qmutex_win32.cpp

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#include <windows.h>

#include "qmutex.h"
#include "qmutex_p.h"

QMutexPrivate::QMutexPrivate()
    : contenders(0)
{
  event = CreateEvent(0, FALSE, FALSE, 0);
  if (!event)
    qWarning("QMutexPrivate::QMutexPrivate: Cannot create event");
}

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

void QMutexPrivate::wait()
{
  WaitForSingleObject(event, INFINITE);
}

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

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

class QCriticalSection
{
  public:
    QCriticalSection()  { InitializeCriticalSection(&section); }
    ~QCriticalSection() { DeleteCriticalSection(&section); }
    void lock()         { EnterCriticalSection(&section); }
    void unlock()       { LeaveCriticalSection(&section); }

  private:
    CRITICAL_SECTION section;
};

static QCriticalSection qAtomicCriticalSection;

bool QAtomicInt::testAndSet(int expectedValue,int newValue)
{
  bool returnValue = false;
  qAtomicCriticalSection.lock();
  if (m_value == expectedValue)
  {
    m_value = newValue;
    returnValue = true;
  }
  qAtomicCriticalSection.unlock();
  return returnValue;
}

int QAtomicInt::fetchAndAdd(int valueToAdd)
{
  int returnValue;
  qAtomicCriticalSection.lock();
  returnValue = m_value;
  m_value += valueToAdd;
  qAtomicCriticalSection.unlock();
  return returnValue;
}