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endian.h revision 1.14 
      1 /*	$NetBSD: endian.h,v 1.14 1994/10/27 04:16:03 cgd Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1987, 1991 Regents of the University of California.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)endian.h	7.8 (Berkeley) 4/3/91
     36  */
     37 
     38 #ifndef _I386_ENDIAN_H_
     39 #define	_I386_ENDIAN_H_
     40 
     41 /*
     42  * Define the order of 32-bit words in 64-bit words.
     43  */
     44 #define _QUAD_HIGHWORD 1
     45 #define _QUAD_LOWWORD 0
     46 
     47 
     48 #ifndef _POSIX_SOURCE
     49 /*
     50  * Definitions for byte order, according to byte significance from low
     51  * address to high.
     52  */
     53 #define	LITTLE_ENDIAN	1234	/* LSB first: i386, vax */
     54 #define	BIG_ENDIAN	4321	/* MSB first: 68000, ibm, net */
     55 #define	PDP_ENDIAN	3412	/* LSB first in word, MSW first in long */
     56 
     57 #define	BYTE_ORDER	LITTLE_ENDIAN
     58 
     59 #include <sys/cdefs.h>
     60 
     61 __BEGIN_DECLS
     62 unsigned long   htonl __P((unsigned long));
     63 unsigned short  htons __P((unsigned short));
     64 unsigned long   ntohl __P((unsigned long));
     65 unsigned short  ntohs __P((unsigned short));
     66 __END_DECLS
     67 
     68 
     69 #ifdef __GNUC__
     70 
     71 #if defined(KERNEL) && !defined(I386_CPU)
     72 #define __byte_swap_long(x) \
     73 ({ register unsigned long __x = (x); \
     74    __asm ("bswap %1" \
     75 	: "=r" (__x) \
     76 	: "0" (__x)); \
     77    __x; })
     78 #else
     79 #define __byte_swap_long(x) \
     80 ({ register unsigned long __x = (x); \
     81    __asm ("rorw $8, %w1\n\trorl $16, %1\n\trorw $8, %w1" \
     82 	: "=r" (__x) \
     83 	: "0" (__x)); \
     84    __x; })
     85 #endif	/* KERNEL && ... */
     86 
     87 #define __byte_swap_word(x) \
     88 ({ register unsigned short __x = (x); \
     89    __asm ("rorw $8, %w1" \
     90 	: "=r" (__x) \
     91 	: "0" (__x)); \
     92    __x; })
     93 
     94 #define	ntohl(x)	__byte_swap_long(x)
     95 #define	ntohs(x)	__byte_swap_word(x)
     96 #define	htonl(x)	__byte_swap_long(x)
     97 #define	htons(x)	__byte_swap_word(x)
     98 
     99 #endif	/* __GNUC__ */
    100 
    101 
    102 /*
    103  * Macros for network/external number representation conversion.
    104  */
    105 #define	NTOHL(x)	(x) = ntohl((unsigned long)(x))
    106 #define	NTOHS(x)	(x) = ntohs((unsigned short)(x))
    107 #define	HTONL(x)	(x) = htonl((unsigned long)(x))
    108 #define	HTONS(x)	(x) = htons((unsigned short)(x))
    109 
    110 #endif /* _POSIX_SOURCE */
    111 
    112 #endif /* !_I386_ENDIAN_H_ */
    113