xref: /openbsd-src/usr.bin/getconf/getconf.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: getconf.c,v 1.11 2008/11/08 01:29:10 chl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1996 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by J.T. Conklin.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by Winning Strategies, Inc.
21  * 4. The name of the author may not be used to endorse or promote products
22  *    derived from this software without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /*
37  * POSIX.2 getconf utility
38  *
39  * Written by:
40  *	J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
41  */
42 
43 #ifndef lint
44 static char rcsid[] = "$OpenBSD: getconf.c,v 1.11 2008/11/08 01:29:10 chl Exp $";
45 #endif /* not lint */
46 
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 #include <limits.h>
51 #include <locale.h>
52 #include <unistd.h>
53 #include <err.h>
54 #include <errno.h>
55 
56 static void usage(void);
57 
58 struct conf_variable
59 {
60   const char *name;
61   enum { SYSCONF, CONFSTR, PATHCONF, CONSTANT } type;
62   long value;
63 };
64 
65 const struct conf_variable conf_table[] =
66 {
67   { "PATH",			CONFSTR,	_CS_PATH		},
68 
69   /* Utility Limit Minimum Values */
70   { "POSIX2_BC_BASE_MAX",	CONSTANT,	_POSIX2_BC_BASE_MAX	},
71   { "POSIX2_BC_DIM_MAX",	CONSTANT,	_POSIX2_BC_DIM_MAX	},
72   { "POSIX2_BC_SCALE_MAX",	CONSTANT,	_POSIX2_BC_SCALE_MAX	},
73   { "POSIX2_BC_STRING_MAX",	CONSTANT,	_POSIX2_BC_STRING_MAX	},
74   { "POSIX2_COLL_WEIGHTS_MAX",	CONSTANT,	_POSIX2_COLL_WEIGHTS_MAX },
75   { "POSIX2_EXPR_NEST_MAX",	CONSTANT,	_POSIX2_EXPR_NEST_MAX	},
76   { "POSIX2_LINE_MAX",		CONSTANT,	_POSIX2_LINE_MAX	},
77   { "POSIX2_RE_DUP_MAX",	CONSTANT,	_POSIX2_RE_DUP_MAX	},
78   { "POSIX2_VERSION",		CONSTANT,	_POSIX2_VERSION		},
79 
80   /* POSIX.1 Minimum Values */
81   { "_POSIX_ARG_MAX",		CONSTANT,	_POSIX_ARG_MAX		},
82   { "_POSIX_CHILD_MAX",		CONSTANT,	_POSIX_CHILD_MAX	},
83   { "_POSIX_LINK_MAX",		CONSTANT,	_POSIX_LINK_MAX		},
84   { "_POSIX_MAX_CANON",		CONSTANT,	_POSIX_MAX_CANON	},
85   { "_POSIX_MAX_INPUT",		CONSTANT,	_POSIX_MAX_INPUT	},
86   { "_POSIX_NAME_MAX",		CONSTANT,	_POSIX_NAME_MAX		},
87   { "_POSIX_NGROUPS_MAX",	CONSTANT,	_POSIX_NGROUPS_MAX	},
88   { "_POSIX_OPEN_MAX",		CONSTANT,	_POSIX_OPEN_MAX		},
89   { "_POSIX_PATH_MAX",		CONSTANT,	_POSIX_PATH_MAX		},
90   { "_POSIX_PIPE_BUF",		CONSTANT,	_POSIX_PIPE_BUF		},
91   { "_POSIX_SSIZE_MAX",		CONSTANT,	_POSIX_SSIZE_MAX	},
92   { "_POSIX_STREAM_MAX",	CONSTANT,	_POSIX_STREAM_MAX	},
93   { "_POSIX_TZNAME_MAX",	CONSTANT,	_POSIX_TZNAME_MAX	},
94 
95   /* Symbolic Utility Limits */
96   { "BC_BASE_MAX",		SYSCONF,	_SC_BC_BASE_MAX		},
97   { "BC_DIM_MAX",		SYSCONF,	_SC_BC_DIM_MAX		},
98   { "BC_SCALE_MAX",		SYSCONF,	_SC_BC_SCALE_MAX	},
99   { "BC_STRING_MAX",		SYSCONF,	_SC_BC_STRING_MAX	},
100   { "COLL_WEIGHTS_MAX",		SYSCONF,	_SC_COLL_WEIGHTS_MAX	},
101   { "EXPR_NEST_MAX",		SYSCONF,	_SC_EXPR_NEST_MAX	},
102   { "LINE_MAX",			SYSCONF,	_SC_LINE_MAX		},
103   { "RE_DUP_MAX",		SYSCONF,	_SC_RE_DUP_MAX		},
104 
105   /* Optional Facility Configuration Values */
106 #if 0
107   { "POSIX2_C_BIND",		SYSCONF,	???			},
108 #endif
109   { "POSIX2_C_DEV",		SYSCONF,	_SC_2_C_DEV		},
110   { "POSIX2_CHAR_TERM",		SYSCONF,	_SC_2_CHAR_TERM		},
111   { "POSIX2_FORT_DEV",		SYSCONF,	_SC_2_FORT_DEV		},
