#if !defined(lint) && defined(SCCSIDS) static char sccsid[] = "@(#)syslog.c 1.1 92/07/30 SMI"; /* from UCB 5.9 5/7/86 */ #endif /* * Copyright (c) 1983 Regents of the University of California. * All rights reserved. The Berkeley software License Agreement * specifies the terms and conditions for redistribution. */ /* * SYSLOG -- print message on log file * * This routine looks a lot like printf, except that it * outputs to the log file instead of the standard output. * Also: * adds a timestamp, * prints the module name in front of the message, * has some other formatting types (or will sometime), * adds a newline on the end of the message. * * The output of this routine is intended to be read by /etc/syslogd. * * Author: Eric Allman * Modified to use UNIX domain IPC by Ralph Campbell */ #include #include #include #include #include #include #include #include #include #include #define MAXLINE 1024 /* max message size */ #define NULL 0 /* manifest */ #define PRIMASK(p) (1 #define PRIFAC(p) (((p) & LOG_FACMASK) >> 3) #define IMPORTANT LOG_ERR static char *logname = "/dev/log"; static char *ctty = "/dev/console"; static struct _syslog { int _LogFile; int _LogStat; char *_LogTag; int _LogMask; struct sockaddr _SyslogAddr; char *_SyslogHost; int _LogFacility; } *_syslog; #define LogFile (_syslog->_LogFile) #define LogStat (_syslog->_LogStat) #define LogTag (_syslog->_LogTag) #define LogMask (_syslog->_LogMask) #define SyslogAddr (_syslog->_SyslogAddr) #define SyslogHost (_syslog->_SyslogHost) #define LogFacility (_syslog->_LogFacility) extern int errno, sys_nerr; extern char *sys_errlist[]; extern char *calloc(); extern time_t time(); extern unsigned int alarm(); static int allocstatic() { _syslog = (struct _syslog *)calloc(1, sizeof (struct _syslog)); if (_syslog == 0) return (0); /* can't do it */ LogFile = -1; /* fd for log */ LogStat = 0; /* status bits, set by openlog() */ LogTag = "syslog"; /* string to tag the entry with */ LogMask = 0xff; /* mask of priorities to be logged */ LogFacility = LOG_USER; /* default facility code */ return (1); } /*VARARGS2*/ syslog(pri, fmt, va_alist) int pri; char *fmt; va_dcl { va_list ap; va_start(ap); vsyslog(pri, fmt, ap); va_end(ap); } vsyslog(pri, fmt, ap) int pri; char *fmt; va_list ap; { char buf[MAXLINE + 1], outline[MAXLINE + 1]; register char *b, *f, *o; register int c; long now; int pid, olderrno = errno; if (_syslog == 0 && !allocstatic()) return; /* see if we should just throw out this message */ if (pri = LOG_NFACILITIES || (PRIMASK(pri) & LogMask) == 0) return; if (LogFile < 0) openlog(LogTag, LogStat | LOG_NDELAY, 0); /* set default facility if none specified */ if ((pri & LOG_FACMASK) == 0) pri |= LogFacility; /* build the message */ o = outline; (void)sprintf(o, "", pri); o += strlen(o); (void)time(&now); (void)sprintf(o, "%.15s ", ctime(&now) + 4); o += strlen(o); if (LogTag) { (void)strcpy(o, LogTag); o += strlen(o); } if (LogStat & LOG_PID) { (void)sprintf(o, "[%d]", getpid()); o += strlen(o); } if (LogTag) { (void)strcpy(o, ": "); o += 2; } b = buf; f = fmt; while ((c = *f++) != '\0' && c != '\n' && b < &buf[MAXLINE]) { if (c != '%') { *b++ = c; continue; } if ((c = *f++) != 'm') { *b++ = '%'; *b++ = c; continue; } if ((unsigned)olderrno > sys_nerr) (void)sprintf(b, "error %d", olderrno); else (void)strcpy(b, sys_errlist[olderrno]); b += strlen(b); } *b++ = '\n'; *b = '\0'; (void)vsprintf(o, buf, ap); c = strlen(outline); if (c > MAXLINE) c = MAXLINE; /* output the message to the local logger */ if (sendto(LogFile, outline, c, 0, &SyslogAddr, sizeof SyslogAddr) >= 0) return; if (!(LogStat & LOG_CONS)) return; /* output the message to the console */ pid = vfork(); if (pid == -1) return; if (pid == 0) { int fd; (void)signal(SIGALRM, SIG_DFL); (void)sigsetmask(sigblock(0) & ~sigmask(SIGALRM)); (void)alarm(5); fd = open(ctty, O_WRONLY); (void)alarm(0); (void)strcat(o, "\r"); o = index(outline, '>') + 1; (void)write(fd, o, c + 1 - (o - outline)); (void)close(fd); _exit(0); } if (!(LogStat & LOG_NOWAIT)) while ((c = wait((int *)0)) > 0 && c != pid) ; } /* * OPENLOG -- open system log */ openlog(ident, logstat, logfac) char *ident; int logstat, logfac; { if (_syslog == 0 && !allocstatic()) return; if (ident != NULL) LogTag = ident; LogStat = logstat; if (logfac != 0) LogFacility = logfac & LOG_FACMASK; if (LogFile >= 0) return; SyslogAddr.sa_family = AF_UNIX; (void)strncpy(SyslogAddr.sa_data, logname, sizeof SyslogAddr.sa_data); if (LogStat & LOG_NDELAY) { LogFile = socket(AF_UNIX, SOCK_DGRAM, 0); (void)fcntl(LogFile, F_SETFD, 1); } } /* * CLOSELOG -- close the system log */ closelog() { if (_syslog == 0) return; (void) close(LogFile); LogFile = -1; } /* * SETLOGMASK -- set the log mask level */ setlogmask(pmask) int pmask; { int omask; if (_syslog == 0 && !allocstatic()) return (-1); omask = LogMask; if (pmask != 0) LogMask = pmask; return (omask); }
