xref: /netbsd-src/lib/libc/gen/syslog.c (revision 76c7fc5f6b13ed0b1508e6b313e88e59977ed78e)
1 /*	$NetBSD: syslog.c,v 1.58 2017/01/12 18:16:52 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1983, 1988, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)syslog.c	8.5 (Berkeley) 4/29/95";
36 #else
37 __RCSID("$NetBSD: syslog.c,v 1.58 2017/01/12 18:16:52 christos Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include "namespace.h"
42 #include <sys/types.h>
43 #include <sys/param.h>
44 #include <sys/socket.h>
45 #include <sys/syslog.h>
46 #include <sys/uio.h>
47 #include <sys/un.h>
48 #include <netdb.h>
49 
50 #include <errno.h>
51 #include <stdio.h>
52 #include <fcntl.h>
53 #include <paths.h>
54 #include <stdarg.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <time.h>
59 #include <unistd.h>
60 
61 #include "syslog_private.h"
62 #include "reentrant.h"
63 #include "extern.h"
64 
65 #ifdef __weak_alias
66 __weak_alias(syslog,_syslog)
67 __weak_alias(vsyslog,_vsyslog)
68 __weak_alias(syslogp,_syslogp)
69 __weak_alias(vsyslogp,_vsyslogp)
70 __weak_alias(closelog,_closelog)
71 __weak_alias(openlog,_openlog)
72 __weak_alias(setlogmask,_setlogmask)
73 #endif
74 
75 static struct syslog_data _syslog_data = SYSLOG_DATA_INIT;
76 
77 #ifdef _REENTRANT
78 static mutex_t	syslog_mutex = MUTEX_INITIALIZER;
79 #endif
80 
81 static size_t
82 timefun(char *p, size_t tbuf_left)
83 {
84 	struct timeval tv;
85 	time_t now;
86 	struct tm tmnow;
87 	size_t prlen;
88 	char *op = p;
89 
90 	if (gettimeofday(&tv, NULL) == -1)
91 		return snprintf_ss(p, tbuf_left, "-");
92 
93 	/* strftime() implies tzset(), localtime_r() doesn't. */
94 	tzset();
95 	now = (time_t) tv.tv_sec;
96 	localtime_r(&now, &tmnow);
97 
98 	prlen = strftime(p, tbuf_left, "%FT%T", &tmnow);
99 	DEC();
100 	prlen = snprintf(p, tbuf_left, ".%06ld", (long)tv.tv_usec);
101 	DEC();
102 	prlen = strftime(p, tbuf_left-1, "%z", &tmnow);
103 	/* strftime gives eg. "+0200", but we need "+02:00" */
104 	if (prlen == 5) {
105 		p[prlen+1] = p[prlen];
106 		p[prlen]   = p[prlen-1];
107 		p[prlen-1] = p[prlen-2];
108 		p[prlen-2] = ':';
109 		prlen += 1;
110 	}
111 	DEC();
112 	return (size_t)(p - op);
113 }
114 
115 static int
116 lock(const struct syslog_data *data)
117 {
118 	int rv = data == &_syslog_data;
119 	if (rv)
120 		mutex_lock(&syslog_mutex);
121 	return rv;
122 }
123 
124 static int
125 unlock(const struct syslog_data *data)
126 {
127 	int rv = data == &_syslog_data;
128 	if (rv)
129 		mutex_unlock(&syslog_mutex);
130 	return rv;
131 }
132 
133 static struct syslog_fun _syslog_fun = {
134 	timefun,
135 	strerror_r,
136 	vsnprintf,
137 	lock,
138 	unlock,
139 };
140 
141 void
142 openlog(const char *ident, int logstat, int logfac)
143 {
144 	openlog_r(ident, logstat, logfac, &_syslog_data);
145 }
146 
147 void
148 closelog(void)
149 {
150 	closelog_r(&_syslog_data);
151 }
152 
153 /* setlogmask -- set the log mask level */
154 int
155 setlogmask(int pmask)
156 {
157 	return setlogmask_r(pmask, &_syslog_data);
158 }
159 
160 void
161 openlog_r(const char *ident, int logstat, int logfac, struct syslog_data *data)
162 {
163 	lock(data);
164 	_openlog_unlocked_r(ident, logstat, logfac, data);
165 	unlock(data);
166 }
167 
168 void
169 closelog_r(struct syslog_data *data)
170 {
171 	lock(data);
172 	_closelog_unlocked_r(data);
173 	data->log_tag = NULL;
174 	unlock(data);
175 }
176 
177 /*
178  * syslog, vsyslog --
179  *	print message on log file; output is intended for syslogd(8).
180  */
181 void
182 syslog(int pri, const char *fmt, ...)
183 {
184 	va_list ap;
185 
186 	va_start(ap, fmt);
187 	_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data, NULL, NULL, fmt, ap);
188 	va_end(ap);
189 }
190 
191 void
192 vsyslog(int pri, const char *fmt, va_list ap)
193 {
194 	_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data, NULL, NULL, fmt, ap);
195 }
196 
197 /*
198  * syslogp, vsyslogp --
199  *	like syslog but take additional arguments for MSGID and SD
200  */
201 void
202 syslogp(int pri, const char *msgid, const char *sdfmt, const char *msgfmt, ...)
203 {
204 	va_list ap;
205 
206 	va_start(ap, msgfmt);
207 	_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data,
208 	    msgid, sdfmt, msgfmt, ap);
209 	va_end(ap);
210 }
211 
212 void
213 vsyslogp(int pri, const char *msgid, const char *sdfmt, const char *msgfmt,
214     va_list ap)
215 {
216 	_vxsyslogp_r(pri, &_syslog_fun, &_syslog_data,
217 	    msgid, sdfmt, msgfmt, ap);
218 }
219 
220 void
221 vsyslogp_r(int pri, struct syslog_data *data, const char *msgid,
222     const char *sdfmt, const char *msgfmt, va_list ap)
223 {
224 	_vxsyslogp_r(pri, &_syslog_fun, data, msgid, sdfmt, msgfmt, ap);
225 }
226 
227 void
228 syslog_r(int pri, struct syslog_data *data, const char *fmt, ...)
229 {
230 	va_list ap;
231 
232 	va_start(ap, fmt);
233 	_vxsyslogp_r(pri, &_syslog_fun, data, NULL, NULL, fmt, ap);
234 	va_end(ap);
235 }
236 
237 void
238 syslogp_r(int pri, struct syslog_data *data, const char *msgid,
239 	const char *sdfmt, const char *msgfmt, ...)
240 {
241 	va_list ap;
242 
243 	va_start(ap, msgfmt);
244 	_vxsyslogp_r(pri, &_syslog_fun, data, msgid, sdfmt, msgfmt, ap);
245 	va_end(ap);
246 }
247 
248 void
249 vsyslog_r(int pri, struct syslog_data *data, const char *fmt, va_list ap)
250 {
251 	_vxsyslogp_r(pri, &_syslog_fun, data, NULL, NULL, fmt, ap);
252 }
253