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boost/system/detail/std_category.hpp

#ifndef BOOST_SYSTEM_DETAIL_STD_CATEGORY_HPP_INCLUDED
#define BOOST_SYSTEM_DETAIL_STD_CATEGORY_HPP_INCLUDED

// Support for interoperability between Boost.System and <system_error>
//
// Copyright 2018, 2021 Peter Dimov
//
// 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 library home page at http://www.boost.org/libs/system

#include <boost/system/detail/error_category.hpp>
#include <system_error>

//

namespace boost
{

namespace system
{

namespace detail
{

class BOOST_SYMBOL_VISIBLE std_category: public std::error_category
{
private:

    boost::system::error_category const * pc_;

public:

    boost::system::error_category const & original_category() const BOOST_NOEXCEPT
    {
        return *pc_;
    }

public:

    explicit std_category( boost::system::error_category const * pc, unsigned id ): pc_( pc )
    {
        if( id != 0 )
        {
#if defined(_MSC_VER) && defined(_CPPLIB_VER) && _MSC_VER >= 1900 && _MSC_VER < 2000

            // Poking into the protected _Addr member of std::error_category
            // is not a particularly good programming practice, but what can
            // you do

            _Addr = id;

#endif
        }
    }

    const char * name() const BOOST_NOEXCEPT BOOST_OVERRIDE
    {
        return pc_->name();
    }

    std::string message( int ev ) const BOOST_OVERRIDE
    {
        return pc_->message( ev );
    }

    std::error_condition default_error_condition( int ev ) const BOOST_NOEXCEPT BOOST_OVERRIDE
    {
        return pc_->default_error_condition( ev );
    }

    inline bool equivalent( int code, const std::error_condition & condition ) const BOOST_NOEXCEPT BOOST_OVERRIDE;
    inline bool equivalent( const std::error_code & code, int condition ) const BOOST_NOEXCEPT BOOST_OVERRIDE;
};

} // namespace detail

} // namespace system

} // namespace boost

#endif // #ifndef BOOST_SYSTEM_DETAIL_STD_CATEGORY_HPP_INCLUDED