usr/src/lib/libc/port/gen/swab.c
author stevel@tonic-gate
Tue, 14 Jun 2005 00:00:00 -0700
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OpenSolaris Launch
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/*
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 * CDDL HEADER START
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 *
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 * The contents of this file are subject to the terms of the
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 * Common Development and Distribution License, Version 1.0 only
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 * (the "License").  You may not use this file except in compliance
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 * with the License.
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 *
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 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
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 * or http://www.opensolaris.org/os/licensing.
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 * See the License for the specific language governing permissions
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 * and limitations under the License.
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 *
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 * When distributing Covered Code, include this CDDL HEADER in each
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 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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 * If applicable, add the following below this CDDL HEADER, with the
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 * fields enclosed by brackets "[]" replaced with your own identifying
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 * information: Portions Copyright [yyyy] [name of copyright owner]
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 *
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 * CDDL HEADER END
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 */
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/*
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 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
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 * Use is subject to license terms.
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 */
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#pragma ident	"%Z%%M%	%I%	%E% SMI"
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/*	Copyright (c) 1988 AT&T	*/
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/*	  All Rights Reserved  	*/
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/*
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 * Swab bytes
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 */
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#pragma weak swab = _swab
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#include "synonyms.h"
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#include <sys/types.h>
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#include <stdlib.h>
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#define	STEP	(void)((temp = *from++), (*to++ = *from++), (*to++ = temp))
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void
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swab(const char *src, char *dest, ssize_t n)
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{
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	char temp;
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	const char *from = (const char *)src;
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	char *to = (char *)dest;
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	if (n <= 1)
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		return;
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	n >>= 1; n++;
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	/* round to multiple of 8 */
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	while ((--n) & 07)
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		STEP;
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	n >>= 3;
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	while (--n >= 0) {
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		STEP; STEP; STEP; STEP;
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		STEP; STEP; STEP; STEP;
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	}
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}