xref: /freebsd/sbin/devfs/devfs.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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/param.h>
34 #include <sys/queue.h>
35 
36 #include <assert.h>
37 #include <err.h>
38 #include <fcntl.h>
39 #include <paths.h>
40 #include <stdio.h>
41 #include <stdint.h>
42 #include <stdlib.h>
43 #include <string.h>
44 #include <unistd.h>
45 
46 #include "extern.h"
47 
48 int mpfd;
49 
50 static ctbl_t ctbl_main = {
51 	{ "rule",		rule_main },
52 	{ "ruleset",		ruleset_main },
53 	{ NULL,			NULL }
54 };
55 
56 int
57 main(int ac, char **av)
58 {
59 	const char *mountpt;
60 	struct cmd *c;
61 	int ch;
62 
63 	mountpt = NULL;
64 	while ((ch = getopt(ac, av, "m:")) != -1)
65 		switch (ch) {
66 		case 'm':
67 			mountpt = optarg;
68 			break;
69 		default:
70 			usage();
71 		}
72 	ac -= optind;
73 	av += optind;
74 	if (ac < 1)
75 		usage();
76 
77 	if (mountpt == NULL)
78 		mountpt = _PATH_DEV;
79 	mpfd = open(mountpt, O_RDONLY);
80 	if (mpfd == -1)
81 		err(1, "open: %s", mountpt);
82 
83 	for (c = ctbl_main; c->name != NULL; ++c)
84 		if (strcmp(c->name, av[0]) == 0)
85 			exit((*c->handler)(ac, av));
86 	errx(1, "unknown command: %s", av[0]);
87 }
88 
89 /*
90  * Convert an integer to a "number" (ruleset numbers and rule numbers
91  * are 16-bit).  If the conversion is successful, num contains the
92  * integer representation of s and 1 is returned; otherwise, 0 is
93  * returned and num is unchanged.
94  */
95 int
96 atonum(const char *s, uint16_t *num)
97 {
98 	unsigned long ul;
99 	char *cp;
100 
101 	ul = strtoul(s, &cp, 10);
102 	if (ul > UINT16_MAX || *cp != '\0')
103 		return (0);
104 	*num = (uint16_t)ul;
105 	return (1);
106 }
107 
108 /*
109  * Convert user input in ASCII to an integer.
110  */
111 int
112 eatoi(const char *s)
113 {
114 	char *cp;
115 	long l;
116 
117 	l = strtol(s, &cp, 10);
118 	if (l > INT_MAX || *cp != '\0')
119 		errx(1, "error converting to integer: %s", s);
120 	return ((int)l);
121 }
122 
123 /*
124  * As atonum(), but the result of failure is death.
125  */
126 uint16_t
127 eatonum(const char *s)
128 {
129 	uint16_t num;
130 
131 	if (!atonum(s, &num))
132 		errx(1, "error converting to number: %s", s); /* XXX clarify */
133 	return (num);
134 }
135 
136 /*
137  * Read a line from a /FILE/.  If the return value isn't 0, it is the
138  * length of the line, a pointer to which exists in /line/.  It is the
139  * caller's responsibility to free(3) it.  If the return value is 0,
140  * there was an error or we reached EOF, and /line/ is undefined (so,
141  * obviously, the caller shouldn't try to free(3) it).
142  */
143 size_t
144 efgetln(FILE *fp, char **line)
145 {
146 	size_t rv;
147 	char *cp;
148 
149 	cp = fgetln(fp, &rv);
150 	if (cp == NULL) {
151 		*line = NULL;
152 		return (rv);
153 	}
154 	if (cp[rv - 1] == '\n') {
155 		cp[rv - 1] = '\0';
156 		*line = strdup(cp);
157 		if (*line == NULL)
158 			errx(1, "cannot allocate memory");
159 		--rv;
160 	} else {
161 		*line = malloc(rv + 1);
162 		if (*line == NULL)
163 			errx(1, "cannot allocate memory");
164 		memcpy(*line, cp, rv);
165 		(*line)[rv] = '\0';
166 	}
167 	assert(rv == strlen(*line));
168 	return (rv);
169 }
170 
171 struct ptrstq {
172 	STAILQ_ENTRY(ptrstq)	 tq;
173 	void			*ptr;
174 };
175 
176 /*
177  * Create an argument vector from /line/.  The caller must free(3)
178  * /avp/, and /avp[0]/ when the argument vector is no longer
179  * needed unless /acp/ is 0, in which case /avp/ is undefined.
180  * /avp/ is NULL-terminated, so it is actually one longer than /acp/.
181  */
182 void
183 tokenize(const char *line, int *acp, char ***avp)
184 {
185 	static const char *delims = " \t\n";
186 	struct ptrstq *pt;
187 	STAILQ_HEAD(, ptrstq) plist;
188 	char **ap, *cp, *wline, *xcp;
189 
190 	line += strspn(line, delims);
191 	wline = strdup(line);
192 	if (wline == NULL)
193 		errx(1, "cannot allocate memory");
194 
195 	STAILQ_INIT(&plist);
196 	for (xcp = wline, *acp = 0;
197 	     (cp = strsep(&xcp, delims)) != NULL;)
198 		if (*cp != '\0') {
199 			pt = calloc(1, sizeof(*pt));
200 			if (pt == NULL)
201 				errx(1, "cannot allocate memory");
202 			pt->ptr = cp;
203 			STAILQ_INSERT_TAIL(&plist, pt, tq);
204 			++*acp;
205 		}
206 	if (*acp == 0)
207 		return;
208 	assert(STAILQ_FIRST(&plist)->ptr == wline);
209 	*avp = malloc(sizeof(**avp) * (*acp + 1));
210 	if (*avp == NULL)
211 		errx(1, "cannot allocate memory");
212 	for (ap = *avp; !STAILQ_EMPTY(&plist);) {
213 		pt = STAILQ_FIRST(&plist);
214 		*ap = pt->ptr;
215 		++ap;
216 		assert(ap <= *avp + (*acp));
217 		STAILQ_REMOVE_HEAD(&plist, tq);
218 		free(pt);
219 	}
220 	*ap = NULL;
221 }
222 
223 void
224 usage(void)
225 {
226 
227 	fprintf(stderr, "usage: %s\n%s\n",
228 	    "\tdevfs [-m mount-point] rule [-s ruleset] ...",
229 	    "\tdevfs [-m mount-point] ruleset ...");
230 	exit(1);
231 }
232