[apple/xnu.git] / bsd / kern / subr_log.c

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * 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.
 * 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.
 *
 *	@(#)subr_log.c	8.3 (Berkeley) 2/14/95
 */

/*
 * Error log buffer for kernel printf's.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc_internal.h>
#include <sys/vnode.h>
#include <sys/ioctl.h>
#include <sys/msgbuf.h>
#include <sys/file_internal.h>
#include <sys/errno.h>
#include <sys/select.h>
#include <sys/kernel.h>
#include <kern/thread.h>
#include <sys/lock.h>

#define LOG_RDPRI	(PZERO + 1)

#define LOG_NBIO	0x02
#define LOG_ASYNC	0x04
#define LOG_RDWAIT	0x08

struct logsoftc {
	int	sc_state;		/* see above for possibilities */
	struct	selinfo sc_selp;	/* thread waiting for select */
	int	sc_pgid;		/* process/group for async I/O */
} logsoftc;

int	log_open;			/* also used in log() */
struct msgbuf temp_msgbuf;
struct msgbuf *msgbufp;
static int _logentrypend = 0;
static int log_inited = 0;
void bsd_log_lock(void);
/* the following two are implemented in osfmk/kern/printf.c  */
extern void bsd_log_unlock(void);
extern void bsd_log_init(void);

/*
 * Serialize log access.  Note that the log can be written at interrupt level,
 * so any log manipulations that can be done from, or affect, another processor
 * at interrupt level must be guarded with a spin lock.
 */

#define	LOG_LOCK() bsd_log_lock()
#define	LOG_UNLOCK() bsd_log_unlock()


/*ARGSUSED*/
logopen(dev, flags, mode, p)
	dev_t dev;
	int flags, mode;
	struct proc *p;
{
	LOG_LOCK();
	if (log_open) {
		LOG_UNLOCK();
		return (EBUSY);
	}
	log_open = 1;
	logsoftc.sc_pgid = p->p_pid;		/* signal process only */
	/*
	 * Potential race here with putchar() but since putchar should be
	 * called by autoconf, msg_magic should be initialized by the time
	 * we get here.
	 */
	if (msgbufp->msg_magic != MSG_MAGIC) {
		register int i;

		msgbufp->msg_magic = MSG_MAGIC;
		msgbufp->msg_bufx = msgbufp->msg_bufr = 0;
		for (i=0; i < MSG_BSIZE; i++)
			msgbufp->msg_bufc[i] = 0;
	}
	LOG_UNLOCK();

	return (0);
}

/*ARGSUSED*/
int
logclose(dev, flag)
	dev_t dev;
{
	int oldpri;
	LOG_LOCK();
	log_open = 0;
	selwakeup(&logsoftc.sc_selp);
	selthreadclear(&logsoftc.sc_selp);
	LOG_UNLOCK();
	return (0);
}

/*ARGSUSED*/
int
logread(dev, uio, flag)
	dev_t dev;
	struct uio *uio;
	int flag;
{
	register long l;
	register int s;
	int error = 0;
	char localbuff[MSG_BSIZE];
	int copybytes;

	LOG_LOCK();
	while (msgbufp->msg_bufr == msgbufp->msg_bufx) {
		if (flag & IO_NDELAY) {
			error = EWOULDBLOCK;
			goto out;
		}
		if (logsoftc.sc_state & LOG_NBIO) {
			error = EWOULDBLOCK;
			goto out;
		}
		logsoftc.sc_state |= LOG_RDWAIT;
		LOG_UNLOCK();
		/*
		 * If the wakeup is missed the ligtening bolt will wake this up 
		 * if there are any new characters. If that doesn't do it
		 * then wait for 5 sec and reevaluate 
		 */
		if (error = tsleep((caddr_t)msgbufp, LOG_RDPRI | PCATCH,
				"klog", 5 * hz)) {
			/* if it times out; ignore */
			if (error != EWOULDBLOCK)
				return (error);
		}
		LOG_LOCK();
	}
	logsoftc.sc_state &= ~LOG_RDWAIT;


