xref: /illumos-gate/usr/src/lib/lib9p/common/log.c (revision ddb365bfc9e868ad24ccdcb0dc91af18b10df082)
1 /*
2  * Copyright 2016 Jakub Klama <jceel@FreeBSD.org>
3  * All rights reserved
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted providing that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
18  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
23  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  *
26  */
27 
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <stdarg.h>
31 #include <string.h>
32 #include "log.h"
33 
34 static const char *l9p_log_level_names[] = {
35 	"DEBUG",
36 	"INFO",
37 	"WARN",
38 	"ERROR"
39 };
40 
41 void
42 l9p_logf(enum l9p_log_level level, const char *func, const char *fmt, ...)
43 {
44 	const char *dest = NULL;
45 	static FILE *stream = NULL;
46 	va_list ap;
47 
48 	if (stream == NULL) {
49 		dest = getenv("LIB9P_LOGGING");
50 		if (dest == NULL)
51 			return;
52 		else if (!strcmp(dest, "stderr"))
53 			stream = stderr;
54 		else {
55 			stream = fopen(dest, "a");
56 			if (stream == NULL)
57 				return;
58 		}
59 	}
60 
61 	va_start(ap, fmt);
62 	fprintf(stream, "[%s]\t %s: ", l9p_log_level_names[level], func);
63 	vfprintf(stream, fmt, ap);
64 	fprintf(stream, "\n");
65 	fflush(stream);
66 	va_end(ap);
67 }
68