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Editing: buffers.hpp
// boost/endian/buffers.hpp ----------------------------------------------------------// // (C) Copyright Darin Adler 2000 // (C) Copyright Beman Dawes 2006, 2009, 2014 // (C) Copyright Peter Dimov 2019 // Distributed under the Boost Software License, Version 1.0. // See http://www.boost.org/LICENSE_1_0.txt // See library home page at http://www.boost.org/libs/endian //--------------------------------------------------------------------------------------// // Original design developed by Darin Adler based on classes developed by Mark // Borgerding. Four original class templates were combined into a single endian // class template by Beman Dawes, who also added the unrolled_byte_loops sign // partial specialization to correctly extend the sign when cover integer size // differs from endian representation size. // TODO: When a compiler supporting constexpr becomes available, try possible uses. #ifndef BOOST_ENDIAN_BUFFERS_HPP #define BOOST_ENDIAN_BUFFERS_HPP #if defined(_MSC_VER) # pragma warning(push) # pragma warning(disable: 4127) // conditional expression is constant #endif #include <boost/endian/detail/endian_store.hpp> #include <boost/endian/detail/endian_load.hpp> #include <boost/core/scoped_enum.hpp> #include <boost/static_assert.hpp> #include <boost/cstdint.hpp> #include <boost/config.hpp> #include <boost/config/workaround.hpp> #include <iosfwd> #include <climits> #include <cstring> #if defined(BOOST_BORLANDC) || defined(BOOST_CODEGEARC) # pragma pack(push, 1) #endif # if CHAR_BIT != 8 # error Platforms with CHAR_BIT != 8 are not supported # endif # ifdef BOOST_NO_CXX11_DEFAULTED_FUNCTIONS # define BOOST_ENDIAN_DEFAULT_CONSTRUCT {} // C++03 # else # define BOOST_ENDIAN_DEFAULT_CONSTRUCT = default; // C++0x # endif // g++ pre-4.6 does not support unrestricted unions, but we have no Config macro for that # if (defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) || BOOST_WORKAROUND(BOOST_GCC, < 40600)) && defined(BOOST_ENDIAN_FORCE_PODNESS) # define BOOST_ENDIAN_NO_CTORS # endif //---------------------------------- synopsis ----------------------------------------// namespace boost { namespace endian { BOOST_SCOPED_ENUM_START(align) {no, yes # ifdef BOOST_ENDIAN_DEPRECATED_NAMES , unaligned = no, aligned = yes # endif }; BOOST_SCOPED_ENUM_END template <BOOST_SCOPED_ENUM(order) Order, class T, std::size_t n_bits, BOOST_SCOPED_ENUM(align) A = align::no> class endian_buffer; // aligned big endian signed integer buffers typedef endian_buffer<order::big, int8_t, 8, align::yes> big_int8_buf_at; typedef endian_buffer<order::big, int16_t, 16, align::yes> big_int16_buf_at; typedef endian_buffer<order::big, int32_t, 32, align::yes> big_int32_buf_at; typedef endian_buffer<order::big, int64_t, 64, align::yes> big_int64_buf_at; // aligned big endian unsigned integer buffers typedef endian_buffer<order::big, uint8_t, 8, align::yes> big_uint8_buf_at; typedef endian_buffer<order::big, uint16_t, 16, align::yes> big_uint16_buf_at; typedef endian_buffer<order::big, uint32_t, 32, align::yes> big_uint32_buf_at; typedef endian_buffer<order::big, uint64_t, 64, align::yes> big_uint64_buf_at; // aligned little endian signed integer buffers typedef endian_buffer<order::little, int8_t, 8, align::yes> little_int8_buf_at; typedef endian_buffer<order::little, int16_t, 16, align::yes> little_int16_buf_at; typedef endian_buffer<order::little, int32_t, 32, align::yes> little_int32_buf_at; typedef endian_buffer<order::little, int64_t, 64, align::yes> little_int64_buf_at; // aligned little endian unsigned integer buffers typedef endian_buffer<order::little, uint8_t, 8, align::yes> little_uint8_buf_at; typedef endian_buffer<order::little, uint16_t, 16, align::yes> little_uint16_buf_at; typedef endian_buffer<order::little, uint32_t, 32, align::yes> little_uint32_buf_at; typedef endian_buffer<order::little, uint64_t, 64, align::yes> little_uint64_buf_at; // aligned floating point buffers typedef endian_buffer<order::big, float, 32, align::yes> big_float32_buf_at; typedef endian_buffer<order::big, double, 64, align::yes> big_float64_buf_at; typedef endian_buffer<order::little, float, 32, align::yes> little_float32_buf_at; typedef endian_buffer<order::little, double, 64, align::yes> little_float64_buf_at; // aligned native endian