#ifndef BOOST_ENDIAN_DETAIL_ENDIAN_STORE_HPP_INCLUDED #define BOOST_ENDIAN_DETAIL_ENDIAN_STORE_HPP_INCLUDED // Copyright 2019 Peter Dimov // // Distributed under the Boost Software License, Version 1.0. // http://www.boost.org/LICENSE_1_0.txt #include <boost/endian/detail/endian_reverse.hpp> #include <boost/endian/detail/order.hpp> #include <boost/endian/detail/integral_by_size.hpp> #include <boost/endian/detail/is_trivially_copyable.hpp> #include <boost/type_traits/is_integral.hpp> #include <boost/type_traits/is_enum.hpp> #include <boost/static_assert.hpp> #include <cstddef> #include <cstring> namespace boost { namespace endian { namespace detail { template<class T, std::size_t N1, BOOST_SCOPED_ENUM(order) O1, std::size_t N2, BOOST_SCOPED_ENUM(order) O2> struct endian_store_impl { }; } // namespace detail // Requires: // // sizeof(T) must be 1, 2, 4, or 8 // 1 <= N <= sizeof(T) // T is TriviallyCopyable // if N < sizeof(T), T is integral or enum template<class T, std::size_t N, BOOST_SCOPED_ENUM(order) Order> inline void endian_store( unsigned char * p, T const & v ) BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( sizeof(T) == 1 || sizeof(T) == 2 || sizeof(T) == 4 || sizeof(T) == 8 ); BOOST_STATIC_ASSERT( N >= 1 && N <= sizeof(T) ); return detail::endian_store_impl<T, sizeof(T), order::native, N, Order>()( p, v ); } namespace detail { // same endianness, same size template<class T, std::size_t N, BOOST_SCOPED_ENUM(order) O> struct endian_store_impl<T, N, O, N, O> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_trivially_copyable<T>::value ); std::memcpy( p, &v, N ); } }; // same size, reverse endianness template<class T, std::size_t N, BOOST_SCOPED_ENUM(order) O1, BOOST_SCOPED_ENUM(order) O2> struct endian_store_impl<T, N, O1, N, O2> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_trivially_copyable<T>::value ); typename integral_by_size<N>::type tmp; std::memcpy( &tmp, &v, N ); endian_reverse_inplace( tmp ); std::memcpy( p, &tmp, N ); } }; // truncating store 2 -> 1 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 2, Order, 1, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 2 ]; boost::endian::endian_store<T, 2, order::little>( tmp, v ); p[0] = tmp[0]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 2, Order, 1, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 2 ]; boost::endian::endian_store<T, 2, order::big>( tmp, v ); p[0] = tmp[1]; } }; // truncating store 4 -> 1 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 4, Order, 1, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 4 ]; boost::endian::endian_store<T, 4, order::little>( tmp, v ); p[0] = tmp[0]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 4, Order, 1, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 4 ]; boost::endian::endian_store<T, 4, order::big>( tmp, v ); p[0] = tmp[3]; } }; // truncating store 4 -> 2 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 4, Order, 2, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 4 ]; boost::endian::endian_store<T, 4, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 4, Order, 2, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 4 ]; boost::endian::endian_store<T, 4, order::big>( tmp, v ); p[0] = tmp[2]; p[1] = tmp[3]; } }; // truncating store 4 -> 3 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 4, Order, 3, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 4 ]; boost::endian::endian_store<T, 4, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; p[2] = tmp[2]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 4, Order, 3, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 4 ]; boost::endian::endian_store<T, 4, order::big>( tmp, v ); p[0] = tmp[1]; p[1] = tmp[2]; p[2] = tmp[3]; } }; // truncating store 8 -> 1 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 1, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 1, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[7]; } }; // truncating store 8 -> 2 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 2, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 2, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[6]; p[1] = tmp[7]; } }; // truncating store 8 -> 3 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 3, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; p[2] = tmp[2]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 3, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[5]; p[1] = tmp[6]; p[2] = tmp[7]; } }; // truncating store 8 -> 4 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 4, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; p[2] = tmp[2]; p[3] = tmp[3]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 4, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[4]; p[1] = tmp[5]; p[2] = tmp[6]; p[3] = tmp[7]; } }; // truncating store 8 -> 5 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 5, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; p[2] = tmp[2]; p[3] = tmp[3]; p[4] = tmp[4]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 5, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[3]; p[1] = tmp[4]; p[2] = tmp[5]; p[3] = tmp[6]; p[4] = tmp[7]; } }; // truncating store 8 -> 6 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 6, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; p[2] = tmp[2]; p[3] = tmp[3]; p[4] = tmp[4]; p[5] = tmp[5]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 6, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[2]; p[1] = tmp[3]; p[2] = tmp[4]; p[3] = tmp[5]; p[4] = tmp[6]; p[5] = tmp[7]; } }; // truncating store 8 -> 7 template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 7, order::little> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::little>( tmp, v ); p[0] = tmp[0]; p[1] = tmp[1]; p[2] = tmp[2]; p[3] = tmp[3]; p[4] = tmp[4]; p[5] = tmp[5]; p[6] = tmp[6]; } }; template<class T, BOOST_SCOPED_ENUM(order) Order> struct endian_store_impl<T, 8, Order, 7, order::big> { inline void operator()( unsigned char * p, T const & v ) const BOOST_NOEXCEPT { BOOST_STATIC_ASSERT( is_integral<T>::value || is_enum<T>::value ); unsigned char tmp[ 8 ]; boost::endian::endian_store<T, 8, order::big>( tmp, v ); p[0] = tmp[1]; p[1] = tmp[2]; p[2] = tmp[3]; p[3] = tmp[4]; p[4] = tmp[5]; p[5] = tmp[6]; p[6] = tmp[7]; } }; } // namespace detail } // namespace endian } // namespace boost #endif // BOOST_ENDIAN_DETAIL_ENDIAN_STORE_HPP_INCLUDED