pointer.h

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// Copyright (C) 2001 Open Source Telecom Corporation.
//
// 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
//
// As a special exception to the GNU General Public License, permission is
// granted for additional uses of the text contained in its release
// of Common C++.
//
// The exception is that, if you link the Common C++ library with other
// files to produce an executable, this does not by itself cause the
// resulting executable to be covered by the GNU General Public License.
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// linking the Common C++ library code into it.
//
// This exception does not however invalidate any other reasons why
// the executable file might be covered by the GNU General Public License.
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// name Common C++.  If you copy code from other releases into a copy of
// Common C++, as the General Public License permits, the exception does
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#ifndef CCXX_MISSING_H_
#include <cc++/missing.h>
#endif

namespace ost {

template <class T>
class Pointer
{
protected:
        unsigned *ptrCount;
        T *ptrObject;

        void ptrDetach(void)
        {
                if(ptrCount && --(*ptrCount)==0) {
                        delete ptrObject;
                        delete ptrCount;
                }
                ptrObject = NULL;
                ptrCount = NULL;
        }

public:
        explicit Pointer(T* ptr = NULL) : ptrObject(ptr)
        {
                ptrCount = new unsigned;
                *ptrCount = 1;
        }

        Pointer(const Pointer<T> &ref)
        {
                ptrObject = ref.ptrObject;
                ptrCount = ref.ptrCount;
                ++(*ptrCount);
        }

        inline virtual ~Pointer()
                {ptrDetach();}


        Pointer& operator=(const Pointer<T> &ref)
        {
                if(this != &ref) {
                        ptrDetach();
                        ptrObject = ref.ptrObject;
                        ptrCount = ref.ptrCount;
                        ++(*ptrCount);
                }
                return *this;
        }

        inline T& operator*() const
                {return *ptrObject;};

        inline T* getObject() const
                {return ptrObject;};

        inline T* operator->() const
                {return ptrObject;};

        inline bool operator!() const
                {return (*ptrCount == 1);};

        inline int operator++() const
                {return ++(*ptrCount);};

        int operator--() const
        {
                if(*ptrCount == 1) {
                        delete this;
                        return 0;
                }
                return --(*ptrCount);
        }
};

}