#ifndef BOOST_SYSTEM_ERROR_CODE_HPP_INCLUDED
#define BOOST_SYSTEM_ERROR_CODE_HPP_INCLUDED

//  Copyright Beman Dawes 2006, 2007
//  Copyright Christoper Kohlhoff 2007
//  Copyright Peter Dimov 2017, 2018
//
//  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/is_error_code_enum.hpp>
#include <boost/system/is_error_condition_enum.hpp>
#include <boost/system/detail/errc.hpp>
#include <boost/system/detail/error_category.hpp>
#include <boost/system/detail/generic_category.hpp>
#include <boost/system/detail/system_category.hpp>
#include <boost/system/detail/enable_if.hpp>
#include <boost/system/detail/error_condition.hpp>
#include <boost/system/detail/error_code.hpp>
#include <boost/system/api_config.hpp>
#include <boost/system/detail/config.hpp>
#include <boost/cstdint.hpp>
#include <boost/config.hpp>
#include <ostream>
#include <string>
#include <functional>
#include <cstring>

#if defined(BOOST_SYSTEM_HAS_SYSTEM_ERROR)
# include <system_error>
#endif

#if !defined(BOOST_POSIX_API) && !defined(BOOST_WINDOWS_API)
#  error BOOST_POSIX_API or BOOST_WINDOWS_API must be defined
#endif

namespace boost
{

namespace system
{

class error_code;         // values defined by the operating system
class error_condition;    // portable generic values defined below, but ultimately
                          // based on the POSIX standard

}  // namespace system

// boost::throws()

namespace detail
{

//  Misuse of the error_code object is turned into a noisy failure by
//  poisoning the reference. This particular implementation doesn't
//  produce warnings or errors from popular compilers, is very efficient
//  (as determined by inspecting generated code), and does not suffer
//  from order of initialization problems. In practice, it also seems
//  cause user function error handling implementation errors to be detected
//  very early in the development cycle.

inline system::error_code* throws()
{
    // See github.com/boostorg/system/pull/12 by visigoth for why the return
    // is poisoned with nonzero rather than (0). A test, test_throws_usage(),
    // has been added to error_code_test.cpp, and as visigoth mentioned it
    // fails on clang for release builds with a return of 0 but works fine
    // with (1).
    // Since the undefined behavior sanitizer (-fsanitize=undefined) does not
    // allow a reference to be formed to the unaligned address of (1), we use
    // (8) instead.

    return reinterpret_cast<system::error_code*>(8);
}

} // namespace detail

inline system::error_code& throws()
{
    return *detail::throws();
}

// non-member functions of error_code and error_condition

namespace system
{

inline bool operator==( const error_code & code, const error_condition & condition ) BOOST_NOEXCEPT
{
    return code.category().equivalent( code.value(), condition ) || condition.category().equivalent( code, condition.value() );
}

inline bool operator!=( const error_code & lhs, const error_condition & rhs ) BOOST_NOEXCEPT
{
    return !( lhs == rhs );
}

inline bool operator==( const error_condition & condition, const error_code & code ) BOOST_NOEXCEPT
{
    return code.category().equivalent( code.value(), condition ) || condition.category().equivalent( code, condition.value() );
}

inline bool operator!=( const error_condition & lhs, const error_code & rhs ) BOOST_NOEXCEPT
{
    return !( lhs == rhs );
}

// make_* functions for errc::errc_t

namespace errc
{

// explicit conversion:
BOOST_SYSTEM_CONSTEXPR inline error_code make_error_code( errc_t e ) BOOST_NOEXCEPT
{
    return error_code( e, generic_category() );
}

// implicit conversion:
BOOST_SYSTEM_CONSTEXPR inline error_condition make_error_condition( errc_t e ) BOOST_NOEXCEPT
{
    return error_condition( e, generic_category() );
}

} // namespace errc

// error_category default implementation

inline error_condition error_category::default_error_condition( int ev ) const BOOST_NOEXCEPT
{
    return error_condition( ev, *this );
}

inline bool error_category::equivalent( int code, const error_condition & condition ) const BOOST_NOEXCEPT
{
    return default_error_condition( code ) == condition;
}

inline bool error_category::equivalent( const error_code & code, int condition ) const BOOST_NOEXCEPT
{
    return *this == code.category() && code.value() == condition;
}

inline char const * error_category::message( int ev, char * buffer, std::size_t len ) const BOOST_NOEXCEPT
{
    if( len == 0 )
    {
        return buffer;
    }

    if( len == 1 )
    {
        buffer[0] = 0;
        return buffer;
    }

#if !defined(BOOST_NO_EXCEPTIONS)
    try
#endif
    {
        std::string m = this->message( ev );

# if defined( BOOST_MSVC )
#  pragma warning( push )
#  pragma warning( disable: 4996 )
# elif defined(__clang__) && defined(__has_warning)
#  pragma clang diagnostic push
#  if __has_warning("-Wdeprecated-declarations")
#   pragma clang diagnostic ignored "-Wdeprecated-declarations"
#  endif
# endif

        std::strncpy( buffer, m.c_str(), len - 1 );
        buffer[ len-1 ] = 0;

# if defined( BOOST_MSVC )
#  pragma warning( pop )
# elif defined(__clang__) && defined(__has_warning)
#  pragma clang diagnostic pop
# endif

        return buffer;
    }
#if !defined(BOOST_NO_EXCEPTIONS)
    catch( ... )
    {
        return "Message text unavailable";
    }
#endif
}

} // namespace system

} // namespace boost

// system_error_category implementation

#if defined(BOOST_WINDOWS_API)

#include <boost/system/detail/system_category_win32.hpp>

inline boost::system::error_condition boost::system::detail::system_error_category::default_error_condition( int ev ) const BOOST_NOEXCEPT
{
    return system_category_default_error_condition_win32( ev );
}

inline std::string boost::system::detail::system_error_category::message( int ev ) const
{
    return system_category_message_win32( ev );
}

inline char const * boost::system::detail::system_error_category::message( int ev, char * buffer, std::size_t len ) const BOOST_NOEXCEPT
{
    return system_category_message_win32( ev, buffer, len );
}

#else // #if defined(BOOST_WINDOWS_API)

#include <boost/system/detail/system_category_posix.hpp>

inline boost::system::error_condition boost::system::detail::system_error_category::default_error_condition( int ev ) const BOOST_NOEXCEPT
{
    return system_category_default_error_condition_posix( ev );
}

inline std::string boost::system::detail::system_error_category::message( int ev ) const
{
    return generic_error_category_message( ev );
}

inline char const * boost::system::detail::system_error_category::message( int ev, char * buffer, std::size_t len ) const BOOST_NOEXCEPT
{
    return generic_error_category_message( ev, buffer, len );
}

#endif // #if defined(BOOST_WINDOWS_API)

// interoperability with std::error_code, std::error_condition

#if defined(BOOST_SYSTEM_HAS_SYSTEM_ERROR)

#include <boost/system/detail/std_interoperability.hpp>

inline boost::system::error_category::operator std::error_category const & () const
{
    return boost::system::detail::to_std_category( *this );
}

#endif // #if defined(BOOST_SYSTEM_HAS_SYSTEM_ERROR)

#endif // BOOST_SYSTEM_ERROR_CODE_HPP_INCLUDED