freebsd-skq/sys/kern/tty_cons.c
Andrew Moore 5bb374bc76 patch 1of2 to prevent kill -1 syslogd from hanging the console
blindly applied patch provided by Christoph Robitschko:
*** cons.c.orig	Sat Jun 12 07:57:53 1993
--- cons.c	Thu Aug 19 22:34:53 1993
***************
*** 56,61 ****
--- 56,62 ----
  #include "sys/tty.h"
  #include "sys/file.h"
  #include "sys/conf.h"
+ #include "sys/vnode.h"

  #include "cons.h"

***************
*** 105,118 ****
--- 106,130 ----
  	(*cp->cn_init)(cp);
  }

+ static struct vnode	*cnopenvp = NULLVP;
+
+
  cnopen(dev, flag, mode, p)
  	dev_t dev;
  	int flag, mode;
  	struct proc *p;
  {
+ 	int		error;
+
+
  	if (cn_tab == NULL)
  		return (0);
  	dev = cn_tab->cn_dev;
+ 	if (cnopenvp == NULLVP)
+ 		if ((error = getdevvp(dev, &cnopenvp, VCHR))) {
+ 			printf("cnopen: getdevvp returned %d !\n", error);
+ 			return(error);
+ 		}
  	return ((*cdevsw[major(dev)].d_open)(dev, flag, mode, p));
  }

***************
*** 121,130 ****
  	int flag, mode;
  	struct proc *p;
  {
  	if (cn_tab == NULL)
  		return (0);
  	dev = cn_tab->cn_dev;
! 	return ((*cdevsw[major(dev)].d_close)(dev, flag, mode, p));
  }

  cnread(dev, uio, flag)
--- 133,153 ----
  	int flag, mode;
  	struct proc *p;
  {
+ 	int		error;
+
+
  	if (cn_tab == NULL)
  		return (0);
  	dev = cn_tab->cn_dev;
! 	if (vcount(cnopenvp) <= 1)
! 		error = (*cdevsw[major(dev)].d_close)(dev, flag, mode, p);
! 	else
! 		error = 0;
! 	if (error == 0) {
! 		vrele(cnopenvp);
! 		cnopenvp = NULLVP;
! 	return(error);
! 	}
  }

  cnread(dev, uio, flag)
1993-08-20 05:46:09 +00:00

237 lines
5.7 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1991 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.
*
* @(#)cons.c 7.2 (Berkeley) 5/9/91
*
* PATCHES MAGIC LEVEL PATCH THAT GOT US HERE
* -------------------- ----- ----------------------
* CURRENT PATCH LEVEL: 1 00083
* -------------------- ----- ----------------------
*
* 16 Aug 92 Pace Willisson /dev/console redirect (xterm -C, etc.)
* 14 Mar 93 Chris G. Demetriou Moved pg() here from isa/pccons.c
*/
#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 "cons.h"
/* XXX - all this could be autoconfig()ed */
int pccnprobe(), pccninit(), pccngetc(), pccnputc();
#include "com.h"
#if NCOM > 0
int comcnprobe(), comcninit(), comcngetc(), comcnputc();
#endif
struct consdev constab[] = {
{ pccnprobe, pccninit, pccngetc, pccnputc },
#if NCOM > 0
{ comcnprobe, comcninit, comcngetc, comcnputc },
#endif
{ 0 },
};
/* end XXX */
struct tty *constty = 0; /* virtual console output device */
struct consdev *cn_tab; /* physical console device info */
struct tty *cn_tty; /* XXX: console tty struct for tprintf */
cninit()
{
register struct consdev *cp;
/*
* Collect information about all possible consoles
* and find the one with highest priority
*/
for (cp = constab; cp->cn_probe; cp++) {
(*cp->cn_probe)(cp);
if (cp->cn_pri > CN_DEAD &&
(cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
cn_tab = cp;
}
/*
* No console, we can handle it
*/
if ((cp = cn_tab) == NULL)
return;
/*
* Turn on console
*/
cn_tty = cp->cn_tp;
(*cp->cn_init)(cp);
}
static struct vnode *cnopenvp = NULLVP;
cnopen(dev, flag, mode, p)
dev_t dev;
int flag, mode;
struct proc *p;
{
int error;
if (cn_tab == NULL)
return (0);
dev = cn_tab->cn_dev;
if (cnopenvp == NULLVP)
if ((error = getdevvp(dev, &cnopenvp, VCHR))) {
printf("cnopen: getdevvp returned %d !\n", error);
return(error);
}
return ((*cdevsw[major(dev)].d_open)(dev, flag, mode, p));
}
cnclose(dev, flag, mode, p)
dev_t dev;
int flag, mode;
struct proc *p;
{
int error;
if (cn_tab == NULL)
return (0);
dev = cn_tab->cn_dev;
if (vcount(cnopenvp) <= 1)
error = (*cdevsw[major(dev)].d_close)(dev, flag, mode, p);
else
error = 0;
if (error == 0) {
vrele(cnopenvp);
cnopenvp = NULLVP;
return(error);
}
}
cnread(dev, uio, flag)
dev_t dev;
struct uio *uio;
{
if (cn_tab == NULL)
return (0);
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_read)(dev, uio, flag));
}
cnwrite(dev, uio, flag)
dev_t dev;
struct uio *uio;
{
if (cn_tab == NULL)
return (0);
if (constty) /* 16 Aug 92*/
dev = constty->t_dev;
else
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_write)(dev, uio, flag));
}
cnioctl(dev, cmd, data, flag, p)
dev_t dev;
caddr_t data;
struct proc *p;
{
int error;
if (cn_tab == NULL)
return (0);
/*
* Superuser can always use this to wrest control of console
* output from the "virtual" console.
*/
if (cmd == TIOCCONS && constty) {
error = suser(p->p_ucred, (u_short *) NULL);
if (error)
return (error);
constty = NULL;
return (0);
}
dev = cn_tab->cn_dev;
return ((*cdevsw[major(dev)].d_ioctl)(dev, cmd, data, flag, p));
}
/*ARGSUSED*/
cnselect(dev, rw, p)
dev_t dev;
int rw;
struct proc *p;
{
if (cn_tab == NULL)
return (1);
return (ttselect(cn_tab->cn_dev, rw, p));
}
cngetc()
{
if (cn_tab == NULL)
return (0);
return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
}
cnputc(c)
register int c;
{
if (cn_tab == NULL)
return;
if (c) {
(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
if (c == '\n')
(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
}
}
pg(p,q,r,s,t,u,v,w,x,y,z) char *p; {
printf(p,q,r,s,t,u,v,w,x,y,z);
printf("\n>");
return(cngetc());
}