subr_log.c revision 46568
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 3446568Speter * $Id: subr_log.c,v 1.33 1998/12/07 21:58:29 archie 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 7112678Sphkstatic struct cdevsw log_cdevsw = 7212675Sjulian { logopen, logclose, logread, nowrite, /*7*/ 7312675Sjulian logioctl, nostop, nullreset, nodevtotty,/* klog */ 7429357Speter logpoll, nommap, NULL, "log", NULL, -1 }; 7512675Sjulian 7612819Sphkstatic struct logsoftc { 771541Srgrimes int sc_state; /* see above for possibilities */ 781541Srgrimes struct selinfo sc_selp; /* process waiting on select call */ 7941087Struckman struct sigio *sc_sigio; /* information for async I/O */ 801541Srgrimes} logsoftc; 811541Srgrimes 821541Srgrimesint log_open; /* also used in log() */ 831541Srgrimes 841541Srgrimes/*ARGSUSED*/ 8512675Sjulianstatic int 861541Srgrimeslogopen(dev, flags, mode, p) 871541Srgrimes dev_t dev; 881541Srgrimes int flags, mode; 891541Srgrimes struct proc *p; 901541Srgrimes{ 911541Srgrimes if (log_open) 921541Srgrimes return (EBUSY); 931541Srgrimes log_open = 1; 9441086Struckman fsetown(p->p_pid, &logsoftc.sc_sigio); /* signal process only */ 951541Srgrimes return (0); 961541Srgrimes} 971541Srgrimes 981541Srgrimes/*ARGSUSED*/ 9912675Sjulianstatic int 1001541Srgrimeslogclose(dev, flag, mode, p) 1011541Srgrimes dev_t dev; 1021541Srgrimes int flag, mode; 1031541Srgrimes struct proc *p; 1041541Srgrimes{ 1051541Srgrimes 1061541Srgrimes log_open = 0; 1071541Srgrimes logsoftc.sc_state = 0; 10841086Struckman funsetown(logsoftc.sc_sigio); 1091541Srgrimes return (0); 1101541Srgrimes} 1111541Srgrimes 1121541Srgrimes/*ARGSUSED*/ 11312675Sjulianstatic int 1141541Srgrimeslogread(dev, uio, flag) 1151541Srgrimes dev_t dev; 1161541Srgrimes struct uio *uio; 1171541Srgrimes int flag; 1181541Srgrimes{ 1191541Srgrimes register struct msgbuf *mbp = msgbufp; 1201541Srgrimes register long l; 1211541Srgrimes register int s; 1221541Srgrimes int error = 0; 1231541Srgrimes 1241541Srgrimes s = splhigh(); 1251541Srgrimes while (mbp->msg_bufr == mbp->msg_bufx) { 1261541Srgrimes if (flag & IO_NDELAY) { 1271541Srgrimes splx(s); 1281541Srgrimes return (EWOULDBLOCK); 1291541Srgrimes } 1301541Srgrimes logsoftc.sc_state |= LOG_RDWAIT; 1313098Sphk if ((error = tsleep((caddr_t)mbp, LOG_RDPRI | PCATCH, 1323098Sphk "klog", 0))) { 1331541Srgrimes splx(s); 1341541Srgrimes return (error); 1351541Srgrimes } 1361541Srgrimes } 1371541Srgrimes splx(s); 1381541Srgrimes logsoftc.sc_state &= ~LOG_RDWAIT; 1391541Srgrimes 1401541Srgrimes while (uio->uio_resid > 0) { 1411541Srgrimes l = mbp->msg_bufx - mbp->msg_bufr; 1421541Srgrimes if (l < 0) 14336179Sphk l = mbp->msg_size - mbp->msg_bufr; 1441541Srgrimes l = min(l, uio->uio_resid); 1451541Srgrimes if (l == 0) 1461541Srgrimes break; 14736179Sphk error = uiomove((caddr_t)msgbufp->msg_ptr + mbp->msg_bufr, 14836179Sphk (int)l, uio); 1491541Srgrimes if (error) 1501541Srgrimes break; 1511541Srgrimes mbp->msg_bufr += l; 15236179Sphk if (mbp->msg_bufr >= mbp->msg_size) 1531541Srgrimes mbp->msg_bufr = 0; 1541541Srgrimes } 1551541Srgrimes return (error); 1561541Srgrimes} 1571541Srgrimes 1581541Srgrimes/*ARGSUSED*/ 15912675Sjulianstatic int 16029357Speterlogpoll(dev, events, p) 1611541Srgrimes dev_t dev; 16229357Speter int events; 1631541Srgrimes struct proc *p; 1641541Srgrimes{ 16529357Speter int s; 16629357Speter int revents = 0; 1671541Srgrimes 16829357Speter s = splhigh(); 1691541Srgrimes 17046568Speter if (events & (POLLIN | POLLRDNORM)) { 