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diff --git a/src/svnqt/smart_pointer.hpp b/src/svnqt/smart_pointer.hpp
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+/***************************************************************************
+ *   Copyright (C) 2006-2007 by Rajko Albrecht                             *
+ *   ral@alwins-world.de                                                   *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.         *
+ ***************************************************************************/
+#ifndef _smart_pointer_hpp
+#define _smart_pointer_hpp
+
+#if defined  QT_THREAD_SUPPORT
+#include "qmutex.h"
+#endif
+
+#include "svnqt/svnqt_defines.hpp"
+
+/*!
+ * \file smart_pointer.h
+ * \brief smart pointer and reference counter
+ * \author Rajko Albrecht
+ *
+ */
+
+namespace svn
+{
+
+//! simple reference counter class
+class ref_count {
+protected:
+    //! reference count member
+    long m_RefCount;
+#ifdef QT_THREAD_SUPPORT
+    QMutex m_RefcountMutex;
+#endif
+public:
+    //! first reference must be added after "new" via Pointer()
+    ref_count() : m_RefCount(0)
+#ifdef QT_THREAD_SUPPORT
+                  ,m_RefcountMutex()
+#endif
+    {}
+    virtual ~ref_count() {}
+    //! add a reference
+    void Incr() {
+#ifdef QT_THREAD_SUPPORT
+        QMutexLocker a(&m_RefcountMutex);
+#endif
+        ++m_RefCount;
+    }
+    //! delete a reference
+    bool Decr() {
+#ifdef QT_THREAD_SUPPORT
+        QMutexLocker a(&m_RefcountMutex);
+#endif
+        --m_RefCount;
+        return Shared();
+    }
+    //! is it referenced
+    bool Shared() { return (m_RefCount > 0); }
+};
+
+//! reference counting wrapper class
+template<class T> class smart_pointer {
+    //! pointer to object
+    /*!
+     * this object must contain Incr(), Decr() and Shared()
+     * methode as public members. The best way is, that it will be a child
+     * class of RefCount
+     */
+    T *ptr;
+public:
+    //! standart constructor
+    smart_pointer() { ptr = 0; }
+    //! standart destructor
+    /*!
+     * release the reference, if it were the last reference, destroys
+     * ptr
+     */
+    ~smart_pointer()
+    {
+        if (ptr && !ptr->Decr()) {
+            delete ptr;
+        }
+    }
+    //! construction
+    smart_pointer(T* t) { if ( (ptr = t) ) ptr->Incr(); }
+    //! Pointer copy
+    smart_pointer(const smart_pointer<T>& p)
+    { if ( (ptr = p.ptr) ) ptr->Incr(); }
+    //! pointer copy by assignment
+    smart_pointer<T>& operator= (const smart_pointer<T>& p)
+    {
+        // already same: nothing to do
+        if (ptr == p.ptr) return *this;
+        // decouple reference
+        if ( ptr && !ptr->Decr()) delete ptr;
+        // establish new reference
+        if ( (ptr = p.ptr) ) ptr->Incr();
+        return *this;
+    }
+    smart_pointer<T>& operator= (T*p)
+    {
+        if (ptr==p)return *this;
+        if (ptr && !ptr->Decr()) delete ptr;
+        if ( (ptr=p) ) ptr->Incr();
+        return *this;
+    }
+
+    //! cast to conventional pointer
+    operator T* () const { return ptr; }
+
+    //! deref: fails for 0 pointer
+    T& operator* () {return *ptr; }
+    //! deref: fails for 0 pointer
+    const T& operator* ()const {return *ptr; }
+
+    //! deref with method call
+    T* operator-> () {return ptr; }
+    //! deref with const method call
+    const T* operator-> ()const {return ptr; }
+
+    //! supports "if (pointer)"
+    operator bool () const { return (ptr != 0); }
+    //! "if (pointer)" as non const
+    operator bool () { return ptr != 0;}
+
+    //! support if (!pointer)"
+    bool operator! () const { return (ptr == 0); }
+    //! support if (!pointer)" as non const
+    bool operator! () { return (ptr == 0); }
+};
+
+} // namespace svn
+#endif