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diff --git a/src/kernel/qguardedptr.cpp b/src/kernel/qguardedptr.cpp
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+/****************************************************************************
+**
+** Implementation of QGuardedPtr class
+**
+** Created : 990929
+**
+** Copyright (C) 1992-2008 Trolltech ASA.  All rights reserved.
+**
+** This file is part of the kernel module of the Qt GUI Toolkit.
+**
+** This file may be used under the terms of the GNU General
+** Public License versions 2.0 or 3.0 as published by the Free
+** Software Foundation and appearing in the files LICENSE.GPL2
+** and LICENSE.GPL3 included in the packaging of this file.
+** Alternatively you may (at your option) use any later version
+** of the GNU General Public License if such license has been
+** publicly approved by Trolltech ASA (or its successors, if any)
+** and the KDE Free Qt Foundation.
+**
+** Please review the following information to ensure GNU General
+** Public Licensing requirements will be met:
+** http://trolltech.com/products/qt/licenses/licensing/opensource/.
+** If you are unsure which license is appropriate for your use, please
+** review the following information:
+** http://trolltech.com/products/qt/licenses/licensing/licensingoverview
+** or contact the sales department at sales@trolltech.com.
+**
+** This file may be used under the terms of the Q Public License as
+** defined by Trolltech ASA and appearing in the file LICENSE.QPL
+** included in the packaging of this file.  Licensees holding valid Qt
+** Commercial licenses may use this file in accordance with the Qt
+** Commercial License Agreement provided with the Software.
+**
+** This file is provided "AS IS" with NO WARRANTY OF ANY KIND,
+** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted
+** herein.
+**
+**********************************************************************/
+
+#include "qguardedptr.h"
+
+/*!
+    \class QGuardedPtr qguardedptr.h
+    \brief The QGuardedPtr class is a template class that provides guarded pointers to QObjects.
+
+    \ingroup objectmodel
+    \mainclass
+
+    A guarded pointer, \c{QGuardedPtr<X>}, behaves like a normal C++
+    pointer \c{X*}, except that it is automatically set to 0 when
+    the referenced object is destroyed (unlike normal C++ pointers,
+    which become "dangling pointers" in such cases). \c X must be a
+    subclass of QObject.
+
+    Guarded pointers are useful whenever you need to store a pointer
+    to a QObject that is owned by someone else and therefore might be
+    destroyed while you still hold a reference to it. You can safely
+    test the pointer for validity.
+
+    Example:
+    \code
+	QGuardedPtr<QLabel> label = new QLabel( 0, "label" );
+	label->setText( "I like guarded pointers" );
+
+	delete (QLabel*) label; // simulate somebody destroying the label
+
+	if ( label)
+	    label->show();
+	else
+	    qDebug("The label has been destroyed");
+    \endcode
+
+    The program will output \c{The label has been destroyed} rather
+    than dereferencing an invalid address in \c label->show().
+
+    The functions and operators available with a QGuardedPtr are the
+    same as those available with a normal unguarded pointer, except
+    the pointer arithmetic operators (++, --, -, and +), which are
+    normally used only with arrays of objects. Use them like normal
+    pointers and you will not need to read this class documentation.
+
+    For creating guarded pointers, you can construct or assign to them
+    from an X* or from another guarded pointer of the same type. You
+    can compare them with each other using operator==() and
+    operator!=(), or test for 0 with isNull(). And you can dereference
+    them using either the \c *x or the \c x->member notation.
+
+    A guarded pointer will automatically cast to an X*, so you can
+    freely mix guarded and unguarded pointers. This means that if you
+    have a QGuardedPtr<QWidget>, you can pass it to a function that
+    requires a QWidget*. For this reason, it is of little value to
+    declare functions to take a QGuardedPtr as a parameter; just use
+    normal pointers. Use a QGuardedPtr when you are storing a pointer
+    over time.
+
+    Note again that class \e X must inherit QObject, or a compilation
+    or link error will result.
+*/
+
+/*!
+    \fn QGuardedPtr::QGuardedPtr()
+
+    Constructs a 0 guarded pointer.
+
+    \sa isNull()
+*/
+
+/*!
+    \fn QGuardedPtr::QGuardedPtr( T* p )
+
+    Constructs a guarded pointer that points to same object as \a p
+    points to.
+*/
+
+/*!
+    \fn QGuardedPtr::QGuardedPtr(const QGuardedPtr<T> &p)
+
+    Copy one guarded pointer from another. The constructed guarded
+    pointer points to the same object that \a p points to (which may
+    be 0).
+*/
+
+/*!
+    \fn QGuardedPtr::~QGuardedPtr()
+
+    Destroys the guarded pointer. Just like a normal pointer,
+    destroying a guarded pointer does \e not destroy the object being
+    pointed to.
+*/
+
+/*!
+    \fn QGuardedPtr<T>& QGuardedPtr::operator=(const QGuardedPtr<T> &p)
+
+    Assignment operator. This guarded pointer then points to the same
+    object as \a p points to.
+*/
+
+/*!
+    \overload QGuardedPtr<T> & QGuardedPtr::operator=(T* p)
+
+    Assignment operator. This guarded pointer then points to the same
+    object as \a p points to.
+*/
+
+/*!
+    \fn bool QGuardedPtr::operator==( const QGuardedPtr<T> &p ) const
+
+    Equality operator; implements traditional pointer semantics.
+    Returns TRUE if both \a p and this guarded pointer are 0, or if
+    both \a p and this pointer point to the same object; otherwise
+    returns FALSE.
+
+    \sa operator!=()
+*/
+
+/*!
+    \fn bool QGuardedPtr::operator!= ( const QGuardedPtr<T>& p ) const
+
+    Inequality operator; implements pointer semantics, the negation of
+    operator==(). Returns TRUE if \a p and this guarded pointer are
+    not pointing to the same object; otherwise returns FALSE.
+*/
+
+/*!
+    \fn bool QGuardedPtr::isNull() const
+
+    Returns \c TRUE if the referenced object has been destroyed or if
+    there is no referenced object; otherwise returns FALSE.
+*/
+
+/*!
+    \fn T* QGuardedPtr::operator->() const
+
+    Overloaded arrow operator; implements pointer semantics. Just use
+    this operator as you would with a normal C++ pointer.
+*/
+
+/*!
+    \fn T& QGuardedPtr::operator*() const
+
+    Dereference operator; implements pointer semantics. Just use this
+    operator as you would with a normal C++ pointer.
+*/
+
+/*!
+    \fn QGuardedPtr::operator T*() const
+
+    Cast operator; implements pointer semantics. Because of this
+    function you can pass a QGuardedPtr\<X\> to a function where an X*
+    is required.
+*/
+
+
+/* Internal classes */
+
+
+QGuardedPtrPrivate::QGuardedPtrPrivate( QObject* o)
+    : QObject(0, "_ptrpriv" ), obj( o )
+{
+    if ( obj )
+	connect( obj, SIGNAL( destroyed() ), this, SLOT( objectDestroyed() ) );
+}
+
+
+QGuardedPtrPrivate::~QGuardedPtrPrivate()
+{
+}
+
+void QGuardedPtrPrivate::reconnect( QObject *o )
+{
+    if ( obj == o )
+	return;
+    if ( obj )
+	disconnect( obj, SIGNAL( destroyed() ),
+		    this, SLOT( objectDestroyed() ) );
+    obj = o;
+    if ( obj )
+	connect( obj, SIGNAL( destroyed() ),
+		 this, SLOT( objectDestroyed() ) );
+}
+
+void QGuardedPtrPrivate::objectDestroyed()
+{
+    obj = 0;
+}