event::RELEASE, Input::KEY_SPACE, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::RELEASE, Input::KEY_SPACE, 0, 0, 0, 0));
 
 	_playing = !_playing;
 	if (_playing)
@@ -51,8 +51,9 @@ void Control_bar::_stop()
 }
 
 
-Control_bar::Control_bar()
+Control_bar::Control_bar(Input::Event_queue &event_queue)
-: _playing(true)
+:
+	_event_queue(event_queue), _playing(true)
 {
 	update_style_id(_play_pause_button, "play");
 

repos/libports/src/app/qt5/qt_avplay/control_bar.h

@@ -22,6 +22,9 @@
 #include <qoost/compound_widget.h>
 #include <qoost/qmember.h>
 
+/* Genode includes */
+#include <input/event_queue.h>
+
 struct Play_pause_button : QPushButton { Q_OBJECT };
 struct Stop_button : QPushButton { Q_OBJECT };
 struct Volume_label : QLabel { Q_OBJECT };
@@ -33,6 +36,8 @@ class Control_bar : public Compound_widget<QWidget, QHBoxLayout>
 
 	private:
 
+		Input::Event_queue &_event_queue;
+
 		QMember<Play_pause_button> _play_pause_button;
 		QMember<Stop_button>       _stop_button;
 		QMember<Volume_label>      _volume_label;
@@ -49,7 +54,7 @@ class Control_bar : public Compound_widget<QWidget, QHBoxLayout>
 
 	public:
 
-		Control_bar();
+		Control_bar(Input::Event_queue &event_queue);
 
 	Q_SIGNALS:
 

repos/libports/src/app/qt5/qt_avplay/input_service.cpp

@@ -1,40 +0,0 @@
-/*
- * \brief   Input service
- * \author  Christian Prochaska
- * \date    2012-03-29
- */
-
-/*
- * Copyright (C) 2012-2013 Genode Labs GmbH
- *
- * This file is part of the Genode OS framework, which is distributed
- * under the terms of the GNU General Public License version 2.
- */
-
-/* Genode includes */
-#include <input/component.h>
-
-#include "input_service.h"
-
-using namespace Genode;
-
-Event_queue ev_queue;
-
-
-namespace Input {
-
-	/*
-	 * Event handling is disabled on queue creation and will be enabled later if a
-	 * session is created.
-	 */
-	void event_handling(bool enable)
-	{
-		if (enable)
-			ev_queue.enable();
-		else
-			ev_queue.disable();
-	}
-
-	bool event_pending() { return !ev_queue.empty(); }
-	Event get_event() { return ev_queue.get(); }
-}

repos/libports/src/app/qt5/qt_avplay/input_service.h

@@ -1,24 +0,0 @@
-/*
- * \brief   Input service
- * \author  Christian Prochaska
- * \date    2012-03-29
- */
-
-/*
- * Copyright (C) 2012-2013 Genode Labs GmbH
- *
- * This file is part of the Genode OS framework, which is distributed
- * under the terms of the GNU General Public License version 2.
- */
-
-#ifndef _INPUT_SERVICE_H_
-#define _INPUT_SERVICE_H_
-
-/* Genode includes */
-#include <input/event_queue.h>
-
-extern Event_queue ev_queue;
-
-extern void create_input_service();
-
-#endif /* _INPUT_SERVICE_H_ */

repos/libports/src/app/qt5/qt_avplay/main.cpp

@@ -17,6 +17,11 @@
 /* qt_avplay includes */
 #include "main_window.h"
 
+/* Genode includes */
+#include <rom_session/connection.h>
+#include <base/process.h>
+#include <base/printf.h>
+
 
 static inline void load_stylesheet()
 {
@@ -37,6 +42,14 @@ int main(int argc, char *argv[])
 
 	load_stylesheet();
 
+	/* look for dynamic linker */
+	try {
+		static Genode::Rom_connection ldso_rom("ld.lib.so");
+		Genode::Process::dynamic_linker(ldso_rom.dataspace());
+	} catch (...) {
+		PERR("ld.lib.so not found");
+	}
+
 	QMember<Main_window> main_window;
 
 	main_window->show();

repos/libports/src/app/qt5/qt_avplay/main_window.cpp

@@ -11,17 +11,10 @@
  * under the terms of the GNU General Public License version 2.
  */
 
-/* Genode includes */
-#include <cap_session/connection.h>
-#include <input/component.h>
-#include <os/config.h>
-#include <rom_session/connection.h>
-
 /* qt_avplay includes */
 #include "avplay_policy.h"
 #include "filter_framebuffer_policy.h"
 #include "framebuffer_root.h"
-#include "input_service.h"
 #include "main_window.h"
 
 
@@ -42,37 +35,11 @@ struct Framebuffer_filter
 
 
 Main_window::Main_window()
+:
+	_control_bar(_input_session.event_queue())
 {
-	/* look for dynamic linker */
+	_input_registry.insert(&_input_service);
-
+	_ep.manage(&_input_root);
-	try {
-		static Rom_connection ldso_rom("ld.lib.so");
-		Process::dynamic_linker(ldso_rom.dataspace());
-	} catch (...) {
-		PERR("ld.lib.so not found");
-	}
-
-	/* get the name of the media file from the config file */
-	enum { MAX_LEN_MEDIAFILE_NAME = 256 };
-	static char mediafile[MAX_LEN_MEDIAFILE_NAME] = "mediafile";
-	try {
-		config()->xml_node().sub_node("mediafile").attribute("name").value(mediafile, sizeof(mediafile));
-	} catch(...) {
-		PWRN("no <mediafile> config node found, using \"mediafile\"");
-	}
-
-	/* create local services */
-
-	enum { STACK_SIZE = 2*sizeof(addr_t)*1024 };
-	static Cap_connection cap;
-	static Rpc_entrypoint avplay_ep(&cap, STACK_SIZE, "avplay_ep");
-	static Service_registry input_registry;
-	static Service_registry nitpicker_framebuffer_registry;
-
-	static Input::Root input_root(&avplay_ep, env()->heap());
-	static Local_service input_service(Input::Session::service_name(), &input_root);
-	input_registry.insert(&input_service);
-	avplay_ep.manage(&input_root);
 
 	/* find out which filtering framebuffer services to start and sort them in reverse order */
 
@@ -90,11 +57,11 @@ Main_window::Main_window()
 
 	/* start the filtering framebuffer services */
 
-	Service_registry *framebuffer_in_registry = &nitpicker_framebuffer_registry;
+	Service_registry *framebuffer_in_registry = &_nitpicker_framebuffer_registry;
 
