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#ifndef QLOCK_P_H

#define QLOCK_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  This header file may

// change from version to version without notice, or even be

// removed.

//

// We mean it.

//

#include "QtCore/qstring.h"

QT_BEGIN_NAMESPACE

class QLockData;

class Q_GUI_EXPORT QLock

{

public:

    QLock(const QString &filename, char id, bool create = false);

    ~QLock();

    enum Type { Read, Write };

    bool isValid() const;

    void lock(Type type);

    void unlock();

    bool locked() const;

private:

    Type type;

    QLockData *data;

};

// Nice class for ensuring the lock is released.

// Just create one on the stack and the lock is automatically released

// when QLockHandle is destructed.

class Q_GUI_EXPORT QLockHandle

{

public:

    QLockHandle(QLock *l, QLock::Type type) : qlock(l) { qlock->lock(type); }

    ~QLockHandle() { if (locked()) qlock->unlock(); }

    void lock(QLock::Type type) { qlock->lock(type); }

    void unlock() { qlock->unlock(); }

    bool locked() const { return qlock->locked(); }

private:

    QLock *qlock;

};

QT_END_NAMESPACE

#endif // QLOCK_P_H