C++程序  |  83行  |  2.84 KB

/*-
 * Copyright (c) 2002 Thomas Moestl <tmm@FreeBSD.org>
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
 *
 * $FreeBSD$
 */

#ifndef _SYS_ENDIAN_H_
#define _SYS_ENDIAN_H_

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

/*
 * General byte order swapping functions.
 */
#define	bswap16(x)	__bswap16(x)
#define	bswap32(x)	__bswap32(x)
#define	bswap64(x)	__bswap64(x)

/*
 * Host to big endian, host to little endian, big endian to host, and little
 * endian to host byte order functions as detailed in byteorder(9).
 */
#if _BYTE_ORDER == _LITTLE_ENDIAN
#define	htobe16(x)	bswap16((x))
#define	htobe32(x)	bswap32((x))
#define	htobe64(x)	bswap64((x))
#define	htole16(x)	((uint16_t)(x))
#define	htole32(x)	((uint32_t)(x))
#define	htole64(x)	((uint64_t)(x))

#define	be16toh(x)	bswap16((x))
#define	be32toh(x)	bswap32((x))
#define	be64toh(x)	bswap64((x))
#define	le16toh(x)	((uint16_t)(x))
#define	le32toh(x)	((uint32_t)(x))
#define	le64toh(x)	((uint64_t)(x))
#else /* _BYTE_ORDER != _LITTLE_ENDIAN */
#define	htobe16(x)	((uint16_t)(x))
#define	htobe32(x)	((uint32_t)(x))
#define	htobe64(x)	((uint64_t)(x))
#define	htole16(x)	bswap16((x))
#define	htole32(x)	bswap32((x))
#define	htole64(x)	bswap64((x))

#define	be16toh(x)	((uint16_t)(x))
#define	be32toh(x)	((uint32_t)(x))
#define	be64toh(x)	((uint64_t)(x))
#define	le16toh(x)	bswap16((x))
#define	le32toh(x)	bswap32((x))
#define	le64toh(x)	bswap64((x))
#endif /* _BYTE_ORDER == _LITTLE_ENDIAN */

/*
 * The generic encoding and decoding functions have been removed since they're
 * rarely used and generate suboptimal code on platforms that allow unaligned
 * accesses
 */

#endif	/* _SYS_ENDIAN_H_ */