]> wimlib.net Git - wimlib/blobdiff - src/modify.c
wimlib_export() updates
[wimlib] / src / modify.c
index ae6f98b46231bc23b5dfd6bbe4595074b06a92a3..3e7e1c5684780f7fdf3a8a79c1f487bfae3bd73b 100644 (file)
@@ -44,7 +44,7 @@
  * the WIM image. */
 #define WIMLIB_ADD_IMAGE_FLAG_ROOT 0x80000000
 
-void destroy_image_metadata(struct image_metadata *imd,struct lookup_table *lt)
+void destroy_image_metadata(struct image_metadata *imd, struct lookup_table *lt)
 {
        free_dentry_tree(imd->root_dentry, lt);
        free_security_data(imd->security_data);
@@ -131,9 +131,9 @@ static int build_dentry_tree(struct dentry **root_ret, const char *root_disk_pat
        if (!root)
                return WIMLIB_ERR_NOMEM;
 
-       stbuf_to_inode(&root_stbuf, root->inode);
+       stbuf_to_inode(&root_stbuf, root->d_inode);
        add_flags &= ~WIMLIB_ADD_IMAGE_FLAG_ROOT;
-       root->inode->resolved = true;
+       root->d_inode->resolved = true;
 
        if (dentry_is_directory(root)) {
                /* Open the directory on disk */
@@ -184,7 +184,7 @@ static int build_dentry_tree(struct dentry **root_ret, const char *root_disk_pat
                }
                deref_name_buf[deref_name_len] = '\0';
                DEBUG("Read symlink `%s'", deref_name_buf);
-               ret = inode_set_symlink(root->inode, deref_name_buf,
+               ret = inode_set_symlink(root->d_inode, deref_name_buf,
                                        lookup_table, NULL);
        } else {
                /* Regular file */
@@ -226,7 +226,7 @@ static int build_dentry_tree(struct dentry **root_ret, const char *root_disk_pat
                        copy_hash(lte->hash, hash);
                        lookup_table_insert(lookup_table, lte);
                }
-               root->inode->lte = lte;
+               root->d_inode->lte = lte;
        }
 out:
        *root_ret = root;
@@ -236,42 +236,88 @@ out:
 struct wim_pair {
        WIMStruct *src_wim;
        WIMStruct *dest_wim;
+       struct list_head lte_list_head;
 };
 
+static int allocate_lte_if_needed(struct dentry *dentry, void *arg)
+{
+       const WIMStruct *src_wim, *dest_wim;
+       struct list_head *lte_list_head;
+       struct inode *inode;
+
+       src_wim = ((struct wim_pair*)arg)->src_wim;
+       dest_wim = ((struct wim_pair*)arg)->dest_wim;
+       lte_list_head = &((struct wim_pair*)arg)->lte_list_head;
+       inode = dentry->d_inode;
+
+       wimlib_assert(!inode->resolved);
+
+       for (unsigned i = 0; i <= inode->num_ads; i++) {
+               struct lookup_table_entry *src_lte, *dest_lte;
+               src_lte = inode_stream_lte_unresolved(inode, i,
+                                                     src_wim->lookup_table);
+
+               if (src_lte && ++src_lte->out_refcnt == 1) {
+                       dest_lte = inode_stream_lte_unresolved(inode, i,
+                                                              dest_wim->lookup_table);
+
+                       if (!dest_lte) {
+                               dest_lte = clone_lookup_table_entry(src_lte);
+                               if (!dest_lte)
+                                       return WIMLIB_ERR_NOMEM;
+                               list_add_tail(&dest_lte->list, lte_list_head);
+                       }
+               }
+       }
+       return 0;
+}
+
 /* 
  * This function takes in a dentry that was previously located only in image(s)
- * in @src_wim, but now is being added to @dest_wim. If there is in fact already a
- * lookup table entry for this file in the lookup table of the destination WIM
- * file, we simply increment its reference count.  Otherwise, a new lookup table
- * entry is created that references the location of the file resource in the
- * source WIM file through the other_wim_fp field of the lookup table entry.
+ * in @src_wim, but now is being added to @dest_wim.  For each stream associated
+ * with the dentry, if there is already a lookup table entry for that stream in
+ * the lookup table of the destination WIM file, its reference count is
+ * incrementej.  Otherwise, a new lookup table entry is created that points back
+ * to the stream in the source WIM file (through the @hash field combined with
+ * the @wim field of the lookup table entry.)
  */
 static int add_lte_to_dest_wim(struct dentry *dentry, void *arg)
 {
        WIMStruct *src_wim, *dest_wim;
+       struct inode *inode;
 
        src_wim = ((struct wim_pair*)arg)->src_wim;
        dest_wim = ((struct wim_pair*)arg)->dest_wim;
+       inode = dentry->d_inode;
 