 	Q_FOREACH(Framebuffer_filter *framebuffer_filter, framebuffer_filters) {
 		framebuffer_filter->framebuffer_out_registry = new Service_registry;
-		framebuffer_filter->ep = new Rpc_entrypoint(&cap, STACK_SIZE, "filter_fb_ep");
+		framebuffer_filter->ep = new Rpc_entrypoint(&_cap, STACK_SIZE, "filter_fb_ep");
 		framebuffer_filter->policy = new Filter_framebuffer_policy(framebuffer_filter->name,
 		                                                           *framebuffer_filter->ep,
 		                                                           *framebuffer_in_registry,
@@ -106,17 +73,17 @@ Main_window::Main_window()
 	}
 
 	Rpc_entrypoint *local_framebuffer_ep = framebuffer_filters.isEmpty() ?
-	                                       &avplay_ep :
+	                                       &_ep :
 	                                       framebuffer_filters.at(0)->ep;
 
 	static Framebuffer::Root framebuffer_root(local_framebuffer_ep, env()->heap(), *_avplay_widget, 640, 480);
 	static Local_service framebuffer_service(Framebuffer::Session::service_name(), &framebuffer_root);
-	nitpicker_framebuffer_registry.insert(&framebuffer_service);
+	_nitpicker_framebuffer_registry.insert(&framebuffer_service);
 
 	/* start avplay */
 
-	static Avplay_policy avplay_policy(avplay_ep, input_registry, *framebuffer_in_registry, mediafile);
+	static Avplay_policy avplay_policy(_ep, _input_registry, *framebuffer_in_registry, _mediafile_name.buf);
-	static Genode::Slave avplay_slave(avplay_ep, avplay_policy, 32*1024*1024);
+	static Genode::Slave avplay_slave(_ep, avplay_policy, 32*1024*1024);
 
 	/* add widgets to layout */
 

repos/libports/src/app/qt5/qt_avplay/main_window.h

@@ -23,6 +23,14 @@
 #include <qoost/compound_widget.h>
 #include <qoost/qmember.h>
 
+/* Genode includes */
+#include <base/service.h>
+#include <cap_session/connection.h>
+#include <input/root.h>
+#include <os/config.h>
+#include <rom_session/connection.h>
+
+/* local includes */
 #include "control_bar.h"
 
 
@@ -32,6 +40,35 @@ class Main_window : public Compound_widget<QWidget, QVBoxLayout>
 
 	private:
 
+		struct Mediafile_name
+		{
+			/* get the name of the media file from the config file */
+			enum { MAX_LEN_MEDIAFILE_NAME = 256 };
+			char buf[MAX_LEN_MEDIAFILE_NAME];
+
+			Mediafile_name()
+			{
+				Genode::strncpy(buf, "mediafile", sizeof(buf));
+				try {
+					Genode::config()->xml_node().sub_node("mediafile")
+						.attribute("name").value(buf, sizeof(buf));
+				} catch(...) {
+					PWRN("no <mediafile> config node found, using \"mediafile\"");
+				}
+			}
+		} _mediafile_name;
+
+		enum { STACK_SIZE = 2*sizeof(Genode::addr_t)*1024 };
+		Genode::Cap_connection _cap;
+		Genode::Rpc_entrypoint _ep { &_cap, STACK_SIZE, "avplay_ep" };
+		Genode::Service_registry _input_registry;
+		Genode::Service_registry _nitpicker_framebuffer_registry;
+
+		Input::Session_component _input_session;
+		Input::Root_component    _input_root { _ep, _input_session };
+
+		Genode::Local_service _input_service { Input::Session::service_name(), &_input_root };
+
 		QMember<QNitpickerViewWidget> _avplay_widget;
 		QMember<Control_bar>          _control_bar;
 

repos/libports/src/app/qt5/qt_avplay/qt_avplay.pro

@@ -6,7 +6,6 @@ HEADERS    = avplay_policy.h \
              main_window.h
 SOURCES    = control_bar.cpp \
              framebuffer_session_component.cc \
-             input_service.cpp \
              main.cpp \
              main_window.cpp
 RESOURCES  = style.qrc

repos/os/include/input/component.h

@@ -17,100 +17,61 @@
 #include <base/env.h>
 #include <base/rpc_server.h>
 #include <os/attached_ram_dataspace.h>
+#include <os/ring_buffer.h>
 #include <root/component.h>
 #include <input_session/input_session.h>
-#include <input/event.h>
+#include <input/event_queue.h>
 
 
-namespace Input {
+namespace Input { class Session_component; }
 
-	/********************
+class Input::Session_component : public Genode::Rpc_object<Input::Session>
-	 ** Input back end **
+{
-	 ********************/
-
-	/**
-	 * Enable/disable input event handling
-	 *
-	 * \param enable  enable (true) or disable (false) back end
-	 *
-	 * The front end informs the back end about when to start capturing input
-	 * events for an open session. Later, the back end may be deactivated on
-	 * session destruction.
-	 */
-	void event_handling(bool enable);
-
-	/**
-	 * Check if an event is pending
-	 */
-	bool event_pending();
-
-	/**
-	 * Wait for an event, Zzz...zz..
-	 */
-	Input::Event get_event();
-
-
-	/*****************************
-	 ** Input service front end **
-	 *****************************/
-
-	class Session_component : public Genode::Rpc_object<Session>
-	{
 	private:
 
-			/*
+		Genode::Attached_ram_dataspace _ds { Genode::env()->ram_session(),
-			 * Input event buffer that is shared with the client
+		                                     Event_queue::QUEUE_SIZE*sizeof(Input::Event) };
-			 */
-			enum { MAX_EVENTS = 1000 };
 
-			Genode::Attached_ram_dataspace _ev_ds;
+		Event_queue _event_queue;
 
 	public:
 
-			Session_component()
-			: _ev_ds(Genode::env()->ram_session(), MAX_EVENTS*sizeof(Event)) {
-				event_handling(true); }
-
-			~Session_component() {
-				event_handling(false); }
-
-			Genode::Dataspace_capability dataspace() { return _ev_ds.cap(); }
-
-			bool is_pending() const { return event_pending(); }
-
-			int flush()
-			{
-				/* dump events into event buffer dataspace */
-				int i;
-				Input::Event *ev_ds_buf = _ev_ds.local_addr<Input::Event>();
-				for (i = 0; (i < MAX_EVENTS) && event_pending(); ++i)
-					ev_ds_buf[i] = get_event();
-
-				/* return number of flushed events */
-				return i;
-			}
-	};
-
-
 		/**
-	 * Shortcut for single-client root component
+		 * Return reference to event queue of the session
 		 */
-	typedef Genode::Root_component<Session_component, Genode::Single_client> Root_component;
+		Event_queue &event_queue() { return _event_queue; }
+
+		/**
+		 * Submit input event to event queue
+		 *
+		 * \throw Input::Event_queue::Overflow
+		 */
+		void submit(Input::Event event) { _event_queue.add(event); }
 
