ecency-mobile/ios/Pods/boost-for-react-native/boost/endian/buffers.hpp

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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