4 * Support for modifying WIM files with image-level operations (delete an image,
5 * add an image, export an imagex from one WIM to another.) There is nothing
6 * here that lets you change individual files in the WIM; for that you will need
7 * to look at the filesystem implementation in mount.c.
11 * Copyright (C) 2012 Eric Biggers
13 * This file is part of wimlib, a library for working with WIM files.
15 * wimlib is free software; you can redistribute it and/or modify it under the
16 * terms of the GNU Lesser General Public License as published by the Free
17 * Software Foundation; either version 2.1 of the License, or (at your option)
20 * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
21 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
22 * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
25 * You should have received a copy of the GNU Lesser General Public License
26 * along with wimlib; if not, see http://www.gnu.org/licenses/.
29 #include "wimlib_internal.h"
34 #include "lookup_table.h"
41 /** Private flag: Used to mark that we currently adding the root directory of
43 #define WIMLIB_ADD_IMAGE_FLAG_ROOT 0x80000000
45 static void destroy_image_metadata(struct image_metadata *imd,
46 struct lookup_table *lt)
48 free_dentry_tree(imd->root_dentry, lt, true);
49 free_security_data(imd->security_data);
51 /* Get rid of the lookup table entry for this image's metadata resource
53 lookup_table_remove(lt, imd->metadata_lte);
57 * Recursively builds a dentry tree from a directory tree on disk, outside the
60 * @root: A dentry that has already been created for the root of the dentry
62 * @source_path: The path to the root of the tree on disk.
63 * @root_stat: A pointer to a `struct stat' that contains the metadata for the
64 * root of the tree on disk.
65 * @lookup_table: The lookup table for the WIM file. For each file added to the
66 * dentry tree being built, an entry is added to the lookup table,
67 * unless an identical file is already in the lookup table. These
68 * lookup table entries that are added point to the file on disk.
70 * @return: 0 on success, nonzero on failure. It is a failure if any of
71 * the files cannot be `stat'ed, or if any of the needed
72 * directories cannot be opened or read. Failure to add the files
73 * to the WIM may still occur later when trying to actually read
74 * the regular files in the tree into the WIM as file resources.
76 static int build_dentry_tree(struct dentry *root, const char *root_disk_path,
77 struct lookup_table* lookup_table,
80 DEBUG("`%s'", root_disk_path);
81 struct stat root_stbuf;
83 int (*stat_fn)(const char *restrict, struct stat *restrict);
85 if (add_flags & WIMLIB_ADD_IMAGE_FLAG_DEREFERENCE)
91 ret = (*stat_fn)(root_disk_path, &root_stbuf);
93 ERROR_WITH_ERRNO("Failed to stat `%s'", root_disk_path);
94 return WIMLIB_ERR_STAT;
97 if ((add_flags & WIMLIB_ADD_IMAGE_FLAG_ROOT) &&
98 !S_ISDIR(root_stbuf.st_mode)) {
99 ERROR("`%s' is not a directory", root_disk_path);
100 return WIMLIB_ERR_NOTDIR;
102 stbuf_to_dentry(&root_stbuf, root);
103 add_flags &= ~WIMLIB_ADD_IMAGE_FLAG_ROOT;
105 if (dentry_is_directory(root)) {
106 /* Open the directory on disk */
109 struct dentry *child;
111 dir = opendir(root_disk_path);
113 ERROR_WITH_ERRNO("Failed to open the directory `%s'",
115 return WIMLIB_ERR_OPEN;