 
-	class Root : public Root_component
+		/******************************
+		 ** Input::Session interface **
+		 ******************************/
+
+		Genode::Dataspace_capability dataspace() override { return _ds.cap(); }
+
+		bool is_pending() const override { return !_event_queue.empty(); }
+
+		int flush() override
 		{
-		protected:
+			Input::Event *dst = _ds.local_addr<Input::Event>();
 			
-			Session_component *_create_session(const char *args) {
+			unsigned cnt = 0;
-				return new (md_alloc()) Session_component(); }
+			for (; cnt < Event_queue::QUEUE_SIZE && !_event_queue.empty(); cnt++)
+				*dst++ = _event_queue.get();
 
-		public:
+			return cnt;
+		}
 
-			Root(Genode::Rpc_entrypoint *session_ep,
+		void sigh(Genode::Signal_context_capability sigh) override
-			     Genode::Allocator      *md_alloc)
+		{
-			: Root_component(session_ep, md_alloc) { }
+			_event_queue.sigh(sigh);
-	};
+		}
-}
+};
 
 #endif /* _INCLUDE__INPUT__COMPONENT_H_ */

repos/os/include/input/event_queue.h

@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (C) 2007-2013 Genode Labs GmbH
+ * Copyright (C) 2007-2014 Genode Labs GmbH
  *
  * This file is part of the Genode OS framework, which is distributed
  * under the terms of the GNU General Public License version 2.
@@ -14,57 +14,70 @@
 #ifndef _EVENT_QUEUE_H_
 #define _EVENT_QUEUE_H_
 
-#include <base/printf.h>
+#include <base/signal.h>
 #include <input/event.h>
 #include <os/ring_buffer.h>
 
-/**
+namespace Input { class Event_queue; };
+
+
+class Input::Event_queue
+{
+	public:
+
+		/**
 		 * Input event queue
 		 *
- * We expect the client to fetch events circa each 10ms. The PS/2 driver queues
+		 * We expect the client to fetch events circa each 10ms. The PS/2 driver
- * up to 255 events, which should be enough. Normally, PS/2 generates not more
+		 * queues up to 255 events, which should be enough. Normally, PS/2
- * than 16Kbit/s, which would correspond to ca. 66 mouse events per 10ms.
+		 * generates not more than 16Kbit/s, which would correspond to ca. 66 mouse
+		 * events per 10ms.
 		 */
-class Event_queue
+		enum { QUEUE_SIZE = 512U };
-{
+
 	private:
 
-		bool                           _enabled;
+		Ring_buffer<Input::Event, QUEUE_SIZE> _queue;
-		Ring_buffer<Input::Event, 512> _ev_queue;
+
+		bool _enabled = false;
+
+		Genode::Signal_context_capability _sigh;
 
 	public:
 
-		Event_queue() : _enabled(false), _ev_queue() { }
+		typedef typename Ring_buffer<Input::Event, QUEUE_SIZE>::Overflow Overflow;
 
-		void enable()  { _enabled = true; }
+		void enabled(bool enabled) { _enabled = enabled; }
-		void disable() { _enabled = false; }
 
-		void add(Input::Event e)
+		bool enabled() const { return _enabled; }
+
+		void sigh(Genode::Signal_context_capability sigh) { _sigh = sigh; }
+
+		void submit_signal()
 		{
-			if (!_enabled) return;
+			if (_sigh.valid())
-
+				Genode::Signal_transmitter(_sigh).submit();
-			try {
-				_ev_queue.add(e);
-			} catch (Ring_buffer<Input::Event, 512>::Overflow) {
-				PWRN("event buffer overflow");
-			}
 		}
 
-		Input::Event get()
+		/**
+		 * \throw Overflow
+		 */
+		void add(Input::Event ev, bool submit_signal_immediately = true)
 		{
-			if (_enabled)
+			if (!_enabled)
-				return _ev_queue.get();
+				return;
-			else
+
-				return Input::Event();
+			_queue.add(ev);
+
+			if (submit_signal_immediately)
+				submit_signal();
 		}
 
-		bool empty()
+		Input::Event get() { return _queue.get(); }
-		{
+
-			if (_enabled)
+		bool empty() const { return _queue.empty(); }
-				return _ev_queue.empty();
+
-			else
+		int avail_capacity() const { return _queue.avail_capacity(); }
-				return true;
-		}
 };
 
 #endif /* _EVENT_QUEUE_H_ */

repos/os/include/input/root.h

@@ -0,0 +1,70 @@
+/*
+ * \brief  Input root component
+ * \author Norman Feske
+ * \date   2014-05-31
+ */
+
+/*
+ * Copyright (C) 2014 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INPUT__ROOT_H_
+#define _INPUT__ROOT_H_
+
+/* Genode includes */
+#include <os/static_root.h>
+#include <input/component.h>
+
+
+namespace Input { class Root_component; }
+
+/*
+ * This input root component tracks if the session has been opened. If a client
+ * is connected, the 'Event_queue::enabled' gets enabled. This is useful to
+ * omit the enqueuing of input events into the event queue before any client is
+ * interested in receiving input events. If we would not drop such early input
+ * events, the queue might overflow when input events are generated at boot
+ * times.
+ */
+class Input::Root_component : public Genode::Static_root<Input::Session>
+{
+	private:
+
+		Genode::Rpc_entrypoint   &_ep;
+		Input::Session_component &_session;
+
+	public:
+
+		Root_component(Genode::Rpc_entrypoint &ep, Input::Session_component &session)
+		:
+			Static_root<Input::Session>(ep.manage(&session)),
+			_ep(ep), _session(session)
+		{ }
+
+		~Root_component()
+		{
+			_ep.dissolve(&_session);
+		}
+
+		Genode::Capability<Genode::Session>
+		session(Genode::Root::Session_args const &args,
+    	        Genode::Affinity           const &affinity) override
+		{
+			if (_session.event_queue().enabled())
+				throw Root::Unavailable();
+
+			_session.event_queue().enabled(true);
+
+			return Static_root<Input::Session>::session(args, affinity);
+		}
+
+		void close(Genode::Capability<Session>)
+		{
+			_session.event_queue().enabled(false);
+		}
+};
+
+#endif /* _INPUT__ROOT_H_ */

repos/os/include/input_session/client.h

@@ -24,14 +24,17 @@ namespace Input {
 		explicit Session_client(Session_capability session)
 		: Genode::Rpc_client<Session>(session) { }
 
-		Genode::Dataspace_capability dataspace() {
+		Genode::Dataspace_capability dataspace() override {
 			return call<Rpc_dataspace>(); }
 
