1 /* $NetBSD: swab.c,v 1.11 2001/05/22 18:56:33 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1988, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Jeffrey Mogul. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)swab.c 8.1 (Berkeley) 6/4/93"; 43 #else 44 __RCSID("$NetBSD: swab.c,v 1.11 2001/05/22 18:56:33 christos Exp $"); 45 #endif 46 #endif /* LIBC_SCCS and not lint */ 47 48 #include <assert.h> 49 #include <unistd.h> 50 51 void 52 swab(const void *from, void *to, size_t len) 53 { 54 char temp; 55 const char *fp; 56 char *tp; 57 58 _DIAGASSERT(from != NULL); 59 _DIAGASSERT(to != NULL); 60 61 len = (len / 2) + 1; 62 fp = (const char *)from; 63 tp = (char *)to; 64 #define STEP temp = *fp++,*tp++ = *fp++,*tp++ = temp 65 /* round to multiple of 8 */ 66 while ((--len & 07) != 0) 67 STEP; 68 len >>= 3; 69 if (len == 0) 70 return; 71 while (len-- != 0) { 72 STEP; STEP; STEP; STEP; 73 STEP; STEP; STEP; STEP; 74 } 75 } 76