1 /*	$NetBSD: ioccom.h,v 1.8 2005/12/11 12:25:20 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1982, 1986, 1990, 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  *	@(#)ioccom.h	8.3 (Berkeley) 1/9/95
32  */
33 #ifndef	_SYS_IOCCOM_H_
34 #define	_SYS_IOCCOM_H_
35 
36 /*
37  * Ioctl's have the command encoded in the lower word, and the size of
38  * any in or out parameters in the upper word.  The high 3 bits of the
39  * upper word are used to encode the in/out status of the parameter.
40  */
41 #define	IOCPARM_MASK	0x1fff		/* parameter length, at most 13 bits */
42 
43 #define	IOCPARM_LEN(x)	(((x) >> 16) & IOCPARM_MASK)
44 #define	IOCBASECMD(x)	((x) & ~(IOCPARM_MASK << 16))
45 #define	IOCGROUP(x)	(((x) >> 8) & 0xff)
46 
47 #define	IOCPARM_MAX	NBPG	/* max size of ioctl args, mult. of NBPG */
48 				/* no parameters */
49 #define	IOC_VOID	(unsigned long)0x20000000
50 				/* copy parameters out */
51 #define	IOC_OUT		(unsigned long)0x40000000
52 				/* copy parameters in */
53 #define	IOC_IN		(unsigned long)0x80000000
54 				/* copy parameters in and out */
55 #define	IOC_INOUT	(IOC_IN|IOC_OUT)
56 				/* mask for IN/OUT/VOID */
57 #define	IOC_DIRMASK	(unsigned long)0xe0000000
58 
59 #define _IOC(inout,group,num,len)   (inout | ((len & IOCPARM_MASK) << 16) | ((group) << 8) | (num))
60 
61 #define	_IO(g,n)	_IOC(IOC_VOID,	(g), (n), 0)
62 #define	_IOR(g,n,t)	_IOC(IOC_OUT,	(g), (n), sizeof(t))
63 #define	_IOW(g,n,t)	_IOC(IOC_IN,	(g), (n), sizeof(t))
64 
65 /* this should be _IORW, but stdio got there first */
66 #define	_IOWR(g,n,t)	_IOC(IOC_INOUT,	(g), (n), sizeof(t))
67 
68 #endif /* !_SYS_IOCCOM_H_ */
69