-		bool is_pending() const {
+		bool is_pending() const override {
 			return call<Rpc_is_pending>(); }
 
-		int flush() {
+		int flush() override {
 			return call<Rpc_flush>(); }
+
+		void sigh(Genode::Signal_context_capability sigh) override {
+			call<Rpc_sigh>(sigh); }
 	};
 }
 

repos/os/include/input_session/input_session.h

@@ -17,6 +17,7 @@
 #include <dataspace/capability.h>
 #include <base/rpc_server.h>
 #include <session/session.h>
+#include <base/signal.h>
 
 namespace Input {
 
@@ -45,6 +46,11 @@ namespace Input {
 		 */
 		virtual int flush() = 0;
 
+		/**
+		 * Register signal handler to be notified on arrival of new input
+		 */
+		virtual void sigh(Genode::Signal_context_capability) = 0;
+
 
 		/*********************
 		 ** RPC declaration **
@@ -53,8 +59,9 @@ namespace Input {
 		GENODE_RPC(Rpc_dataspace, Genode::Dataspace_capability, dataspace);
 		GENODE_RPC(Rpc_is_pending, bool, is_pending);
 		GENODE_RPC(Rpc_flush, int, flush);
+		GENODE_RPC(Rpc_sigh, void, sigh, Genode::Signal_context_capability);
 
-		GENODE_RPC_INTERFACE(Rpc_dataspace, Rpc_is_pending, Rpc_flush);
+		GENODE_RPC_INTERFACE(Rpc_dataspace, Rpc_is_pending, Rpc_flush, Rpc_sigh);
 	};
 }
 

repos/os/src/drivers/framebuffer/sdl/fb_sdl.cc

@@ -19,10 +19,12 @@
 #include <base/env.h>
 #include <base/sleep.h>
 #include <base/rpc_server.h>
-#include <root/component.h>
 #include <framebuffer_session/framebuffer_session.h>
 #include <cap_session/connection.h>
-#include <input/component.h>
+#include <input/root.h>
+
+/* local includes */
+#include <input.h>
 
 
 /*
@@ -44,10 +46,10 @@ static void                        *fb_ds_addr;
  ** Implementation of the framebuffer service **
  ***********************************************/
 
-namespace Framebuffer {
+namespace Framebuffer { class Session_component; }
 
-	class Session_component : public Genode::Rpc_object<Session>
+class Framebuffer::Session_component : public Genode::Rpc_object<Session>
-	{
+{
 	private:
 
 		Mode _mode;
@@ -100,29 +102,7 @@ namespace Framebuffer {
 			if (_sync_sigh.valid())
 				Genode::Signal_transmitter(_sync_sigh).submit();
 		}
-	};
+};
-
-
-	/**
-	 * Shortcut for single-client root component
-	 */
-	typedef Genode::Root_component<Session_component, Genode::Single_client> Root_component;
-
-
-	class Root : public Root_component
-	{
-		protected:
-
-			Session_component *_create_session(const char *args) override {
-				return new (md_alloc()) Session_component(); }
-
-		public:
-
-			Root(Genode::Rpc_entrypoint *session_ep,
-			     Genode::Allocator      *md_alloc)
-			: Root_component(session_ep, md_alloc) { }
-	};
-}
 
 
 /**
@@ -172,19 +152,21 @@ extern "C" int main(int, char**)
 	static Cap_connection cap;
 	static Rpc_entrypoint ep(&cap, STACK_SIZE, "fb_ep");
 
-	/*
+	static Input::Session_component input_session;
-	 * Let the entry point serve the framebuffer and input root interfaces
+	static Input::Root_component    input_root(ep, input_session);
-	 */
+
-	static Framebuffer::Root framebuffer_root(&ep, env()->heap());
+	static Framebuffer::Session_component fb_session;
-	static Input::Root       input_root(&ep, env()->heap());
+	static Static_root<Framebuffer::Session> fb_root(ep.manage(&fb_session));
 
 	/*
 	 * Now, the root interfaces are ready to accept requests.
 	 * This is the right time to tell mummy about our services.
 	 */
-	env()->parent()->announce(ep.manage(&framebuffer_root));
+	env()->parent()->announce(ep.manage(&fb_root));
 	env()->parent()->announce(ep.manage(&input_root));
 
-	sleep_forever();
+	for (;;)
+		input_session.submit(wait_for_event());
+
 	return 0;
 }

repos/os/src/drivers/framebuffer/sdl/input.cc

@@ -16,12 +16,11 @@
 
 /* Genode */
 #include <input/keycodes.h>
-
-/* Local */
-#include <input/component.h>
-
 #include <base/printf.h>
 
+/* local */
+#include <input.h>
+
 /**
  * Convert SDL keycode to Genode keycode
  */
@@ -139,14 +138,7 @@ static long convert_keycode(int sdl_keycode)
 };
 
 
-void Input::event_handling(bool enable) { }
+Input::Event wait_for_event()
-bool Input::event_pending() { return SDL_PollEvent(0); }
-
-
-/**
- * Wait for an event, Zzz...zz..
- */
-Input::Event Input::get_event()
 {
 	using namespace Input;
 

repos/os/src/drivers/framebuffer/sdl/input.h

@@ -0,0 +1,24 @@
+/*
+ * \brief  SDL input support
+ * \author Norman Feske
+ * \date   2006-08-16
+ */
+
+/*
+ * Copyright (C) 2006-2013 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INPUT_H_
+#define _INPUT_H_
+
+#include <input/event.h>
+
+/**
+ * Wait for an event, Zzz...zz..
+ */
+Input::Event wait_for_event();
+
+#endif /* _INPUT_H_ */

repos/os/src/drivers/framebuffer/sdl/target.mk

@@ -3,13 +3,4 @@ LIBS     = lx_hybrid
 REQUIRES = linux sdl
 SRC_CC   = fb_sdl.cc input.cc
 LX_LIBS  = sdl
-
+INC_DIR += $(PRG_DIR)
-#
-# Explicitly add host headers to the include-search location. Even though this
-# path happens to be added via the 'lx_hybrid' library via the 'HOST_INC_DIR'
-# variable, we want to give /usr/include preference for resolving 'SDL/*'
-# headers. Otherwise, if libSDL is prepared in 'libports', the build system
-# would pull-in the SDL headers from libports.
-#
-INC_DIR += /usr/include
-

repos/os/src/drivers/input/dummy/main.cc

@@ -15,6 +15,7 @@
 /* Genode */
 #include <base/env.h>
 #include <base/sleep.h>
+#include <base/signal.h>
 #include <base/rpc_server.h>
 #include <root/component.h>
 #include <cap_session/connection.h>
@@ -41,15 +42,17 @@ namespace Input {
 	{
 		public:
 
