1/*
2 * Copyright (c) 1997-2014 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. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 *
36 * File: am-utils/amd/info_union.c
37 *
38 */
39
40/*
41 * Get info from the system namespace
42 *
43 * NOTE: Cannot handle reads back through the automounter.
44 * THIS WILL CAUSE A DEADLOCK!
45 */
46
47#ifdef HAVE_CONFIG_H
48# include <config.h>
49#endif /* HAVE_CONFIG_H */
50#include <am_defs.h>
51#include <amd.h>
52
53#define	UNION_PREFIX	"union:"
54#define	UNION_PREFLEN	6
55
56/* forward declarations */
57int union_init(mnt_map *m, char *map, time_t *tp);
58int union_search(mnt_map *m, char *map, char *key, char **pval, time_t *tp);
59int union_reload(mnt_map *m, char *map, void (*fn) (mnt_map *, char *, char *));
60
61
62/*
63 * No way to probe - check the map name begins with "union:"
64 */
65int
66union_init(mnt_map *m, char *map, time_t *tp)
67{
68  *tp = 0;
69  return NSTREQ(map, UNION_PREFIX, UNION_PREFLEN) ? 0 : ENOENT;
70}
71
72
73int
74union_search(mnt_map *m, char *map, char *key, char **pval, time_t *tp)
75{
76  char *mapd = xstrdup(map + UNION_PREFLEN);
77  char **v = strsplit(mapd, ':', '\"');
78  char **p;
79  size_t l;
80
81  for (p = v; p[1]; p++) ;
82  l = strlen(*p) + 5;
83  *pval = xmalloc(l);
84  xsnprintf(*pval, l, "fs:=%s", *p);
85  XFREE(mapd);
86  XFREE(v);
87  return 0;
88}
89
90
91int
92union_reload(mnt_map *m, char *map, void (*fn) (mnt_map *, char *, char *))
93{
94  static const char fseq[] = "fs:=";
95  char *mapd = xstrdup(map + UNION_PREFLEN);
96  char **v = strsplit(mapd, ':', '\"');
97  char **dir;
98
99  /*
100   * Add fake /defaults entry
101   */
102  (*fn) (m, xstrdup("/defaults"), xstrdup("type:=link;opts:=nounmount;sublink:=${key}"));
103
104  for (dir = v; *dir; dir++) {
105    size_t l;
106    struct dirent *dp;
107
108    DIR *dirp = opendir(*dir);
109    if (!dirp) {
110      plog(XLOG_USER, "Cannot read directory %s: %m", *dir);
111      continue;
112    }
113    l = strlen(*dir) + sizeof(fseq);
114
115    dlog("Reading directory %s...", *dir);
116    while ((dp = readdir(dirp))) {
117      char *val, *dpname = &dp->d_name[0];
118      if (dpname[0] == '.' &&
119	  (dpname[1] == '\0' ||
120	   (dpname[1] == '.' && dpname[2] == '\0')))
121	continue;
122
123      dlog("... gives %s", dp->d_name);
124      val = xmalloc(l);
125      xsnprintf(val, l, "%s%s", fseq, *dir);
126      (*fn) (m, xstrdup(dp->d_name), val);
127    }
128    closedir(dirp);
129  }
130
131  /*
132   * Add wildcard entry
133   */
134  {
135    size_t l = strlen(*(dir-1)) + sizeof(fseq);
136    char *val = xmalloc(l);
137
138    xsnprintf(val, l, "%s%s", fseq, *(dir-1));
139    (*fn) (m, xstrdup("*"), val);
140  }
141  XFREE(mapd);
142  XFREE(v);
143  return 0;
144}
145