endian.h

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/*	$NetBSD: endian.h,v 1.3 2000/03/17 11:47:43 soren Exp $	*/

/*
 * Copyright (c) 1987, 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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.
 *
 *	@(#)endian.h	8.1 (Berkeley) 6/11/93
 */

#ifndef _SYS_ENDIAN_H_
#define _SYS_ENDIAN_H_

/*
 * Definitions for byte order, according to byte significance from low
 * address to high.
 */
#define	_LITTLE_ENDIAN	1234	/* LSB first: i386, vax */
#define	_BIG_ENDIAN	4321	/* MSB first: 68000, ibm, net */
#define	_PDP_ENDIAN	3412	/* LSB first in word, MSW first in long */

#include <machine/endian_machdep.h>

/*
 * Define the order of 32-bit words in 64-bit words.
 */
#if _BYTE_ORDER == _LITTLE_ENDIAN
#define _QUAD_HIGHWORD 1
#define _QUAD_LOWWORD 0
#endif

#if _BYTE_ORDER == _BIG_ENDIAN
#define _QUAD_HIGHWORD 0
#define _QUAD_LOWWORD 1
#endif


#ifndef _POSIX_SOURCE
/*
 *  Traditional names for byteorder.  These are defined as the numeric
 *  sequences so that third party code can "#define XXX_ENDIAN" and not
 *  cause errors.
 */
#define	LITTLE_ENDIAN	1234		/* LSB first: i386, vax */
#define	BIG_ENDIAN	4321		/* MSB first: 68000, ibm, net */
#define	PDP_ENDIAN	3412		/* LSB first in word, MSW first in long */
#define BYTE_ORDER	_BYTE_ORDER

#ifndef _LOCORE
/* C-family endian-ness definitions */

#include <sys/cdefs.h>
#include <sys/types.h>

typedef u_int32_t	in_addr_t;
typedef u_int16_t	in_port_t;

__BEGIN_DECLS
in_addr_t	htonl __P((in_addr_t)) __attribute__((__const__));
in_port_t	htons __P((in_port_t)) __attribute__((__const__));
in_addr_t	ntohl __P((in_addr_t)) __attribute__((__const__));
in_port_t	ntohs __P((in_port_t)) __attribute__((__const__));
__END_DECLS

/*
 * Macros for network/external number representation conversion.
 */
#if BYTE_ORDER == BIG_ENDIAN && !defined(lint)
#define	ntohl(x)	(x)
#define	ntohs(x)	(x)
#define	htonl(x)	(x)
#define	htons(x)	(x)

#define	NTOHL(x)	(void) (x)
#define	NTOHS(x)	(void) (x)
#define	HTONL(x)	(void) (x)
#define	HTONS(x)	(void) (x)

#else	/* LITTLE_ENDIAN || !defined(lint) */

#define	NTOHL(x)	(x) = ntohl((in_addr_t)(x))
#define	NTOHS(x)	(x) = ntohs((in_port_t)(x))
#define	HTONL(x)	(x) = htonl((in_addr_t)(x))
#define	HTONS(x)	(x) = htons((in_port_t)(x))
#endif	/* LITTLE_ENDIAN || !defined(lint) */

/*
 * Macros to convert to a specific endianness.
 */

#include <machine/bswap.h>

#if BYTE_ORDER == BIG_ENDIAN

#define htobe16(x)	(x)
#define htobe32(x)	(x)
#define htobe64(x)	(x)
#define htole16(x)	bswap16((u_int16_t)(x))
#define htole32(x)	bswap32((u_int32_t)(x))
#define htole64(x)	bswap64((u_int64_t)(x))

#define HTOBE16(x)	(void) (x)
#define HTOBE32(x)	(void) (x)
#define HTOBE64(x)	(void) (x)
#define HTOLE16(x)	(x) = bswap16((u_int16_t)(x))
#define HTOLE32(x)	(x) = bswap32((u_int32_t)(x))
#define HTOLE64(x)	(x) = bswap64((u_int64_t)(x))

#else	/* LITTLE_ENDIAN */

#define htobe16(x)	bswap16((u_int16_t)(x))
#define htobe32(x)	bswap32((u_int32_t)(x))
#define htobe64(x)	bswap64((u_int64_t)(x))
#define htole16(x)	(x)
#define htole32(x)	(x)
#define htole64(x)	(x)

#define HTOBE16(x)	(x) = bswap16((u_int16_t)(x))
#define HTOBE32(x)	(x) = bswap32((u_int32_t)(x))
#define HTOBE64(x)	(x) = bswap64((u_int64_t)(x))
#define HTOLE16(x)	(void) (x)
#define HTOLE32(x)	(void) (x)
#define HTOLE64(x)	(void) (x)

#endif	/* LITTLE_ENDIAN */

#define be16toh(x)	htobe16(x)
#define be32toh(x)	htobe32(x)
#define be64toh(x)	htobe64(x)
#define le16toh(x)	htole16(x)
#define le32toh(x)	htole32(x)
#define le64toh(x)	htole64(x)

#define BE16TOH(x)	HTOBE16(x)
#define BE32TOH(x)	HTOBE32(x)
#define BE64TOH(x)	HTOBE64(x)
#define LE16TOH(x)	HTOLE16(x)
#define LE32TOH(x)	HTOLE32(x)
#define LE64TOH(x)	HTOLE64(x)

#endif /* !_LOCORE */
#endif /* !_POSIX_SOURCE */
#endif /* !_SYS_ENDIAN_H_ */