struct wim_lookup_table_entry *lte, *existing_lte;
sha1_buffer(buffer, size, hash);
- existing_lte = __lookup_resource(lookup_table, hash);
+ existing_lte = lookup_resource(lookup_table, hash);
if (existing_lte) {
wimlib_assert(wim_resource_size(existing_lte) == size);
lte = existing_lte;
return for_image(wim, image, image_do_iterate_dir_tree);
}
+/* Returns %true iff the metadata of @inode and @template_inode are reasonably
+ * consistent with them being the same, unmodified file. */
static bool
-inode_stream_sizes_consistent(const struct wim_inode *inode_1,
- const struct wim_inode *inode_2,
- const struct wim_lookup_table *lookup_table)
+inode_metadata_consistent(const struct wim_inode *inode,
+ const struct wim_inode *template_inode,
+ const struct wim_lookup_table *template_lookup_table)
{
- if (inode_1->i_num_ads != inode_2->i_num_ads)
+ /* Must have exact same creation time and last write time. */
+ if (inode->i_creation_time != template_inode->i_creation_time ||
+ inode->i_last_write_time != template_inode->i_last_write_time)
return false;
- for (unsigned i = 0; i <= inode_1->i_num_ads; i++) {
- const struct wim_lookup_table_entry *lte_1, *lte_2;
- lte_1 = inode_stream_lte(inode_1, i, lookup_table);
- lte_2 = inode_stream_lte(inode_2, i, lookup_table);
- if (lte_1 && lte_2) {
- if (wim_resource_size(lte_1) != wim_resource_size(lte_2))
+ /* Last access time may have stayed the same or increased, but certainly
+ * shouldn't have decreased. */
+ if (inode->i_last_access_time < template_inode->i_last_access_time)
+ return false;
+
+ /* Must have same number of alternate data stream entries. */
+ if (inode->i_num_ads != template_inode->i_num_ads)
+ return false;
+
+ /* If the stream entries for the inode are for some reason not resolved,
+ * then the hashes are already available and the point of this function
+ * is defeated. */
+ if (!inode->i_resolved)
+ return false;
+
+ /* Iterate through each stream and do some more checks. */
+ for (unsigned i = 0; i <= inode->i_num_ads; i++) {
+ const struct wim_lookup_table_entry *lte, *template_lte;
+
+ lte = inode_stream_lte_resolved(inode, i);
+ template_lte = inode_stream_lte(template_inode, i,
+ template_lookup_table);
+
+ /* Compare stream sizes. */
+ if (lte && template_lte) {
+ if (wim_resource_size(lte) != wim_resource_size(template_lte))
return false;
- } else if (lte_1 && wim_resource_size(lte_1)) {
+
+ /* If hash happens to be available, compare with template. */
+ if (!lte->unhashed && !template_lte->unhashed &&
+ !hashes_equal(lte->hash, template_lte->hash))
+ return false;
+
+ } else if (lte && wim_resource_size(lte)) {
return false;
- } else if (lte_2 && wim_resource_size(lte_2)) {
+ } else if (template_lte && wim_resource_size(template_lte)) {
return false;
}
+
}
+
+ /* All right, barring a full checksum and given that the inodes share a
+ * path and the user isn't trying to trick us, these inodes most likely
+ * refer to the same file. */
return true;
}
-static void
-inode_replace_ltes(struct wim_inode *inode,
- struct wim_inode *template_inode,
- struct wim_lookup_table *lookup_table)
+/**
+ * Given an inode @inode that has been determined to be "the same" as another
+ * inode @template_inode in either the same WIM or another WIM, retrieve some
+ * useful stream information (e.g. checksums) from @template_inode.
+ *
+ * This assumes that the streams for @inode have been resolved (to point
+ * directly to the appropriate `struct wim_lookup_table_entry') but do not
+ * necessarily have checksum information filled in.
+ */
+static int
+inode_copy_checksums(struct wim_inode *inode,
+ struct wim_inode *template_inode,
+ WIMStruct *wim,
+ WIMStruct *template_wim)
{
for (unsigned i = 0; i <= inode->i_num_ads; i++) {
- struct wim_lookup_table_entry *lte, *lte_template;
+ struct wim_lookup_table_entry *lte, *template_lte;
+ struct wim_lookup_table_entry *replace_lte;
+
+ lte = inode_stream_lte_resolved(inode, i);
+ template_lte = inode_stream_lte(template_inode, i,
+ template_wim->lookup_table);
+
+ /* Only take action if both entries exist, the entry for @inode
+ * has no checksum calculated, but the entry for @template_inode
+ * does. */
+ if (!lte || !template_lte ||
+ !lte->unhashed || template_lte->unhashed)
+ continue;
- lte = inode_stream_lte(inode, i, lookup_table);
- if (lte) {
- for (unsigned j = 0; j < inode->i_nlink; j++)
- lte_decrement_refcnt(lte, lookup_table);
- lte_template = inode_stream_lte(template_inode, i,
- lookup_table);
- if (i == 0)
- inode->i_lte = lte_template;
- else
- inode->i_ads_entries[i - 1].lte = lte_template;
- if (lte_template)
- lte_template->refcnt += inode->i_nlink;
+ wimlib_assert(lte->refcnt == inode->i_nlink);
+
+ /* If the WIM of the template image is the same as the WIM of
+ * the new image, then @template_lte can be used directly.
