/*
* hardlink.c
*
- * Code to deal with hard links in WIMs. Essentially, the WIM dentries are put
- * into a hash table indexed by the inode ID field, then for each hard
- * inode, a linked list is made to connect the dentries.
+ * Code to deal with hard links in WIMs.
*/
/*
/* NULL NULL
* ^ ^
- * dentry | |
- * / \ ----------- -----------
+ * dentry | |
+ * / \ ----------- -----------
* | dentry<---| struct | | struct |---> dentry
- * \ / | inode | | inode |
+ * \ / | wim_inode| | wim_inode|
* dentry ------------ ------------
* ^ ^
* | |
* | | dentry
* ----------- ----------- / \
* dentry<---| struct | | struct |---> dentry dentry
- * / | inode | | inode | \ /
+ * / | wim_inode| | wim_inode| \ /
* dentry ------------ ------------ dentry
* ^ ^
* | |
* -----------------
- * inode_table->array | idx 0 | idx 1 |
+ * wim_inode_table->array | idx 0 | idx 1 |
* -----------------
*/
+/* Hash table to find inodes, identified by their inode ID.
+ * */
+struct wim_inode_table {
+ /* Fields for the hash table */
+ struct hlist_head *array;
+ u64 num_entries;
+ u64 capacity;
+
+ /*
+ * Linked list of "extra" inodes. These may be:
+ *
+ * - inodes with link count 1, which are all allowed to have 0 for their
+ * inode number, meaning we cannot insert them into the hash table
+ * before calling assign_inode_numbers().
+ *
+ * - Groups we create ourselves by splitting a nominal inode due to
+ * inconsistencies in the dentries. These inodes will share a inode
+ * number with some other inode until assign_inode_numbers() is
+ * called.
+ */
+ struct hlist_head extra_inodes;
+};
+
+static inline void destroy_inode_table(struct wim_inode_table *table)
+{
+ FREE(table->array);
+}
-int init_inode_table(struct inode_table *table, size_t capacity)
+static int init_inode_table(struct wim_inode_table *table, size_t capacity)
{
table->array = CALLOC(capacity, sizeof(table->array[0]));
if (!table->array) {
return 0;
}
-
-static size_t inode_link_count(const struct inode *inode)
+static inline size_t inode_link_count(const struct wim_inode *inode)
{
const struct list_head *cur;
size_t size = 0;
- list_for_each(cur, &inode->dentry_list)
+ list_for_each(cur, &inode->i_dentry)
size++;
return size;
}
-/*
- * Insert a dentry into the inode table based on its inode
- * ID.
- *
- * If there is already a dentry in the table having the same inode ID,
- * and the inode ID is not 0, the dentry is added to the circular
- * linked list for that inode.
- *
- * If the inode ID is 0, this indicates a dentry that's in a hard link
- * inode by itself (has a link count of 1). We can't insert it into the hash
- * table itself because we don't know what inode numbers are available to
- * give it (this could be kept track of but would be more difficult). Instead
- * we keep a linked list of the single dentries, and assign them inode
- * numbers later.
- */
-int inode_table_insert(struct dentry *dentry, void *__table)
+/* Insert a dentry into the inode table based on the inode number of the
+ * attached inode (which came from the hard link group ID field of the on-disk
+ * WIM dentry) */
+static int inode_table_insert(struct wim_dentry *dentry, void *__table)
{
- struct inode_table *table = __table;
- struct inode *d_inode = dentry->d_inode;
-
- if (d_inode->ino == 0) {
- /* Single inode--- Add to the list of extra inodes (we can't put
- * it in the table itself because all the singles have a link
- * inode ID of 0) */
- hlist_add_head(&d_inode->hlist, &table->extra_inodes);
-
- wimlib_assert(d_inode->dentry_list.next == &dentry->inode_dentry_list);
- wimlib_assert(d_inode->dentry_list.prev == &dentry->inode_dentry_list);
- wimlib_assert(d_inode->link_count == 1);
+ struct wim_inode_table *table = __table;
+ struct wim_inode *d_inode = dentry->d_inode;
+
+ if (d_inode->i_ino == 0) {
+ /* A dentry with a hard link group ID of 0 indicates that it's
