WConditionOneShot.h

//---------------------------------------------------------------------------
//
// Project: OpenWalnut ( http://www.openwalnut.org )
//
// Copyright 2009 OpenWalnut Community, BSV@Uni-Leipzig and CNCF@MPI-CBS
// For more information see http://www.openwalnut.org/copying
//
// This file is part of OpenWalnut.
//
// OpenWalnut is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// OpenWalnut 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with OpenWalnut. If not, see <http://www.gnu.org/licenses/>.
//
//---------------------------------------------------------------------------
 
#ifndef WCONDITIONONESHOT_H
#define WCONDITIONONESHOT_H
 
#include <atomic>
#include <shared_mutex>
 
#include <boost/thread.hpp>
 
#include "WCondition.h"
 
 
/**
 * Implements a WCondition, but can be fired only ONCE. This is useful if you want to have a thread waiting for a condition but
 * you can not assure that the thread already waits when you set the condition. This would cause the thread to wait endlessly
 * because it does not know that you already fired it.
 */
class WConditionOneShot: public WCondition
{
    friend class WConditionOneShot_test; //!< Access for test class.
public:
    /**
     * Default constructor.
     */
    WConditionOneShot();
 
    /**
     * Destructor.
     */
    virtual ~WConditionOneShot();
 
    /**
     * Wait for the condition. Sets the calling thread asleep.
     */
    virtual void wait() const;
 
    /**
     * Notifies all waiting threads.
     */
    virtual void notify();
 
protected:
    /**
     * Atomic bool whether this conditon has been done or not.
     */
    std::atomic< bool > m_isDone;
 
private:
};
 
#endif  // WCONDITIONONESHOT_H