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-rw-r--r--exfat/node.c1038
1 files changed, 1038 insertions, 0 deletions
diff --git a/exfat/node.c b/exfat/node.c
new file mode 100644
index 000000000..d5104038e
--- /dev/null
+++ b/exfat/node.c
@@ -0,0 +1,1038 @@
+/*
+ node.c (09.10.09)
+ exFAT file system implementation library.
+
+ Copyright (C) 2010-2012 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 <http://www.gnu.org/licenses/>.
+*/
+
+#include "exfat.h"
+#include <errno.h>
+#include <string.h>
+#include <inttypes.h>
+
+/* on-disk nodes iterator */
+struct iterator
+{
+ cluster_t cluster;
+ off64_t offset;
+ int contiguous;
+ char* chunk;
+};
+
+struct exfat_node* exfat_get_node(struct exfat_node* node)
+{
+ /* if we switch to multi-threaded mode we will need atomic
+ increment here and atomic decrement in exfat_put_node() */
+ node->references++;
+ return node;
+}
+
+void exfat_put_node(struct exfat* ef, struct exfat_node* node)
+{
+ if (--node->references < 0)
+ {
+ char buffer[EXFAT_NAME_MAX + 1];
+ exfat_get_name(node, buffer, EXFAT_NAME_MAX);
+ 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);
+ if (node->flags & EXFAT_ATTRIB_UNLINKED)
+ {
+ /* free all clusters and node structure itself */
+ exfat_truncate(ef, node, 0);
+ free(node);
+ }
+ if (ef->cmap.dirty)
+ exfat_flush_cmap(ef);
+ }
+}
+
+/**
+ * Cluster + offset from the beginning of the directory to absolute offset.
+ */
+static off64_t co2o(struct exfat* ef, cluster_t cluster, off64_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)
+{
+ if (!(dir->flags & EXFAT_ATTRIB_DIR))
+ exfat_bug("not a directory");
+ it->cluster = dir->start_cluster;
+ it->offset = 0;
+ it->contiguous = IS_CONTIGUOUS(*dir);
+ it->chunk = malloc(CLUSTER_SIZE(*ef->sb));
+ if (it->chunk == NULL)
+ {
+ exfat_error("out of memory");
+ return -ENOMEM;
+ }
+ exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+ exfat_c2o(ef, it->cluster));
+ return 0;
+}
+
+static void closedir(struct iterator* it)
+{
+ it->cluster = 0;
+ it->offset = 0;
+ it->contiguous = 0;
+ free(it->chunk);
+ it->chunk = NULL;
+}
+
+static int fetch_next_entry(struct exfat* ef, const struct exfat_node* parent,
+ struct iterator* it)
+{
+ /* move iterator to the next entry in the directory */
+ it->offset += sizeof(struct exfat_entry);
+ /* 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))
+ {
+ exfat_error("invalid cluster 0x%x while reading directory",
+ it->cluster);
+ return 1;
+ }
+ exfat_pread(ef->dev, it->chunk, CLUSTER_SIZE(*ef->sb),
+ exfat_c2o(ef, it->cluster));
+ }
+ return 0;
+}
+
+static struct exfat_node* allocate_node(void)
+{
+ struct exfat_node* node = malloc(sizeof(struct exfat_node));
+ if (node == NULL)
+ {
+ exfat_error("failed to allocate node");
+ return NULL;
+ }
+ memset(node, 0, sizeof(struct exfat_node));
+ return node;
+}
+
+static void init_node_meta1(struct exfat_node* node,
+ const struct exfat_entry_meta1* meta1)
+{
+ node->flags = le16_to_cpu(meta1->attrib);
+ 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,
+ const struct exfat_entry_meta2* meta2)
+{
+ node->size = le64_to_cpu(meta2->size);
+ node->start_cluster = le32_to_cpu(meta2->start_cluster);
+ node->fptr_cluster = node->start_cluster;
+ if (meta2->flags & EXFAT_FLAG_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));
+}
+
+/*
+ * Reads one entry in directory at position pointed by iterator and fills
+ * node structure.
