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