projects / apple / libc.git / blame
| Commit | Line | Data |
|---|---|---|
| 224c7076 A |
1 | /* |
| 2 | * Copyright (c) 1988, 1993 | |
| e9ce8d39 A |
3 | * The Regents of the University of California. All rights reserved. |
| 4 | * | |
| 224c7076 A |
5 | * This code is derived from software contributed to Berkeley by |
| 6 | * Jeffrey Mogul. | |
| 7 | * | |
| e9ce8d39 A |
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. | |
| 16 | * 3. All advertising materials mentioning features or use of this software | |
| 17 | * must display the following acknowledgement: | |
| 18 | * This product includes software developed by the University of | |
| 19 | * California, Berkeley and its contributors. | |
| 20 | * 4. Neither the name of the University nor the names of its contributors | |
| 21 | * may be used to endorse or promote products derived from this software | |
| 22 | * without specific prior written permission. | |
| 23 | * | |
| 24 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
| 25 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 26 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 27 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
| 28 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
| 29 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
| 30 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| 31 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
| 32 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
| 33 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
| 34 | * SUCH DAMAGE. | |
| 35 | */ | |
| 36 | ||
| 5b2abdfb | 37 | #if defined(LIBC_SCCS) && !defined(lint) |
| 224c7076 | 38 | static char sccsid[] = "@(#)swab.c 8.1 (Berkeley) 6/4/93"; |
| 5b2abdfb | 39 | #endif /* LIBC_SCCS and not lint */ |
| 9385eb3d | 40 | #include <sys/cdefs.h> |
| 224c7076 | 41 | __FBSDID("$FreeBSD: src/lib/libc/string/swab.c,v 1.5 2002/08/30 20:33:05 robert Exp $"); |
| e9ce8d39 | 42 | |
| 224c7076 | 43 | #include <string.h> |
| e9ce8d39 | 44 | |
| 224c7076 A |
45 | void |
| 46 | swab(const void * __restrict from, void * __restrict to, ssize_t len) | |
| e9ce8d39 | 47 | { |
| 224c7076 A |
48 | unsigned long temp; |
| 49 | int n; | |
| 50 | char *fp, *tp; | |
| e9ce8d39 | 51 | |
| 224c7076 A |
52 | if (len <= 0) |
| 53 | return; | |
| 54 | n = len >> 1; | |
| 55 | fp = (char *)from; | |
| 56 | tp = (char *)to; | |
| 57 | #define STEP temp = *fp++,*tp++ = *fp++,*tp++ = temp | |
| 58 | /* round to multiple of 8 */ | |
| 59 | for (; n & 0x7; --n) | |
| 60 | STEP; | |
| 61 | for (n >>= 3; n > 0; --n) { | |
| 62 | STEP; STEP; STEP; STEP; | |
| 63 | STEP; STEP; STEP; STEP; | |
| 64 | } | |
| e9ce8d39 | 65 | } |