/* $FreeBSD$ */
/* $NetBSD: citrus_region.h,v 1.7 2008/02/09 14:56:20 junyoung Exp $ */

/*-
 * Copyright (c)2003 Citrus Project,
 * 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.
 *
 */

#ifndef _CITRUS_REGION_H_
#define _CITRUS_REGION_H_

#include <sys/types.h>

struct _citrus_region {
	void	*r_head;
	size_t	 r_size;
};

static __inline void
_citrus_region_init(struct _citrus_region *r, void *h, size_t sz)
{

	r->r_head = h;
	r->r_size = sz;
}

static __inline void *
_citrus_region_head(const struct _citrus_region *r)
{

	return (r->r_head);
}

static __inline size_t
_citrus_region_size(const struct _citrus_region *r)
{

	return (r->r_size);
}

static __inline int
_citrus_region_check(const struct _citrus_region *r, size_t ofs, size_t sz)
{

	return (r->r_size >= ofs + sz ? 0 : -1);
}

static __inline void *
_citrus_region_offset(const struct _citrus_region *r, size_t pos)
{

	return ((void *)((uint8_t *)r->r_head + pos));
}

static __inline uint8_t
_citrus_region_peek8(const struct _citrus_region *r, size_t pos)
{

	return (*(uint8_t *)_citrus_region_offset(r, pos));
}

static __inline uint16_t
_citrus_region_peek16(const struct _citrus_region *r, size_t pos)
{
	uint16_t val;

	memcpy(&val, _citrus_region_offset(r, pos), (size_t)2);
	return (val);
}

static __inline uint32_t
_citrus_region_peek32(const struct _citrus_region *r, size_t pos)
{
	uint32_t val;

	memcpy(&val, _citrus_region_offset(r, pos), (size_t)4);
	return (val);
}

static __inline int
_citrus_region_get_subregion(struct _citrus_region *subr,
    const struct _citrus_region *r, size_t ofs, size_t sz)
{

	if (_citrus_region_check(r, ofs, sz))
		return (-1);
	_citrus_region_init(subr, _citrus_region_offset(r, ofs), sz);
	return (0);
}

#endif
