xref: /netbsd-src/external/bsd/am-utils/dist/amd/info_union.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /*	$NetBSD: info_union.c,v 1.1.1.1 2008/09/19 20:07:16 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997-2007 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. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgment:
23  *      This product includes software developed by the University of
24  *      California, Berkeley and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *
42  * File: am-utils/amd/info_union.c
43  *
44  */
45 
46 /*
47  * Get info from the system namespace
48  *
49  * NOTE: Cannot handle reads back through the automounter.
50  * THIS WILL CAUSE A DEADLOCK!
51  */
52 
53 #ifdef HAVE_CONFIG_H
54 # include <config.h>
55 #endif /* HAVE_CONFIG_H */
56 #include <am_defs.h>
57 #include <amd.h>
58 
59 #define	UNION_PREFIX	"union:"
60 #define	UNION_PREFLEN	6
61 
62 /* forward declarations */
63 int union_init(mnt_map *m, char *map, time_t *tp);
64 int union_search(mnt_map *m, char *map, char *key, char **pval, time_t *tp);
65 int union_reload(mnt_map *m, char *map, void (*fn) (mnt_map *, char *, char *));
66 
67 
68 /*
69  * No way to probe - check the map name begins with "union:"
70  */
71 int
72 union_init(mnt_map *m, char *map, time_t *tp)
73 {
74   *tp = 0;
75   return NSTREQ(map, UNION_PREFIX, UNION_PREFLEN) ? 0 : ENOENT;
76 }
77 
78 
79 int
80 union_search(mnt_map *m, char *map, char *key, char **pval, time_t *tp)
81 {
82   char *mapd = strdup(map + UNION_PREFLEN);
83   char **v = strsplit(mapd, ':', '\"');
84   char **p;
85   size_t l;
86 
87   for (p = v; p[1]; p++) ;
88   l = strlen(*p) + 5;
89   *pval = xmalloc(l);
90   xsnprintf(*pval, l, "fs:=%s", *p);
91   XFREE(mapd);
92   XFREE(v);
93   return 0;
94 }
95 
96 
97 int
98 union_reload(mnt_map *m, char *map, void (*fn) (mnt_map *, char *, char *))
99 {
100   char *mapd = strdup(map + UNION_PREFLEN);
101   char **v = strsplit(mapd, ':', '\"');
102   char **dir;
103 
104   /*
105    * Add fake /defaults entry
106    */
107   (*fn) (m, strdup("/defaults"), strdup("type:=link;opts:=nounmount;sublink:=${key}"));
108 
109   for (dir = v; *dir; dir++) {
110     size_t l;
111     struct dirent *dp;
112 
113     DIR *dirp = opendir(*dir);
114     if (!dirp) {
115       plog(XLOG_USER, "Cannot read directory %s: %m", *dir);
116       continue;
117     }
118     l = strlen(*dir) + 5;
119 
120     dlog("Reading directory %s...", *dir);
121     while ((dp = readdir(dirp))) {
122       char *val, *dpname = &dp->d_name[0];
123       if (dpname[0] == '.' &&
124 	  (dpname[1] == '\0' ||
125 	   (dpname[1] == '.' && dpname[2] == '\0')))
126 	continue;
127 
128       dlog("... gives %s", dp->d_name);
129       val = xmalloc(l);
130       xsnprintf(val, l + 5, "fs:=%s", *dir);
131       (*fn) (m, strdup(dp->d_name), val);
132     }
133     closedir(dirp);
134   }
135 
136   /*
137    * Add wildcard entry
138    */
139   {
140     size_t l = strlen(*(dir-1)) + 5;
141     char *val = xmalloc(l);
142 
143     xsnprintf(val, l, "fs:=%s", *(dir-1));
144     (*fn) (m, strdup("*"), val);
145   }
146   XFREE(mapd);
147   XFREE(v);
148   return 0;
149 }
150