Home

C-Bits Package Documentation

Project Page

---

           

---

sync_ptr.h

Go to the documentation of this file.

/* ====================================================================
 *              The CBITS Software License, Version 1.0
 *
 *               Copyright (c) 2002-2003 Bruce Lowery
 *                       All rights reserved
 *
 * Redistribution and use of this software, in source and binary forms, 
 * with or without modification, are permitted provided that the above 
 * copyright notice, this paragraph, and the following paragraph are 
 * retained in each source code file.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL BRUCE LOWERY OR OTHER CONTRIBUTORS 
 * TO THE CBITS LIBRARY BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 */

#ifndef __SYNC_PTR_H__
#define __SYNC_PTR_H__

namespace cbits
{

template< typename Lockable >
class sync_ptr
{
public:

    sync_ptr<Lockable>
    (
        Lockable* t,               
        const bool autofree=false  
    ) 
        : _t(t),_owned(true),_autofree(autofree)
    {
        _t->lock();
    }


    sync_ptr<Lockable>( const sync_ptr<Lockable>& r )
    {
        if( ! r._owned )
        {
            throw std::exception();
        }

        _t = r._t;
        _owned = true;
        _autofree = r._autofree;
        r.release();
    }


    sync_ptr<Lockable>& operator=( const sync_ptr<Lockable>& r )
    {
        if( ! r._owned )
        {
            throw std::exception();
        }

        if( _owned )
        {
            _t->unlock();
            if( _autofree )
            {
                delete _t;
            }
            _t = 0;
        }

        _t = r._t;
        _owned = true;
        _autofree = r._autofree;
        r.release();
        return *this;
    }


    bool operator==( const sync_ptr<Lockable>& r )
    {
        return _t == r._t;
    }


    Lockable* operator->()
    {
        return _t;
    }


    Lockable& operator*()
    {
        return *_t;
    }

    const bool isOwner() const
    {
        return _owned;
    }

    ~sync_ptr<Lockable>()
    {
        if( _owned )
        {
            _t->unlock();

            if( _autofree )
            {
                delete _t;
                _t = 0;
            }
        }
    }


private:

    void release() const
    {
        _owned    = false;  // don't unlock in destructor
        _autofree = false;  // don't delete obj in destructor
    }

    Lockable*     _t;           
    mutable bool  _owned;       
    mutable bool  _autofree;    
};

};

#endif

/*
 * $Id: sync_ptr.h,v 1.2 2002/10/14 01:21:04 brulow Exp $
 *
 * History: (Add nothing manually below)
 * -----------------------------------------------------------------------
 *
 * $Log: sync_ptr.h,v $
 * Revision 1.2  2002/10/14 01:21:04  brulow
 * Add unit tests for pointer pkg
 *
 * Revision 1.1  2002/10/13 17:17:45  brulow
 * Add a 'synchronizing' smart pointer
 *
 *
 */

---

Generated by

Hosted by