	while (uio_resid(uio) > 0) {
		l = msgbufp->msg_bufx - msgbufp->msg_bufr;
		if (l < 0)
			l = MSG_BSIZE - msgbufp->msg_bufr;
		l = min(l, uio_resid(uio));
		if (l == 0)
			break;
		bcopy(&msgbufp->msg_bufc[msgbufp->msg_bufr], &localbuff[0], l);
		LOG_UNLOCK();
		error = uiomove((caddr_t)&localbuff[0],
			(int)l, uio);
		LOG_LOCK();
		if (error)
			break;
		msgbufp->msg_bufr += l;
		if (msgbufp->msg_bufr < 0 || msgbufp->msg_bufr >= MSG_BSIZE)
			msgbufp->msg_bufr = 0;
	}
out:
	LOG_UNLOCK();
	return (error);
}

/*ARGSUSED*/
int
logselect(dev, rw, wql, p)
	dev_t dev;
	int rw;
	void * wql;
	struct proc *p;
{

	switch (rw) {

	case FREAD:
		LOG_LOCK();	
		if (msgbufp->msg_bufr != msgbufp->msg_bufx) {
			LOG_UNLOCK();
			return (1);
		}
		selrecord(p, &logsoftc.sc_selp, wql);
		LOG_UNLOCK();
		break;
	}
	return (0);
}

void
logwakeup()
{
	struct proc *p;
	int pgid;
	boolean_t funnel_state;

	LOG_LOCK();	
	if (!log_open) {
		LOG_UNLOCK();
		return;
	}
	selwakeup(&logsoftc.sc_selp);
	if (logsoftc.sc_state & LOG_ASYNC) {
		pgid = logsoftc.sc_pgid;
		LOG_UNLOCK();
		if (pgid < 0)
			gsignal(-pgid, SIGIO); 
		else if (p = pfind(pgid))
			psignal(p, SIGIO);
		LOG_LOCK();
	}
	if (logsoftc.sc_state & LOG_RDWAIT) {
		wakeup((caddr_t)msgbufp);
		logsoftc.sc_state &= ~LOG_RDWAIT;
	}
	LOG_UNLOCK();
}

void
klogwakeup()
{

	if (_logentrypend) {
		_logentrypend = 0;
		logwakeup();
	}
}

/*ARGSUSED*/
int
logioctl(dev, com, data, flag)
	caddr_t data;
{
	long l;
	int s;

	LOG_LOCK();	
	switch (com) {

	/* return number of characters immediately available */
	case FIONREAD:
		l = msgbufp->msg_bufx - msgbufp->msg_bufr;
		if (l < 0)
			l += MSG_BSIZE;
		*(off_t *)data = l;
		break;

	case FIONBIO:
		if (*(int *)data)
			logsoftc.sc_state |= LOG_NBIO;
		else
			logsoftc.sc_state &= ~LOG_NBIO;
		break;

	case FIOASYNC:
		if (*(int *)data)
			logsoftc.sc_state |= LOG_ASYNC;
		else
			logsoftc.sc_state &= ~LOG_ASYNC;
		break;

	case TIOCSPGRP:
		logsoftc.sc_pgid = *(int *)data;
		break;

	case TIOCGPGRP:
		*(int *)data = logsoftc.sc_pgid;
		break;

	default:
		LOG_UNLOCK();
		return (-1);
	}
	LOG_UNLOCK();
	return (0);
}

void
bsd_log_init()
{
	if (!log_inited) { 
		msgbufp = &temp_msgbuf;
		log_inited = 1;
	}
}

void
log_putc(char c)
{
	register struct msgbuf *mbp;

	if (!log_inited) {
		panic("bsd log is not inited");
	}
	LOG_LOCK();

	mbp = msgbufp; 
	if (mbp-> msg_magic != MSG_MAGIC) { 
		register int i;

