mirror of
https://github.com/microsoft/GSL.git
synced 2024-11-03 17:56:43 -05:00
ca3bf7710f
Intel C++ Compiler defines the `_MSC_VER` macro, but it doesn't support `[[gsl::*]]` attributes.
210 lines
6.5 KiB
Plaintext
210 lines
6.5 KiB
Plaintext
///////////////////////////////////////////////////////////////////////////////
|
|
//
|
|
// Copyright (c) 2015 Microsoft Corporation. All rights reserved.
|
|
//
|
|
// This code is licensed under the MIT License (MIT).
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
// THE SOFTWARE.
|
|
//
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
#ifndef GSL_BYTE_H
|
|
#define GSL_BYTE_H
|
|
|
|
//
|
|
// make suppress attributes work for some compilers
|
|
// Hopefully temporary until suppression standardization occurs
|
|
//
|
|
#if defined(__clang__)
|
|
#define GSL_SUPPRESS(x) [[gsl::suppress("x")]]
|
|
#else
|
|
#if defined(_MSC_VER) && ! defined(__INTEL_COMPILER)
|
|
#define GSL_SUPPRESS(x) [[gsl::suppress(x)]]
|
|
#else
|
|
#define GSL_SUPPRESS(x)
|
|
#endif // _MSC_VER
|
|
#endif // __clang__
|
|
|
|
#include <type_traits>
|
|
|
|
// VS2017 15.8 added support for the __cpp_lib_byte definition
|
|
// To do: drop _HAS_STD_BYTE when support for pre 15.8 expires
|
|
#ifdef _MSC_VER
|
|
|
|
#pragma warning(push)
|
|
|
|
// Turn MSVC /analyze rules that generate too much noise. TODO: fix in the tool.
|
|
#pragma warning(disable : 26493) // don't use c-style casts // TODO: MSVC suppression in templates does not always work
|
|
|
|
#ifndef GSL_USE_STD_BYTE
|
|
// this tests if we are under MSVC and the standard lib has std::byte and it is enabled
|
|
#if (defined(_HAS_STD_BYTE) && _HAS_STD_BYTE) || (defined(__cpp_lib_byte) && __cpp_lib_byte >= 201603)
|
|
|
|
#define GSL_USE_STD_BYTE 1
|
|
|
|
#else // (defined(_HAS_STD_BYTE) && _HAS_STD_BYTE) || (defined(__cpp_lib_byte) && __cpp_lib_byte >= 201603)
|
|
|
|
#define GSL_USE_STD_BYTE 0
|
|
|
|
#endif // (defined(_HAS_STD_BYTE) && _HAS_STD_BYTE) || (defined(__cpp_lib_byte) && __cpp_lib_byte >= 201603)
|
|
#endif // GSL_USE_STD_BYTE
|
|
|
|
#else // _MSC_VER
|
|
|
|
#ifndef GSL_USE_STD_BYTE
|
|
#include <cstddef> /* __cpp_lib_byte */
|
|
// this tests if we are under GCC or Clang with enough -std:c++1z power to get us std::byte
|
|
// also check if libc++ version is sufficient (> 5.0) or libstc++ actually contains std::byte
|
|
#if defined(__cplusplus) && (__cplusplus >= 201703L) && \
|
|
(defined(__cpp_lib_byte) && (__cpp_lib_byte >= 201603) || \
|
|
defined(_LIBCPP_VERSION) && (_LIBCPP_VERSION >= 5000))
|
|
|
|
#define GSL_USE_STD_BYTE 1
|
|
|
|
#else // defined(__cplusplus) && (__cplusplus >= 201703L) &&
|
|
// (defined(__cpp_lib_byte) && (__cpp_lib_byte >= 201603) ||
|
|
// defined(_LIBCPP_VERSION) && (_LIBCPP_VERSION >= 5000))
|
|
|
|
#define GSL_USE_STD_BYTE 0
|
|
|
|
#endif //defined(__cplusplus) && (__cplusplus >= 201703L) &&
|
|
// (defined(__cpp_lib_byte) && (__cpp_lib_byte >= 201603) ||
|
|
// defined(_LIBCPP_VERSION) && (_LIBCPP_VERSION >= 5000))
|
|
#endif // GSL_USE_STD_BYTE
|
|
|
|
#endif // _MSC_VER
|
|
|
|
// Use __may_alias__ attribute on gcc and clang
|
|
#if defined __clang__ || (defined(__GNUC__) && __GNUC__ > 5)
|
|
#define byte_may_alias __attribute__((__may_alias__))
|
|
#else // defined __clang__ || defined __GNUC__
|
|
#define byte_may_alias
|
|
#endif // defined __clang__ || defined __GNUC__
|
|
|
|
#if GSL_USE_STD_BYTE
|
|
#include <cstddef>
|
|
#endif
|
|
|
|
namespace gsl
|
|
{
|
|
#if GSL_USE_STD_BYTE
|
|
|
|
using std::byte;
|
|
using std::to_integer;
|
|
|
|
