qmutex_p.h

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#ifndef QMUTEX_P_H
#define QMUTEX_P_H

#include "qglobal.h"

#if defined(_OS_UNIX_) || defined(_OS_MAC_)
#include <pthread.h>
#elif defined(_OS_WIN32_)
#include <windows.h>
#endif

class QAtomicInt
{
  public:
    QAtomicInt(int v=0) : m_value(v) {}
    bool testAndSet(int expectedValue,int newValue);
    int  fetchAndAdd(int valueToAdd);
    operator int () const { return m_value; }
    bool operator==(int value) const { return m_value == value; }
    bool operator!=(int value) const { return m_value != value; }
    bool operator!() const { return m_value == 0; }

  private:
    volatile int m_value;
};

class QMutexPrivate
{
public:
    QMutexPrivate();
    ~QMutexPrivate();

    void wait();
    void wakeUp();

    QAtomicInt contenders;

#if defined(_OS_UNIX_) || defined(_OS_MAC_)
    volatile bool wakeup;
    pthread_mutex_t mutex;
    pthread_cond_t cond;
#elif defined(_OS_WIN32_)
    HANDLE event;
#else
#error "unsupported platform"
#endif
};

#endif // QMUTEX_P_H