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boost/serialization/extended_type_info_typeid.hpp

#ifndef BOOST_SERIALIZATION_EXTENDED_TYPE_INFO_TYPEID_HPP
#define BOOST_SERIALIZATION_EXTENDED_TYPE_INFO_TYPEID_HPP

/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif

// extended_type_info_typeid.hpp: implementation for version that depends
// on runtime typing (rtti - typeid) but uses a user specified string
// as the portable class identifier.

// (C) Copyright 2002 Robert Ramey - http://www.rrsd.com . 
// Use, modification and distribution is subject to 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 for updates, documentation, and revision history.

#include <typeinfo>
#include <cstdarg>

#include <boost/config.hpp>

#include <boost/static_assert.hpp>
#include <boost/static_warning.hpp>
#include <boost/type_traits/is_polymorphic.hpp>
#include <boost/type_traits/remove_const.hpp>

#include <boost/serialization/singleton.hpp>
#include <boost/serialization/extended_type_info.hpp>
#include <boost/serialization/factory.hpp>

#include <boost/config/abi_prefix.hpp> // must be the last header
#ifdef BOOST_MSVC
#  pragma warning(push)
#  pragma warning(disable : 4251 4231 4660 4275)
#endif

namespace boost {
namespace serialization {
namespace detail {

class BOOST_SERIALIZATION_DECL(BOOST_PP_EMPTY()) extended_type_info_typeid_0 : 
    public extended_type_info
{
protected:
    const std::type_info * m_ti;
    extended_type_info_typeid_0();
    ~extended_type_info_typeid_0();
    void type_register(const std::type_info & ti);
    void type_unregister();
    const extended_type_info *
    get_extended_type_info(const std::type_info & ti) const;
public:
    virtual bool
    is_less_than(const extended_type_info &rhs) const;
    virtual bool
    is_equal(const extended_type_info &rhs) const;
    const std::type_info & get_typeid() const {
        return *m_ti;
    }
};

} // namespace detail

template<class T>
class extended_type_info_typeid : 
    public detail::extended_type_info_typeid_0,
    public singleton<extended_type_info_typeid<T> >
{
public:
    extended_type_info_typeid() :
        detail::extended_type_info_typeid_0()
    {
        type_register(typeid(T));
    }
    ~extended_type_info_typeid(){
        type_unregister();
    }
    // get the eti record for the true type of this record
    // relying upon standard type info implemenation (rtti)
    const extended_type_info *
    get_derived_extended_type_info(const T & t) const {
        // note: this implementation - based on usage of typeid (rtti)
        // only does something if the class has at least one virtual function.
        BOOST_STATIC_WARNING(boost::is_polymorphic<T>::value);
        return 
            detail::extended_type_info_typeid_0::get_extended_type_info(
                typeid(t)
            );
    }
    void * construct(unsigned int count, ...) const{
        // count up the arguments
        std::va_list ap;
        va_start(ap, count);
        switch(count){
        case 0:
            return factory<boost::remove_const<T>, 0>(ap);
        case 1:
            return factory<boost::remove_const<T>, 1>(ap);
        case 2:
            return factory<boost::remove_const<T>, 2>(ap);
        case 3:
            return factory<boost::remove_const<T>, 3>(ap);
        case 4:
            return factory<boost::remove_const<T>, 4>(ap);
        default:
            assert(false); // too many arguments
            // throw exception here?
            return NULL;
        }
    }
    void destroy(void const * const p) const{
        delete static_cast<T const *>(p) ;
    }
};

} // namespace serialization
} // namespace boost

///////////////////////////////////////////////////////////////////////////////
// If no other implementation has been designated as default, 
// use this one.  To use this implementation as the default, specify it
// before any of the other headers.
#ifndef BOOST_SERIALIZATION_DEFAULT_TYPE_INFO
    #define BOOST_SERIALIZATION_DEFAULT_TYPE_INFO
    namespace boost {
    namespace serialization {
    template<class T>
    struct extended_type_info_impl {
        typedef BOOST_DEDUCED_TYPENAME 
            boost::serialization::extended_type_info_typeid<T> type;
    };
    } // namespace serialization
    } // namespace boost
#endif

#ifdef BOOST_MSVC
#pragma warning(pop)
#endif
#include <boost/config/abi_suffix.hpp> // pops abi_suffix.hpp pragmas

#endif // BOOST_SERIALIZATION_EXTENDED_TYPE_INFO_TYPEID_HPP