Chris@16: /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
Chris@16: 
Chris@16: // (C) Copyright 2002-4 Pavel Vozenilek . 
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: 
Chris@16: // Provides non-intrusive serialization for boost::optional.
Chris@16: 
Chris@16: #ifndef BOOST_SERIALIZATION_OPTIONAL_HPP_
Chris@16: #define BOOST_SERIALIZATION_OPTIONAL_HPP_
Chris@16: 
Chris@16: #if defined(_MSC_VER) && (_MSC_VER >= 1020)
Chris@16: # pragma once
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/config.hpp>
Chris@16: 
Chris@16: #include <boost/archive/detail/basic_iarchive.hpp>
Chris@16: 
Chris@16: #include <boost/optional.hpp>
Chris@16: #include <boost/serialization/item_version_type.hpp>
Chris@16: #include <boost/serialization/split_free.hpp>
Chris@16: #include <boost/serialization/level.hpp>
Chris@16: #include <boost/serialization/nvp.hpp>
Chris@16: #include <boost/serialization/version.hpp>
Chris@16: #include <boost/serialization/detail/stack_constructor.hpp>
Chris@16: 
Chris@16: // function specializations must be defined in the appropriate
Chris@16: // namespace - boost::serialization
Chris@16: namespace boost { 
Chris@16: namespace serialization {
Chris@16: 
Chris@16: template<class Archive, class T>
Chris@16: void save(
Chris@16:     Archive & ar, 
Chris@16:     const boost::optional< T > & t, 
Chris@16:     const unsigned int /*version*/
Chris@16: ){
Chris@16:     const bool tflag = t.is_initialized();
Chris@16:     ar << boost::serialization::make_nvp("initialized", tflag);
Chris@16:     if (tflag){
Chris@16:         const boost::serialization::item_version_type item_version(version< T >::value);
Chris@16:         #if 0
Chris@16:         const boost::archive::library_version_type library_version(
Chris@16:             ar.get_library_version()
Chris@16:         };
Chris@16:         if(boost::archive::library_version_type(3) < library_version){
Chris@16:             ar << BOOST_SERIALIZATION_NVP(item_version);
Chris@16:         }
Chris@16:         #else
Chris@16:             ar << BOOST_SERIALIZATION_NVP(item_version);
Chris@16:         #endif
Chris@16:         ar << boost::serialization::make_nvp("value", *t);
Chris@16:     }
Chris@16: }
Chris@16: 
Chris@16: template<class Archive, class T>
Chris@16: void load(
Chris@16:     Archive & ar, 
Chris@16:     boost::optional< T > & t, 
Chris@16:     const unsigned int /*version*/
Chris@16: ){
Chris@16:     bool tflag;
Chris@16:     ar >> boost::serialization::make_nvp("initialized", tflag);
Chris@16:     if (tflag){
Chris@16:         boost::serialization::item_version_type item_version(0);
Chris@16:         boost::archive::library_version_type library_version(
Chris@16:             ar.get_library_version()
Chris@16:         );
Chris@16:         if(boost::archive::library_version_type(3) < library_version){
Chris@16:             // item_version is handled as an attribute so it doesnt need an NVP
Chris@16:            ar >> BOOST_SERIALIZATION_NVP(item_version);
Chris@16:         }
Chris@16:         detail::stack_construct<Archive, T> aux(ar, item_version);
Chris@16:         ar >> boost::serialization::make_nvp("value", aux.reference());
Chris@16:         t.reset(aux.reference());
Chris@16:     }
Chris@16:     else {
Chris@16:         t.reset();
Chris@16:     }
Chris@16: }
Chris@16: 
Chris@16: template<class Archive, class T>
Chris@16: void serialize(
Chris@16:     Archive & ar, 
Chris@16:     boost::optional< T > & t, 
Chris@16:     const unsigned int version
Chris@16: ){
Chris@16:     boost::serialization::split_free(ar, t, version);
Chris@16: }
Chris@16: 
Chris@16: // the following would be slightly more efficient.  But it
Chris@16: // would mean that archives created with programs that support
Chris@16: // TPS wouldn't be readable by programs that don't support TPS.
Chris@16: // Hence we decline to support this otherwise convenient optimization.
Chris@16: //#ifndef BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION
Chris@16: #if 0
Chris@16: 
Chris@16: template <class T>
Chris@16: struct implementation_level<optional< T > >
Chris@16: {
Chris@16:     typedef mpl::integral_c_tag tag;
Chris@16:     typedef mpl::int_<boost::serialization::object_serializable> type;
Chris@16:     BOOST_STATIC_CONSTANT(
Chris@16:         int , 
Chris@16:         value = boost::serialization::implementation_level::type::value
Chris@16:     );
Chris@16: };
Chris@16: 
Chris@16: template<class T>
Chris@16: struct tracking_level<optional< T > >
Chris@16: {
Chris@16:     typedef mpl::integral_c_tag tag;
Chris@16:     typedef mpl::int_<boost::serialization::track_never> type;
Chris@16:     BOOST_STATIC_CONSTANT(
Chris@16:         int , 
Chris@16:         value = boost::serialization::tracking_level::type::value
Chris@16:     );
Chris@16: };
Chris@16: 
Chris@16: #endif
Chris@16: 
Chris@16: } // serialization
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #endif // BOOST_SERIALIZATION_OPTIONAL_HPP_