qmutex_win.cpp

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#include <qt_windows.h>

#include "qmutex.h"
#include <qatomic.h>
#include "qmutex_p.h"

QT_BEGIN_NAMESPACE

QMutexPrivate::QMutexPrivate(QMutex::RecursionMode mode)
    : QMutexData(mode), maximumSpinTime(MaximumSpinTimeThreshold), averageWaitTime(0), owner(0), count(0)
{
    event = CreateEvent(0, FALSE, FALSE, 0);
    if (!event)
        qWarning("QMutexPrivate::QMutexPrivate: Cannot create event");
}

QMutexPrivate::~QMutexPrivate()
{ CloseHandle(event); }

bool QMutexPrivate::wait(int timeout)
{
    if (contenders.fetchAndAddAcquire(1) == 0) {
        // lock acquired without waiting
        return true;
    }
    bool returnValue = (WaitForSingleObject(event, timeout < 0 ? INFINITE : timeout) ==  WAIT_OBJECT_0);
    contenders.deref();
    return returnValue;
}

void QMutexPrivate::wakeUp()
{ SetEvent(event); }

QT_END_NAMESPACE