typedefs are not provided because // <cstdint> types are superior for this use case // unaligned big endian signed integer buffers typedef endian_buffer<order::big, int_least8_t, 8> big_int8_buf_t; typedef endian_buffer<order::big, int_least16_t, 16> big_int16_buf_t; typedef endian_buffer<order::big, int_least32_t, 24> big_int24_buf_t; typedef endian_buffer<order::big, int_least32_t, 32> big_int32_buf_t; typedef endian_buffer<order::big, int_least64_t, 40> big_int40_buf_t; typedef endian_buffer<order::big, int_least64_t, 48> big_int48_buf_t; typedef endian_buffer<order::big, int_least64_t, 56> big_int56_buf_t; typedef endian_buffer<order::big, int_least64_t, 64> big_int64_buf_t; // unaligned big endian unsigned integer buffers typedef endian_buffer<order::big, uint_least8_t, 8> big_uint8_buf_t; typedef endian_buffer<order::big, uint_least16_t, 16> big_uint16_buf_t; typedef endian_buffer<order::big, uint_least32_t, 24> big_uint24_buf_t; typedef endian_buffer<order::big, uint_least32_t, 32> big_uint32_buf_t; typedef endian_buffer<order::big, uint_least64_t, 40> big_uint40_buf_t; typedef endian_buffer<order::big, uint_least64_t, 48> big_uint48_buf_t; typedef endian_buffer<order::big, uint_least64_t, 56> big_uint56_buf_t; typedef endian_buffer<order::big, uint_least64_t, 64> big_uint64_buf_t; // unaligned little endian signed integer buffers typedef endian_buffer<order::little, int_least8_t, 8> little_int8_buf_t; typedef endian_buffer<order::little, int_least16_t, 16> little_int16_buf_t; typedef endian_buffer<order::little, int_least32_t, 24> little_int24_buf_t; typedef endian_buffer<order::little, int_least32_t, 32> little_int32_buf_t; typedef endian_buffer<order::little, int_least64_t, 40> little_int40_buf_t; typedef endian_buffer<order::little, int_least64_t, 48> little_int48_buf_t; typedef endian_buffer<order::little, int_least64_t, 56> little_int56_buf_t; typedef endian_buffer<order::little, int_least64_t, 64> little_int64_buf_t; // unaligned little endian unsigned integer buffers typedef endian_buffer<order::little, uint_least8_t, 8> little_uint8_buf_t; typedef endian_buffer<order::little, uint_least16_t, 16> little_uint16_buf_t; typedef endian_buffer<order::little, uint_least32_t, 24> little_uint24_buf_t; typedef endian_buffer<order::little, uint_least32_t, 32> little_uint32_buf_t; typedef endian_buffer<order::little, uint_least64_t, 40> little_uint40_buf_t; typedef endian_buffer<order::little, uint_least64_t, 48> little_uint48_buf_t; typedef endian_buffer<order::little, uint_least64_t, 56> little_uint56_buf_t; typedef endian_buffer<order::little, uint_least64_t, 64> little_uint64_buf_t; // unaligned native endian signed integer buffers typedef endian_buffer<order::native, int_least8_t, 8> native_int8_buf_t; typedef endian_buffer<order::native, int_least16_t, 16> native_int16_buf_t; typedef endian_buffer<order::native, int_least32_t, 24> native_int24_buf_t; typedef endian_buffer<order::native, int_least32_t, 32> native_int32_buf_t; typedef endian_buffer<order::native, int_least64_t, 40> native_int40_buf_t; typedef endian_buffer<order::native, int_least64_t, 48> native_int48_buf_t; typedef endian_buffer<order::native, int_least64_t, 56> native_int56_buf_t; typedef endian_buffer<order::native, int_least64_t, 64> native_int64_buf_t; // unaligned native endian unsigned integer buffers typedef endian_buffer<order::native, uint_least8_t, 8> native_uint8_buf_t; typedef endian_buffer<order::native, uint_least16_t, 16> native_uint16_buf_t; typedef endian_buffer<order::native, uint_least32_t, 24> native_uint24_buf_t; typedef endian_buffer<order::native, uint_least32_t, 32> native_uint32_buf_t; typedef endian_buffer<order::native, uint_least64_t, 40> native_uint40_buf_t; typedef endian_buffer<order::native, uint_least64_t, 48> native_uint48_buf_t; typedef endian_buffer<order::native, uint_least64_t, 56> native_uint56_buf_t; typedef endian_buffer<order::native, uint_least64_t, 64> native_uint64_buf_t; // unaligned floating point buffers typedef endian_buffer<order::big, float, 32, align::no> big_float32_buf_t; typedef endian_buffer<order::big, double, 64, align::no> big_float64_buf_t; typedef endian_buffer<order::little, float, 32, align::no> little_float32_buf_t; typedef endian_buffer<order::little, double, 64, align::no> little_float64_buf_t; typedef endian_buffer<order::native, float, 