Relaxed node size check. This fixes pagefile.sys error.

[android-x86/external-exfat.git] / libexfat / node.c

diff --git a/libexfat/node.c b/libexfat/node.c
index c9cee45..6cb0eb0 100644 (file)
--- a/libexfat/node.c
+++ b/libexfat/node.c
@@ -2,11 +2,12 @@
        node.c (09.10.09)
        exFAT file system implementation library.
 
        node.c (09.10.09)
        exFAT file system implementation library.
 

-       Copyright (C) 2009, 2010  Andrew Nayenko
+       Free exFAT implementation.
+       Copyright (C) 2010-2013  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
        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,
        (at your option) any later version.
 
        This program is distributed in the hope that it will be useful,


@@ -14,8 +15,9 @@
        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
        GNU General Public License for more details.
 
        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 "exfat.h"


@@ -44,26 +46,36 @@ void exfat_put_node(struct exfat* ef, struct exfat_node* node)
 {
        if (--node->references < 0)
        {
 {
        if (--node->references < 0)
        {

-               char buffer[EXFAT_NAME_MAX + 1];
-               exfat_get_name(node, buffer, EXFAT_NAME_MAX);
+               char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);

                exfat_bug("reference counter of `%s' is below zero", buffer);
        }
 
        if (node->references == 0)
        {
                exfat_bug("reference counter of `%s' is below zero", buffer);
        }
 
        if (node->references == 0)
        {

-               if (node->flags & EXFAT_ATTRIB_DIRTY)
-                       exfat_flush_node(ef, node);
+               /* FIXME handle I/O error */
+               if (exfat_flush_node(ef, node) != 0)
+                       exfat_bug("node flush failed");

                if (node->flags & EXFAT_ATTRIB_UNLINKED)
                {
                        /* free all clusters and node structure itself */
                if (node->flags & EXFAT_ATTRIB_UNLINKED)
                {
                        /* free all clusters and node structure itself */

-                       exfat_truncate(ef, node, 0);
+                       exfat_truncate(ef, node, 0, true);

                        free(node);
                }
                        free(node);
                }

-               if (ef->cmap.dirty)
-                       exfat_flush_cmap(ef);
+               /* FIXME handle I/O error */
+               if (exfat_flush(ef) != 0)
+                       exfat_bug("flush failed");

        }
 }
 
        }
 }
 

+/**
+ * Cluster + offset from the beginning of the directory to absolute offset.
+ */
+static off_t co2o(struct exfat* ef, cluster_t cluster, off_t offset)
+{
+       return exfat_c2o(ef, cluster) + offset % CLUSTER_SIZE(*ef->sb);
+}
+

 static int opendir(struct exfat* ef, const struct exfat_node* dir,
                struct iterator* it)
 {
 static int opendir(struct exfat* ef, const struct exfat_node* dir,
                struct iterator* it)
 {


@@ -78,8 +90,12 @@ static int opendir(struct exfat* ef, const struct exfat_node* dir,
                exfat_error("out of memory");
                return -ENOMEM;
        }
                exfat_error("out of memory");
                return -ENOMEM;
        }

-       exfat_read_raw(it->chunk, CLUSTER_SIZE(*ef->sb),
-                       exfat_c2o(ef, it->cluster), ef->fd);
+       if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+                       exfat_c2o(ef, it->cluster)) < 0)
+       {
+               exfat_error("failed to read directory cluster %#x", it->cluster);
+               return -EIO;
+       }

        return 0;
 }
 
        return 0;
 }
 


@@ -100,14 +116,24 @@ static int fetch_next_entry(struct exfat* ef, const struct exfat_node* parent,
        /* fetch the next cluster if needed */
        if ((it->offset & (CLUSTER_SIZE(*ef->sb) - 1)) == 0)
        {
        /* fetch the next cluster if needed */
        if ((it->offset & (CLUSTER_SIZE(*ef->sb) - 1)) == 0)
        {

+               /* reached the end of directory; the caller should check this
+                  condition too */
+               if (it->offset >= parent->size)
+                       return 0;

                it->cluster = exfat_next_cluster(ef, parent, it->cluster);
                if (CLUSTER_INVALID(it->cluster))
                {
                it->cluster = exfat_next_cluster(ef, parent, it->cluster);
                if (CLUSTER_INVALID(it->cluster))
                {

-                       exfat_error("invalid cluster while reading directory");
+                       exfat_error("invalid cluster 0x%x while reading directory",
+                                       it->cluster);
+                       return 1;
+               }
+               if (exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+                               exfat_c2o(ef, it->cluster)) < 0)
+               {
+                       exfat_error("failed to read the next directory cluster %#x",
+                                       it->cluster);

                        return 1;
                }
                        return 1;
                }

-               exfat_read_raw(it->chunk, CLUSTER_SIZE(*ef->sb),
-                               exfat_c2o(ef, it->cluster), ef->fd);

        }
        return 0;
 }
        }
        return 0;
 }


@@ -128,8 +154,10 @@ static void init_node_meta1(struct exfat_node* node,
                const struct exfat_entry_meta1* meta1)
 {
        node->flags = le16_to_cpu(meta1->attrib);
                const struct exfat_entry_meta1* meta1)
 {
        node->flags = le16_to_cpu(meta1->attrib);

-       node->mtime = exfat_exfat2unix(meta1->mdate, meta1->mtime);
-       node->atime = exfat_exfat2unix(meta1->adate, meta1->atime);
+       node->mtime = exfat_exfat2unix(meta1->mdate, meta1->mtime,
+                       meta1->mtime_cs);
+       /* there is no centiseconds field for atime */
+       node->atime = exfat_exfat2unix(meta1->adate, meta1->atime, 0);

 }
 
 static void init_node_meta2(struct exfat_node* node,
 }
 
 static void init_node_meta2(struct exfat_node* node,


@@ -138,10 +166,49 @@ static void init_node_meta2(struct exfat_node* node,
        node->size = le64_to_cpu(meta2->size);
        node->start_cluster = le32_to_cpu(meta2->start_cluster);
        node->fptr_cluster = node->start_cluster;
        node->size = le64_to_cpu(meta2->size);
        node->start_cluster = le32_to_cpu(meta2->start_cluster);
        node->fptr_cluster = node->start_cluster;

-       if (meta2->flag == EXFAT_FLAG_CONTIGUOUS)
+       if (meta2->flags & EXFAT_FLAG_CONTIGUOUS)

                node->flags |= EXFAT_ATTRIB_CONTIGUOUS;
 }
 
                node->flags |= EXFAT_ATTRIB_CONTIGUOUS;
 }
 

+static const struct exfat_entry* get_entry_ptr(const struct exfat* ef,
+               const struct iterator* it)
+{
+       return (const struct exfat_entry*)
+                       (it->chunk + it->offset % CLUSTER_SIZE(*ef->sb));
+}
+
+static bool check_node(const struct exfat_node* node, uint16_t actual_checksum,
+               uint16_t reference_checksum, uint64_t real_size)
+{
+       char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+
+       /*
+          Validate checksum first. If it's invalid all other fields probably
+          contain just garbage.
+       */
+       if (actual_checksum != reference_checksum)
+       {
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);
+               exfat_error("`%s' has invalid checksum (%#hx != %#hx)", buffer,
+                               actual_checksum, reference_checksum);
+               return false;
+       }
+
+       /*
+          It's unclear what is real_size field needed for. It usually equals to
+          the size but may contain any value less than size (including 0).
+       */
+       if (real_size > node->size)
+       {
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);
+               exfat_error("`%s' has real size (%"PRIu64") greater than size "
+                               "(%"PRIu64")", buffer, real_size, node->size);
+               return false;
+       }
+
+       return true;
+}
+

 /*
  * Reads one entry in directory at position pointed by iterator and fills
  * node structure.
 /*
  * Reads one entry in directory at position pointed by iterator and fills
  * node structure.


