subr_log.c revision 47625
11541Srgrimes/* 21541Srgrimes * Copyright (c) 1982, 1986, 1993 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * 51541Srgrimes * Redistribution and use in source and binary forms, with or without 61541Srgrimes * modification, are permitted provided that the following conditions 71541Srgrimes * are met: 81541Srgrimes * 1. Redistributions of source code must retain the above copyright 91541Srgrimes * notice, this list of conditions and the following disclaimer. 101541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 111541Srgrimes * notice, this list of conditions and the following disclaimer in the 121541Srgrimes * documentation and/or other materials provided with the distribution. 131541Srgrimes * 3. All advertising materials mentioning features or use of this software 141541Srgrimes * must display the following acknowledgement: 151541Srgrimes * This product includes software developed by the University of 161541Srgrimes * California, Berkeley and its contributors. 171541Srgrimes * 4. Neither the name of the University nor the names of its contributors 181541Srgrimes * may be used to endorse or promote products derived from this software 191541Srgrimes * without specific prior written permission. 201541Srgrimes * 211541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 221541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 231541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 241541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 251541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 261541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 271541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 281541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 291541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 301541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 311541Srgrimes * SUCH DAMAGE. 321541Srgrimes * 331541Srgrimes * @(#)subr_log.c 8.1 (Berkeley) 6/10/93 3447625Sphk * $Id: subr_log.c,v 1.34 1999/05/06 18:12:46 peter Exp $ 351541Srgrimes */ 361541Srgrimes 371541Srgrimes/* 381541Srgrimes * Error log buffer for kernel printf's. 391541Srgrimes */ 401541Srgrimes 4132726Seivind#include "opt_devfs.h" 4232726Seivind 431541Srgrimes#include <sys/param.h> 441541Srgrimes#include <sys/systm.h> 4512577Sbde#include <sys/conf.h> 461541Srgrimes#include <sys/proc.h> 471541Srgrimes#include <sys/vnode.h> 4824206Sbde#include <sys/filio.h> 4924206Sbde#include <sys/ttycom.h> 501541Srgrimes#include <sys/msgbuf.h> 513308Sphk#include <sys/signalvar.h> 5212517Sjulian#include <sys/kernel.h> 5329357Speter#include <sys/poll.h> 5441086Struckman#include <sys/filedesc.h> 5512517Sjulian#ifdef DEVFS 5612517Sjulian#include <sys/devfsext.h> 5712517Sjulian#endif /*DEVFS*/ 5812517Sjulian 591541Srgrimes#define LOG_RDPRI (PZERO + 1) 601541Srgrimes 611541Srgrimes#define LOG_ASYNC 0x04 621541Srgrimes#define LOG_RDWAIT 0x08 631541Srgrimes 6412675Sjulianstatic d_open_t logopen; 6512675Sjulianstatic d_close_t logclose; 6612675Sjulianstatic d_read_t logread; 6712675Sjulianstatic d_ioctl_t logioctl; 6829357Speterstatic d_poll_t logpoll; 6912675Sjulian 7012675Sjulian#define CDEV_MAJOR 7 7147625Sphkstatic struct cdevsw log_cdevsw = { 7247625Sphk /* open */ logopen, 7347625Sphk /* close */ logclose, 7447625Sphk /* read */ logread, 7547625Sphk /* write */ nowrite, 7647625Sphk /* ioctl */ logioctl, 7747625Sphk /* stop */ nostop, 7847625Sphk /* reset */ noreset, 7947625Sphk /* devtotty */ nodevtotty, 8047625Sphk /* poll */ logpoll, 8147625Sphk /* mmap */ nommap, 8247625Sphk /* strategy */ nostrategy, 8347625Sphk /* name */ "log", 8447625Sphk /* parms */ noparms, 8547625Sphk /* maj */ CDEV_MAJOR, 8647625Sphk /* dump */ nodump, 8747625Sphk /* psize */ nopsize, 8847625Sphk /* flags */ 0, 8947625Sphk /* maxio */ 0, 9047625Sphk /* bmaj */ -1 9147625Sphk}; 9212675Sjulian 9312819Sphkstatic struct logsoftc { 941541Srgrimes int sc_state; /* see above for possibilities */ 951541Srgrimes struct selinfo sc_selp; /* process waiting on select call */ 9641087Struckman struct sigio *sc_sigio; /* information for async I/O */ 971541Srgrimes} logsoftc; 981541Srgrimes 991541Srgrimesint log_open; /* also used in log() */ 1001541Srgrimes 1011541Srgrimes/*ARGSUSED*/ 10212675Sjulianstatic int 1031541Srgrimeslogopen(dev, flags, mode, p) 1041541Srgrimes dev_t dev; 1051541Srgrimes int flags, mode; 1061541Srgrimes struct proc *p; 1071541Srgrimes{ 1081541Srgrimes if (log_open) 1091541Srgrimes return (EBUSY); 1101541Srgrimes log_open = 1; 11141086Struckman fsetown(p->p_pid, &logsoftc.sc_sigio); /* signal process only */ 1121541Srgrimes return (0); 1131541Srgrimes} 1141541Srgrimes 1151541Srgrimes/*ARGSUSED*/ 11612675Sjulianstatic int 1171541Srgrimeslogclose(dev, flag, mode, p) 1181541Srgrimes dev_t dev; 1191541Srgrimes int flag, mode; 1201541Srgrimes struct proc *p; 1211541Srgrimes{ 1221541Srgrimes 1231541Srgrimes log_open = 0; 1241541Srgrimes logsoftc.sc_state = 0; 12541086Struckman funsetown(logsoftc.sc_sigio); 1261541Srgrimes return (0); 1271541Srgrimes} 1281541Srgrimes 1291541Srgrimes/*ARGSUSED*/ 13012675Sjulianstatic int 1311541Srgrimeslogread(dev, uio, flag) 1321541Srgrimes dev_t dev; 1331541Srgrimes struct uio *uio; 1341541Srgrimes int flag; 1351541Srgrimes{ 1361541Srgrimes register struct msgbuf *mbp = msgbufp; 1371541Srgrimes register long l; 1381541Srgrimes register int s; 1391541Srgrimes int error = 0; 1401541Srgrimes 1411541Srgrimes s = splhigh(); 1421541Srgrimes while (mbp->msg_bufr == mbp->msg_bufx) { 1431541Srgrimes if (flag & IO_NDELAY) { 1441541Srgrimes splx(s); 1451541Srgrimes return (EWOULDBLOCK); 1461541Srgrimes } 1471541Srgrimes logsoftc.sc_state |= LOG_RDWAIT; 1483098Sphk if ((error = tsleep((caddr_t)mbp, LOG_RDPRI | PCATCH, 1493098Sphk "klog", 0))) { 1501541Srgrimes splx(s); 1511541Srgrimes return (error); 1521541Srgrimes } 1531541Srgrimes } 1541541Srgrimes splx(s); 1551541Srgrimes logsoftc.sc_state &= ~LOG_RDWAIT; 1561541Srgrimes 1571541Srgrimes while (uio->uio_resid > 0) { 1581541Srgrimes l = mbp->msg_bufx - mbp->msg_bufr; 1591541Srgrimes if (l < 0) 16036179Sphk l = mbp->msg_size - mbp->msg_bufr; 1611541Srgrimes l = min(l, uio->uio_resid); 1621541Srgrimes if (l == 0) 1631541Srgrimes break; 16436179Sphk error = uiomove((caddr_t)msgbufp->msg_ptr + mbp->msg_bufr, 16536179Sphk (int)l, uio); 1661541Srgrimes if (error) 1671541Srgrimes break; 1681541Srgrimes mbp->msg_bufr += l; 16936179Sphk if (mbp->msg_bufr >= mbp->msg_size) 1701541Srgrimes mbp->msg_bufr = 0; 1711541Srgrimes } 1721541Srgrimes return (error); 1731541Srgrimes} 1741541Srgrimes 1751541Srgrimes/*ARGSUSED*/ 17612675Sjulianstatic int 17729357Speterlogpoll(dev, events, p) 1781541Srgrimes dev_t dev; 17929357Speter int events; 1801541Srgrimes struct proc *p; 1811541Srgrimes{ 18229357Speter int s; 18329357Speter int revents = 0; 1841541Srgrimes 18529357Speter s = splhigh(); 1861541Srgrimes 18746568Speter if (events & (POLLIN | POLLRDNORM)) { 18829357Speter