genode/os/include/input/component.h
Norman Feske d880386091 Qualifying RPC functions as const
This patch makes use of the recently added support for const RPC
functions by turning 'Framebuffer::Session::mode()' and
'Input::Session::is_pending()' into const functions.
2012-01-27 16:54:05 +01:00

117 lines
2.5 KiB
C++

/*
* \brief Frontend of input service
* \author Norman Feske
* \date 2006-08-16
*/
/*
* Copyright (C) 2006-2012 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 _INCLUDE__INPUT__COMPONENT_H_
#define _INCLUDE__INPUT__COMPONENT_H_
#include <base/env.h>
#include <base/rpc_server.h>
#include <os/attached_ram_dataspace.h>
#include <root/component.h>
#include <input_session/input_session.h>
#include <input/event.h>
namespace Input {
/********************
** 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:
/*
* Input event buffer that is shared with the client
*/
enum { MAX_EVENTS = 1000 };
Genode::Attached_ram_dataspace _ev_ds;
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
*/
typedef Genode::Root_component<Session_component, Genode::Single_client> Root_component;
class Root : public Root_component
{
protected:
Session_component *_create_session(const char *args) {
return new (md_alloc()) Session_component(); }
public:
Root(Genode::Rpc_entrypoint *session_ep,
Genode::Allocator *md_alloc)
: Root_component(session_ep, md_alloc) { }
};
}
#endif /* _INCLUDE__INPUT__COMPONENT_H_ */