2 * Copyright (c) 1983, 1988, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid
[] = "@(#)syslog.c 8.4 (Berkeley) 3/18/94";
32 #endif /* LIBC_SCCS and not lint */
34 #include <libio/libioP.h>
39 #include <stdio_ext.h>
40 #include <sys/socket.h>
45 static int LogType
= SOCK_DGRAM
; /* type of socket connection */
46 static int LogFile
= -1; /* fd for log */
47 static bool connected
; /* have done connect */
48 static int LogStat
; /* status bits, set by openlog() */
49 static const char *LogTag
; /* string to tag the entry with */
50 static int LogFacility
= LOG_USER
; /* default facility code */
51 static int LogMask
= 0xff; /* mask of priorities to be logged */
52 extern char *__progname
; /* Program name, from crt0. */
54 /* Define the lock. */
55 __libc_lock_define_initialized (static, syslog_lock
)
56 static void openlog_internal (const char *, int, int);
57 static void closelog_internal (void);
62 struct sigaction
*oldaction
;
66 cancel_handler (void *ptr
)
68 /* Restore the old signal handler. */
69 struct cleanup_arg
*clarg
= (struct cleanup_arg
*) ptr
;
72 /* Free the memstream buffer, */
76 __libc_lock_unlock (syslog_lock
);
82 * print message on log file; output is intended for syslogd(8).
85 __syslog (int pri
, const char *fmt
, ...)
90 __vsyslog_internal (pri
, fmt
, ap
, 0);
93 ldbl_hidden_def (__syslog
, syslog
)
94 ldbl_strong_alias (__syslog
, syslog
)
97 __vsyslog (int pri
, const char *fmt
, va_list ap
)
99 __vsyslog_internal (pri
, fmt
, ap
, 0);
101 ldbl_weak_alias (__vsyslog
, vsyslog
)
104 ___syslog_chk (int pri
, int flag
, const char *fmt
, ...)
109 __vsyslog_internal (pri
, fmt
, ap
, (flag
> 0) ? PRINTF_FORTIFY
: 0);
112 ldbl_hidden_def (___syslog_chk
, __syslog_chk
)
113 ldbl_strong_alias (___syslog_chk
, __syslog_chk
)
116 __vsyslog_chk (int pri
, int flag
, const char *fmt
, va_list ap
)
118 __vsyslog_internal (pri
, fmt
, ap
, (flag
> 0) ? PRINTF_FORTIFY
: 0);
122 __vsyslog_internal (int pri
, const char *fmt
, va_list ap
,
123 unsigned int mode_flags
)
125 /* Try to use a static buffer as an optimization. */
130 int saved_errno
= errno
;
132 #define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID
133 /* Check for invalid bits. */
134 if (pri
& ~(LOG_PRIMASK
| LOG_FACMASK
))
136 syslog (INTERNALLOG
, "syslog: unknown facility/priority: %x", pri
);
137 pri
&= LOG_PRIMASK
| LOG_FACMASK
;
140 /* Prepare for multiple users. We have to take care: most syscalls we are
141 using are cancellation points. */
142 struct cleanup_arg clarg
= { NULL
, NULL
};
143 __libc_cleanup_push (cancel_handler
, &clarg
);
144 __libc_lock_lock (syslog_lock
);
146 /* Check priority against setlogmask values. */
147 if ((LOG_MASK (LOG_PRI (pri
)) & LogMask
) == 0)
150 /* Set default facility if none specified. */
151 if ((pri
& LOG_FACMASK
) == 0)
154 pid_t pid
= LogStat
& LOG_PID
? __getpid () : 0;
156 /* "%b %e %H:%M:%S " */
157 char timestamp
[sizeof "MMM DD hh:mm:ss "];
158 __time64_t now
= time64_now ();
160 struct tm
*now_tmp
= __localtime64_r (&now
, &now_tm
);
161 bool has_ts
= now_tmp
!= NULL
;
163 /* In the unlikely case of localtime_r failure (tm_year out of int range)
164 skip the hostname so the message is handled as valid PRI but without
165 TIMESTAMP or invalid TIMESTAMP (which should force the relay to add the
166 timestamp itself). */
168 __strftime_l (timestamp
, sizeof timestamp
, "%h %e %T ", now_tmp
,
171 #define SYSLOG_HEADER(__pri, __timestamp, __msgoff, pid) \
172 "<%d>%s%n%s%s%.0d%s: ", \
173 __pri, __timestamp, __msgoff, \
174 LogTag == NULL ? __progname : LogTag, \
175 "[" + (pid == 0), pid, "]" + (pid == 0)
