Commit | Line | Data |
---|---|---|
984263bc MD |
1 | /* |
2 | * Copyright (c) 1988, 1993 | |
3 | * The Regents of the University of California. All rights reserved. | |
4 | * | |
5 | * This code is derived from software contributed to Berkeley by | |
6 | * Jeffrey Mogul. | |
7 | * | |
8 | * Redistribution and use in source and binary forms, with or without | |
9 | * modification, are permitted provided that the following conditions | |
10 | * are met: | |
11 | * 1. Redistributions of source code must retain the above copyright | |
12 | * notice, this list of conditions and the following disclaimer. | |
13 | * 2. Redistributions in binary form must reproduce the above copyright | |
14 | * notice, this list of conditions and the following disclaimer in the | |
15 | * documentation and/or other materials provided with the distribution. | |
dc71b7ab | 16 | * 3. Neither the name of the University nor the names of its contributors |
984263bc MD |
17 | * may be used to endorse or promote products derived from this software |
18 | * without specific prior written permission. | |
19 | * | |
20 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
21 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
22 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
23 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
24 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
25 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
26 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
27 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
28 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
29 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
30 | * SUCH DAMAGE. | |
1de703da MD |
31 | * |
32 | * @(#)swab.c 8.1 (Berkeley) 6/4/93 | |
0d5acd74 | 33 | * $FreeBSD: head/lib/libc/string/swab.c 251069 2013-05-28 20:57:40Z emaste $ |
984263bc MD |
34 | */ |
35 | ||
716024cd | 36 | #include <unistd.h> |
984263bc MD |
37 | |
38 | void | |
716024cd | 39 | swab(const void * __restrict from, void * __restrict to, ssize_t len) |
984263bc | 40 | { |
660c873b DR |
41 | unsigned long temp; |
42 | int n; | |
43 | char *fp, *tp; | |
984263bc | 44 | |
0d5acd74 JM |
45 | if (len <= 0) |
46 | return; | |
716024cd | 47 | n = len >> 1; |
984263bc MD |
48 | fp = (char *)from; |
49 | tp = (char *)to; | |
50 | #define STEP temp = *fp++,*tp++ = *fp++,*tp++ = temp | |
51 | /* round to multiple of 8 */ | |
716024cd | 52 | for (; n & 0x7; --n) |
984263bc | 53 | STEP; |
716024cd | 54 | for (n >>= 3; n > 0; --n) { |
984263bc MD |
55 | STEP; STEP; STEP; STEP; |
56 | STEP; STEP; STEP; STEP; | |
57 | } | |
58 | } |