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+// 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