usr.sbin/installer/libinstaller/mount.c

   1 /*
   2  * Copyright (c) 2004-09 The DragonFly Project.  All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  *
   8  *   Redistributions of source code must retain the above copyright
   9  *   notice, this list of conditions and the following disclaimer.
  10  *
  11  *   Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in
  13  *   the documentation and/or other materials provided with the
  14  *   distribution.
  15  *
  16  *   Neither the name of the DragonFly Project nor the names of its
  17  *   contributors may be used to endorse or promote products derived
  18  *   from this software without specific prior written permission.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  24  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  25  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  26  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  27  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  29  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  31  * OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 /*
  35  * mount.c
  36  * $Id: mount.c,v 1.4 2005/02/10 03:33:49 cpressey Exp $
  37  */
  38
  39 #include <sys/stat.h>
  40 #include <sys/param.h>
  41 #include <sys/ucred.h>
  42 #include <sys/mount.h>
  43
  44 #include <stdarg.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <unistd.h>
  49
  50 #include "libaura/fspred.h"
  51
  52 #include "commands.h"
  53 #include "functions.h"
  54
  55 static int
  56 compare(const void *a, const void *b)
  57 {
  58         const struct statfs *sa = a;
  59         const struct statfs *sb = b;
  60
  61         return -strcmp(sa->f_mntonname,
  62             sb->f_mntonname);
  63 }
  64
  65 /*
  66  * Unmount all mountpoints under a given mountpoint in order (e.g. /var/tmp is
  67  * unmounted before /var).
  68  */
  69 void
  70 unmount_all_under(struct i_fn_args *a, struct commands *cmds, const char *fmt, ...)
  71 {
  72         struct statfs *mt_array;
  73         int count, i;
  74         char *mtpt;
  75         va_list args;
  76
  77         va_start(args, fmt);
  78         vasprintf(&mtpt, fmt, args);
  79         va_end(args);
  80
  81         count = getmntinfo(&mt_array, MNT_WAIT);
  82
  83         /* Order mount points in reverse lexicographically order. */
  84         qsort((void*)mt_array, count, sizeof(struct statfs), compare);
  85
  86         for (i = 0; i < count; i++) {
  87                 if (strncmp(mtpt, mt_array[i].f_mntonname, strlen(mtpt)) != 0)
  88                         continue;
  89                 if (strlen(mtpt) > strlen(mt_array[i].f_mntonname))
  90                         continue;
  91
  92                 command_add(cmds, "%s%s %s",
  93                     a->os_root, cmd_name(a, "UMOUNT"), mt_array[i].f_mntonname);
  94         }
  95
  96         free(mtpt);
  97 }