/****************************************************************************
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** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
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** This file is part of the Qt Script Generator project on Qt Labs.
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** accordance with the commercial license agreement provided with the
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** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3.0 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU General Public License version 3.0 requirements will be
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****************************************************************************/

#ifndef CODEMODEL_POINTER_H
#define CODEMODEL_POINTER_H

#include <QtCore/QSharedData>

// Since the atomic API changed in 4.4 we need to hack a little here
// to make it work with both 4.3 and 4.4 until that is not required

#if QT_VERSION >= 0x040400

#   include <QtCore/qatomic.h>
template <class T> class CodeModelPointer: public QAtomicPointer<T>

#else

template <class T> class CodeModelPointer

#endif // QT_VERSION >= 0x040400

{
public:
    typedef T Type;

#if QT_VERSION < 0x040400
    inline T &operator*() { return *d; }
    inline const T &operator*() const { return *d; }
    inline T *operator->() { return d; }
    inline const T *operator->() const { return d; }
    inline operator T *() { return d; }
    inline operator const T *() const { return d; }
    inline T *data() { return d; }
    inline const T *data() const { return d; }
    inline const T *constData() const { return d; }

    inline bool operator==(const CodeModelPointer<T> &other) const { return d == other.d; }
    inline bool operator!=(const CodeModelPointer<T> &other) const { return d != other.d; }
    inline bool operator==(const T *ptr) const { return d == ptr; }
    inline bool operator!=(const T *ptr) const { return d != ptr; }

    inline CodeModelPointer() { d = 0; }
    inline ~CodeModelPointer() { if (d && !d->ref.deref()) delete d; }

    explicit CodeModelPointer(T *data);
    inline CodeModelPointer(const CodeModelPointer<T> &o) : d(o.d) { if (d) d->ref.ref(); }
    inline CodeModelPointer<T> & operator=(const CodeModelPointer<T> &o) {
        if (o.d != d) {
            T *x = o.d;
            if (x) x->ref.ref();
            x = qAtomicSetPtr(&d, x);
            if (x && !x->ref.deref())
                delete x;
        }
        return *this;
    }
    inline CodeModelPointer &operator=(T *o) {
        if (o != d) {
            T *x = o;
            if (x) x->ref.ref();
            x = qAtomicSetPtr(&d, x);
            if (x && !x->ref.deref())
                delete x;
        }
        return *this;
    }

    inline bool operator!() const { return !d; }

private:
    T *d;
#else // QT_VERSION < 0x040400
    inline CodeModelPointer(T *value = 0) : QAtomicPointer<T>(value) {}

    inline CodeModelPointer &operator=(T *o) {
        QAtomicPointer<T>::operator=(o);
        return *this;
    }

    inline T *data() { return (T *) *this; }
    inline const T *data() const { return (const T *) *this; }
    inline const T *constData() const { return (const T *) *this; }
#endif
};

#if QT_VERSION < 0x040400
template <class T>
Q_INLINE_TEMPLATE CodeModelPointer<T>::CodeModelPointer(T *adata) : d(adata)
{ if (d) d->ref.ref(); }
#endif

#endif // CODEMODEL_POINTER_H