@@ -149,6 +216,7 @@ static void init_node_meta2(struct exfat_node* node,
 static int readdir(struct exfat* ef, const struct exfat_node* parent,
                struct exfat_node** node, struct iterator* it)
 {
 static int readdir(struct exfat* ef, const struct exfat_node* parent,
                struct exfat_node** node, struct iterator* it)
 {

+       int rc = -EIO;

        const struct exfat_entry* entry;
        const struct exfat_entry_meta1* meta1;
        const struct exfat_entry_meta2* meta2;
        const struct exfat_entry* entry;
        const struct exfat_entry_meta1* meta1;
        const struct exfat_entry_meta2* meta2;


@@ -160,27 +228,25 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
        le16_t* namep = NULL;
        uint16_t reference_checksum = 0;
        uint16_t actual_checksum = 0;
        le16_t* namep = NULL;
        uint16_t reference_checksum = 0;
        uint16_t actual_checksum = 0;

+       uint64_t real_size = 0;

 
        *node = NULL;
 
        for (;;)
        {
 
        *node = NULL;
 
        for (;;)
        {

-               /* every directory (even empty one) occupies at least one cluster and
-                  must contain EOD entry */
-               entry = (const struct exfat_entry*)
-                               (it->chunk + it->offset % CLUSTER_SIZE(*ef->sb));
-
-               switch (entry->type)
+               if (it->offset >= parent->size)

                {
                {

-               case EXFAT_ENTRY_EOD:

                        if (continuations != 0)
                        {
                        if (continuations != 0)
                        {

-                               exfat_error("expected %hhu continuations before EOD",
-                                               continuations);
+                               exfat_error("expected %hhu continuations", continuations);

                                goto error;
                        }
                        return -ENOENT; /* that's OK, means end of directory */
                                goto error;
                        }
                        return -ENOENT; /* that's OK, means end of directory */

+               }

 
 

+               entry = get_entry_ptr(ef, it);
+               switch (entry->type)
+               {

                case EXFAT_ENTRY_FILE:
                        if (continuations != 0)
                        {
                case EXFAT_ENTRY_FILE:
                        if (continuations != 0)
                        {


@@ -195,16 +261,25 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        if (continuations < 2)
                        {
                                exfat_error("too few continuations (%hhu)", continuations);
                        if (continuations < 2)
                        {
                                exfat_error("too few continuations (%hhu)", continuations);

-                               return -EIO;
+                               goto error;
+                       }
+                       if (continuations > 1 +
+                                       DIV_ROUND_UP(EXFAT_NAME_MAX, EXFAT_ENAME_MAX))
+                       {
+                               exfat_error("too many continuations (%hhu)", continuations);
+                               goto error;

                        }
                        reference_checksum = le16_to_cpu(meta1->checksum);
                        actual_checksum = exfat_start_checksum(meta1);
                        *node = allocate_node();
                        if (*node == NULL)
                        }
                        reference_checksum = le16_to_cpu(meta1->checksum);
                        actual_checksum = exfat_start_checksum(meta1);
                        *node = allocate_node();
                        if (*node == NULL)

-                               return -ENOMEM;
+                       {
+                               rc = -ENOMEM;
+                               goto error;
+                       }

                        /* new node has zero reference counter */
                        (*node)->entry_cluster = it->cluster;
                        /* new node has zero reference counter */
                        (*node)->entry_cluster = it->cluster;

-                       (*node)->entry_offset = it->offset % CLUSTER_SIZE(*ef->sb);
+                       (*node)->entry_offset = it->offset;

                        init_node_meta1(*node, meta1);
                        namep = (*node)->name;
                        break;
                        init_node_meta1(*node, meta1);
                        namep = (*node)->name;
                        break;


@@ -217,29 +292,27 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                                goto error;
                        }
                        meta2 = (const struct exfat_entry_meta2*) entry;
                                goto error;
                        }
                        meta2 = (const struct exfat_entry_meta2*) entry;

+                       if (meta2->flags & ~(EXFAT_FLAG_ALWAYS1 | EXFAT_FLAG_CONTIGUOUS))
+                       {
+                               exfat_error("unknown flags in meta2 (0x%hhx)", meta2->flags);
+                               goto error;
+                       }

                        init_node_meta2(*node, meta2);
                        actual_checksum = exfat_add_checksum(entry, actual_checksum);
                        init_node_meta2(*node, meta2);
                        actual_checksum = exfat_add_checksum(entry, actual_checksum);

-                       /* There are two fields that contain file size. Maybe they plan
-                          to add compression support in the future and one of those
-                          fields is visible (uncompressed) size and the other is real
-                          (compressed) size. Anyway, currently it looks like exFAT does
-                          not support compression and both fields must be equal. */
-                       if (le64_to_cpu(meta2->real_size) != (*node)->size)
+                       real_size = le64_to_cpu(meta2->real_size);
+                       /* empty files must be marked as non-contiguous */
+                       if ((*node)->size == 0 && (meta2->flags & EXFAT_FLAG_CONTIGUOUS))

                        {
                        {

-                               exfat_error("real size does not equal to size "
-                                               "(%"PRIu64" != %"PRIu64")",
-                                               le64_to_cpu(meta2->real_size), (*node)->size);
+                               exfat_error("empty file marked as contiguous (0x%hhx)",
+                                               meta2->flags);

                                goto error;
                        }
                        /* directories must be aligned on at cluster boundary */
                        if (((*node)->flags & EXFAT_ATTRIB_DIR) &&
                                (*node)->size % CLUSTER_SIZE(*ef->sb) != 0)
                        {
                                goto error;
                        }
                        /* directories must be aligned on at cluster boundary */
                        if (((*node)->flags & EXFAT_ATTRIB_DIR) &&
                                (*node)->size % CLUSTER_SIZE(*ef->sb) != 0)
                        {

-                               char buffer[EXFAT_NAME_MAX + 1];
-
-                               exfat_get_name(*node, buffer, EXFAT_NAME_MAX);
-                               exfat_error("directory `%s' has invalid size %"PRIu64" bytes",
-                                               buffer, (*node)->size);
+                               exfat_error("directory has invalid size %"PRIu64" bytes",
+                                               (*node)->size);

                                goto error;
                        }
                        --continuations;
                                goto error;
                        }
                        --continuations;


@@ -254,16 +327,16 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        file_name = (const struct exfat_entry_name*) entry;
                        actual_checksum = exfat_add_checksum(entry, actual_checksum);
 
