/*
cbm.c (09.11.10)
Clusters Bitmap creation code.
Copyright (C) 2009, 2010 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 3 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, see .
*/
#include
#include
#include
#include
#include "mkexfat.h"
#include "uct.h"
#include "rootdir.h"
off_t cbm_alignment(void)
{
return CLUSTER_SIZE(sb);
}
off_t cbm_size(void)
{
return DIV_ROUND_UP(le32_to_cpu(sb.cluster_count), CHAR_BIT);
}
int cbm_write(struct exfat_dev* dev, off_t base)
{
uint32_t allocated_clusters =
DIV_ROUND_UP(cbm_size(), CLUSTER_SIZE(sb)) +
DIV_ROUND_UP(uct_size(), CLUSTER_SIZE(sb)) +
DIV_ROUND_UP(rootdir_size(), CLUSTER_SIZE(sb));
size_t bitmap_size = DIV_ROUND_UP(allocated_clusters, CHAR_BIT);
uint8_t* bitmap = malloc(bitmap_size);
size_t i;
if (bitmap == NULL)
return errno;
for (i = 0; i < bitmap_size * CHAR_BIT; i++)
if (i < allocated_clusters)
BMAP_SET(bitmap, i);
else
BMAP_CLR(bitmap, i);
if (exfat_write(dev, bitmap, bitmap_size) < 0)
return errno;
free(bitmap);
sb.cluster_sector_start = cpu_to_le32(base / SECTOR_SIZE(sb));
bitmap_entry.start_cluster = cpu_to_le32(OFFSET_TO_CLUSTER(base));
bitmap_entry.size = cpu_to_le64(cbm_size());
return 0;
}