+ *
+ * Otherwise, look for a stream with the same hash in the WIM of
+ * the new image. If found, use it; otherwise re-use the entry
+ * being discarded, filling in the hash. */
+
+ if (wim == template_wim)
+ replace_lte = template_lte;
+ else
+ replace_lte = lookup_resource(wim->lookup_table,
+ template_lte->hash);
+
+ list_del(<e->unhashed_list);
+ if (replace_lte) {
+ free_lookup_table_entry(lte);
+ } else {
+ copy_hash(lte->hash, template_lte->hash);
+ lte->unhashed = 0;
+ lookup_table_insert(wim->lookup_table, lte);
+ lte->refcnt = 0;
+ replace_lte = lte;
}
+
+ if (i == 0)
+ inode->i_lte = replace_lte;
+ else
+ inode->i_ads_entries[i - 1].lte = replace_lte;
+
+ replace_lte->refcnt += inode->i_nlink;
}
- inode->i_resolved = 1;
+ return 0;
}
+struct reference_template_args {
+ WIMStruct *wim;
+ WIMStruct *template_wim;
+};
+
static int
-dentry_reference_template(struct wim_dentry *dentry, void *_wim)
+dentry_reference_template(struct wim_dentry *dentry, void *_args)
{
int ret;
struct wim_dentry *template_dentry;
struct wim_inode *inode, *template_inode;
- WIMStruct *wim = _wim;
+ struct reference_template_args *args = _args;
+ WIMStruct *wim = args->wim;
+ WIMStruct *template_wim = args->template_wim;
if (dentry->d_inode->i_visited)
return 0;
if (ret)
return ret;
- template_dentry = get_dentry(wim, dentry->_full_path);
+ template_dentry = get_dentry(template_wim, dentry->_full_path);
if (!template_dentry) {
DEBUG("\"%"TS"\": newly added file", dentry->_full_path);
return 0;
inode = dentry->d_inode;
template_inode = template_dentry->d_inode;
- if (inode->i_last_write_time == template_inode->i_last_write_time
- && inode->i_creation_time == template_inode->i_creation_time
- && inode->i_last_access_time >= template_inode->i_last_access_time
- && inode_stream_sizes_consistent(inode, template_inode,
- wim->lookup_table))
- {
+ if (inode_metadata_consistent(inode, template_inode,
+ template_wim->lookup_table)) {
/*DEBUG("\"%"TS"\": No change detected", dentry->_full_path);*/
- inode_replace_ltes(inode, template_inode, wim->lookup_table);
+ ret = inode_copy_checksums(inode, template_inode,
+ wim, template_wim);
inode->i_visited = 1;
} else {
DEBUG("\"%"TS"\": change detected!", dentry->_full_path);
+ ret = 0;
}
- return 0;
+ return ret;
}
/* API function documented in wimlib.h */
WIMLIBAPI int
-wimlib_reference_template_image(WIMStruct *wim, int new_image, int template_image,
+wimlib_reference_template_image(WIMStruct *wim, int new_image,
+ WIMStruct *template_wim, int template_image,
int flags, wimlib_progress_func_t progress_func)
{
int ret;
struct wim_image_metadata *new_imd;
- if (new_image < 1 || new_image > wim->hdr.image_count)
- return WIMLIB_ERR_INVALID_IMAGE;
-
- if (template_image < 1 || template_image > wim->hdr.image_count)
- return WIMLIB_ERR_INVALID_IMAGE;
+ if (wim == NULL || template_wim == NULL)
+ return WIMLIB_ERR_INVALID_PARAM;
- if (new_image == template_image)
+ if (wim == template_wim && new_image == template_image)
return WIMLIB_ERR_INVALID_PARAM;
+ if (new_image < 1 || new_image > wim->hdr.image_count)
+ return WIMLIB_ERR_INVALID_IMAGE;
+
if (!wim_has_metadata(wim))
return WIMLIB_ERR_METADATA_NOT_FOUND;
if (!new_imd->modified)
return WIMLIB_ERR_INVALID_PARAM;
- ret = select_wim_image(wim, template_image);
+ ret = select_wim_image(template_wim, template_image);
if (ret)
return ret;
+ struct reference_template_args args = {
+ .wim = wim,
+ .template_wim = template_wim,
+ };
+
ret = for_dentry_in_tree(new_imd->root_dentry,
- dentry_reference_template, wim);
+ dentry_reference_template, &args);
dentry_tree_clear_inode_visited(new_imd->root_dentry);
return ret;
}
git://wimlib.net / wimlib / blobdiff