1 /*
2 * Copyright (c) 1997-2006 Erez Zadok
3 * Copyright (c) 1990 Jan-Simon Pendry
4 * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
5 * Copyright (c) 1990 The Regents of the University of California.
6 * All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Jan-Simon Pendry at Imperial College, London.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgment:
21 * This product includes software developed by the University of
22 * California, Berkeley and its contributors.
23 * 4. Neither the name of the University nor the names of its contributors
24 * may be used to endorse or promote products derived from this software
25 * without specific prior written permission.
26 *
27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
37 * SUCH DAMAGE.
38 *
39 *
40 * File: am-utils/amd/amfs_link.c
41 *
42 */
43
44 /*
45 * Symbol-link file system
46 */
47
48 #ifdef HAVE_CONFIG_H
49 # include <config.h>
50 #endif /* HAVE_CONFIG_H */
51 #include <am_defs.h>
52 #include <amd.h>
53
54 /* forward declarations */
55 static int amfs_link_mount(am_node *mp, mntfs *mf);
56 static int amfs_link_umount(am_node *mp, mntfs *mf);
57
58 /*
59 * Ops structures
60 */
61 am_ops amfs_link_ops =
62 {
63 "link",
64 amfs_link_match,
65 0, /* amfs_link_init */
66 amfs_link_mount,
67 amfs_link_umount,
68 amfs_error_lookup_child,
69 amfs_error_mount_child,
70 amfs_error_readdir,
71 0, /* amfs_link_readlink */
72 0, /* amfs_link_mounted */
73 0, /* amfs_link_umounted */
74 amfs_generic_find_srvr,
75 0, /* nfs_fs_flags */
76 0, /* amfs_link_get_wchan */
77 #ifdef HAVE_FS_AUTOFS
78 AUTOFS_LINK_FS_FLAGS,
79 #endif /* HAVE_FS_AUTOFS */
80 };
81
82
83 /*
84 * SFS needs a link.
85 */
86 char *
amfs_link_match(am_opts * fo)87 amfs_link_match(am_opts *fo)
88 {
89
90 if (!fo->opt_fs) {
91 plog(XLOG_USER, "link: no fs specified");
92 return 0;
93 }
94
95 /*
96 * If the link target points to another mount point, then we could
97 * end up with an unpleasant situation, where the link f/s simply
98 * "assumes" the mntfs of that mount point.
99 *
100 * For example, if the link points to /usr, and /usr is a real ufs
101 * filesystem, then the link f/s will use the inherited ufs mntfs,
102 * and the end result will be that it will become unmountable.
103 *
104 * To prevent this, we use a hack: we prepend a dot ('.') to opt_fs if
105 * its original value was an absolute path, so that it will never match
106 * any other mntfs.
107 *
108 * XXX: a less hacky solution should be used...
109 */
110 if (fo->opt_fs[0] == '/') {
111 char *link_hack = str3cat(NULL, ".", fo->opt_fs, "");
112 if (!fo->opt_sublink)
113 fo->opt_sublink = strdup(fo->opt_fs);
114 XFREE(fo->opt_fs);
115 fo->opt_fs = link_hack;
116 }
117
118 return strdup(fo->opt_fs);
119 }
120
121
122 static int
amfs_link_mount(am_node * mp,mntfs * mf)123 amfs_link_mount(am_node *mp, mntfs *mf)
124 {
125 return 0;
126 }
127
128
129 static int
amfs_link_umount(am_node * mp,mntfs * mf)130 amfs_link_umount(am_node *mp, mntfs *mf)
131 {
132 return 0;
133 }
134