                        file_name = (const struct exfat_entry_name*) entry;
                        actual_checksum = exfat_add_checksum(entry, actual_checksum);
 

-                       memcpy(namep, file_name->name, EXFAT_ENAME_MAX * sizeof(le16_t));
+                       memcpy(namep, file_name->name,
+                                       MIN(EXFAT_ENAME_MAX,
+                                               ((*node)->name + EXFAT_NAME_MAX - namep)) *
+                                       sizeof(le16_t));

                        namep += EXFAT_ENAME_MAX;
                        if (--continuations == 0)
                        {
                        namep += EXFAT_ENAME_MAX;
                        if (--continuations == 0)
                        {

-                               if (actual_checksum != reference_checksum)
-                               {
-                                       exfat_error("invalid checksum (0x%hx != 0x%hx)",
-                                                       actual_checksum, reference_checksum);
-                                       return -EIO;
-                               }
+                               if (!check_node(*node, actual_checksum, reference_checksum,
+                                               real_size))
+                                       goto error;

                                if (fetch_next_entry(ef, parent, it) != 0)
                                        goto error;
                                return 0; /* entry completed */
                                if (fetch_next_entry(ef, parent, it) != 0)
                                        goto error;
                                return 0; /* entry completed */


@@ -276,8 +349,9 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        upcase = (const struct exfat_entry_upcase*) entry;
                        if (CLUSTER_INVALID(le32_to_cpu(upcase->start_cluster)))
                        {
                        upcase = (const struct exfat_entry_upcase*) entry;
                        if (CLUSTER_INVALID(le32_to_cpu(upcase->start_cluster)))
                        {

-                               exfat_error("invalid cluster in upcase table");
-                               return -EIO;
+                               exfat_error("invalid cluster 0x%x in upcase table",
+                                               le32_to_cpu(upcase->start_cluster));
+                               goto error;

                        }
                        if (le64_to_cpu(upcase->size) == 0 ||
                                le64_to_cpu(upcase->size) > 0xffff * sizeof(uint16_t) ||
                        }
                        if (le64_to_cpu(upcase->size) == 0 ||
                                le64_to_cpu(upcase->size) > 0xffff * sizeof(uint16_t) ||


@@ -285,49 +359,68 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        {
                                exfat_error("bad upcase table size (%"PRIu64" bytes)",
                                                le64_to_cpu(upcase->size));
                        {
                                exfat_error("bad upcase table size (%"PRIu64" bytes)",
                                                le64_to_cpu(upcase->size));

-                               return -EIO;
+                               goto error;

                        }
                        ef->upcase = malloc(le64_to_cpu(upcase->size));
                        if (ef->upcase == NULL)
                        {
                                exfat_error("failed to allocate upcase table (%"PRIu64" bytes)",
                                                le64_to_cpu(upcase->size));
                        }
                        ef->upcase = malloc(le64_to_cpu(upcase->size));
                        if (ef->upcase == NULL)
                        {
                                exfat_error("failed to allocate upcase table (%"PRIu64" bytes)",
                                                le64_to_cpu(upcase->size));

-                               return -ENOMEM;
+                               rc = -ENOMEM;
+                               goto error;

                        }
                        ef->upcase_chars = le64_to_cpu(upcase->size) / sizeof(le16_t);
 
                        }
                        ef->upcase_chars = le64_to_cpu(upcase->size) / sizeof(le16_t);
 

-                       exfat_read_raw(ef->upcase, le64_to_cpu(upcase->size),
-                                       exfat_c2o(ef, le32_to_cpu(upcase->start_cluster)), ef->fd);
+                       if (exfat_pread(ef->dev, ef->upcase, le64_to_cpu(upcase->size),
+                                       exfat_c2o(ef, le32_to_cpu(upcase->start_cluster))) < 0)
+                       {
+                               exfat_error("failed to read upper case table "
+                                               "(%"PRIu64" bytes starting at cluster %#x)",
+                                               le64_to_cpu(upcase->size),
+                                               le32_to_cpu(upcase->start_cluster));
+                               goto error;
+                       }

                        break;
 
                case EXFAT_ENTRY_BITMAP:
                        bitmap = (const struct exfat_entry_bitmap*) entry;
                        break;
 
                case EXFAT_ENTRY_BITMAP:
                        bitmap = (const struct exfat_entry_bitmap*) entry;

-                       if (CLUSTER_INVALID(le32_to_cpu(bitmap->start_cluster)))
+                       ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
+                       if (CLUSTER_INVALID(ef->cmap.start_cluster))

                        {
                        {

-                               exfat_error("invalid cluster in clusters bitmap");
-                               return -EIO;
+                               exfat_error("invalid cluster 0x%x in clusters bitmap",
+                                               ef->cmap.start_cluster);
+                               goto error;

                        }
                        ef->cmap.size = le32_to_cpu(ef->sb->cluster_count) -
                                EXFAT_FIRST_DATA_CLUSTER;
                        }
                        ef->cmap.size = le32_to_cpu(ef->sb->cluster_count) -
                                EXFAT_FIRST_DATA_CLUSTER;

-                       if (le64_to_cpu(bitmap->size) != (ef->cmap.size + 7) / 8)
+                       if (le64_to_cpu(bitmap->size) < DIV_ROUND_UP(ef->cmap.size, 8))

                        {
                        {

-                               exfat_error("invalid bitmap size: %"PRIu64" (expected %u)",
-                                               le64_to_cpu(bitmap->size), (ef->cmap.size + 7) / 8);
-                               return -EIO;
+                               exfat_error("invalid clusters bitmap size: %"PRIu64
+                                               " (expected at least %u)",
+                                               le64_to_cpu(bitmap->size),
+                                               DIV_ROUND_UP(ef->cmap.size, 8));
+                               goto error;

                        }
                        }

-                       ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);

                        /* FIXME bitmap can be rather big, up to 512 MB */
                        ef->cmap.chunk_size = ef->cmap.size;
                        /* FIXME bitmap can be rather big, up to 512 MB */
                        ef->cmap.chunk_size = ef->cmap.size;

-                       ef->cmap.chunk = malloc(le64_to_cpu(bitmap->size));
+                       ef->cmap.chunk = malloc(BMAP_SIZE(ef->cmap.chunk_size));

                        if (ef->cmap.chunk == NULL)
                        {
                        if (ef->cmap.chunk == NULL)
                        {

-                               exfat_error("failed to allocate clusters map chunk "
+                               exfat_error("failed to allocate clusters bitmap chunk "

                                                "(%"PRIu64" bytes)", le64_to_cpu(bitmap->size));
                                                "(%"PRIu64" bytes)", le64_to_cpu(bitmap->size));

-                               return -ENOMEM;
+                               rc = -ENOMEM;
+                               goto error;

                        }
 
                        }
 

-                       exfat_read_raw(ef->cmap.chunk, le64_to_cpu(bitmap->size),
-                                       exfat_c2o(ef, ef->cmap.start_cluster), ef->fd);
+                       if (exfat_pread(ef->dev, ef->cmap.chunk,
+                                       BMAP_SIZE(ef->cmap.chunk_size),
+                                       exfat_c2o(ef, ef->cmap.start_cluster)) < 0)
+                       {
+                               exfat_error("failed to read clusters bitmap "
+                                               "(%"PRIu64" bytes starting at cluster %#x)",
+                                               le64_to_cpu(bitmap->size), ef->cmap.start_cluster);
+                               goto error;
+                       }

