return 0;
}
+/* Returns nonzero if write permission is requested on the file open flags */
static inline int flags_writable(int open_flags)
{
return open_flags & (O_RDWR | O_WRONLY);
}
+/*
+ * Allocate a file descriptor for a lookup table entry
+ */
static int alloc_wimlib_fd(struct lookup_table_entry *lte,
struct wimlib_fd **fd_ret)
{
return -EMFILE;
num_new_fds = min(fds_per_alloc, max_fds - lte->num_allocated_fds);
- fds = CALLOC(lte->num_allocated_fds + num_new_fds,
- sizeof(lte->fds[0]));
+ fds = REALLOC(lte->fds, (lte->num_allocated_fds + num_new_fds) *
+ sizeof(lte->fds[0]));
if (!fds)
return -ENOMEM;
- memcpy(fds, lte->fds,
- lte->num_allocated_fds * sizeof(lte->fds[0]));
- FREE(lte->fds);
+ memset(&fds[lte->num_allocated_fds], 0,
+ num_new_fds * sizeof(fds[0]));
lte->fds = fds;
lte->num_allocated_fds += num_new_fds;
}
unlink(lte->staging_file_name);
free_lookup_table_entry(lte);
}
+ wimlib_assert(lte->fds[fd->idx] == fd);
lte->fds[fd->idx] = NULL;
FREE(fd);
return 0;
}
+/* Remove a dentry and all its alternate file streams */
static void remove_dentry(struct dentry *dentry,
struct lookup_table *lookup_table)
{
- const u8 *hash = dentry->hash;
+ wimlib_assert(dentry);
+ wimlib_assert(dentry->resolved);
+
+ struct lookup_table_entry *lte = dentry->lte;
u16 i = 0;
- struct lookup_table_entry *lte;
while (1) {
- lte = lookup_table_decrement_refcnt(lookup_table, hash);
+ lte = lte_decrement_refcnt(lte, lookup_table);
if (lte && lte->num_opened_fds)
for (u16 i = 0; i < lte->num_allocated_fds; i++)
if (lte->fds[i] && lte->fds[i]->dentry == dentry)
lte->fds[i]->dentry = NULL;
if (i == dentry->num_ads)
break;
- hash = dentry->ads_entries[i].hash;
+ lte = dentry->ads_entries[i].lte;
i++;
}
return fd;
}
-/* Removes open file descriptors from a lookup table entry @old_lte where the
+/*
+ * Removes open file descriptors from a lookup table entry @old_lte where the
* file descriptors have opened the corresponding file resource in the context
* of the hard link group @link_group; these file descriptors are extracted and
- * placed in a new lookup table entry, which is returned. */
+ * placed in a new lookup table entry, which is returned.
+ */
static struct lookup_table_entry *
lte_extract_fds(struct lookup_table_entry *old_lte, u64 link_group)
{
num_transferred_fds = 0;
for (u16 i = 0; i < old_lte->num_allocated_fds; i++)
- if (old_lte->fds[i] &&
+ if (old_lte->fds[i] && old_lte->fds[i]->dentry &&
old_lte->fds[i]->dentry->hard_link == link_group)
num_transferred_fds++;
DEBUG("Transferring %u file descriptors",
return NULL;
}
for (u16 i = 0, j = 0; ; i++) {
- if (old_lte->fds[i] &&
+ if (old_lte->fds[i] && old_lte->fds[i]->dentry &&
old_lte->fds[i]->dentry->hard_link == link_group) {
struct wimlib_fd *fd = old_lte->fds[i];
old_lte->fds[i] = NULL;
static void lte_transfer_dentry(struct lookup_table_entry *new_lte,
struct dentry *dentry)
{
+ wimlib_assert(dentry->lte_group_list.list.next);
+ wimlib_assert(new_lte->lte_group_list.next);
list_del(&dentry->lte_group_list.list);
list_add(&dentry->lte_group_list.list, &new_lte->lte_group_list);
dentry->lte = new_lte;
struct dentry *dentry,
unsigned stream_idx)
{
- /*INIT_LIST_HEAD(&new_lte->lte_group_list);*/
+ INIT_LIST_HEAD(&new_lte->lte_group_list);
if (stream_idx == 0) {
struct list_head *pos = &dentry->link_group_list;
do {
struct dentry *d;
d = container_of(pos, struct dentry, link_group_list);
+ wimlib_assert(d->hard_link == dentry->hard_link);
lte_transfer_dentry(new_lte, d);
-
pos = pos->next;
} while (pos != &dentry->link_group_list);
} else {
struct ads_entry *ads_entry;
+ wimlib_assert(stream_idx <= dentry->num_ads);
ads_entry = &dentry->ads_entries[stream_idx - 1];
lte_transfer_ads_entry(new_lte, ads_entry);
}
/*
* Extract a WIM resource to the staging directory.
