1 /* 2 * Copyright (c) 1983, 1988 Regents of the University of California. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms are permitted 6 * provided that the above copyright notice and this paragraph are 7 * duplicated in all such forms and that any documentation, 8 * advertising materials, and other materials related to such 9 * distribution and use acknowledge that the software was developed 10 * by the University of California, Berkeley. The name of the 11 * University may not be used to endorse or promote products derived 12 * from this software without specific prior written permission. 13 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED 15 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. 16 */ 17 18 #if defined(LIBC_SCCS) && !defined(lint) 19 static char sccsid[] = "@(#)syslog.c 5.19 (Berkeley) 12/19/88"; 20 #endif /* LIBC_SCCS and not lint */ 21 22 /* 23 * SYSLOG -- print message on log file 24 * 25 * This routine looks a lot like printf, except that it outputs to the 26 * log file instead of the standard output. Also: 27 * adds a timestamp, 28 * prints the module name in front of the message, 29 * has some other formatting types (or will sometime), 30 * adds a newline on the end of the message. 31 * 32 * The output of this routine is intended to be read by syslogd(8). 33 * 34 * Author: Eric Allman 35 * Modified to use UNIX domain IPC by Ralph Campbell 36 */ 37 38 #include <sys/types.h> 39 #include <sys/socket.h> 40 #include <sys/file.h> 41 #include <sys/signal.h> 42 #include <sys/syslog.h> 43 #include <netdb.h> 44 #include <strings.h> 45 #include <varargs.h> 46 #include <stdio.h> 47 48 #define LOGNAME "/dev/log" 49 #define CONSOLE "/dev/console" 50 51 static int LogFile = -1; /* fd for log */ 52 static int connected; /* have done connect */ 53 static int LogStat = 0; /* status bits, set by openlog() */ 54 static char *LogTag = "syslog"; /* string to tag the entry with */ 55 static int LogFacility = LOG_USER; /* default facility code */ 56 57 syslog(pri, fmt, args) 58 int pri, args; 59 char *fmt; 60 { 61 vsyslog(pri, fmt, &args); 62 } 63 64 vsyslog(pri, fmt, ap) 65 int pri; 66 register char *fmt; 67 va_list ap; 68 { 69 extern int errno; 70 register int cnt; 71 register char *p; 72 time_t now, time(); 73 int pid, saved_errno; 74 char tbuf[2048], fmt_cpy[1024], *ctime(); 75 76 saved_errno = errno; 77 78 /* see if we should just throw out this message */ 79 if ((u_int)LOG_FAC(pri) >= LOG_NFACILITIES || 80 !LOG_MASK(LOG_PRI(pri)) || (pri &~ (LOG_PRIMASK|LOG_FACMASK))) 81 return; 82 if (LogFile < 0 || !connected) 83 openlog(LogTag, LogStat | LOG_NDELAY, 0); 84 85 /* set default facility if none specified */ 86 if ((pri & LOG_FACMASK) == 0) 87 pri |= LogFacility; 88 89 /* build the message */ 90 (void)time(&now); 91 (void)sprintf(tbuf, "<%d>%.15s ", pri, ctime(&now) + 4); 92 for (p = tbuf; *p; ++p); 93 if (LogTag) { 94 (void)strcpy(p, LogTag); 95 for (; *p; ++p); 96 } 97 if (LogStat & LOG_PID) { 98 (void)sprintf(p, "[%d]", getpid()); 99 for (; *p; ++p); 100 } 101 if (LogTag) { 102 *p++ = ':'; 103 *p++ = ' '; 104 } 105 106 /* substitute error message for %m */ 107 { 108 register char ch, *t1, *t2; 109 char *strerror(); 110 111 for (t1 = fmt_cpy; ch = *fmt; ++fmt) 112 if (ch == '%' && fmt[1] == 'm') { 113 ++fmt; 114 for (t2 = strerror(saved_errno); 115 *t1 = *t2++; ++t1); 116 } 117 else 118 *t1++ = ch; 119 } 120 121 (void)vsprintf(p, fmt_cpy, ap); 122 123 /* output the message to the local logger */ 124 if (send(LogFile, tbuf, cnt = strlen(tbuf), 0) >= 0 || 125 !(LogStat&LOG_CONS)) 126 return; 127 128 /* output the message to the console */ 129 pid = vfork(); 130 if (pid == -1) 131 return; 132 if (pid == 0) { 133 int fd; 134 long sigsetmask(); 135 136 (void)signal(SIGALRM, SIG_DFL); 137 sigsetmask((long)~sigmask(SIGALRM)); 138 (void)alarm((u_int)5); 139 if ((fd = open(CONSOLE, O_WRONLY, 0)) < 0) 140 return; 141 (void)alarm((u_int)0); 142 (void)strcat(tbuf, "\r"); 143 p = index(tbuf, '>') + 1; 144 (void)write(fd, p, cnt + 1 - (p - tbuf)); 145 (void)close(fd); 146 _exit(0); 147 } 148 if (!(LogStat & LOG_NOWAIT)) 149 while ((cnt = wait((int *)0)) > 0 && cnt != pid); 150 } 151 152 static struct sockaddr SyslogAddr; /* AF_UNIX address of local logger */ 153 /* 154 * OPENLOG -- open system log 155 */ 156 openlog(ident, logstat, logfac) 157 char *ident; 158 int logstat, logfac; 159 { 160 if (ident != NULL) 161 LogTag = ident; 162 LogStat = logstat; 163 if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0) 164 LogFacility = logfac; 165 if (LogFile == -1) { 166 SyslogAddr.sa_family = AF_UNIX; 167 strncpy(SyslogAddr.sa_data, LOGNAME, sizeof SyslogAddr.sa_data); 168 if (LogStat & LOG_NDELAY) { 169 LogFile = socket(AF_UNIX, SOCK_DGRAM, 0); 170 fcntl(LogFile, F_SETFD, 1); 171 } 172 } 173 if (LogFile != -1 && !connected && 174 connect(LogFile, &SyslogAddr, sizeof(SyslogAddr)) != -1) 175 connected = 1; 176 } 177 178 /* 179 * CLOSELOG -- close the system log 180 */ 181 closelog() 182 { 183 (void) close(LogFile); 184 LogFile = -1; 185 connected = 0; 186 } 187 188 static int LogMask = 0xff; /* mask of priorities to be logged */ 189 /* 190 * SETLOGMASK -- set the log mask level 191 */ 192 setlogmask(pmask) 193 int pmask; 194 { 195 int omask; 196 197 omask = LogMask; 198 if (pmask != 0) 199 LogMask = pmask; 200 return (omask); 201 } 202