diff options
Diffstat (limited to 'src/qml/qml/ftw/qqmlrefcount_p.h')
| -rw-r--r-- | src/qml/qml/ftw/qqmlrefcount_p.h | 147 |
1 files changed, 91 insertions, 56 deletions
diff --git a/src/qml/qml/ftw/qqmlrefcount_p.h b/src/qml/qml/ftw/qqmlrefcount_p.h index 1d016107e6..e7616915eb 100644 --- a/src/qml/qml/ftw/qqmlrefcount_p.h +++ b/src/qml/qml/ftw/qqmlrefcount_p.h @@ -1,41 +1,5 @@ -/**************************************************************************** -** -** Copyright (C) 2016 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtQml module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ +// 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 QQMLREFCOUNT_P_H #define QQMLREFCOUNT_P_H @@ -57,23 +21,34 @@ QT_BEGIN_NAMESPACE +template <typename T> +class QQmlRefCounted; -class Q_QML_PRIVATE_EXPORT QQmlRefCount +class QQmlRefCount { Q_DISABLE_COPY_MOVE(QQmlRefCount) public: inline QQmlRefCount(); inline void addref() const; - inline void release() const; inline int count() const; -protected: - inline virtual ~QQmlRefCount(); +private: + inline ~QQmlRefCount(); + template <typename T> friend class QQmlRefCounted; private: mutable QAtomicInt refCount; }; +template <typename T> +class QQmlRefCounted : public QQmlRefCount +{ +public: + inline void release() const; +protected: + inline ~QQmlRefCounted(); +}; + template<class T> class QQmlRefPointer { @@ -82,14 +57,16 @@ public: AddRef, Adopt }; - inline QQmlRefPointer(); - inline QQmlRefPointer(T *, Mode m = AddRef); - inline QQmlRefPointer(const QQmlRefPointer<T> &); - inline QQmlRefPointer(QQmlRefPointer<T> &&); + Q_NODISCARD_CTOR inline QQmlRefPointer() noexcept; + Q_NODISCARD_CTOR inline QQmlRefPointer(T *, Mode m = AddRef); + Q_NODISCARD_CTOR inline QQmlRefPointer(const QQmlRefPointer &); + Q_NODISCARD_CTOR inline QQmlRefPointer(QQmlRefPointer &&) noexcept; inline ~QQmlRefPointer(); + void swap(QQmlRefPointer &other) noexcept { qt_ptr_swap(o, other.o); } + inline QQmlRefPointer<T> &operator=(const QQmlRefPointer<T> &o); - inline QQmlRefPointer<T> &operator=(QQmlRefPointer<T> &&o); + inline QQmlRefPointer<T> &operator=(QQmlRefPointer<T> &&o) noexcept; inline bool isNull() const { return !o; } @@ -102,11 +79,54 @@ public: inline T* take() { T *res = o; o = nullptr; return res; } - friend bool operator==(const QQmlRefPointer &a, const QQmlRefPointer &b) { return a.o == b.o; } + friend bool operator==(const QQmlRefPointer &a, const QQmlRefPointer &b) noexcept + { + return a.o == b.o; + } + + friend bool operator!=(const QQmlRefPointer &a, const QQmlRefPointer &b) noexcept + { + return !(a == b); + } + + friend size_t qHash(const QQmlRefPointer &v, size_t seed = 0) noexcept + { + return qHash(v.o, seed); + } + + void reset(T *t = nullptr) + { + if (t == o) + return; + if (o) + o->release(); + if (t) + t->addref(); + o = t; + } + private: T *o; }; +namespace QQml { +/*! + \internal + Creates a QQmlRefPointer which takes ownership of a newly constructed T. + T must derive from QQmlRefCounted<T> (as we rely on an initial refcount of _1_). + T will be constructed by forwarding \a args to its constructor. + */ +template <typename T, typename ...Args> +QQmlRefPointer<T> makeRefPointer(Args&&... args) +{ + static_assert(std::is_base_of_v<QQmlRefCount, T>); + return QQmlRefPointer<T>(new T(std::forward<Args>(args)...), QQmlRefPointer<T>::Adopt); +} +} + +template <typename T> +Q_DECLARE_TYPEINFO_BODY(QQmlRefPointer<T>, Q_RELOCATABLE_TYPE); + QQmlRefCount::QQmlRefCount() : refCount(1) { @@ -123,11 +143,22 @@ void QQmlRefCount::addref() const refCount.ref(); } -void QQmlRefCount::release() const +template <typename T> +void QQmlRefCounted<T>::release() const { + static_assert(std::is_base_of_v<QQmlRefCounted, T>, + "QQmlRefCounted<T> must be a base of T (CRTP)"); Q_ASSERT(refCount.loadRelaxed() > 0); if (!refCount.deref()) - delete this; + delete static_cast<const T *>(this); +} + +template <typename T> +QQmlRefCounted<T>::~QQmlRefCounted() +{ + static_assert(std::is_final_v<T> || std::has_virtual_destructor_v<T>, + "T must either be marked final or have a virtual dtor, " + "lest release() runs into UB."); } int QQmlRefCount::count() const @@ -136,7 +167,7 @@ int QQmlRefCount::count() const } template<class T> -QQmlRefPointer<T>::QQmlRefPointer() +QQmlRefPointer<T>::QQmlRefPointer() noexcept : o(nullptr) { } @@ -157,7 +188,7 @@ QQmlRefPointer<T>::QQmlRefPointer(const QQmlRefPointer<T> &other) } template <class T> -QQmlRefPointer<T>::QQmlRefPointer(QQmlRefPointer<T> &&other) +QQmlRefPointer<T>::QQmlRefPointer(QQmlRefPointer<T> &&other) noexcept : o(other.take()) { } @@ -171,17 +202,21 @@ QQmlRefPointer<T>::~QQmlRefPointer() template<class T> QQmlRefPointer<T> &QQmlRefPointer<T>::operator=(const QQmlRefPointer<T> &other) { - if (other.o) other.o->addref(); - if (o) o->release(); + if (o == other.o) + return *this; + if (other.o) + other.o->addref(); + if (o) + o->release(); o = other.o; return *this; } template <class T> -QQmlRefPointer<T> &QQmlRefPointer<T>::operator=(QQmlRefPointer<T> &&other) +QQmlRefPointer<T> &QQmlRefPointer<T>::operator=(QQmlRefPointer<T> &&other) noexcept { QQmlRefPointer<T> m(std::move(other)); - qSwap(o, m.o); + swap(m); return *this; } |