[apple/libc.git] / string / swab-fbsd.c

/*
 * Copyright (c) 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Jeffrey Mogul.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)swab.c	8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/lib/libc/string/swab.c,v 1.5 2002/08/30 20:33:05 robert Exp $");

#include <string.h>

void
swab(const void * __restrict from, void * __restrict to, ssize_t len)
{
	unsigned long temp;
	int n;
	char *fp, *tp;

	if (len <= 0)
		return;
	n = len >> 1;
	fp = (char *)from;
	tp = (char *)to;
#define	STEP	temp = *fp++,*tp++ = *fp++,*tp++ = temp
	/* round to multiple of 8 */
	for (; n & 0x7; --n)
		STEP;
	for (n >>= 3; n > 0; --n) {
		STEP; STEP; STEP; STEP;
		STEP; STEP; STEP; STEP;
	}
}
Commit	Line	Data
224c7076 A	1	/*
224c7076 A	2	* Copyright (c) 1988, 1993
e9ce8d39 A	3	* The Regents of the University of California. All rights reserved.
e9ce8d39 A	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
224c7076 A	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	}