+ */
+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_name* file_name;
+ const struct exfat_entry_upcase* upcase;
+ const struct exfat_entry_bitmap* bitmap;
+ const struct exfat_entry_label* label;
+ uint8_t continuations = 0;
+ le16_t* namep = NULL;
+ uint16_t reference_checksum = 0;
+ uint16_t actual_checksum = 0;
+ uint64_t real_size = 0;
+
+ *node = NULL;
+
+ for (;;)
+ {
+ if (it->offset >= parent->size)
+ {
+ if (continuations != 0)
+ {
+ exfat_error("expected %hhu continuations", continuations);
+ 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)
+ {
+ exfat_error("expected %hhu continuations before new entry",
+ continuations);
+ goto error;
+ }
+ meta1 = (const struct exfat_entry_meta1*) entry;
+ continuations = meta1->continuations;
+ /* each file entry must have at least 2 continuations:
+ info and name */
+ if (continuations < 2)
+ {
+ exfat_error("too few continuations (%hhu)", continuations);
+ goto error;
+ }
+ reference_checksum = le16_to_cpu(meta1->checksum);
+ actual_checksum = exfat_start_checksum(meta1);
+ *node = allocate_node();
+ if (*node == NULL)
+ {
+ rc = -ENOMEM;
+ goto error;
+ }
+ /* new node has zero reference counter */
+ (*node)->entry_cluster = it->cluster;
+ (*node)->entry_offset = it->offset;
+ init_node_meta1(*node, meta1);
+ namep = (*node)->name;
+ break;
+
+ case EXFAT_ENTRY_FILE_INFO:
+ if (continuations < 2)
+ {
+ exfat_error("unexpected continuation (%hhu)",
+ continuations);
+ 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);
+ 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("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)
+ {
+ exfat_error("directory has invalid size %"PRIu64" bytes",
+ (*node)->size);
+ goto error;
+ }
+ --continuations;
+ break;
+
+ case EXFAT_ENTRY_FILE_NAME:
+ if (continuations == 0)
+ {
+ exfat_error("unexpected continuation");
+ goto error;
+ }
+ 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));
+ namep += EXFAT_ENAME_MAX;
+ if (--continuations == 0)
+ {
+ /*
+ 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.
+
+ There is an exception though: pagefile.sys (its real_size
+ is always 0).
+ */
+ if (real_size != (*node)->size)
+ {
+ char buffer[EXFAT_NAME_MAX + 1];
+
+ exfat_get_name(*node, buffer, EXFAT_NAME_MAX);
+ exfat_error("`%s' real size does not equal to size "
+ "(%"PRIu64" != %"PRIu64")", buffer,
+ real_size, (*node)->size);
+ goto error;
+ }
+ if (actual_checksum != reference_checksum)
+ {
+ char buffer[EXFAT_NAME_MAX + 1];
+
+ exfat_get_name(*node, buffer, EXFAT_NAME_MAX);
+ exfat_error("`%s' has invalid checksum (0x%hx != 0x%hx)",
+ buffer, actual_checksum, reference_checksum);
+ goto error;
+ }
+ if (fetch_next_entry(ef, parent, it) != 0)
+ goto error;
+ return 0; /* entry completed */
+ }
+ break;
+
+ case EXFAT_ENTRY_UPCASE:
+ if (ef->upcase != NULL)
+ break;
+ upcase = (const struct exfat_entry_upcase*) entry;
+ if (CLUSTER_INVALID(le32_to_cpu(upcase->start_cluster)))
+ {
+ 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) ||
+ le64_to_cpu(upcase->size) % sizeof(uint16_t) != 0)
+ {
+ exfat_error("bad upcase table size (%"PRIu64" bytes)",
+ le64_to_cpu(upcase->size));
+ 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));