-       wimlib_assert(!dentry->inode->resolved);
+       wimlib_assert(!inode->resolved);
 
-       for (unsigned i = 0; i < (unsigned)dentry->inode->num_ads + 1; i++) {
+       for (unsigned i = 0; i <= inode->num_ads; i++) {
                struct lookup_table_entry *src_lte, *dest_lte;
-               src_lte = inode_stream_lte_unresolved(dentry->inode, i,
+               src_lte = inode_stream_lte_unresolved(inode, i,
                                                      src_wim->lookup_table);
-               if (!src_lte)
+
+               if (!src_lte) /* Empty or nonexistent stream. */
                        continue;
-               dest_lte = inode_stream_lte_unresolved(dentry->inode, i,
+
+               dest_lte = inode_stream_lte_unresolved(inode, i,
                                                       dest_wim->lookup_table);
                if (dest_lte) {
                        dest_lte->refcnt++;
                } else {
-                       dest_lte = MALLOC(sizeof(struct lookup_table_entry));
-                       if (!dest_lte)
-                               return WIMLIB_ERR_NOMEM;
-                       memcpy(dest_lte, src_lte, sizeof(struct lookup_table_entry));
+                       struct list_head *lte_list_head;
+                       struct list_head *next;
+
+                       lte_list_head = &((struct wim_pair*)arg)->lte_list_head;
+                       wimlib_assert(!list_empty(lte_list_head));
+
+                       next = lte_list_head->next;
+                       list_del(next);
+                       dest_lte = container_of(next, struct lookup_table_entry, list);
                        dest_lte->part_number = 1;
                        dest_lte->refcnt = 1;
+                       wimlib_assert(hashes_equal(dest_lte->hash, src_lte->hash));
+
                        lookup_table_insert(dest_wim->lookup_table, dest_lte);
                }
        }
@@ -285,6 +331,9 @@ static int add_lte_to_dest_wim(struct dentry *dentry, void *arg)
  *
  * Does not update the XML data.
  *
+ * On failure, WIMLIB_ERR_NOMEM is returned and no changes are made.  Otherwise,
+ * 0 is returned and the image metadata array of @w is modified.
+ *
  * @w:           The WIMStruct for the WIM file.
  * @root_dentry:  The root of the directory tree for the image.
  * @sd:                  The security data for the image.
@@ -295,7 +344,9 @@ static int add_new_dentry_tree(WIMStruct *w, struct dentry *root_dentry,
        struct lookup_table_entry *metadata_lte;
        struct image_metadata *imd;
        struct image_metadata *new_imd;
-       struct link_group_table *lgt;
+       int ret;
+
+       wimlib_assert(root_dentry != NULL);
 
        DEBUG("Reallocating image metadata array for image_count = %u",
              w->hdr.image_count + 1);
@@ -328,8 +379,12 @@ static int add_new_dentry_tree(WIMStruct *w, struct dentry *root_dentry,
        w->image_metadata       = imd;
        w->hdr.image_count++;
 
-       /* Change the current image to the new one. */
-       return wimlib_select_image(w, w->hdr.image_count);
+       /* Change the current image to the new one.  There should not be any
+        * ways for this to fail, since the image is valid and the dentry tree
+        * is already in memory. */
+       ret = wimlib_select_image(w, w->hdr.image_count);
+       wimlib_assert(ret == 0);
+       return ret;
 out_free_metadata_lte:
        FREE(metadata_lte);
 out_free_imd:
@@ -397,8 +452,7 @@ WIMLIBAPI int wimlib_export_image(WIMStruct *src_wim,
                                        export_flags &= ~WIMLIB_EXPORT_FLAG_BOOT;
 
