/****************************************************************************
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** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2016 Olivier Goffart <ogoffart@woboq.com>
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** This file is part of the QtCore module of the Qt Toolkit.
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#ifndef QREADWRITELOCK_P_H
#define QREADWRITELOCK_P_H

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

#include <QtCore/private/qglobal_p.h>
#include <QtCore/qhash.h>
#include <QtCore/qwaitcondition.h>

QT_REQUIRE_CONFIG(thread);

QT_BEGIN_NAMESPACE

class QReadWriteLockPrivate
{
public:
    QReadWriteLockPrivate(bool isRecursive = false)
        : readerCount(0), writerCount(0), waitingReaders(0), waitingWriters(0),
        recursive(isRecursive), id(0), currentWriter(nullptr) {}

    QMutex mutex;
    QWaitCondition writerCond;
    QWaitCondition readerCond;
    int readerCount;
    int writerCount;
    int waitingReaders;
    int waitingWriters;
    const bool recursive;

    //Called with the mutex locked
    bool lockForWrite(int timeout);
    bool lockForRead(int timeout);
    void unlock();

    //memory management
    int id;
    void release();
    static QReadWriteLockPrivate *allocate();

    // Recusive mutex handling
    Qt::HANDLE currentWriter;
    QHash<Qt::HANDLE, int> currentReaders;

    // called with the mutex unlocked
    bool recursiveLockForWrite(int timeout);
    bool recursiveLockForRead(int timeout);
    void recursiveUnlock();

};

QT_END_NAMESPACE

#endif // QREADWRITELOCK_P_H
