/* * 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. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. 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. */ /* * 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 syslogd(8). * * Author: Eric Allman * Modified to use UNIX domain IPC by Ralph Campbell * Patched March 12, 1996 by A. Ian Vogelesang <vogelesang@hdshq.com> * - to correct the handling of message & format string truncation, * - to visibly tag truncated records to facilitate * investigation of such Bad Things with grep, and, * - to correct the handling of case where "write" * returns after writing only part of the message. * Rewritten by Martin Mares <mj@atrey.karlin.mff.cuni.cz> on May 14, 1997 * - better buffer overrun checks. * - special handling of "%m" removed as we use GNU sprintf which handles * it automatically. * - Major code cleanup. */ #include <sys/types.h> #include <sys/socket.h> #include <sys/file.h> #include <sys/signal.h> #include <sys/syslog.h> #include <sys/uio.h> #include <sys/wait.h> #include <netdb.h> #include <string.h> #include <time.h> #include <unistd.h> #include <errno.h> #include <stdarg.h> #include <paths.h> #include <stdio.h> #include <ctype.h> #include <signal.h> #include <bits/uClibc_mutex.h> __UCLIBC_MUTEX_STATIC(mylock, PTHREAD_MUTEX_INITIALIZER); /* !glibc_compat: glibc uses argv[0] by default * (default: if there was no openlog or if openlog passed NULL), * not string "syslog" */ static const char *LogTag = "syslog"; /* string to tag the entry with */ static int LogFile = -1; /* fd for log */ static smalluint connected; /* have done connect */ /* all bits in option argument for openlog fit in 8 bits */ static smalluint LogStat = 0; /* status bits, set by openlog */ /* default facility code if openlog is not called */ /* (this fits in 8 bits even without >> 3 shift, but playing extra safe) */ static smalluint LogFacility = LOG_USER >> 3; /* bits mask of priorities to be logged (eight prios - 8 bits is enough) */ static smalluint LogMask = 0xff; /* AF_UNIX address of local logger (we use struct sockaddr * instead of struct sockaddr_un since "/dev/log" is small enough) */ static const struct sockaddr SyslogAddr = { .sa_family = AF_UNIX, /* sa_family_t (usually a short) */ .sa_data = _PATH_LOG /* char [14] */ }; static void closelog_intern(int sig) { /* mylock must be held by the caller */ if (LogFile != -1) { (void) close(LogFile); } LogFile = -1; connected = 0; if (sig == 0) { /* called from closelog()? - reset to defaults */ LogStat = 0; LogTag = "syslog"; LogFacility = LOG_USER >> 3; LogMask = 0xff; } } static void openlog_intern(const char *ident, int logstat, int logfac) { int fd; int logType = SOCK_DGRAM; if (ident != NULL) LogTag = ident; LogStat = logstat; /* (we were checking also for logfac != 0, but it breaks * openlog(xx, LOG_KERN) since LOG_KERN == 0) */ if ((logfac & ~LOG_FACMASK) == 0) /* if we don't have invalid bits */ LogFacility = (unsigned)logfac >> 3; fd = LogFile; if (fd == -1) { retry: if (logstat & LOG_NDELAY) { LogFile = fd = socket(AF_UNIX, logType, 0); if (fd == -1) { return; } fcntl(fd, F_SETFD, FD_CLOEXEC); /* We don't want to block if e.g. syslogd is SIGSTOPed */ fcntl(fd, F_SETFL, O_NONBLOCK | fcntl(fd, F_GETFL)); } } if (fd != -1 && !connected) { if (connect(fd, &SyslogAddr, sizeof(SyslogAddr)) != -1) { connected = 1; } else { if (fd != -1) { close(fd); LogFile = fd = -1; } if (logType == SOCK_DGRAM) { logType = SOCK_STREAM; goto retry; } } } } /* * OPENLOG -- open system log */ void openlog(const char *ident, int logstat, int logfac) { __UCLIBC_MUTEX_LOCK(mylock); openlog_intern(ident, logstat, logfac); __UCLIBC_MUTEX_UNLOCK(mylock); } /* * syslog, vsyslog -- * print message on log file; output is intended for