| //----------------------------------------------------------------------------- |
| // boost aligned_storage.hpp header file |
| // See http://www.boost.org for updates, documentation, and revision history. |
| //----------------------------------------------------------------------------- |
| // |
| // Copyright (c) 2002-2003 |
| // Eric Friedman, Itay Maman |
| // |
| // 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) |
| |
| #ifndef BOOST_TT_ALIGNED_STORAGE_HPP |
| #define BOOST_TT_ALIGNED_STORAGE_HPP |
| |
| #include <cstddef> // for std::size_t |
| |
| #include <boost/config.hpp> |
| #include <boost/detail/workaround.hpp> |
| #include <boost/type_traits/alignment_of.hpp> |
| #include <boost/type_traits/type_with_alignment.hpp> |
| #include <boost/type_traits/is_pod.hpp> |
| #include <boost/type_traits/conditional.hpp> |
| |
| namespace boost { |
| |
| namespace detail { namespace aligned_storage { |
| |
| BOOST_STATIC_CONSTANT( |
| std::size_t |
| , alignment_of_max_align = ::boost::alignment_of<boost::detail::max_align>::value |
| ); |
| |
| // |
| // To be TR1 conforming this must be a POD type: |
| // |
| template < |
| std::size_t size_ |
| , std::size_t alignment_ |
| > |
| struct aligned_storage_imp |
| { |
| union data_t |
| { |
| char buf[size_]; |
| |
| typename ::boost::type_with_alignment<alignment_>::type align_; |
| } data_; |
| void* address() const { return const_cast<aligned_storage_imp*>(this); } |
| }; |
| template <std::size_t size> |
| struct aligned_storage_imp<size, std::size_t(-1)> |
| { |
| union data_t |
| { |
| char buf[size]; |
| ::boost::detail::max_align align_; |
| } data_; |
| void* address() const { return const_cast<aligned_storage_imp*>(this); } |
| }; |
| |
| template< std::size_t alignment_ > |
| struct aligned_storage_imp<0u,alignment_> |
| { |
| /* intentionally empty */ |
| void* address() const { return 0; } |
| }; |
| |
| }} // namespace detail::aligned_storage |
| |
| template < |
| std::size_t size_ |
| , std::size_t alignment_ = std::size_t(-1) |
| > |
| class aligned_storage : |
| #ifndef __BORLANDC__ |
| private |
| #else |
| public |
| #endif |
| ::boost::detail::aligned_storage::aligned_storage_imp<size_, alignment_> |
| { |
| |
| public: // constants |
| |
| typedef ::boost::detail::aligned_storage::aligned_storage_imp<size_, alignment_> type; |
| |
| BOOST_STATIC_CONSTANT( |
| std::size_t |
| , size = size_ |
| ); |
| BOOST_STATIC_CONSTANT( |
| std::size_t |
| , alignment = ( |
| alignment_ == std::size_t(-1) |
| ? ::boost::detail::aligned_storage::alignment_of_max_align |
| : alignment_ |
| ) |
| ); |
| |
| private: // noncopyable |
| |
| aligned_storage(const aligned_storage&); |
| aligned_storage& operator=(const aligned_storage&); |
| |
| public: // structors |
| |
| aligned_storage() |
| { |
| } |
| |
| ~aligned_storage() |
| { |
| } |
| |
| public: // accessors |
| |
| void* address() |
| { |
| return static_cast<type*>(this)->address(); |
| } |
| |
| const void* address() const |
| { |
| return static_cast<const type*>(this)->address(); |
| } |
| }; |
| |
| // |
| // Make sure that is_pod recognises aligned_storage<>::type |
| // as a POD (Note that aligned_storage<> itself is not a POD): |
| // |
| template <std::size_t size_, std::size_t alignment_> |
| struct is_pod< ::boost::detail::aligned_storage::aligned_storage_imp<size_, alignment_> > : public true_type{}; |
| |
| } // namespace boost |
| |
| #endif // BOOST_ALIGNED_STORAGE_HPP |