/* Macros and inline functions to swap the order of bytes in integer values. Copyright (C) 1997-2020 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ #if !defined _BYTESWAP_H && !defined _NETINET_IN_H && !defined _ENDIAN_H # error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead." #endif #ifndef _BITS_BYTESWAP_H #define _BITS_BYTESWAP_H 1 #include <features.h> #include <bits/types.h> /* Swap bytes in 16-bit value. */ #define __bswap_constant_16(x) \ ((__uint16_t) ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8))) static __inline __uint16_t __bswap_16 (__uint16_t __bsx) { #if __GNUC_PREREQ (4, 8) return __builtin_bswap16 (__bsx); #else return __bswap_constant_16 (__bsx); #endif } /* Swap bytes in 32-bit value. */ #define __bswap_constant_32(x) \ ((((x) & 0xff000000u) >> 24) | (((x) & 0x00ff0000u) >> 8) \ | (((x) & 0x0000ff00u) << 8) | (((x) & 0x000000ffu) << 24)) static __inline __uint32_t __bswap_32 (__uint32_t __bsx) { #if __GNUC_PREREQ (4, 3) return __builtin_bswap32 (__bsx); #else return __bswap_constant_32 (__bsx); #endif } /* Swap bytes in 64-bit value. */ #define __bswap_constant_64(x) \ ((((x) & 0xff00000000000000ull) >> 56) \ | (((x) & 0x00ff000000000000ull) >> 40) \ | (((x) & 0x0000ff0000000000ull) >> 24) \ | (((x) & 0x000000ff00000000ull) >> 8) \ | (((x) & 0x00000000ff000000ull) << 8) \ | (((x) & 0x0000000000ff0000ull) << 24) \ | (((x) & 0x000000000000ff00ull) << 40) \ | (((x) & 0x00000000000000ffull) << 56)) __extension__ static __inline __uint64_t __bswap_64 (__uint64_t __bsx) { #if __GNUC_PREREQ (4, 3) return __builtin_bswap64 (__bsx); #else return __bswap_constant_64 (__bsx); #endif } #endif /* _BITS_BYTESWAP_H */