xref: /freebsd/sbin/mount/getmntopts.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*-
2  * Copyright (c) 1994
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. 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 
30 #if 0
31 #ifndef lint
32 static char sccsid[] = "@(#)getmntopts.c	8.3 (Berkeley) 3/29/95";
33 #endif /* not lint */
34 #endif
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/mount.h>
40 #include <sys/stat.h>
41 #include <sys/uio.h>
42 
43 #include <err.h>
44 #include <errno.h>
45 #include <stdarg.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 
50 #include "mntopts.h"
51 
52 int getmnt_silent = 0;
53 
54 void
55 getmntopts(const char *options, const struct mntopt *m0, int *flagp,
56 	int *altflagp)
57 {
58 	const struct mntopt *m;
59 	int negative, len;
60 	char *opt, *optbuf, *p;
61 	int *thisflagp;
62 
63 	/* Copy option string, since it is about to be torn asunder... */
64 	if ((optbuf = strdup(options)) == NULL)
65 		err(1, NULL);
66 
67 	for (opt = optbuf; (opt = strtok(opt, ",")) != NULL; opt = NULL) {
68 		/* Check for "no" prefix. */
69 		if (opt[0] == 'n' && opt[1] == 'o') {
70 			negative = 1;
71 			opt += 2;
72 		} else
73 			negative = 0;
74 
75 		/*
76 		 * for options with assignments in them (ie. quotas)
77 		 * ignore the assignment as it's handled elsewhere
78 		 */
79 		p = strchr(opt, '=');
80 		if (p != NULL)
81 			 *++p = '\0';
82 
83 		/* Scan option table. */
84 		for (m = m0; m->m_option != NULL; ++m) {
85 			len = strlen(m->m_option);
86 			if (strncasecmp(opt, m->m_option, len) == 0)
87 				if (opt[len] == '\0' || opt[len] == '=')
88 					break;
89 		}
90 
91 		/* Save flag, or fail if option is not recognized. */
92 		if (m->m_option) {
93 			thisflagp = m->m_altloc ? altflagp : flagp;
94 			if (negative == m->m_inverse)
95 				*thisflagp |= m->m_flag;
96 			else
97 				*thisflagp &= ~m->m_flag;
98 		} else if (!getmnt_silent) {
99 			errx(1, "-o %s: option not supported", opt);
100 		}
101 	}
102 
103 	free(optbuf);
104 }
105 
106 void
107 rmslashes(char *rrpin, char *rrpout)
108 {
109 	char *rrpoutstart;
110 
111 	*rrpout = *rrpin;
112 	for (rrpoutstart = rrpout; *rrpin != '\0'; *rrpout++ = *rrpin++) {
113 
114 		/* skip all double slashes */
115 		while (*rrpin == '/' && *(rrpin + 1) == '/')
116 			 rrpin++;
117 	}
118 
119 	/* remove trailing slash if necessary */
120 	if (rrpout - rrpoutstart > 1 && *(rrpout - 1) == '/')
121 		*(rrpout - 1) = '\0';
122 	else
123 		*rrpout = '\0';
124 }
125 
126 int
127 checkpath(const char *path, char *resolved)
128 {
129 	struct stat sb;
130 
131 	if (realpath(path, resolved) == NULL || stat(resolved, &sb) != 0)
132 		return (1);
133 	if (!S_ISDIR(sb.st_mode)) {
134 		errno = ENOTDIR;
135 		return (1);
136 	}
137 	return (0);
138 }
139 
140 void
141 build_iovec(struct iovec **iov, int *iovlen, const char *name, void *val,
142 	    size_t len)
143 {
144 	int i;
145 
146 	if (*iovlen < 0)
147 		return;
148 	i = *iovlen;
149 	*iov = realloc(*iov, sizeof **iov * (i + 2));
150 	if (*iov == NULL) {
151 		*iovlen = -1;
152 		return;
153 	}
154 	(*iov)[i].iov_base = strdup(name);
155 	(*iov)[i].iov_len = strlen(name) + 1;
156 	i++;
157 	(*iov)[i].iov_base = val;
158 	if (len == (size_t)-1) {
159 		if (val != NULL)
160 			len = strlen(val) + 1;
161 		else
162 			len = 0;
163 	}
164 	(*iov)[i].iov_len = (int)len;
165 	*iovlen = ++i;
166 }
167 
168 /*
169  * This function is needed for compatibility with parameters
170  * which used to use the mount_argf() command for the old mount() syscall.
171  */
172 void
173 build_iovec_argf(struct iovec **iov, int *iovlen, const char *name,
174     const char *fmt, ...)
175 {
176 	va_list ap;
177 	char val[255] = { 0 };
178 
179 	va_start(ap, fmt);
180 	vsnprintf(val, sizeof(val), fmt, ap);
181 	va_end(ap);
182 	build_iovec(iov, iovlen, name, strdup(val), (size_t)-1);
183 }
184 
185 /*
186  * Free the iovec and reset to NULL with zero length.  Useful for calling
187  * nmount in a loop.
188  */
189 void
190 free_iovec(struct iovec **iov, int *iovlen)
191 {
192 	int i;
193 
194 	for (i = 0; i < *iovlen; i++)
195 		free((*iov)[i].iov_base);
196 	free(*iov);
197 }
198