-			Dataspace_capability dataspace() { return ev_ds_cap; }
+			Dataspace_capability dataspace() override { return ev_ds_cap; }
 
-			bool is_pending() const { return 0; }
+			bool is_pending() const override { return 0; }
 
-			int flush()
+			int flush() override
 			{
 				/* return number of flushed events */
 				return 0;
 			}
+
+			void sigh(Genode::Signal_context_capability) override { }
 	};
 
 

repos/os/src/drivers/input/imx53/main.cc

@@ -13,41 +13,21 @@
  * under the terms of the GNU General Public License version 2.
  */
 
-/* Genode */
+/* Genode includes */
 #include <base/env.h>
 #include <base/sleep.h>
 #include <base/rpc_server.h>
-#include <root/component.h>
 #include <cap_session/connection.h>
 #include <platform_session/connection.h>
 #include <input/component.h>
+#include <input/root.h>
 #include <base/printf.h>
 
+/* local includes */
 #include <driver.h>
 
 using namespace Genode;
 
-static Event_queue ev_queue;
-
-namespace Input {
-
-	/*
-	 * Event handling is disabled on queue creation and will be enabled later if a
-	 * session is created.
-	 */
-	void event_handling(bool enable)
-	{
-		if (enable)
-			ev_queue.enable();
-		else
-			ev_queue.disable();
-	}
-
-	bool event_pending() { return !ev_queue.empty(); }
-	Event get_event() { return ev_queue.get(); }
-}
-
-
 int main(int argc, char **argv)
 {
 	/* initialize server entry point */
@@ -55,23 +35,25 @@ int main(int argc, char **argv)
 	static Cap_connection cap;
 	static Rpc_entrypoint ep(&cap, STACK_SIZE, "input_ep");
 
+	static Input::Session_component session;
+
 	Platform::Connection plat_drv;
 	switch (plat_drv.revision()) {
 	case Platform::Session::SMD:
 		plat_drv.enable(Platform::Session::I2C_2);
 		plat_drv.enable(Platform::Session::I2C_3);
 		plat_drv.enable(Platform::Session::BUTTONS);
-		Input::Tablet_driver::factory(ev_queue);
+		Input::Tablet_driver::factory(session.event_queue());
 		break;
 	default:
 		PWRN("No input driver available for this board");
 	}
 
 	/* entry point serving input root interface */
-	static Input::Root input_root(&ep, env()->heap());
+	static Input::Root_component root(ep, session);
 
 	/* tell parent about the service */
-	env()->parent()->announce(ep.manage(&input_root));
+	env()->parent()->announce(ep.manage(&root));
 
 	/* main's done - go to sleep */
 	sleep_forever();

repos/os/src/drivers/input/ps2/pl050/main.cc

@@ -11,12 +11,15 @@
  * under the terms of the GNU General Public License version 2.
  */
 
+/* Genode includes */
 #include <base/env.h>
 #include <base/printf.h>
 #include <base/sleep.h>
 #include <input/component.h>
+#include <input/root.h>
 #include <cap_session/connection.h>
 
+/* local includes */
 #include "ps2_keyboard.h"
 #include "ps2_mouse.h"
 #include "irq_handler.h"
@@ -24,26 +27,6 @@
 
 using namespace Genode;
 
-static Event_queue ev_queue;
-
-namespace Input {
-
-	/*
-	 * Event handling is disabled on queue creation and will be enabled later if a
-	 * session is created.
-	 */
-	void event_handling(bool enable)
-	{
-		if (enable)
-			ev_queue.enable();
-		else
-			ev_queue.disable();
-	}
-
-	bool event_pending() { return !ev_queue.empty(); }
-	Event get_event() { return ev_queue.get(); }
-}
-
 
 int main(int argc, char **argv)
 {
@@ -52,12 +35,6 @@ int main(int argc, char **argv)
 	Serial_interface *kbd = pl050.kbd_interface();
 	Serial_interface *aux = pl050.aux_interface();
 
-	Ps2_mouse    ps2_mouse(*aux, ev_queue);
-	Ps2_keyboard ps2_keybd(*kbd, ev_queue, true);
-
-	Irq_handler ps2_mouse_irq(PL050_MOUSE_IRQ, aux, ps2_mouse);
-	Irq_handler ps2_keybd_irq(PL050_KEYBD_IRQ, kbd, ps2_keybd);
-
 	/*
 	 * Initialize server entry point
 	 */
@@ -65,11 +42,19 @@ int main(int argc, char **argv)
 	static Cap_connection cap;
 	static Rpc_entrypoint ep(&cap, STACK_SIZE, "ps2_ep");
 
+	static Input::Session_component session;
+	static Input::Root_component root(ep, session);
+
+	Ps2_mouse    ps2_mouse(*aux, session.event_queue());
+	Ps2_keyboard ps2_keybd(*kbd, session.event_queue(), true);
+
+	Irq_handler ps2_mouse_irq(PL050_MOUSE_IRQ, aux, ps2_mouse);
+	Irq_handler ps2_keybd_irq(PL050_KEYBD_IRQ, kbd, ps2_keybd);
+
 	/*
 	 * Let the entry point serve the input root interface
 	 */
-	static Input::Root input_root(&ep, env()->heap());
+	env()->parent()->announce(ep.manage(&root));
-	env()->parent()->announce(ep.manage(&input_root));
 
 	Genode::sleep_forever();
 	return 0;

repos/os/src/drivers/input/ps2/ps2_keyboard.h

@@ -31,7 +31,7 @@ class Ps2_keyboard : public Input_driver
 		static const bool verbose_scan_codes = false;
 
 		Serial_interface   &_kbd;
-		Event_queue      &_ev_queue;
+		Input::Event_queue &_ev_queue;
 		bool                _xlate_mode;
 
 		/**
@@ -363,7 +363,7 @@ class Ps2_keyboard : public Input_driver
 		 * If 'xlate_mode' is true, we do not attempt to manually switch the
 		 * keyboard to scan code set 2 but just decode the scan-code set 1.
 		 */
-		Ps2_keyboard(Serial_interface &kbd, Event_queue &ev_queue, bool xlate_mode)
+		Ps2_keyboard(Serial_interface &kbd, Input::Event_queue &ev_queue, bool xlate_mode)
 		:
 			_kbd(kbd), _ev_queue(ev_queue), _xlate_mode(xlate_mode)
 		{

repos/os/src/drivers/input/ps2/ps2_mouse.h

@@ -72,7 +72,7 @@ class Ps2_mouse : public Input_driver
 		static const bool verbose = false;
 
 		Serial_interface   &_aux;
-		Event_queue      &_ev_queue;
+		Input::Event_queue &_ev_queue;
 
