lib/libfsid/ext2.c

   1 /*
   2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Ákos Kovács <akoskovacs@gmx.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  */
  34
  35 #include <gnu/vfs/ext2fs/ext2_fs.h>
  36 #include <gnu/vfs/ext2fs/fs.h>
  37
  38 #include "libfsid.h"
  39
  40 static char buffer[sizeof(struct ext2_super_block)*2];
  41
  42 fsid_t
  43 ext2_probe(const char *dev)
  44 {
  45         static struct ext2_super_block *fs;
  46
  47         if (fsid_dev_read(dev, SBOFF, sizeof(buffer), buffer) != 0)
  48                 return FSID_UNKNOWN;
  49
  50         fs = (struct ext2_super_block *)&buffer;
  51
  52         if (fs->s_magic == EXT2_SUPER_MAGIC)
  53                 return FSID_EXT2;
  54
  55         return FSID_UNKNOWN;
  56 }
  57
  58 char *
  59 ext2_volname(const char *dev)
  60 {
  61         static struct ext2_super_block *fs;
  62
  63         if (fsid_dev_read(dev, SBOFF, sizeof(buffer), buffer) != 0)
  64                 return NULL;
  65
  66         fs = (struct ext2_super_block *)&buffer;
  67
  68         if (fs->s_magic != EXT2_SUPER_MAGIC || fs->s_volume_name[0] == '\0')
  69                 return NULL;
  70
  71         fs->s_volume_name[sizeof(fs->s_volume_name) - 1] = '\0';
  72
  73         return fs->s_volume_name;
  74 }