		mbp->msg_magic = MSG_MAGIC;
		mbp->msg_bufx = mbp->msg_bufr = 0;
		for (i=0; i < MSG_BSIZE; i++)
			mbp->msg_bufc[i] = 0;
	}
	mbp->msg_bufc[mbp->msg_bufx++] = c;
	_logentrypend = 1;
	if (mbp->msg_bufx < 0 || mbp->msg_bufx >= MSG_BSIZE)
		mbp->msg_bufx = 0;
	LOG_UNLOCK();
}
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
1c79356b A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
37839358 A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
1c79356b	11	*
37839358 A	12	* This Original Code and all software distributed under the License are
37839358 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
37839358 A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
1c79356b A	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	23	/*
	24	* Copyright (c) 1982, 1986, 1993
	25	* The Regents of the University of California. All rights reserved.
	26	*
	27	* Redistribution and use in source and binary forms, with or without
	28	* modification, are permitted provided that the following conditions
	29	* are met:
	30	* 1. Redistributions of source code must retain the above copyright
	31	* notice, this list of conditions and the following disclaimer.
	32	* 2. Redistributions in binary form must reproduce the above copyright
	33	* notice, this list of conditions and the following disclaimer in the
	34	* documentation and/or other materials provided with the distribution.
	35	* 3. All advertising materials mentioning features or use of this software
	36	* must display the following acknowledgement:
	37	* This product includes software developed by the University of
	38	* California, Berkeley and its contributors.
	39	* 4. Neither the name of the University nor the names of its contributors
	40	* may be used to endorse or promote products derived from this software
	41	* without specific prior written permission.
	42	*
	43	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	44	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	45	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	46	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	47	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	48	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	49	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	50	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	51	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	52	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	53	* SUCH DAMAGE.
	54	*
	55	* @(#)subr_log.c 8.3 (Berkeley) 2/14/95
	56	*/
	57
	58	/*
	59	* Error log buffer for kernel printf's.
	60	*/
	61
	62	#include <sys/param.h>
	63	#include <sys/systm.h>
91447636	64	#include <sys/proc_internal.h>
1c79356b A	65	#include <sys/vnode.h>
	66	#include <sys/ioctl.h>
	67	#include <sys/msgbuf.h>
91447636	68	#include <sys/file_internal.h>
1c79356b A	69	#include <sys/errno.h>
1c79356b A	70	#include <sys/select.h>
91447636	71	#include <sys/kernel.h>
1c79356b	72	#include <kern/thread.h>
91447636	73	#include <sys/lock.h>
1c79356b A	74
	75	#define LOG_RDPRI (PZERO + 1)
	76
	77	#define LOG_NBIO 0x02
	78	#define LOG_ASYNC 0x04
	79	#define LOG_RDWAIT 0x08
	80
	81	struct logsoftc {
	82	int sc_state; /* see above for possibilities */
	83	struct selinfo sc_selp; /* thread waiting for select */
	84	int sc_pgid; /* process/group for async I/O */
	85	} logsoftc;
	86
	87	int log_open; /* also used in log() */
	88	struct msgbuf temp_msgbuf;
