| /* Copyright 2003-2008 Joaquin M Lopez Munoz. |
| * Distributed under the Boost Software License, Version 1.0. |
| * (See accompanying file LICENSE_1_0.txt or copy at |
| * http://www.boost.org/LICENSE_1_0.txt) |
| * |
| * See http://www.boost.org/libs/multi_index for library home page. |
| */ |
| |
| #ifndef BOOST_MULTI_INDEX_DETAIL_HEADER_HOLDER_HPP |
| #define BOOST_MULTI_INDEX_DETAIL_HEADER_HOLDER_HPP |
| |
| #if defined(_MSC_VER)&&(_MSC_VER>=1200) |
| #pragma once |
| #endif |
| |
| #include <boost/noncopyable.hpp> |
| |
| namespace boost{ |
| |
| namespace multi_index{ |
| |
| namespace detail{ |
| |
| /* A utility class used to hold a pointer to the header node. |
| * The base from member idiom is used because index classes, which are |
| * superclasses of multi_index_container, need this header in construction |
| * time. The allocation is made by the allocator of the multi_index_container |
| * class --hence, this allocator needs also be stored resorting |
| * to the base from member trick. |
| */ |
| |
| template<typename NodeTypePtr,typename Final> |
| struct header_holder:private noncopyable |
| { |
| header_holder():member(final().allocate_node()){} |
| ~header_holder(){final().deallocate_node(&*member);} |
| |
| NodeTypePtr member; |
| |
| private: |
| Final& final(){return *static_cast<Final*>(this);} |
| }; |
| |
| } /* namespace multi_index::detail */ |
| |
| } /* namespace multi_index */ |
| |
| } /* namespace boost */ |
| |
| #endif |