xref: /dragonfly/lib/libc/gen/fstab.c (revision 2038fb68)
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  * 4. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)fstab.c	8.1 (Berkeley) 6/4/93
30  * $FreeBSD: src/lib/libc/gen/fstab.c,v 1.15 2007/01/09 00:27:53 imp Exp $
31  * $DragonFly: src/lib/libc/gen/fstab.c,v 1.6 2005/11/13 00:07:42 swildner Exp $
32  */
33 
34 #include "namespace.h"
35 #include <sys/param.h>
36 #include <sys/mount.h>
37 #include <sys/stat.h>
38 
39 #include <errno.h>
40 #include <fstab.h>
41 #include <paths.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <unistd.h>
46 #include "un-namespace.h"
47 
48 static FILE *_fs_fp;
49 static struct fstab _fs_fstab;
50 static int LineNo = 0;
51 static char *path_fstab;
52 static char fstab_path[PATH_MAX];
53 static int fsp_set = 0;
54 
55 static void error(int);
56 static void fixfsfile(void);
57 static int fstabscan(void);
58 
59 void
60 setfstab(const char *file)
61 {
62 
63 	if (file == NULL) {
64 		path_fstab = _PATH_FSTAB;
65 	} else {
66 		strncpy(fstab_path, file, PATH_MAX);
67 		fstab_path[PATH_MAX - 1] = '\0';
68 		path_fstab = fstab_path;
69 	}
70 	fsp_set = 1;
71 }
72 
73 const char *
74 getfstab(void)
75 {
76 
77 	if (fsp_set)
78 		return (path_fstab);
79 	else
80 		return (_PATH_FSTAB);
81 }
82 
83 static void
84 fixfsfile(void)
85 {
86 	static char buf[sizeof(_PATH_DEV) + MNAMELEN];
87 	struct stat sb;
88 	struct statfs sf;
89 
90 	if (strcmp(_fs_fstab.fs_file, "/") != 0)
91 		return;
92 	if (statfs("/", &sf) != 0)
93 		return;
94 	if (sf.f_mntfromname[0] == '/')
95 		buf[0] = '\0';
96 	else
97 		strcpy(buf, _PATH_DEV);
98 	strcat(buf, sf.f_mntfromname);
99 	if (stat(buf, &sb) != 0 ||
100 	    (!S_ISBLK(sb.st_mode) && !S_ISCHR(sb.st_mode)))
101 		return;
102 	_fs_fstab.fs_spec = buf;
103 }
104 
105 static int
106 fstabscan(void)
107 {
108 	char *cp, *p;
109 #define	MAXLINELENGTH	1024
110 	static char line[MAXLINELENGTH];
111 	char subline[MAXLINELENGTH];
112 	int typexx;
113 
114 	for (;;) {
115 
116 		if (!(p = fgets(line, sizeof(line), _fs_fp)))
117 			return(0);
118 /* OLD_STYLE_FSTAB */
119 		++LineNo;
120 		if (*line == '#' || *line == '\n')
121 			continue;
122 		if (!strpbrk(p, " \t")) {
123 			_fs_fstab.fs_spec = strsep(&p, ":\n");
124 			_fs_fstab.fs_file = strsep(&p, ":\n");
125 			fixfsfile();
126 			_fs_fstab.fs_type = strsep(&p, ":\n");
127 			if (_fs_fstab.fs_type) {
128 				if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
129 					continue;
130 				_fs_fstab.fs_mntops = _fs_fstab.fs_type;
131 				_fs_fstab.fs_vfstype =
132 				    strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
133 				    "ufs" : "swap";
134 				if ((cp = strsep(&p, ":\n")) != NULL) {
135 					_fs_fstab.fs_freq = atoi(cp);
136 					if ((cp = strsep(&p, ":\n")) != NULL) {
137 						_fs_fstab.fs_passno = atoi(cp);
138 						return(1);
139 					}
140 				}
141 			}
142 			goto bad;
143 		}
144 /* OLD_STYLE_FSTAB */
145 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
146 			;
147 		_fs_fstab.fs_spec = cp;
148 		if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
149 			continue;