                                ret = wimlib_export_image(src_wim, i, dest_wim, 
-                                                         NULL,
-                                                         dest_description,
+                                                         NULL, NULL,
                                                          export_flags,
                                                          additional_swms,
                                                          num_additional_swms);
@@ -417,6 +471,13 @@ WIMLIBAPI int wimlib_export_image(WIMStruct *src_wim,
                      dest_name, src_image);
        }
 
+       if (!dest_description) {
+               dest_description = wimlib_get_image_description(src_wim,
+                                                               src_image);
+               DEBUG("Using description `%s' for source image %d",
+                     dest_description, src_image);
+       }
+
        DEBUG("Exporting image %d from `%s'", src_image, src_wim->filename);
 
        if (wimlib_image_name_in_use(dest_wim, dest_name)) {
@@ -446,32 +507,56 @@ WIMLIBAPI int wimlib_export_image(WIMStruct *src_wim,
                goto out;
        }
 
-       /* Cleaning up here on failure would be hard.  For example, we could
-        * fail to allocate memory in add_lte_to_dest_wim(),
-        * leaving the lookup table entries in the destination WIM in an
-        * inconsistent state.  Until these issues can be resolved,
-        * wimlib_export_image() is documented as leaving dest_wim in an
-        * indeterminate state.  */
-       root = wim_root_dentry(src_wim);
-       sd = wim_security_data(src_wim);
-       for_dentry_in_tree(root, increment_dentry_refcnt, NULL);
+       /* Pre-allocate the new lookup table entries that will be needed.  This
+        * way, it's not possible to run out of memory part-way through
+        * modifying the lookup table of the destination WIM. */
        wims.src_wim = src_wim;
        wims.dest_wim = dest_wim;
-       ret = for_dentry_in_tree(root, add_lte_to_dest_wim, &wims);
+       INIT_LIST_HEAD(&wims.lte_list_head);
+       for_lookup_table_entry(src_wim->lookup_table, lte_zero_out_refcnt, NULL);
+       root = wim_root_dentry(src_wim);
+       for_dentry_in_tree(root, dentry_unresolve_ltes, NULL);
+       ret = for_dentry_in_tree(root, allocate_lte_if_needed, &wims);
        if (ret != 0)
-               goto out;
+               goto out_free_ltes;
+
+       ret = xml_export_image(src_wim->wim_info, src_image,
+                              &dest_wim->wim_info, dest_name, dest_description);
+       if (ret != 0)
+               goto out_free_ltes;
+
+       sd = wim_security_data(src_wim);
        ret = add_new_dentry_tree(dest_wim, root, sd);
        if (ret != 0)
-               goto out;
+               goto out_xml_delete_image;
+
+
+       /* All memory allocations have been taken care of, so it's no longer
+        * possible for this function to fail.  Go ahead and increment the
+        * reference counts of the dentry tree and security data, then update
+        * the lookup table of the destination WIM and the boot index, if
+        * needed. */
+       for_dentry_in_tree(root, increment_dentry_refcnt, NULL);
        sd->refcnt++;
+       for_dentry_in_tree(root, add_lte_to_dest_wim, &wims);
+       wimlib_assert(list_empty(&wims.lte_list_head));
 
        if (flags & WIMLIB_EXPORT_FLAG_BOOT) {
                DEBUG("Setting boot_idx to %d", dest_wim->hdr.image_count);
                dest_wim->hdr.boot_idx = dest_wim->hdr.image_count;
        }
+       ret = 0;
+       goto out;
+
+out_xml_delete_image:
+       xml_delete_image(&dest_wim->wim_info, dest_wim->hdr.image_count);
+out_free_ltes:
+       {
+               struct lookup_table_entry *lte, *tmp;
+               list_for_each_entry_safe(lte, tmp, &wims.lte_list_head, list)
+                       free_lookup_table_entry(lte);
+       }
 
-       ret = xml_export_image(src_wim->wim_info, src_image, &dest_wim->wim_info,
-                              dest_name, dest_description);
 out:
        if (num_additional_swms) {
                free_lookup_table(src_wim->lookup_table);
@@ -889,7 +974,7 @@ int do_add_image(WIMStruct *w, const char *dir, const char *name,
        if (flags & WIMLIB_ADD_IMAGE_FLAG_BOOT)
                wimlib_set_boot_idx(w, w->hdr.image_count);
 
-       ret = xml_add_image(w, root_dentry, name);
+       ret = xml_add_image(w, name);
        if (ret != 0)
                goto out_destroy_imd;