xref: /freebsd/lib/libc/gen/fstab.c (revision 0fddbf874719b9bd50cf66ac26d1140bb3f2be69)
1 /*
2  * Copyright (c) 1980, 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #if defined(LIBC_SCCS) && !defined(lint)
35 #if 0
36 static char sccsid[] = "@(#)fstab.c	8.1 (Berkeley) 6/4/93";
37 #else
38 static char rcsid[] =
39  "$FreeBSD$";
40 #endif
41 #endif /* LIBC_SCCS and not lint */
42 
43 #include "namespace.h"
44 #include <sys/param.h>
45 #include <sys/lock.h>
46 #include <sys/mutex.h>
47 #include <sys/mount.h>
48 #include <sys/stat.h>
49 
50 #include <errno.h>
51 #include <fstab.h>
52 #include <paths.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include "un-namespace.h"
58 
59 static FILE *_fs_fp;
60 static struct fstab _fs_fstab;
61 static int LineNo = 0;
62 
63 static void error __P((int));
64 static void fixfsfile __P((void));
65 static int fstabscan __P((void));
66 
67 static void
68 fixfsfile()
69 {
70 	static char buf[sizeof(_PATH_DEV) + MNAMELEN];
71 	struct stat sb;
72 	struct statfs sf;
73 
74 	if (strcmp(_fs_fstab.fs_file, "/") != 0)
75 		return;
76 	if (statfs("/", &sf) != 0)
77 		return;
78 	if (sf.f_mntfromname[0] == '/')
79 		buf[0] = '\0';
80 	else
81 		strcpy(buf, _PATH_DEV);
82 	strcat(buf, sf.f_mntfromname);
83 	if (stat(buf, &sb) != 0 ||
84 	    (!S_ISBLK(sb.st_mode) && !S_ISCHR(sb.st_mode)))
85 		return;
86 	_fs_fstab.fs_spec = buf;
87 }
88 
89 static int
90 fstabscan()
91 {
92 	char *cp, *p;
93 #define	MAXLINELENGTH	1024
94 	static char line[MAXLINELENGTH];
95 	char subline[MAXLINELENGTH];
96 	int typexx;
97 
98 	for (;;) {
99 
100 		if (!(p = fgets(line, sizeof(line), _fs_fp)))
101 			return(0);
102 /* OLD_STYLE_FSTAB */
103 		++LineNo;
104 		if (*line == '#' || *line == '\n')
105 			continue;
106 		if (!strpbrk(p, " \t")) {
107 			_fs_fstab.fs_spec = strsep(&p, ":\n");
108 			_fs_fstab.fs_file = strsep(&p, ":\n");
109 			fixfsfile();
110 			_fs_fstab.fs_type = strsep(&p, ":\n");
111 			if (_fs_fstab.fs_type) {
112 				if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
113 					continue;
114 				_fs_fstab.fs_mntops = _fs_fstab.fs_type;
115 				_fs_fstab.fs_vfstype =
116 				    strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
117 				    "ufs" : "swap";
118 				if ((cp = strsep(&p, ":\n")) != NULL) {
119 					_fs_fstab.fs_freq = atoi(cp);
120 					if ((cp = strsep(&p, ":\n")) != NULL) {
121 						_fs_fstab.fs_passno = atoi(cp);
122 						return(1);
123 					}
124 				}
125 			}
126 			goto bad;
127 		}
128 /* OLD_STYLE_FSTAB */
129 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
130 			;
131 		_fs_fstab.fs_spec = cp;
132 		if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
133 			continue;
134 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
135 			;
136 		_fs_fstab.fs_file = cp;
137 		fixfsfile();
138 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
139 			;
140 		_fs_fstab.fs_vfstype = cp;
141 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
142 			;
143 		_fs_fstab.fs_mntops = cp;
144 		if (_fs_fstab.fs_mntops == NULL)
145 			goto bad;
146 		_fs_fstab.fs_freq = 0;
147 		_fs_fstab.fs_passno = 0;
148 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
149 			;
150 		if (cp != NULL) {
151 			_fs_fstab.fs_freq = atoi(cp);
152 			while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
153 				;
154 			if (cp != NULL)
155 				_fs_fstab.fs_passno = atoi(cp);
156 		}
157 		strcpy(subline, _fs_fstab.fs_mntops);
158 		p = subline;
159 		for (typexx = 0, cp = strsep(&p, ","); cp;
160 		     cp = strsep(&p, ",")) {
161 			if (strlen(cp) != 2)
162 				continue;
163 			if (!strcmp(cp, FSTAB_RW)) {
164 				_fs_fstab.fs_type = FSTAB_RW;
165 				break;
166 			}
167 			if (!strcmp(cp, FSTAB_RQ)) {
168 				_fs_fstab.fs_type = FSTAB_RQ;
169 				break;
170 			}
171 			if (!strcmp(cp, FSTAB_RO)) {
172 				_fs_fstab.fs_type = FSTAB_RO;
173 				break;
174 			}
175 			if (!strcmp(cp, FSTAB_SW)) {
176 				_fs_fstab.fs_type = FSTAB_SW;
177 				break;
178 			}
179 			if (!strcmp(cp, FSTAB_XX)) {
180 				_fs_fstab.fs_type = FSTAB_XX;
181 				typexx++;
182 				break;
183 			}
184 		}
185 		if (typexx)
186 			continue;
187 		if (cp != NULL)
188 			return(1);
189 
190 bad:		/* no way to distinguish between EOF and syntax error */
191 		error(EFTYPE);
192 	}
193 	/* NOTREACHED */
194 }
195 
196 struct fstab *
197 getfsent()
198 {
199 	if ((!_fs_fp && !setfsent()) || !fstabscan())
200 		return((struct fstab *)NULL);
201 	return(&_fs_fstab);
202 }
203 
204 struct fstab *
205 getfsspec(name)
206 	register const char *name;
207 {
208 	if (setfsent())
209 		while (fstabscan())
210 			if (!strcmp(_fs_fstab.fs_spec, name))
211 				return(&_fs_fstab);
212 	return((struct fstab *)NULL);
213 }
214 
215 struct fstab *
216 getfsfile(name)
217 	register const char *name;
218 {
219 	if (setfsent())
220 		while (fstabscan())
221 			if (!strcmp(_fs_fstab.fs_file, name))
222 				return(&_fs_fstab);
223 	return((struct fstab *)NULL);
224 }
225 
226 int
227 setfsent()
228 {
229 	if (_fs_fp) {
230 		rewind(_fs_fp);
231 		LineNo = 0;
232 		return(1);
233 	}
234 	if ((_fs_fp = fopen(_PATH_FSTAB, "r")) != NULL) {
235 		LineNo = 0;
236 		return(1);
237 	}
238 	error(errno);
239 	return(0);
240 }
241 
242 void
243 endfsent()
244 {
245 	if (_fs_fp) {
246 		(void)fclose(_fs_fp);
247 		_fs_fp = NULL;
248 	}
249 }
250 
251 static void
252 error(err)
253 	int err;
254 {
255 	char *p;
256 	char num[30];
257 
258 	(void)_write(STDERR_FILENO, "fstab: ", 7);
259 	(void)_write(STDERR_FILENO, _PATH_FSTAB, sizeof(_PATH_FSTAB) - 1);
260 	(void)_write(STDERR_FILENO, ":", 1);
261 	sprintf(num, "%d: ", LineNo);
262 	(void)_write(STDERR_FILENO, num, strlen(num));
263 	p = strerror(err);
264 	(void)_write(STDERR_FILENO, p, strlen(p));
265 	(void)_write(STDERR_FILENO, "\n", 1);
266 }
267