libcruft-util/endian.hpp
Danny Robson fba15db34b endian: complete reimplementation
Old implementation was overly verbose. We can just rely on gcc builtins as
we can't actually build on anything else anyway.
2014-07-15 19:44:39 +10:00

68 lines
2.2 KiB
C++

/*
* This file is part of libgim.
*
* libgim is free software: you can redistribute it and/or modify it under the
* terms of the GNU General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later
* version.
*
* libgim is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2010-2014 Danny Robson <danny@nerdcruft.net>
*/
#ifndef __UTIL_ENDIAN_HPP
#define __UTIL_ENDIAN_HPP
#include <cstdint>
//-----------------------------------------------------------------------------
template <typename T>
constexpr T
bswap (T);
template <> constexpr uint8_t bswap ( uint8_t v) { return v; }
template <> constexpr uint16_t bswap (uint16_t v) { return __builtin_bswap16 (v); }
template <> constexpr uint32_t bswap (uint32_t v) { return __builtin_bswap32 (v); }
template <> constexpr uint64_t bswap (uint64_t v) { return __builtin_bswap64 (v); }
//-----------------------------------------------------------------------------
template <typename T>
constexpr T
identity (T &&v) {
return v;
}
//-----------------------------------------------------------------------------
#if defined(WORDS_BIGENDIAN)
template <typename T> constexpr T hton (T v) { return v; }
template <typename T> constexpr T ntoh (T v) { return v; }
template <typename T> constexpr T htob (T v) { return v; }
template <typename T> constexpr T htol (T v) { return bswap (v); }
template <typename T> constexpr T btoh (T v) { return v; }
template <typename T> constexpr T ltoh (T v) { return bswap (v); }
#else
template <typename T> constexpr T hton (T v) { return bswap (v); }
template <typename T> constexpr T ntoh (T v) { return bswap (v); }
template <typename T> constexpr T htob (T v) { return bswap (v); }
template <typename T> constexpr T htol (T v) { return v; }
template <typename T> constexpr T btoh (T v) { return bswap (v); }
template <typename T> constexpr T ltoh (T v) { return v; }
#endif
#endif