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endian.h revision 1.11 
      1 /*
      2  * Copyright (c) 1987, 1991 Regents of the University of California.
      3  * All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that the following conditions
      7  * are met:
      8  * 1. Redistributions of source code must retain the above copyright
      9  *    notice, this list of conditions and the following disclaimer.
     10  * 2. Redistributions in binary form must reproduce the above copyright
     11  *    notice, this list of conditions and the following disclaimer in the
     12  *    documentation and/or other materials provided with the distribution.
     13  * 3. All advertising materials mentioning features or use of this software
     14  *    must display the following acknowledgement:
     15  *	This product includes software developed by the University of
     16  *	California, Berkeley and its contributors.
     17  * 4. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  *
     33  *	from: @(#)endian.h	7.8 (Berkeley) 4/3/91
     34  *	$Id: endian.h,v 1.11 1994/07/15 21:10:21 mycroft Exp $
     35  */
     36 
     37 #ifndef _MACHINE_ENDIAN_H_
     38 #define _MACHINE_ENDIAN_H_
     39 
     40 /*
     41  * Define the order of 32-bit words in 64-bit words.
     42  */
     43 #define _QUAD_HIGHWORD 1
     44 #define _QUAD_LOWWORD 0
     45 
     46 
     47 #ifndef _POSIX_SOURCE
     48 /*
     49  * Definitions for byte order, according to byte significance from low
     50  * address to high.
     51  */
     52 #define	LITTLE_ENDIAN	1234	/* LSB first: i386, vax */
     53 #define	BIG_ENDIAN	4321	/* MSB first: 68000, ibm, net */
     54 #define	PDP_ENDIAN	3412	/* LSB first in word, MSW first in long */
     55 
     56 #define	BYTE_ORDER	LITTLE_ENDIAN
     57 
     58 #include <sys/cdefs.h>
     59 
     60 __BEGIN_DECLS
     61 unsigned long   htonl __P((unsigned long));
     62 unsigned short  htons __P((unsigned short));
     63 unsigned long   ntohl __P((unsigned long));
     64 unsigned short  ntohs __P((unsigned short));
     65 __END_DECLS
     66 
     67 
     68 #ifdef __GNUC__
     69 
     70 #if defined(KERNEL) && !defined(I386_CPU)
     71 #define __byte_swap_long(x) \
     72 ({ register unsigned long __x = (x); \
     73    asm ("bswap %1" \
     74 	: "=r" (__x) \
     75 	: "0" (__x)); \
     76    __x; })
     77 #else
     78 #define __byte_swap_long(x) \
     79 ({ register unsigned long __x = (x); \
     80    asm ("rorw $8, %w1\n\trorl $16, %1\n\trorw $8, %w1" \
     81 	: "=r" (__x) \
     82 	: "0" (__x)); \
     83    __x; })
     84 #endif	/* KERNEL && ... */
     85 
     86 #define __byte_swap_word(x) \
     87 ({ register unsigned short __x = (x); \
     88    asm ("rorw $8, %w1" \
     89 	: "=r" (__x) \
     90 	: "0" (__x)); \
     91    __x; })
     92 
     93 #define	ntohl(x)	__byte_swap_long(x)
     94 #define	ntohs(x)	__byte_swap_word(x)
     95 #define	htonl(x)	__byte_swap_long(x)
     96 #define	htons(x)	__byte_swap_word(x)
     97 
     98 #endif	/* __GNUC__ */
     99 
    100 
    101 /*
    102  * Macros for network/external number representation conversion.
    103  */
    104 #define	NTOHL(x)	(x) = ntohl((unsigned long)(x))
    105 #define	NTOHS(x)	(x) = ntohs((unsigned short)(x))
    106 #define	HTONL(x)	(x) = htonl((unsigned long)(x))
    107 #define	HTONS(x)	(x) = htons((unsigned short)(x))
    108 
    109 #endif /* _POSIX_SOURCE */
    110 
    111 #endif /* _MACHINE_ENDIAN_H_ */
    112