12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879 |
- /* Macros and inline functions to swap the order of bytes in integer values.
- Copyright (C) 1997-2019 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
- <http://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 */
|