]> wimlib.net Git - wimlib/blobdiff - src/hardlink.c
write_pipable_wim(): Fix/improve comment
[wimlib] / src / hardlink.c
index 388d125a6e099a8438f751ab5a1399ccd2b36a45..3f316f1d993d1f84fa9852fde53e9ec900ad3f09 100644 (file)
  * along with wimlib; if not, see http://www.gnu.org/licenses/.
  */
 
-#include "wimlib_internal.h"
-#include "dentry.h"
-#include "list.h"
-#include "lookup_table.h"
+#ifdef HAVE_CONFIG_H
+#  include "config.h"
+#endif
+
+#include "wimlib/capture.h"
+#include "wimlib/dentry.h"
+#include "wimlib/error.h"
+#include "wimlib/lookup_table.h"
 
 /*                             NULL        NULL
  *                              ^           ^
@@ -88,10 +92,6 @@ inode_table_insert(struct wim_dentry *dentry, void *_table)
                 * in a hard link group by itself.  Add it to the list of extra
                 * inodes rather than inserting it into the hash lists. */
                list_add_tail(&d_inode->i_list, &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 {
                size_t pos;
                struct wim_inode *inode;
@@ -101,8 +101,16 @@ inode_table_insert(struct wim_dentry *dentry, void *_table)
                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) {
+                               if (unlikely((inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) ||
+                                            (d_inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY)))
+                               {
+                                       ERROR("Unsupported directory hard link "
+                                             "\"%"TS"\" <=> \"%"TS"\"",
+                                             dentry_full_path(dentry),
+                                             dentry_full_path(inode_first_dentry(inode)));
+                                       return WIMLIB_ERR_INVALID_METADATA_RESOURCE;
+                               }
                                inode_add_dentry(dentry, inode);
-                               inode->i_nlink++;
                                return 0;
                        }
                }
@@ -111,10 +119,6 @@ inode_table_insert(struct wim_dentry *dentry, void *_table)
                 * it to the table. */
                hlist_add_head(&d_inode->i_hlist, &table->array[pos]);
 
-               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. */
                table->num_entries++;
@@ -176,11 +180,16 @@ inode_table_new_dentry(struct wim_inode_table *table, const tchar *name,
        int ret;
 
        if (noshare) {
+               /* File that cannot be hardlinked--- Return a new inode with its
+                * inode and device numbers left at 0. */
                ret = new_dentry_with_timeless_inode(name, &dentry);
                if (ret)
                        return ret;
                list_add_tail(&dentry->d_inode->i_list, &table->extra_inodes);
        } else {
+               /* File that can be hardlinked--- search the table for an
+                * existing inode matching the inode number and device;
+                * otherwise create a new inode. */
                ret = new_dentry(name, &dentry);
                if (ret)
                        return ret;
@@ -189,6 +198,8 @@ inode_table_new_dentry(struct wim_inode_table *table, const tchar *name,
                        free_dentry(dentry);
                        return WIMLIB_ERR_NOMEM;
                }
+               /* If using an existing inode, we need to gain a reference to
+                * each of its streams. */
                if (inode->i_nlink > 1)
                        inode_ref_streams(inode);
                dentry->d_inode = inode;
@@ -198,25 +209,23 @@ inode_table_new_dentry(struct wim_inode_table *table, const tchar *name,
        return 0;
 }
 
-#if defined(ENABLE_ERROR_MESSAGES) || defined(ENABLE_DEBUG)
-static void
+static inline void
 print_inode_dentries(const struct wim_inode *inode)
 {
        struct wim_dentry *dentry;
        inode_for_each_dentry(dentry, inode)
                tfprintf(stderr, T("%"TS"\n"), dentry_full_path(dentry));
 }
-#endif
 
 static void
 inconsistent_inode(const struct wim_inode *inode)
 {
-#ifdef ENABLE_ERROR_MESSAGES
-       ERROR("An inconsistent hard link group that cannot be corrected has "
-             "been detected");
-       ERROR("The dentries are located at the following paths:");
-       print_inode_dentries(inode);
-#endif
+       if (wimlib_print_errors) {
+               ERROR("An inconsistent hard link group that cannot be corrected has "
+                     "been detected");
+               ERROR("The dentries are located at the following paths:");
+               print_inode_dentries(inode);
+       }
 }
 
 static bool
@@ -292,7 +301,7 @@ fix_true_inode(struct wim_inode *inode, struct list_head *inode_list)
        }
 
