Imported Upstream version 0.9.8
[sven/exfat-utils.git] / mkfs / cbm.c
1 /*
2         cbm.c (09.11.10)
3         Clusters Bitmap creation code.
4
5         Copyright (C) 2011, 2012  Andrew Nayenko
6
7         This program is free software: you can redistribute it and/or modify
8         it under the terms of the GNU General Public License as published by
9         the Free Software Foundation, either version 3 of the License, or
10         (at your option) any later version.
11
12         This program is distributed in the hope that it will be useful,
13         but WITHOUT ANY WARRANTY; without even the implied warranty of
14         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15         GNU General Public License for more details.
16
17         You should have received a copy of the GNU General Public License
18         along with this program.  If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include <limits.h>
22 #include "cbm.h"
23 #include "fat.h"
24 #include "uct.h"
25 #include "rootdir.h"
26
27 static off_t cbm_alignment(void)
28 {
29         return get_cluster_size();
30 }
31
32 static off_t cbm_size(void)
33 {
34         return DIV_ROUND_UP(
35                         (get_volume_size() - get_position(&cbm)) / get_cluster_size(),
36                         CHAR_BIT);
37 }
38
39 static int cbm_write(struct exfat_dev* dev)
40 {
41         uint32_t allocated_clusters =
42                         DIV_ROUND_UP(cbm.get_size(), get_cluster_size()) +
43                         DIV_ROUND_UP(uct.get_size(), get_cluster_size()) +
44                         DIV_ROUND_UP(rootdir.get_size(), get_cluster_size());
45         size_t bitmap_size = DIV_ROUND_UP(allocated_clusters, CHAR_BIT);
46         uint8_t* bitmap = malloc(bitmap_size);
47         size_t i;
48
49         if (bitmap == NULL)
50         {
51                 exfat_error("failed to allocate bitmap of %zu bytes", bitmap_size);
52                 return 1;
53         }
54
55         for (i = 0; i < bitmap_size * CHAR_BIT; i++)
56                 if (i < allocated_clusters)
57                         BMAP_SET(bitmap, i);
58                 else
59                         BMAP_CLR(bitmap, i);
60         if (exfat_write(dev, bitmap, bitmap_size) < 0)
61         {
62                 exfat_error("failed to write bitmap of %zu bytes", bitmap_size);
63                 return 1;
64         }
65         free(bitmap);
66         return 0;
67 }
68
69 const struct fs_object cbm =
70 {
71         .get_alignment = cbm_alignment,
72         .get_size = cbm_size,
73         .write = cbm_write,
74 };