+ * in a hard link group by itself. Add it to the list of extra
+ * inodes rather than inserting it into the hash lists. */
+ hlist_add_head(&d_inode->i_hlist, &table->extra_inodes);
+
+ wimlib_assert(d_inode->i_dentry.next == &dentry->d_alias);
+ wimlib_assert(d_inode->i_dentry.prev == &dentry->d_alias);
+ wimlib_assert(d_inode->i_nlink == 1);
} else {
- /* Inode that may have multiple corresponding dentries (the code
- * will work even if the inode actually contains only 1 dentry
- * though) */
-
size_t pos;
- struct inode *inode;
+ struct wim_inode *inode;
struct hlist_node *cur;
- /* Try adding to existing inode */
- pos = d_inode->ino % table->capacity;
- hlist_for_each_entry(inode, cur, &table->array[pos], hlist) {
- if (inode->ino == d_inode->ino) {
+ /* Try adding this dentry to an existing inode */
+ pos = d_inode->i_ino % table->capacity;
+ hlist_for_each_entry(inode, cur, &table->array[pos], i_hlist) {
+ if (inode->i_ino == d_inode->i_ino) {
inode_add_dentry(dentry, inode);
- inode->link_count++;
+ inode->i_nlink++;
return 0;
}
}
- /* Add new inode to the table */
- hlist_add_head(&d_inode->hlist, &table->array[pos]);
+ /* No inode in the table has the same number as this one, so add
+ * it to the table. */
+ hlist_add_head(&d_inode->i_hlist, &table->array[pos]);
- wimlib_assert(d_inode->dentry_list.next == &dentry->inode_dentry_list);
- wimlib_assert(d_inode->dentry_list.prev == &dentry->inode_dentry_list);
- wimlib_assert(d_inode->link_count == 1);
+ wimlib_assert(d_inode->i_dentry.next == &dentry->d_alias);
+ wimlib_assert(d_inode->i_dentry.prev == &dentry->d_alias);
+ wimlib_assert(d_inode->i_nlink == 1);
/* XXX Make the table grow when too many entries have been
* inserted. */
return 0;
}
-/* Assign the inode numbers to dentries in a inode table, and return the
- * next available inode ID. */
-u64 assign_inode_numbers(struct hlist_head *inode_list)
+static void print_inode_dentries(const struct wim_inode *inode)
{
- DEBUG("Assigning inode numbers");
- struct inode *inode;
- struct hlist_node *cur;
- u64 cur_ino = 1;
- hlist_for_each_entry(inode, cur, inode_list, hlist) {
- inode->ino = cur_ino;
- cur_ino++;
- }
- return cur_ino;
-}
-
-
-static void print_inode_dentries(const struct inode *inode)
-{
- struct dentry *dentry;
+ struct wim_dentry *dentry;
inode_for_each_dentry(dentry, inode)
printf("`%s'\n", dentry->full_path_utf8);
}
-static void inconsistent_inode(const struct inode *inode)
+static void inconsistent_inode(const struct wim_inode *inode)
{
- ERROR("An inconsistent hard link group that we cannot correct has been "
- "detected");
+ ERROR("An inconsistent hard link group that cannot be corrected has "
+ "been detected");
ERROR("The dentries are located at the following paths:");
+#ifdef ENABLE_ERROR_MESSAGES
print_inode_dentries(inode);
+#endif
}
-static bool ref_inodes_consistent(const struct inode * restrict ref_inode_1,
- const struct inode * restrict ref_inode_2)
+static bool ref_inodes_consistent(const struct wim_inode * restrict ref_inode_1,
+ const struct wim_inode * restrict ref_inode_2)
{
wimlib_assert(ref_inode_1 != ref_inode_2);
- if (ref_inode_1->num_ads != ref_inode_2->num_ads)
+ if (ref_inode_1->i_num_ads != ref_inode_2->i_num_ads)
return false;
- if (ref_inode_1->security_id != ref_inode_2->security_id
- || ref_inode_1->attributes != ref_inode_2->attributes)
+ if (ref_inode_1->i_security_id != ref_inode_2->i_security_id
+ || ref_inode_1->i_attributes != ref_inode_2->i_attributes)
return false;
- for (unsigned i = 0; i <= ref_inode_1->num_ads; i++) {
+ for (unsigned i = 0; i <= ref_inode_1->i_num_ads; i++) {
const u8 *ref_1_hash, *ref_2_hash;
ref_1_hash = inode_stream_hash(ref_inode_1, i);
ref_2_hash = inode_stream_hash(ref_inode_2, i);
if (!hashes_equal(ref_1_hash, ref_2_hash))
return false;
- if (i && !ads_entries_have_same_name(&ref_inode_1->ads_entries[i - 1],
