mpd/src/event/TimerEvent.hxx
2017-12-20 10:45:30 +01:00

84 lines
2.1 KiB
C++

/*
* Copyright 2003-2017 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef MPD_TIMER_EVENT_HXX
#define MPD_TIMER_EVENT_HXX
#include "check.h"
#include "util/BindMethod.hxx"
#include <boost/intrusive/set_hook.hpp>
#include <chrono>
class EventLoop;
/**
* This class invokes a callback function after a certain amount of
* time. Use Schedule() to start the timer or Cancel() to cancel it.
*
* This class is not thread-safe, all methods must be called from the
* thread that runs the #EventLoop, except where explicitly documented
* as thread-safe.
*/
class TimerEvent final {
friend class EventLoop;
typedef boost::intrusive::set_member_hook<> TimerSetHook;
TimerSetHook timer_set_hook;
EventLoop &loop;
typedef BoundMethod<void()> Callback;
const Callback callback;
/**
* When is this timer due? This is only valid if IsActive()
* returns true.
*/
std::chrono::steady_clock::time_point due;
public:
TimerEvent(EventLoop &_loop, Callback _callback) noexcept
:loop(_loop), callback(_callback) {
}
~TimerEvent() noexcept {
Cancel();
}
EventLoop &GetEventLoop() noexcept {
return loop;
}
bool IsActive() const noexcept {
return timer_set_hook.is_linked();
}
void Schedule(std::chrono::steady_clock::duration d) noexcept;
void Cancel() noexcept;
private:
void Run() noexcept {
callback();
}
};
#endif /* MAIN_NOTIFY_H */