*
- * We need to:
- * - Create a staging file for the WIM resource
- * - Extract the resource to it
- * - Create a new lte for the file resource
- * - Transfer fds from the old lte to the new lte, but
- * only if they share the same hard link group as this
- * dentry
- * - Transfer stream entries from the old lte's list to the new lte's list.
+ * @dentry, @stream_idx: The stream on whose behalf we are modifying the lookup
+ * table entry (these may be more streams than this that reference the lookup
+ * table entry)
*
- * *lte is permitted to be NULL, in which case there is no old lookup table
- * entry.
+ * @lte: Pointer to pointer to the lookup table entry for the stream we need to
+ * extract, or NULL if there was no lookup table entry present for the stream
+ *
+ * @size: Number of bytes of the stream we want to extract (this supports the
+ * wimfs_truncate() function).
*/
static int extract_resource_to_staging_dir(struct dentry *dentry,
unsigned stream_idx,
struct lookup_table_entry *old_lte, *new_lte;
size_t link_group_size;
+ /*
+ * We need to:
+ * - Create a staging file for the WIM resource
+ * - Extract the resource to it
+ * - Create a new lte for the file resource
+ * - Transfer fds from the old lte to the new lte, but only if they share the
+ * same hard link group as this dentry. If there is no old lte, then this
+ * step does not need to be done
+ * - Transfer stream entries from the old lte's list to the new lte's list. If
+ * there is no old lte, we instead transfer entries for the hard link group.
+ *
+ * Note: *lte is permitted to be NULL, in which case there is no old
+ * lookup table entry.
+ */
+
DEBUG("Extracting resource `%s' to staging directory", dentry->full_path_utf8);
old_lte = *lte;
* groups that were identical, but now we are changing
* one of them) */
- /* XXX The ADS really complicate things here and not
+ /* XXX
+ * The ADS really complicate things here and not
* everything is going to work correctly yet. For
* example it could be the same that a file contains two
* file streams that are identical and therefore share
* the same lookup table entry despite the fact that the
- * streams themselves are not hardlinked. */
+ * streams themselves are not hardlinked.
+ * XXX*/
wimlib_assert(old_lte->refcnt > link_group_size);
new_lte = lte_extract_fds(old_lte, dentry->hard_link);
}
/* The ADS entries are owned by another dentry. */
- from_dentry->link_group_master_status = GROUP_SLAVE;
+ from_dentry->ads_entries_status = ADS_ENTRIES_USER;
link_dentry(from_dentry, from_dentry_parent);
return 0;
newdir = new_dentry(basename);
newdir->attributes |= FILE_ATTRIBUTE_DIRECTORY;
newdir->resolved = true;
+ newdir->hard_link = next_link_group_id++;
link_dentry(newdir, parent);
return 0;
}
return 0;
}
+ wimlib_assert(fd->lte);
+
if (fd->lte->staging_file_name) {
/* Read from staging file */
return -errno;
return ret;
} else {
-
/* Read from WIM */
struct resource_entry *res_entry;
/* Fills in the entries of the directory specified by @path using the
* FUSE-provided function @filler. */
static int wimfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
- off_t offset, struct fuse_file_info *fi)
+ off_t offset, struct fuse_file_info *fi)
{
struct dentry *parent, *child;
parent = (struct dentry*)fi->fh;
+ wimlib_assert(parent);
child = parent->children;
filler(buf, ".", NULL, 0);
{
struct dentry *dentry = (struct dentry *)fi->fh;
+ wimlib_assert(dentry);
wimlib_assert(dentry->num_times_opened);
if (--dentry->num_times_opened == 0)
free_dentry(dentry);
return -ENOMEM;
if (dst) {
+ /* Destination file exists */
+
