1 /*
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright © 2022 Keith Packard
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above
14 * copyright notice, this list of conditions and the following
15 * disclaimer in the documentation and/or other materials provided
16 * with the distribution.
17 *
18 * 3. Neither the name of the copyright holder nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
28 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
29 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
31 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
33 * OF THE POSSIBILITY OF SUCH DAMAGE.
34 */
35
36 #ifndef __BYTESWAP_H__
37 #define __BYTESWAP_H__
38
39 #ifdef __GNUC__
40 #define bswap_16(_x) __builtin_bswap16(_x)
41 #define bswap_32(_x) __builtin_bswap32(_x)
42 #define bswap_64(_x) __builtin_bswap64(_x)
43 #else /* __GNUC__ */
44 static __inline __uint16_t
bswap_16(__uint16_t _x)45 bswap_16(__uint16_t _x)
46 {
47
48 return ((__uint16_t)((_x >> 8) | ((_x << 8) & 0xff00)));
49 }
50
51 static __inline __uint32_t
bswap_32(__uint32_t _x)52 bswap_32(__uint32_t _x)
53 {
54
55 return ((__uint32_t)((_x >> 24) | ((_x >> 8) & 0xff00) |
56 ((_x << 8) & 0xff0000) | ((_x << 24) & 0xff000000)));
57 }
58
59 static __inline __uint64_t
bswap_64(__uint64_t _x)60 bswap_64(__uint64_t _x)
61 {
62
63 return ((__uint64_t)((_x >> 56) | ((_x >> 40) & 0xff00) |
64 ((_x >> 24) & 0xff0000) | ((_x >> 8) & 0xff000000) |
65 ((_x << 8) & ((__uint64_t)0xff << 32)) |
66 ((_x << 24) & ((__uint64_t)0xff << 40)) |
67 ((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56))));
68 }
69 #endif /* !__GNUC__ */
70
71 #endif /* __BYTESWAP_H__ */
72