	89	struct msgbuf *msgbufp;
	90	static int _logentrypend = 0;
91447636 A	91	static int log_inited = 0;
	92	void bsd_log_lock(void);
	93	/* the following two are implemented in osfmk/kern/printf.c */
	94	extern void bsd_log_unlock(void);
	95	extern void bsd_log_init(void);
1c79356b A	96
	97	/*
	98	* Serialize log access. Note that the log can be written at interrupt level,
	99	* so any log manipulations that can be done from, or affect, another processor
	100	* at interrupt level must be guarded with a spin lock.
	101	*/
91447636 A	102
	103	#define LOG_LOCK() bsd_log_lock()
	104	#define LOG_UNLOCK() bsd_log_unlock()
	105
1c79356b A	106
	107	/ARGSUSED/
	108	logopen(dev, flags, mode, p)
	109	dev_t dev;
	110	int flags, mode;
	111	struct proc *p;
	112	{
1c79356b A	113	LOG_LOCK();
	114	if (log_open) {
	115	LOG_UNLOCK();
1c79356b A	116	return (EBUSY);
	117	}
	118	log_open = 1;
	119	logsoftc.sc_pgid = p->p_pid; /* signal process only */
	120	/*
	121	* Potential race here with putchar() but since putchar should be
	122	* called by autoconf, msg_magic should be initialized by the time
	123	* we get here.
	124	*/
	125	if (msgbufp->msg_magic != MSG_MAGIC) {
	126	register int i;
	127
	128	msgbufp->msg_magic = MSG_MAGIC;
	129	msgbufp->msg_bufx = msgbufp->msg_bufr = 0;
	130	for (i=0; i < MSG_BSIZE; i++)
	131	msgbufp->msg_bufc[i] = 0;
	132	}
	133	LOG_UNLOCK();
9bccf70c	134
1c79356b A	135	return (0);
	136	}
	137
	138	/ARGSUSED/
	139	int
	140	logclose(dev, flag)
	141	dev_t dev;
	142	{
	143	int oldpri;
	144	LOG_LOCK();
	145	log_open = 0;
	146	selwakeup(&logsoftc.sc_selp);
1c79356b	147	selthreadclear(&logsoftc.sc_selp);
1c79356b A	148	LOG_UNLOCK();
	149	return (0);
	150	}
	151
	152	/ARGSUSED/
	153	int
	154	logread(dev, uio, flag)
	155	dev_t dev;
	156	struct uio *uio;
	157	int flag;
	158	{
	159	register long l;
	160	register int s;
	161	int error = 0;
91447636 A	162	char localbuff[MSG_BSIZE];
91447636 A	163	int copybytes;
1c79356b	164
91447636	165	LOG_LOCK();
1c79356b A	166	while (msgbufp->msg_bufr == msgbufp->msg_bufx) {
1c79356b A	167	if (flag & IO_NDELAY) {
91447636 A	168	error = EWOULDBLOCK;
91447636 A	169	goto out;
1c79356b A	170	}
1c79356b A	171	if (logsoftc.sc_state & LOG_NBIO) {
91447636 A	172	error = EWOULDBLOCK;
91447636 A	173	goto out;
1c79356b A	174	}
1c79356b A	175	logsoftc.sc_state \|= LOG_RDWAIT;
91447636 A	176	LOG_UNLOCK();
	177	/*
	178	* If the wakeup is missed the ligtening bolt will wake this up
	179	* if there are any new characters. If that doesn't do it
	180	* then wait for 5 sec and reevaluate
	181	*/
1c79356b	182	if (error = tsleep((caddr_t)msgbufp, LOG_RDPRI \| PCATCH,
91447636 A	183	"klog", 5 * hz)) {
	184	/* if it times out; ignore */
	185	if (error != EWOULDBLOCK)
	186	return (error);
1c79356b	187	}
91447636	188	LOG_LOCK();
1c79356b	189	}
1c79356b A	190	logsoftc.sc_state &= ~LOG_RDWAIT;
1c79356b A	191
91447636 A	192
91447636 A	193	while (uio_resid(uio) > 0) {
1c79356b A	194	l = msgbufp->msg_bufx - msgbufp->msg_bufr;
	195	if (l < 0)
	196	l = MSG_BSIZE - msgbufp->msg_bufr;
91447636	197	l = min(l, uio_resid(uio));
1c79356b A	198	if (l == 0)
1c79356b A	199	break;
91447636 A	200	bcopy(&msgbufp->msg_bufc[msgbufp->msg_bufr], &localbuff[0], l);
	201	LOG_UNLOCK();
	202	error = uiomove((caddr_t)&localbuff[0],
1c79356b	203	(int)l, uio);
91447636	204	LOG_LOCK();
1c79356b A	205	if (error)
	206	break;
	207	msgbufp->msg_bufr += l;
