| // Boost endian.hpp header file (proposed) ----------------------------------// |
| |
| // (C) Copyright Darin Adler 2000 |
| // (C) Copyright Beman Dawes 2006 |
| |
| // 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/endian |
| |
| //----------------------------------------------------------------------------// |
| |
| // Original design developed by Darin Adler based on classes developed by Mark |
| // Borgerding. Four original class templates 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. |
| |
| #ifndef BOOST_ENDIAN_HPP |
| #define BOOST_ENDIAN_HPP |
| |
| #include <boost/detail/endian.hpp> |
| #include <boost/spirit/home/support/detail/integer/cover_operators.hpp> |
| #include <boost/type_traits/is_signed.hpp> |
| #include <boost/cstdint.hpp> |
| #include <boost/static_assert.hpp> |
| #include <iosfwd> |
| #include <climits> |
| |
| # if CHAR_BIT != 8 |
| # error Platforms with CHAR_BIT != 8 are not supported |
| # endif |
| |
| namespace boost |
| { |
| 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) |
| { return *(bytes - 1) | (next::load_big(bytes - 1) << 8); } |
| static T load_little(const unsigned char* bytes) |
| { return *bytes | (next::load_little(bytes + 1) << 8); } |
| |
| static void store_big(char* bytes, T value) |
| { |
| *(bytes - 1) = static_cast<char>(value); |
| next::store_big(bytes - 1, value >> 8); |
| } |
| static void store_little(char* bytes, T value) |
| { |
| *bytes = static_cast<char>(value); |
| next::store_little(bytes + 1, value >> 8); |
| } |
| }; |
| |
| template <typename T> |
| struct unrolled_byte_loops<T, 1, false> |
| { |
| static T load_big(const unsigned char* bytes) |
| { return *(bytes - 1); } |
| static T load_little(const unsigned char* bytes) |
| { return *bytes; } |
| static void store_big(char* bytes, T value) |
| { *(bytes - 1) = static_cast<char>(value); } |
| static void store_little(char* bytes, T value) |
| { *bytes = static_cast<char>(value); } |
| |
| }; |
| |
| template <typename T> |
| struct unrolled_byte_loops<T, 1, true> |
| { |
| static T load_big(const unsigned char* bytes) |
| { return *reinterpret_cast<const signed char*>(bytes - 1); } |
| static T load_little(const unsigned char* bytes) |
| { return *reinterpret_cast<const signed char*>(bytes); } |
| static void store_big(char* bytes, T value) |
| { *(bytes - 1) = static_cast<char>(value); } |
| static void store_little(char* bytes, T value) |
| { *bytes = static_cast<char>(value); } |
| }; |
| |
| template <typename T, std::size_t n_bytes> |
| inline |
| T load_big_endian(const void* bytes) |
| { |
| 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) |
| { |
| 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) |
| { |
| 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) |
| { |
| unrolled_byte_loops<T, n_bytes>::store_little |
| (static_cast<char*>(bytes), value); |
| } |
| |
| } // namespace detail |
| |
| namespace integer |
| { |
| |
| // endian class template and specializations -----------------------------// |
| |
| enum endianness { big, little, native }; |
| |
| enum alignment { unaligned, aligned }; |
| |
| template <endianness E, typename T, std::size_t n_bits, |
| alignment A = unaligned> |
| class endian; |
| |
| // 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. |
| |
| template <typename T, std::size_t n_bits> |
| class endian< big, T, n_bits, unaligned > |
| : cover_operators< endian< big, T, n_bits >, T > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| public: |
| typedef T value_type; |
| endian() {} |
| endian(T i) { detail::store_big_endian<T, n_bits/8>(bytes, i); } |
| operator T() const |
| { return detail::load_big_endian<T, n_bits/8>(bytes); } |
