blocxx

ReferenceBase.hpp

Go to the documentation of this file.
00001 /*******************************************************************************
00002 * Copyright (C) 2005, Vintela, Inc. All rights reserved.
00003 * Copyright (C) 2006, Novell, Inc. All rights reserved.
00004 * 
00005 * Redistribution and use in source and binary forms, with or without
00006 * modification, are permitted provided that the following conditions are met:
00007 * 
00008 *     * Redistributions of source code must retain the above copyright notice,
00009 *       this list of conditions and the following disclaimer.
00010 *     * Redistributions in binary form must reproduce the above copyright
00011 *       notice, this list of conditions and the following disclaimer in the
00012 *       documentation and/or other materials provided with the distribution.
00013 *     * Neither the name of 
00014 *       Vintela, Inc., 
00015 *       nor Novell, Inc., 
00016 *       nor the names of its contributors or employees may be used to 
00017 *       endorse or promote products derived from this software without 
00018 *       specific prior written permission.
00019 * 
00020 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
00021 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
00022 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
00023 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
00024 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
00025 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
00026 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00027 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00028 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
00029 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
00030 * POSSIBILITY OF SUCH DAMAGE.
00031 *******************************************************************************/
00032 
00033 
00038 #ifndef BLOCXX_REFERENCE_BASE_HPP_INCLUDE_GUARD_
00039 #define BLOCXX_REFERENCE_BASE_HPP_INCLUDE_GUARD_
00040 #include "blocxx/BLOCXX_config.h"
00041 #include "blocxx/RefCount.hpp"
00042 
00043 // The classes and functions defined in this file are not meant for general
00044 // use, they are internal implementation details.  They may change at any time.
00045 
00046 namespace BLOCXX_NAMESPACE
00047 {
00048 
00050 template<class T>
00051 inline void RefSwap(T& x, T&y)
00052 {
00053    T t = x;
00054    x = y;
00055    y = t;
00056 }
00058 // This class contains the non-templated code for Reference, to help 
00059 // minimize code bloat.
00060 class BLOCXX_COMMON_API ReferenceBase
00061 {
00062 #if !defined(__GNUC__) || __GNUC__ > 2 // because of a gcc 2.95 ICE
00063 protected:
00064 #else
00065 public:
00066 #endif
00067    ReferenceBase()
00068       : m_pRefCount(new RefCount) {}
00069    ReferenceBase(const ReferenceBase& arg)
00070       : m_pRefCount(0)
00071    {
00072       m_pRefCount = arg.m_pRefCount;
00073       m_pRefCount->inc();
00074    }
00075    void incRef()
00076    {
00077       m_pRefCount->inc();
00078    }
00079    
00080    bool decRef()
00081    {
00082       if (m_pRefCount->decAndTest())
00083       {
00084          delete m_pRefCount;
00085          return true;
00086       }
00087       return false;
00088    }
00089    void swap(ReferenceBase& arg)
00090    {
00091       RefSwap(m_pRefCount, arg.m_pRefCount);
00092    }
00093    void useRefCountOf(const ReferenceBase& arg)
00094    {
00095       decRef();
00096       m_pRefCount = arg.m_pRefCount;
00097       incRef();
00098    }
00099    
00100 #if !defined(__GNUC__) || __GNUC__ > 2 // because of a gcc 2.95 ICE
00101 protected:
00102 #else
00103 public:
00104 #endif
00105    RefCount* volatile m_pRefCount;
00106 };
00107 
00108 } // end namespace BLOCXX_NAMESPACE
00109 
00110 #endif
00111