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>
46 static int LogType
= SOCK_DGRAM
; /* type of socket connection */
47 static int LogFile
= -1; /* fd for log */
48 static bool connected
; /* have done connect */
49 static int LogStat
; /* status bits, set by openlog() */
50 static const char *LogTag
; /* string to tag the entry with */
51 static int LogFacility
= LOG_USER
; /* default facility code */
52 static int LogMask
= 0xff; /* mask of priorities to be logged */
53 extern char *__progname
; /* Program name, from crt0. */
55 /* Define the lock. */
56 __libc_lock_define_initialized (static, syslog_lock
)
57 static void openlog_internal (const char *, int, int);
58 static void closelog_internal (void);
63 struct sigaction
*oldaction
;
67 cancel_handler (void *ptr
)
69 /* Restore the old signal handler. */
70 struct cleanup_arg
*clarg
= (struct cleanup_arg
*) ptr
;
73 /* Free the memstream buffer, */
77 __libc_lock_unlock (syslog_lock
);
83 * print message on log file; output is intended for syslogd(8).
86 __syslog (int pri
, const char *fmt
, ...)
91 __vsyslog_internal (pri
, fmt
, ap
, 0);
94 ldbl_hidden_def (__syslog
, syslog
)
95 ldbl_strong_alias (__syslog
, syslog
)
98 __vsyslog (int pri
, const char *fmt
, va_list ap
)
100 __vsyslog_internal (pri
, fmt
, ap
, 0);
102 ldbl_weak_alias (__vsyslog
, vsyslog
)
105 ___syslog_chk (int pri
, int flag
, const char *fmt
, ...)
110 __vsyslog_internal (pri
, fmt
, ap
, (flag
> 0) ? PRINTF_FORTIFY
: 0);
113 ldbl_hidden_def (___syslog_chk
, __syslog_chk
)
114 ldbl_strong_alias (___syslog_chk
, __syslog_chk
)
117 __vsyslog_chk (int pri
, int flag
, const char *fmt
, va_list ap
)
119 __vsyslog_internal (pri
, fmt
, ap
, (flag
> 0) ? PRINTF_FORTIFY
: 0);
123 __vsyslog_internal (int pri
, const char *fmt
, va_list ap
,
124 unsigned int mode_flags
)
126 /* Try to use a static buffer as an optimization. */
132 int saved_errno
= errno
;
134 #define INTERNALLOG LOG_ERR|LOG_CONS|LOG_PERROR|LOG_PID
135 /* Check for invalid bits. */
136 if (pri
& ~(LOG_PRIMASK
| LOG_FACMASK
))
138 syslog (INTERNALLOG
, "syslog: unknown facility/priority: %x", pri
);
139 pri
&= LOG_PRIMASK
| LOG_FACMASK
;
142 /* Prepare for multiple users. We have to take care: most syscalls we are
143 using are cancellation points. */
144 struct cleanup_arg clarg
= { NULL
, NULL
};
145 __libc_cleanup_push (cancel_handler
, &clarg
);
146 __libc_lock_lock (syslog_lock
);
148 /* Check priority against setlogmask values. */
149 if ((LOG_MASK (LOG_PRI (pri
)) & LogMask
) == 0)
152 /* Set default facility if none specified. */
153 if ((pri
& LOG_FACMASK
) == 0)
156 pid_t pid
= LogStat
& LOG_PID
? __getpid () : 0;
158 /* "%b %e %H:%M:%S " */
159 char timestamp
[sizeof "MMM DD hh:mm:ss "];
160 __time64_t now
= time64_now ();
162 struct tm
*now_tmp
= __localtime64_r (&now
, &now_tm
);
163 bool has_ts
= now_tmp
!= NULL
;
165 /* In the unlikely case of localtime_r failure (tm_year out of int range)
166 skip the hostname so the message is handled as valid PRI but without
167 TIMESTAMP or invalid TIMESTAMP (which should force the relay to add the
168 timestamp itself). */
170 __strftime_l (timestamp
, sizeof timestamp
, "%h %e %T ", now_tmp
,
173 #define SYSLOG_HEADER(__pri, __timestamp, __msgoff, pid) \
174 "<%d>%s%n%s%s%.0d%s: ", \
175 __pri, __timestamp, __msgoff, \
176 LogTag == NULL ? __progname : LogTag, \
177 "[" + (pid == 0), pid, "]" + (pid == 0)
179 #define SYSLOG_HEADER_WITHOUT_TS(__pri, __msgoff) \
180 "<%d>: %n", __pri, __msgoff
184 l
= __snprintf (bufs
, sizeof bufs
,
185 SYSLOG_HEADER (pri
, timestamp
, &msgoff
, pid
));
187 l
= __snprintf (bufs
, sizeof bufs
,
188 SYSLOG_HEADER_WITHOUT_TS (pri
, &msgoff
));
197 /* At this point, there is still a chance that we can print the
198 remaining part of the log into bufs and use that. */
200 len
= sizeof (bufs
) - l
;
205 /* We already know that bufs is too small to use for this log message.
