fstab.c revision 113219 
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#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: head/lib/libc/gen/fstab.c 113219 2003-04-07 12:55:00Z mdodd $");
39
40#include "namespace.h"
41#include <sys/param.h>
42#include <sys/mount.h>
43#include <sys/stat.h>
44
45#include <errno.h>
46#include <fstab.h>
47#include <paths.h>
48#include <stdio.h>
49#include <stdlib.h>
50#include <string.h>
51#include <unistd.h>
52#include "un-namespace.h"
53
54static FILE *_fs_fp;
55static struct fstab _fs_fstab;
56static int LineNo = 0;
57static char *path_fstab;
58static char fstab_path[PATH_MAX];
59static int fsp_set = 0;
60
61static void error(int);
62static void fixfsfile(void);
63static int fstabscan(void);
64
65void
66setfstab(const char *file)
67{
68
69	if (file == NULL) {
70		path_fstab = _PATH_FSTAB;
71	} else {
72		strncpy(fstab_path, file, PATH_MAX);
73		fstab_path[PATH_MAX - 1] = '\0';
74		path_fstab = fstab_path;
75	}
76	fsp_set = 1;
77
78	return;
79}
80
81const char *
82getfstab (void)
83{
84
85	if (fsp_set)
86		return (path_fstab);
87	else
88		return (_PATH_FSTAB);
89}
90
91static void
92fixfsfile()
93{
94	static char buf[sizeof(_PATH_DEV) + MNAMELEN];
95	struct stat sb;
96	struct statfs sf;
97
98	if (strcmp(_fs_fstab.fs_file, "/") != 0)
99		return;
100	if (statfs("/", &sf) != 0)
101		return;
102	if (sf.f_mntfromname[0] == '/')
103		buf[0] = '\0';
104	else
105		strcpy(buf, _PATH_DEV);
106	strcat(buf, sf.f_mntfromname);
107	if (stat(buf, &sb) != 0 ||
108	    (!S_ISBLK(sb.st_mode) && !S_ISCHR(sb.st_mode)))
109		return;
110	_fs_fstab.fs_spec = buf;
111}
112
113static int
114fstabscan()
115{
116	char *cp, *p;
117#define	MAXLINELENGTH	1024
118	static char line[MAXLINELENGTH];
119	char subline[MAXLINELENGTH];
120	int typexx;
121
122	for (;;) {
123
124		if (!(p = fgets(line, sizeof(line), _fs_fp)))
125			return(0);
126/* OLD_STYLE_FSTAB */
127		++LineNo;
128		if (*line == '#' || *line == '\n')
129			continue;
130		if (!strpbrk(p, " \t")) {
131			_fs_fstab.fs_spec = strsep(&p, ":\n");
132			_fs_fstab.fs_file = strsep(&p, ":\n");
133			fixfsfile();
134			_fs_fstab.fs_type = strsep(&p, ":\n");
135			if (_fs_fstab.fs_type) {
136				if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
137					continue;
138				_fs_fstab.fs_mntops = _fs_fstab.fs_type;
139				_fs_fstab.fs_vfstype =
140				    strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
141				    "ufs" : "swap";
142				if ((cp = strsep(&p, ":\n")) != NULL) {
143					_fs_fstab.fs_freq = atoi(cp);
144					if ((cp = strsep(&p, ":\n")) != NULL) {
145						_fs_fstab.fs_passno = atoi(cp);
146						return(1);
147					}
148				}
149			}
150			goto bad;
151		}
152/* OLD_STYLE_FSTAB */
153		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
154			;
155		_fs_fstab.fs_spec = cp;
156		if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
157			continue;
158		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
159			;
160		_fs_fstab.fs_file = cp;
161		fixfsfile();
162		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
163			;
164		_fs_fstab.fs_vfstype = cp;
165		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
166			;
167		_fs_fstab.fs_mntops = cp;
168		if (_fs_fstab.fs_mntops == NULL)
169			goto bad;
170		_fs_fstab.fs_freq = 0;
171		_fs_fstab.fs_passno = 0;
172		while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
173			;
174		if (cp != NULL) {
175			_fs_fstab.fs_freq = atoi(cp);
176			while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
177				;
178			if (cp != NULL)
179				_fs_fstab.fs_passno = atoi(cp);
180		}
181		strcpy(subline, _fs_fstab.fs_mntops);
182		p = subline;
183		for (typexx = 0, cp = strsep(&p, ","); cp;
184		     cp = strsep(&p, ",")) {
185			if (strlen(cp) != 2)
186				continue;
187			if (!strcmp(cp, FSTAB_RW)) {
188				_fs_fstab.fs_type = FSTAB_RW;
189				break;
190			}
191			if (!strcmp(cp, FSTAB_RQ)) {
192				_fs_fstab.fs_type = FSTAB_RQ;
193				break;
194			}
195			if (!strcmp(cp, FSTAB_RO)) {
196				_fs_fstab.fs_type = FSTAB_RO;
197				break;
198			}
199			if (!strcmp(cp, FSTAB_SW)) {
200				_fs_fstab.fs_type = FSTAB_SW;
201				break;
202			}
203			if (!strcmp(cp, FSTAB_XX)) {
204				_fs_fstab.fs_type = FSTAB_XX;
205				typexx++;
206				break;
207			}
208		}
209		if (typexx)
210			continue;
211		if (cp != NULL)
212			return(1);
213
214bad:		/* no way to distinguish between EOF and syntax error */
215		error(EFTYPE);
216	}
217	/* NOTREACHED */
218}
219
220struct fstab *
221getfsent()
222{
223	if ((!_fs_fp && !setfsent()) || !fstabscan())
224		return((struct fstab *)NULL);
225	return(&_fs_fstab);
226}
227
228struct fstab *
229getfsspec(name)
230	const char *name;
231{
232	if (setfsent())
233		while (fstabscan())
234			if (!strcmp(_fs_fstab.fs_spec, name))
235				return(&_fs_fstab);
236	return((struct fstab *)NULL);
237}
238
239struct fstab *
240getfsfile(name)
241	const char *name;
242{
243	if (setfsent())
244		while (fstabscan())
245			if (!strcmp(_fs_fstab.fs_file, name))
246				return(&_fs_fstab);
247	return((struct fstab *)NULL);
248}
249
250int
251setfsent()
252{
253	if (_fs_fp) {
254		rewind(_fs_fp);
255		LineNo = 0;
256		return(1);
257	}
258	if (fsp_set == 0) {
259		if (issetugid())
260			setfstab(NULL);
261		else
262			setfstab(getenv("PATH_FSTAB"));
263	}
264	if ((_fs_fp = fopen(path_fstab, "r")) != NULL) {
265		LineNo = 0;
266		return(1);
267	}
268	error(errno);
269	return(0);
270}
271
272void
273endfsent()
274{
275	if (_fs_fp) {
276		(void)fclose(_fs_fp);
277		_fs_fp = NULL;
278	}
279
280	fsp_set = 0;
281}
282
283static void
284error(err)
285	int err;
286{
287	char *p;
288	char num[30];
289
290	(void)_write(STDERR_FILENO, "fstab: ", 7);
291	(void)_write(STDERR_FILENO, path_fstab, strlen(path_fstab));
292	(void)_write(STDERR_FILENO, ":", 1);
293	sprintf(num, "%d: ", LineNo);
294	(void)_write(STDERR_FILENO, num, strlen(num));
295	p = strerror(err);
296	(void)_write(STDERR_FILENO, p, strlen(p));
297	(void)_write(STDERR_FILENO, "\n", 1);
298}
299