1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#ifndef _SYS__IOVEC_H_
33#define	_SYS__IOVEC_H_
34
35#include <sys/_types.h>
36
37#ifndef _SIZE_T_DECLARED
38typedef	__size_t	size_t;
39#define	_SIZE_T_DECLARED
40#endif
41
42struct iovec {
43	void	*iov_base;	/* Base address. */
44	size_t	 iov_len;	/* Length. */
45};
46
47#ifdef _KERNEL
48#define	IOVEC_INIT(iovp, base, len) 					\
49	*(iovp) = (struct iovec){ .iov_base = (base), .iov_len = (len) }
50
51/* String with length including NUL terminator */
52#define	IOVEC_INIT_CSTR(iovp, str)	do {				\
53	void *__str = (str);						\
54	IOVEC_INIT(iovp, __str, strlen(__str) + 1);			\
55} while(0)
56
57/* Object with size from sizeof() */
58#define	IOVEC_INIT_OBJ(iovp, obj)					\
59	IOVEC_INIT(iovp, &(obj), sizeof(obj))
60
61#define	IOVEC_ADVANCE(iovp, amt)	do {				\
62	struct iovec *__iovp = (iovp);					\
63	size_t __amt = (amt);						\
64	KASSERT(__amt <= __iovp->iov_len, ("%s: amount %zu > iov_len	\
65	    %zu", __func__, __amt, __iovp->iov_len));			\
66	__iovp->iov_len -= __amt;					\
67	__iovp->iov_base = (char *)__iovp->iov_base + __amt;		\
68} while(0)
69#endif /* _KERNEL */
70
71#endif /* !_SYS__IOVEC_H_ */
72