if (msgbufp->msg_bufr != msgbufp->msg_bufx) 18929357Speter revents |= events & (POLLIN | POLLRDNORM); 19029357Speter else 19129357Speter selrecord(p, &logsoftc.sc_selp); 19246568Speter } 1931541Srgrimes splx(s); 19429357Speter return (revents); 1951541Srgrimes} 1961541Srgrimes 1971549Srgrimesvoid 1981541Srgrimeslogwakeup() 1991541Srgrimes{ 2001541Srgrimes if (!log_open) 2011541Srgrimes return; 2021541Srgrimes selwakeup(&logsoftc.sc_selp); 20341086Struckman if ((logsoftc.sc_state & LOG_ASYNC) && logsoftc.sc_sigio != NULL) 20441086Struckman pgsigio(logsoftc.sc_sigio, SIGIO, 0); 2051541Srgrimes if (logsoftc.sc_state & LOG_RDWAIT) { 2061541Srgrimes wakeup((caddr_t)msgbufp); 2071541Srgrimes logsoftc.sc_state &= ~LOG_RDWAIT; 2081541Srgrimes } 2091541Srgrimes} 2101541Srgrimes 2111541Srgrimes/*ARGSUSED*/ 21212675Sjulianstatic int 2131541Srgrimeslogioctl(dev, com, data, flag, p) 2141541Srgrimes dev_t dev; 21536735Sdfr u_long com; 2161541Srgrimes caddr_t data; 2171541Srgrimes int flag; 2181541Srgrimes struct proc *p; 2191541Srgrimes{ 2201541Srgrimes long l; 2211541Srgrimes int s; 2221541Srgrimes 2231541Srgrimes switch (com) { 2241541Srgrimes 2251541Srgrimes /* return number of characters immediately available */ 2261541Srgrimes case FIONREAD: 2271541Srgrimes s = splhigh(); 2281541Srgrimes l = msgbufp->msg_bufx - msgbufp->msg_bufr; 2291541Srgrimes splx(s); 2301541Srgrimes if (l < 0) 23136179Sphk l += msgbufp->msg_size; 2321541Srgrimes *(int *)data = l; 2331541Srgrimes break; 2341541Srgrimes 2351541Srgrimes case FIONBIO: 2361541Srgrimes break; 2371541Srgrimes 2381541Srgrimes case FIOASYNC: 2391541Srgrimes if (*(int *)data) 2401541Srgrimes logsoftc.sc_state |= LOG_ASYNC; 2411541Srgrimes else 2421541Srgrimes logsoftc.sc_state &= ~LOG_ASYNC; 2431541Srgrimes break; 2441541Srgrimes 24541086Struckman case FIOSETOWN: 24641086Struckman return (fsetown(*(int *)data, &logsoftc.sc_sigio)); 24741086Struckman 24841086Struckman case FIOGETOWN: 24941086Struckman *(int *)data = fgetown(logsoftc.sc_sigio); 2501541Srgrimes break; 2511541Srgrimes 25241086Struckman /* This is deprecated, FIOSETOWN should be used instead. */ 25341086Struckman case TIOCSPGRP: 25441086Struckman return (fsetown(-(*(int *)data), &logsoftc.sc_sigio)); 25541086Struckman 25641086Struckman /* This is deprecated, FIOGETOWN should be used instead */ 2571541Srgrimes case TIOCGPGRP: 25841086Struckman *(int *)data = -fgetown(logsoftc.sc_sigio); 2591541Srgrimes break; 2601541Srgrimes 2611541Srgrimes default: 2628161Sjkh return (ENOTTY); 2631541Srgrimes } 2641541Srgrimes return (0); 2651541Srgrimes} 26612517Sjulian 26733679Sbdestatic int log_devsw_installed; 26817040Swollman#ifdef DEVFS 26912675Sjulianstatic void *log_devfs_token; 27017040Swollman#endif 27112517Sjulian 27229506Sbdestatic void log_drvinit __P((void *unused)); 27312675Sjulianstatic void 27429506Sbdelog_drvinit(unused) 27529506Sbde void *unused; 27612517Sjulian{ 27712517Sjulian dev_t dev; 27812517Sjulian 27912517Sjulian if( ! log_devsw_installed ) { 28012517Sjulian dev = makedev(CDEV_MAJOR,0); 28112517Sjulian cdevsw_add(&dev,&log_cdevsw,NULL); 28212517Sjulian log_devsw_installed = 1; 28312517Sjulian#ifdef DEVFS 28414851Sbde log_devfs_token = devfs_add_devswf(&log_cdevsw, 0, DV_CHR, 28514851Sbde UID_ROOT, GID_WHEEL, 0600, 28614851Sbde "klog"); 28712521Sjulian#endif 28812517Sjulian } 28912517Sjulian} 29012517Sjulian 29112517SjulianSYSINIT(logdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,log_drvinit,NULL) 292