freebsd-dev/sys/sparc64/include/endian.h
Marius Strobl a1610d83b8 In the replacement text of the __bswapN_const() macros encapsulate the
argument in parentheses so these macros are safe to use and invocations
with an expression as the argument like __bswap32_const(42 << 23 | 13)
work as expected. Additionally, mask all the individually shifted bytes
as appropriate so the bytes which exceed the width of the respective
__bswapN_const() macro in invocations like __bswap16_const(0xdead600d)
are ignored like it's the case with the corresponding __bswapN_var()
function.

MFC after:	3 days
2006-10-30 21:50:11 +00:00

123 lines
4.1 KiB
C

/*-
* 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.
* 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) 6/10/93
* $FreeBSD$
*/
#ifndef _MACHINE_ENDIAN_H_
#define _MACHINE_ENDIAN_H_
#include <sys/cdefs.h>
#include <sys/_types.h>
/*
* Define the order of 32-bit words in 64-bit words.
*/
#define _QUAD_HIGHWORD 0
#define _QUAD_LOWWORD 1
/*
* 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 */
#define _BYTE_ORDER _BIG_ENDIAN
/*
* Deprecated variants that don't have enough underscores to be useful in more
* strict namespaces.
*/
#if __BSD_VISIBLE
#define LITTLE_ENDIAN _LITTLE_ENDIAN
#define BIG_ENDIAN _BIG_ENDIAN
#define PDP_ENDIAN _PDP_ENDIAN
#define BYTE_ORDER _BYTE_ORDER
#endif
#if defined(__GNUCLIKE_BUILTIN_CONSTANT_P) && defined(__OPTIMIZE__)
#define __is_constant(x) __builtin_constant_p(x)
#else
#define __is_constant(x) 0
#endif
#define __bswap16_const(x) ((((x) >> 8) & 0xff) | \
(((x) << 8) & 0xff00))
#define __bswap32_const(x) ((((x) >> 24) & 0xff) | \
(((x) >> 8) & 0xff00) | (((x) << 8) & 0xff0000) | \
(((x) << 24) & 0xff000000))
#define __bswap64_const(x) ((((x) >> 56) & 0xff) | \
(((x) >> 40) & 0xff00) | (((x) >> 24) & 0xff0000) | \
(((x) >> 8) & 0xff000000) | \
(((x) << 8) & ((__uint64_t)0xff << 32)) | \
(((x) << 24) & ((__uint64_t)0xff << 40)) | \
(((x) << 40) & ((__uint64_t)0xff << 48)) | \
(((x) << 56) & ((__uint64_t)0xff << 56)))
static __inline __uint16_t
__bswap16_var(__uint16_t _x)
{
return ((_x >> 8) | ((_x << 8) & 0xff00));
}
static __inline __uint32_t
__bswap32_var(__uint32_t _x)
{
return ((_x >> 24) | ((_x >> 8) & 0xff00) | ((_x << 8) & 0xff0000) |
((_x << 24) & 0xff000000));
}
static __inline __uint64_t
__bswap64_var(__uint64_t _x)
{
return ((_x >> 56) | ((_x >> 40) & 0xff00) | ((_x >> 24) & 0xff0000) |
((_x >> 8) & 0xff000000) | ((_x << 8) & ((__uint64_t)0xff << 32)) |
((_x << 24) & ((__uint64_t)0xff << 40)) |
((_x << 40) & ((__uint64_t)0xff << 48)) | ((_x << 56)));
}
#define __bswap16(x) (__is_constant(x) ? __bswap16_const(x) : \
__bswap16_var(x))
#define __bswap32(x) (__is_constant(x) ? __bswap32_const(x) : \
__bswap32_var(x))
#define __bswap64(x) (__is_constant(x) ? __bswap64_const(x) : \
__bswap64_var(x))
#define __htonl(x) ((__uint32_t)(x))
#define __htons(x) ((__uint16_t)(x))
#define __ntohl(x) ((__uint32_t)(x))
#define __ntohs(x) ((__uint16_t)(x))
#endif /* !_MACHINE_ENDIAN_H_ */