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****************************************************************************/

#ifndef QVARIANT_P_H

#define QVARIANT_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.

//

// takes a type, returns the internal void* pointer cast

// to a pointer of the input type

#include <QtCore/qglobal.h>

#include <QtCore/qvariant.h>

QT_BEGIN_NAMESPACE

#ifdef Q_CC_SUN // Sun CC picks the wrong overload, so introduce awful hack

template <typename T>

inline T *v_cast(const QVariant::Private *nd, T * = 0)

{

    QVariant::Private *d = const_cast<QVariant::Private *>(nd);

    return ((sizeof(T) > sizeof(QVariant::Private::Data))

            ? static_cast<T *>(d->data.shared->ptr)

            : static_cast<T *>(static_cast<void *>(&d->data.c)));

}

#else // every other compiler in this world

template <typename T>

inline const T *v_cast(const QVariant::Private *d, T * = 0)

{

    return ((sizeof(T) > sizeof(QVariant::Private::Data))

            ? static_cast<const T *>(d->data.shared->ptr)

            : static_cast<const T *>(static_cast<const void *>(&d->data.c)));

}

template <typename T>

inline T *v_cast(QVariant::Private *d, T * = 0)

{

    return ((sizeof(T) > sizeof(QVariant::Private::Data))

            ? static_cast<T *>(d->data.shared->ptr)

            : static_cast<T *>(static_cast<void *>(&d->data.c)));

}

#endif

//a simple template that avoids to allocate 2 memory chunks when creating a QVariant

template <class T> class QVariantPrivateSharedEx : public QVariant::PrivateShared

{

public:

    QVariantPrivateSharedEx() : QVariant::PrivateShared(&m_t) { }

    QVariantPrivateSharedEx(const T&t) : QVariant::PrivateShared(&m_t), m_t(t) { }

private:

    T m_t;

};

// constructs a new variant if copy is 0, otherwise copy-constructs

template <class T>

inline void v_construct(QVariant::Private *x, const void *copy, T * = 0)

{

    if (sizeof(T) > sizeof(QVariant::Private::Data)) {

        x->data.shared = copy ? new QVariantPrivateSharedEx<T>(*static_cast<const T *>(copy))

                              : new QVariantPrivateSharedEx<T>;

        x->is_shared = true;

    } else {

        if (copy)

            new (&x->data.ptr) T(*static_cast<const T *>(copy));

        else

            new (&x->data.ptr) T;

    }

}

template <class T>

inline void v_construct(QVariant::Private *x, const T &t)

{

    if (sizeof(T) > sizeof(QVariant::Private::Data)) {

        x->data.shared = new QVariantPrivateSharedEx<T>(t);

        x->is_shared = true;

    } else {

        new (&x->data.ptr) T(t);

    }

}

// deletes the internal structures

template <class T>

inline void v_clear(QVariant::Private *d, T* = 0)

{

    if (sizeof(T) > sizeof(QVariant::Private::Data)) {

        //now we need to cast

        //because QVariant::PrivateShared doesn't have a virtual destructor

        delete static_cast<QVariantPrivateSharedEx<T>*>(d->data.shared);

    } else {

        v_cast<T>(d)->~T();

    }

}

Q_CORE_EXPORT const QVariant::Handler *qcoreVariantHandler();

QT_END_NAMESPACE

#endif // QVARIANT_P_H