xref: /openbsd/lib/libc/gen/fstab.c (revision d485f761)
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 static char rcsid[] = "$OpenBSD: fstab.c,v 1.9 2001/06/27 00:58:54 lebel Exp $";
36 #endif /* LIBC_SCCS and not lint */
37 
38 #include <sys/types.h>
39 #include <sys/uio.h>
40 #include <sys/stat.h>
41 
42 #include <errno.h>
43 #include <limits.h>
44 #include <fstab.h>
45 #include <stdio.h>
46 #include <stdlib.h>
47 #include <string.h>
48 #include <unistd.h>
49 
50 static FILE *_fs_fp;
51 static struct fstab _fs_fstab;
52 
53 static void error __P((int));
54 static int fstabscan __P((void));
55 
56 static int
57 fstabscan()
58 {
59 	register char *cp;
60 #define	MAXLINELENGTH	1024
61 	static char line[MAXLINELENGTH];
62 	char subline[MAXLINELENGTH];
63 	char *endp;
64 	int typexx;
65 	long l;
66 
67 	for (;;) {
68 		if (!(cp = fgets(line, sizeof(line), _fs_fp)))
69 			return(0);
70 /* OLD_STYLE_FSTAB */
71 		if (!strpbrk(cp, " \t")) {
72 			_fs_fstab.fs_spec = strtok(cp, ":\n");
73 			if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
74 				continue;
75 			_fs_fstab.fs_file = strtok((char *)NULL, ":\n");
76 			_fs_fstab.fs_type = strtok((char *)NULL, ":\n");
77 			if (_fs_fstab.fs_type) {
78 				if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
79 					continue;
80 				_fs_fstab.fs_mntops = _fs_fstab.fs_type;
81 				_fs_fstab.fs_vfstype =
82 				    strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
83 				    "ufs" : "swap";
84 				if ((cp = strtok((char *)NULL, ":\n"))) {
85 					l = strtol(cp, &endp, 10);
86 					if (endp == cp || *endp != '\0' ||
87 					    l < 0 || l >= INT_MAX)
88 						goto bad;
89 					_fs_fstab.fs_freq = l;
90 					if ((cp = strtok((char *)NULL, ":\n"))) {
91 						l = strtol(cp, &endp, 10);
92 						if (endp == cp || *endp != '\0'
93 						    || l < 0 || l >= INT_MAX)
94 							goto bad;
95 						_fs_fstab.fs_passno = l;
96 						return(1);
97 					}
98 				}
99 			}
100 			goto bad;
101 		}
102 /* OLD_STYLE_FSTAB */
103 		_fs_fstab.fs_spec = strtok(cp, " \t\n");
104 		if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
105 			continue;
106 		_fs_fstab.fs_file = strtok((char *)NULL, " \t\n");
107 		_fs_fstab.fs_vfstype = strtok((char *)NULL, " \t\n");
108 		_fs_fstab.fs_mntops = strtok((char *)NULL, " \t\n");
109 		if (_fs_fstab.fs_mntops == NULL)
110 			goto bad;
111 		_fs_fstab.fs_freq = 0;
112 		_fs_fstab.fs_passno = 0;
113 		if ((cp = strtok((char *)NULL, " \t\n")) != NULL) {
114 			l = strtol(cp, &endp, 10);
115 			if (endp == cp || *endp != '\0' || l < 0 ||
116 			    l >= INT_MAX)
117 				goto bad;
118 			_fs_fstab.fs_freq = l;
119 			if ((cp = strtok((char *)NULL, " \t\n")) != NULL) {
120 				l = strtol(cp, &endp, 10);
121 				if (endp == cp || *endp != '\0' || l < 0 ||
122 				    l >= INT_MAX)
123 					goto bad;
124 				_fs_fstab.fs_passno = l;
125 			}
126 		}
127 		strlcpy(subline, _fs_fstab.fs_mntops, sizeof subline);
128 		for (typexx = 0, cp = strtok(subline, ","); cp;
129 		     cp = strtok((char *)NULL, ",")) {
130 			if (strlen(cp) != 2)
131 				continue;
132 			if (!strcmp(cp, FSTAB_RW)) {
133 				_fs_fstab.fs_type = FSTAB_RW;
134 				break;
135 			}
136 			if (!strcmp(cp, FSTAB_RQ)) {
137 				_fs_fstab.fs_type = FSTAB_RQ;
138 				break;
139 			}
140 			if (!strcmp(cp, FSTAB_RO)) {
141 				_fs_fstab.fs_type = FSTAB_RO;
142 				break;
143 			}
144 			if (!strcmp(cp, FSTAB_SW)) {
145 				_fs_fstab.fs_type = FSTAB_SW;
146 				break;
147 			}
148 			if (!strcmp(cp, FSTAB_XX)) {
149 				_fs_fstab.fs_type = FSTAB_XX;
150 				typexx++;
151 				break;
152 			}
153 		}
154 		if (typexx)
155 			continue;
156 		if (cp != NULL)
157 			return(1);
158 
159 bad:		/* no way to distinguish between EOF and syntax error */
160 		error(EFTYPE);
161 	}
162 	/* NOTREACHED */
163 }
164 
165 struct fstab *
166 getfsent()
167 {
168 	if ((!_fs_fp && !setfsent()) || !fstabscan())
169 		return(NULL);
170 	return(&_fs_fstab);
171 }
172 
173 struct fstab *
174 getfsspec(name)
175 	register const char *name;
176 {
177 	if (setfsent())
178 		while (fstabscan())
179 			if (!strcmp(_fs_fstab.fs_spec, name))
180 				return(&_fs_fstab);
181 	return((struct fstab *)NULL);
182 }
183 
184 struct fstab *
185 getfsfile(name)
186 	register const char *name;
187 {
188 	if (setfsent())
189 		while (fstabscan())
190 			if (!strcmp(_fs_fstab.fs_file, name))
191 				return(&_fs_fstab);
192 	return((struct fstab *)NULL);
193 }
194 
195 int
196 setfsent()
197 {
198 	struct stat sbuf;
199 
200 	if (_fs_fp) {
201 		rewind(_fs_fp);
202 		return(1);
203 	}
204 
205 	if (stat(_PATH_FSTAB, &sbuf) != 0)
206 		goto fail;
207 	if ((sbuf.st_size == 0) || ((sbuf.st_mode & S_IFMT) != S_IFREG)) {
208 		errno = EFTYPE;
209 		goto fail;
210 	}
211 
212 	if ((_fs_fp = fopen(_PATH_FSTAB, "r")))
213 		return(1);
214 
215 fail:
216 	error(errno);
217 	return(0);
218 }
219 
220 void
221 endfsent()
222 {
223 	if (_fs_fp) {
224 		(void)fclose(_fs_fp);
225 		_fs_fp = NULL;
226 	}
227 }
228 
229 static void
230 error(err)
231 	int err;
232 {
233 	struct iovec iov[5];
234 
235 	iov[0].iov_base = "fstab: ";
236 	iov[0].iov_len = 7;
237 	iov[1].iov_base = _PATH_FSTAB;
238 	iov[1].iov_len = sizeof(_PATH_FSTAB) - 1;
239 	iov[2].iov_base =  ": ";
240 	iov[2].iov_len = 2;
241 	iov[3].iov_base = strerror(err);
242 	iov[3].iov_len = strlen(iov[3].iov_base);
243 	iov[4].iov_base = "\n";
244 	iov[4].iov_len = 1;
245 	(void)writev(STDERR_FILENO, iov, 5);
246 }
247