byteswap.hpp
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#ifndef PROTOZERO_BYTESWAP_HPP
#define PROTOZERO_BYTESWAP_HPP
/*****************************************************************************
protozero - Minimalistic protocol buffer decoder and encoder in C++.
This file is from https://github.com/mapbox/protozero where you can find more
documentation.
*****************************************************************************/
#include <cassert>
#include <cstdint>
#include <protozero/config.hpp>
namespace protozero {
namespace detail {
inline uint32_t byteswap_impl(uint32_t value) noexcept {
#ifdef PROTOZERO_USE_BUILTIN_BSWAP
return __builtin_bswap32(value);
#else
return ((value & 0xff000000) >> 24) |
((value & 0x00ff0000) >> 8) |
((value & 0x0000ff00) << 8) |
((value & 0x000000ff) << 24);
#endif
}
inline uint64_t byteswap_impl(uint64_t value) noexcept {
#ifdef PROTOZERO_USE_BUILTIN_BSWAP
return __builtin_bswap64(value);
#else
return ((value & 0xff00000000000000ULL) >> 56) |
((value & 0x00ff000000000000ULL) >> 40) |
((value & 0x0000ff0000000000ULL) >> 24) |
((value & 0x000000ff00000000ULL) >> 8) |
((value & 0x00000000ff000000ULL) << 8) |
((value & 0x0000000000ff0000ULL) << 24) |
((value & 0x000000000000ff00ULL) << 40) |
((value & 0x00000000000000ffULL) << 56);
#endif
}
inline void byteswap_inplace(uint32_t* ptr) noexcept {
*ptr = byteswap_impl(*ptr);
}
inline void byteswap_inplace(uint64_t* ptr) noexcept {
*ptr = byteswap_impl(*ptr);
}
inline void byteswap_inplace(int32_t* ptr) noexcept {
auto bptr = reinterpret_cast<uint32_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
inline void byteswap_inplace(int64_t* ptr) noexcept {
auto bptr = reinterpret_cast<uint64_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
inline void byteswap_inplace(float* ptr) noexcept {
auto bptr = reinterpret_cast<uint32_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
inline void byteswap_inplace(double* ptr) noexcept {
auto bptr = reinterpret_cast<uint64_t*>(ptr);
*bptr = byteswap_impl(*bptr);
}
} // end namespace detail
} // end namespace protozero
#endif // PROTOZERO_BYTESWAP_HPP
config.hpp
Contains macro checks for different configurations.
protozero
All parts of the protozero header-only library are in this namespace.
Definition: byteswap.hpp:24