1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright 2008 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26
27 /* Copyright (c) 1988 AT&T */
28 /* All Rights Reserved */
29
30 /*
31 * Swab bytes
32 */
33
34 #pragma weak _swab = swab
35
36 #include "lint.h"
37 #include <sys/types.h>
38 #include <stdlib.h>
39
40
41 #define STEP (void)((temp = *from++), (*to++ = *from++), (*to++ = temp))
42
43 void
swab(const char * src,char * dest,ssize_t n)44 swab(const char *src, char *dest, ssize_t n)
45 {
46 char temp;
47 const char *from = (const char *)src;
48 char *to = (char *)dest;
49
50 if (n <= 1)
51 return;
52 n >>= 1; n++;
53 /* round to multiple of 8 */
54 while ((--n) & 07)
55 STEP;
56 n >>= 3;
57 while (--n >= 0) {
58 STEP; STEP; STEP; STEP;
59 STEP; STEP; STEP; STEP;
60 }
61 }
62