cond_dealtor.hpp

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// -*- C++ -*-

// Copyright (C) 2005 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) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.

// Permission to use, copy, modify, sell, and distribute this software
// is hereby granted without fee, provided that the above copyright
// notice appears in all copies, and that both that copyright notice and
// this permission notice appear in supporting documentation. None of
// the above authors, nor IBM Haifa Research Laboratories, make any
// representation about the suitability of this software for any
// purpose. It is provided "as is" without express or implied warranty.

/**
 * @file cond_dealtor.hpp
 * Contains a conditional deallocator.
 */

#ifndef COND_DEALTOR_HPP
#define COND_DEALTOR_HPP

namespace pb_assoc
{

  namespace detail
  {

#define PB_ASSOC_COND_DEALTOR_CLASS_T_DEC \
	template<class Entry, class Allocator>

#define PB_ASSOC_COND_DEALTOR_CLASS_C_DEC \
	cond_dealtor< \
		Entry, \
		Allocator>

    template<class Entry, class Allocator>
    class cond_dealtor
    {
    public:
      typedef
      typename Allocator::template rebind<Entry>::other
      entry_allocator;

      typedef typename entry_allocator::pointer entry_pointer;

    public:
      inline
      cond_dealtor(entry_pointer p_e);

      inline
      ~cond_dealtor();

      inline void
      set_no_action();

    private:
      entry_pointer m_p_e;

      bool m_no_action_destructor;

      static entry_allocator s_alloc;
    };

    PB_ASSOC_COND_DEALTOR_CLASS_T_DEC
    typename PB_ASSOC_COND_DEALTOR_CLASS_C_DEC::entry_allocator
    PB_ASSOC_COND_DEALTOR_CLASS_C_DEC::s_alloc;

    PB_ASSOC_COND_DEALTOR_CLASS_T_DEC
    inline
    PB_ASSOC_COND_DEALTOR_CLASS_C_DEC::
    cond_dealtor(entry_pointer p_e) :
      m_p_e(p_e),
      m_no_action_destructor(false)
    { }

    PB_ASSOC_COND_DEALTOR_CLASS_T_DEC
    inline void
    PB_ASSOC_COND_DEALTOR_CLASS_C_DEC::
    set_no_action()
    {
      m_no_action_destructor = true;
    }

    PB_ASSOC_COND_DEALTOR_CLASS_T_DEC
    inline
    PB_ASSOC_COND_DEALTOR_CLASS_C_DEC::
    ~cond_dealtor()
    {
      if (m_no_action_destructor)
	return;

      s_alloc.deallocate(m_p_e, 1);
    }

#undef PB_ASSOC_COND_DEALTOR_CLASS_T_DEC
#undef PB_ASSOC_COND_DEALTOR_CLASS_C_DEC

  } // namespace detail

} // namespace pb_assoc

#endif // #ifndef COND_DEALTOR_HPP