                        break;
 
                case EXFAT_ENTRY_LABEL:
                        break;
 
                case EXFAT_ENTRY_LABEL:


@@ -335,14 +428,17 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
                        if (label->length > EXFAT_ENAME_MAX)
                        {
                                exfat_error("too long label (%hhu chars)", label->length);
                        if (label->length > EXFAT_ENAME_MAX)
                        {
                                exfat_error("too long label (%hhu chars)", label->length);

-                               return -EIO;
+                               goto error;

                        }
                        }

+                       if (utf16_to_utf8(ef->label, label->name,
+                                               sizeof(ef->label) - 1, EXFAT_ENAME_MAX) != 0)
+                               goto error;

                        break;
 
                default:
                        if (entry->type & EXFAT_ENTRY_VALID)
                        {
                        break;
 
                default:
                        if (entry->type & EXFAT_ENTRY_VALID)
                        {

-                               exfat_error("unknown entry type 0x%hhu", entry->type);
+                               exfat_error("unknown entry type 0x%hhx", entry->type);

                                goto error;
                        }
                        break;
                                goto error;
                        }
                        break;


@@ -356,7 +452,7 @@ static int readdir(struct exfat* ef, const struct exfat_node* parent,
 error:
        free(*node);
        *node = NULL;
 error:
        free(*node);
        *node = NULL;

-       return -EIO;
+       return rc;

 }
 
 int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
 }
 
 int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)


@@ -403,28 +499,49 @@ int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
        return 0;
 }
 
        return 0;
 }
 

-static void reset_cache(struct exfat* ef, struct exfat_node* node)
+static void tree_attach(struct exfat_node* dir, struct exfat_node* node)
+{
+       node->parent = dir;
+       if (dir->child)
+       {
+               dir->child->prev = node;
+               node->next = dir->child;
+       }
+       dir->child = node;
+}
+
+static void tree_detach(struct exfat_node* node)

 {
 {

-       struct exfat_node* child;
-       struct exfat_node* next;
+       if (node->prev)
+               node->prev->next = node->next;
+       else /* this is the first node in the list */
+               node->parent->child = node->next;
+       if (node->next)
+               node->next->prev = node->prev;
+       node->parent = NULL;
+       node->prev = NULL;
+       node->next = NULL;
+}

 
 

-       for (child = node->child; child; child = next)
+static void reset_cache(struct exfat* ef, struct exfat_node* node)
+{
+       while (node->child)

        {
        {

-               reset_cache(ef, child);
-               next = child->next;
-               free(child);
+               struct exfat_node* p = node->child;
+               reset_cache(ef, p);
+               tree_detach(p);
+               free(p);

        }
        }

+       node->flags &= ~EXFAT_ATTRIB_CACHED;

        if (node->references != 0)
        {
        if (node->references != 0)
        {

-               char buffer[EXFAT_NAME_MAX + 1];
-               exfat_get_name(node, buffer, EXFAT_NAME_MAX);
+               char buffer[UTF8_BYTES(EXFAT_NAME_MAX) + 1];
+               exfat_get_name(node, buffer, sizeof(buffer) - 1);

                exfat_warn("non-zero reference counter (%d) for `%s'",
                                node->references, buffer);
        }
                exfat_warn("non-zero reference counter (%d) for `%s'",
                                node->references, buffer);
        }

-       while (node->references--)
+       while (node->references)

                exfat_put_node(ef, node);
                exfat_put_node(ef, node);

-       node->child = NULL;
-       node->flags &= ~EXFAT_ATTRIB_CACHED;

 }
 
 void exfat_reset_cache(struct exfat* ef)
 }
 
 void exfat_reset_cache(struct exfat* ef)


@@ -432,21 +549,24 @@ void exfat_reset_cache(struct exfat* ef)
        reset_cache(ef, ef->root);
 }
 
        reset_cache(ef, ef->root);
 }
 

-void next_entry(struct exfat* ef, const struct exfat_node* parent,
+static bool next_entry(struct exfat* ef, const struct exfat_node* parent,

                cluster_t* cluster, off_t* offset)
 {
                cluster_t* cluster, off_t* offset)
 {

-       if (*offset + sizeof(struct exfat_entry) == CLUSTER_SIZE(*ef->sb))
+       *offset += sizeof(struct exfat_entry);
+       if (*offset % CLUSTER_SIZE(*ef->sb) == 0)

        {
        {

-               /* next cluster cannot be invalid */

                *cluster = exfat_next_cluster(ef, parent, *cluster);
                *cluster = exfat_next_cluster(ef, parent, *cluster);

-               *offset = 0;
+               if (CLUSTER_INVALID(*cluster))
+               {
+                       exfat_error("invalid cluster %#x while getting next entry",
+                                       *cluster);
+                       return false;
+               }

        }
        }

-       else
-               *offset += sizeof(struct exfat_entry);
-
+       return true;

 }
 
 }
 

-void exfat_flush_node(struct exfat* ef, struct exfat_node* node)
+int exfat_flush_node(struct exfat* ef, struct exfat_node* node)

 {
        cluster_t cluster;
        off_t offset;
 {
        cluster_t cluster;
        off_t offset;


@@ -454,46 +574,66 @@ void exfat_flush_node(struct exfat* ef, struct exfat_node* node)
        struct exfat_entry_meta1 meta1;
        struct exfat_entry_meta2 meta2;
 
        struct exfat_entry_meta1 meta1;
        struct exfat_entry_meta2 meta2;
 

+       if (!(node->flags & EXFAT_ATTRIB_DIRTY))
+               return 0; /* no need to flush */
+

        if (ef->ro)
                exfat_bug("unable to flush node to read-only FS");
 
        if (node->parent == NULL)
        if (ef->ro)
                exfat_bug("unable to flush node to read-only FS");
 
        if (node->parent == NULL)

-               return; /* do not flush unlinked node */
+               return 0; /* do not flush unlinked node */

 
        cluster = node->entry_cluster;
        offset = node->entry_offset;
 
        cluster = node->entry_cluster;
        offset = node->entry_offset;

-       meta1_offset = exfat_c2o(ef, cluster) + offset;
-       next_entry(ef, node->parent, &cluster, &offset);
-       meta2_offset = exfat_c2o(ef, cluster) + offset;
+       meta1_offset = co2o(ef, cluster, offset);
+       if (!next_entry(ef, node->parent, &cluster, &offset))
+               return -EIO;
+       meta2_offset = co2o(ef, cluster, offset);

 
 

