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/* $NetBSD: cons.c,v 1.27 1995/04/11 22:08:06 pk Exp $ */
/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* from: Utah $Hdr: cons.c 1.7 92/01/21$
*
* @(#)cons.c 8.2 (Berkeley) 1/12/94
*/
#include <sys/param.h>
#include <sys/proc.h>
#include <sys/user.h>
#include <sys/systm.h>
#include <sys/buf.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/file.h>
#include <sys/conf.h>
#include <sys/vnode.h>
#include <dev/cons.h>
struct tty *constty = NULL; /* virtual console output device */
struct consdev *cn_tab; /* physical console device info */
struct vnode *cn_devvp; /* vnode for underlying device. */
int
cnopen(dev, flag, mode, p)
dev_t dev;
int flag, mode;
struct proc *p;
{
if (cn_tab == NULL)
return (0);
/*
* always open the 'real' console device, so we don't get nailed
* later. This follows normal device semantics; they always get
* open() calls.
*/
dev = cn_tab->cn_dev;
if (cn_devvp == NULLVP) {
/* try to get a reference on its vnode, but fail silently */
cdevvp(dev, &cn_devvp);
}
return ((*cdevsw[major(dev)].d_open)(dev, flag, mode, p));
}
int
cnclose(dev, flag, mode, p)
dev_t dev;
int flag, mode;
struct proc *p;
{
struct vnode *vp;
if (cn_tab == NULL)
return (0);
/*
* If the real console isn't otherwise open, close it.
* If it's otherwise open, don't close it, because that'll
* screw up others who have it open.
*/
dev = cn_tab->cn_dev;
if (cn_devvp != NULLVP) {
/* release our reference to real dev's vnode */
vrele(cn_devvp);
cn_devvp = NULLVP;
}
if (vfinddev(dev, VCHR, &vp) && vcount(vp))
return (0);
return ((*cdevsw[major(dev)].d_close)(dev, flag, mode, p));
}
int
cnread(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
/*
* If we would redirect input, punt. This will keep strange
* things from happening to people who are using the real
* console. Nothing should be using /dev/console for
* input (except a shell in single-user mode, but then,
* one wouldn't TIOCCONS then).
*/
if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
return 0;
else if (cn_tab == NULL)
return ENXIO;
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_read)(dev, uio, flag));
}
int
cnwrite(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
/*
* Redirect output, if that's appropriate.
* If there's no real console, return ENXIO.
*/
if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
dev = constty->t_dev;
else if (cn_tab == NULL)
return ENXIO;
else
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_write)(dev, uio, flag));
}
int
cnstop(tp, flag)
struct tty *tp;
int flag;
{
}
int
cnioctl(dev, cmd, data, flag, p)
dev_t dev;
u_long cmd;
caddr_t data;
int flag;
struct proc *p;
{
int error;
/*
* Superuser can always use this to wrest control of console
* output from the "virtual" console.
*/
if (cmd == TIOCCONS && constty != NULL) {
error = suser(p->p_ucred, (u_short *) NULL);
if (error)
return (error);
constty = NULL;
return (0);
}
/*
* Redirect the ioctl, if that's appropriate.
* Note that strange things can happen, if a program does
* ioctls on /dev/console, then the console is redirected
* out from under it.
*/
if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
dev = constty->t_dev;
else if (cn_tab == NULL)
return ENXIO;
else
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p));
}
/*ARGSUSED*/
int
cnselect(dev, rw, p)
dev_t dev;
int rw;
struct proc *p;
{
/*
* Redirect the ioctl, if that's appropriate.
* I don't want to think of the possible side effects
* of console redirection here.
*/
if (constty != NULL && (cn_tab == NULL || cn_tab->cn_pri != CN_REMOTE))
dev = constty->t_dev;
else if (cn_tab == NULL)
return ENXIO;
else
dev = cn_tab->cn_dev;
return (ttselect(cn_tab->cn_dev, rw, p));
}
int
cngetc()
{
if (cn_tab == NULL)
return (0);
return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
}
int
cnputc(c)
register int c;
{
if (cn_tab == NULL)
return 0; /* XXX should be void */
if (c) {
(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
if (c == '\n')
(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
}
return 0; /* XXX should be void */
}
void
cnpollc(on)
int on;
{
static int refcount = 0;
if (cn_tab == NULL)
return;
if (!on)
--refcount;
if (refcount == 0)
(*cn_tab->cn_pollc)(cn_tab->cn_dev, on);
if (on)
++refcount;
}
void
nullcnpollc(on)
int on;
{
}
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