/* $NetBSD: syslog.c,v 1.30 2003/08/07 16:42:57 agc Exp $ */ /* * Copyright (c) 1983, 1988, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #if defined(LIBC_SCCS) && !defined(lint) #if 0 static char sccsid[] = "@(#)syslog.c 8.5 (Berkeley) 4/29/95"; #else __RCSID("$NetBSD: syslog.c,v 1.30 2003/08/07 16:42:57 agc Exp $"); #endif #endif /* LIBC_SCCS and not lint */ #include "namespace.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "reentrant.h" #ifdef __weak_alias __weak_alias(closelog,_closelog) __weak_alias(openlog,_openlog) __weak_alias(setlogmask,_setlogmask) __weak_alias(syslog,_syslog) __weak_alias(vsyslog,_vsyslog) #endif static int LogFile = -1; /* fd for log */ static int connected; /* have done connect */ static int LogStat = 0; /* status bits, set by openlog() */ static const char *LogTag = NULL; /* string to tag the entry with */ static int LogFacility = LOG_USER; /* default facility code */ static int LogMask = 0xff; /* mask of priorities to be logged */ static void openlog_unlocked __P((const char *, int, int)); static void closelog_unlocked __P((void)); #ifdef _REENTRANT static mutex_t syslog_mutex = MUTEX_INITIALIZER; #endif #ifdef lint static const int ZERO = 0; #else #define ZERO 0 #endif /* * syslog, vsyslog -- * print message on log file; output is intended for syslogd(8). */ void syslog(int pri, const char *fmt, ...) { va_list ap; va_start(ap, fmt); vsyslog(pri, fmt, ap); va_end(ap); } void vsyslog(pri, fmt, ap) int pri; const char *fmt; _BSD_VA_LIST_ ap; { size_t cnt; char ch, *p, *t; time_t now; struct tm tmnow; int fd, saved_errno, tries; #define TBUF_LEN 2048 #define FMT_LEN 1024 char *stdp = NULL; /* pacify gcc */ char tbuf[TBUF_LEN], fmt_cpy[FMT_LEN]; size_t tbuf_left, fmt_left, prlen; #define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID /* Check for invalid bits. */ if (pri & ~(LOG_PRIMASK|LOG_FACMASK)) { syslog(INTERNALLOG, "syslog: unknown facility/priority: %x", pri); pri &= LOG_PRIMASK|LOG_FACMASK; } /* Check priority against setlogmask values. */ if (!(LOG_MASK(LOG_PRI(pri)) & LogMask)) return; saved_errno = errno; /* Set default facility if none specified. */ if ((pri & LOG_FACMASK) == 0) pri |= LogFacility; /* Build the message. */ /* * Although it's tempting, we can't ignore the possibility of * overflowing the buffer when assembling the "fixed" portion * of the message. Strftime's "%h" directive expands to the * locale's abbreviated month name, but if the user has the * ability to construct to his own locale files, it may be * arbitrarily long. */ (void)time(&now); p = tbuf; tbuf_left = TBUF_LEN; #define DEC() \ do { \ if (prlen >= tbuf_left) \ prlen = tbuf_left - 1; \ p += prlen; \ tbuf_left -= prlen; \ } while (ZERO) prlen = snprintf(p, tbuf_left, "<%d>", pri); DEC(); tzset(); /* strftime() implies tzset(), localtime_r() doesn't. */ prlen = strftime(p, tbuf_left, "%h %e %T ", localtime_r(&now, &tmnow)); DEC(); if (LogStat & LOG_PERROR) stdp = p; if (LogTag == NULL) LogTag = getprogname(); if (LogTag != NULL) { prlen = snprintf(p, tbuf_left, "%s", LogTag); DEC(); } if (LogStat & LOG_PID) { prlen = snprintf(p, tbuf_left, "[%d]", getpid()); DEC(); } if (LogTag != NULL) { if (tbuf_left > 1) { *p++ = ':'; tbuf_left--; } if (tbuf_left > 1) { *p++ = ' '; tbuf_left--; } } /* * We wouldn't need this mess if printf handled %m, or if * strerror() had been invented before syslog(). */ for (t = fmt_cpy, fmt_left = FMT_LEN; (ch = *fmt) != '\0'; ++fmt) { if (ch == '%' && fmt[1] == 'm') { ++fmt; prlen = snprintf(t, fmt_left, "%s", strerror(saved_errno)); if (prlen >= fmt_left) prlen = fmt_left - 1; t += prlen; fmt_left -= prlen; } else { if (fmt_left > 1) { *t++ = ch; fmt_left--; } } } *t = '\0'; prlen = vsnprintf(p, tbuf_left, fmt_cpy, ap); DEC(); cnt = p - tbuf; /* Output to stderr if requested. */ if (LogStat & LOG_PERROR) { struct iovec iov[2]; iov[0].iov_base = stdp; iov[0].iov_len = cnt - (stdp - tbuf); iov[1].iov_base = "\n"; iov[1].iov_len = 1; (void)writev(STDERR_FILENO, iov, 2); } /* Get connected, output the message to the local logger. */ mutex_lock(&syslog_mutex); /* * Try to send it twice. If the first try fails, we might * be able to simply reconnect and send the message (which * means syslogd was restarted since we connected the first * time). If the second attempt doesn't work, then something * else is wrong and there's probably not much we can do * here. */ for (tries = 1; tries <= 2; tries++) { if (!connected) openlog_unlocked(LogTag, LogStat | LOG_NDELAY, 0); if (send(LogFile, tbuf, cnt, 0) >= 0) { mutex_unlock(&syslog_mutex); return; } else closelog_unlocked(); } mutex_unlock(&syslog_mutex); /* * Output the message to the console; don't worry about blocking, * if console blocks everything will. Make sure the error reported * is the one from the syslogd failure. */ if (LogStat & LOG_CONS && (fd = open(_PATH_CONSOLE, O_WRONLY, 0)) >= 0) { struct iovec iov[2]; p = strchr(tbuf, '>') + 1; iov[0].iov_base = p; iov[0].iov_len = cnt - (p - tbuf); iov[1].iov_base = "\r\n"; iov[1].iov_len = 2; (void)writev(fd, iov, 2); (void)close(fd); } } static struct sockaddr_un SyslogAddr; /* AF_LOCAL address of local logger */ static void openlog_unlocked(ident, logstat, logfac) const char *ident; int logstat, logfac; { if (ident != NULL) LogTag = ident; LogStat = logstat; if (logfac != 0 && (logfac &~ LOG_FACMASK) == 0) LogFacility = logfac; if (LogFile == -1) { SyslogAddr.sun_family = AF_LOCAL; (void)strncpy(SyslogAddr.sun_path, _PATH_LOG, sizeof(SyslogAddr.sun_path)); if (LogStat & LOG_NDELAY) { if ((LogFile = socket(AF_LOCAL, SOCK_DGRAM, 0)) == -1) return; (void)fcntl(LogFile, F_SETFD, 1); } } if (LogFile != -1 && !connected) { if (connect(LogFile, (struct sockaddr *)(void *)&SyslogAddr, SUN_LEN(&SyslogAddr)) == -1) { (void)close(LogFile); LogFile = -1; } else connected = 1; } } void openlog(ident, logstat, logfac) const char *ident; int logstat, logfac; { mutex_lock(&syslog_mutex); openlog_unlocked(ident, logstat, logfac); mutex_unlock(&syslog_mutex); } static void closelog_unlocked() { (void)close(LogFile); LogFile = -1; connected = 0; } void closelog() { mutex_lock(&syslog_mutex); closelog_unlocked(); mutex_unlock(&syslog_mutex); } /* setlogmask -- set the log mask level */ int setlogmask(pmask) int pmask; { int omask; omask = LogMask; if (pmask != 0) LogMask = pmask; return (omask); }