-       exfat_read_raw(&meta1, sizeof(meta1), meta1_offset, ef->fd);
+       if (exfat_pread(ef->dev, &meta1, sizeof(meta1), meta1_offset) < 0)
+       {
+               exfat_error("failed to read meta1 entry on flush");
+               return -EIO;
+       }

        if (meta1.type != EXFAT_ENTRY_FILE)
                exfat_bug("invalid type of meta1: 0x%hhx", meta1.type);
        meta1.attrib = cpu_to_le16(node->flags);
        if (meta1.type != EXFAT_ENTRY_FILE)
                exfat_bug("invalid type of meta1: 0x%hhx", meta1.type);
        meta1.attrib = cpu_to_le16(node->flags);

-       exfat_unix2exfat(node->mtime, &meta1.mdate, &meta1.mtime);
-       exfat_unix2exfat(node->atime, &meta1.adate, &meta1.atime);
+       exfat_unix2exfat(node->mtime, &meta1.mdate, &meta1.mtime, &meta1.mtime_cs);
+       exfat_unix2exfat(node->atime, &meta1.adate, &meta1.atime, NULL);

 
 

-       exfat_read_raw(&meta2, sizeof(meta2), meta2_offset, ef->fd);
+       if (exfat_pread(ef->dev, &meta2, sizeof(meta2), meta2_offset) < 0)
+       {
+               exfat_error("failed to read meta2 entry on flush");
+               return -EIO;
+       }

        if (meta2.type != EXFAT_ENTRY_FILE_INFO)
                exfat_bug("invalid type of meta2: 0x%hhx", meta2.type);
        meta2.size = meta2.real_size = cpu_to_le64(node->size);
        meta2.start_cluster = cpu_to_le32(node->start_cluster);
        if (meta2.type != EXFAT_ENTRY_FILE_INFO)
                exfat_bug("invalid type of meta2: 0x%hhx", meta2.type);
        meta2.size = meta2.real_size = cpu_to_le64(node->size);
        meta2.start_cluster = cpu_to_le32(node->start_cluster);

-       /* empty files must be marked as fragmented */
+       meta2.flags = EXFAT_FLAG_ALWAYS1;
+       /* empty files must not be marked as contiguous */

        if (node->size != 0 && IS_CONTIGUOUS(*node))
        if (node->size != 0 && IS_CONTIGUOUS(*node))

-               meta2.flag = EXFAT_FLAG_CONTIGUOUS;
-       else
-               meta2.flag = EXFAT_FLAG_FRAGMENTED;
+               meta2.flags |= EXFAT_FLAG_CONTIGUOUS;

        /* name hash remains unchanged, no need to recalculate it */
 
        meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
 
        /* name hash remains unchanged, no need to recalculate it */
 
        meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
 

-       exfat_write_raw(&meta1, sizeof(meta1), meta1_offset, ef->fd);
-       exfat_write_raw(&meta2, sizeof(meta2), meta2_offset, ef->fd);
+       if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1), meta1_offset) < 0)
+       {
+               exfat_error("failed to write meta1 entry on flush");
+               return -EIO;
+       }
+       if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2), meta2_offset) < 0)
+       {
+               exfat_error("failed to write meta2 entry on flush");
+               return -EIO;
+       }

 
        node->flags &= ~EXFAT_ATTRIB_DIRTY;
 
        node->flags &= ~EXFAT_ATTRIB_DIRTY;

+       return 0;

 }
 
 }
 

-static void erase_entry(struct exfat* ef, struct exfat_node* node)
+static bool erase_entry(struct exfat* ef, struct exfat_node* node)

 {
        cluster_t cluster = node->entry_cluster;
        off_t offset = node->entry_offset;
 {
        cluster_t cluster = node->entry_cluster;
        off_t offset = node->entry_offset;


@@ -501,60 +641,107 @@ static void erase_entry(struct exfat* ef, struct exfat_node* node)
        uint8_t entry_type;
 
        entry_type = EXFAT_ENTRY_FILE & ~EXFAT_ENTRY_VALID;
        uint8_t entry_type;
 
        entry_type = EXFAT_ENTRY_FILE & ~EXFAT_ENTRY_VALID;

-       exfat_write_raw(&entry_type, 1, exfat_c2o(ef, cluster) + offset, ef->fd);
+       if (exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset)) < 0)
+       {
+               exfat_error("failed to erase meta1 entry");
+               return false;
+       }

 
 

-       next_entry(ef, node->parent, &cluster, &offset);
+       if (!next_entry(ef, node->parent, &cluster, &offset))
+               return false;

        entry_type = EXFAT_ENTRY_FILE_INFO & ~EXFAT_ENTRY_VALID;
        entry_type = EXFAT_ENTRY_FILE_INFO & ~EXFAT_ENTRY_VALID;

-       exfat_write_raw(&entry_type, 1, exfat_c2o(ef, cluster) + offset, ef->fd);
+       if (exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset)) < 0)
+       {
+               exfat_error("failed to erase meta2 entry");
+               return false;
+       }

 
        while (name_entries--)
        {
 
        while (name_entries--)
        {

-               next_entry(ef, node->parent, &cluster, &offset);
+               if (!next_entry(ef, node->parent, &cluster, &offset))
+                       return false;

                entry_type = EXFAT_ENTRY_FILE_NAME & ~EXFAT_ENTRY_VALID;
                entry_type = EXFAT_ENTRY_FILE_NAME & ~EXFAT_ENTRY_VALID;

-               exfat_write_raw(&entry_type, 1, exfat_c2o(ef, cluster) + offset,
-                               ef->fd);
+               if (exfat_pwrite(ef->dev, &entry_type, 1,
+                               co2o(ef, cluster, offset)) < 0)
+               {
+                       exfat_error("failed to erase name entry");
+                       return false;
+               }

        }
        }

+       return true;

 }
 
 }
 

-static void tree_detach(struct exfat_node* node)
+static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
+               off_t deleted_offset)

 {
 {

-       if (node->prev)
-               node->prev->next = node->next;
-       else /* this is the first node in the list */
-               node->parent->child = node->next;
-       if (node->next)
-               node->next->prev = node->prev;
-       node->parent = NULL;
-       node->prev = NULL;
-       node->next = NULL;
-}
+       const struct exfat_node* node;
+       const struct exfat_node* last_node;
+       uint64_t entries = 0;
+       uint64_t new_size;

 
 

-static void tree_attach(struct exfat_node* dir, struct exfat_node* node)
-{
-       node->parent = dir;
-       if (dir->child)
+       if (!(dir->flags & EXFAT_ATTRIB_DIR))
+               exfat_bug("attempted to shrink a file");
+       if (!(dir->flags & EXFAT_ATTRIB_CACHED))
+               exfat_bug("attempted to shrink uncached directory");
+
+       for (last_node = node = dir->child; node; node = node->next)

        {
        {

-               dir->child->prev = node;
-               node->next = dir->child;
+               if (deleted_offset < node->entry_offset)
+               {
+                       /* there are other entries after the removed one, no way to shrink
+                          this directory */
+                       return 0;
+               }
+               if (last_node->entry_offset < node->entry_offset)
+                       last_node = node;

