Chris@16: #ifndef  BOOST_SERIALIZATION_VOID_CAST_HPP
Chris@16: #define BOOST_SERIALIZATION_VOID_CAST_HPP
Chris@16: 
Chris@16: // MS compatible compilers support #pragma once
Chris@101: #if defined(_MSC_VER)
Chris@16: # pragma once
Chris@16: #endif
Chris@16: 
Chris@16: /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
Chris@16: // void_cast.hpp:   interface for run-time casting of void pointers.
Chris@16: 
Chris@16: // (C) Copyright 2002-2009 Robert Ramey - http://www.rrsd.com . 
Chris@16: // Use, modification and distribution is subject to the Boost Software
Chris@16: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: // gennadiy.rozental@tfn.com
Chris@16: 
Chris@16: //  See http://www.boost.org for updates, documentation, and revision history.
Chris@16: 
Chris@16: #include <cstddef> // for ptrdiff_t
Chris@16: #include <boost/config.hpp>
Chris@16: #include <boost/noncopyable.hpp>
Chris@16: 
Chris@16: #include <boost/serialization/smart_cast.hpp>
Chris@16: #include <boost/serialization/singleton.hpp>
Chris@16: #include <boost/serialization/force_include.hpp>
Chris@16: #include <boost/serialization/type_info_implementation.hpp>
Chris@16: #include <boost/serialization/extended_type_info.hpp>
Chris@16: #include <boost/type_traits/is_virtual_base_of.hpp>
Chris@16: #include <boost/serialization/void_cast_fwd.hpp>
Chris@16: 
Chris@16: #include <boost/serialization/config.hpp>
Chris@16: #include <boost/config/abi_prefix.hpp> // must be the last header
Chris@16: 
Chris@16: #ifdef BOOST_MSVC
Chris@16: #  pragma warning(push)
Chris@16: #  pragma warning(disable : 4251 4231 4660 4275)
Chris@16: #endif
Chris@16: 
Chris@16: namespace boost { 
Chris@16: namespace serialization { 
Chris@16: 
Chris@16: class extended_type_info;
Chris@16: 
Chris@16: // Given a void *, assume that it really points to an instance of one type
Chris@16: // and alter it so that it would point to an instance of a related type.
Chris@16: // Return the altered pointer. If there exists no sequence of casts that
Chris@16: // can transform from_type to to_type, return a NULL.  
Chris@16: 
Chris@16: BOOST_SERIALIZATION_DECL(void const *)
Chris@16: void_upcast(
Chris@16:     extended_type_info const & derived,  
Chris@16:     extended_type_info const & base, 
Chris@16:     void const * const t
Chris@16: );
Chris@16: 
Chris@16: inline void *
Chris@16: void_upcast(
Chris@16:     extended_type_info const & derived,
Chris@16:     extended_type_info const & base,
Chris@16:     void * const t 
Chris@16: ){
Chris@16:     return const_cast<void*>(void_upcast(
Chris@16:         derived, 
Chris@16:         base, 
Chris@16:         const_cast<void const *>(t)
Chris@16:     ));
Chris@16: }
Chris@16: 
Chris@16: BOOST_SERIALIZATION_DECL(void const *)
Chris@16: void_downcast(
Chris@16:     extended_type_info const & derived,  
Chris@16:     extended_type_info const & base, 
Chris@16:     void const * const t
Chris@16: );
Chris@16: 
Chris@16: inline void *
Chris@16: void_downcast(
Chris@16:     extended_type_info const & derived,
Chris@16:     extended_type_info const & base,
Chris@16:     void * const t 
Chris@16: ){
Chris@16:     return const_cast<void*>(void_downcast(
Chris@16:         derived, 
Chris@16:         base, 
Chris@16:         const_cast<void const *>(t)
Chris@16:     ));
Chris@16: }
Chris@16: 
Chris@16: namespace void_cast_detail {
Chris@16: 
Chris@16: class BOOST_SERIALIZATION_DECL(BOOST_PP_EMPTY()) void_caster :
Chris@16:     private boost::noncopyable
Chris@16: {
Chris@16:     friend 
Chris@16:     BOOST_SERIALIZATION_DECL(void const *)
Chris@16:     boost::serialization::void_upcast(
Chris@16:         extended_type_info const & derived,
