Spinlock.h

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/*
 * Copyright (C) 2012 by
 *   MetraLabs GmbH (MLAB), GERMANY
 * and
 *   Neuroinformatics and Cognitive Robotics Labs (NICR) at TU Ilmenau, GERMANY
 * All rights reserved.
 *
 * Contact: info@mira-project.org
 *
 * Commercial Usage:
 *   Licensees holding valid commercial licenses may use this file in
 *   accordance with the commercial license agreement provided with the
 *   software or, alternatively, in accordance with the terms contained in
 *   a written agreement between you and MLAB or NICR.
 *
 * GNU General Public License Usage:
 *   Alternatively, this file may be used under the terms of the GNU
 *   General Public License version 3.0 as published by the Free Software
 *   Foundation and appearing in the file LICENSE.GPL3 included in the
 *   packaging of this file. Please review the following information to
 *   ensure the GNU General Public License version 3.0 requirements will be
 *   met: http://www.gnu.org/copyleft/gpl.html.
 *   Alternatively you may (at your option) use any later version of the GNU
 *   General Public License if such license has been publicly approved by
 *   MLAB and NICR (or its successors, if any).
 *
 * IN NO EVENT SHALL "MLAB" OR "NICR" BE LIABLE TO ANY PARTY FOR DIRECT,
 * INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT OF
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 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
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#ifndef _MIRA_SPINLOCK_H_
#define _MIRA_SPINLOCK_H_

#ifndef Q_MOC_RUN
#include <boost/thread.hpp>
#endif
#include <thread/Atomic.h>

namespace mira {


class Spinlock
{
public:

    Spinlock() {
        atomic::write(&mLocked,0);
    }

    bool try_lock()
    {
        return atomic::cas(&mLocked,1,0)==0;
    }

    void lock()
    {
        while(!try_lock());
    }

    void sleeplock()
    {
        while(!try_lock())
            boost::this_thread::yield();
    }

    void unlock()
    {
        atomic::write(&mLocked,0);
    }

private:

    volatile uint32 mLocked;
};


} // namespace

#endif