+ rc = -ENOMEM;
+ goto error;
+ }
+ ef->upcase_chars = le64_to_cpu(upcase->size) / sizeof(le16_t);
+
+ exfat_pread(ef->dev, ef->upcase, le64_to_cpu(upcase->size),
+ exfat_c2o(ef, le32_to_cpu(upcase->start_cluster)));
+ break;
+
+ case EXFAT_ENTRY_BITMAP:
+ bitmap = (const struct exfat_entry_bitmap*) entry;
+ ef->cmap.start_cluster = le32_to_cpu(bitmap->start_cluster);
+ if (CLUSTER_INVALID(ef->cmap.start_cluster))
+ {
+ 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;
+ if (le64_to_cpu(bitmap->size) < (ef->cmap.size + 7) / 8)
+ {
+ exfat_error("invalid clusters bitmap size: %"PRIu64
+ " (expected at least %u)",
+ le64_to_cpu(bitmap->size), (ef->cmap.size + 7) / 8);
+ goto error;
+ }
+ /* 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));
+ if (ef->cmap.chunk == NULL)
+ {
+ exfat_error("failed to allocate clusters bitmap chunk "
+ "(%"PRIu64" bytes)", le64_to_cpu(bitmap->size));
+ rc = -ENOMEM;
+ goto error;
+ }
+
+ exfat_pread(ef->dev, ef->cmap.chunk, le64_to_cpu(bitmap->size),
+ exfat_c2o(ef, ef->cmap.start_cluster));
+ break;
+
+ case EXFAT_ENTRY_LABEL:
+ label = (const struct exfat_entry_label*) entry;
+ if (label->length > EXFAT_ENAME_MAX)
+ {
+ exfat_error("too long label (%hhu chars)", label->length);
+ goto error;
+ }
+ if (utf16_to_utf8(ef->label, label->name,
+ sizeof(ef->label), EXFAT_ENAME_MAX) != 0)
+ goto error;
+ break;
+
+ default:
+ if (entry->type & EXFAT_ENTRY_VALID)
+ {
+ exfat_error("unknown entry type 0x%hhx", entry->type);
+ goto error;
+ }
+ break;
+ }
+
+ if (fetch_next_entry(ef, parent, it) != 0)
+ goto error;
+ }
+ /* we never reach here */
+
+error:
+ free(*node);
+ *node = NULL;
+ return rc;
+}
+
+int exfat_cache_directory(struct exfat* ef, struct exfat_node* dir)
+{
+ struct iterator it;
+ int rc;
+ struct exfat_node* node;
+ struct exfat_node* current = NULL;
+
+ if (dir->flags & EXFAT_ATTRIB_CACHED)
+ return 0; /* already cached */
+
+ rc = opendir(ef, dir, &it);
+ if (rc != 0)
+ return rc;
+ while ((rc = readdir(ef, dir, &node, &it)) == 0)
+ {
+ node->parent = dir;
+ if (current != NULL)
+ {
+ current->next = node;
+ node->prev = current;
+ }
+ else
+ dir->child = node;
+
+ current = node;
+ }
+ closedir(&it);
+
+ if (rc != -ENOENT)
+ {
+ /* rollback */
+ for (current = dir->child; current; current = node)
+ {
+ node = current->next;
+ free(current);
+ }
+ dir->child = NULL;
+ return rc;
+ }
+
+ dir->flags |= EXFAT_ATTRIB_CACHED;
+ return 0;
+}
+
+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)
+{
+ 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;
+}
+
+static void reset_cache(struct exfat* ef, struct exfat_node* node)
+{
+ while (node->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)
+ {
+ char buffer[EXFAT_NAME_MAX + 1];
+ exfat_get_name(node, buffer, EXFAT_NAME_MAX);
+ exfat_warn("non-zero reference counter (%d) for `%s'",
+ node->references, buffer);
+ }
+ while (node->references)
+ exfat_put_node(ef, node);
+}
+
+void exfat_reset_cache(struct exfat* ef)
+{
+ reset_cache(ef, ef->root);
+}
+
+void next_entry(struct exfat* ef, const struct exfat_node* parent,
+ cluster_t* cluster, off64_t* offset)
+{
+ *offset += sizeof(struct exfat_entry);
