xref: /netbsd-src/external/bsd/am-utils/dist/amd/amfs_auto.c (revision 8bae5d409deb915cf7c8f0539fae22ff2cb8a313)
1 /*	$NetBSD: amfs_auto.c,v 1.1.1.3 2015/01/17 16:34:15 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997-2014 Erez Zadok
5  * Copyright (c) 1990 Jan-Simon Pendry
6  * Copyright (c) 1990 Imperial College of Science, Technology & Medicine
7  * Copyright (c) 1990 The Regents of the University of California.
8  * All rights reserved.
9  *
10  * This code is derived from software contributed to Berkeley by
11  * Jan-Simon Pendry at Imperial College, London.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *
38  * File: am-utils/amd/amfs_auto.c
39  *
40  */
41 
42 /*
43  * Automount file system
44  */
45 
46 #ifdef HAVE_CONFIG_H
47 # include <config.h>
48 #endif /* HAVE_CONFIG_H */
49 #include <am_defs.h>
50 #include <amd.h>
51 
52 /****************************************************************************
53  *** MACROS                                                               ***
54  ****************************************************************************/
55 
56 
57 /****************************************************************************
58  *** STRUCTURES                                                           ***
59  ****************************************************************************/
60 
61 
62 /****************************************************************************
63  *** FORWARD DEFINITIONS                                                  ***
64  ****************************************************************************/
65 static int amfs_auto_mount(am_node *mp, mntfs *mf);
66 
67 
68 /****************************************************************************
69  *** OPS STRUCTURES                                                       ***
70  ****************************************************************************/
71 am_ops amfs_auto_ops =
72 {
73   "auto",
74   amfs_generic_match,
75   0,				/* amfs_auto_init */
76   amfs_auto_mount,
77   amfs_generic_umount,
78   amfs_generic_lookup_child,
79   amfs_generic_mount_child,
80   amfs_generic_readdir,
81   0,				/* amfs_auto_readlink */
82   amfs_generic_mounted,
83   0,				/* amfs_auto_umounted */
84   amfs_generic_find_srvr,
85   0,				/* amfs_auto_get_wchan */
86   FS_AMQINFO | FS_DIRECTORY,
87 #ifdef HAVE_FS_AUTOFS
88   AUTOFS_AUTO_FS_FLAGS,
89 #endif /* HAVE_FS_AUTOFS */
90 };
91 
92 
93 /****************************************************************************
94  *** FUNCTIONS                                                             ***
95  ****************************************************************************/
96 /*
97  * Mount a sub-mount
98  */
99 static int
amfs_auto_mount(am_node * mp,mntfs * mf)100 amfs_auto_mount(am_node *mp, mntfs *mf)
101 {
102   if (mp->am_parent == NULL)
103     return EINVAL;
104   /*
105    * Pseudo-directories are used to provide some structure
106    * to the automounted directories instead
107    * of putting them all in the top-level automount directory.
108    *
109    * Here, just increment the parent's link count.
110    */
111   mp->am_parent->am_fattr.na_nlink++;
112 
113   /*
114    * Info field of . means use parent's info field.
115    * Historical - not documented.
116    */
117   if (mf->mf_info[0] == '.' && mf->mf_info[1] == '\0')
118     mf->mf_info = strealloc(mf->mf_info, mp->am_parent->am_al->al_mnt->mf_info);
119 
120   /*
121    * Compute prefix:
122    *
123    * If there is an option prefix then use that else
124    * If the parent had a prefix then use that with name
125    *      of this node appended else
126    * Use the name of this node.
127    *
128    * That means if you want no prefix you must say so
129    * in the map.
130    */
131   if (mf->mf_fo->opt_pref) {
132     /* allow pref:=null to set a real null prefix */
133     if (STREQ(mf->mf_fo->opt_pref, "null")) {
134       mp->am_pref = xstrdup("");
135     } else {
136       /*
137        * the prefix specified as an option
138        */
139       mp->am_pref = xstrdup(mf->mf_fo->opt_pref);
140     }
141   } else {
142     /*
143      * else the parent's prefix
144      * followed by the name
145      * followed by /
146      */
147     char *ppref = mp->am_parent->am_pref;
148     if (ppref == 0)
149       ppref = "";
150     mp->am_pref = str3cat((char *) NULL, ppref, mp->am_name, "/");
151   }
152 
153 #ifdef HAVE_FS_AUTOFS
154   if (mf->mf_flags & MFF_IS_AUTOFS) {
155     char opts[SIZEOF_OPTS];
156     int error;
157 
158     autofs_get_opts(opts, sizeof(opts), mp->am_autofs_fh);
159 
160     /* now do the mount */
161     error = amfs_mount(mp, mf, opts);
162     if (error) {
163       errno = error;
164       plog(XLOG_FATAL, "amfs_auto_mount: amfs_mount failed: %m");
165       return error;
166     }
167   }
168 #endif /* HAVE_FS_AUTOFS */
169 
170   /*
171    * Attach a map cache
172    */
173   amfs_mkcacheref(mf);
174 
175   return 0;
176 }
177