ops_lofs.c revision 82794 
1/*
2 * Copyright (c) 1997-2001 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 *      %W% (Berkeley) %G%
40 *
41 * $Id: ops_lofs.c,v 1.3.2.2 2001/01/12 23:28:57 ro Exp $
42 *
43 */
44
45/*
46 * Loopback file system
47 */
48
49#ifdef HAVE_CONFIG_H
50# include <config.h>
51#endif /* HAVE_CONFIG_H */
52#include <am_defs.h>
53#include <amd.h>
54
55/* forward definitions */
56static char *lofs_match(am_opts *fo);
57static int lofs_fmount(mntfs *mf);
58static int lofs_fumount(mntfs *mf);
59static int mount_lofs(char *dir, char *fs_name, char *opts);
60
61
62/*
63 * Ops structure
64 */
65am_ops lofs_ops =
66{
67  "lofs",
68  lofs_match,
69  0,				/* lofs_init */
70  amfs_auto_fmount,
71  lofs_fmount,
72  amfs_auto_fumount,
73  lofs_fumount,
74  amfs_error_lookuppn,
75  amfs_error_readdir,
76  0,				/* lofs_readlink */
77  0,				/* lofs_mounted */
78  0,				/* lofs_umounted */
79  find_amfs_auto_srvr,
80  FS_MKMNT | FS_NOTIMEOUT | FS_UBACKGROUND | FS_AMQINFO
81};
82
83
84/*
85 * LOFS needs remote filesystem.
86 */
87static char *
88lofs_match(am_opts *fo)
89{
90  if (!fo->opt_rfs) {
91    plog(XLOG_USER, "lofs: no source filesystem specified");
92    return 0;
93  }
94#ifdef DEBUG
95  dlog("LOFS: mounting fs \"%s\" on \"%s\"",
96       fo->opt_rfs, fo->opt_fs);
97#endif /* DEBUG */
98
99  /*
100   * Determine magic cookie to put in mtab
101   */
102  return strdup(fo->opt_rfs);
103}
104
105
106static int
107mount_lofs(char *dir, char *fs_name, char *opts)
108{
109  mntent_t mnt;
110  int flags;
111
112  /*
113   * Figure out the name of the file system type.
114   */
115  MTYPE_TYPE type = MOUNT_TYPE_LOFS;
116
117  /*
118   * Fill in the mount structure
119   */
120  memset((voidp) &mnt, 0, sizeof(mnt));
121  mnt.mnt_dir = dir;
122  mnt.mnt_fsname = fs_name;
123  mnt.mnt_type = MNTTAB_TYPE_LOFS;
124  mnt.mnt_opts = opts;
125
126  flags = compute_mount_flags(&mnt);
127
128  /*
129   * Call generic mount routine
130   */
131  return mount_fs(&mnt, flags, NULL, 0, type, 0, NULL, mnttab_file_name);
132}
133
134
135static int
136lofs_fmount(mntfs *mf)
137{
138  int error;
139
140  error = mount_lofs(mf->mf_mount, mf->mf_info, mf->mf_mopts);
141  if (error) {
142    errno = error;
143    plog(XLOG_ERROR, "mount_lofs: %m");
144    return error;
145  }
146  return 0;
147}
148
149
150static int
151lofs_fumount(mntfs *mf)
152{
153  return UMOUNT_FS(mf->mf_mount, mnttab_file_name);
154}
155