Initial import from the monolithic Qt.

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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 286 insertions, 0 deletions

diff --git a/src/corelib/tools/qshareddata.h b/src/corelib/tools/qshareddata.h
new file mode 100644
index 0000000000..14943734c5
--- /dev/null
+++ b/src/corelib/tools/qshareddata.h
@@ -0,0 +1,286 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (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 Technology Preview License Agreement accompanying
+** this package.
+**
+** 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 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@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:
+    typedef T Type;
+    typedef T *pointer;
+
+    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();
+            T *old = d;
+            d = o.d;
+            if (old && !old->ref.deref())
+                delete old;
+        }
+        return *this;
+    }
+    inline QSharedDataPointer &operator=(T *o) {
+        if (o != d) {
+            if (o)
+                o->ref.ref();
+            T *old = d;
+            d = o;
+            if (old && !old->ref.deref())
+                delete old;
+        }
+        return *this;
+    }
+#ifdef Q_COMPILER_RVALUE_REFS
+    QSharedDataPointer(QSharedDataPointer &&o) : d(o.d) { o.d = 0; }
+    inline QSharedDataPointer<T> &operator=(QSharedDataPointer<T> &&other)
+    { qSwap(d, other.d); return *this; }
+#endif
+
+    inline bool operator!() const { return !d; }
+
+    inline void swap(QSharedDataPointer &other)
+    { qSwap(d, other.d); }
+
+protected:
+    T *clone();
+
+private:
+    void detach_helper();
+
+    T *d;
+};
+
+template <class T> class QExplicitlySharedDataPointer
+{
+public:
+    typedef T Type;
+    typedef T *pointer;
+
+    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(); }
+
+    template<class X>
+    inline QExplicitlySharedDataPointer(const QExplicitlySharedDataPointer<X> &o) : d(static_cast<T *>(o.data()))
+    {
+        if(d)
+            d->ref.ref();
+    }
+
+    inline QExplicitlySharedDataPointer<T> & operator=(const QExplicitlySharedDataPointer<T> &o) {
+        if (o.d != d) {
+            if (o.d)
+                o.d->ref.ref();
+            T *old = d;
+            d = o.d;
+            if (old && !old->ref.deref())
+                delete old;
+        }
+        return *this;
+    }
+    inline QExplicitlySharedDataPointer &operator=(T *o) {
+        if (o != d) {
+            if (o)
+                o->ref.ref();
+            T *old = d;
+            d = o;
+            if (old && !old->ref.deref())
+                delete old;
+        }
+        return *this;
+    }
+#ifdef Q_COMPILER_RVALUE_REFS
+    inline QExplicitlySharedDataPointer(QExplicitlySharedDataPointer &&o) : d(o.d) { o.d = 0; }
+    inline QExplicitlySharedDataPointer<T> &operator=(QExplicitlySharedDataPointer<T> &&other)
+    { qSwap(d, other.d); return *this; }
+#endif
+
+    inline bool operator!() const { return !d; }
+
+    inline void swap(QExplicitlySharedDataPointer &other)
+    { qSwap(d, other.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(); }
+
+template <class T>
+Q_INLINE_TEMPLATE void qSwap(QSharedDataPointer<T> &p1, QSharedDataPointer<T> &p2)
+{ p1.swap(p2); }
+
+template <class T>
+Q_INLINE_TEMPLATE void qSwap(QExplicitlySharedDataPointer<T> &p1, QExplicitlySharedDataPointer<T> &p2)
+{ p1.swap(p2); }
+
+#ifndef QT_NO_STL
+QT_END_NAMESPACE
+namespace std {
+    template <class T>
+    Q_INLINE_TEMPLATE void swap(QT_PREPEND_NAMESPACE(QSharedDataPointer)<T> &p1, QT_PREPEND_NAMESPACE(QSharedDataPointer)<T> &p2)
+    { p1.swap(p2); }
+
+    template <class T>
+    Q_INLINE_TEMPLATE void swap(QT_PREPEND_NAMESPACE(QExplicitlySharedDataPointer)<T> &p1, QT_PREPEND_NAMESPACE(QExplicitlySharedDataPointer)<T> &p2)
+    { p1.swap(p2); }
+}
+QT_BEGIN_NAMESPACE
+#endif
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // QSHAREDDATA_H