        }
        }

-       dir->child = node;
+
+       if (last_node)
+       {
+               /* offset of the last entry */
+               entries += last_node->entry_offset / sizeof(struct exfat_entry);
+               /* two subentries with meta info */
+               entries += 2;
+               /* subentries with file name */
+               entries += DIV_ROUND_UP(utf16_length(last_node->name),
+                               EXFAT_ENAME_MAX);
+       }
+
+       new_size = DIV_ROUND_UP(entries * sizeof(struct exfat_entry),
+                                CLUSTER_SIZE(*ef->sb)) * CLUSTER_SIZE(*ef->sb);
+       if (new_size == 0) /* directory always has at least 1 cluster */
+               new_size = CLUSTER_SIZE(*ef->sb);
+       if (new_size == dir->size)
+               return 0;
+       return exfat_truncate(ef, dir, new_size, true);

 }
 
 }
 

-static void delete(struct exfat* ef, struct exfat_node* node)
+static int delete(struct exfat* ef, struct exfat_node* node)

 {
 {

-       erase_entry(ef, node);
-       exfat_update_mtime(node->parent);
+       struct exfat_node* parent = node->parent;
+       off_t deleted_offset = node->entry_offset;
+       int rc;
+
+       exfat_get_node(parent);
+       if (!erase_entry(ef, node))
+       {
+               exfat_put_node(ef, parent);
+               return -EIO;
+       }
+       exfat_update_mtime(parent);

        tree_detach(node);
        tree_detach(node);

+       rc = shrink_directory(ef, parent, deleted_offset);
+       exfat_put_node(ef, parent);

        /* file clusters will be freed when node reference counter becomes 0 */
        node->flags |= EXFAT_ATTRIB_UNLINKED;
        /* file clusters will be freed when node reference counter becomes 0 */
        node->flags |= EXFAT_ATTRIB_UNLINKED;

+       return rc;

 }
 
 int exfat_unlink(struct exfat* ef, struct exfat_node* node)
 {
        if (node->flags & EXFAT_ATTRIB_DIR)
                return -EISDIR;
 }
 
 int exfat_unlink(struct exfat* ef, struct exfat_node* node)
 {
        if (node->flags & EXFAT_ATTRIB_DIR)
                return -EISDIR;

-       delete(ef, node);
-       return 0;
+       return delete(ef, node);

 }
 
 int exfat_rmdir(struct exfat* ef, struct exfat_node* node)
 }
 
 int exfat_rmdir(struct exfat* ef, struct exfat_node* node)


@@ -565,8 +752,7 @@ int exfat_rmdir(struct exfat* ef, struct exfat_node* node)
        exfat_cache_directory(ef, node);
        if (node->child)
                return -ENOTEMPTY;
        exfat_cache_directory(ef, node);
        if (node->child)
                return -ENOTEMPTY;

-       delete(ef, node);
-       return 0;
+       return delete(ef, node);

 }
 
 static int grow_directory(struct exfat* ef, struct exfat_node* dir,
 }
 
 static int grow_directory(struct exfat* ef, struct exfat_node* dir,


@@ -574,7 +760,7 @@ static int grow_directory(struct exfat* ef, struct exfat_node* dir,
 {
        return exfat_truncate(ef, dir,
                        DIV_ROUND_UP(asize + difference, CLUSTER_SIZE(*ef->sb))
 {
        return exfat_truncate(ef, dir,
                        DIV_ROUND_UP(asize + difference, CLUSTER_SIZE(*ef->sb))

-                               * CLUSTER_SIZE(*ef->sb));
+                               * CLUSTER_SIZE(*ef->sb), true);

 }
 
 static int find_slot(struct exfat* ef, struct exfat_node* dir,
 }
 
 static int find_slot(struct exfat* ef, struct exfat_node* dir,


@@ -593,28 +779,25 @@ static int find_slot(struct exfat* ef, struct exfat_node* dir,
                if (contiguous == 0)
                {
                        *cluster = it.cluster;
                if (contiguous == 0)
                {
                        *cluster = it.cluster;

-                       *offset = it.offset % CLUSTER_SIZE(*ef->sb);
+                       *offset = it.offset;

                }
                }

-               entry = (const struct exfat_entry*)
-                               (it.chunk + it.offset % CLUSTER_SIZE(*ef->sb));
-               if (entry->type == EXFAT_ENTRY_EOD)
+               entry = get_entry_ptr(ef, &it);
+               if (entry->type & EXFAT_ENTRY_VALID)
+                       contiguous = 0;
+               else
+                       contiguous++;
+               if (contiguous == subentries)
+                       break;  /* suitable slot is found */
+               if (it.offset + sizeof(struct exfat_entry) >= dir->size)

                {
                {

-                       rc = grow_directory(ef, dir,
-                                       it.offset + sizeof(struct exfat_entry), /* actual size */
+                       rc = grow_directory(ef, dir, dir->size,

                                        (subentries - contiguous) * sizeof(struct exfat_entry));
                        if (rc != 0)
                        {
                                closedir(&it);
                                return rc;
                        }
                                        (subentries - contiguous) * sizeof(struct exfat_entry));
                        if (rc != 0)
                        {
                                closedir(&it);
                                return rc;
                        }

-                       break;

                }
                }

-               if (entry->type & EXFAT_ENTRY_VALID)
-                       contiguous = 0;
-               else
-                       contiguous++;
-               if (contiguous == subentries)
-                       break;  /* suitable slot it found */

                if (fetch_next_entry(ef, dir, &it) != 0)
                {
                        closedir(&it);
                if (fetch_next_entry(ef, dir, &it) != 0)
                {
                        closedir(&it);


@@ -646,34 +829,49 @@ static int write_entry(struct exfat* ef, struct exfat_node* dir,
        meta1.type = EXFAT_ENTRY_FILE;
        meta1.continuations = 1 + name_entries;
        meta1.attrib = cpu_to_le16(attrib);
        meta1.type = EXFAT_ENTRY_FILE;
        meta1.continuations = 1 + name_entries;
        meta1.attrib = cpu_to_le16(attrib);

-       exfat_unix2exfat(time(NULL), &meta1.crdate, &meta1.crtime);
+       exfat_unix2exfat(time(NULL), &meta1.crdate, &meta1.crtime,
+                       &meta1.crtime_cs);

        meta1.adate = meta1.mdate = meta1.crdate;
        meta1.atime = meta1.mtime = meta1.crtime;
        meta1.adate = meta1.mdate = meta1.crdate;
        meta1.atime = meta1.mtime = meta1.crtime;

-       /* crtime_cs and mtime_cs contain addition to the time in centiseconds;
-          just ignore those fields because we operate with 2 sec resolution */
+       meta1.mtime_cs = meta1.crtime_cs; /* there is no atime_cs */

 
        memset(&meta2, 0, sizeof(meta2));
        meta2.type = EXFAT_ENTRY_FILE_INFO;
 
        memset(&meta2, 0, sizeof(meta2));
        meta2.type = EXFAT_ENTRY_FILE_INFO;