- &ref_inode_2->ads_entries[i - 1]))
+ if (i && !ads_entries_have_same_name(&ref_inode_1->i_ads_entries[i - 1],
+ &ref_inode_2->i_ads_entries[i - 1]))
return false;
}
return true;
}
-static bool inodes_consistent(const struct inode * restrict ref_inode,
- const struct inode * restrict inode)
+static bool inodes_consistent(const struct wim_inode * restrict ref_inode,
+ const struct wim_inode * restrict inode)
{
wimlib_assert(ref_inode != inode);
- if (ref_inode->num_ads != inode->num_ads &&
- inode->num_ads != 0)
+ if (ref_inode->i_num_ads != inode->i_num_ads &&
+ inode->i_num_ads != 0)
return false;
- if (ref_inode->security_id != inode->security_id
- || ref_inode->attributes != inode->attributes)
+ if (ref_inode->i_security_id != inode->i_security_id
+ || ref_inode->i_attributes != inode->i_attributes)
return false;
- for (unsigned i = 0; i <= min(ref_inode->num_ads, inode->num_ads); i++) {
+ for (unsigned i = 0; i <= min(ref_inode->i_num_ads, inode->i_num_ads); i++) {
const u8 *ref_hash, *hash;
ref_hash = inode_stream_hash(ref_inode, i);
hash = inode_stream_hash(inode, i);
if (!hashes_equal(ref_hash, hash) && !is_zero_hash(hash))
return false;
- if (i && !ads_entries_have_same_name(&ref_inode->ads_entries[i - 1],
- &inode->ads_entries[i - 1]))
+ if (i && !ads_entries_have_same_name(&ref_inode->i_ads_entries[i - 1],
+ &inode->i_ads_entries[i - 1]))
return false;
}
return true;
}
/* Fix up a "true" inode and check for inconsistencies */
-static int fix_true_inode(struct inode *inode)
+static int fix_true_inode(struct wim_inode *inode, struct hlist_head *inode_list)
{
- struct dentry *dentry;
- struct dentry *ref_dentry = NULL;
- struct inode *ref_inode;
+ struct wim_dentry *dentry;
+ struct wim_dentry *ref_dentry = NULL;
+ struct wim_inode *ref_inode;
u64 last_ctime = 0;
u64 last_mtime = 0;
u64 last_atime = 0;
inode_for_each_dentry(dentry, inode) {
- if (!ref_dentry || dentry->d_inode->num_ads > ref_dentry->d_inode->num_ads)
+ if (!ref_dentry || dentry->d_inode->i_num_ads > ref_dentry->d_inode->i_num_ads)
ref_dentry = dentry;
- if (dentry->d_inode->creation_time > last_ctime)
- last_ctime = dentry->d_inode->creation_time;
- if (dentry->d_inode->last_write_time > last_mtime)
- last_mtime = dentry->d_inode->last_write_time;
- if (dentry->d_inode->last_access_time > last_atime)
- last_atime = dentry->d_inode->last_access_time;
+ if (dentry->d_inode->i_creation_time > last_ctime)
+ last_ctime = dentry->d_inode->i_creation_time;
+ if (dentry->d_inode->i_last_write_time > last_mtime)
+ last_mtime = dentry->d_inode->i_last_write_time;
+ if (dentry->d_inode->i_last_access_time > last_atime)
+ last_atime = dentry->d_inode->i_last_access_time;
}
ref_inode = ref_dentry->d_inode;
- ref_inode->link_count = 1;
+ ref_inode->i_nlink = 1;
+ hlist_add_head(&ref_inode->i_hlist, inode_list);
- list_del(&inode->dentry_list);
- list_add(&ref_inode->dentry_list, &ref_dentry->inode_dentry_list);
+ list_del(&inode->i_dentry);
+ list_add(&ref_inode->i_dentry, &ref_dentry->d_alias);
inode_for_each_dentry(dentry, ref_inode) {
if (dentry != ref_dentry) {
inconsistent_inode(ref_inode);
return WIMLIB_ERR_INVALID_DENTRY;
}
- /* Free the unneeded `struct inode'. */
+ /* Free the unneeded `struct wim_inode'. */
+ dentry->d_inode->i_hlist.next = NULL;
+ dentry->d_inode->i_hlist.pprev = NULL;
free_inode(dentry->d_inode);
dentry->d_inode = ref_inode;
- ref_inode->link_count++;
+ ref_inode->i_nlink++;
}
}
- ref_inode->creation_time = last_ctime;
- ref_inode->last_write_time = last_mtime;
- ref_inode->last_access_time = last_atime;
- wimlib_assert(inode_link_count(ref_inode) == ref_inode->link_count);
+ ref_inode->i_creation_time = last_ctime;
+ ref_inode->i_last_write_time = last_mtime;
+ ref_inode->i_last_access_time = last_atime;
+ wimlib_assert(inode_link_count(ref_inode) == ref_inode->i_nlink);
return 0;
}
-/*
+/*
* Fixes up a nominal inode.