syslogd(8). */ static #ifndef __USE_BSD __always_inline #endif void __vsyslog(int pri, const char *fmt, va_list ap) { register char *p; char *last_chr, *head_end, *end, *stdp; time_t now; int fd, saved_errno; int rc; char tbuf[1024]; /* syslogd is unable to handle longer messages */ /* Just throw out this message if pri has bad bits. */ if ((pri & ~(LOG_PRIMASK|LOG_FACMASK)) != 0) return; saved_errno = errno; __UCLIBC_MUTEX_LOCK(mylock); /* See if we should just throw out this message according to LogMask. */ if ((LogMask & LOG_MASK(LOG_PRI(pri))) == 0) goto getout; if (LogFile < 0 || !connected) openlog_intern(NULL, LogStat | LOG_NDELAY, (int)LogFacility << 3); /* Set default facility if none specified. */ if ((pri & LOG_FACMASK) == 0) pri |= ((int)LogFacility << 3); /* Build the message. We know the starting part of the message can take * no longer than 64 characters plus length of the LogTag. So it's * safe to test only LogTag and use normal sprintf everywhere else. */ (void)time(&now); stdp = p = tbuf + sprintf(tbuf, "<%d>%.15s ", pri, ctime(&now) + 4); /*if (LogTag) - always true */ { if (strlen(LogTag) < sizeof(tbuf) - 64) p += sprintf(p, "%s", LogTag); else p += sprintf(p, "<BUFFER OVERRUN ATTEMPT>"); } if (LogStat & LOG_PID) p += sprintf(p, "[%d]", getpid()); /*if (LogTag) - always true */ { *p++ = ':'; *p++ = ' '; } head_end = p; /* We format the rest of the message. If the buffer becomes full, we mark * the message as truncated. Note that we require at least 2 free bytes * in the buffer as we might want to add "\r\n" there. */ end = tbuf + sizeof(tbuf) - 1; __set_errno(saved_errno); p += vsnprintf(p, end - p, fmt, ap); if (p >= end || p < head_end) { /* Returned -1 in case of error... */ static const char truncate_msg[12] = "[truncated] "; /* no NUL! */ memmove(head_end + sizeof(truncate_msg), head_end, end - head_end - sizeof(truncate_msg)); memcpy(head_end, truncate_msg, sizeof(truncate_msg)); if (p < head_end) { while (p < end && *p) { p++; } } else { p = end - 1; } } last_chr = p; /* Output to stderr if requested. */ if (LogStat & LOG_PERROR) { *last_chr = '\n'; (void)write(STDERR_FILENO, stdp, last_chr - stdp + 1); } /* Output the message to the local logger using NUL as a message delimiter. */ p = tbuf; *last_chr = '\0'; if (LogFile >= 0) { do { /* can't just use write, it can result in SIGPIPE */ rc = send(LogFile, p, last_chr + 1 - p, MSG_NOSIGNAL); if (rc < 0) { /* I don't think looping forever on EAGAIN is a good idea. * Imagine that syslogd is SIGSTOPed... */ if (/* (errno != EAGAIN) && */ (errno != EINTR)) { closelog_intern(1); /* 1: do not reset LogXXX globals to default */ goto write_err; } rc = 0; } p += rc; } while (p <= last_chr); goto getout; } write_err: /* * 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. */ /* should mode be O_WRONLY | O_NOCTTY? -- Uli */ /* yes, but in Linux "/dev/console" never becomes ctty anyway -- vda */ if ((LogStat & LOG_CONS) && (fd = open(_PATH_CONSOLE, O_WRONLY | O_NOCTTY)) >= 0) { p = strchr(tbuf, '>') + 1; last_chr[0] = '\r'; last_chr[1] = '\n'; (void)write(fd, p, last_chr - p + 2); (void)close(fd); } getout: __UCLIBC_MUTEX_UNLOCK(mylock); } #ifdef __USE_BSD strong_alias(__vsyslog,vsyslog) #endif void syslog(int pri, const char *fmt, ...) { va_list ap; va_start(ap, fmt); __vsyslog(pri, fmt, ap); va_end(ap); } libc_hidden_def(syslog) /* * CLOSELOG -- close the system log */ void closelog(void) { __UCLIBC_MUTEX_LOCK(mylock); closelog_intern(0); /* 0: reset LogXXX globals to default */ __UCLIBC_MUTEX_UNLOCK(mylock); } /* setlogmask -- set the log mask level */ int setlogmask(int pmask) { int omask; omask = LogMask; if (pmask != 0) { /* __UCLIBC_MUTEX_LOCK(mylock);*/ LogMask = pmask; /* __UCLIBC_MUTEX_UNLOCK(mylock);*/ } return omask; }