256 lines
6.3 KiB
C
256 lines
6.3 KiB
C
/*
|
|
* Copyright (c) 1982, 1986, 1993
|
|
* 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.
|
|
* 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.
|
|
*
|
|
* @(#)subr_log.c 8.1 (Berkeley) 6/10/93
|
|
*/
|
|
|
|
/*
|
|
* Error log buffer for kernel printf's.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/conf.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/vnode.h>
|
|
#include <sys/filio.h>
|
|
#include <sys/ttycom.h>
|
|
#include <sys/msgbuf.h>
|
|
#include <sys/signalvar.h>
|
|
#include <sys/kernel.h>
|
|
#include <sys/poll.h>
|
|
#include <sys/filedesc.h>
|
|
#include <sys/sysctl.h>
|
|
|
|
#define LOG_RDPRI (PZERO + 1)
|
|
|
|
#define LOG_ASYNC 0x04
|
|
#define LOG_RDWAIT 0x08
|
|
|
|
static d_open_t logopen;
|
|
static d_close_t logclose;
|
|
static d_read_t logread;
|
|
static d_ioctl_t logioctl;
|
|
static d_poll_t logpoll;
|
|
|
|
static void logtimeout(void *arg);
|
|
|
|
#define CDEV_MAJOR 7
|
|
static struct cdevsw log_cdevsw = {
|
|
.d_version = D_VERSION,
|
|
.d_flags = D_NEEDGIANT,
|
|
.d_open = logopen,
|
|
.d_close = logclose,
|
|
.d_read = logread,
|
|
.d_ioctl = logioctl,
|
|
.d_poll = logpoll,
|
|
.d_name = "log",
|
|
.d_maj = CDEV_MAJOR,
|
|
};
|
|
|
|
static struct logsoftc {
|
|
int sc_state; /* see above for possibilities */
|
|
struct selinfo sc_selp; /* process waiting on select call */
|
|
struct sigio *sc_sigio; /* information for async I/O */
|
|
struct callout sc_callout; /* callout to wakeup syslog */
|
|
} logsoftc;
|
|
|
|
int log_open; /* also used in log() */
|
|
|
|
/* Times per second to check for a pending syslog wakeup. */
|
|
static int log_wakeups_per_second = 5;
|
|
SYSCTL_INT(_kern, OID_AUTO, log_wakeups_per_second, CTLFLAG_RW,
|
|
&log_wakeups_per_second, 0, "");
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
logopen(struct cdev *dev, int flags, int mode, struct thread *td)
|
|
{
|
|
if (log_open)
|
|
return (EBUSY);
|
|
log_open = 1;
|
|
callout_init(&logsoftc.sc_callout, 0);
|
|
fsetown(td->td_proc->p_pid, &logsoftc.sc_sigio); /* signal process only */
|
|
if (log_wakeups_per_second < 1) {
|
|
printf("syslog wakeup is less than one. Adjusting to 1.\n");
|
|
log_wakeups_per_second = 1;
|
|
}
|
|
callout_reset(&logsoftc.sc_callout, hz / log_wakeups_per_second,
|
|
logtimeout, NULL);
|
|
return (0);
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
logclose(struct cdev *dev, int flag, int mode, struct thread *td)
|
|
{
|
|
|
|
log_open = 0;
|
|
callout_stop(&logsoftc.sc_callout);
|
|
logsoftc.sc_state = 0;
|
|
funsetown(&logsoftc.sc_sigio);
|
|
return (0);
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
logread(struct cdev *dev, struct uio *uio, int flag)
|
|
{
|
|
char buf[128];
|
|
struct msgbuf *mbp = msgbufp;
|
|
int error = 0, l, s;
|
|
|
|
s = splhigh();
|
|
while (msgbuf_getcount(mbp) == 0) {
