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2026-05-07 16:41:01 +02:00

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#ifndef QPOINTER_H
#define QPOINTER_H
#include <QtCore/qsharedpointer.h>
#include <QtCore/qtypeinfo.h>
#ifndef QT_NO_QOBJECT
QT_BEGIN_NAMESPACE
class QVariant;
template <class T>
class QPointer
{
static_assert(!std::is_pointer<T>::value, "QPointer's template type must not be a pointer type");
using QObjectType =
typename std::conditional<std::is_const<T>::value, const QObject, QObject>::type;
QWeakPointer<QObjectType> wp;
public:
QPointer() = default;
inline QPointer(T *p) : wp(p, true) { }
// compiler-generated copy/move ctor/assignment operators are fine!
// compiler-generated dtor is fine!
#ifdef Q_QDOC
// Stop qdoc from complaining about missing function
~QPointer();
#endif
inline void swap(QPointer &other) noexcept { wp.swap(other.wp); }
inline QPointer<T> &operator=(T* p)
{ wp.assign(static_cast<QObjectType*>(p)); return *this; }
inline T* data() const
{ return static_cast<T*>(wp.internalData()); }
inline T* get() const
{ return data(); }
inline T* operator->() const
{ return data(); }
inline T& operator*() const
{ return *data(); }
inline operator T*() const
{ return data(); }
inline bool isNull() const
{ return wp.isNull(); }
inline void clear()
{ wp.clear(); }
#define DECLARE_COMPARE_SET(T1, A1, T2, A2) \
friend bool operator==(T1, T2) \
{ return A1 == A2; } \
friend bool operator!=(T1, T2) \
{ return A1 != A2; }
#define DECLARE_TEMPLATE_COMPARE_SET(T1, A1, T2, A2) \
template <typename X> \
friend bool operator==(T1, T2) noexcept \
{ return A1 == A2; } \
template <typename X> \
friend bool operator!=(T1, T2) noexcept \
{ return A1 != A2; }
DECLARE_TEMPLATE_COMPARE_SET(const QPointer &p1, p1.data(), const QPointer<X> &p2, p2.data())
DECLARE_TEMPLATE_COMPARE_SET(const QPointer &p1, p1.data(), X *ptr, ptr)
DECLARE_TEMPLATE_COMPARE_SET(X *ptr, ptr, const QPointer &p2, p2.data())
DECLARE_COMPARE_SET(const QPointer &p1, p1.data(), std::nullptr_t, nullptr)
DECLARE_COMPARE_SET(std::nullptr_t, nullptr, const QPointer &p2, p2.data())
#undef DECLARE_COMPARE_SET
#undef DECLARE_TEMPLATE_COMPARE_SET
};
template <class T> Q_DECLARE_TYPEINFO_BODY(QPointer<T>, Q_RELOCATABLE_TYPE);
template<typename T>
QPointer<T>
qPointerFromVariant(const QVariant &variant)
{
const auto wp = QtSharedPointer::weakPointerFromVariant_internal(variant);
return QPointer<T>{qobject_cast<T*>(QtPrivate::EnableInternalData::internalData(wp))};
}
template <class T>
inline void swap(QPointer<T> &p1, QPointer<T> &p2) noexcept
{ p1.swap(p2); }
QT_END_NAMESPACE
#endif // QT_NO_QOBJECT
#endif // QPOINTER_H