32, align::no> native_float32_buf_t; typedef endian_buffer<order::native, double, 64, align::no> native_float64_buf_t; // Stream inserter template <class charT, class traits, BOOST_SCOPED_ENUM(order) Order, class T, std::size_t n_bits, BOOST_SCOPED_ENUM(align) A> std::basic_ostream<charT, traits>& operator<<(std::basic_ostream<charT, traits>& os, const endian_buffer<Order, T, n_bits, A>& x) { return os << x.value(); } // Stream extractor template <class charT, class traits, BOOST_SCOPED_ENUM(order) Order, class T, std::size_t n_bits, BOOST_SCOPED_ENUM(align) A> std::basic_istream<charT, traits>& operator>>(std::basic_istream<charT, traits>& is, endian_buffer<Order, T, n_bits, A>& x) { T i; if (is >> i) x = i; return is; } //---------------------------------- end synopsis ------------------------------------// // endian_buffer class template specializations --------------------------------------// // Specializations that represent unaligned bytes. // Taking an integer type as a parameter provides a nice way to pass both // the size and signedness of the desired integer and get the appropriate // corresponding integer type for the interface. // Q: Should endian_buffer supply "value_type operator value_type() const noexcept"? // A: No. The rationale for endian_buffers is to prevent high-cost hidden // conversions. If an implicit conversion operator is supplied, hidden conversions // can occur. // unaligned endian_buffer specialization template< BOOST_SCOPED_ENUM(order) Order, class T, std::size_t n_bits > class endian_buffer<Order, T, n_bits, align::no> { private: BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); unsigned char value_[ n_bits / 8 ]; public: typedef T value_type; #ifndef BOOST_ENDIAN_NO_CTORS endian_buffer() BOOST_ENDIAN_DEFAULT_CONSTRUCT explicit endian_buffer( T val ) BOOST_NOEXCEPT { boost::endian::endian_store<T, n_bits / 8, Order>( value_, val ); } #endif endian_buffer& operator=( T val ) BOOST_NOEXCEPT { boost::endian::endian_store<T, n_bits / 8, Order>( value_, val ); return *this; } value_type value() const BOOST_NOEXCEPT { return boost::endian::endian_load<T, n_bits / 8, Order>( value_ ); } unsigned char const * data() const BOOST_NOEXCEPT { return value_; } unsigned char * data() BOOST_NOEXCEPT { return value_; } }; // aligned specializations; only n_bits == 16/32/64 supported // aligned endian_buffer specialization template< BOOST_SCOPED_ENUM(order) Order, class T, std::size_t n_bits > class endian_buffer<Order, T, n_bits, align::yes> { private: BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); BOOST_STATIC_ASSERT( sizeof(T) == n_bits/8 ); union { unsigned char value_[ n_bits / 8 ]; T align_; }; public: typedef T value_type; #ifndef BOOST_ENDIAN_NO_CTORS endian_buffer() BOOST_ENDIAN_DEFAULT_CONSTRUCT explicit endian_buffer( T val ) BOOST_NOEXCEPT { boost::endian::endian_store<T, n_bits / 8, Order>( value_, val ); } #endif endian_buffer& operator=( T val ) BOOST_NOEXCEPT { boost::endian::endian_store<T, n_bits / 8, Order>( value_, val ); return *this; } value_type value() const BOOST_NOEXCEPT { return boost::endian::endian_load<T, n_bits / 8, Order>( value_ ); } unsigned char const * data() const BOOST_NOEXCEPT { return value_; } unsigned char * data() BOOST_NOEXCEPT { return value_; } }; // aligned native endian_buffer specialization template< class T, std::size_t n_bits > class endian_buffer<order::native, T, n_bits, align::yes> { private: BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); BOOST_STATIC_ASSERT( sizeof(T) == n_bits/8 ); T value_; public: typedef T value_type; #ifndef BOOST_ENDIAN_NO_CTORS endian_buffer() BOOST_ENDIAN_DEFAULT_CONSTRUCT explicit endian_buffer( T val ) BOOST_NOEXCEPT: value_( val ) { } #endif endian_buffer& operator=( T val ) BOOST_NOEXCEPT { value_ = val; return *this; } value_type value() const BOOST_NOEXCEPT { return value_; } unsigned char const * data() const BOOST_NOEXCEPT { return reinterpret_cast< unsigned char const* >( &value_ ); } unsigned char * data() BOOST_NOEXCEPT { return reinterpret_cast< unsigned char* >( &value_ ); } }; } // namespace endian } // namespace boost #if defined(BOOST_BORLANDC) || defined(BOOST_CODEGEARC) # pragma pack(pop) #endif #if defined(_MSC_VER) # pragma warning(pop) #endif #endif // BOOST_ENDIAN_BUFFERS_HPP
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