xref: /openbsd-src/usr.sbin/snmpd/log.c (revision a9292d2a63fa67dc6b2075a718b776ad5d932d51)
1 /*	$OpenBSD: log.c,v 1.17 2023/12/21 12:43:31 martijn Exp $	*/
2 
3 /*
4  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <stdarg.h>
24 #include <string.h>
25 #include <syslog.h>
26 #include <errno.h>
27 #include <time.h>
28 
29 static int	 debug;
30 static int	 verbose;
31 const char	*log_procname;
32 
33 void	log_init(int, int);
34 void	log_procinit(const char *);
35 void	log_setverbose(int);
36 int	log_getverbose(void);
37 void	log_warn(const char *, ...)
38 	    __attribute__((__format__ (printf, 1, 2)));
39 void	log_warnx(const char *, ...)
40 	    __attribute__((__format__ (printf, 1, 2)));
41 void	log_info(const char *, ...)
42 	    __attribute__((__format__ (printf, 1, 2)));
43 void	log_debug(const char *, ...)
44 	    __attribute__((__format__ (printf, 1, 2)));
45 void	logit(int, const char *, ...)
46 	    __attribute__((__format__ (printf, 2, 3)));
47 void	vlog(int, const char *, va_list)
48 	    __attribute__((__format__ (printf, 2, 0)));
49 __dead void fatal(const char *, ...)
50 	    __attribute__((__format__ (printf, 1, 2)));
51 __dead void fatalx(const char *, ...)
52 	    __attribute__((__format__ (printf, 1, 2)));
53 
54 void
log_init(int n_debug,int facility)55 log_init(int n_debug, int facility)
56 {
57 	extern char	*__progname;
58 
59 	debug = n_debug;
60 	verbose = n_debug;
61 	log_procinit(__progname);
62 
63 	if (!debug)
64 		openlog(__progname, LOG_PID | LOG_NDELAY, facility);
65 
66 	tzset();
67 }
68 
69 void
log_procinit(const char * procname)70 log_procinit(const char *procname)
71 {
72 	if (procname != NULL)
73 		log_procname = procname;
74 }
75 
76 void
log_setverbose(int v)77 log_setverbose(int v)
78 {
79 	verbose = v;
80 }
81 
82 int
log_getverbose(void)83 log_getverbose(void)
84 {
85 	return (verbose);
86 }
87 
88 void
logit(int pri,const char * fmt,...)89 logit(int pri, const char *fmt, ...)
90 {
91 	va_list	ap;
92 
93 	va_start(ap, fmt);
94 	vlog(pri, fmt, ap);
95 	va_end(ap);
96 }
97 
98 void
vlog(int pri,const char * fmt,va_list ap)99 vlog(int pri, const char *fmt, va_list ap)
100 {
101 	char	*nfmt;
102 	int	 saved_errno = errno;
103 
104 	if (debug) {
105 		/* best effort in out of mem situations */
106 		if (asprintf(&nfmt, "%s\n", fmt) == -1) {
107 			vfprintf(stderr, fmt, ap);
108 			fprintf(stderr, "\n");
109 		} else {
110 			vfprintf(stderr, nfmt, ap);
111 			free(nfmt);
112 		}
113 		fflush(stderr);
114 	} else
115 		vsyslog(pri, fmt, ap);
116 
117 	errno = saved_errno;
118 }
119 
120 void
log_warn(const char * emsg,...)121 log_warn(const char *emsg, ...)
122 {
123 	char		*nfmt;
124 	va_list		 ap;
125 	int		 saved_errno = errno;
126 
127 	/* best effort to even work in out of memory situations */
128 	if (emsg == NULL)
129 		logit(LOG_ERR, "%s", strerror(saved_errno));
130 	else {
131 		va_start(ap, emsg);
132 
133 		if (asprintf(&nfmt, "%s: %s", emsg,
134 		    strerror(saved_errno)) == -1) {
135 			/* we tried it... */
136 			vlog(LOG_ERR, emsg, ap);
137 			logit(LOG_ERR, "%s", strerror(saved_errno));
138 		} else {
139 			vlog(LOG_ERR, nfmt, ap);
140 			free(nfmt);
141 		}
142 		va_end(ap);
143 	}
144 
145 	errno = saved_errno;
146 }
147 
148 void
log_warnx(const char * emsg,...)149 log_warnx(const char *emsg, ...)
150 {
151 	va_list	 ap;
152 
153 	va_start(ap, emsg);
154 	vlog(LOG_ERR, emsg, ap);
155 	va_end(ap);
156 }
157 
158 void
log_info(const char * emsg,...)159 log_info(const char *emsg, ...)
160 {
161 	va_list	 ap;
162 
163 	va_start(ap, emsg);
164 	vlog(LOG_INFO, emsg, ap);
165 	va_end(ap);
166 }
167 
168 void
log_debug(const char * emsg,...)169 log_debug(const char *emsg, ...)
170 {
171 	va_list	 ap;
172 
173 	if (verbose > 1) {
174 		va_start(ap, emsg);
175 		vlog(LOG_DEBUG, emsg, ap);
176 		va_end(ap);
177 	}
178 }
179 
180 static void
vfatalc(int code,const char * emsg,va_list ap)181 vfatalc(int code, const char *emsg, va_list ap)
182 {
183 	static char	s[BUFSIZ];
184 	const char	*sep;
185 
186 	if (emsg != NULL) {
187 		(void)vsnprintf(s, sizeof(s), emsg, ap);
188 		sep = ": ";
189 	} else {
190 		s[0] = '\0';
191 		sep = "";
192 	}
193 	if (code)
194 		logit(LOG_CRIT, "%s: %s%s%s",
195 		    log_procname, s, sep, strerror(code));
196 	else
197 		logit(LOG_CRIT, "%s%s%s", log_procname, sep, s);
198 }
199 
200 void
fatal(const char * emsg,...)201 fatal(const char *emsg, ...)
202 {
203 	va_list	ap;
204 
205 	va_start(ap, emsg);
206 	vfatalc(errno, emsg, ap);
207 	va_end(ap);
208 	exit(1);
209 }
210 
211 void
fatalx(const char * emsg,...)212 fatalx(const char *emsg, ...)
213 {
214 	va_list	ap;
215 
216 	va_start(ap, emsg);
217 	vfatalc(0, emsg, ap);
218 	va_end(ap);
219 	exit(1);
220 }
221