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

/*
 * \brief  Virtualized input session
 * \author Christian Prochaska
 * \author Norman Feske
 * \date   2010-09-02
 *
 * This input service implementation is used by the virtualized nitpicker
 * service to translate the input coordinate system from the coordinates
 * seen by the user of the virtualized session and the physical coordinates
 * dictated by the loader-session client.
 */

/*
 * Copyright (C) 2010-2017 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.
 */

#ifndef _INPUT_H_
#define _INPUT_H_

#include <base/rpc_server.h>
#include <input/event.h>
#include <input/keycodes.h>
#include <input_session/client.h>

namespace Input {

	using namespace Genode;

	typedef Genode::Point<> Motion_delta;

	class Session_component;
}


class Input::Session_component : public Rpc_object<Session>
{
	private:

		/*
		 * Noncopyable
		 */
		Session_component(Session_component const &);
		Session_component &operator = (Session_component const &);

		Session_client     _real_input;
		Motion_delta      &_motion_delta;
		Attached_dataspace _ev_ds;
		Event      * const _ev_buf;

		Genode::Signal_context_capability _sigh { };

	public:

		/**
		 * Constructor
		 */
		Session_component(Region_map        &rm,
		                  Session_capability real_input,
		                  Motion_delta      &motion_delta)
		:
			_real_input(rm, real_input), _motion_delta(motion_delta),
			_ev_ds(rm, _real_input.dataspace()),
			_ev_buf(_ev_ds.local_addr<Event>())
		{ }


		/*****************************
		 ** Input session interface **
		 *****************************/

		Dataspace_capability dataspace() override { return _real_input.dataspace(); }

		bool pending() const override { return _real_input.pending(); }

		int flush() override
		{
			/* translate mouse position to child's coordinate system */
			Motion_delta const delta = _motion_delta;

			int const num_ev = _real_input.flush();
			for (int i = 0; i < num_ev; i++) {

				Input::Event &ev = _ev_buf[i];

				ev.handle_absolute_motion([&] (int x, int y) {
					Point<> p = Point<>(x, y) + delta;
					ev = Input::Absolute_motion{p.x(), p.y()};
				});
			}

			return num_ev;
		}

		void sigh(Signal_context_capability sigh) override
		{
			/*
			 * Maintain local copy of signal-context capability to keep
			 * NOVA from flushing transitive delegations of the capability.
			 */
			_sigh = sigh;

			_real_input.sigh(sigh);
		}
};

#endif /* _INPUT_H_ */