qwslock_p.h

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#ifndef QWSLOCK_P_H
#define QWSLOCK_P_H

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

#include <qglobal.h>

#ifndef QT_NO_QWS_MULTIPROCESS

#ifdef QT_POSIX_IPC
#  include <semaphore.h>
#endif

QT_BEGIN_NAMESPACE

class QWSLock
{
public:
    enum LockType { BackingStore, Communication, RegionEvent };

    QWSLock(int lockId = -1);
    ~QWSLock();

    bool lock(LockType type, int timeout = -1);
    void unlock(LockType type);
    bool wait(LockType type, int timeout = -1);
    bool hasLock(LockType type);
    int id() const { return semId; }

private:
    bool up(unsigned short semNum);
    bool down(unsigned short semNum, int timeout);
    int getValue(unsigned short semNum) const;

    int semId;
    int lockCount[2];
#ifdef QT_POSIX_IPC
    sem_t *sems[3];
    bool owned;
#endif
};

QT_END_NAMESPACE

#endif // QT_NO_QWS_MULTIPROCESS

#endif // QWSLOCK_P_H