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/*
* Copyright 2003-2020 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_EVENT_MASK_MONITOR_HXX
#define MPD_EVENT_MASK_MONITOR_HXX
#include "DeferEvent.hxx"
#include "util/BindMethod.hxx"
#include <atomic>
/**
* Manage a bit mask of events that have occurred. Every time the
* mask becomes non-zero, OnMask() is called in #EventLoop's thread.
*
* This class is thread-safe.
*/
class MaskMonitor final {
DeferEvent defer;
typedef BoundMethod<void(unsigned) noexcept> Callback;
const Callback callback;
std::atomic_uint pending_mask;
public:
MaskMonitor(EventLoop &_loop, Callback _callback) noexcept
:defer(_loop, BIND_THIS_METHOD(RunDeferred)),
callback(_callback), pending_mask(0) {}
auto &GetEventLoop() const noexcept {
return defer.GetEventLoop();
}
void Cancel() noexcept {
defer.Cancel();
}
void OrMask(unsigned new_mask) noexcept;
protected:
/* DeferEvent callback */
void RunDeferred() noexcept;
};
#endif