-       meta2.flag = EXFAT_FLAG_FRAGMENTED;
+       meta2.flags = EXFAT_FLAG_ALWAYS1;

        meta2.name_length = name_length;
        meta2.name_hash = exfat_calc_name_hash(ef, node->name);
        meta2.start_cluster = cpu_to_le32(EXFAT_CLUSTER_FREE);
 
        meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
 
        meta2.name_length = name_length;
        meta2.name_hash = exfat_calc_name_hash(ef, node->name);
        meta2.start_cluster = cpu_to_le32(EXFAT_CLUSTER_FREE);
 
        meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
 

-       exfat_write_raw(&meta1, sizeof(meta1), exfat_c2o(ef, cluster) + offset,
-                       ef->fd);
-       next_entry(ef, dir, &cluster, &offset);
-       exfat_write_raw(&meta2, sizeof(meta2), exfat_c2o(ef, cluster) + offset,
-                       ef->fd);
+       if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+                       co2o(ef, cluster, offset)) < 0)
+       {
+               exfat_error("failed to write meta1 entry");
+               return -EIO;
+       }
+       if (!next_entry(ef, dir, &cluster, &offset))
+               return -EIO;
+       if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+                       co2o(ef, cluster, offset)) < 0)
+       {
+               exfat_error("failed to write meta2 entry");
+               return -EIO;
+       }

        for (i = 0; i < name_entries; i++)
        {
                struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
                memcpy(name_entry.name, node->name + i * EXFAT_ENAME_MAX,
        for (i = 0; i < name_entries; i++)
        {
                struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
                memcpy(name_entry.name, node->name + i * EXFAT_ENAME_MAX,

-                               EXFAT_ENAME_MAX * sizeof(le16_t));
-               next_entry(ef, dir, &cluster, &offset);
-               exfat_write_raw(&name_entry, sizeof(name_entry),
-                               exfat_c2o(ef, cluster) + offset, ef->fd);
+                               MIN(EXFAT_ENAME_MAX, EXFAT_NAME_MAX - i * EXFAT_ENAME_MAX) *
+                               sizeof(le16_t));
+               if (!next_entry(ef, dir, &cluster, &offset))
+                       return -EIO;
+               if (exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+                               co2o(ef, cluster, offset)) < 0)
+               {
+                       exfat_error("failed to write name entry");
+                       return -EIO;
+               }

        }
 
        init_node_meta1(node, &meta1);
        }
 
        init_node_meta1(node, &meta1);


@@ -687,14 +885,21 @@ static int write_entry(struct exfat* ef, struct exfat_node* dir,
 static int create(struct exfat* ef, const char* path, uint16_t attrib)
 {
        struct exfat_node* dir;
 static int create(struct exfat* ef, const char* path, uint16_t attrib)
 {
        struct exfat_node* dir;

+       struct exfat_node* existing;

        cluster_t cluster = EXFAT_CLUSTER_BAD;
        off_t offset = -1;
        le16_t name[EXFAT_NAME_MAX + 1];
        int rc;
 
        cluster_t cluster = EXFAT_CLUSTER_BAD;
        off_t offset = -1;
        le16_t name[EXFAT_NAME_MAX + 1];
        int rc;
 

-       rc = exfat_split(ef, &dir, name, path);
+       rc = exfat_split(ef, &dir, &existing, name, path);

        if (rc != 0)
                return rc;
        if (rc != 0)
                return rc;

+       if (existing != NULL)
+       {
+               exfat_put_node(ef, existing);
+               exfat_put_node(ef, dir);
+               return -EEXIST;
+       }

 
        rc = find_slot(ef, dir, &cluster, &offset,
                        2 + DIV_ROUND_UP(utf16_length(name), EXFAT_ENAME_MAX));
 
        rc = find_slot(ef, dir, &cluster, &offset,
                        2 + DIV_ROUND_UP(utf16_length(name), EXFAT_ENAME_MAX));


@@ -725,7 +930,7 @@ int exfat_mkdir(struct exfat* ef, const char* path)
        if (rc != 0)
                return 0;
        /* directories always have at least one cluster */
        if (rc != 0)
                return 0;
        /* directories always have at least one cluster */

-       rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb));
+       rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb), true);

        if (rc != 0)
        {
                delete(ef, node);
        if (rc != 0)
        {
                delete(ef, node);


@@ -736,7 +941,7 @@ int exfat_mkdir(struct exfat* ef, const char* path)
        return 0;
 }
 
        return 0;
 }
 

-static void rename_entry(struct exfat* ef, struct exfat_node* dir,
+static int rename_entry(struct exfat* ef, struct exfat_node* dir,

                struct exfat_node* node, const le16_t* name, cluster_t new_cluster,
                off_t new_offset)
 {
                struct exfat_node* node, const le16_t* name, cluster_t new_cluster,
                off_t new_offset)
 {


@@ -748,45 +953,71 @@ static void rename_entry(struct exfat* ef, struct exfat_node* dir,
        const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
        int i;
 
        const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
        int i;
 

-       exfat_read_raw(&meta1, sizeof(meta1),
-                       exfat_c2o(ef, old_cluster) + old_offset, ef->fd);
-       next_entry(ef, node->parent, &old_cluster, &old_offset);
-       exfat_read_raw(&meta2, sizeof(meta2),
-                       exfat_c2o(ef, old_cluster) + old_offset, ef->fd);
+       if (exfat_pread(ef->dev, &meta1, sizeof(meta1),
+                       co2o(ef, old_cluster, old_offset)) < 0)
+       {
+               exfat_error("failed to read meta1 entry on rename");
+               return -EIO;
+       }
+       if (!next_entry(ef, node->parent, &old_cluster, &old_offset))
+               return -EIO;
+       if (exfat_pread(ef->dev, &meta2, sizeof(meta2),
+                       co2o(ef, old_cluster, old_offset)) < 0)
+       {
+               exfat_error("failed to read meta2 entry on rename");
+               return -EIO;
+       }

        meta1.continuations = 1 + name_entries;
        meta2.name_hash = exfat_calc_name_hash(ef, name);
        meta2.name_length = name_length;
        meta1.checksum = exfat_calc_checksum(&meta1, &meta2, name);
 
        meta1.continuations = 1 + name_entries;
        meta2.name_hash = exfat_calc_name_hash(ef, name);
        meta2.name_length = name_length;
        meta1.checksum = exfat_calc_checksum(&meta1, &meta2, name);
 

-       erase_entry(ef, node);
+       if (!erase_entry(ef, node))
+               return -EIO;

 
        node->entry_cluster = new_cluster;
        node->entry_offset = new_offset;
 
 
        node->entry_cluster = new_cluster;
        node->entry_offset = new_offset;
 

-       exfat_write_raw(&meta1, sizeof(meta1),
-            exfat_c2o(ef, new_cluster) + new_offset, ef->fd);
-       next_entry(ef, dir, &new_cluster, &new_offset);
-       exfat_write_raw(&meta2, sizeof(meta2),
-            exfat_c2o(ef, new_cluster) + new_offset, ef->fd);
+       if (exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+                       co2o(ef, new_cluster, new_offset)) < 0)
+       {
+               exfat_error("failed to write meta1 entry on rename");
+               return -EIO;
+       }
+       if (!next_entry(ef, dir, &new_cluster, &new_offset))
+               return -EIO;
+       if (exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+                       co2o(ef, new_cluster, new_offset)) < 0)
+       {
+               exfat_error("failed to write meta2 entry on rename");
+               return -EIO;
+       }

 
        for (i = 0; i < name_entries; i++)
        {
                struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
                memcpy(name_entry.name, name + i * EXFAT_ENAME_MAX,
                                EXFAT_ENAME_MAX * sizeof(le16_t));
 
        for (i = 0; i < name_entries; i++)
        {
                struct exfat_entry_name name_entry = {EXFAT_ENTRY_FILE_NAME, 0};
                memcpy(name_entry.name, name + i * EXFAT_ENAME_MAX,
                                EXFAT_ENAME_MAX * sizeof(le16_t));