+ if (*offset % CLUSTER_SIZE(*ef->sb) == 0)
+ /* next cluster cannot be invalid */
+ *cluster = exfat_next_cluster(ef, parent, *cluster);
+}
+
+void exfat_flush_node(struct exfat* ef, struct exfat_node* node)
+{
+ cluster_t cluster;
+ off64_t offset;
+ off64_t meta1_offset, meta2_offset;
+ struct exfat_entry_meta1 meta1;
+ struct exfat_entry_meta2 meta2;
+
+ if (ef->ro)
+ exfat_bug("unable to flush node to read-only FS");
+
+ if (node->parent == NULL)
+ return; /* do not flush unlinked node */
+
+ cluster = node->entry_cluster;
+ offset = node->entry_offset;
+ meta1_offset = co2o(ef, cluster, offset);
+ next_entry(ef, node->parent, &cluster, &offset);
+ meta2_offset = co2o(ef, cluster, offset);
+
+ exfat_pread(ef->dev, &meta1, sizeof(meta1), meta1_offset);
+ 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, &meta1.mtime_cs);
+ exfat_unix2exfat(node->atime, &meta1.adate, &meta1.atime, NULL);
+
+ exfat_pread(ef->dev, &meta2, sizeof(meta2), meta2_offset);
+ 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);
+ meta2.flags = EXFAT_FLAG_ALWAYS1;
+ /* empty files must not be marked as contiguous */
+ if (node->size != 0 && IS_CONTIGUOUS(*node))
+ meta2.flags |= EXFAT_FLAG_CONTIGUOUS;
+ /* name hash remains unchanged, no need to recalculate it */
+
+ meta1.checksum = exfat_calc_checksum(&meta1, &meta2, node->name);
+
+ exfat_pwrite(ef->dev, &meta1, sizeof(meta1), meta1_offset);
+ exfat_pwrite(ef->dev, &meta2, sizeof(meta2), meta2_offset);
+
+ node->flags &= ~EXFAT_ATTRIB_DIRTY;
+}
+
+static void erase_entry(struct exfat* ef, struct exfat_node* node)
+{
+ cluster_t cluster = node->entry_cluster;
+ off64_t offset = node->entry_offset;
+ int name_entries = DIV_ROUND_UP(utf16_length(node->name), EXFAT_ENAME_MAX);
+ uint8_t entry_type;
+
+ entry_type = EXFAT_ENTRY_FILE & ~EXFAT_ENTRY_VALID;
+ exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset));
+
+ next_entry(ef, node->parent, &cluster, &offset);
+ entry_type = EXFAT_ENTRY_FILE_INFO & ~EXFAT_ENTRY_VALID;
+ exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset));
+
+ while (name_entries--)
+ {
+ next_entry(ef, node->parent, &cluster, &offset);
+ entry_type = EXFAT_ENTRY_FILE_NAME & ~EXFAT_ENTRY_VALID;
+ exfat_pwrite(ef->dev, &entry_type, 1, co2o(ef, cluster, offset));
+ }
+}
+
+static int shrink_directory(struct exfat* ef, struct exfat_node* dir,
+ off64_t deleted_offset)
+{
+ const struct exfat_node* node;
+ const struct exfat_node* last_node;
+ uint64_t entries = 0;
+ uint64_t new_size;
+ int rc;
+
+ 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)
+ {
+ 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;
+ }
+
+ 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;
+ rc = exfat_truncate(ef, dir, new_size);
+ if (rc != 0)
+ return rc;
+ return 0;
+}
+
+static int delete(struct exfat* ef, struct exfat_node* node)
+{
+ struct exfat_node* parent = node->parent;
+ off64_t deleted_offset = node->entry_offset;
+ int rc;
+
+ exfat_get_node(parent);
+ erase_entry(ef, node);
+ exfat_update_mtime(parent);
+ 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;
+ return rc;
+}
+
+int exfat_unlink(struct exfat* ef, struct exfat_node* node)
+{