177 #define SYSLOG_HEADER_WITHOUT_TS(__pri, __msgoff) \
178 "<%d>: %n", __pri, __msgoff
182 l
= __snprintf (bufs
, sizeof bufs
,
183 SYSLOG_HEADER (pri
, timestamp
, &msgoff
, pid
));
185 l
= __snprintf (bufs
, sizeof bufs
,
186 SYSLOG_HEADER_WITHOUT_TS (pri
, &msgoff
));
187 if (0 <= l
&& l
< sizeof bufs
)
192 /* Restore errno for %m format. */
193 __set_errno (saved_errno
);
195 int vl
= __vsnprintf_internal (bufs
+ l
, sizeof bufs
- l
, fmt
, apc
,
197 if (0 <= vl
&& vl
< sizeof bufs
- l
)
206 buf
= malloc ((bufsize
+ 1) * sizeof (char));
209 /* Tell the cancellation handler to free this buffer. */
213 __snprintf (buf
, l
+ 1,
214 SYSLOG_HEADER (pri
, timestamp
, &msgoff
, pid
));
216 __snprintf (buf
, l
+ 1,
217 SYSLOG_HEADER_WITHOUT_TS (pri
, &msgoff
));
221 __vsnprintf_internal (buf
+ l
, bufsize
- l
+ 1, fmt
, apc
,
227 /* Nothing much to do but emit an error message. */
228 bufsize
= __snprintf (bufs
, sizeof bufs
,
229 "out of memory[%d]", __getpid ());
234 /* Output to stderr if requested. */
235 if (LogStat
& LOG_PERROR
)
236 __dprintf (STDERR_FILENO
, "%s%s", buf
+ msgoff
,
237 "\n" + (buf
[bufsize
- 1] == '\n'));
239 /* Get connected, output the message to the local logger. */
241 openlog_internal (NULL
, LogStat
| LOG_NDELAY
, LogFacility
);
243 /* If we have a SOCK_STREAM connection, also send ASCII NUL as a record
245 if (LogType
== SOCK_STREAM
)
248 if (!connected
|| __send (LogFile
, buf
, bufsize
, MSG_NOSIGNAL
) < 0)
252 /* Try to reopen the syslog connection. Maybe it went down. */
253 closelog_internal ();
254 openlog_internal (NULL
, LogStat
| LOG_NDELAY
, LogFacility
);
257 if (!connected
|| __send (LogFile
, buf
, bufsize
, MSG_NOSIGNAL
) < 0)
259 closelog_internal (); /* attempt re-open next time */
261 * Output the message to the console; don't worry
262 * about blocking, if console blocks everything will.
263 * Make sure the error reported is the one from the
267 if (LogStat
& LOG_CONS
&&
268 (fd
= __open (_PATH_CONSOLE
, O_WRONLY
| O_NOCTTY
269 | O_CLOEXEC
, 0)) >= 0)
271 __dprintf (fd
, "%s\r\n", buf
+ msgoff
);
278 /* End of critical section. */
279 __libc_cleanup_pop (0);
280 __libc_lock_unlock (syslog_lock
);
286 /* AF_UNIX address of local logger */
287 static const struct sockaddr_un SyslogAddr
=
289 .sun_family
= AF_UNIX
,
290 .sun_path
= _PATH_LOG
294 openlog_internal (const char *ident
, int logstat
, int logfac
)
299 if ((logfac
& ~LOG_FACMASK
) == 0)
300 LogFacility
= logfac
;
307 if (LogStat
& LOG_NDELAY
)
309 LogFile
= __socket (AF_UNIX
, LogType
| SOCK_CLOEXEC
, 0);
314 if (LogFile
!= -1 && !connected
)
316 int old_errno
= errno
;
317 if (__connect (LogFile
, &SyslogAddr
, sizeof (SyslogAddr
)) == -1)
319 int saved_errno
= errno
;
323 __set_errno (old_errno
);
324 if (saved_errno
== EPROTOTYPE
)
326 /* retry with the other type: */
327 LogType
= LogType
== SOCK_DGRAM
? SOCK_STREAM
: SOCK_DGRAM
;
340 openlog (const char *ident
, int logstat
, int logfac
)
342 /* Protect against multiple users and cancellation. */
343 __libc_cleanup_push (cancel_handler
, NULL
);
344 __libc_lock_lock (syslog_lock
);
346 openlog_internal (ident
, logstat
, logfac
);
348 __libc_cleanup_pop (1);
352 closelog_internal (void)
365 /* Protect against multiple users and cancellation. */
366 __libc_cleanup_push (cancel_handler
, NULL
);
367 __libc_lock_lock (syslog_lock
);
369 closelog_internal ();
371 LogType
= SOCK_DGRAM
; /* this is the default */
374 __libc_cleanup_pop (1);
377 /* setlogmask -- set the log mask level */
379 setlogmask (int pmask
)
383 /* Protect against multiple users. */
384 __libc_lock_lock (syslog_lock
);
390 __libc_lock_unlock (syslog_lock
);