17129357Speter if (msgbufp->msg_bufr != msgbufp->msg_bufx) 17229357Speter revents |= events & (POLLIN | POLLRDNORM); 17329357Speter else 17429357Speter selrecord(p, &logsoftc.sc_selp); 17546568Speter } 1761541Srgrimes splx(s); 17729357Speter return (revents); 1781541Srgrimes} 1791541Srgrimes 1801549Srgrimesvoid 1811541Srgrimeslogwakeup() 1821541Srgrimes{ 1831541Srgrimes if (!log_open) 1841541Srgrimes return; 1851541Srgrimes selwakeup(&logsoftc.sc_selp); 18641086Struckman if ((logsoftc.sc_state & LOG_ASYNC) && logsoftc.sc_sigio != NULL) 18741086Struckman pgsigio(logsoftc.sc_sigio, SIGIO, 0); 1881541Srgrimes if (logsoftc.sc_state & LOG_RDWAIT) { 1891541Srgrimes wakeup((caddr_t)msgbufp); 1901541Srgrimes logsoftc.sc_state &= ~LOG_RDWAIT; 1911541Srgrimes } 1921541Srgrimes} 1931541Srgrimes 1941541Srgrimes/*ARGSUSED*/ 19512675Sjulianstatic int 1961541Srgrimeslogioctl(dev, com, data, flag, p) 1971541Srgrimes dev_t dev; 19836735Sdfr u_long com; 1991541Srgrimes caddr_t data; 2001541Srgrimes int flag; 2011541Srgrimes struct proc *p; 2021541Srgrimes{ 2031541Srgrimes long l; 2041541Srgrimes int s; 2051541Srgrimes 2061541Srgrimes switch (com) { 2071541Srgrimes 2081541Srgrimes /* return number of characters immediately available */ 2091541Srgrimes case FIONREAD: 2101541Srgrimes s = splhigh(); 2111541Srgrimes l = msgbufp->msg_bufx - msgbufp->msg_bufr; 2121541Srgrimes splx(s); 2131541Srgrimes if (l < 0) 21436179Sphk l += msgbufp->msg_size; 2151541Srgrimes *(int *)data = l; 2161541Srgrimes break; 2171541Srgrimes 2181541Srgrimes case FIONBIO: 2191541Srgrimes break; 2201541Srgrimes 2211541Srgrimes case FIOASYNC: 2221541Srgrimes if (*(int *)data) 2231541Srgrimes logsoftc.sc_state |= LOG_ASYNC; 2241541Srgrimes else 2251541Srgrimes logsoftc.sc_state &= ~LOG_ASYNC; 2261541Srgrimes break; 2271541Srgrimes 22841086Struckman case FIOSETOWN: 22941086Struckman return (fsetown(*(int *)data, &logsoftc.sc_sigio)); 23041086Struckman 23141086Struckman case FIOGETOWN: 23241086Struckman *(int *)data = fgetown(logsoftc.sc_sigio); 2331541Srgrimes break; 2341541Srgrimes 23541086Struckman /* This is deprecated, FIOSETOWN should be used instead. */ 23641086Struckman case TIOCSPGRP: 23741086Struckman return (fsetown(-(*(int *)data), &logsoftc.sc_sigio)); 23841086Struckman 23941086Struckman /* This is deprecated, FIOGETOWN should be used instead */ 2401541Srgrimes case TIOCGPGRP: 24141086Struckman *(int *)data = -fgetown(logsoftc.sc_sigio); 2421541Srgrimes break; 2431541Srgrimes 2441541Srgrimes default: 2458161Sjkh return (ENOTTY); 2461541Srgrimes } 2471541Srgrimes return (0); 2481541Srgrimes} 24912517Sjulian 25033679Sbdestatic int log_devsw_installed; 25117040Swollman#ifdef DEVFS 25212675Sjulianstatic void *log_devfs_token; 25317040Swollman#endif 25412517Sjulian 25529506Sbdestatic void log_drvinit __P((void *unused)); 25612675Sjulianstatic void 25729506Sbdelog_drvinit(unused) 25829506Sbde void *unused; 25912517Sjulian{ 26012517Sjulian dev_t dev; 26112517Sjulian 26212517Sjulian if( ! log_devsw_installed ) { 26312517Sjulian dev = makedev(CDEV_MAJOR,0); 26412517Sjulian cdevsw_add(&dev,&log_cdevsw,NULL); 26512517Sjulian log_devsw_installed = 1; 26612517Sjulian#ifdef DEVFS 26714851Sbde log_devfs_token = devfs_add_devswf(&log_cdevsw, 0, DV_CHR, 26814851Sbde UID_ROOT, GID_WHEEL, 0600, 26914851Sbde "klog"); 27012521Sjulian#endif 27112517Sjulian } 27212517Sjulian} 27312517Sjulian 27412517SjulianSYSINIT(logdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,log_drvinit,NULL) 275