 		Type                _type;
 
@@ -149,9 +149,10 @@ class Ps2_mouse : public Input_driver
 
 	public:
 
-		Ps2_mouse(Serial_interface &aux, Event_queue &ev_queue)
+		Ps2_mouse(Serial_interface &aux, Input::Event_queue &ev_queue)
 		:
-			_aux(aux), _ev_queue(ev_queue), _type(PS2),
+			_aux(aux),
+			_ev_queue(ev_queue), _type(PS2),
 			_packet_len(PS2_PACKET_LEN), _packet_idx(0)
 		{
 			for (unsigned i = 0; i < NUM_BUTTONS; ++i)

repos/os/src/drivers/input/ps2/x86/main.cc

@@ -15,6 +15,7 @@
 #include <base/printf.h>
 #include <base/sleep.h>
 #include <input/component.h>
+#include <input/root.h>
 #include <cap_session/connection.h>
 
 #include "i8042.h"
@@ -24,26 +25,6 @@
 
 using namespace Genode;
 
-static Event_queue ev_queue;
-
-namespace Input {
-
-	/*
-	 * Event handling is disabled on queue creation and will be enabled later if a
-	 * session is created.
-	 */
-	void event_handling(bool enable)
-	{
-		if (enable)
-			ev_queue.enable();
-		else
-			ev_queue.disable();
-	}
-
-	bool event_pending() { return !ev_queue.empty(); }
-	Event get_event() { return ev_queue.get(); }
-}
-
 
 int main(int argc, char **argv)
 {
@@ -52,24 +33,23 @@ int main(int argc, char **argv)
 	Serial_interface *kbd = i8042.kbd_interface();
 	Serial_interface *aux = i8042.aux_interface();
 
-	Ps2_mouse    ps2_mouse(*aux, ev_queue);
+	/*
-	Ps2_keyboard ps2_keybd(*kbd, ev_queue, i8042.kbd_xlate());
+	 * Initialize server entry point
+	 */
+	enum { STACK_SIZE = 4096 };
+	static Cap_connection cap;
+	static Rpc_entrypoint ep(&cap, STACK_SIZE, "ps2_ep");
+
+	static Input::Session_component session;
+	static Input::Root_component root(ep, session);
+
+	Ps2_mouse    ps2_mouse(*aux, session.event_queue());
+	Ps2_keyboard ps2_keybd(*kbd, session.event_queue(), i8042.kbd_xlate());
 
 	Irq_handler ps2_mouse_irq(12, ps2_mouse);
 	Irq_handler ps2_keybd_irq( 1, ps2_keybd);
 
-	/*
+	env()->parent()->announce(ep.manage(&root));
-	 * Initialize server entry point
-	 */
-	enum { STACK_SIZE = sizeof(addr_t)*1024 };
-	static Cap_connection cap;
-	static Rpc_entrypoint ep(&cap, STACK_SIZE, "ps2_ep");
-
-	/*
-	 * Let the entry point serve the input root interface
-	 */
-	static Input::Root input_root(&ep, env()->heap());
-	env()->parent()->announce(ep.manage(&input_root));
 
 	Genode::sleep_forever();
 	return 0;

repos/os/src/server/loader/input.h

@@ -66,11 +66,11 @@ namespace Input {
 			 ** Input session interface **
 			 *****************************/
 
-			Dataspace_capability dataspace() { return _real_input.dataspace(); }
+			Dataspace_capability dataspace() override { return _real_input.dataspace(); }
 
-			bool is_pending() const { return _real_input.is_pending(); }
+			bool is_pending() const override { return _real_input.is_pending(); }
 
-			int flush()
+			int flush() override
 			{
 				/* translate mouse position to child's coordinate system */
 				Transformer::Delta delta = _transformer.delta();
@@ -97,6 +97,11 @@ namespace Input {
 
 				return num_ev;
 			}
+
+			void sigh(Signal_context_capability sigh) override
+			{
+				_real_input.sigh(sigh);
+			}
 	};
 }
 

repos/os/src/server/nit_fb/main.cc

@@ -82,11 +82,11 @@ namespace Input {
 			 ** Input session interface **
 			 *****************************/
 
-			Genode::Dataspace_capability dataspace() { return _to_input_ds; }
+			Genode::Dataspace_capability dataspace() override { return _to_input_ds; }
 
-			bool is_pending() const { return _from_input->is_pending(); }
+			bool is_pending() const override { return _from_input->is_pending(); }
 
-			int flush()
+			int flush() override
 			{
 				/* flush events at input session */
 				int num_events = _from_input->flush();
@@ -103,6 +103,11 @@ namespace Input {
 				}
 				return num_events;
 			}
+
+			void sigh(Genode::Signal_context_capability sigh) override
+			{
+				_from_input->sigh(sigh);
+			}
 	};
 }
 

repos/os/src/server/nitpicker/main.cc

@@ -257,8 +257,19 @@ class Input::Session_component : public Genode::Rpc_object<Session>
 		Event      _ev_buf[MAX_EVENTS];
 		unsigned   _num_ev = 0;
 
+		Signal_context_capability _sigh;
+
 	public:
 
+		/**
+		 * Wake up client
+		 */
+		void submit_signal()
+		{
+			if (_sigh.valid())
+				Signal_transmitter(_sigh).submit();
+		}
+
 		/**
 		 * Enqueue event into local event buffer of the input session
 		 */
@@ -269,6 +280,8 @@ class Input::Session_component : public Genode::Rpc_object<Session>
 
 			/* insert event into local event buffer */
 			_ev_buf[_num_ev++] = *ev;
+
+			submit_signal();
 		}
 
 
@@ -276,11 +289,11 @@ class Input::Session_component : public Genode::Rpc_object<Session>
 		 ** Input session interface **
 		 *****************************/
 
-		Dataspace_capability dataspace() { return _ev_ram_ds.cap(); }
+		Dataspace_capability dataspace() override { return _ev_ram_ds.cap(); }
 
-		bool is_pending() const { return _num_ev > 0; }
+		bool is_pending() const override { return _num_ev > 0; }
 
-		int flush()
+		int flush() override
 		{
 			unsigned ev_cnt;
 
@@ -292,6 +305,8 @@ class Input::Session_component : public Genode::Rpc_object<Session>
 			_num_ev = 0;
 			return ev_cnt;
 		}
+
+		void sigh(Genode::Signal_context_capability sigh) override { _sigh = sigh; }
 };
 
 

repos/qt4/src/app/qt_avplay/avplay_policy.h

@@ -54,6 +54,25 @@ class Avplay_policy : public QObject, public Genode::Slave_policy
 			arg1_node.setAttribute("value", _mediafile);
 			config_node.appendChild(arg1_node);
 