150 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
151 			;
152 		_fs_fstab.fs_file = cp;
153 		fixfsfile();
154 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
155 			;
156 		_fs_fstab.fs_vfstype = cp;
157 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
158 			;
159 		_fs_fstab.fs_mntops = cp;
160 		if (_fs_fstab.fs_mntops == NULL)
161 			goto bad;
162 		_fs_fstab.fs_freq = 0;
163 		_fs_fstab.fs_passno = 0;
164 		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
165 			;
166 		if (cp != NULL) {
167 			_fs_fstab.fs_freq = atoi(cp);
168 			while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
169 				;
170 			if (cp != NULL)
171 				_fs_fstab.fs_passno = atoi(cp);
172 		}
173 		strcpy(subline, _fs_fstab.fs_mntops);
174 		p = subline;
175 		for (typexx = 0, cp = strsep(&p, ","); cp;
176 		     cp = strsep(&p, ",")) {
177 			if (strlen(cp) != 2)
178 				continue;
179 			if (!strcmp(cp, FSTAB_RW)) {
180 				_fs_fstab.fs_type = FSTAB_RW;
181 				break;
182 			}
183 			if (!strcmp(cp, FSTAB_RQ)) {
184 				_fs_fstab.fs_type = FSTAB_RQ;
185 				break;
186 			}
187 			if (!strcmp(cp, FSTAB_RO)) {
188 				_fs_fstab.fs_type = FSTAB_RO;
189 				break;
190 			}
191 			if (!strcmp(cp, FSTAB_SW)) {
192 				_fs_fstab.fs_type = FSTAB_SW;
193 				break;
194 			}
195 			if (!strcmp(cp, FSTAB_XX)) {
196 				_fs_fstab.fs_type = FSTAB_XX;
197 				typexx++;
198 				break;
199 			}
200 		}
201 		if (typexx)
202 			continue;
203 		if (cp != NULL)
204 			return(1);
205 
206 bad:		/* no way to distinguish between EOF and syntax error */
207 		error(EFTYPE);
208 	}
209 	/* NOTREACHED */
210 }
211 
212 struct fstab *
213 getfsent(void)
214 {
215 	if ((!_fs_fp && !setfsent()) || !fstabscan())
216 		return(NULL);
217 	return(&_fs_fstab);
218 }
219 
220 struct fstab *
221 getfsspec(const char *name)
222 {
223 	if (setfsent())
224 		while (fstabscan())
225 			if (!strcmp(_fs_fstab.fs_spec, name))
226 				return(&_fs_fstab);
227 	return(NULL);
228 }
229 
230 struct fstab *
231 getfsfile(const char *name)
232 {
233 	if (setfsent())
234 		while (fstabscan())
235 			if (!strcmp(_fs_fstab.fs_file, name))
236 				return(&_fs_fstab);
237 	return(NULL);
238 }
239 
240 int
241 setfsent(void)
242 {
243 	if (_fs_fp) {
244 		rewind(_fs_fp);
245 		LineNo = 0;
246 		return(1);
247 	}
248 	if (fsp_set == 0) {
249 		if (issetugid())
250 			setfstab(NULL);
251 		else
252 			setfstab(getenv("PATH_FSTAB"));
253 	}
254 	if ((_fs_fp = fopen(path_fstab, "r")) != NULL) {
255 		LineNo = 0;
256 		return(1);
257 	}
258 	error(errno);
259 	return(0);
260 }
261 
262 void
263 endfsent(void)
264 {
265 	if (_fs_fp) {
266 		fclose(_fs_fp);
267 		_fs_fp = NULL;
268 	}
269 
270 	fsp_set = 0;
271 }
272 
273 static void
274 error(int err)
275 {
276 	char *p;
277 	char num[30];
278 
279 	_write(STDERR_FILENO, "fstab: ", 7);
280 	_write(STDERR_FILENO, path_fstab, strlen(path_fstab));
281 	_write(STDERR_FILENO, ":", 1);
282 	sprintf(num, "%d: ", LineNo);
283 	_write(STDERR_FILENO, num, strlen(num));
284 	p = strerror(err);
285 	_write(STDERR_FILENO, p, strlen(p));
286 	_write(STDERR_FILENO, "\n", 1);
287 }
288