#else // GSL_USE_STD_BYTE
|
|
|
|
// This is a simple definition for now that allows
|
|
// use of byte within span<> to be standards-compliant
|
|
enum class byte_may_alias byte : unsigned char
|
|
{
|
|
};
|
|
|
|
template <class IntegerType, class = std::enable_if_t<std::is_integral<IntegerType>::value>>
|
|
constexpr byte& operator<<=(byte& b, IntegerType shift) noexcept
|
|
{
|
|
return b = byte(static_cast<unsigned char>(b) << shift);
|
|
}
|
|
|
|
template <class IntegerType, class = std::enable_if_t<std::is_integral<IntegerType>::value>>
|
|
constexpr byte operator<<(byte b, IntegerType shift) noexcept
|
|
{
|
|
return byte(static_cast<unsigned char>(b) << shift);
|
|
}
|
|
|
|
template <class IntegerType, class = std::enable_if_t<std::is_integral<IntegerType>::value>>
|
|
constexpr byte& operator>>=(byte& b, IntegerType shift) noexcept
|
|
{
|
|
return b = byte(static_cast<unsigned char>(b) >> shift);
|
|
}
|
|
|
|
template <class IntegerType, class = std::enable_if_t<std::is_integral<IntegerType>::value>>
|
|
constexpr byte operator>>(byte b, IntegerType shift) noexcept
|
|
{
|
|
return byte(static_cast<unsigned char>(b) >> shift);
|
|
}
|
|
|
|
constexpr byte& operator|=(byte& l, byte r) noexcept
|
|
{
|
|
return l = byte(static_cast<unsigned char>(l) | static_cast<unsigned char>(r));
|
|
}
|
|
|
|
constexpr byte operator|(byte l, byte r) noexcept
|
|
{
|
|
return byte(static_cast<unsigned char>(l) | static_cast<unsigned char>(r));
|
|
}
|
|
|
|
constexpr byte& operator&=(byte& l, byte r) noexcept
|
|
{
|
|
return l = byte(static_cast<unsigned char>(l) & static_cast<unsigned char>(r));
|
|
}
|
|
|
|
constexpr byte operator&(byte l, byte r) noexcept
|
|
{
|
|
return byte(static_cast<unsigned char>(l) & static_cast<unsigned char>(r));
|
|
}
|
|
|
|
constexpr byte& operator^=(byte& l, byte r) noexcept
|
|
{
|
|
return l = byte(static_cast<unsigned char>(l) ^ static_cast<unsigned char>(r));
|
|
}
|
|
|
|
constexpr byte operator^(byte l, byte r) noexcept
|
|
{
|
|
return byte(static_cast<unsigned char>(l) ^ static_cast<unsigned char>(r));
|
|
}
|
|
|
|
constexpr byte operator~(byte b) noexcept { return byte(~static_cast<unsigned char>(b)); }
|
|
|
|
template <class IntegerType, class = std::enable_if_t<std::is_integral<IntegerType>::value>>
|
|
constexpr IntegerType to_integer(byte b) noexcept
|
|
{
|
|
return static_cast<IntegerType>(b);
|
|
}
|
|
|
|
#endif // GSL_USE_STD_BYTE
|
|
|
|
template <bool E, typename T>
|
|
constexpr byte to_byte_impl(T t) noexcept
|
|
{
|
|
static_assert(
|
|
E, "gsl::to_byte(t) must be provided an unsigned char, otherwise data loss may occur. "
|
|
"If you are calling to_byte with an integer contant use: gsl::to_byte<t>() version.");
|
|
return static_cast<byte>(t);
|
|
}
|
|
template <>
|
|
// NOTE: need suppression since c++14 does not allow "return {t}"
|
|
// GSL_SUPPRESS(type.4) // NO-FORMAT: attribute // TODO: suppression does not work
|
|
constexpr byte to_byte_impl<true, unsigned char>(unsigned char t) noexcept
|
|
{
|
|
return byte(t);
|
|
}
|
|
|
|
template <typename T>
|
|
constexpr byte to_byte(T t) noexcept
|
|
{
|
|
return to_byte_impl<std::is_same<T, unsigned char>::value, T>(t);
|
|
}
|
|
|
|
template <int I>
|
|
constexpr byte to_byte() noexcept
|
|
{
|
|
static_assert(I >= 0 && I <= 255,
|
|
"gsl::byte only has 8 bits of storage, values must be in range 0-255");
|
|
return static_cast<byte>(I);
|
|
}
|
|
|
|
} // namespace gsl
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma warning(pop)
|
|
#endif // _MSC_VER
|
|
|
|
#endif // GSL_BYTE_H
|