source: trunk/src/corelib/thread/qmutex.h@ 730

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#ifndef QMUTEX_H
#define QMUTEX_H

#include <QtCore/qglobal.h>
#include <new>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Core)

#ifndef QT_NO_THREAD

class QMutexPrivate;

class Q_CORE_EXPORT QMutex
{
    friend class QWaitCondition;
    friend class QWaitConditionPrivate;

public:
    enum RecursionMode { NonRecursive, Recursive };

    explicit QMutex(RecursionMode mode = NonRecursive);
    ~QMutex();

    void lock();
    bool tryLock();
    bool tryLock(int timeout);
    void unlock();

#if defined(QT3_SUPPORT)
    inline QT3_SUPPORT bool locked()
    {
        if (!tryLock())
            return true;
        unlock();
        return false;
    }
    inline QT3_SUPPORT_CONSTRUCTOR QMutex(bool recursive)
    {
        new (this) QMutex(recursive ? Recursive : NonRecursive);
    }
#endif

private:
    Q_DISABLE_COPY(QMutex)

    QMutexPrivate *d;
};

class Q_CORE_EXPORT QMutexLocker
{
public:
    inline explicit QMutexLocker(QMutex *m)
        : mtx(m)
    {
        Q_ASSERT_X((val & quintptr(1u)) == quintptr(0),
                   "QMutexLocker", "QMutex pointer is misaligned");
        relock();
    }
    inline ~QMutexLocker() { unlock(); }

    inline void unlock()
    {
        if (mtx) {
            if ((val & quintptr(1u)) == quintptr(1u)) {
                val &= ~quintptr(1u);
                mtx->unlock();
            }
        }
    }

    inline void relock()
    {
        if (mtx) {
            if ((val & quintptr(1u)) == quintptr(0u)) {
                mtx->lock();
                val |= quintptr(1u);
            }
        }
    }

#if defined(Q_CC_MSVC)
#pragma warning( push )
#pragma warning( disable : 4312 ) // ignoring the warning from /Wp64
#endif