subr_log.c revision 12521
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 3412521Sjulian * $Id: subr_log.c,v 1.11 1995/11/29 10:48:25 julian Exp $ 351541Srgrimes */ 361541Srgrimes 371541Srgrimes/* 381541Srgrimes * Error log buffer for kernel printf's. 391541Srgrimes */ 401541Srgrimes 411541Srgrimes#include <sys/param.h> 421541Srgrimes#include <sys/systm.h> 431541Srgrimes#include <sys/proc.h> 441541Srgrimes#include <sys/vnode.h> 451541Srgrimes#include <sys/ioctl.h> 461541Srgrimes#include <sys/msgbuf.h> 471541Srgrimes#include <sys/file.h> 483308Sphk#include <sys/signalvar.h> 491541Srgrimes 5012517Sjulian#ifdef JREMOD 5112517Sjulian#include <sys/conf.h> 5212517Sjulian#include <sys/kernel.h> 5312517Sjulian#ifdef DEVFS 5412517Sjulian#include <sys/devfsext.h> 5512517Sjulian#endif /*DEVFS*/ 5612517Sjulian#define CDEV_MAJOR 7 5712517Sjulian#endif /*JREMOD*/ 5812517Sjulian 591541Srgrimes#define LOG_RDPRI (PZERO + 1) 601541Srgrimes 611541Srgrimes#define LOG_ASYNC 0x04 621541Srgrimes#define LOG_RDWAIT 0x08 631541Srgrimes 641541Srgrimesstruct logsoftc { 651541Srgrimes int sc_state; /* see above for possibilities */ 661541Srgrimes struct selinfo sc_selp; /* process waiting on select call */ 671541Srgrimes int sc_pgid; /* process/group for async I/O */ 681541Srgrimes} logsoftc; 691541Srgrimes 701541Srgrimesint log_open; /* also used in log() */ 711541Srgrimes 721541Srgrimes/*ARGSUSED*/ 731549Srgrimesint 741541Srgrimeslogopen(dev, flags, mode, p) 751541Srgrimes dev_t dev; 761541Srgrimes int flags, mode; 771541Srgrimes struct proc *p; 781541Srgrimes{ 791541Srgrimes if (log_open) 801541Srgrimes return (EBUSY); 811541Srgrimes log_open = 1; 821541Srgrimes logsoftc.sc_pgid = p->p_pid; /* signal process only */ 831541Srgrimes return (0); 841541Srgrimes} 851541Srgrimes 861541Srgrimes/*ARGSUSED*/ 871549Srgrimesint 881541Srgrimeslogclose(dev, flag, mode, p) 891541Srgrimes dev_t dev; 901541Srgrimes int flag, mode; 911541Srgrimes struct proc *p; 921541Srgrimes{ 931541Srgrimes 941541Srgrimes log_open = 0; 951541Srgrimes logsoftc.sc_state = 0; 961541Srgrimes return (0); 971541Srgrimes} 981541Srgrimes 991541Srgrimes/*ARGSUSED*/ 1001549Srgrimesint 1011541Srgrimeslogread(dev, uio, flag) 1021541Srgrimes dev_t dev; 1031541Srgrimes struct uio *uio; 1041541Srgrimes int flag; 1051541Srgrimes{ 1061541Srgrimes register struct msgbuf *mbp = msgbufp; 1071541Srgrimes register long l; 1081541Srgrimes register int s; 1091541Srgrimes int error = 0; 1101541Srgrimes 1111541Srgrimes s = splhigh(); 1121541Srgrimes while (mbp->msg_bufr == mbp->msg_bufx) { 1131541Srgrimes if (flag & IO_NDELAY) { 1141541Srgrimes splx(s); 1151541Srgrimes return (EWOULDBLOCK); 1161541Srgrimes } 1171541Srgrimes logsoftc.sc_state |= LOG_RDWAIT; 1183098Sphk if ((error = tsleep((caddr_t)mbp, LOG_RDPRI | PCATCH, 1193098Sphk "klog", 0))) { 1201541Srgrimes splx(s); 1211541Srgrimes return (error); 1221541Srgrimes } 1231541Srgrimes } 1241541Srgrimes splx(s); 1251541Srgrimes logsoftc.sc_state &= ~LOG_RDWAIT; 1261541Srgrimes 1271541Srgrimes while (uio->uio_resid > 0) { 1281541Srgrimes l = mbp->msg_bufx - mbp->msg_bufr; 1291541Srgrimes if (l < 0) 1301541Srgrimes l = MSG_BSIZE - mbp->msg_bufr; 1311541Srgrimes l = min(l, uio->uio_resid); 1321541Srgrimes if (l == 0) 1331541Srgrimes break; 1341541Srgrimes error = uiomove((caddr_t)&mbp->msg_bufc[mbp->msg_bufr], 1351541Srgrimes (int)l, uio); 1361541Srgrimes if (error) 1371541Srgrimes break; 1381541Srgrimes mbp->msg_bufr += l; 1399979Sdg if (mbp->msg_bufr >= MSG_BSIZE) 1401541Srgrimes mbp->msg_bufr = 0; 1411541Srgrimes } 1421541Srgrimes return (error); 1431541Srgrimes} 1441541Srgrimes 1451541Srgrimes/*ARGSUSED*/ 1461549Srgrimesint 1471541Srgrimeslogselect(dev, rw, p) 1481541Srgrimes dev_t dev; 