|
|
if (flag & IO_NDELAY) {
|
|
splx(s);
|
|
return (EWOULDBLOCK);
|
|
}
|
|
logsoftc.sc_state |= LOG_RDWAIT;
|
|
if ((error = tsleep(mbp, LOG_RDPRI | PCATCH, "klog", 0))) {
|
|
splx(s);
|
|
return (error);
|
|
}
|
|
}
|
|
splx(s);
|
|
logsoftc.sc_state &= ~LOG_RDWAIT;
|
|
|
|
while (uio->uio_resid > 0) {
|
|
l = imin(sizeof(buf), uio->uio_resid);
|
|
l = msgbuf_getbytes(mbp, buf, l);
|
|
if (l == 0)
|
|
break;
|
|
error = uiomove(buf, l, uio);
|
|
if (error)
|
|
break;
|
|
}
|
|
return (error);
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
logpoll(struct cdev *dev, int events, struct thread *td)
|
|
{
|
|
int s;
|
|
int revents = 0;
|
|
|
|
s = splhigh();
|
|
|
|
if (events & (POLLIN | POLLRDNORM)) {
|
|
if (msgbuf_getcount(msgbufp) > 0)
|
|
revents |= events & (POLLIN | POLLRDNORM);
|
|
else
|
|
selrecord(td, &logsoftc.sc_selp);
|
|
}
|
|
splx(s);
|
|
return (revents);
|
|
}
|
|
|
|
static void
|
|
logtimeout(void *arg)
|
|
{
|
|
|
|
if (!log_open)
|
|
return;
|
|
if (log_wakeups_per_second < 1) {
|
|
printf("syslog wakeup is less than one. Adjusting to 1.\n");
|
|
log_wakeups_per_second = 1;
|
|
}
|
|
if (msgbuftrigger == 0) {
|
|
callout_reset(&logsoftc.sc_callout,
|
|
hz / log_wakeups_per_second, logtimeout, NULL);
|
|
return;
|
|
}
|
|
msgbuftrigger = 0;
|
|
selwakeuppri(&logsoftc.sc_selp, LOG_RDPRI);
|
|
if ((logsoftc.sc_state & LOG_ASYNC) && logsoftc.sc_sigio != NULL)
|
|
pgsigio(&logsoftc.sc_sigio, SIGIO, 0);
|
|
if (logsoftc.sc_state & LOG_RDWAIT) {
|
|
wakeup(msgbufp);
|
|
logsoftc.sc_state &= ~LOG_RDWAIT;
|
|
}
|
|
callout_reset(&logsoftc.sc_callout, hz / log_wakeups_per_second,
|
|
logtimeout, NULL);
|
|
}
|
|
|
|
/*ARGSUSED*/
|
|
static int
|
|
logioctl(struct cdev *dev, u_long com, caddr_t data, int flag, struct thread *td)
|
|
{
|
|
|
|
switch (com) {
|
|
|
|
/* return number of characters immediately available */
|
|
case FIONREAD:
|
|
*(int *)data = msgbuf_getcount(msgbufp);
|
|
break;
|
|
|
|
case FIONBIO:
|
|
break;
|
|
|
|
case FIOASYNC:
|
|
if (*(int *)data)
|
|
logsoftc.sc_state |= LOG_ASYNC;
|
|
else
|
|
logsoftc.sc_state &= ~LOG_ASYNC;
|
|
break;
|
|
|
|
case FIOSETOWN:
|
|
return (fsetown(*(int *)data, &logsoftc.sc_sigio));
|
|
|
|
case FIOGETOWN:
|
|
*(int *)data = fgetown(&logsoftc.sc_sigio);
|
|
break;
|
|
|
|
/* This is deprecated, FIOSETOWN should be used instead. */
|
|
case TIOCSPGRP:
|
|
return (fsetown(-(*(int *)data), &logsoftc.sc_sigio));
|
|
|
|
/* This is deprecated, FIOGETOWN should be used instead */
|
|
case TIOCGPGRP:
|
|
*(int *)data = -fgetown(&logsoftc.sc_sigio);
|
|
break;
|
|
|
|
default:
|
|
return (ENOTTY);
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
log_drvinit(void *unused)
|
|
{
|
|
|
|
make_dev(&log_cdevsw, 0, UID_ROOT, GID_WHEEL, 0600, "klog");
|
|
}
|
|
|
|
SYSINIT(logdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,log_drvinit,NULL)
|