        ref_inode = ref_dentry->d_inode;
-       ref_inode->i_nlink = 1;
+       wimlib_assert(ref_inode->i_nlink == 1);
        list_add_tail(&ref_inode->i_list, inode_list);
 
        list_del(&inode->i_dentry);
@@ -302,9 +311,10 @@ fix_true_inode(struct wim_inode *inode, struct list_head *inode_list)
                if (dentry != ref_dentry) {
                        if (!inodes_consistent(ref_inode, dentry->d_inode)) {
                                inconsistent_inode(ref_inode);
-                               return WIMLIB_ERR_INVALID_DENTRY;
+                               return WIMLIB_ERR_INVALID_METADATA_RESOURCE;
                        }
                        /* Free the unneeded `struct wim_inode'. */
+                       wimlib_assert(dentry->d_inode->i_nlink == 1);
                        free_inode(dentry->d_inode);
                        dentry->d_inode = ref_inode;
                        ref_inode->i_nlink++;
@@ -340,8 +350,6 @@ fix_nominal_inode(struct wim_inode *inode, struct list_head *inode_list,
        int ret;
        size_t num_true_inodes;
 
-       wimlib_assert(inode->i_nlink == inode_link_count(inode));
-
        LIST_HEAD(dentries_with_data_streams);
        LIST_HEAD(dentries_with_no_data_streams);
        HLIST_HEAD(true_inodes);
@@ -369,9 +377,10 @@ fix_nominal_inode(struct wim_inode *inode, struct list_head *inode_list,
         * inode to be a true inode */
        if (list_empty(&dentries_with_data_streams)) {
        #ifdef ENABLE_DEBUG
-               if (inode->i_nlink > 1) {
+               unsigned nominal_group_size = inode_link_count(inode);
+               if (nominal_group_size > 1) {
                        DEBUG("Found link group of size %u without "
-                             "any data streams:", inode->i_nlink);
+                             "any data streams:", nominal_group_size);
                        print_inode_dentries(inode);
                        DEBUG("We are going to interpret it as true "
                              "link group, provided that the dentries "
@@ -411,13 +420,14 @@ next_dentry_2:
          * streamless dentries to. */
        if (!list_empty(&dentries_with_no_data_streams)) {
                if (num_true_inodes != 1) {
-                       ERROR("Hard inode ambiguity detected!");
+                       ERROR("Hard link ambiguity detected!");
                        ERROR("We split up inode 0x%"PRIx64" due to "
                              "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;
+                       ret = WIMLIB_ERR_INVALID_METADATA_RESOURCE;
+                       goto out_cleanup_true_inode_list;
                }
                inode = container_of(true_inodes.first, struct wim_inode, i_hlist);
                /* Assign the streamless dentries to the one and only true
@@ -446,11 +456,18 @@ next_dentry_2:
         }
 
        hlist_for_each_entry_safe(inode, cur, tmp, &true_inodes, i_hlist) {
+               hlist_del_init(&inode->i_hlist);
                ret = fix_true_inode(inode, inode_list);
                if (ret)
-                       return ret;
+                       goto out_cleanup_true_inode_list;
        }
-       return 0;
+       ret = 0;
+       goto out;
+out_cleanup_true_inode_list:
+       hlist_for_each_entry_safe(inode, cur, tmp, &true_inodes, i_hlist)
+               hlist_del_init(&inode->i_hlist);
+out:
+       return ret;
 }
 
 static int
@@ -463,7 +480,7 @@ fix_inodes(struct wim_inode_table *table, struct list_head *inode_list,
        INIT_LIST_HEAD(inode_list);
        for (u64 i = 0; i < table->capacity; i++) {
                hlist_for_each_entry_safe(inode, cur, tmp, &table->array[i], i_hlist) {
-                       INIT_LIST_HEAD(&inode->i_list);
+                       hlist_del_init(&inode->i_hlist);
                        ret = fix_nominal_inode(inode, inode_list, ino_changes_needed);
                        if (ret)
                                return ret;
@@ -497,9 +514,13 @@ fix_inodes(struct wim_inode_table *table, struct list_head *inode_list,
  * 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,
+ * On success, the list of "true" inodes, linked by the i_hlist field,
  * is returned in the hlist @inode_list.
+ *
+ * Return values:
+ *     WIMLIB_ERR_SUCCESS (0)
+ *     WIMLIB_ERR_INVALID_METADATA_RESOURCE
+ *     WIMLIB_ERR_NOMEM
  */
 int
 dentry_tree_fix_inodes(struct wim_dentry *root, struct list_head *inode_list)
@@ -507,22 +528,25 @@ dentry_tree_fix_inodes(struct wim_dentry *root, struct list_head *inode_list)
        struct wim_inode_table inode_tab;
        int ret;
        bool ino_changes_needed;
+       struct wim_inode *inode;
 