1491541Srgrimes int rw; 1501541Srgrimes struct proc *p; 1511541Srgrimes{ 1521541Srgrimes int s = splhigh(); 1531541Srgrimes 1541541Srgrimes switch (rw) { 1551541Srgrimes 1561541Srgrimes case FREAD: 1571541Srgrimes if (msgbufp->msg_bufr != msgbufp->msg_bufx) { 1581541Srgrimes splx(s); 1591541Srgrimes return (1); 1601541Srgrimes } 1611541Srgrimes selrecord(p, &logsoftc.sc_selp); 1621541Srgrimes break; 1631541Srgrimes } 1641541Srgrimes splx(s); 1651541Srgrimes return (0); 1661541Srgrimes} 1671541Srgrimes 1681549Srgrimesvoid 1691541Srgrimeslogwakeup() 1701541Srgrimes{ 1711541Srgrimes struct proc *p; 1721541Srgrimes 1731541Srgrimes if (!log_open) 1741541Srgrimes return; 1751541Srgrimes selwakeup(&logsoftc.sc_selp); 1761541Srgrimes if (logsoftc.sc_state & LOG_ASYNC) { 1771541Srgrimes if (logsoftc.sc_pgid < 0) 1788876Srgrimes gsignal(-logsoftc.sc_pgid, SIGIO); 1793098Sphk else if ((p = pfind(logsoftc.sc_pgid))) 1801541Srgrimes psignal(p, SIGIO); 1811541Srgrimes } 1821541Srgrimes if (logsoftc.sc_state & LOG_RDWAIT) { 1831541Srgrimes wakeup((caddr_t)msgbufp); 1841541Srgrimes logsoftc.sc_state &= ~LOG_RDWAIT; 1851541Srgrimes } 1861541Srgrimes} 1871541Srgrimes 1881541Srgrimes/*ARGSUSED*/ 1891549Srgrimesint 1901541Srgrimeslogioctl(dev, com, data, flag, p) 1911541Srgrimes dev_t dev; 1921541Srgrimes int com; 1931541Srgrimes caddr_t data; 1941541Srgrimes int flag; 1951541Srgrimes struct proc *p; 1961541Srgrimes{ 1971541Srgrimes long l; 1981541Srgrimes int s; 1991541Srgrimes 2001541Srgrimes switch (com) { 2011541Srgrimes 2021541Srgrimes /* return number of characters immediately available */ 2031541Srgrimes case FIONREAD: 2041541Srgrimes s = splhigh(); 2051541Srgrimes l = msgbufp->msg_bufx - msgbufp->msg_bufr; 2061541Srgrimes splx(s); 2071541Srgrimes if (l < 0) 2081541Srgrimes l += MSG_BSIZE; 2091541Srgrimes *(int *)data = l; 2101541Srgrimes break; 2111541Srgrimes 2121541Srgrimes case FIONBIO: 2131541Srgrimes break; 2141541Srgrimes 2151541Srgrimes case FIOASYNC: 2161541Srgrimes if (*(int *)data) 2171541Srgrimes logsoftc.sc_state |= LOG_ASYNC; 2181541Srgrimes else 2191541Srgrimes logsoftc.sc_state &= ~LOG_ASYNC; 2201541Srgrimes break; 2211541Srgrimes 2221541Srgrimes case TIOCSPGRP: 2231541Srgrimes logsoftc.sc_pgid = *(int *)data; 2241541Srgrimes break; 2251541Srgrimes 2261541Srgrimes case TIOCGPGRP: 2271541Srgrimes *(int *)data = logsoftc.sc_pgid; 2281541Srgrimes break; 2291541Srgrimes 2301541Srgrimes default: 2318161Sjkh return (ENOTTY); 2321541Srgrimes } 2331541Srgrimes return (0); 2341541Srgrimes} 23512517Sjulian 23612517Sjulian#ifdef JREMOD 23712517Sjulianstruct cdevsw log_cdevsw = 23812517Sjulian { logopen, logclose, logread, nowrite, /*7*/ 23912517Sjulian logioctl, nostop, nullreset, nodevtotty,/* klog */ 24012517Sjulian logselect, nommap, NULL }; 24112517Sjulian 24212517Sjulianstatic log_devsw_installed = 0; 24312517Sjulian 24412517Sjulianstatic void log_drvinit(void *unused) 24512517Sjulian{ 24612517Sjulian dev_t dev; 24712517Sjulian 24812517Sjulian if( ! log_devsw_installed ) { 24912517Sjulian dev = makedev(CDEV_MAJOR,0); 25012517Sjulian cdevsw_add(&dev,&log_cdevsw,NULL); 25112517Sjulian log_devsw_installed = 1; 25212517Sjulian#ifdef DEVFS 25312517Sjulian { 25412517Sjulian int x; 25512517Sjulian/* default for a simple device with no probe routine (usually delete this) */ 25612517Sjulian x=devfs_add_devsw( 25712517Sjulian/* path name devsw minor type uid gid perm*/ 25812517Sjulian "/", "log", major(dev), 0, DV_CHR, 0, 0, 0600); 25912517Sjulian } 26012521Sjulian#endif 26112517Sjulian } 26212517Sjulian} 26312517Sjulian 26412517SjulianSYSINIT(logdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,log_drvinit,NULL) 26512517Sjulian 26612517Sjulian#endif /* JREMOD */ 26712517Sjulian 268