/****************************************************************************
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** Copyright (C) 2012 Digia Plc and/or its subsidiary(-ies).
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****************************************************************************/

#ifndef QMUTEXPOOL_P_H
#define QMUTEXPOOL_P_H

//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of QSettings. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//

#include "QtCore/qatomic.h"
#include "QtCore/qmutex.h"
#include "QtCore/qvarlengtharray.h"

#ifndef QT_NO_THREAD

QT_BEGIN_NAMESPACE

class Q_CORE_EXPORT QMutexPool
{
public:
    explicit QMutexPool(QMutex::RecursionMode recursionMode = QMutex::NonRecursive, int size = 131);
    ~QMutexPool();

    inline QMutex *get(const void *address) {
        int index = uint(quintptr(address)) % mutexes.count();
        QMutex *m = mutexes[index];
        if (m)
            return m;
        else
            return createMutex(index);
    }
    static QMutexPool *instance();
    static QMutex *globalInstanceGet(const void *address);

private:
    QMutex *createMutex(int index);
    QVarLengthArray<QAtomicPointer<QMutex>, 131> mutexes;
    QMutex::RecursionMode recursionMode;
};

extern Q_CORE_EXPORT QMutexPool *qt_global_mutexpool;

QT_END_NAMESPACE

#endif // QT_NO_THREAD

#endif // QMUTEXPOOL_P_H