1 1.2 christos /* $NetBSD: dd_swab.c,v 1.2 2021/10/08 14:44:48 christos Exp $ */ 2 1.1 mrg 3 1.1 mrg /* 4 1.1 mrg * Copyright (c) 1988, 1993 5 1.1 mrg * The Regents of the University of California. All rights reserved. 6 1.1 mrg * 7 1.1 mrg * This code is derived from software contributed to Berkeley by 8 1.1 mrg * Jeffrey Mogul. 9 1.1 mrg * 10 1.1 mrg * Redistribution and use in source and binary forms, with or without 11 1.1 mrg * modification, are permitted provided that the following conditions 12 1.1 mrg * are met: 13 1.1 mrg * 1. Redistributions of source code must retain the above copyright 14 1.1 mrg * notice, this list of conditions and the following disclaimer. 15 1.1 mrg * 2. Redistributions in binary form must reproduce the above copyright 16 1.1 mrg * notice, this list of conditions and the following disclaimer in the 17 1.1 mrg * documentation and/or other materials provided with the distribution. 18 1.1 mrg * 3. Neither the name of the University nor the names of its contributors 19 1.1 mrg * may be used to endorse or promote products derived from this software 20 1.1 mrg * without specific prior written permission. 21 1.1 mrg * 22 1.1 mrg * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 1.1 mrg * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 1.1 mrg * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 1.1 mrg * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 1.1 mrg * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 1.1 mrg * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 1.1 mrg * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 1.1 mrg * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 1.1 mrg * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 1.1 mrg * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 1.1 mrg * SUCH DAMAGE. 33 1.1 mrg * 34 1.1 mrg * from: NetBSD: swab.c,v 1.18 2011/01/04 17:14:07 martin Exp 35 1.1 mrg */ 36 1.1 mrg 37 1.1 mrg /* This copy has no restrict on it, that dd wants */ 38 1.1 mrg 39 1.1 mrg #include <sys/cdefs.h> 40 1.1 mrg #if defined(LIBC_SCCS) && !defined(lint) 41 1.1 mrg #if 0 42 1.1 mrg static char sccsid[] = "@(#)swab.c 8.1 (Berkeley) 6/4/93"; 43 1.1 mrg #else 44 1.2 christos __RCSID("$NetBSD: dd_swab.c,v 1.2 2021/10/08 14:44:48 christos Exp $"); 45 1.1 mrg #endif 46 1.1 mrg #endif /* LIBC_SCCS and not lint */ 47 1.1 mrg 48 1.1 mrg #include <sys/types.h> 49 1.1 mrg 50 1.1 mrg #include "dd.h" 51 1.1 mrg #include "extern.h" 52 1.1 mrg 53 1.1 mrg void 54 1.1 mrg dd_swab(const void * from, void * to, ssize_t len) 55 1.1 mrg { 56 1.1 mrg char temp; 57 1.1 mrg const char *fp; 58 1.1 mrg char *tp; 59 1.1 mrg 60 1.1 mrg if (len <= 1) 61 1.1 mrg return; 62 1.1 mrg 63 1.1 mrg len /= 2; 64 1.1 mrg fp = (const char *)from; 65 1.1 mrg tp = (char *)to; 66 1.1 mrg #define STEP temp = *fp++,*tp++ = *fp++,*tp++ = temp 67 1.1 mrg 68 1.1 mrg if (__predict_false(len == 1)) { 69 1.1 mrg STEP; 70 1.1 mrg return; 71 1.1 mrg } 72 1.1 mrg 73 1.1 mrg /* round to multiple of 8 */ 74 1.2 christos for (; (len % 8) != 0; --len) 75 1.1 mrg STEP; 76 1.1 mrg len /= 8; 77 1.1 mrg if (len == 0) 78 1.1 mrg return; 79 1.1 mrg while (len-- != 0) { 80 1.1 mrg STEP; STEP; STEP; STEP; 81 1.1 mrg STEP; STEP; STEP; STEP; 82 1.1 mrg } 83 1.1 mrg } 84
Indexes created Sun Sep 21 20:09:37 GMT 2025