+ if (node->flags & EXFAT_ATTRIB_DIR)
+ return -EISDIR;
+ return delete(ef, node);
+}
+
+int exfat_rmdir(struct exfat* ef, struct exfat_node* node)
+{
+ if (!(node->flags & EXFAT_ATTRIB_DIR))
+ return -ENOTDIR;
+ /* check that directory is empty */
+ exfat_cache_directory(ef, node);
+ if (node->child)
+ return -ENOTEMPTY;
+ return delete(ef, node);
+}
+
+static int grow_directory(struct exfat* ef, struct exfat_node* dir,
+ uint64_t asize, uint32_t difference)
+{
+ return exfat_truncate(ef, dir,
+ DIV_ROUND_UP(asize + difference, CLUSTER_SIZE(*ef->sb))
+ * CLUSTER_SIZE(*ef->sb));
+}
+
+static int find_slot(struct exfat* ef, struct exfat_node* dir,
+ cluster_t* cluster, off64_t* offset, int subentries)
+{
+ struct iterator it;
+ int rc;
+ const struct exfat_entry* entry;
+ int contiguous = 0;
+
+ rc = opendir(ef, dir, &it);
+ if (rc != 0)
+ return rc;
+ for (;;)
+ {
+ if (contiguous == 0)
+ {
+ *cluster = it.cluster;
+ *offset = it.offset;
+ }
+ 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, dir->size,
+ (subentries - contiguous) * sizeof(struct exfat_entry));
+ if (rc != 0)
+ {
+ closedir(&it);
+ return rc;
+ }
+ }
+ if (fetch_next_entry(ef, dir, &it) != 0)
+ {
+ closedir(&it);
+ return -EIO;
+ }
+ }
+ closedir(&it);
+ return 0;
+}
+
+static int write_entry(struct exfat* ef, struct exfat_node* dir,
+ const le16_t* name, cluster_t cluster, off64_t offset, uint16_t attrib)
+{
+ struct exfat_node* node;
+ struct exfat_entry_meta1 meta1;
+ struct exfat_entry_meta2 meta2;
+ const size_t name_length = utf16_length(name);
+ const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
+ int i;
+
+ node = allocate_node();
+ if (node == NULL)
+ return -ENOMEM;
+ node->entry_cluster = cluster;
+ node->entry_offset = offset;
+ memcpy(node->name, name, name_length * sizeof(le16_t));
+
+ memset(&meta1, 0, sizeof(meta1));
+ meta1.type = EXFAT_ENTRY_FILE;
+ meta1.continuations = 1 + name_entries;
+ meta1.attrib = cpu_to_le16(attrib);
+ exfat_unix2exfat(time(NULL), &meta1.crdate, &meta1.crtime,
+ &meta1.crtime_cs);
+ meta1.adate = meta1.mdate = meta1.crdate;
+ meta1.atime = meta1.mtime = meta1.crtime;
+ meta1.mtime_cs = meta1.crtime_cs; /* there is no atime_cs */
+
+ memset(&meta2, 0, sizeof(meta2));
+ meta2.type = EXFAT_ENTRY_FILE_INFO;
+ 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);
+
+ exfat_pwrite(ef->dev, &meta1, sizeof(meta1), co2o(ef, cluster, offset));
+ next_entry(ef, dir, &cluster, &offset);
+ exfat_pwrite(ef->dev, &meta2, sizeof(meta2), co2o(ef, cluster, offset));
+ 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_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+ co2o(ef, cluster, offset));
+ }
+
+ init_node_meta1(node, &meta1);
+ init_node_meta2(node, &meta2);
+
+ tree_attach(dir, node);
+ exfat_update_mtime(dir);
+ return 0;
+}
+
+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;
+ off64_t offset = -1;
+ le16_t name[EXFAT_NAME_MAX + 1];
+ int rc;
+
+ rc = exfat_split(ef, &dir, &existing, name, path);
+ 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));
+ if (rc != 0)
+ {
+ exfat_put_node(ef, dir);
+ return rc;
+ }
+ rc = write_entry(ef, dir, name, cluster, offset, attrib);
+ exfat_put_node(ef, dir);
+ return rc;