	208	if (msgbufp->msg_bufr < 0 \|\| msgbufp->msg_bufr >= MSG_BSIZE)
	209	msgbufp->msg_bufr = 0;
	210	}
91447636 A	211	out:
91447636 A	212	LOG_UNLOCK();
1c79356b A	213	return (error);
	214	}
	215
	216	/ARGSUSED/
	217	int
0b4e3aa0	218	logselect(dev, rw, wql, p)
1c79356b A	219	dev_t dev;
1c79356b A	220	int rw;
0b4e3aa0	221	void * wql;
1c79356b A	222	struct proc *p;
1c79356b A	223	{
1c79356b A	224
	225	switch (rw) {
	226
	227	case FREAD:
91447636	228	LOG_LOCK();
1c79356b	229	if (msgbufp->msg_bufr != msgbufp->msg_bufx) {
91447636	230	LOG_UNLOCK();
1c79356b A	231	return (1);
1c79356b A	232	}
0b4e3aa0	233	selrecord(p, &logsoftc.sc_selp, wql);
91447636	234	LOG_UNLOCK();
1c79356b A	235	break;
1c79356b A	236	}
1c79356b A	237	return (0);
	238	}
	239
	240	void
	241	logwakeup()
	242	{
	243	struct proc *p;
	244	int pgid;
	245	boolean_t funnel_state;
	246
91447636 A	247	LOG_LOCK();
	248	if (!log_open) {
	249	LOG_UNLOCK();
1c79356b	250	return;
91447636	251	}
1c79356b A	252	selwakeup(&logsoftc.sc_selp);
1c79356b A	253	if (logsoftc.sc_state & LOG_ASYNC) {
1c79356b A	254	pgid = logsoftc.sc_pgid;
	255	LOG_UNLOCK();
	256	if (pgid < 0)
	257	gsignal(-pgid, SIGIO);
	258	else if (p = pfind(pgid))
	259	psignal(p, SIGIO);
91447636	260	LOG_LOCK();
1c79356b A	261	}
	262	if (logsoftc.sc_state & LOG_RDWAIT) {
	263	wakeup((caddr_t)msgbufp);
	264	logsoftc.sc_state &= ~LOG_RDWAIT;
	265	}
91447636	266	LOG_UNLOCK();
1c79356b A	267	}
	268
	269	void
	270	klogwakeup()
	271	{
	272
	273	if (_logentrypend) {
	274	_logentrypend = 0;
	275	logwakeup();
	276	}
	277	}
	278
	279	/ARGSUSED/
	280	int
55e303ae	281	logioctl(dev, com, data, flag)
1c79356b A	282	caddr_t data;
	283	{
	284	long l;
	285	int s;
	286
91447636	287	LOG_LOCK();
1c79356b A	288	switch (com) {
	289
	290	/* return number of characters immediately available */
	291	case FIONREAD:
1c79356b	292	l = msgbufp->msg_bufx - msgbufp->msg_bufr;
1c79356b A	293	if (l < 0)
	294	l += MSG_BSIZE;
	295	(off_t )data = l;
	296	break;
	297
	298	case FIONBIO:
	299	if ((int )data)
	300	logsoftc.sc_state \|= LOG_NBIO;
	301	else
	302	logsoftc.sc_state &= ~LOG_NBIO;
	303	break;
	304
	305	case FIOASYNC:
	306	if ((int )data)
	307	logsoftc.sc_state \|= LOG_ASYNC;
	308	else
	309	logsoftc.sc_state &= ~LOG_ASYNC;
	310	break;
	311
	312	case TIOCSPGRP:
1c79356b	313	logsoftc.sc_pgid = (int )data;
1c79356b A	314	break;
	315
	316	case TIOCGPGRP:
1c79356b	317	(int )data = logsoftc.sc_pgid;
1c79356b A	318	break;
	319
	320	default:
91447636	321	LOG_UNLOCK();
1c79356b A	322	return (-1);
1c79356b A	323	}
91447636	324	LOG_UNLOCK();
1c79356b A	325	return (0);
	326	}
	327
	328	void
91447636	329	bsd_log_init()
1c79356b	330	{
91447636 A	331	if (!log_inited) {
	332	msgbufp = &temp_msgbuf;
	333	log_inited = 1;
	334	}
1c79356b A	335	}
	336
	337	void
	338	log_putc(char c)
	339	{
	340	register struct msgbuf *mbp;
	341
91447636 A	342	if (!log_inited) {
	343	panic("bsd log is not inited");
	344	}
	345	LOG_LOCK();
1c79356b A	346
	347	mbp = msgbufp;
	348	if (mbp-> msg_magic != MSG_MAGIC) {
	349	register int i;
	350
	351	mbp->msg_magic = MSG_MAGIC;
	352	mbp->msg_bufx = mbp->msg_bufr = 0;
	353	for (i=0; i < MSG_BSIZE; i++)
	354	mbp->msg_bufc[i] = 0;
	355	}
	356	mbp->msg_bufc[mbp->msg_bufx++] = c;
	357	_logentrypend = 1;
	358	if (mbp->msg_bufx < 0 \|\| mbp->msg_bufx >= MSG_BSIZE)
	359	mbp->msg_bufx = 0;
91447636	360	LOG_UNLOCK();
1c79356b	361	}
91447636	362