xref: /netbsd-src/usr.sbin/fstyp/fstyp.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: fstyp.c,v 1.2 2018/01/09 10:47:57 martin Exp $	*/
2 
3 /*-
4  * Copyright (c) 2017 The NetBSD Foundation, Inc.
5  * Copyright (c) 2016 The DragonFly Project
6  * Copyright (c) 2014 The FreeBSD Foundation
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Tomohiro Kusumi <kusumi.tomohiro@gmail.com>.
11  *
12  * This software was developed by Edward Tomasz Napierala under sponsorship
13  * from the FreeBSD Foundation.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  */
37 #include <sys/cdefs.h>
38 __RCSID("$NetBSD: fstyp.c,v 1.2 2018/01/09 10:47:57 martin Exp $");
39 
40 #include <sys/disklabel.h>
41 #include <sys/dkio.h>
42 #include <sys/ioctl.h>
43 #include <sys/stat.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <stdbool.h>
47 #include <stddef.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <vis.h>
53 
54 #include "fstyp.h"
55 
56 #define	LABEL_LEN	256
57 
58 typedef int (*fstyp_function)(FILE *, char *, size_t);
59 typedef int (*fsvtyp_function)(const char *, char *, size_t);
60 
61 static struct {
62 	const char	*name;
63 	fstyp_function	function;
64 	bool		unmountable;
65 } fstypes[] = {
66 	{ "cd9660", &fstyp_cd9660, false },
67 	{ "ext2fs", &fstyp_ext2fs, false },
68 	{ "msdosfs", &fstyp_msdosfs, false },
69 	{ "ntfs", &fstyp_ntfs, false },
70 	{ "ufs", &fstyp_ufs, false },
71 #ifdef HAVE_ZFS
72 	{ "zfs", &fstyp_zfs, true },
73 #endif
74 	{ NULL, NULL, NULL }
75 };
76 
77 static struct {
78 	const char	*name;
79 	fsvtyp_function	function;
80 	bool		unmountable;
81 } fsvtypes[] = {
82 	{ NULL, NULL, NULL }
83 };
84 
85 void *
86 read_buf(FILE *fp, off_t off, size_t len)
87 {
88 	int error;
89 	size_t nread;
90 	void *buf;
91 
92 	error = fseeko(fp, off, SEEK_SET);
93 	if (error != 0) {
94 		warn("cannot seek to %jd", (uintmax_t)off);
95 		return NULL;
96 	}
97 
98 	buf = malloc(len);
99 	if (buf == NULL) {
100 		warn("cannot malloc %zd bytes of memory", len);
101 		return NULL;
102 	}
103 
104 	nread = fread(buf, len, 1, fp);
105 	if (nread != 1) {
106 		free(buf);
107 		if (feof(fp) == 0)
108 			warn("fread");
109 		return NULL;
110 	}
111 
112 	return buf;
113 }
114 
115 char *
116 checked_strdup(const char *s)
117 {
118 	char *c;
119 
120 	c = strdup(s);
121 	if (c == NULL)
122 		err(EXIT_FAILURE, "strdup");
123 	return c;
124 }
125 
126 void
127 rtrim(char *label, size_t size)
128 {
129 	for (size_t i = size; i > 0; i--) {
130 		size_t j = i - 1;
131 		if (label[j] == '\0')
132 			continue;
133 		else if (label[j] == ' ')
134 			label[j] = '\0';
135 		else
136 			break;
137 	}
138 }
139 
140 __dead static void
141 usage(void)
142 {
143 
144 	fprintf(stderr, "Usage: %s [-l] [-s] [-u] special\n", getprogname());
145 	exit(EXIT_FAILURE);
146 }
147 
148 static void
149 type_check(const char *path, FILE *fp)
150 {
151 	int error, fd;
152 	struct stat sb;
153 	struct disklabel dl;
154 
155 	fd = fileno(fp);
156 
157 	error = fstat(fd, &sb);
158 	if (error != 0)
159 		err(EXIT_FAILURE, "%s: fstat", path);
160 
161 	if (S_ISREG(sb.st_mode))
162 		return;
163 
164 	error = ioctl(fd, DIOCGDINFO, &dl);
165 	if (error != 0)
166 		errx(EXIT_FAILURE, "%s: not a disk", path);
167 }
168 
169 int
170 main(int argc, char **argv)
171 {
172 	int ch, error, i, nbytes;
173 	bool ignore_type = false, show_label = false, show_unmountable = false;
174 	char label[LABEL_LEN + 1], strvised[LABEL_LEN * 4 + 1];
175 	char *path;
176 	const char *name = NULL;
177 	FILE *fp;
178 	fstyp_function fstyp_f;
179 	fsvtyp_function fsvtyp_f;
180 
181 	while ((ch = getopt(argc, argv, "lsu")) != -1) {
182 		switch (ch) {
183 		case 'l':
184 			show_label = true;
185 			break;
186 		case 's':
187 			ignore_type = true;
188 			break;
189 		case 'u':
190 			show_unmountable = true;
191 			break;
192 		default:
193 			usage();
194 		}
195 	}
196 
197 	argc -= optind;
198 	argv += optind;
199 	if (argc != 1)
200 		usage();
201 
202 	path = argv[0];
203 
204 	fp = fopen(path, "r");
205 	if (fp == NULL)
206 		goto fsvtyp; /* DragonFly */
207 
208 	if (ignore_type == false)
209 		type_check(path, fp);
210 
211 	memset(label, '\0', sizeof(label));
212 
213 	for (i = 0;; i++) {
214 		if (!show_unmountable && fstypes[i].unmountable)
215 			continue;
216 		fstyp_f = fstypes[i].function;
217 		if (fstyp_f == NULL)
218 			break;
219 
220 		error = fstyp_f(fp, label, sizeof(label));
221 		if (error == 0) {
222 			name = fstypes[i].name;
223 			goto done;
224 		}
225 	}
226 fsvtyp:
227 	for (i = 0;; i++) {
228 		if (!show_unmountable && fsvtypes[i].unmountable)
229 			continue;
230 		fsvtyp_f = fsvtypes[i].function;
231 		if (fsvtyp_f == NULL)
232 			break;
233 
234 		error = fsvtyp_f(path, label, sizeof(label));
235 		if (error == 0) {
236 			name = fsvtypes[i].name;
237 			goto done;
238 		}
239 	}
240 
241 	err(EXIT_FAILURE, "%s: filesystem not recognized", path);
242 	/*NOTREACHED*/
243 done:
244 	if (show_label && label[0] != '\0') {
245 		/*
246 		 * XXX: I'd prefer VIS_HTTPSTYLE, but it unconditionally
247 		 *      encodes spaces.
248 		 */
249 		nbytes = strsnvis(strvised, sizeof(strvised), label,
250 		    VIS_GLOB | VIS_NL, "\"'$");
251 		if (nbytes == -1)
252 			err(EXIT_FAILURE, "strsnvis");
253 
254 		printf("%s %s\n", name, strvised);
255 	} else {
256 		printf("%s\n", name);
257 	}
258 
259 	return EXIT_SUCCESS;
260 }
261