Chris@16:         extended_type_info const & base,
Chris@16:         void const * const
Chris@16:     );
Chris@16:     friend 
Chris@16:     BOOST_SERIALIZATION_DECL(void const *)  
Chris@16:     boost::serialization::void_downcast(
Chris@16:         extended_type_info const & derived,
Chris@16:         extended_type_info const & base,
Chris@16:         void const * const
Chris@16:     );
Chris@16: protected:
Chris@16:     void recursive_register(bool includes_virtual_base = false) const;
Chris@16:     void recursive_unregister() const;
Chris@16:     virtual bool has_virtual_base() const = 0;
Chris@16: public:
Chris@16:     // Data members
Chris@16:     const extended_type_info * m_derived;
Chris@16:     const extended_type_info * m_base;
Chris@16:     /*const*/ std::ptrdiff_t m_difference;
Chris@16:     void_caster const * const m_parent;
Chris@16: 
Chris@16:     // note that void_casters are keyed on value of
Chris@16:     // member extended type info records - NOT their
Chris@16:     // addresses.  This is necessary in order for the
Chris@16:     // void cast operations to work across dll and exe
Chris@16:     // module boundries.
Chris@16:     bool operator<(const void_caster & rhs) const;
Chris@16: 
Chris@16:     const void_caster & operator*(){
Chris@16:         return *this;
Chris@16:     }
Chris@16:     // each derived class must re-implement these;
Chris@16:     virtual void const * upcast(void const * const t) const = 0;
Chris@16:     virtual void const * downcast(void const * const t) const = 0;
Chris@16:     // Constructor
Chris@16:     void_caster(
Chris@16:         extended_type_info const * derived,
Chris@16:         extended_type_info const * base,
Chris@16:         std::ptrdiff_t difference = 0,
Chris@16:         void_caster const * const parent = 0
Chris@16:     ) :
Chris@16:         m_derived(derived),
Chris@16:         m_base(base),
Chris@16:         m_difference(difference),
Chris@16:         m_parent(parent)
Chris@16:     {}
Chris@16:     virtual ~void_caster(){}
Chris@16: };
Chris@16: 
Chris@16: #ifdef BOOST_MSVC
Chris@16: #  pragma warning(push)
Chris@16: #  pragma warning(disable : 4251 4231 4660 4275 4511 4512)
Chris@16: #endif
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: class void_caster_primitive : 
Chris@16:     public void_caster
Chris@16: {
Chris@16:     virtual void const * downcast(void const * const t) const {
Chris@16:         const Derived * d = 
Chris@16:             boost::serialization::smart_cast<const Derived *, const Base *>(
Chris@16:                 static_cast<const Base *>(t)
Chris@16:             );
Chris@16:         return d;
Chris@16:     }
Chris@16:     virtual void const * upcast(void const * const t) const {
Chris@16:         const Base * b = 
Chris@16:             boost::serialization::smart_cast<const Base *, const Derived *>(
Chris@16:                 static_cast<const Derived *>(t)
Chris@16:             );
Chris@16:         return b;
Chris@16:     }
Chris@16:     virtual bool has_virtual_base() const {
Chris@16:         return false;
Chris@16:     }
Chris@16: public:
Chris@16:     void_caster_primitive();
Chris@16:     virtual ~void_caster_primitive();
Chris@16: };
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: void_caster_primitive<Derived, Base>::void_caster_primitive() :
Chris@16:     void_caster( 
Chris@16:         & type_info_implementation<Derived>::type::get_const_instance(), 
Chris@16:         & type_info_implementation<Base>::type::get_const_instance(),
Chris@101:         // note:I wanted to displace from 0 here, but at least one compiler
Chris@16:         // treated 0 by not shifting it at all.