+			/*
+			 * Configure libc of avplay to direct output to LOG and to obtain
+			 * the mediafile from ROM.
+			 */
+			QDomElement libc_node = config_doc.createElement("libc");
+			libc_node.setAttribute("stdout", "/dev/log");
+			libc_node.setAttribute("stderr", "/dev/log");
+			QDomElement libc_vfs_node = config_doc.createElement("vfs");
+			QDomElement libc_vfs_dev_node = config_doc.createElement("dir");
+			libc_vfs_dev_node.setAttribute("name", "dev");
+			QDomElement libc_vfs_dev_log_node = config_doc.createElement("log");
+			libc_vfs_dev_node.appendChild(libc_vfs_dev_log_node);
+			libc_vfs_node.appendChild(libc_vfs_dev_node);
+			QDomElement libc_vfs_mediafile_node = config_doc.createElement("rom");
+			libc_vfs_mediafile_node.setAttribute("name", "mediafile");
+			libc_vfs_node.appendChild(libc_vfs_mediafile_node);
+			libc_node.appendChild(libc_vfs_node);
+			config_node.appendChild(libc_node);
+
 			QDomElement sdl_audio_volume_node = config_doc.createElement("sdl_audio_volume");
 			sdl_audio_volume_node.setAttribute("value", QString::number(_sdl_audio_volume));
 			config_node.appendChild(sdl_audio_volume_node);

repos/qt4/src/app/qt_avplay/control_bar.cpp

@@ -17,22 +17,22 @@
 /* Qoost includes */
 #include <qoost/style.h>
 
-#include "input_service.h"
+/* local includes */
 #include "main_window.h"
 
 
 void Control_bar::_rewind()
 {
 	/* mouse click at horizontal position 0 */
-	ev_queue.add(Input::Event(Input::Event::PRESS, Input::BTN_LEFT, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::PRESS, Input::BTN_LEFT, 0, 0, 0, 0));
-	ev_queue.add(Input::Event(Input::Event::RELEASE, Input::BTN_LEFT, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::RELEASE, Input::BTN_LEFT, 0, 0, 0, 0));
 }
 
 
 void Control_bar::_pause_resume()
 {
-	ev_queue.add(Input::Event(Input::Event::PRESS, Input::KEY_SPACE, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::PRESS, Input::KEY_SPACE, 0, 0, 0, 0));
-	ev_queue.add(Input::Event(Input::Event::RELEASE, Input::KEY_SPACE, 0, 0, 0, 0));
+	_event_queue.add(Input::Event(Input::Event::RELEASE, Input::KEY_SPACE, 0, 0, 0, 0));
 
 	_playing = !_playing;
 	if (_playing)
@@ -51,8 +51,9 @@ void Control_bar::_stop()
 }
 
 
-Control_bar::Control_bar()
+Control_bar::Control_bar(Input::Event_queue &event_queue)
-: _playing(true)
+:
+	_event_queue(event_queue), _playing(true)
 {
 	update_style_id(_play_pause_button, "play");
 

repos/qt4/src/app/qt_avplay/control_bar.h

@@ -21,6 +21,9 @@
 #include <qoost/compound_widget.h>
 #include <qoost/qmember.h>
 
+/* Genode includes */
+#include <input/event_queue.h>
+
 struct Play_pause_button : QPushButton { Q_OBJECT };
 struct Stop_button : QPushButton { Q_OBJECT };
 struct Volume_label : QLabel { Q_OBJECT };
@@ -32,6 +35,8 @@ class Control_bar : public Compound_widget<QWidget, QHBoxLayout>
 
 	private:
 
+		Input::Event_queue &_event_queue;
+
 		QMember<Play_pause_button> _play_pause_button;
 		QMember<Stop_button>       _stop_button;
 		QMember<Volume_label>      _volume_label;
@@ -48,7 +53,7 @@ class Control_bar : public Compound_widget<QWidget, QHBoxLayout>
 
 	public:
 
-		Control_bar();
+		Control_bar(Input::Event_queue &event_queue);
 
 	Q_SIGNALS:
 

repos/qt4/src/app/qt_avplay/input_service.cpp

@@ -1,40 +0,0 @@
-/*
- * \brief   Input service
- * \author  Christian Prochaska
- * \date    2012-03-29
- */
-
-/*
- * Copyright (C) 2012-2013 Genode Labs GmbH
- *
- * This file is part of the Genode OS framework, which is distributed
- * under the terms of the GNU General Public License version 2.
- */
-
-/* Genode includes */
-#include <input/component.h>
-
-#include "input_service.h"
-
-using namespace Genode;
-
-Event_queue ev_queue;
-
-
-namespace Input {
-
-	/*
-	 * Event handling is disabled on queue creation and will be enabled later if a
-	 * session is created.
-	 */
-	void event_handling(bool enable)
-	{
-		if (enable)
-			ev_queue.enable();
-		else
-			ev_queue.disable();
-	}
-
-	bool event_pending() { return !ev_queue.empty(); }
-	Event get_event() { return ev_queue.get(); }
-}

repos/qt4/src/app/qt_avplay/input_service.h

@@ -1,24 +0,0 @@
-/*
- * \brief   Input service
- * \author  Christian Prochaska
- * \date    2012-03-29
- */
-
-/*
- * Copyright (C) 2012-2013 Genode Labs GmbH
- *
- * This file is part of the Genode OS framework, which is distributed
- * under the terms of the GNU General Public License version 2.
- */
-
-#ifndef _INPUT_SERVICE_H_
-#define _INPUT_SERVICE_H_
-
-/* Genode includes */
-#include <input/event_queue.h>
-
-extern Event_queue ev_queue;
-
-extern void create_input_service();
-
-#endif /* _INPUT_SERVICE_H_ */

repos/qt4/src/app/qt_avplay/main.cpp

@@ -17,6 +17,11 @@
 /* qt_avplay includes */
 #include "main_window.h"
 
+/* Genode includes */
+#include <rom_session/connection.h>
+#include <base/process.h>
+#include <base/printf.h>
+
 
 static inline void load_stylesheet()
 {
@@ -37,6 +42,14 @@ int main(int argc, char *argv[])
 
 	load_stylesheet();
 
+	/* look for dynamic linker */
+	try {
+		static Genode::Rom_connection ldso_rom("ld.lib.so");
+		Genode::Process::dynamic_linker(ldso_rom.dataspace());
+	} catch (...) {
+		PERR("ld.lib.so not found");
+	}
+
 	QMember<Main_window> main_window;
 
 	main_window->show();

repos/qt4/src/app/qt_avplay/main_window.cpp

@@ -11,17 +11,10 @@
  * under the terms of the GNU General Public License version 2.
  */
 