*
- * By a nominal inode we mean a group of two or more dentries that share
- * the same hard link group ID.
+ * By a nominal inode we mean a group of two or more dentries that share the
+ * same hard link group ID.
*
* If dentries in the inode are found to be inconsistent, we may split the inode
* into several "true" inodes.
*
* After splitting up each nominal inode into the "true" inodes we will
* canonicalize the link group by getting rid of all the unnecessary `struct
- * inodes'. There will be just one `struct inode' for each hard link group
- * remaining.
+ * wim_inode's. There will be just one `struct wim_inode' for each hard link
+ * group remaining.
*/
-static int
-fix_nominal_inode(struct inode *inode, struct hlist_head *inode_list)
+static int fix_nominal_inode(struct wim_inode *inode,
+ struct hlist_head *inode_list)
{
- struct dentry *dentry, *ref_dentry;
+ struct wim_dentry *dentry;
struct hlist_node *cur, *tmp;
int ret;
size_t num_true_inodes;
- wimlib_assert(inode->link_count == inode_link_count(inode));
+ wimlib_assert(inode->i_nlink == inode_link_count(inode));
LIST_HEAD(dentries_with_data_streams);
LIST_HEAD(dentries_with_no_data_streams);
* least one data stream with a non-zero hash, and another list that
* contains the dentries that have a zero hash for all data streams. */
inode_for_each_dentry(dentry, inode) {
- for (unsigned i = 0; i <= dentry->d_inode->num_ads; i++) {
+ for (unsigned i = 0; i <= dentry->d_inode->i_num_ads; i++) {
const u8 *hash;
hash = inode_stream_hash(dentry->d_inode, i);
if (!is_zero_hash(hash)) {
* inode to be a true inode */
if (list_empty(&dentries_with_data_streams)) {
#ifdef ENABLE_DEBUG
- if (inode->link_count > 1) {
- DEBUG("Found link group of size %zu without "
- "any data streams:", inode->link_count);
+ if (inode->i_nlink > 1) {
+ DEBUG("Found link group of size %u without "
+ "any data streams:", inode->i_nlink);
print_inode_dentries(inode);
DEBUG("We are going to interpret it as true "
"link group, provided that the dentries "
"are consistent.");
}
#endif
- hlist_add_head(&inode->hlist, inode_list);
- return fix_true_inode(inode);
+ return fix_true_inode(inode, inode_list);
}
/* One or more dentries had data streams specified. We check each of
* add this dentry to it. Or, if none of the true inodes are
* consistent with this dentry, add a new one (if that happens,
* we have split the hard link group). */
- hlist_for_each_entry(inode, cur, &true_inodes, hlist) {
+ hlist_for_each_entry(inode, cur, &true_inodes, i_hlist) {
if (ref_inodes_consistent(inode, dentry->d_inode)) {
inode_add_dentry(dentry, inode);
goto next_dentry_2;
}
}
num_true_inodes++;
- INIT_LIST_HEAD(&dentry->d_inode->dentry_list);
+ INIT_LIST_HEAD(&dentry->d_inode->i_dentry);
inode_add_dentry(dentry, dentry->d_inode);
- hlist_add_head(&dentry->d_inode->hlist, &true_inodes);
+ hlist_add_head(&dentry->d_inode->i_hlist, &true_inodes);
next_dentry_2:
;
}
if (num_true_inodes != 1) {
ERROR("Hard inode ambiguity detected!");
ERROR("We split up inode 0x%"PRIx64" due to "
- "inconsistencies,", inode->ino);
+ "inconsistencies,", inode->i_ino);
ERROR("but dentries with no stream information remained. "
"We don't know which inode");
ERROR("to assign them to.");
return WIMLIB_ERR_INVALID_DENTRY;
}
- inode = container_of(true_inodes.first, struct inode, hlist);
+ inode = container_of(true_inodes.first, struct wim_inode, i_hlist);
/* Assign the streamless dentries to the one and only true
* inode. */
list_for_each_entry(dentry, &dentries_with_no_data_streams, tmp_list)
}
#ifdef ENABLE_DEBUG
if (num_true_inodes != 1) {
- inode = container_of(true_inodes.first, struct inode, hlist);
+ inode = container_of(true_inodes.first, struct wim_inode, i_hlist);
printf("Split nominal inode 0x%"PRIx64" into %zu "
"inodes:\n",
- inode->ino, num_true_inodes);
+ inode->i_ino, num_true_inodes);
puts("------------------------------------------------------------------------------");
size_t i = 1;
- hlist_for_each_entry(inode, cur, &true_inodes, hlist) {
+ hlist_for_each_entry(inode, cur, &true_inodes, i_hlist) {
printf("[Split inode %zu]\n", i++);
print_inode_dentries(inode);
putchar('\n');
}
#endif
- hlist_for_each_entry_safe(inode, cur, tmp, &true_inodes, hlist) {
- hlist_add_head(&inode->hlist, inode_list);
- ret = fix_true_inode(inode);
+ hlist_for_each_entry_safe(inode, cur, tmp, &true_inodes, i_hlist) {
+ ret = fix_true_inode(inode, inode_list);
if (ret != 0)
return ret;
}
return 0;
}
-/*
- * Goes through each hard link group (dentries sharing the same hard link group
- * ID field) that's been inserted into the inode table and shares the `struct
- * inode's among members of each hard link group.