+}
+
+int exfat_mknod(struct exfat* ef, const char* path)
+{
+ return create(ef, path, EXFAT_ATTRIB_ARCH);
+}
+
+int exfat_mkdir(struct exfat* ef, const char* path)
+{
+ int rc;
+ struct exfat_node* node;
+
+ rc = create(ef, path, EXFAT_ATTRIB_ARCH | EXFAT_ATTRIB_DIR);
+ if (rc != 0)
+ return rc;
+ rc = exfat_lookup(ef, &node, path);
+ if (rc != 0)
+ return 0;
+ /* directories always have at least one cluster */
+ rc = exfat_truncate(ef, node, CLUSTER_SIZE(*ef->sb));
+ if (rc != 0)
+ {
+ delete(ef, node);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ exfat_put_node(ef, node);
+ return 0;
+}
+
+static void rename_entry(struct exfat* ef, struct exfat_node* dir,
+ struct exfat_node* node, const le16_t* name, cluster_t new_cluster,
+ off64_t new_offset)
+{
+ struct exfat_entry_meta1 meta1;
+ struct exfat_entry_meta2 meta2;
+ cluster_t old_cluster = node->entry_cluster;
+ off64_t old_offset = node->entry_offset;
+ const size_t name_length = utf16_length(name);
+ const int name_entries = DIV_ROUND_UP(name_length, EXFAT_ENAME_MAX);
+ int i;
+
+ exfat_pread(ef->dev, &meta1, sizeof(meta1),
+ co2o(ef, old_cluster, old_offset));
+ next_entry(ef, node->parent, &old_cluster, &old_offset);
+ exfat_pread(ef->dev, &meta2, sizeof(meta2),
+ co2o(ef, old_cluster, old_offset));
+ 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);
+
+ node->entry_cluster = new_cluster;
+ node->entry_offset = new_offset;
+
+ exfat_pwrite(ef->dev, &meta1, sizeof(meta1),
+ co2o(ef, new_cluster, new_offset));
+ next_entry(ef, dir, &new_cluster, &new_offset);
+ exfat_pwrite(ef->dev, &meta2, sizeof(meta2),
+ co2o(ef, new_cluster, new_offset));
+
+ 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_pwrite(ef->dev, &name_entry, sizeof(name_entry),
+ co2o(ef, new_cluster, new_offset));
+ }
+
+ memcpy(node->name, name, (EXFAT_NAME_MAX + 1) * sizeof(le16_t));
+ tree_detach(node);
+ tree_attach(dir, 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;
+ off64_t offset = -1;
+ le16_t name[EXFAT_NAME_MAX + 1];
+ int rc;
+
+ rc = exfat_lookup(ef, &node, old_path);
+ if (rc != 0)
+ return rc;
+
+ rc = exfat_split(ef, &dir, &existing, name, new_path);
+ if (rc != 0)
+ {
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ 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)
+ {
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return rc;
+ }
+ rename_entry(ef, dir, node, name, cluster, offset);
+ exfat_put_node(ef, dir);
+ exfat_put_node(ef, node);
+ return 0;
+}
+
+void exfat_utimes(struct exfat_node* node, const struct timespec tv[2])
+{
+ node->atime = tv[0].tv_sec;
+ node->mtime = tv[1].tv_sec;
+ node->flags |= EXFAT_ATTRIB_DIRTY;
+}
+
+void exfat_update_atime(struct exfat_node* node)
+{
+ node->atime = time(NULL);
+ node->flags |= EXFAT_ATTRIB_DIRTY;
+}
+
+void exfat_update_mtime(struct exfat_node* node)
+{
+ 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, off64_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;
+ off64_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;
+
+ exfat_pwrite(ef->dev, &entry, sizeof(struct exfat_entry_label),
+ co2o(ef, cluster, offset));
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 05:16:28 +0100