| // boost/endian/buffers.hpp ----------------------------------------------------------// |
| |
| // (C) Copyright Darin Adler 2000 |
| // (C) Copyright Beman Dawes 2006, 2009, 2014 |
| |
| // 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:4365) // conversion ... signed/unsigned mismatch |
| #endif |
| |
| #ifdef BOOST_ENDIAN_LOG |
| # include <iostream> |
| #endif |
| |
| #if defined(__BORLANDC__) || defined( __CODEGEARC__) |
| # pragma pack(push, 1) |
| #endif |
| |
| #include <boost/config.hpp> |
| #include <boost/predef/detail/endian_compat.h> |
| #include <boost/endian/conversion.hpp> |
| #include <boost/type_traits/is_signed.hpp> |
| #include <boost/cstdint.hpp> |
| #include <boost/static_assert.hpp> |
| #include <boost/core/scoped_enum.hpp> |
| #include <iosfwd> |
| #include <climits> |
| |
| # 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 |
| |
| # if defined(BOOST_NO_CXX11_DEFAULTED_FUNCTIONS) && 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 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; |
| |
| # ifdef BOOST_BIG_ENDIAN |
| // unaligned native endian signed integer buffers |
| typedef big_int8_buf_t native_int8_buf_t; |
| typedef big_int16_buf_t native_int16_buf_t; |
| typedef big_int24_buf_t native_int24_buf_t; |
| typedef big_int32_buf_t native_int32_buf_t; |
| typedef big_int40_buf_t native_int40_buf_t; |
| typedef big_int48_buf_t native_int48_buf_t; |
| typedef big_int56_buf_t native_int56_buf_t; |
| typedef big_int64_buf_t native_int64_buf_t; |
| |
| // unaligned native endian unsigned integer buffers |
| typedef big_uint8_buf_t native_uint8_buf_t; |
| typedef big_uint16_buf_t native_uint16_buf_t; |
| typedef big_uint24_buf_t native_uint24_buf_t; |
| typedef big_uint32_buf_t native_uint32_buf_t; |
| typedef big_uint40_buf_t native_uint40_buf_t; |
| typedef big_uint48_buf_t native_uint48_buf_t; |
| typedef big_uint56_buf_t native_uint56_buf_t; |
| typedef big_uint64_buf_t native_uint64_buf_t; |
| # else |
| // unaligned native endian signed integer buffers |
| typedef little_int8_buf_t native_int8_buf_t; |
| typedef little_int16_buf_t native_int16_buf_t; |
| typedef little_int24_buf_t native_int24_buf_t; |
| typedef little_int32_buf_t native_int32_buf_t; |
| typedef little_int40_buf_t native_int40_buf_t; |
| typedef little_int48_buf_t native_int48_buf_t; |
| typedef little_int56_buf_t native_int56_buf_t; |
| typedef little_int64_buf_t native_int64_buf_t; |
| |
| // unaligned native endian unsigned integer buffers |
| typedef little_uint8_buf_t native_uint8_buf_t; |
| typedef little_uint16_buf_t native_uint16_buf_t; |
| typedef little_uint24_buf_t native_uint24_buf_t; |
| typedef little_uint32_buf_t native_uint32_buf_t; |
| typedef little_uint40_buf_t native_uint40_buf_t; |
| typedef little_uint48_buf_t native_uint48_buf_t; |
| typedef little_uint56_buf_t native_uint56_buf_t; |
| typedef little_uint64_buf_t native_uint64_buf_t; |
| # endif |
| |
| // 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 ------------------------------------// |
| |
| namespace detail |
| { |
| |
| // Unrolled loops for loading and storing streams of bytes. |
| |
| template <typename T, std::size_t n_bytes, |
| bool sign=boost::is_signed<T>::value > |
| struct unrolled_byte_loops |
| { |
| typedef unrolled_byte_loops<T, n_bytes - 1, sign> next; |
| |
| static T load_big(const unsigned char* bytes) BOOST_NOEXCEPT |
| { return static_cast<T>(*(bytes - 1) | (next::load_big(bytes - 1) << 8)); } |
| static T load_little(const unsigned char* bytes) BOOST_NOEXCEPT |
| { return static_cast<T>(*bytes | (next::load_little(bytes + 1) << 8)); } |
| |
| static void store_big(char* bytes, T value) BOOST_NOEXCEPT |
| { |
| *(bytes - 1) = static_cast<char>(value); |
| next::store_big(bytes - 1, static_cast<T>(value >> 8)); |
| } |
| static void store_little(char* bytes, T value) BOOST_NOEXCEPT |
| { |
| *bytes = static_cast<char>(value); |
| next::store_little(bytes + 1, static_cast<T>(value >> 8)); |
| } |
| }; |
| |
