cluster.c (03.09.09)
exFAT file system implementation library.
- Copyright (C) 2009, 2010 Andrew Nayenko
+ Free exFAT implementation.
+ Copyright (C) 2010-2015 Andrew Nayenko
- This program is free software: you can redistribute it and/or modify
+ 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
+ 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,
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 <http://www.gnu.org/licenses/>.
+ 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 "exfat.h"
#include <errno.h>
#include <string.h>
+#include <inttypes.h>
/*
* Sector to absolute offset.
return cluster + 1;
fat_offset = s2o(ef, le32_to_cpu(ef->sb->fat_sector_start))
+ cluster * sizeof(cluster_t);
- exfat_read_raw(&next, sizeof(next), fat_offset, ef->fd);
+ if (exfat_pread(ef->dev, &next, sizeof(next), fat_offset) < 0)
+ return EXFAT_CLUSTER_BAD; /* the caller should handle this and print
+ appropriate error message */
return le32_to_cpu(next);
}
{
node->fptr_cluster = exfat_next_cluster(ef, node, node->fptr_cluster);
if (CLUSTER_INVALID(node->fptr_cluster))
- break;
+ break; /* the caller should handle this and print appropriate
+ error message */
}
node->fptr_index = count;
return node->fptr_cluster;
}
-static cluster_t find_bit_and_set(uint8_t* bitmap, cluster_t start,
- cluster_t end)
+static cluster_t find_bit_and_set(bitmap_t* bitmap, size_t start, size_t end)
{
- const cluster_t mid_start = (start + 7) / 8 * 8;
- const cluster_t mid_end = end / 8 * 8;
- cluster_t c;
- cluster_t byte;
+ const size_t start_index = start / sizeof(bitmap_t) / 8;
+ const size_t end_index = DIV_ROUND_UP(end, sizeof(bitmap_t) * 8);
+ size_t i;
+ size_t start_bitindex;
+ size_t end_bitindex;
+ size_t c;
+
+ for (i = start_index; i < end_index; i++)
+ {
+ if (bitmap[i] == ~((bitmap_t) 0))
+ continue;
+ start_bitindex = MAX(i * sizeof(bitmap_t) * 8, start);
+ end_bitindex = MIN((i + 1) * sizeof(bitmap_t) * 8, end);
+ for (c = start_bitindex; c < end_bitindex; c++)
+ if (BMAP_GET(bitmap, c) == 0)
+ {
+ BMAP_SET(bitmap, c);
+ return c + EXFAT_FIRST_DATA_CLUSTER;
+ }
+ }
+ return EXFAT_CLUSTER_END;
+}
- for (c = start; c < mid_start; c++)
- if (BMAP_GET(bitmap, c) == 0)
- {
- BMAP_SET(bitmap, c);
- return c + EXFAT_FIRST_DATA_CLUSTER;
- }
+static int flush_nodes(struct exfat* ef, struct exfat_node* node)
+{
+ struct exfat_node* p;
- for (byte = mid_start / 8; byte < mid_end / 8; byte++)
- if (bitmap[byte] != 0xff)
- {
- cluster_t bit;
-
- for (bit = 0; bit < 8; bit++)
- if (!(bitmap[byte] & (1u << bit)))
- {
- bitmap[byte] |= (1u << bit);
- return byte * 8 + bit + EXFAT_FIRST_DATA_CLUSTER;
- }
- }
+ for (p = node->child; p != NULL; p = p->next)
+ {
+ int rc = flush_nodes(ef, p);
+ if (rc != 0)
+ return rc;
+ }
+ return exfat_flush_node(ef, node);
+}
- for (c = mid_end; c < end; c++)
- if (BMAP_GET(bitmap, c) == 0)
+int exfat_flush(struct exfat* ef)
+{
+ int rc = flush_nodes(ef, ef->root);
+
+ if (ef->cmap.dirty)
+ {
+ if (exfat_pwrite(ef->dev, ef->cmap.chunk,
+ BMAP_SIZE(ef->cmap.chunk_size),
+ exfat_c2o(ef, ef->cmap.start_cluster)) < 0)
{
- BMAP_SET(bitmap, c);
- return c + EXFAT_FIRST_DATA_CLUSTER;
+ exfat_error("failed to write clusters bitmap");
+ return -EIO;
}
+ ef->cmap.dirty = false;
+ }
- return EXFAT_CLUSTER_END;
-}
-
-void exfat_flush_cmap(struct exfat* ef)