- *
- * In the process, the dentries belonging to each inode are checked for
- * consistency. If they contain data features that indicate they cannot really
- * correspond to the same inode, this should be an error, but in reality this
- * case needs to be handled, so we split the dentries into different inodes.
- *
- * After this function returns, the inodes are no longer in the inode table, and
- * the inode table should be destroyed. A list of the inodes, including all
- * split inodes as well as the inodes that were good before, is returned in the
- * list @inode_list.
- */
-int fix_inodes(struct inode_table *table, struct hlist_head *inode_list)
+static int fix_inodes(struct wim_inode_table *table,
+ struct hlist_head *inode_list)
{
- struct inode *inode;
+ struct wim_inode *inode;
struct hlist_node *cur, *tmp;
int ret;
INIT_HLIST_HEAD(inode_list);
for (u64 i = 0; i < table->capacity; i++) {
- hlist_for_each_entry_safe(inode, cur, tmp, &table->array[i], hlist) {
+ hlist_for_each_entry_safe(inode, cur, tmp, &table->array[i], i_hlist) {
ret = fix_nominal_inode(inode, inode_list);
if (ret != 0)
return ret;
hlist_add_head(cur, inode_list);
return 0;
}
+
+/*
+ * dentry_tree_fix_inodes():
+ *
+ * This function takes as input a tree of WIM dentries that initially has a
+ * different inode associated with each dentry. Sets of dentries that should
+ * share the same inode (a.k.a. hard link groups) are built using the i_ino
+ * field of each inode, then the link count and alias list for one inode in each
+ * set is set correctly and the unnecessary struct wim_inode's freed. The
+ * effect is to correctly associate exactly one struct wim_inode with each
+ * original inode, regardless of how many dentries are aliases for that inode.
+ *
+ * The special inode number of 0 indicates that the dentry is in a hard link
+ * group by itself, and therefore has a 'struct wim_inode' with i_nlink=1 to
+ * itself.
+ *
+ * This function also checks the dentries in each hard link group for
+ * consistency. In some WIMs, such as install.wim for some versions of Windows
+ * 7, dentries can share the same hard link group ID but not actually be hard
+ * linked to each other (based on conflicting information, such as file
+ * contents). This should be an error, but this case needs be handled. So,
+ * each "nominal" inode (the inode based on the inode numbers provided in the
+ * WIM) is examined for consistency and may be split into multiple "true" inodes
+ * that are maximally sized consistent sets of dentries.
+ *
+ * Return 0 on success; WIMLIB_ERR_NOMEM or WIMLIB_ERR_INVALID_DENTRY on
+ * failure. On success, the list of "true" inodes, linked by the i_hlist field,
+ * is returned in the hlist @inode_list.
+ */
+int dentry_tree_fix_inodes(struct wim_dentry *root, struct hlist_head *inode_list)
+{
+ struct wim_inode_table inode_tab;
+ int ret;
+
+ DEBUG("Inserting dentries into inode table");
+ ret = init_inode_table(&inode_tab, 9001);
+ if (ret != 0)
+ return ret;
+
+ for_dentry_in_tree(root, inode_table_insert, &inode_tab);
+
+ DEBUG("Cleaning up the hard link groups");
+ ret = fix_inodes(&inode_tab, inode_list);
+ destroy_inode_table(&inode_tab);
+ return ret;
+}
+
+/* Assign inode numbers to a list of inodes and return the next available
+ * number. */
+u64 assign_inode_numbers(struct hlist_head *inode_list)
+{
+ DEBUG("Assigning inode numbers");
+ struct wim_inode *inode;
+ struct hlist_node *cur;
+ u64 cur_ino = 1;
+ hlist_for_each_entry(inode, cur, inode_list, i_hlist) {
+ inode->i_ino = cur_ino;
+ cur_ino++;
+ }
+ return cur_ino;
+}
git://wimlib.net / wimlib / blobdiff