| template <typename T> |
| struct unrolled_byte_loops<T, 1, false> |
| { |
| static T load_big(const unsigned char* bytes) BOOST_NOEXCEPT |
| { return *(bytes - 1); } |
| static T load_little(const unsigned char* bytes) BOOST_NOEXCEPT |
| { return *bytes; } |
| static void store_big(char* bytes, T value) BOOST_NOEXCEPT |
| { *(bytes - 1) = static_cast<char>(value); } |
| static void store_little(char* bytes, T value) BOOST_NOEXCEPT |
| { *bytes = static_cast<char>(value); } |
| |
| }; |
| |
| template <typename T> |
| struct unrolled_byte_loops<T, 1, true> |
| { |
| static T load_big(const unsigned char* bytes) BOOST_NOEXCEPT |
| { return *reinterpret_cast<const signed char*>(bytes - 1); } |
| static T load_little(const unsigned char* bytes) BOOST_NOEXCEPT |
| { return *reinterpret_cast<const signed char*>(bytes); } |
| static void store_big(char* bytes, T value) BOOST_NOEXCEPT |
| { *(bytes - 1) = static_cast<char>(value); } |
| static void store_little(char* bytes, T value) BOOST_NOEXCEPT |
| { *bytes = static_cast<char>(value); } |
| }; |
| |
| template <typename T, std::size_t n_bytes> |
| inline |
| T load_big_endian(const void* bytes) BOOST_NOEXCEPT |
| { |
| return unrolled_byte_loops<T, n_bytes>::load_big |
| (static_cast<const unsigned char*>(bytes) + n_bytes); |
| } |
| |
| template <typename T, std::size_t n_bytes> |
| inline |
| T load_little_endian(const void* bytes) BOOST_NOEXCEPT |
| { |
| # if defined(__x86_64__) || defined(_M_X64) || defined(__i386) || defined(_M_IX86) |
| // On x86 (which is little endian), unaligned loads are permitted |
| if (sizeof(T) == n_bytes) // GCC 4.9, VC++ 14.0, and probably others, elide this |
| // test and generate code only for the applicable return |
| // case since sizeof(T) and n_bytes are known at compile |
| // time. |
| { |
| return *reinterpret_cast<T const *>(bytes); |
| } |
| # endif |
| return unrolled_byte_loops<T, n_bytes>::load_little |
| (static_cast<const unsigned char*>(bytes)); |
| } |
| |
| template <typename T, std::size_t n_bytes> |
| inline |
| void store_big_endian(void* bytes, T value) BOOST_NOEXCEPT |
| { |
| unrolled_byte_loops<T, n_bytes>::store_big |
| (static_cast<char*>(bytes) + n_bytes, value); |
| } |
| |
| template <typename T, std::size_t n_bytes> |
| inline |
| void store_little_endian(void* bytes, T value) BOOST_NOEXCEPT |
| { |
| # if defined(__x86_64__) || defined(_M_X64) || defined(__i386) || defined(_M_IX86) |
| // On x86 (which is little endian), unaligned stores are permitted |
| if (sizeof(T) == n_bytes) // GCC 4.9, VC++ 14.0, and probably others, elide this |
| // test and generate code only for the applicable return |
| // case since sizeof(T) and n_bytes are known at compile |
| // time. |
| { |
| *reinterpret_cast<T *>(bytes) = value; |
| return; |
| } |
| # endif |
| unrolled_byte_loops<T, n_bytes>::store_little |
| (static_cast<char*>(bytes), value); |
| } |
| |
| } // namespace detail |
| |
| # ifdef BOOST_ENDIAN_LOG |
| bool endian_log(true); |
| # endif |
| |
| // 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 big endian_buffer specialization |
| template <typename T, std::size_t n_bits> |
| class endian_buffer< order::big, T, n_bits, align::no > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| public: |
| typedef T value_type; |
| # ifndef BOOST_ENDIAN_NO_CTORS |
| endian_buffer() BOOST_ENDIAN_DEFAULT_CONSTRUCT |
| explicit endian_buffer(T val) BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "big, unaligned, " |
| << n_bits << "-bits, construct(" << val << ")\n"; |
| # endif |
| detail::store_big_endian<T, n_bits/8>(m_value, val); |
| } |
| # endif |
| endian_buffer & operator=(T val) BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if (endian_log) |
| std::cout << "big, unaligned, " << n_bits << "-bits, assign(" << val << ")\n"; |
| # endif |
| detail::store_big_endian<T, n_bits/8>(m_value, val); |
| return *this; |
| } |
| value_type value() const BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "big, unaligned, " << n_bits << "-bits, convert(" |
