| ///////////////////////////////////////////////////////////////////////////// |
| // |
| // (C) Copyright Ion Gaztanaga 2007-2009 |
| // |
| // 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/intrusive for documentation. |
| // |
| ///////////////////////////////////////////////////////////////////////////// |
| #ifndef BOOST_INTRUSIVE_DETAIL_PARENT_FROM_MEMBER_HPP |
| #define BOOST_INTRUSIVE_DETAIL_PARENT_FROM_MEMBER_HPP |
| |
| #include <boost/intrusive/detail/config_begin.hpp> |
| #include <cstddef> |
| |
| #if defined(BOOST_MSVC) || ((defined(_WIN32) || defined(__WIN32__) || defined(WIN32)) && defined(BOOST_INTEL)) |
| |
| #define BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER |
| #include <boost/cstdint.hpp> |
| #endif |
| |
| namespace boost { |
| namespace intrusive { |
| namespace detail { |
| |
| template<class Parent, class Member> |
| inline std::ptrdiff_t offset_from_pointer_to_member(const Member Parent::* ptr_to_member) |
| { |
| //The implementation of a pointer to member is compiler dependent. |
| #if defined(BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER) |
| //msvc compliant compilers use their the first 32 bits as offset (even in 64 bit mode) |
| return *(const boost::int32_t*)(void*)&ptr_to_member; |
| //This works with gcc, msvc, ac++, ibmcpp |
| #elif defined(__GNUC__) || defined(__HP_aCC) || defined(BOOST_INTEL) || \ |
| defined(__IBMCPP__) || defined(__DECCXX) |
| const Parent * const parent = 0; |
| const char *const member = reinterpret_cast<const char*>(&(parent->*ptr_to_member)); |
| return std::ptrdiff_t(member - reinterpret_cast<const char*>(parent)); |
| #else |
| //This is the traditional C-front approach: __MWERKS__, __DMC__, __SUNPRO_CC |
| return (*(const std::ptrdiff_t*)(void*)&ptr_to_member) - 1; |
| #endif |
| } |
| |
| template<class Parent, class Member> |
| inline Parent *parent_from_member(Member *member, const Member Parent::* ptr_to_member) |
| { |
| return (Parent*)((char*)member - offset_from_pointer_to_member(ptr_to_member)); |
| } |
| |
| template<class Parent, class Member> |
| inline const Parent *parent_from_member(const Member *member, const Member Parent::* ptr_to_member) |
| { |
| return (const Parent*)((const char*)member - offset_from_pointer_to_member(ptr_to_member)); |
| } |
| |
| } //namespace detail { |
| } //namespace intrusive { |
| } //namespace boost { |
| |
| #ifdef BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER |
| #undef BOOST_INTRUSIVE_MSVC_COMPLIANT_PTR_TO_MEMBER |
| #endif |
| |
| #include <boost/intrusive/detail/config_end.hpp> |
| |
| #endif //#ifndef BOOST_INTRUSIVE_DETAIL_PARENT_FROM_MEMBER_HPP |