if (src == dst) /* Same file */
return 0;
parent_of_dst = dst->parent;
remove_dentry(dst, w->lookup_table);
} else {
+ /* Destination does not exist */
parent_of_dst = get_parent_dentry(w, to);
if (!parent_of_dst)
return -ENOENT;
+
+ if (!dentry_is_directory(parent_of_dst))
+ return -ENOTDIR;
}
FREE(src->file_name);
dentry->attributes = FILE_ATTRIBUTE_REPARSE_POINT;
dentry->reparse_tag = WIM_IO_REPARSE_TAG_SYMLINK;
+ dentry->hard_link = next_link_group_id++;
if (dentry_set_symlink(dentry, to, w->lookup_table, <e) != 0)
goto out_free_dentry;
+ wimlib_assert(lte);
+
dentry->ads_entries[1].lte_group_list.type = STREAM_TYPE_ADS;
list_add(&dentry->ads_entries[1].lte_group_list.list,
<e->lte_group_list);
struct ads_entry *ads_entry;
ads_entry = &dentry->ads_entries[stream_idx - 1];
- lte_decrement_refcnt(lte, w->lookup_table);
- list_del(&ads_entry->lte_group_list.list);
+ lte = lte_decrement_refcnt(lte, w->lookup_table);
+ if (lte)
+ list_del(&ads_entry->lte_group_list.list);
dentry_remove_ads(dentry, ads_entry);
}
/* Beware: The lookup table entry(s) may still be referenced by users
return ret;
}
-
static struct fuse_operations wimfs_operations = {
.access = wimfs_access,
.destroy = wimfs_destroy,
};
+static int check_lte_refcnt(struct lookup_table_entry *lte, void *ignore)
+{
+ size_t lte_group_size = 0;
+ struct list_head *cur;
+ list_for_each(cur, <e->lte_group_list)
+ lte_group_size++;
+ if (lte_group_size > lte->refcnt) {
+#ifdef ENABLE_ERROR_MESSAGES
+ ERROR("The following lookup table entry has a reference count "
+ "of %u, but", lte->refcnt);
+ ERROR("We found %u references to it", lte_group_size);
+ print_lookup_table_entry(lte, NULL);
+#endif
+ return WIMLIB_ERR_INVALID_DENTRY;
+ }
+ return 0;
+}
+
/* Mounts a WIM file. */
WIMLIBAPI int wimlib_mount(WIMStruct *wim, int image, const char *dir,
int flags)
next_link_group_id = assign_link_groups(wim->image_metadata[image - 1].lgt);
- resolve_lookup_table_entries(wim_root_dentry(wim), wim->lookup_table);
+ /* Resolve all the lookup table entries of the dentry tree */
+ for_dentry_in_tree(wim_root_dentry(wim), dentry_resolve_ltes,
+ wim->lookup_table);
+
+ ret = for_lookup_table_entry(wim->lookup_table, check_lte_refcnt, NULL);
+ if (ret != 0)
+ return ret;
if (flags & WIMLIB_MOUNT_FLAG_READWRITE)
wim_get_current_image_metadata(wim)->modified = true;
argv[argc++] = p;
argv[argc++] = "-s"; /* disable multi-threaded operation */
- if (flags & WIMLIB_MOUNT_FLAG_DEBUG) {
+ if (flags & WIMLIB_MOUNT_FLAG_DEBUG)
argv[argc++] = "-d";
- }
+
+ /*
+ * We provide the use_ino option because we are going to assign inode
+ * numbers oursides. We've already numbered the hard link groups with
+ * unique numbers with the assign_link_groups() function, and the static
+ * variable next_link_group_id is set to the next available link group
+ * ID that we will assign to new dentries.
+ */
char optstring[256] = "use_ino";
argv[argc++] = "-o";
argv[argc++] = optstring;
if ((flags & WIMLIB_MOUNT_FLAG_READWRITE)) {
+ /* Read-write mount. Make the staging directory */
make_staging_dir();
if (!staging_dir_name) {
FREE(p);
return WIMLIB_ERR_MKDIR;
}
} else {
+ /* Read-only mount */
strcat(optstring, ",ro");
}
argv[argc] = NULL;
* filesystem daemon has crashed or failed for some reason.
*
* XXX come up with some method to determine if the filesystem
- * daemon has really crashed or not. */
+ * daemon has really crashed or not.
+ *
+ * XXX Idea: have mount daemon write its PID into the WIM file header?
+ * */
gettimeofday(&now, NULL);
timeout.tv_sec = now.tv_sec + 600;
git://wimlib.net / wimlib / blobdiff