| << detail::load_big_endian<T, n_bits/8>(m_value) << ")\n"; |
| # endif |
| return detail::load_big_endian<T, n_bits/8>(m_value); |
| } |
| const char* data() const BOOST_NOEXCEPT { return m_value; } |
| protected: |
| char m_value[n_bits/8]; |
| }; |
| |
| // unaligned little endian_buffer specialization |
| template <typename T, std::size_t n_bits> |
| class endian_buffer< order::little, T, n_bits, align::no > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| public: |
| typedef T value_type; |
| # ifndef BOOST_ENDIAN_NO_CTORS |
| endian_buffer() BOOST_ENDIAN_DEFAULT_CONSTRUCT |
| explicit endian_buffer(T val) BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "little, unaligned, " << n_bits << "-bits, construct(" |
| << val << ")\n"; |
| # endif |
| detail::store_little_endian<T, n_bits/8>(m_value, val); |
| } |
| # endif |
| endian_buffer & operator=(T val) BOOST_NOEXCEPT |
| { detail::store_little_endian<T, n_bits/8>(m_value, val); return *this; } |
| value_type value() const BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "little, unaligned, " << n_bits << "-bits, convert(" |
| << detail::load_little_endian<T, n_bits/8>(m_value) << ")\n"; |
| # endif |
| return detail::load_little_endian<T, n_bits/8>(m_value); |
| } |
| const char* data() const BOOST_NOEXCEPT { return m_value; } |
| protected: |
| char m_value[n_bits/8]; |
| }; |
| |
| // align::yes specializations; only n_bits == 16/32/64 supported |
| |
| // aligned big endian_buffer specialization |
| template <typename T, std::size_t n_bits> |
| class endian_buffer<order::big, T, n_bits, align::yes> |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| BOOST_STATIC_ASSERT( sizeof(T) == 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 |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "big, aligned, " << n_bits |
| << "-bits, construct(" << val << ")\n"; |
| # endif |
| m_value = ::boost::endian::native_to_big(val); |
| } |
| |
| # endif |
| endian_buffer& operator=(T val) BOOST_NOEXCEPT |
| { |
| m_value = ::boost::endian::native_to_big(val); |
| return *this; |
| } |
| //operator value_type() const BOOST_NOEXCEPT |
| //{ |
| // return ::boost::endian::big_to_native(m_value); |
| //} |
| value_type value() const BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "big, aligned, " << n_bits << "-bits, convert(" |
| << ::boost::endian::big_to_native(m_value) << ")\n"; |
| # endif |
| return ::boost::endian::big_to_native(m_value); |
| } |
| const char* data() const BOOST_NOEXCEPT |
| {return reinterpret_cast<const char*>(&m_value);} |
| protected: |
| T m_value; |
| }; |
| |
| // aligned little endian_buffer specialization |
| template <typename T, std::size_t n_bits> |
| class endian_buffer<order::little, T, n_bits, align::yes> |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| BOOST_STATIC_ASSERT( sizeof(T) == 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 |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "little, aligned, " << n_bits |
| << "-bits, construct(" << val << ")\n"; |
| # endif |
| m_value = ::boost::endian::native_to_little(val); |
| } |
| |
| # endif |
| endian_buffer& operator=(T val) BOOST_NOEXCEPT |
| { |
| m_value = ::boost::endian::native_to_little(val); |
| return *this; |
| } |
| value_type value() const BOOST_NOEXCEPT |
| { |
| # ifdef BOOST_ENDIAN_LOG |
| if ( endian_log ) |
| std::cout << "little, aligned, " << n_bits << "-bits, convert(" |
| << ::boost::endian::little_to_native(m_value) << ")\n"; |
| # endif |
| return ::boost::endian::little_to_native(m_value); |
| } |
| const char* data() const BOOST_NOEXCEPT |
| {return reinterpret_cast<const char*>(&m_value);} |
| protected: |
| T m_value; |
| }; |
| |
| } // namespace endian |
| } // namespace boost |
| |
| #if defined(__BORLANDC__) || defined( __CODEGEARC__) |
| # pragma pack(pop) |
| #endif |
| |
| #if defined(_MSC_VER) |
| # pragma warning(pop) |
| #endif |
| |
| #endif // BOOST_ENDIAN_BUFFERS_HPP |
