xref: /freebsd/usr.bin/getconf/getconf.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
1 /*
2  * Copyright 2000 Massachusetts Institute of Technology
3  *
4  * Permission to use, copy, modify, and distribute this software and
5  * its documentation for any purpose and without fee is hereby
6  * granted, provided that both the above copyright notice and this
7  * permission notice appear in all copies, that both the above
8  * copyright notice and this permission notice appear in all
9  * supporting documentation, and that the name of M.I.T. not be used
10  * in advertising or publicity pertaining to distribution of the
11  * software without specific, written prior permission.  M.I.T. makes
12  * no representations about the suitability of this software for any
13  * purpose.  It is provided "as is" without express or implied
14  * warranty.
15  *
16  * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
17  * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
18  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
20  * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
23  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
26  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #include <sys/types.h>
33 
34 #include <err.h>
35 #include <errno.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <sysexits.h>
39 #include <unistd.h>
40 
41 #include "getconf.h"
42 
43 static void	do_confstr(const char *name, int key);
44 static void	do_sysconf(const char *name, int key);
45 static void	do_pathconf(const char *name, int key, const char *path);
46 
47 static void
48 usage(void)
49 {
50 	fprintf(stderr, "usage:\n"
51 		"\tgetconf [-v prog_model] system_var\n"
52 		"\tgetconf [-v prog_model] path_var pathname\n");
53 	exit(EX_USAGE);
54 }
55 
56 int
57 main(int argc, char **argv)
58 {
59 	int c;
60 	const char *name, *vflag;
61 	int key;
62 
63 	vflag = 0;
64 
65 	while ((c = getopt(argc, argv, "v:")) != -1) {
66 		switch (c) {
67 		case 'v':
68 			vflag = optarg;
69 			break;
70 
71 		default:
72 			usage();
73 		}
74 	}
75 
76 	if (vflag)
77 		warnx("-v %s ignored", vflag);
78 
79 	/* No arguments... */
80 	if ((name = argv[optind]) == 0)
81 		usage();
82 
83 	if (argv[optind + 1] == 0) { /* confstr or sysconf */
84 		key = find_confstr(name);
85 		if (key >= 0) {
86 			do_confstr(name, key);
87 		} else {
88 			key = find_sysconf(name);
89 			if (key >= 0)
90 				do_sysconf(name, key);
91 			else
92 				errx(EX_USAGE,
93 				     "no such configuration parameter `%s'",
94 				     name);
95 		}
96 	} else {
97 		key = find_pathconf(name);
98 		if (key >= 0)
99 			do_pathconf(name, key, argv[optind + 1]);
100 		else
101 			errx(EX_USAGE,
102 			     "no such path configuration parameter `%s'",
103 			     name);
104 	}
105 	return 0;
106 }
107 
108 static void
109 do_confstr(const char *name, int key)
110 {
111 	char *buf;
112 	size_t len;
113 
114 	len = confstr(key, 0, 0);
115 	if (len < 0)
116 		err(EX_OSERR, "confstr: %s", name);
117 
118 	if (len == 0) {
119 		printf("undefined\n");
120 	} else {
121 		buf = alloca(len);
122 		confstr(key, buf, len);
123 		printf("%s\n", buf);
124 	}
125 }
126 
127 static void
128 do_sysconf(const char *name, int key)
129 {
130 	long value;
131 
132 	errno = 0;
133 	value = sysconf(key);
134 	if (value == -1 && errno != 0)
135 		err(EX_OSERR, "sysconf: %s", name);
136 	else if (value == -1)
137 		printf("undefined\n");
138 	else
139 		printf("%ld\n", value);
140 }
141 
142 static void
143 do_pathconf(const char *name, int key, const char *path)
144 {
145 	long value;
146 
147 	errno = 0;
148 	value = pathconf(path, key);
149 	if (value == -1 && errno != 0)
150 		err(EX_OSERR, "pathconf: %s", name);
151 	else if (value == -1)
152 		printf("undefined\n");
153 	else
154 		printf("%ld\n", value);
155 }
156