fstab.c revision 42232 
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)
35static char sccsid[] = "@(#)fstab.c	8.1 (Berkeley) 6/4/93";
36#endif /* LIBC_SCCS and not lint */
37
38#include <sys/param.h>
39#include <sys/mount.h>
40#include <sys/stat.h>
41
42#include <errno.h>
43#include <fstab.h>
44#include <paths.h>
45#include <stdio.h>
46#include <stdlib.h>
47#include <string.h>
48#include <unistd.h>
49
50static FILE *_fs_fp;
51static struct fstab _fs_fstab;
52static int LineNo = 0;
53
54static void error __P((int));
55static void fixfsfile __P((void));
56static int fstabscan __P((void));
57
58static void
59fixfsfile()
60{
61	static char buf[sizeof(_PATH_DEV) + MNAMELEN];
62	struct stat sb;
63	struct statfs sf;
64
65	if (strcmp(_fs_fstab.fs_file, "/") != 0)
66		return;
67	if (statfs("/", &sf) != 0)
68		return;
69	if (sf.f_mntfromname[0] == '/')
70		buf[0] = '\0';
71	else
72		strcpy(buf, _PATH_DEV);
73	strcat(buf, sf.f_mntfromname);
74	if (stat(buf, &sb) != 0 || !S_ISBLK(sb.st_mode))
75		return;
76	_fs_fstab.fs_spec = buf;
77}
78
79static int
80fstabscan()
81{
82	char *cp, *p;
83#define	MAXLINELENGTH	1024
84	static char line[MAXLINELENGTH];
85	char subline[MAXLINELENGTH];
86	int typexx;
87
88	for (;;) {
89
90		if (!(p = fgets(line, sizeof(line), _fs_fp)))
91			return(0);
92/* OLD_STYLE_FSTAB */
93		++LineNo;
94		if (*line == '#' || *line == '\n')
95			continue;
96		if (!strpbrk(p, " \t")) {
97			_fs_fstab.fs_spec = strsep(&p, ":\n");
98			_fs_fstab.fs_file = strsep(&p, ":\n");
99			fixfsfile();
100			_fs_fstab.fs_type = strsep(&p, ":\n");
101			if (_fs_fstab.fs_type) {
102				if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
103					continue;
104				_fs_fstab.fs_mntops = _fs_fstab.fs_type;
105				_fs_fstab.fs_vfstype =
106				    strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
107				    "ufs" : "swap";
108				if ((cp = strsep(&p, ":\n")) != NULL) {
109					_fs_fstab.fs_freq = atoi(cp);
110					if ((cp = strsep(&p, ":\n")) != NULL) {
111						_fs_fstab.fs_passno = atoi(cp);
112						return(1);
113					}
114				}
115			}
116			goto bad;
117		}
118/* OLD_STYLE_FSTAB */
119		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
120			;
121		_fs_fstab.fs_spec = cp;
122		if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
123			continue;
124		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
125			;
126		_fs_fstab.fs_file = cp;
127		fixfsfile();
128		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
129			;
130		_fs_fstab.fs_vfstype = cp;
131		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
132			;
133		_fs_fstab.fs_mntops = cp;
134		if (_fs_fstab.fs_mntops == NULL)
135			goto bad;
136		_fs_fstab.fs_freq = 0;
137		_fs_fstab.fs_passno = 0;
138		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
139			;
140		if (cp != NULL) {
141			_fs_fstab.fs_freq = atoi(cp);
142			while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
143				;
144			if (cp != NULL)
145				_fs_fstab.fs_passno = atoi(cp);
146		}
147		strcpy(subline, _fs_fstab.fs_mntops);
148		p = subline;
149		for (typexx = 0, cp = strsep(&p, ","); cp;
150		     cp = strsep(&p, ",")) {
151			if (strlen(cp) != 2)
152				continue;
153			if (!strcmp(cp, FSTAB_RW)) {
154				_fs_fstab.fs_type = FSTAB_RW;
155				break;
156			}
157			if (!strcmp(cp, FSTAB_RQ)) {
158				_fs_fstab.fs_type = FSTAB_RQ;
159				break;
160			}
161			if (!strcmp(cp, FSTAB_RO)) {
162				_fs_fstab.fs_type = FSTAB_RO;
163				break;
164			}
165			if (!strcmp(cp, FSTAB_SW)) {
166				_fs_fstab.fs_type = FSTAB_SW;
167				break;
168			}
169			if (!strcmp(cp, FSTAB_XX)) {
170				_fs_fstab.fs_type = FSTAB_XX;
171				typexx++;
172				break;
173			}
174		}
175		if (typexx)
176			continue;
177		if (cp != NULL)
178			return(1);
179
180bad:		/* no way to distinguish between EOF and syntax error */
181		error(EFTYPE);
182	}
183	/* NOTREACHED */
184}
185
186struct fstab *
187getfsent()
188{
189	if ((!_fs_fp && !setfsent()) || !fstabscan())
190		return((struct fstab *)NULL);
191	return(&_fs_fstab);
192}
193
194struct fstab *
195getfsspec(name)
196	register const char *name;
197{
198	if (setfsent())
199		while (fstabscan())
200			if (!strcmp(_fs_fstab.fs_spec, name))
201				return(&_fs_fstab);
202	return((struct fstab *)NULL);
203}
204
205struct fstab *
206getfsfile(name)
207	register const char *name;
208{
209	if (setfsent())
210		while (fstabscan())
211			if (!strcmp(_fs_fstab.fs_file, name))
212				return(&_fs_fstab);
213	return((struct fstab *)NULL);
214}
215
216int
217setfsent()
218{
219	if (_fs_fp) {
220		rewind(_fs_fp);
221		LineNo = 0;
222		return(1);
223	}
224	if ((_fs_fp = fopen(_PATH_FSTAB, "r")) != NULL) {
225		LineNo = 0;
226		return(1);
227	}
228	error(errno);
229	return(0);
230}
231
232void
233endfsent()
234{
235	if (_fs_fp) {
236		(void)fclose(_fs_fp);
237		_fs_fp = NULL;
238	}
239}
240
241static void
242error(err)
243	int err;
244{
245	char *p;
246	char num[30];
247
248	(void)write(STDERR_FILENO, "fstab: ", 7);
249	(void)write(STDERR_FILENO, _PATH_FSTAB, sizeof(_PATH_FSTAB) - 1);
250	(void)write(STDERR_FILENO, ":", 1);
251	sprintf(num, "%d: ", LineNo);
252	(void)write(STDERR_FILENO, num, strlen(num));
253	p = strerror(err);
254	(void)write(STDERR_FILENO, p, strlen(p));
255	(void)write(STDERR_FILENO, "\n", 1);
256}
257