blob: 025057132912c727be12071441fc570ee2413724 [file] [log] [blame]
/*
cbm.c (09.11.10)
Clusters Bitmap creation code.
Free exFAT implementation.
Copyright (C) 2011-2015 Andrew Nayenko
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "cbm.h"
#include "fat.h"
#include "uct.h"
#include "rootdir.h"
#include <limits.h>
#include <string.h>
static off_t cbm_alignment(void)
{
return get_cluster_size();
}
static off_t cbm_size(void)
{
return DIV_ROUND_UP(
(get_volume_size() - get_position(&cbm)) / get_cluster_size(),
CHAR_BIT);
}
static int cbm_write(struct exfat_dev* dev)
{
uint32_t allocated_clusters =
DIV_ROUND_UP(cbm.get_size(), get_cluster_size()) +
DIV_ROUND_UP(uct.get_size(), get_cluster_size()) +
DIV_ROUND_UP(rootdir.get_size(), get_cluster_size());
size_t bitmap_size = ROUND_UP(allocated_clusters, CHAR_BIT);
bitmap_t* bitmap = malloc(BMAP_SIZE(bitmap_size));
size_t i;
if (bitmap == NULL)
{
exfat_error("failed to allocate bitmap of %zu bytes",
BMAP_SIZE(bitmap_size));
return 1;
}
memset(bitmap, 0, BMAP_SIZE(bitmap_size));
for (i = 0; i < bitmap_size; i++)
if (i < allocated_clusters)
BMAP_SET(bitmap, i);
if (exfat_write(dev, bitmap, bitmap_size / CHAR_BIT) < 0)
{
free(bitmap);
exfat_error("failed to write bitmap of %zu bytes",
bitmap_size / CHAR_BIT);
return 1;
}
free(bitmap);
return 0;
}
const struct fs_object cbm =
{
.get_alignment = cbm_alignment,
.get_size = cbm_size,
.write = cbm_write,
};