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Diffstat (limited to 'src/corelib/tools/qshareddata.h')
-rw-r--r-- | src/corelib/tools/qshareddata.h | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/src/corelib/tools/qshareddata.h b/src/corelib/tools/qshareddata.h new file mode 100644 index 0000000..875560d --- /dev/null +++ b/src/corelib/tools/qshareddata.h @@ -0,0 +1,242 @@ +/**************************************************************************** +** +** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies). +** Contact: Qt Software Information (qt-info@nokia.com) +** +** This file is part of the QtCore module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the either Technology Preview License Agreement or the +** Beta Release License Agreement. +** +** GNU Lesser General Public License Usage +** 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 +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain +** additional rights. These rights are described in the Nokia Qt LGPL +** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this +** package. +** +** GNU General Public License Usage +** 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 +** met: http://www.gnu.org/copyleft/gpl.html. +** +** If you are unsure which license is appropriate for your use, please +** contact the sales department at qt-sales@nokia.com. +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#ifndef QSHAREDDATA_H +#define QSHAREDDATA_H + +#include <QtCore/qglobal.h> +#include <QtCore/qatomic.h> + +QT_BEGIN_HEADER + +QT_BEGIN_NAMESPACE + +QT_MODULE(Core) + +template <class T> class QSharedDataPointer; + +class Q_CORE_EXPORT QSharedData +{ +public: + mutable QAtomicInt ref; + + inline QSharedData() : ref(0) { } + inline QSharedData(const QSharedData &) : ref(0) { } + +private: + // using the assignment operator would lead to corruption in the ref-counting + QSharedData &operator=(const QSharedData &); +}; + +template <class T> class QSharedDataPointer +{ +public: + inline void detach() { if (d && d->ref != 1) detach_helper(); } + inline T &operator*() { detach(); return *d; } + inline const T &operator*() const { return *d; } + inline T *operator->() { detach(); return d; } + inline const T *operator->() const { return d; } + inline operator T *() { detach(); return d; } + inline operator const T *() const { return d; } + inline T *data() { detach(); return d; } + inline const T *data() const { return d; } + inline const T *constData() const { return d; } + + inline bool operator==(const QSharedDataPointer<T> &other) const { return d == other.d; } + inline bool operator!=(const QSharedDataPointer<T> &other) const { return d != other.d; } + + inline QSharedDataPointer() { d = 0; } + inline ~QSharedDataPointer() { if (d && !d->ref.deref()) delete d; } + + explicit QSharedDataPointer(T *data); + inline QSharedDataPointer(const QSharedDataPointer<T> &o) : d(o.d) { if (d) d->ref.ref(); } + inline QSharedDataPointer<T> & operator=(const QSharedDataPointer<T> &o) { + if (o.d != d) { + if (o.d) + o.d->ref.ref(); + if (d && !d->ref.deref()) + delete d; + d = o.d; + } + return *this; + } + inline QSharedDataPointer &operator=(T *o) { + if (o != d) { + if (o) + o->ref.ref(); + if (d && !d->ref.deref()) + delete d; + d = o; + } + return *this; + } + + inline bool operator!() const { return !d; } + +protected: + T *clone(); + +private: + void detach_helper(); + + T *d; +}; + +template <class T> class QExplicitlySharedDataPointer +{ +public: + typedef T Type; + + inline T &operator*() const { return *d; } + inline T *operator->() { return d; } + inline T *operator->() const { return d; } + inline T *data() const { return d; } + inline const T *constData() const { return d; } + + inline void detach() { if (d && d->ref != 1) detach_helper(); } + + inline void reset() + { + if(d && !d->ref.deref()) + delete d; + + d = 0; + } + + inline operator bool () const { return d != 0; } + + inline bool operator==(const QExplicitlySharedDataPointer<T> &other) const { return d == other.d; } + inline bool operator!=(const QExplicitlySharedDataPointer<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 QExplicitlySharedDataPointer() { d = 0; } + inline ~QExplicitlySharedDataPointer() { if (d && !d->ref.deref()) delete d; } + + explicit QExplicitlySharedDataPointer(T *data); + inline QExplicitlySharedDataPointer(const QExplicitlySharedDataPointer<T> &o) : d(o.d) { if (d) d->ref.ref(); } + +#ifndef QT_NO_MEMBER_TEMPLATES + template<class X> + inline QExplicitlySharedDataPointer(const QExplicitlySharedDataPointer<X> &o) : d(static_cast<T *>(o.data())) + { + if(d) + d->ref.ref(); + } +#endif + + inline QExplicitlySharedDataPointer<T> & operator=(const QExplicitlySharedDataPointer<T> &o) { + if (o.d != d) { + if (o.d) + o.d->ref.ref(); + if (d && !d->ref.deref()) + delete d; + d = o.d; + } + return *this; + } + inline QExplicitlySharedDataPointer &operator=(T *o) { + if (o != d) { + if (o) + o->ref.ref(); + if (d && !d->ref.deref()) + delete d; + d = o; + } + return *this; + } + + inline bool operator!() const { return !d; } + +protected: + T *clone(); + +private: + void detach_helper(); + + T *d; +}; + +template <class T> +Q_INLINE_TEMPLATE QSharedDataPointer<T>::QSharedDataPointer(T *adata) : d(adata) +{ if (d) d->ref.ref(); } + +template <class T> +Q_INLINE_TEMPLATE T *QSharedDataPointer<T>::clone() +{ + return new T(*d); +} + +template <class T> +Q_OUTOFLINE_TEMPLATE void QSharedDataPointer<T>::detach_helper() +{ + T *x = clone(); + x->ref.ref(); + if (!d->ref.deref()) + delete d; + d = x; +} + +template <class T> +Q_INLINE_TEMPLATE T *QExplicitlySharedDataPointer<T>::clone() +{ + return new T(*d); +} + +template <class T> +Q_OUTOFLINE_TEMPLATE void QExplicitlySharedDataPointer<T>::detach_helper() +{ + T *x = clone(); + x->ref.ref(); + if (!d->ref.deref()) + delete d; + d = x; +} + +template <class T> +Q_INLINE_TEMPLATE QExplicitlySharedDataPointer<T>::QExplicitlySharedDataPointer(T *adata) : d(adata) +{ if (d) d->ref.ref(); } + +QT_END_NAMESPACE + +QT_END_HEADER + +#endif // QSHAREDDATA_H |