opensync-plugin/src/fsmartptr.h

   1 ///
   2 /// \file       fsmartptr.h
   3 ///             C++ smart pointer template that can call unique free
   4 ///             functions.
   5 ///
   6
   7 /*
   8     Copyright (C) 2007,
   9         Net Direct Inc. (http://www.netdirect.ca/),
  10         and Chris Frey <cdfrey@foursquare.net>
  11
  12     This program is free software; you can redistribute it and/or modify
  13     it under the terms of the GNU General Public License as published by
  14     the Free Software Foundation; either version 2 of the License, or
  15     (at your option) any later version.
  16
  17     This program is distributed in the hope that it will be useful,
  18     but WITHOUT ANY WARRANTY; without even the implied warranty of
  19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  20
  21     See the GNU General Public License in the COPYING file at the
  22     root directory of this project for more details.
  23 */
  24
  25 #ifndef __REUSE_FSMARTPTR_H__
  26 #define __REUSE_FSMARTPTR_H__
  27
  28 // A special smart pointer for pointer handling.
  29 // Behaves like std::auto_ptr<> in that only one object
  30 // at a time owns the pointer, and destruction frees it.
  31 template <class T, class FT, void (*FreeFunc)(FT *pt)>
  32 class fSmartPtr
  33 {
  34         mutable T *m_pt;
  35
  36 public:
  37         fSmartPtr() : m_pt(0) {}
  38         fSmartPtr(T *pt) : m_pt(pt) {}
  39         fSmartPtr(const fSmartPtr &sp) : m_pt(sp.m_pt)
  40         {
  41                 sp.m_pt = 0;
  42         }
  43         ~fSmartPtr()
  44         {
  45                 if( m_pt )
  46                         FreeFunc(m_pt);
  47         }
  48
  49         fSmartPtr& operator=(T *pt)
  50         {
  51                 Extract();
  52                 m_pt = pt;
  53                 return *this;
  54         }
  55
  56         fSmartPtr& operator=(const fSmartPtr &sp)
  57         {
  58                 Extract();
  59                 m_pt = sp.Extract();
  60                 return *this;
  61         }
  62
  63         T* Extract()
  64         {
  65                 T *rp = m_pt;
  66                 m_pt = 0;
  67                 return rp;
  68         }
  69
  70         T* Get()
  71         {
  72                 return m_pt;
  73         }
  74 };
  75
  76 #endif
  77