xref: /freebsd-10.0-release/contrib/openbsm/compat/endian_enc.h

/*-
 * Copyright (c) 2002 Thomas Moestl <tmm@FreeBSD.org>
 * Copyright (c) 2005 Robert N. M. Watson
 * 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.
 *
 * Derived from FreeBSD src/sys/sys/endian.h:1.6.
 * $P4: //depot/projects/trustedbsd/openbsm/compat/endian_enc.h#1 $
 */

#ifndef _COMPAT_ENDIAN_ENC_H_
#define _COMPAT_ENDIAN_ENC_H_

/*
 * Some systems will have the uint/int types defined here already, others
 * will need stdint.h.
 */
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

/* Alignment-agnostic encode/decode bytestream to/from little/big endian. */

static __inline uint16_t
be16dec(const void *pp)
{
	unsigned char const *p = (unsigned char const *)pp;

	return ((p[0] << 8) | p[1]);
}

static __inline uint32_t
be32dec(const void *pp)
{
	unsigned char const *p = (unsigned char const *)pp;

	return ((p[0] << 24) | (p[1] << 16) | (p[2] << 8) | p[3]);
}

static __inline uint64_t
be64dec(const void *pp)
{
	unsigned char const *p = (unsigned char const *)pp;

	return (((uint64_t)be32dec(p) << 32) | be32dec(p + 4));
}

static __inline uint16_t
le16dec(const void *pp)
{
	unsigned char const *p = (unsigned char const *)pp;

	return ((p[1] << 8) | p[0]);
}

static __inline uint32_t
le32dec(const void *pp)
{
	unsigned char const *p = (unsigned char const *)pp;

	return ((p[3] << 24) | (p[2] << 16) | (p[1] << 8) | p[0]);
}

static __inline uint64_t
le64dec(const void *pp)
{
	unsigned char const *p = (unsigned char const *)pp;

	return (((uint64_t)le32dec(p + 4) << 32) | le32dec(p));
}

static __inline void
be16enc(void *pp, uint16_t u)
{
	unsigned char *p = (unsigned char *)pp;

	p[0] = (u >> 8) & 0xff;
	p[1] = u & 0xff;
}

static __inline void
be32enc(void *pp, uint32_t u)
{
	unsigned char *p = (unsigned char *)pp;

	p[0] = (u >> 24) & 0xff;
	p[1] = (u >> 16) & 0xff;
	p[2] = (u >> 8) & 0xff;
	p[3] = u & 0xff;
}

static __inline void
be64enc(void *pp, uint64_t u)
{
	unsigned char *p = (unsigned char *)pp;

	be32enc(p, u >> 32);
	be32enc(p + 4, u & 0xffffffff);
}

static __inline void
le16enc(void *pp, uint16_t u)
{
	unsigned char *p = (unsigned char *)pp;

	p[0] = u & 0xff;
	p[1] = (u >> 8) & 0xff;
}

static __inline void
le32enc(void *pp, uint32_t u)
{
	unsigned char *p = (unsigned char *)pp;

	p[0] = u & 0xff;
	p[1] = (u >> 8) & 0xff;
	p[2] = (u >> 16) & 0xff;
	p[3] = (u >> 24) & 0xff;
}

static __inline void
le64enc(void *pp, uint64_t u)
{
	unsigned char *p = (unsigned char *)pp;

	le32enc(p, u & 0xffffffff);
	le32enc(p + 4, u >> 32);
}

#endif	/* _COMPAT_ENDIAN_ENC_H_ */