118 /* Buffer for names of files in directory. */
119 size_t len = strlen(root_disk_path);
120 char name[len + 1 + FILENAME_MAX + 1];
121 memcpy(name, root_disk_path, len);
124 /* Create a dentry for each entry in the directory on disk, and recurse
125 * to any subdirectories. */
126 while ((p = readdir(dir)) != NULL) {
127 if (p->d_name[0] == '.' && (p->d_name[1] == '\0'
128 || (p->d_name[1] == '.' && p->d_name[2] == '\0')))
130 strcpy(name + len + 1, p->d_name);
131 child = new_dentry(p->d_name);
133 ERROR("No memory to allocate new dentry");
134 return WIMLIB_ERR_NOMEM;
136 ret = build_dentry_tree(child, name, lookup_table,
138 link_dentry(child, root);
143 } else if (dentry_is_symlink(root)) {
144 /* Archiving a symbolic link */
145 size_t symlink_buf_len;
146 char deref_name_buf[4096];
147 ssize_t ret = readlink(root_disk_path, deref_name_buf,
148 sizeof(deref_name_buf) - 1);
150 ERROR_WITH_ERRNO("Failed to read target of "
151 "symbolic link `%s'", root_disk_path);
152 return WIMLIB_ERR_STAT;
154 deref_name_buf[ret] = '\0';
155 DEBUG("Read symlink `%s'", deref_name_buf);
156 void *symlink_buf = make_symlink_reparse_data_buf(deref_name_buf,
159 return WIMLIB_ERR_NOMEM;
160 DEBUG("Made symlink reparse data buf (len = %zu, name len = %zu)",
161 symlink_buf_len, ret);
163 u8 symlink_buf_hash[WIM_HASH_SIZE];
164 sha1_buffer(symlink_buf, symlink_buf_len, symlink_buf_hash);
166 ret = dentry_set_symlink_buf(root, symlink_buf_hash);
172 DEBUG("Created symlink buf");
174 struct lookup_table_entry *lte;
175 struct lookup_table_entry *existing_lte;
177 existing_lte = lookup_resource(lookup_table, symlink_buf_hash);
179 existing_lte->refcnt++;
181 DEBUG("Creating new lookup table entry");
182 lte = new_lookup_table_entry();
185 return WIMLIB_ERR_NOMEM;
187 lte->symlink_buf = symlink_buf;
188 lte->resource_entry.original_size = symlink_buf_len;
189 lte->resource_entry.size = symlink_buf_len;
190 lte->is_symlink = true;
191 memcpy(lte->hash, symlink_buf_hash, WIM_HASH_SIZE);
192 lookup_table_insert(lookup_table, lte);
195 struct lookup_table_entry *lte;
197 /* For each non-directory, we must check to see if the file is
198 * in the lookup table already; if it is, we increment its
199 * refcnt; otherwise, we create a new lookup table entry and
201 ret = sha1sum(root_disk_path, root->hash);
205 lte = lookup_resource(lookup_table, root->hash);
209 char *file_on_disk = STRDUP(root_disk_path);
211 ERROR("Failed to allocate memory for file path");
212 return WIMLIB_ERR_NOMEM;
214 lte = new_lookup_table_entry();
217 return WIMLIB_ERR_NOMEM;
219 lte->file_on_disk = file_on_disk;
220 lte->resource_entry.original_size = root_stbuf.st_size;
221 lte->resource_entry.size = root_stbuf.st_size;
222 memcpy(lte->hash, root->hash, WIM_HASH_SIZE);
223 lookup_table_insert(lookup_table, lte);
235 * This function takes in a dentry that was previously located only in image(s)
236 * in @src_wim, but now is being added to @dest_wim. If there is in fact already a
237 * lookup table entry for this file in the lookup table of the destination WIM
238 * file, we simply increment its reference count. Otherwise, a new lookup table
239 * entry is created that references the location of the file resource in the
240 * source WIM file through the other_wim_fp field of the lookup table entry.
