1 /* byteswap.h - Byte swapping 2 Copyright (C) 2005, 2007, 2009-2020 Free Software Foundation, Inc. 3 Written by Oskar Liljeblad <oskar@osk.mine.nu>, 2005. 4 5 This program is free software: you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as published by 7 the Free Software Foundation; either version 2.1 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18 #ifndef _GL_BYTESWAP_H 19 #define _GL_BYTESWAP_H 20 21 /* Given an unsigned 16-bit argument X, return the value corresponding to 22 X with reversed byte order. */ 23 #define bswap_16(x) ((((x) & 0x00FF) << 8) | \ 24 (((x) & 0xFF00) >> 8)) 25 26 /* Given an unsigned 32-bit argument X, return the value corresponding to 27 X with reversed byte order. */ 28 #define bswap_32(x) ((((x) & 0x000000FF) << 24) | \ 29 (((x) & 0x0000FF00) << 8) | \ 30 (((x) & 0x00FF0000) >> 8) | \ 31 (((x) & 0xFF000000) >> 24)) 32 33 /* Given an unsigned 64-bit argument X, return the value corresponding to 34 X with reversed byte order. */ 35 #define bswap_64(x) ((((x) & 0x00000000000000FFULL) << 56) | \ 36 (((x) & 0x000000000000FF00ULL) << 40) | \ 37 (((x) & 0x0000000000FF0000ULL) << 24) | \ 38 (((x) & 0x00000000FF000000ULL) << 8) | \ 39 (((x) & 0x000000FF00000000ULL) >> 8) | \ 40 (((x) & 0x0000FF0000000000ULL) >> 24) | \ 41 (((x) & 0x00FF000000000000ULL) >> 40) | \ 42 (((x) & 0xFF00000000000000ULL) >> 56)) 43 44 #endif /* _GL_BYTESWAP_H */