1 /*	$OpenBSD: log.c,v 1.20 2017/03/21 12:06:56 bluhm 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 <stdio.h>
20 #include <stdlib.h>
21 #include <stdarg.h>
22 #include <string.h>
23 #include <syslog.h>
24 #include <errno.h>
25 #include <time.h>
26 
27 static int	 debug;
28 static int	 verbose;
29 const char	*log_procname;
30 
31 void	log_init(int, int);
32 void	log_procinit(const char *);
33 void	log_setverbose(int);
34 int	log_getverbose(void);
35 void	log_warn(const char *, ...)
36 	    __attribute__((__format__ (printf, 1, 2)));
37 void	log_warnx(const char *, ...)
38 	    __attribute__((__format__ (printf, 1, 2)));
39 void	log_info(const char *, ...)
40 	    __attribute__((__format__ (printf, 1, 2)));
41 void	log_debug(const char *, ...)
42 	    __attribute__((__format__ (printf, 1, 2)));
43 void	logit(int, const char *, ...)
44 	    __attribute__((__format__ (printf, 2, 3)));
45 void	vlog(int, const char *, va_list)
46 	    __attribute__((__format__ (printf, 2, 0)));
47 __dead void fatal(const char *, ...)
48 	    __attribute__((__format__ (printf, 1, 2)));
49 __dead void fatalx(const char *, ...)
50 	    __attribute__((__format__ (printf, 1, 2)));
51 
52 void
53 log_init(int n_debug, int facility)
54 {
55 	extern char	*__progname;
56 
57 	debug = n_debug;
58 	verbose = n_debug;
59 	log_procinit(__progname);
60 
61 	if (!debug)
62 		openlog(__progname, LOG_PID | LOG_NDELAY, facility);
63 
64 	tzset();
65 }
66 
67 void
68 log_procinit(const char *procname)
69 {
70 	if (procname != NULL)
71 		log_procname = procname;
72 }
73 
74 void
75 log_setverbose(int v)
76 {
77 	verbose = v;
78 }
79 
80 int
81 log_getverbose(void)
82 {
83 	return (verbose);
84 }
85 
86 void
87 logit(int pri, const char *fmt, ...)
88 {
89 	va_list	ap;
90 
91 	va_start(ap, fmt);
92 	vlog(pri, fmt, ap);
93 	va_end(ap);
94 }
95 
96 void
97 vlog(int pri, const char *fmt, va_list ap)
98 {
99 	char	*nfmt;
100 	int	 saved_errno = errno;
101 
102 	if (debug) {
103 		/* best effort in out of mem situations */
104 		if (asprintf(&nfmt, "%s\n", fmt) == -1) {
105 			vfprintf(stderr, fmt, ap);
106 			fprintf(stderr, "\n");
107 		} else {
108 			vfprintf(stderr, nfmt, ap);
109 			free(nfmt);
110 		}
111 		fflush(stderr);
112 	} else
113 		vsyslog(pri, fmt, ap);
114 
115 	errno = saved_errno;
116 }
117 
118 void
119 log_warn(const char *emsg, ...)
120 {
121 	char		*nfmt;
122 	va_list		 ap;
123 	int		 saved_errno = errno;
124 
125 	/* best effort to even work in out of memory situations */
126 	if (emsg == NULL)
127 		logit(LOG_ERR, "%s", strerror(saved_errno));
128 	else {
129 		va_start(ap, emsg);
130 
131 		if (asprintf(&nfmt, "%s: %s", emsg,
132 		    strerror(saved_errno)) == -1) {
133 			/* we tried it... */
134 			vlog(LOG_ERR, emsg, ap);
135 			logit(LOG_ERR, "%s", strerror(saved_errno));
136 		} else {
137 			vlog(LOG_ERR, nfmt, ap);
138 			free(nfmt);
139 		}
140 		va_end(ap);
141 	}
142 
143 	errno = saved_errno;
144 }
145 
146 void
147 log_warnx(const char *emsg, ...)
148 {
149 	va_list	 ap;
150 
151 	va_start(ap, emsg);
152 	vlog(LOG_ERR, emsg, ap);
153 	va_end(ap);
154 }
155 
156 void
157 log_info(const char *emsg, ...)
158 {
159 	va_list	 ap;
160 
161 	va_start(ap, emsg);
162 	vlog(LOG_INFO, emsg, ap);
163 	va_end(ap);
164 }
165 
166 void
167 log_debug(const char *emsg, ...)
168 {
169 	va_list	 ap;
170 
171 	if (verbose > 1) {
172 		va_start(ap, emsg);
173 		vlog(LOG_DEBUG, emsg, ap);
174 		va_end(ap);
175 	}
176 }
177 
178 static void
179 vfatalc(int code, const char *emsg, va_list ap)
180 {
181 	static char	s[BUFSIZ];
182 	const char	*sep;
183 
184 	if (emsg != NULL) {
185 		(void)vsnprintf(s, sizeof(s), emsg, ap);
186 		sep = ": ";
187 	} else {
188 		s[0] = '\0';
189 		sep = "";
190 	}
191 	if (code)
192 		logit(LOG_CRIT, "%s: %s%s%s",
193 		    log_procname, s, sep, strerror(code));
194 	else
195 		logit(LOG_CRIT, "%s%s%s", log_procname, sep, s);
196 }
197 
198 void
199 fatal(const char *emsg, ...)
200 {
201 	va_list	ap;
202 
203 	va_start(ap, emsg);
204 	vfatalc(errno, emsg, ap);
205 	va_end(ap);
206 	exit(1);
207 }
208 
209 void
210 fatalx(const char *emsg, ...)
211 {
212 	va_list	ap;
213 
214 	va_start(ap, emsg);
215 	vfatalc(0, emsg, ap);
216 	va_end(ap);
217 	exit(1);
218 }