xref: /freebsd/sbin/devfs/devfs.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2001, 2002 Dima Dorfman.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 /*
30  * DEVFS control.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/queue.h>
38 
39 #include <assert.h>
40 #include <err.h>
41 #include <fcntl.h>
42 #include <paths.h>
43 #include <stdio.h>
44 #include <stdint.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include "extern.h"
50 
51 int mpfd;
52 
53 static ctbl_t ctbl_main = {
54 	{ "rule",		rule_main },
55 	{ "ruleset",		ruleset_main },
56 	{ NULL,			NULL }
57 };
58 
59 int
60 main(int ac, char **av)
61 {
62 	const char *mountpt;
63 	struct cmd *c;
64 	int ch;
65 
66 	mountpt = NULL;
67 	while ((ch = getopt(ac, av, "m:")) != -1)
68 		switch (ch) {
69 		case 'm':
70 			mountpt = optarg;
71 			break;
72 		default:
73 			usage();
74 		}
75 	ac -= optind;
76 	av += optind;
77 	if (ac < 1)
78 		usage();
79 
80 	if (mountpt == NULL)
81 		mountpt = _PATH_DEV;
82 	mpfd = open(mountpt, O_RDONLY);
83 	if (mpfd == -1)
84 		err(1, "open: %s", mountpt);
85 
86 	for (c = ctbl_main; c->name != NULL; ++c)
87 		if (strcmp(c->name, av[0]) == 0)
88 			exit((*c->handler)(ac, av));
89 	errx(1, "unknown command: %s", av[0]);
90 }
91 
92 /*
93  * Convert an integer to a "number" (ruleset numbers and rule numbers
94  * are 16-bit).  If the conversion is successful, num contains the
95  * integer representation of s and 1 is returned; otherwise, 0 is
96  * returned and num is unchanged.
97  */
98 int
99 atonum(const char *s, uint16_t *num)
100 {
101 	unsigned long ul;
102 	char *cp;
103 
104 	ul = strtoul(s, &cp, 10);
105 	if (ul > UINT16_MAX || *cp != '\0')
106 		return (0);
107 	*num = (uint16_t)ul;
108 	return (1);
109 }
110 
111 /*
112  * Convert user input in ASCII to an integer.
113  */
114 int
115 eatoi(const char *s)
116 {
117 	char *cp;
118 	long l;
119 
120 	l = strtol(s, &cp, 10);
121 	if (l > INT_MAX || *cp != '\0')
122 		errx(1, "error converting to integer: %s", s);
123 	return ((int)l);
124 }
125 
126 /*
127  * As atonum(), but the result of failure is death.
128  */
129 uint16_t
130 eatonum(const char *s)
131 {
132 	uint16_t num;
133 
134 	if (!atonum(s, &num))
135 		errx(1, "error converting to number: %s", s); /* XXX clarify */
136 	return (num);
137 }
138 
139 /*
140  * Read a line from a /FILE/.  If the return value isn't 0, it is the
141  * length of the line, a pointer to which exists in /line/.  It is the
142  * caller's responsibility to free(3) it.  If the return value is 0,
143  * there was an error or we reached EOF, and /line/ is undefined (so,
144  * obviously, the caller shouldn't try to free(3) it).
145  */
146 size_t
147 efgetln(FILE *fp, char **line)
148 {
149 	size_t rv;
150 	char *cp;
151 
152 	cp = fgetln(fp, &rv);
153 	if (cp == NULL) {
154 		*line = NULL;
155 		return (rv);
156 	}
157 	if (cp[rv - 1] == '\n') {
158 		cp[rv - 1] = '\0';
159 		*line = strdup(cp);
160 		if (*line == NULL)
161 			errx(1, "cannot allocate memory");
162 		--rv;
163 	} else {
164 		*line = malloc(rv + 1);
165 		if (*line == NULL)
166 			errx(1, "cannot allocate memory");
167 		memcpy(*line, cp, rv);
168 		(*line)[rv] = '\0';
169 	}
170 	assert(rv == strlen(*line));
171 	return (rv);
172 }
173 
174 struct ptrstq {
175 	STAILQ_ENTRY(ptrstq)	 tq;
176 	void			*ptr;
177 };
178 
179 /*
180  * Create an argument vector from /line/.  The caller must free(3)
181  * /avp/, and /avp[0]/ when the argument vector is no longer
182  * needed unless /acp/ is 0, in which case /avp/ is undefined.
183  * /avp/ is NULL-terminated, so it is actually one longer than /acp/.
184  */
185 void
186 tokenize(const char *line, int *acp, char ***avp)
187 {
188 	static const char *delims = " \t\n";
189 	struct ptrstq *pt;
190 	STAILQ_HEAD(, ptrstq) plist;
191 	char **ap, *cp, *wline, *xcp;
192 
193 	line += strspn(line, delims);
194 	wline = strdup(line);
195 	if (wline == NULL)
196 		errx(1, "cannot allocate memory");
197 
198 	STAILQ_INIT(&plist);
199 	for (xcp = wline, *acp = 0;
200 	     (cp = strsep(&xcp, delims)) != NULL;)
201 		if (*cp != '\0') {
202 			pt = calloc(1, sizeof(*pt));
203 			if (pt == NULL)
204 				errx(1, "cannot allocate memory");
205 			pt->ptr = cp;
206 			STAILQ_INSERT_TAIL(&plist, pt, tq);
207 			++*acp;
208 		}
209 	if (*acp == 0)
210 		return;
211 	assert(STAILQ_FIRST(&plist)->ptr == wline);
212 	*avp = malloc(sizeof(**avp) * (*acp + 1));
213 	if (*avp == NULL)
214 		errx(1, "cannot allocate memory");
215 	for (ap = *avp; !STAILQ_EMPTY(&plist);) {
216 		pt = STAILQ_FIRST(&plist);
217 		*ap = pt->ptr;
218 		++ap;
219 		assert(ap <= *avp + (*acp));
220 		STAILQ_REMOVE_HEAD(&plist, tq);
221 		free(pt);
222 	}
223 	*ap = NULL;
224 }
225 
226 void
227 usage(void)
228 {
229 
230 	fprintf(stderr, "usage: %s\n%s\n",
231 	    "\tdevfs [-m mount-point] [-s ruleset] rule ...",
232 	    "\tdevfs [-m mount-point] ruleset ...");
233 	exit(1);
234 }
235