-               next_entry(ef, dir, &new_cluster, &new_offset);
-               exfat_write_raw(&name_entry, sizeof(name_entry),
-                               exfat_c2o(ef, new_cluster) + new_offset, ef->fd);
+               if (!next_entry(ef, dir, &new_cluster, &new_offset))
+                       return -EIO;
+               if (exfat_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+                               co2o(ef, new_cluster, new_offset)) < 0)
+               {
+                       exfat_error("failed to write name entry on rename");
+                       return -EIO;
+               }

        }
 
        }
 

-       memcpy(node->name, name, (name_length + 1) * sizeof(le16_t));
+       memcpy(node->name, name, (EXFAT_NAME_MAX + 1) * sizeof(le16_t));

        tree_detach(node);
        tree_attach(dir, node);
        tree_detach(node);
        tree_attach(dir, node);

+       return 0;

 }
 
 int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
 {
        struct exfat_node* node;
 }
 
 int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
 {
        struct exfat_node* node;

+       struct exfat_node* existing;

        struct exfat_node* dir;
        cluster_t cluster = EXFAT_CLUSTER_BAD;
        off_t offset = -1;
        struct exfat_node* dir;
        cluster_t cluster = EXFAT_CLUSTER_BAD;
        off_t offset = -1;


@@ -797,14 +1028,60 @@ int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
        if (rc != 0)
                return rc;
 
        if (rc != 0)
                return rc;
 

-       memset(name, 0, (EXFAT_NAME_MAX + 1) * sizeof(le16_t));
-       rc = exfat_split(ef, &dir, name, new_path);
+       rc = exfat_split(ef, &dir, &existing, name, new_path);

        if (rc != 0)
        {
                exfat_put_node(ef, node);
                return rc;
        }
 
        if (rc != 0)
        {
                exfat_put_node(ef, node);
                return rc;
        }
 

+       /* check that target is not a subdirectory of the source */
+       if (node->flags & EXFAT_ATTRIB_DIR)
+       {
+               struct exfat_node* p;
+
+               for (p = dir; p; p = p->parent)
+                       if (node == p)
+                       {
+                               if (existing != NULL)
+                                       exfat_put_node(ef, existing);
+                               exfat_put_node(ef, dir);
+                               exfat_put_node(ef, node);
+                               return -EINVAL;
+                       }
+       }
+
+       if (existing != NULL)
+       {
+               /* remove target if it's not the same node as source */
+               if (existing != node)
+               {
+                       if (existing->flags & EXFAT_ATTRIB_DIR)
+                       {
+                               if (node->flags & EXFAT_ATTRIB_DIR)
+                                       rc = exfat_rmdir(ef, existing);
+                               else
+                                       rc = -ENOTDIR;
+                       }
+                       else
+                       {
+                               if (!(node->flags & EXFAT_ATTRIB_DIR))
+                                       rc = exfat_unlink(ef, existing);
+                               else
+                                       rc = -EISDIR;
+                       }
+                       exfat_put_node(ef, existing);
+                       if (rc != 0)
+                       {
+                               exfat_put_node(ef, dir);
+                               exfat_put_node(ef, node);
+                               return rc;
+                       }
+               }
+               else
+                       exfat_put_node(ef, existing);
+       }
+

        rc = find_slot(ef, dir, &cluster, &offset,
                        2 + DIV_ROUND_UP(utf16_length(name), EXFAT_ENAME_MAX));
        if (rc != 0)
        rc = find_slot(ef, dir, &cluster, &offset,
                        2 + DIV_ROUND_UP(utf16_length(name), EXFAT_ENAME_MAX));
        if (rc != 0)


@@ -813,7 +1090,7 @@ int exfat_rename(struct exfat* ef, const char* old_path, const char* new_path)
                exfat_put_node(ef, node);
                return rc;
        }
                exfat_put_node(ef, node);
                return rc;
        }

-       rename_entry(ef, dir, node, name, cluster, offset);
+       rc = rename_entry(ef, dir, node, name, cluster, offset);

        exfat_put_node(ef, dir);
        exfat_put_node(ef, node);
        return 0;
        exfat_put_node(ef, dir);
        exfat_put_node(ef, node);
        return 0;


@@ -837,3 +1114,76 @@ void exfat_update_mtime(struct exfat_node* node)
        node->mtime = time(NULL);
        node->flags |= EXFAT_ATTRIB_DIRTY;
 }
        node->mtime = time(NULL);
        node->flags |= EXFAT_ATTRIB_DIRTY;
 }

+
+const char* exfat_get_label(struct exfat* ef)
+{
+       return ef->label;
+}
+
+static int find_label(struct exfat* ef, cluster_t* cluster, off_t* offset)
+{
+       struct iterator it;
+       int rc;
+
+       rc = opendir(ef, ef->root, &it);
+       if (rc != 0)
+               return rc;
+
+       for (;;)
+       {
+               if (it.offset >= ef->root->size)
+               {
+                       closedir(&it);
+                       return -ENOENT;
+               }
+
+               if (get_entry_ptr(ef, &it)->type == EXFAT_ENTRY_LABEL)
+               {
+                       *cluster = it.cluster;
+                       *offset = it.offset;
+                       closedir(&it);
+                       return 0;
+               }
+
+               if (fetch_next_entry(ef, ef->root, &it) != 0)
+               {
+                       closedir(&it);
+                       return -EIO;
+               }
+       }
+}
+
+int exfat_set_label(struct exfat* ef, const char* label)
+{
+       le16_t label_utf16[EXFAT_ENAME_MAX + 1];
+       int rc;
+       cluster_t cluster;
+       off_t offset;
+       struct exfat_entry_label entry;
+
+       memset(label_utf16, 0, sizeof(label_utf16));
+       rc = utf8_to_utf16(label_utf16, label, EXFAT_ENAME_MAX, strlen(label));
+       if (rc != 0)
+               return rc;
+
+       rc = find_label(ef, &cluster, &offset);
+       if (rc == -ENOENT)
+               rc = find_slot(ef, ef->root, &cluster, &offset, 1);
+       if (rc != 0)
+               return rc;
+
+       entry.type = EXFAT_ENTRY_LABEL;
+       entry.length = utf16_length(label_utf16);
+       memcpy(entry.name, label_utf16, sizeof(entry.name));
+       if (entry.length == 0)
+               entry.type ^= EXFAT_ENTRY_VALID;
+
+       if (exfat_pwrite(ef->dev, &entry, sizeof(struct exfat_entry_label),
+                       co2o(ef, cluster, offset)) < 0)
+       {
+               exfat_error("failed to write label entry");
+               return -EIO;
+       }
+       strcpy(ef->label, label);
+       return 0;
+}