206 The next vsnprintf into bufs is used only to calculate the total
207 required buffer length. We will discard bufs contents and allocate
208 an appropriately sized buffer later instead. */
217 /* Restore errno for %m format. */
218 __set_errno (saved_errno
);
220 vl
= __vsnprintf_internal (pos
, len
, fmt
, apc
, mode_flags
);
223 if (vl
< 0 || vl
>= INT_MAX
- l
)
234 buf
= malloc ((bufsize
+ 1) * sizeof (char));
237 /* Tell the cancellation handler to free this buffer. */
242 cl
= __snprintf (buf
, l
+ 1,
243 SYSLOG_HEADER (pri
, timestamp
, &msgoff
, pid
));
245 cl
= __snprintf (buf
, l
+ 1,
246 SYSLOG_HEADER_WITHOUT_TS (pri
, &msgoff
));
252 cl
= __vsnprintf_internal (buf
+ l
, bufsize
- l
+ 1, fmt
, apc
,
262 /* Nothing much to do but emit an error message. */
263 bl
= __snprintf (bufs
, sizeof bufs
,
264 "out of memory[%d]", __getpid ());
265 if (bl
< 0 || bl
>= sizeof bufs
)
274 /* Output to stderr if requested. */
275 if (LogStat
& LOG_PERROR
)
276 __dprintf (STDERR_FILENO
, "%s%s", buf
+ msgoff
,
277 "\n" + (buf
[bufsize
- 1] == '\n'));
279 /* Get connected, output the message to the local logger. */
281 openlog_internal (NULL
, LogStat
| LOG_NDELAY
, LogFacility
);
283 /* If we have a SOCK_STREAM connection, also send ASCII NUL as a record
285 if (LogType
== SOCK_STREAM
)
288 if (!connected
|| __send (LogFile
, buf
, bufsize
, MSG_NOSIGNAL
) < 0)
292 /* Try to reopen the syslog connection. Maybe it went down. */
293 closelog_internal ();
294 openlog_internal (NULL
, LogStat
| LOG_NDELAY
, LogFacility
);
297 if (!connected
|| __send (LogFile
, buf
, bufsize
, MSG_NOSIGNAL
) < 0)
299 closelog_internal (); /* attempt re-open next time */
301 * Output the message to the console; don't worry
302 * about blocking, if console blocks everything will.
303 * Make sure the error reported is the one from the
307 if (LogStat
& LOG_CONS
&&
308 (fd
= __open (_PATH_CONSOLE
, O_WRONLY
| O_NOCTTY
309 | O_CLOEXEC
, 0)) >= 0)
311 __dprintf (fd
, "%s\r\n", buf
+ msgoff
);
318 /* End of critical section. */
319 __libc_cleanup_pop (0);
320 __libc_lock_unlock (syslog_lock
);
326 /* AF_UNIX address of local logger */
327 static const struct sockaddr_un SyslogAddr
=
329 .sun_family
= AF_UNIX
,
330 .sun_path
= _PATH_LOG
334 openlog_internal (const char *ident
, int logstat
, int logfac
)
339 if ((logfac
& ~LOG_FACMASK
) == 0)
340 LogFacility
= logfac
;
347 if (LogStat
& LOG_NDELAY
)
349 LogFile
= __socket (AF_UNIX
, LogType
| SOCK_CLOEXEC
, 0);
354 if (LogFile
!= -1 && !connected
)
356 int old_errno
= errno
;
357 if (__connect (LogFile
, &SyslogAddr
, sizeof (SyslogAddr
)) == -1)
359 int saved_errno
= errno
;
363 __set_errno (old_errno
);
364 if (saved_errno
== EPROTOTYPE
)
366 /* retry with the other type: */
367 LogType
= LogType
== SOCK_DGRAM
? SOCK_STREAM
: SOCK_DGRAM
;
380 openlog (const char *ident
, int logstat
, int logfac
)
382 /* Protect against multiple users and cancellation. */
383 __libc_cleanup_push (cancel_handler
, NULL
);
384 __libc_lock_lock (syslog_lock
);
386 openlog_internal (ident
, logstat
, logfac
);
388 __libc_cleanup_pop (1);
392 closelog_internal (void)
405 /* Protect against multiple users and cancellation. */
406 __libc_cleanup_push (cancel_handler
, NULL
);
407 __libc_lock_lock (syslog_lock
);
409 closelog_internal ();
411 LogType
= SOCK_DGRAM
; /* this is the default */
414 __libc_cleanup_pop (1);
417 /* setlogmask -- set the log mask level */
419 setlogmask (int pmask
)
423 /* Protect against multiple users. */
424 __libc_lock_lock (syslog_lock
);
430 __libc_lock_unlock (syslog_lock
);