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#ifndef QDELETEWATCHER_P_H
#define QDELETEWATCHER_P_H

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

#include <QtCore/qglobal.h>

QT_BEGIN_NAMESPACE

class QDeleteWatchable
{
public:
    inline QDeleteWatchable();
    inline ~QDeleteWatchable();
private:
    friend class QDeleteWatcher;
    bool *_w;
};

class QDeleteWatcher {
public:
    inline QDeleteWatcher(QDeleteWatchable *data);
    inline ~QDeleteWatcher();
    inline bool wasDeleted() const;
private:
    void *operator new(size_t);
    bool *_w;
    bool _s;
    QDeleteWatchable *m_d;
};

QDeleteWatchable::QDeleteWatchable()
: _w(0)
{
}

QDeleteWatchable::~QDeleteWatchable()
{
    if (_w) *_w = true;
}

QDeleteWatcher::QDeleteWatcher(QDeleteWatchable *data)
: _s(false), m_d(data)
{
    if (!m_d->_w)
        m_d->_w = &_s;
    _w = m_d->_w;
}

QDeleteWatcher::~QDeleteWatcher()
{
    if (false == *_w && &_s == m_d->_w)
        m_d->_w = 0;
}

bool QDeleteWatcher::wasDeleted() const
{
    return *_w;
}

QT_END_NAMESPACE

#endif // QDELETEWATCHER_P_H
