xref: /onnv-gate/usr/src/lib/libc/i386/gen/byteorder.s (revision 7298:b69e27387f74)
10Sstevel@tonic-gate/*
20Sstevel@tonic-gate * CDDL HEADER START
30Sstevel@tonic-gate *
40Sstevel@tonic-gate * The contents of this file are subject to the terms of the
54292Sab196087 * Common Development and Distribution License (the "License").
64292Sab196087 * You may not use this file except in compliance with the License.
70Sstevel@tonic-gate *
80Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
90Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
100Sstevel@tonic-gate * See the License for the specific language governing permissions
110Sstevel@tonic-gate * and limitations under the License.
120Sstevel@tonic-gate *
130Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
140Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
150Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
160Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
170Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
180Sstevel@tonic-gate *
190Sstevel@tonic-gate * CDDL HEADER END
200Sstevel@tonic-gate */
210Sstevel@tonic-gate/*
224292Sab196087 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
230Sstevel@tonic-gate * Use is subject to license terms.
240Sstevel@tonic-gate */
250Sstevel@tonic-gate
26*7298SMark.J.Nelson@Sun.COM	.file	"byteorder.s"
270Sstevel@tonic-gate
280Sstevel@tonic-gate#include "SYS.h"
290Sstevel@tonic-gate
304292Sab196087	/*
314292Sab196087	 * NOTE: htonl/ntohl are identical routines, as are htons/ntohs.
324292Sab196087	 * As such, they could be implemented as a single routine, using
334292Sab196087	 * multiple ALTENTRY/SET_SIZE definitions. We don't do this so
344292Sab196087	 * that they will have unique addresses, allowing DTrace and
354292Sab196087	 * other debuggers to tell them apart.
364292Sab196087	 */
374292Sab196087
380Sstevel@tonic-gate/	unsigned long htonl( hl )
390Sstevel@tonic-gate/	unsigned long ntohl( hl )
400Sstevel@tonic-gate/	long hl;
410Sstevel@tonic-gate/	reverses the byte order of 'long hl'
420Sstevel@tonic-gate/
430Sstevel@tonic-gate	ENTRY(htonl)
444292Sab196087	movl	4(%esp), %eax	/ %eax = hl
454292Sab196087	bswap	%eax		/ reverses the byte order of %eax
464292Sab196087	ret			/ return (%eax)
474292Sab196087	SET_SIZE(htonl)
484292Sab196087
490Sstevel@tonic-gate	ENTRY(ntohl)
500Sstevel@tonic-gate	movl	4(%esp), %eax	/ %eax = hl
510Sstevel@tonic-gate	bswap	%eax		/ reverses the byte order of %eax
520Sstevel@tonic-gate	ret			/ return (%eax)
530Sstevel@tonic-gate	SET_SIZE(ntohl)
540Sstevel@tonic-gate
550Sstevel@tonic-gate/	unsigned short htons( hs )
560Sstevel@tonic-gate/	short hs;
570Sstevel@tonic-gate/
580Sstevel@tonic-gate/	reverses the byte order in hs.
590Sstevel@tonic-gate/
600Sstevel@tonic-gate	ENTRY(htons)
614292Sab196087	movl	4(%esp), %eax	/ %eax = hs
624292Sab196087	bswap	%eax		/ reverses the byte order of %eax
634292Sab196087	shrl	$16, %eax	/ moves high 16-bit to low 16-bit
644292Sab196087	ret			/ return (%eax)
654292Sab196087	SET_SIZE(htons)
664292Sab196087
670Sstevel@tonic-gate	ENTRY(ntohs)
680Sstevel@tonic-gate	movl	4(%esp), %eax	/ %eax = hs
690Sstevel@tonic-gate	bswap	%eax		/ reverses the byte order of %eax
700Sstevel@tonic-gate	shrl	$16, %eax	/ moves high 16-bit to low 16-bit
710Sstevel@tonic-gate	ret			/ return (%eax)
720Sstevel@tonic-gate	SET_SIZE(ntohs)
73