freebsd-nq/sys/kern/tty_tty.c
2003-01-30 12:51:32 +00:00

89 lines
2.5 KiB
C

/*-
* Copyright (c) 2003 Poul-Henning Kamp. 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/vnode.h>
static d_open_t cttyopen;
#define CDEV_MAJOR 1
static struct cdevsw ctty_cdevsw = {
/* open */ cttyopen,
/* close */ nullclose,
/* read */ noread,
/* write */ nowrite,
/* ioctl */ noioctl,
/* poll */ nopoll,
/* mmap */ nommap,
/* strategy */ nostrategy,
/* name */ "ctty",
/* maj */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ D_TTY,
};
static dev_t ctty;
static int
cttyopen(dev_t dev, int flag, int mode, struct thread *td)
{
return (ENXIO);
}
static void
ctty_clone(void *arg, char *name, int namelen, dev_t *dev)
{
if (*dev != NODEV)
return;
if (strcmp(name, "tty"))
return;
if (!(curthread->td_proc->p_flag & P_CONTROLT))
*dev = ctty;
else if (curthread->td_proc->p_session->s_ttyvp == NULL)
*dev = ctty;
else
*dev = curthread->td_proc->p_session->s_ttyvp->v_rdev;
}
static void
ctty_drvinit(void *unused)
{
EVENTHANDLER_REGISTER(dev_clone, ctty_clone, 0, 1000);
ctty = make_dev(&ctty_cdevsw, 0, 0, 0, 0666, "ctty");
}
SYSINIT(cttydev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,ctty_drvinit,NULL)