xref: /openbsd/usr.sbin/syslogd/log.c (revision 09467b48)
1 /*	$OpenBSD: log.c,v 1.4 2017/04/28 14:52:13 bluhm Exp $	*/
2 
3 /*
4  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
5  * Copyright (c) 2017 Alexander Bluhm <bluhm@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <err.h>
21 #include <errno.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <syslog.h>
26 #include <time.h>
27 
28 #include "log.h"
29 #include "syslogd.h"
30 
31 static int		 verbose;
32 static int		 facility;
33 static const char	*log_procname;
34 static char		*debug_ebuf;
35 static size_t		 debug_length;
36 
37 void
38 log_init(int n_debug, int fac)
39 {
40 	extern char	*__progname;
41 
42 	verbose = n_debug;
43 	facility = fac;
44 	log_procinit(__progname);
45 
46 	if (debug_ebuf == NULL)
47 		if ((debug_ebuf = malloc(ERRBUFSIZE)) == NULL)
48 			err(1, "allocate debug buffer");
49 	debug_ebuf[0] = '\0';
50 	debug_length = 0;
51 
52 	tzset();
53 }
54 
55 void
56 log_procinit(const char *procname)
57 {
58 	if (procname != NULL)
59 		log_procname = procname;
60 }
61 
62 void
63 log_setverbose(int v)
64 {
65 	verbose = v;
66 }
67 
68 int
69 log_getverbose(void)
70 {
71 	return (verbose);
72 }
73 
74 void
75 logit(int pri, const char *fmt, ...)
76 {
77 	va_list	ap;
78 
79 	va_start(ap, fmt);
80 	vlog(pri, fmt, ap);
81 	va_end(ap);
82 }
83 
84 void
85 vlog(int pri, const char *fmt, va_list ap)
86 {
87 	int	 saved_errno = errno;
88 
89 	vlogmsg(facility|pri, log_procname, fmt, ap);
90 
91 	errno = saved_errno;
92 }
93 
94 void
95 log_warn(const char *emsg, ...)
96 {
97 	char	 ebuf[ERRBUFSIZE];
98 	size_t	 l;
99 	va_list	 ap;
100 	int	 saved_errno = errno;
101 
102 	/* best effort to even work in out of memory situations */
103 	if (emsg == NULL)
104 		logit(LOG_ERR, "%s", strerror(saved_errno));
105 	else {
106 		va_start(ap, emsg);
107 		l = vsnprintf(ebuf, sizeof(ebuf), emsg, ap);
108 		if (l < sizeof(ebuf))
109 			snprintf(ebuf+l, sizeof(ebuf)-l, ": %s",
110 			    strerror(saved_errno));
111 		logit(LOG_ERR, "%s", ebuf);
112 		va_end(ap);
113 	}
114 	errno = saved_errno;
115 }
116 
117 void
118 log_warnx(const char *emsg, ...)
119 {
120 	va_list	 ap;
121 
122 	va_start(ap, emsg);
123 	vlog(LOG_ERR, emsg, ap);
124 	va_end(ap);
125 }
126 
127 void
128 log_info(int pri, const char *emsg, ...)
129 {
130 	va_list	 ap;
131 
132 	va_start(ap, emsg);
133 	vlog(pri, emsg, ap);
134 	va_end(ap);
135 }
136 
137 void
138 log_debug(const char *emsg, ...)
139 {
140 	va_list	 ap;
141 	int	 saved_errno;
142 
143 	if (verbose) {
144 		saved_errno = errno;
145 		va_start(ap, emsg);
146 		if (debug_length < ERRBUFSIZE - 1)
147 			vsnprintf(debug_ebuf + debug_length,
148 			    ERRBUFSIZE - debug_length, emsg, ap);
149 		fprintf(stderr, "%s\n", debug_ebuf);
150 		fflush(stderr);
151 		va_end(ap);
152 		errno = saved_errno;
153 	}
154 	debug_ebuf[0] = '\0';
155 	debug_length = 0;
156 }
157 
158 void
159 log_debugadd(const char *emsg, ...)
160 {
161 	size_t	 l;
162 	va_list	 ap;
163 	int	 saved_errno;
164 
165 	if (verbose) {
166 		saved_errno = errno;
167 		va_start(ap, emsg);
168 		if (debug_length < ERRBUFSIZE - 1) {
169 			l = vsnprintf(debug_ebuf + debug_length,
170 			    ERRBUFSIZE - debug_length, emsg, ap);
171 			if (l < ERRBUFSIZE - debug_length)
172 				debug_length += l;
173 			else
174 				debug_length = ERRBUFSIZE - 1;
175 		}
176 		va_end(ap);
177 		errno = saved_errno;
178 	}
179 }
180 
181 static void
182 vfatalc(int error, const char *emsg, va_list ap)
183 {
184 	char		 ebuf[ERRBUFSIZE];
185 	const char	*sep;
186 
187 	if (emsg != NULL) {
188 		(void)vsnprintf(ebuf, sizeof(ebuf), emsg, ap);
189 		sep = ": ";
190 	} else {
191 		ebuf[0] = '\0';
192 		sep = "";
193 	}
194 	if (error)
195 		logit(LOG_CRIT, "fatal in %s: %s%s%s",
196 		    log_procname, ebuf, sep, strerror(error));
197 	else
198 		logit(LOG_CRIT, "fatal in %s%s%s", log_procname, sep, ebuf);
199 }
200 
201 void
202 fatal(const char *emsg, ...)
203 {
204 	va_list	ap;
205 
206 	va_start(ap, emsg);
207 	vfatalc(errno, emsg, ap);
208 	va_end(ap);
209 	die(0);
210 }
211 
212 void
213 fatalx(const char *emsg, ...)
214 {
215 	va_list	ap;
216 
217 	va_start(ap, emsg);
218 	vfatalc(0, emsg, ap);
219 	va_end(ap);
220 	die(0);
221 }
222