| private: |
| char bytes[n_bits/8]; |
| }; |
| |
| template <typename T, std::size_t n_bits> |
| class endian< little, T, n_bits, unaligned > |
| : cover_operators< endian< little, T, n_bits >, T > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| public: |
| typedef T value_type; |
| endian() {} |
| endian(T i) { detail::store_little_endian<T, n_bits/8>(bytes, i); } |
| operator T() const |
| { return detail::load_little_endian<T, n_bits/8>(bytes); } |
| private: |
| char bytes[n_bits/8]; |
| }; |
| |
| template <typename T, std::size_t n_bits> |
| class endian< native, T, n_bits, unaligned > |
| : cover_operators< endian< native, T, n_bits >, T > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| public: |
| typedef T value_type; |
| endian() {} |
| # ifdef BOOST_BIG_ENDIAN |
| endian(T i) { detail::store_big_endian<T, n_bits/8>(bytes, i); } |
| operator T() const |
| { return detail::load_big_endian<T, n_bits/8>(bytes); } |
| # else |
| endian(T i) { detail::store_little_endian<T, n_bits/8>(bytes, i); } |
| operator T() const |
| { return detail::load_little_endian<T, n_bits/8>(bytes); } |
| # endif |
| private: |
| char bytes[n_bits/8]; |
| }; |
| |
| // Specializations that mimic built-in integer types. |
| // These typically have the same alignment as the underlying types. |
| |
| template <typename T, std::size_t n_bits> |
| class endian< big, T, n_bits, aligned > |
| : cover_operators< endian< big, T, n_bits, aligned >, T > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| BOOST_STATIC_ASSERT( sizeof(T) == n_bits/8 ); |
| public: |
| typedef T value_type; |
| endian() {} |
| #ifdef BOOST_BIG_ENDIAN |
| endian(T i) : integer(i) { } |
| operator T() const { return integer; } |
| #else |
| endian(T i) { detail::store_big_endian<T, sizeof(T)>(&integer, i); } |
| operator T() const |
| { return detail::load_big_endian<T, sizeof(T)>(&integer); } |
| #endif |
| private: |
| T integer; |
| }; |
| |
| template <typename T, std::size_t n_bits> |
| class endian< little, T, n_bits, aligned > |
| : cover_operators< endian< little, T, n_bits, aligned >, T > |
| { |
| BOOST_STATIC_ASSERT( (n_bits/8)*8 == n_bits ); |
| BOOST_STATIC_ASSERT( sizeof(T) == n_bits/8 ); |
| public: |
| typedef T value_type; |
| endian() {} |
| #ifdef BOOST_LITTLE_ENDIAN |
| endian(T i) : integer(i) { } |
| operator T() const { return integer; } |
| #else |
| endian(T i) |
| { detail::store_little_endian<T, sizeof(T)>(&integer, i); } |
| operator T() const |
| { return detail::load_little_endian<T, sizeof(T)>(&integer); } |
| #endif |
| private: |
| T integer; |
| }; |
| |
| // naming convention typedefs --------------------------------------------// |
| |
| // unaligned big endian signed integer types |
| typedef endian< big, int_least8_t, 8 > big8_t; |
| typedef endian< big, int_least16_t, 16 > big16_t; |
| typedef endian< big, int_least32_t, 24 > big24_t; |
| typedef endian< big, int_least32_t, 32 > big32_t; |
| typedef endian< big, int_least64_t, 40 > big40_t; |
| typedef endian< big, int_least64_t, 48 > big48_t; |
| typedef endian< big, int_least64_t, 56 > big56_t; |
| typedef endian< big, int_least64_t, 64 > big64_t; |
| |
| // unaligned big endian unsigned integer types |
| typedef endian< big, uint_least8_t, 8 > ubig8_t; |
| typedef endian< big, uint_least16_t, 16 > ubig16_t; |
| typedef endian< big, uint_least32_t, 24 > ubig24_t; |
| typedef endian< big, uint_least32_t, 32 > ubig32_t; |
| typedef endian< big, uint_least64_t, 40 > ubig40_t; |
| typedef endian< big, uint_least64_t, 48 > ubig48_t; |
| typedef endian< big, uint_least64_t, 56 > ubig56_t; |
| typedef endian< big, uint_least64_t, 64 > ubig64_t; |
| |
