memory

Go to the documentation of this file.

// <memory> -*- C++ -*-

// Copyright (C) 2001, 2002, 2004 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library 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, or (at your option)
// any later version.

// This library 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 library; see the file COPYING.  If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/*
 * Copyright (c) 1997-1999
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 */

#ifndef _GLIBCXX_MEMORY
#define _GLIBCXX_MEMORY 1

#pragma GCC system_header

#include <bits/stl_algobase.h>
#include <bits/allocator.h>
#include <bits/stl_construct.h>
#include <bits/stl_iterator_base_types.h> //for iterator_traits
#include <bits/stl_uninitialized.h>
#include <bits/stl_raw_storage_iter.h>
#include <debug/debug.h>
#include <limits>

namespace std
{
  template<typename _Tp>
    pair<_Tp*, ptrdiff_t>
    __get_temporary_buffer(ptrdiff_t __len, _Tp*)
    {
      const ptrdiff_t __max = numeric_limits<ptrdiff_t>::max() / sizeof(_Tp);
      if (__len > __max)
    __len = __max;
      
      while (__len > 0) 
    {
      _Tp* __tmp = static_cast<_Tp*>(::operator new(__len * sizeof(_Tp), 
                            nothrow));
      if (__tmp != 0)
        return pair<_Tp*, ptrdiff_t>(__tmp, __len);
      __len /= 2;
    }
      return pair<_Tp*, ptrdiff_t>(static_cast<_Tp*>(0), 0);
    }

  template<typename _Tp>
    inline pair<_Tp*, ptrdiff_t>
    get_temporary_buffer(ptrdiff_t __len)
    { return std::__get_temporary_buffer(__len, static_cast<_Tp*>(0)); }

  template<typename _Tp>
    void
    return_temporary_buffer(_Tp* __p)
    { ::operator delete(__p, nothrow); }

  template<typename _Tp1>
    struct auto_ptr_ref
    {
      _Tp1* _M_ptr;
      
      explicit
      auto_ptr_ref(_Tp1* __p): _M_ptr(__p) { }
    };


  template<typename _Tp>
    class auto_ptr
    {
    private:
      _Tp* _M_ptr;
      
    public:
      typedef _Tp element_type;
      
      explicit
      auto_ptr(element_type* __p = 0) throw() : _M_ptr(__p) { }

      auto_ptr(auto_ptr& __a) throw() : _M_ptr(__a.release()) { }

      template<typename _Tp1>
        auto_ptr(auto_ptr<_Tp1>& __a) throw() : _M_ptr(__a.release()) { }

      auto_ptr&
      operator=(auto_ptr& __a) throw()
      {
    reset(__a.release());
    return *this;
      }

      template<typename _Tp1>
        auto_ptr&
        operator=(auto_ptr<_Tp1>& __a) throw()
        {
      reset(__a.release());
      return *this;
    }

      ~auto_ptr() { delete _M_ptr; }
      
      element_type&
      operator*() const throw() 
      {
    _GLIBCXX_DEBUG_ASSERT(_M_ptr != 0);
    return *_M_ptr; 
      }
      
      element_type*
      operator->() const throw() 
      {
    _GLIBCXX_DEBUG_ASSERT(_M_ptr != 0);
    return _M_ptr; 
      }
      
      element_type*
      get() const throw() { return _M_ptr; }
      
      element_type*
      release() throw()
      {
    element_type* __tmp = _M_ptr;
    _M_ptr = 0;
    return __tmp;
      }
      
      void
      reset(element_type* __p = 0) throw()
      {
    if (__p != _M_ptr)
      {
        delete _M_ptr;
        _M_ptr = __p;
      }
      }
      
      auto_ptr(auto_ptr_ref<element_type> __ref) throw()
      : _M_ptr(__ref._M_ptr) { }
      
      auto_ptr&
      operator=(auto_ptr_ref<element_type> __ref) throw()
      {
    if (__ref._M_ptr != this->get())
      {
        delete _M_ptr;
        _M_ptr = __ref._M_ptr;
      }
    return *this;
      }
      
      template<typename _Tp1>
        operator auto_ptr_ref<_Tp1>() throw()
        { return auto_ptr_ref<_Tp1>(this->release()); }

      template<typename _Tp1>
        operator auto_ptr<_Tp1>() throw()
        { return auto_ptr<_Tp1>(this->release()); }
  };
} // namespace std

#endif /* _GLIBCXX_MEMORY */

---