        DEBUG("Inserting dentries into inode table");
        ret = init_inode_table(&inode_tab, 9001);
        if (ret)
-               return ret;
+               goto out;
 
-       for_dentry_in_tree(root, inode_table_insert, &inode_tab);
+       ret = for_dentry_in_tree(root, inode_table_insert, &inode_tab);
+       if (ret)
+               goto out_destroy_inode_table;
 
        DEBUG("Cleaning up the hard link groups");
        ino_changes_needed = false;
        ret = fix_inodes(&inode_tab, inode_list, &ino_changes_needed);
-       destroy_inode_table(&inode_tab);
+       if (ret)
+               goto out_destroy_inode_table;
 
-       if (ret == 0 && ino_changes_needed) {
+       if (ino_changes_needed) {
                u64 cur_ino = 1;
-               struct wim_inode *inode;
 
                WARNING("Re-assigning inode numbers due to inode inconsistencies");
                list_for_each_entry(inode, inode_list, i_list) {
@@ -532,31 +556,60 @@ dentry_tree_fix_inodes(struct wim_dentry *root, struct list_head *inode_list)
                                inode->i_ino = 0;
                }
        }
+       /* On success, all the inodes have been moved to the image inode list,
+        * so there's no need to delete from from the hash lists in the inode
+        * table before freeing the hash buckets array directly. */
+       ret = 0;
+       goto out_destroy_inode_table_raw;
+out_destroy_inode_table:
+       for (size_t i = 0; i < inode_tab.capacity; i++) {
+               struct hlist_node *cur, *tmp;
+               hlist_for_each_entry_safe(inode, cur, tmp, &inode_tab.array[i], i_hlist)
+                       hlist_del_init(&inode->i_hlist);
+       }
+       {
+               struct wim_inode *tmp;
+               list_for_each_entry_safe(inode, tmp, &inode_tab.extra_inodes, i_list)
+                       list_del_init(&inode->i_list);
+       }
+out_destroy_inode_table_raw:
+       destroy_inode_table(&inode_tab);
+out:
        return ret;
 }
 
-/* Assign consecutive inode numbers to the inodes in the inode table, and move
- * the inodes to a single list @head. */
+/* Assign consecutive inode numbers to a new set of inodes from the inode table,
+ * and append the inodes to a single list @head that contains the inodes already
+ * existing in the WIM image.  */
 void
 inode_table_prepare_inode_list(struct wim_inode_table *table,
                               struct list_head *head)
 {
-       struct wim_inode *inode;
+       struct wim_inode *inode, *tmp_inode;
        struct hlist_node *cur, *tmp;
        u64 cur_ino = 1;
 
-       INIT_LIST_HEAD(head);
+       /* Re-assign inode numbers in the existing list to avoid duplicates. */
+       list_for_each_entry(inode, head, i_list)
+               inode->i_ino = cur_ino++;
+
+       /* Assign inode numbers to the new inodes and move them to the image's
+        * inode list. */
        for (size_t i = 0; i < table->capacity; i++) {
                hlist_for_each_entry_safe(inode, cur, tmp, &table->array[i], i_hlist)
                {
-                       if (inode->i_nlink > 1)
-                               inode->i_ino = cur_ino++;
-                       else
-                               inode->i_ino = 0;
+                       inode->i_ino = cur_ino++;
+                       inode->i_devno = 0;
                        list_add_tail(&inode->i_list, head);
                }
                INIT_HLIST_HEAD(&table->array[i]);
        }
-       list_splice_tail(&table->extra_inodes, head);
+       list_for_each_entry_safe(inode, tmp_inode, &table->extra_inodes, i_list)
+       {
+               inode->i_ino = cur_ino++;
+               inode->i_devno = 0;
+               list_add_tail(&inode->i_list, head);
+       }
+       INIT_LIST_HEAD(&table->extra_inodes);
        table->num_entries = 0;
 }