112   { "POSIX2_FORT_RUN",		SYSCONF,	_SC_2_FORT_RUN		},
113   { "POSIX2_LOCALEDEF",		SYSCONF,	_SC_2_LOCALEDEF		},
114   { "POSIX2_SW_DEV",		SYSCONF,	_SC_2_SW_DEV		},
115   { "POSIX2_UPE",		SYSCONF,	_SC_2_UPE		},
116 
117   /* POSIX.1 Configurable System Variables */
118   { "ARG_MAX",			SYSCONF,	_SC_ARG_MAX 		},
119   { "CHILD_MAX",		SYSCONF,	_SC_CHILD_MAX		},
120   { "CLK_TCK",			SYSCONF,	_SC_CLK_TCK		},
121   { "NGROUPS_MAX",		SYSCONF,	_SC_NGROUPS_MAX		},
122   { "OPEN_MAX",			SYSCONF,	_SC_OPEN_MAX		},
123   { "STREAM_MAX",		SYSCONF,	_SC_STREAM_MAX		},
124   { "TZNAME_MAX",		SYSCONF,	_SC_TZNAME_MAX		},
125   { "_POSIX_JOB_CONTROL",	SYSCONF,	_SC_JOB_CONTROL 	},
126   { "_POSIX_SAVED_IDS",		SYSCONF,	_SC_SAVED_IDS		},
127   { "_POSIX_VERSION",		SYSCONF,	_SC_VERSION		},
128 
129   { "LINK_MAX",			PATHCONF,	_PC_LINK_MAX		},
130   { "MAX_CANON",		PATHCONF,	_PC_MAX_CANON		},
131   { "MAX_INPUT",		PATHCONF,	_PC_MAX_INPUT		},
132   { "NAME_MAX",			PATHCONF,	_PC_NAME_MAX		},
133   { "PATH_MAX",			PATHCONF,	_PC_PATH_MAX		},
134   { "PIPE_BUF",			PATHCONF,	_PC_PIPE_BUF		},
135   { "_POSIX_CHOWN_RESTRICTED",	PATHCONF,	_PC_CHOWN_RESTRICTED	},
136   { "_POSIX_NO_TRUNC",		PATHCONF,	_PC_NO_TRUNC		},
137   { "_POSIX_VDISABLE",		PATHCONF,	_PC_VDISABLE		},
138 
139   { NULL }
140 };
141 
142 
143 int
144 main(int argc, char *argv[])
145 {
146 	int ch;
147 	const struct conf_variable *cp;
148 
149 	long val;
150 	size_t slen;
151 	char * sval;
152 
153 	setlocale(LC_ALL, "");
154 
155 	while ((ch = getopt(argc, argv, "")) != -1) {
156 		switch (ch) {
157 		case '?':
158 		default:
159 			usage();
160 		}
161 	}
162 	argc -= optind;
163 	argv += optind;
164 
165 	if (argc < 1 || argc > 2) {
166 		usage();
167 		/* NOTREACHED */
168 	}
169 
170 	for (cp = conf_table; cp->name != NULL; cp++) {
171 		if (strcmp(*argv, cp->name) == 0)
172 			break;
173 	}
174 	if (cp->name == NULL) {
175 		errx(1, "%s: unknown variable", *argv);
176 		/* NOTREACHED */
177 	}
178 
179 	if (cp->type == PATHCONF) {
180 		if (argc != 2) usage();
181 	} else {
182 		if (argc != 1) usage();
183 	}
184 
185 	switch (cp->type) {
186 	case CONSTANT:
187 		printf("%ld\n", cp->value);
188 		break;
189 
190 	case CONFSTR:
191 		errno = 0;
192 		slen = confstr (cp->value, (char *) 0, (size_t) 0);
193 
194 		if (slen == 0 || slen == (size_t)-1) {
195 			if (errno)
196 				err(1, "%ld", cp->value);
197 			else
198 				errx(1, "%ld", cp->value);
199 		}
200 		if ((sval = malloc(slen)) == NULL)
201 			err(1, NULL);
202 
203 		confstr(cp->value, sval, slen);
204 		printf("%s\n", sval);
205 		break;
206 
207 	case SYSCONF:
208 		errno = 0;
209 		if ((val = sysconf(cp->value)) == -1) {
210 			if (errno != 0) {
211 				err(1, NULL);
212 				/* NOTREACHED */
213 			}
214 
215 			printf ("undefined\n");
216 		} else {
217 			printf("%ld\n", val);
218 		}
219 		break;
220 
221 	case PATHCONF:
222 		errno = 0;
223 		if ((val = pathconf(argv[1], cp->value)) == -1) {
224 			if (errno != 0) {
225 				err(1, "%s", argv[1]);
226 				/* NOTREACHED */
227 			}
228 
229 			printf ("undefined\n");
230 		} else {
231 			printf ("%ld\n", val);
232 		}
233 		break;
234 	}
235 
236 	exit (ferror(stdout));
237 }
238 
239 
240 static void
241 usage(void)
242 {
243 	extern char *__progname;
244 
245 	(void)fprintf(stderr, "usage: %s name [pathname]\n", __progname);
246 	exit(1);
247 }
248