| // unaligned little endian signed integer types |
| typedef endian< little, int_least8_t, 8 > little8_t; |
| typedef endian< little, int_least16_t, 16 > little16_t; |
| typedef endian< little, int_least32_t, 24 > little24_t; |
| typedef endian< little, int_least32_t, 32 > little32_t; |
| typedef endian< little, int_least64_t, 40 > little40_t; |
| typedef endian< little, int_least64_t, 48 > little48_t; |
| typedef endian< little, int_least64_t, 56 > little56_t; |
| typedef endian< little, int_least64_t, 64 > little64_t; |
| |
| // unaligned little endian unsigned integer types |
| typedef endian< little, uint_least8_t, 8 > ulittle8_t; |
| typedef endian< little, uint_least16_t, 16 > ulittle16_t; |
| typedef endian< little, uint_least32_t, 24 > ulittle24_t; |
| typedef endian< little, uint_least32_t, 32 > ulittle32_t; |
| typedef endian< little, uint_least64_t, 40 > ulittle40_t; |
| typedef endian< little, uint_least64_t, 48 > ulittle48_t; |
| typedef endian< little, uint_least64_t, 56 > ulittle56_t; |
| typedef endian< little, uint_least64_t, 64 > ulittle64_t; |
| |
| // unaligned native endian signed integer types |
| typedef endian< native, int_least8_t, 8 > native8_t; |
| typedef endian< native, int_least16_t, 16 > native16_t; |
| typedef endian< native, int_least32_t, 24 > native24_t; |
| typedef endian< native, int_least32_t, 32 > native32_t; |
| typedef endian< native, int_least64_t, 40 > native40_t; |
| typedef endian< native, int_least64_t, 48 > native48_t; |
| typedef endian< native, int_least64_t, 56 > native56_t; |
| typedef endian< native, int_least64_t, 64 > native64_t; |
| |
| // unaligned native endian unsigned integer types |
| typedef endian< native, uint_least8_t, 8 > unative8_t; |
| typedef endian< native, uint_least16_t, 16 > unative16_t; |
| typedef endian< native, uint_least32_t, 24 > unative24_t; |
| typedef endian< native, uint_least32_t, 32 > unative32_t; |
| typedef endian< native, uint_least64_t, 40 > unative40_t; |
| typedef endian< native, uint_least64_t, 48 > unative48_t; |
| typedef endian< native, uint_least64_t, 56 > unative56_t; |
| typedef endian< native, uint_least64_t, 64 > unative64_t; |
| |
| #define BOOST_HAS_INT16_T |
| #define BOOST_HAS_INT32_T |
| #define BOOST_HAS_INT64_T |
| |
| // These types only present if platform has exact size integers: |
| // aligned big endian signed integer types |
| // aligned big endian unsigned integer types |
| // aligned little endian signed integer types |
| // aligned little endian unsigned integer types |
| |
| // aligned native endian typedefs are not provided because |
| // <cstdint> types are superior for this use case |
| |
| # if defined(BOOST_HAS_INT16_T) |
| typedef endian< big, int16_t, 16, aligned > aligned_big16_t; |
| typedef endian< big, uint16_t, 16, aligned > aligned_ubig16_t; |
| typedef endian< little, int16_t, 16, aligned > aligned_little16_t; |
| typedef endian< little, uint16_t, 16, aligned > aligned_ulittle16_t; |
| # endif |
| |
| # if defined(BOOST_HAS_INT32_T) |
| typedef endian< big, int32_t, 32, aligned > aligned_big32_t; |
| typedef endian< big, uint32_t, 32, aligned > aligned_ubig32_t; |
| typedef endian< little, int32_t, 32, aligned > aligned_little32_t; |
| typedef endian< little, uint32_t, 32, aligned > aligned_ulittle32_t; |
| # endif |
| |
| # if defined(BOOST_HAS_INT64_T) |
| typedef endian< big, int64_t, 64, aligned > aligned_big64_t; |
| typedef endian< big, uint64_t, 64, aligned > aligned_ubig64_t; |
| typedef endian< little, int64_t, 64, aligned > aligned_little64_t; |
| typedef endian< little, uint64_t, 64, aligned > aligned_ulittle64_t; |
| # endif |
| |
| } // namespace integer |
| } // namespace boost |
| |
| #endif // BOOST_ENDIAN_HPP |