Changeset 9f98578 in mainline for uspace/srv/fs/exfat/exfat_fat.c

Timestamp:

2011-07-14T07:03:17Z (13 years ago)

Author:

Oleg Romanenko <romanenko.oleg@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

e584623

Parents:

af4dec0

Message:

exFAT: fat_get_cluster and fat_set_cluster

File:

• uspace/srv/fs/exfat/exfat_fat.c (modified) (1 diff)

uspace/srv/fs/exfat/exfat_fat.c

@@ -59 +59 @@
 
 
+/** Get cluster from the FAT.
+ *
+ * @param bs            Buffer holding the boot sector for the file system.
+ * @param devmap_handle Device handle for the file system.
+ * @param clst          Cluster which to get.
+ * @param value         Output argument holding the value of the cluster.
+ *
+ * @return              EOK or a negative error code.
+ */
+int
+fat_get_cluster(exfat_bs_t *bs, devmap_handle_t devmap_handle,
+    exfat_cluster_t clst, exfat_cluster_t *value)
+{
+        block_t *b;
+        aoff64_t offset;
+        int rc;
+
+        offset = clst * sizeof(exfat_cluster_t);
+
+        rc = block_get(&b, devmap_handle, FAT_FS(bs) + offset / BPS(bs), BLOCK_FLAGS_NONE);
+        if (rc != EOK)
+                return rc;
+
+        *value = uint32_t_le2host(*(uint32_t *)(b->data + offset % BPS(bs)));
+
+        rc = block_put(b);
+
+        return rc;
+}
+
+/** Set cluster in FAT.
+ *
+ * @param bs            Buffer holding the boot sector for the file system.
+ * @param devmap_handle Device handle for the file system.
+ * @param clst          Cluster which is to be set.
+ * @param value         Value to set the cluster with.
+ *
+ * @return              EOK on success or a negative error code.
+ */
+int
+fat_set_cluster(exfat_bs_t *bs, devmap_handle_t devmap_handle,
+    exfat_cluster_t clst, exfat_cluster_t value)
+{
+        block_t *b;
+        aoff64_t offset;
+        int rc;
+
+        offset = clst * sizeof(exfat_cluster_t);
+
+        rc = block_get(&b, devmap_handle, FAT_FS(bs) + offset / BPS(bs), BLOCK_FLAGS_NONE);
+        if (rc != EOK)
+                return rc;
+
+        *(uint32_t *)(b->data + offset % BPS(bs)) = host2uint32_t_le(value);
+
+        b->dirty = true;        /* need to sync block */
+        rc = block_put(b);
+        return rc;
+}
 
 /** Perform basic sanity checks on the file system.