external/bsd/am-utils/dist/amd/info_union.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1997-2009 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 }