-/* Genode includes */
-#include <cap_session/connection.h>
-#include <input/component.h>
-#include <os/config.h>
-#include <rom_session/connection.h>
-
 /* qt_avplay includes */
 #include "avplay_policy.h"
 #include "filter_framebuffer_policy.h"
 #include "framebuffer_root.h"
-#include "input_service.h"
 #include "main_window.h"
 
 
@@ -42,37 +35,11 @@ struct Framebuffer_filter
 
 
 Main_window::Main_window()
+:
+	_control_bar(_input_session.event_queue())
 {
-	/* look for dynamic linker */
+	_input_registry.insert(&_input_service);
-
+	_ep.manage(&_input_root);
-	try {
-		static Rom_connection ldso_rom("ld.lib.so");
-		Process::dynamic_linker(ldso_rom.dataspace());
-	} catch (...) {
-		PERR("ld.lib.so not found");
-	}
-
-	/* get the name of the media file from the config file */
-	enum { MAX_LEN_MEDIAFILE_NAME = 256 };
-	static char mediafile[MAX_LEN_MEDIAFILE_NAME] = "mediafile";
-	try {
-		config()->xml_node().sub_node("mediafile").attribute("name").value(mediafile, sizeof(mediafile));
-	} catch(...) {
-		PWRN("no <mediafile> config node found, using \"mediafile\"");
-	}
-
-	/* create local services */
-
-	enum { STACK_SIZE = 2*sizeof(addr_t)*1024 };
-	static Cap_connection cap;
-	static Rpc_entrypoint avplay_ep(&cap, STACK_SIZE, "avplay_ep");
-	static Service_registry input_registry;
-	static Service_registry nitpicker_framebuffer_registry;
-
-	static Input::Root input_root(&avplay_ep, env()->heap());
-	static Local_service input_service(Input::Session::service_name(), &input_root);
-	input_registry.insert(&input_service);
-	avplay_ep.manage(&input_root);
 
 	/* find out which filtering framebuffer services to start and sort them in reverse order */
 
@@ -90,11 +57,11 @@ Main_window::Main_window()
 
 	/* start the filtering framebuffer services */
 
-	Service_registry *framebuffer_in_registry = &nitpicker_framebuffer_registry;
+	Service_registry *framebuffer_in_registry = &_nitpicker_framebuffer_registry;
 
 	Q_FOREACH(Framebuffer_filter *framebuffer_filter, framebuffer_filters) {
 		framebuffer_filter->framebuffer_out_registry = new Service_registry;
-		framebuffer_filter->ep = new Rpc_entrypoint(&cap, STACK_SIZE, "filter_fb_ep");
+		framebuffer_filter->ep = new Rpc_entrypoint(&_cap, STACK_SIZE, "filter_fb_ep");
 		framebuffer_filter->policy = new Filter_framebuffer_policy(framebuffer_filter->name,
 		                                                           *framebuffer_filter->ep,
 		                                                           *framebuffer_in_registry,
@@ -106,17 +73,17 @@ Main_window::Main_window()
 	}
 
 	Rpc_entrypoint *local_framebuffer_ep = framebuffer_filters.isEmpty() ?
-	                                       &avplay_ep :
+	                                       &_ep :
 	                                       framebuffer_filters.at(0)->ep;
 
 	static Framebuffer::Root framebuffer_root(local_framebuffer_ep, env()->heap(), *_avplay_widget, 640, 480);
 	static Local_service framebuffer_service(Framebuffer::Session::service_name(), &framebuffer_root);
-	nitpicker_framebuffer_registry.insert(&framebuffer_service);
+	_nitpicker_framebuffer_registry.insert(&framebuffer_service);
 
 	/* start avplay */
 
-	static Avplay_policy avplay_policy(avplay_ep, input_registry, *framebuffer_in_registry, mediafile);
+	static Avplay_policy avplay_policy(_ep, _input_registry, *framebuffer_in_registry, _mediafile_name.buf);
-	static Genode::Slave avplay_slave(avplay_ep, avplay_policy, 32*1024*1024);
+	static Genode::Slave avplay_slave(_ep, avplay_policy, 32*1024*1024);
 
 	/* add widgets to layout */
 

repos/qt4/src/app/qt_avplay/main_window.h

@@ -23,6 +23,14 @@
 #include <qoost/compound_widget.h>
 #include <qoost/qmember.h>
 
+/* Genode includes */
+#include <base/service.h>
+#include <cap_session/connection.h>
+#include <input/root.h>
+#include <os/config.h>
+#include <rom_session/connection.h>
+
+/* local includes */
 #include "control_bar.h"
 
 
@@ -32,6 +40,35 @@ class Main_window : public Compound_widget<QWidget, QVBoxLayout>
 
 	private:
 
+		struct Mediafile_name
+		{
+			/* get the name of the media file from the config file */
+			enum { MAX_LEN_MEDIAFILE_NAME = 256 };
+			char buf[MAX_LEN_MEDIAFILE_NAME];
+
+			Mediafile_name()
+			{
+				Genode::strncpy(buf, "mediafile", sizeof(buf));
+				try {
+					Genode::config()->xml_node().sub_node("mediafile")
+						.attribute("name").value(buf, sizeof(buf));
+				} catch(...) {
+					PWRN("no <mediafile> config node found, using \"mediafile\"");
+				}
+			}
+		} _mediafile_name;
+
+		enum { STACK_SIZE = 2*sizeof(Genode::addr_t)*1024 };
+		Genode::Cap_connection _cap;
+		Genode::Rpc_entrypoint _ep { &_cap, STACK_SIZE, "avplay_ep" };
+		Genode::Service_registry _input_registry;
+		Genode::Service_registry _nitpicker_framebuffer_registry;
+
+		Input::Session_component _input_session;
+		Input::Root_component    _input_root { _ep, _input_session };
+
+		Genode::Local_service _input_service { Input::Session::service_name(), &_input_root };
+
 		QMember<QNitpickerViewWidget> _avplay_widget;
 		QMember<Control_bar>          _control_bar;
 

repos/qt4/src/app/qt_avplay/qt_avplay.pro

@@ -6,7 +6,6 @@ HEADERS    = avplay_policy.h \
              main_window.h
 SOURCES    = control_bar.cpp \
              framebuffer_session_component.cc \
-             input_service.cpp \
              main.cpp \
              main_window.cpp
 RESOURCES  = style.qrc

repos/qt4/src/app/qt_avplay/target.mk

@@ -6,4 +6,4 @@ include $(QT4_REP_DIR)/src/app/tmpl/target_defaults.inc
 
 include $(QT4_REP_DIR)/src/app/tmpl/target_final.inc
 
-LIBS += qnitpickerviewwidget
+LIBS += qnitpickerviewwidget qoost