-{
- exfat_write_raw(ef->cmap.chunk, (ef->cmap.chunk_size + 7) / 8,
- exfat_c2o(ef, ef->cmap.start_cluster), ef->fd);
- ef->cmap.dirty = 0;
+ return rc;
}
-static void set_next_cluster(const struct exfat* ef, int contiguous,
+static bool set_next_cluster(const struct exfat* ef, bool contiguous,
cluster_t current, cluster_t next)
{
off_t fat_offset;
le32_t next_le32;
if (contiguous)
- return;
+ return true;
fat_offset = s2o(ef, le32_to_cpu(ef->sb->fat_sector_start))
+ current * sizeof(cluster_t);
next_le32 = cpu_to_le32(next);
- exfat_write_raw(&next_le32, sizeof(next_le32), fat_offset, ef->fd);
+ if (exfat_pwrite(ef->dev, &next_le32, sizeof(next_le32), fat_offset) < 0)
+ {
+ exfat_error("failed to write the next cluster %#x after %#x", next,
+ current);
+ return false;
+ }
+ return true;
}
static cluster_t allocate_cluster(struct exfat* ef, cluster_t hint)
return EXFAT_CLUSTER_END;
}
- ef->cmap.dirty = 1;
- /* FIXME update percentage of used space */
+ ef->cmap.dirty = true;
return cluster;
}
static void free_cluster(struct exfat* ef, cluster_t cluster)
{
if (CLUSTER_INVALID(cluster))
- exfat_bug("attempting to free invalid cluster");
- if (cluster < EXFAT_FIRST_DATA_CLUSTER ||
- cluster - EXFAT_FIRST_DATA_CLUSTER >= ef->cmap.size)
- exfat_bug("bad cluster 0x%x (0x%x)", cluster, ef->cmap.size);
+ exfat_bug("freeing invalid cluster 0x%x", cluster);
+ if (cluster - EXFAT_FIRST_DATA_CLUSTER >= ef->cmap.size)
+ exfat_bug("freeing non-existing cluster 0x%x (0x%x)", cluster,
+ ef->cmap.size);
BMAP_CLR(ef->cmap.chunk, cluster - EXFAT_FIRST_DATA_CLUSTER);
- ef->cmap.dirty = 1;
- /* FIXME update percentage of used space */
+ ef->cmap.dirty = true;
}
-static void make_noncontiguous(const struct exfat* ef, cluster_t first,
+static bool make_noncontiguous(const struct exfat* ef, cluster_t first,
cluster_t last)
{
cluster_t c;
for (c = first; c < last; c++)
- set_next_cluster(ef, 0, c, c + 1);
+ if (!set_next_cluster(ef, false, c, c + 1))
+ return false;
+ return true;
}
static int shrink_file(struct exfat* ef, struct exfat_node* node,
previous = exfat_advance_cluster(ef, node, current - 1);
if (CLUSTER_INVALID(previous))
{
- exfat_error("invalid cluster in file");
+ exfat_error("invalid cluster 0x%x while growing", previous);
return -EIO;
}
}
{
/* it's a pity, but we are not able to keep the file contiguous
anymore */
- make_noncontiguous(ef, node->start_cluster, previous);
+ if (!make_noncontiguous(ef, node->start_cluster, previous))
+ return -EIO;
node->flags &= ~EXFAT_ATTRIB_CONTIGUOUS;
node->flags |= EXFAT_ATTRIB_DIRTY;
}
- set_next_cluster(ef, IS_CONTIGUOUS(*node), previous, next);
+ if (!set_next_cluster(ef, IS_CONTIGUOUS(*node), previous, next))
+ return -EIO;
previous = next;
allocated++;
}
- set_next_cluster(ef, IS_CONTIGUOUS(*node), previous, EXFAT_CLUSTER_END);
+ if (!set_next_cluster(ef, IS_CONTIGUOUS(*node), previous,
+ EXFAT_CLUSTER_END))
+ return -EIO;
return 0;
}
current - difference - 1);
if (CLUSTER_INVALID(last))
{
- exfat_error("invalid cluster in file");
+ exfat_error("invalid cluster 0x%x while shrinking", last);
return -EIO;
}
previous = exfat_next_cluster(ef, node, last);
- set_next_cluster(ef, IS_CONTIGUOUS(*node), last, EXFAT_CLUSTER_END);
+ if (!set_next_cluster(ef, IS_CONTIGUOUS(*node), last,