Chris@16:         reinterpret_cast<std::ptrdiff_t>(
Chris@16:             static_cast<Derived *>(
Chris@101:                 reinterpret_cast<Base *>(8)
Chris@16:             )
Chris@101:         ) - 8
Chris@16:     )
Chris@16: {
Chris@16:     recursive_register();
Chris@16: }
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: void_caster_primitive<Derived, Base>::~void_caster_primitive(){
Chris@16:     recursive_unregister();
Chris@16: }
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: class void_caster_virtual_base : 
Chris@16:     public void_caster
Chris@16: {
Chris@16:     virtual bool has_virtual_base() const {
Chris@16:         return true;
Chris@16:     }
Chris@16: public:
Chris@16:     virtual void const * downcast(void const * const t) const {
Chris@16:         const Derived * d = 
Chris@16:             dynamic_cast<const Derived *>(
Chris@16:                 static_cast<const Base *>(t)
Chris@16:             );
Chris@16:         return d;
Chris@16:     }
Chris@16:     virtual void const * upcast(void const * const t) const {
Chris@16:         const Base * b = 
Chris@16:             dynamic_cast<const Base *>(
Chris@16:                 static_cast<const Derived *>(t)
Chris@16:             );
Chris@16:         return b;
Chris@16:     }
Chris@16:     void_caster_virtual_base();
Chris@16:     virtual ~void_caster_virtual_base();
Chris@16: };
Chris@16: 
Chris@16: #ifdef BOOST_MSVC
Chris@16: #pragma warning(pop)
Chris@16: #endif
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: void_caster_virtual_base<Derived,Base>::void_caster_virtual_base() :
Chris@16:     void_caster( 
Chris@16:         & (type_info_implementation<Derived>::type::get_const_instance()), 
Chris@16:         & (type_info_implementation<Base>::type::get_const_instance())
Chris@16:     )
Chris@16: {
Chris@16:     recursive_register(true);
Chris@16: }
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: void_caster_virtual_base<Derived,Base>::~void_caster_virtual_base(){
Chris@16:     recursive_unregister();
Chris@16: }
Chris@16: 
Chris@16: template <class Derived, class Base>
Chris@16: struct void_caster_base :
Chris@16:     public void_caster
Chris@16: {
Chris@16:     typedef
Chris@101:         typename mpl::eval_if<boost::is_virtual_base_of<Base,Derived>,
Chris@16:             mpl::identity<
Chris@16:                 void_cast_detail::void_caster_virtual_base<Derived, Base>
Chris@16:             >
Chris@16:         ,// else
Chris@16:             mpl::identity<
Chris@16:                 void_cast_detail::void_caster_primitive<Derived, Base>
Chris@16:             >
Chris@16:         >::type type;
Chris@16: };
Chris@16: 
Chris@16: } // void_cast_detail 
Chris@16: 
Chris@16: template<class Derived, class Base>
Chris@16: BOOST_DLLEXPORT 
Chris@16: inline const void_cast_detail::void_caster & void_cast_register(
Chris@16:     Derived const * /* dnull = NULL */, 
Chris@16:     Base const * /* bnull = NULL */
Chris@16: ){
Chris@16:     typedef
Chris@101:         typename mpl::eval_if<boost::is_virtual_base_of<Base,Derived>,
Chris@16:             mpl::identity<
Chris@16:                 void_cast_detail::void_caster_virtual_base<Derived, Base>
Chris@16:             >
Chris@16:         ,// else
Chris@16:             mpl::identity<
Chris@16:                 void_cast_detail::void_caster_primitive<Derived, Base>
Chris@16:             >
Chris@16:         >::type typex;
Chris@16:     return singleton<typex>::get_const_instance();
Chris@16: }
Chris@16: 
Chris@16: template<class Derived, class Base>
Chris@16: class void_caster :
Chris@16:     public void_cast_detail::void_caster_base<Derived, Base>::type
Chris@16: {
Chris@16: };
Chris@16: 
Chris@16: } // namespace serialization
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #ifdef BOOST_MSVC  
Chris@16: #  pragma warning(pop)  
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/config/abi_suffix.hpp> // pops abi_suffix.hpp pragmas
Chris@16: 
Chris@16: #endif // BOOST_SERIALIZATION_VOID_CAST_HPP