root/sys/sys/ioccom.h
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1982, 1986, 1990, 1993, 1994
 *      The Regents of the University of California.  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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 _SYS_IOCCOM_H_
#define _SYS_IOCCOM_H_

/*
 * Ioctl's have the command encoded in the lower word, and the size of
 * any in or out parameters in the upper word.  The high 3 bits of the
 * upper word are used to encode the in/out status of the parameter.
 *
 *       31 29 28                     16 15            8 7             0
 *      +---------------------------------------------------------------+
 *      | I/O | Parameter Length        | Command Group | Command       |
 *      +---------------------------------------------------------------+
 */
#define IOCPARM_SHIFT   13              /* number of bits for ioctl size */
#define IOCPARM_MASK    ((1 << IOCPARM_SHIFT) - 1) /* parameter length mask */
#define IOCPARM_LEN(x)  (((x) >> 16) & IOCPARM_MASK)
#define IOCBASECMD(x)   ((x) & ~(IOCPARM_MASK << 16))
#define IOCGROUP(x)     (((x) >> 8) & 0xff)

#define IOCPARM_MAX     (1 << IOCPARM_SHIFT) /* max size of ioctl */

#define IOC_VOID        0x20000000UL    /* no parameters */
#define IOC_OUT         0x40000000UL    /* copy out parameters */
#define IOC_IN          0x80000000UL    /* copy in parameters */
#define IOC_INOUT       (IOC_IN|IOC_OUT)/* copy parameters in and out */
#define IOC_DIRMASK     (IOC_VOID|IOC_OUT|IOC_IN)/* mask for IN/OUT/VOID */

#define _IOC(inout,group,num,len)       ((unsigned long) \
        ((inout) | (((len) & IOCPARM_MASK) << 16) | ((group) << 8) | (num)))
#define _IO(g,n)        _IOC(IOC_VOID,  (g), (n), 0)
#define _IOWINT(g,n)    _IOC(IOC_VOID,  (g), (n), sizeof(int))
#define _IOR(g,n,t)     _IOC(IOC_OUT,   (g), (n), sizeof(t))
#define _IOW(g,n,t)     _IOC(IOC_IN,    (g), (n), sizeof(t))
/* this should be _IORW, but stdio got there first */
#define _IOWR(g,n,t)    _IOC(IOC_INOUT, (g), (n), sizeof(t))
/* Replace length/type in an ioctl command. */
#define _IOC_NEWLEN(ioc, len) \
    (((~(IOCPARM_MASK << 16)) & (ioc)) | (((len) & IOCPARM_MASK) << 16))
#define _IOC_NEWTYPE(ioc, type) _IOC_NEWLEN((ioc), sizeof(type))

#ifdef _KERNEL

#if defined(COMPAT_FREEBSD6) || defined(COMPAT_FREEBSD5) || \
    defined(COMPAT_FREEBSD4) || defined(COMPAT_43)
#define IOCPARM_IVAL(x) ((int)(intptr_t)(void *)*(caddr_t *)(void *)(x))
#endif

#define _IOC_INVALID    (_IOC_VOID|_IOC_INOUT)  /* Never valid cmd value,
                                                   use as filler */

#elif !defined(_STANDALONE)

#include <sys/cdefs.h>

__BEGIN_DECLS
int     ioctl(int, unsigned long, ...);
__END_DECLS

#endif

#endif /* !_SYS_IOCCOM_H_ */