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libs/serialization/example/portable_binary_iarchive.hpp

#ifndef PORTABLE_BINARY_IARCHIVE_HPP
#define PORTABLE_BINARY_IARCHIVE_HPP

// MS compatible compilers support #pragma once
#if defined(_MSC_VER) && (_MSC_VER >= 1020)
# pragma once
#endif

#if defined(_MSC_VER)
#pragma warning( push )
#pragma warning( disable : 4244 )
#endif

/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// portable_binary_iarchive.hpp

// (C) Copyright 2002-7 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 <istream>
#include <boost/serialization/string.hpp>
#include <boost/archive/archive_exception.hpp>
#include <boost/archive/basic_binary_iprimitive.hpp>
#include <boost/archive/detail/common_iarchive.hpp>
#include <boost/archive/shared_ptr_helper.hpp>
#include <boost/archive/detail/register_archive.hpp>

#include "portable_binary_archive.hpp"

/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// exception to be thrown if integer read from archive doesn't fit
// variable being loaded
class portable_binary_iarchive_exception : 
    public virtual boost::archive::archive_exception
{
public:
    typedef enum {
        incompatible_integer_size 
    } exception_code;
    portable_binary_iarchive_exception(exception_code c = incompatible_integer_size )
    {}
    virtual const char *what( ) const throw( )
    {
        const char *msg = "programmer error";
        switch(code){
        case incompatible_integer_size:
            msg = "integer cannot be represented";
        default:
            boost::archive::archive_exception::what();
        }
        return msg;
    }
};

/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
// "Portable" input binary archive.  It addresses integer size and endienness so 
// that binary archives can be passed across systems. Note:floating point types
// not addressed here
class portable_binary_iarchive :
    public boost::archive::basic_binary_iprimitive<
        portable_binary_iarchive,
        std::istream::char_type, 
        std::istream::traits_type
    >,
    public boost::archive::detail::common_iarchive<
        portable_binary_iarchive
    >
	,
    public boost::archive::detail::shared_ptr_helper
	{
    typedef boost::archive::basic_binary_iprimitive<
        portable_binary_iarchive,
        std::istream::char_type, 
        std::istream::traits_type
    > primitive_base_t;
    typedef boost::archive::detail::common_iarchive<
        portable_binary_iarchive
    > archive_base_t;
#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
public:
#else
    friend archive_base_t;
    friend primitive_base_t; // since with override load below
    friend class boost::archive::detail::interface_iarchive<
        portable_binary_iarchive
    >;
    friend class boost::archive::load_access;
protected:
#endif
    unsigned int m_flags;
    void load_impl(boost::intmax_t & l, char maxsize);

    // default fall through for any types not specified here
    template<class T>
    void load(T & t){
        boost::intmax_t l;
        load_impl(l, sizeof(T));
        // use cast to avoid compile time warning
        t = static_cast<T>(l);
    }
    void load(std::string & t){
        this->primitive_base_t::load(t);
    }
    #ifndef BOOST_NO_STD_WSTRING
    void load(std::wstring & t){
        this->primitive_base_t::load(t);
    }
    #endif
    void load(float & t){
        this->primitive_base_t::load(t);
        // floats not supported
        //BOOST_STATIC_ASSERT(false);
    }
    void load(double & t){
        this->primitive_base_t::load(t);
        // doubles not supported
        //BOOST_STATIC_ASSERT(false);
    }
    void load(char & t){
        this->primitive_base_t::load(t);
    }
    void load(unsigned char & t){
        this->primitive_base_t::load(t);
    }
    // intermediate level to support override of operators
    // fot templates in the absence of partial function 
    // template ordering
    typedef boost::archive::detail::common_iarchive<portable_binary_iarchive> 
        detail_common_iarchive;
    template<class T>
    void load_override(T & t, BOOST_PFTO int){
        this->detail_common_iarchive::load_override(t, 0);
    }
    void load_override(boost::archive::class_name_type & t, int);
    // binary files don't include the optional information 
    void load_override(
        boost::archive::class_id_optional_type & /* t */, 
        int
    ){}

    void init(unsigned int flags);
public:
    portable_binary_iarchive(std::istream & is, unsigned flags = 0) :
        primitive_base_t(
            * is.rdbuf(), 
            0 != (flags & boost::archive::no_codecvt)
        ),
        archive_base_t(flags),
        m_flags(0)
    {
        init(flags);
    }

    portable_binary_iarchive(
        std::basic_streambuf<
            std::istream::char_type, 
            std::istream::traits_type
        > & bsb, 
        unsigned int flags
    ) :
        primitive_base_t(
            bsb, 
            0 != (flags & boost::archive::no_codecvt)
        ),
        archive_base_t(flags),
        m_flags(0)
    {
        init(flags);
    }
};

// required by export in boost version > 1.34
#ifdef BOOST_SERIALIZATION_REGISTER_ARCHIVE
    BOOST_SERIALIZATION_REGISTER_ARCHIVE(portable_binary_iarchive)
#endif

// required by export in boost <= 1.34
#define BOOST_ARCHIVE_CUSTOM_IARCHIVE_TYPES portable_binary_iarchive

#if defined(_MSC_VER)
#pragma warning( pop )
#endif

#endif // PORTABLE_BINARY_IARCHIVE_HPP