+ EXFAT_CLUSTER_END))
+ return -EIO;
}
else
{
previous = node->start_cluster;
node->start_cluster = EXFAT_CLUSTER_FREE;
+ node->flags |= EXFAT_ATTRIB_DIRTY;
}
node->fptr_index = 0;
node->fptr_cluster = node->start_cluster;
{
if (CLUSTER_INVALID(previous))
{
- exfat_error("invalid cluster in file");
+ exfat_error("invalid cluster 0x%x while freeing after shrink",
+ previous);
return -EIO;
}
next = exfat_next_cluster(ef, node, previous);
- set_next_cluster(ef, IS_CONTIGUOUS(*node), previous,
- EXFAT_CLUSTER_FREE);
+ if (!set_next_cluster(ef, IS_CONTIGUOUS(*node), previous,
+ EXFAT_CLUSTER_FREE))
+ return -EIO;
free_cluster(ef, previous);
previous = next;
}
return 0;
}
-static void erase_raw(struct exfat* ef, size_t size, off_t offset)
+static bool erase_raw(struct exfat* ef, size_t size, off_t offset)
{
- exfat_write_raw(ef->zero_sector, size, offset, ef->fd);
+ if (exfat_pwrite(ef->dev, ef->zero_cluster, size, offset) < 0)
+ {
+ exfat_error("failed to erase %zu bytes at %"PRId64, size, offset);
+ return false;
+ }
+ return true;
}
static int erase_range(struct exfat* ef, struct exfat_node* node,
uint64_t begin, uint64_t end)
{
- uint64_t sector_boundary;
+ uint64_t cluster_boundary;
cluster_t cluster;
if (begin >= end)
return 0;
- sector_boundary = (node->size | (SECTOR_SIZE(*ef->sb) - 1)) + 1;
+ cluster_boundary = (begin | (CLUSTER_SIZE(*ef->sb) - 1)) + 1;
cluster = exfat_advance_cluster(ef, node,
- node->size / CLUSTER_SIZE(*ef->sb));
+ begin / CLUSTER_SIZE(*ef->sb));
if (CLUSTER_INVALID(cluster))
{
- exfat_error("invalid cluster in file");
+ exfat_error("invalid cluster 0x%x while erasing", cluster);
return -EIO;
}
- /* erase from the beginning to the closest sector boundary */
- erase_raw(ef, MIN(sector_boundary, end) - node->size,
- exfat_c2o(ef, cluster) + node->size % CLUSTER_SIZE(*ef->sb));
- /* erase whole sectors */
- while (sector_boundary < end)
+ /* erase from the beginning to the closest cluster boundary */
+ if (!erase_raw(ef, MIN(cluster_boundary, end) - begin,
+ exfat_c2o(ef, cluster) + begin % CLUSTER_SIZE(*ef->sb)))
+ return -EIO;
+ /* erase whole clusters */
+ while (cluster_boundary < end)
{
- if (sector_boundary % CLUSTER_SIZE(*ef->sb) == 0)
- cluster = exfat_next_cluster(ef, node, cluster);
- erase_raw(ef, SECTOR_SIZE(*ef->sb),
- exfat_c2o(ef, cluster) + sector_boundary % CLUSTER_SIZE(*ef->sb));
- sector_boundary += SECTOR_SIZE(*ef->sb);
+ cluster = exfat_next_cluster(ef, node, cluster);
+ /* the cluster cannot be invalid because we have just allocated it */
+ if (CLUSTER_INVALID(cluster))
+ exfat_bug("invalid cluster 0x%x after allocation", cluster);
+ if (!erase_raw(ef, CLUSTER_SIZE(*ef->sb), exfat_c2o(ef, cluster)))
+ return -EIO;
+ cluster_boundary += CLUSTER_SIZE(*ef->sb);
}
return 0;
}
-int exfat_truncate(struct exfat* ef, struct exfat_node* node, uint64_t size)
+int exfat_truncate(struct exfat* ef, struct exfat_node* node, uint64_t size,
+ bool erase)
{
uint32_t c1 = bytes2clusters(ef, node->size);
uint32_t c2 = bytes2clusters(ef, size);
if (rc != 0)
return rc;
- rc = erase_range(ef, node, node->size, size);
- if (rc != 0)
- return rc;
+ if (erase)
+ {
+ rc = erase_range(ef, node, node->size, size);
+ if (rc != 0)
+ return rc;
+ }
exfat_update_mtime(node);
node->size = size;
projects / sven / exfat-utils.git / blobdiff