242 static int add_lookup_table_entry_to_dest_wim(struct dentry *dentry, void *arg)
244 WIMStruct *src_wim, *dest_wim;
245 struct lookup_table_entry *src_table_entry;
246 struct lookup_table_entry *dest_table_entry;
248 src_wim = ((struct wim_pair*)arg)->src_wim;
249 dest_wim = ((struct wim_pair*)arg)->dest_wim;
251 if (dentry_is_directory(dentry))
254 src_table_entry = wim_lookup_resource(src_wim, dentry);
255 if (!src_table_entry)
258 dest_table_entry = wim_lookup_resource(dest_wim, dentry);
259 if (dest_table_entry) {
260 dest_table_entry->refcnt++;
262 dest_table_entry = new_lookup_table_entry();
263 if (!dest_table_entry)
264 return WIMLIB_ERR_NOMEM;
265 dest_table_entry->other_wim_fp = src_wim->fp;
266 dest_table_entry->other_wim_ctype =
267 wimlib_get_compression_type(src_wim);
268 dest_table_entry->refcnt = 1;
269 memcpy(&dest_table_entry->resource_entry,
270 &src_table_entry->resource_entry,
271 sizeof(struct resource_entry));
272 memcpy(dest_table_entry->hash, dentry->hash, WIM_HASH_SIZE);
273 lookup_table_insert(dest_wim->lookup_table, dest_table_entry);
279 * Adds an image (given by its dentry tree) to the image metadata array of a WIM
280 * file, adds an entry to the lookup table for the image metadata, updates the
281 * image count in the header, and selects the new image.
283 * Does not update the XML data.
285 * @w: The WIMStruct for the WIM file.
286 * @root_dentry: The root of the directory tree for the image.
288 static int add_new_dentry_tree(WIMStruct *w, struct dentry *root_dentry)
290 struct lookup_table_entry *metadata_lte;
291 struct image_metadata *imd;
292 struct image_metadata *new_imd;
293 struct wim_security_data *sd;
295 DEBUG("Reallocating image metadata array for image_count = %u",
296 w->hdr.image_count + 1);
297 imd = CALLOC((w->hdr.image_count + 1), sizeof(struct image_metadata));
300 ERROR("Failed to allocate memory for new image metadata array");
301 return WIMLIB_ERR_NOMEM;
304 memcpy(imd, w->image_metadata,
305 w->hdr.image_count * sizeof(struct image_metadata));
307 metadata_lte = new_lookup_table_entry();
310 sd = CALLOC(1, sizeof(struct wim_security_data));
312 goto out_free_metadata_lte;
314 sd->total_length = 8;
316 metadata_lte->resource_entry.flags = WIM_RESHDR_FLAG_METADATA;
317 randomize_byte_array(metadata_lte->hash, WIM_HASH_SIZE);
318 lookup_table_insert(w->lookup_table, metadata_lte);
320 w->hdr.image_count++;
322 new_imd = &imd[w->hdr.image_count - 1];
323 new_imd->metadata_lte = metadata_lte;
324 new_imd->modified = true;
325 new_imd->root_dentry = root_dentry;
326 new_imd->security_data = sd;
327 FREE(w->image_metadata);
328 w->image_metadata = imd;
330 /* Change the current image to the new one. */
331 return wimlib_select_image(w, w->hdr.image_count);
332 out_free_metadata_lte:
336 return WIMLIB_ERR_NOMEM;
341 * Copies an image, or all the images, from a WIM file, into another WIM file.
343 WIMLIBAPI int wimlib_export_image(WIMStruct *src_wim,
346 const char *dest_name,
347 const char *dest_description,
353 struct wim_pair wims;
355 if (src_image == WIM_ALL_IMAGES) {
356 if (src_wim->hdr.image_count > 1) {
358 /* multi-image export. */
360 if ((flags & WIMLIB_EXPORT_FLAG_BOOT) &&
361 (src_wim->hdr.boot_idx == 0))
363 /* Specifying the boot flag on a multi-image
364 * source WIM makes the boot index default to
365 * the bootable image in the source WIM. It is
366 * an error if there is no such bootable image.
368 ERROR("Cannot specify `boot' flag when "
369 "exporting multiple images from a WIM "
370 "with no bootable images");
371 return WIMLIB_ERR_INVALID_PARAM;
373 if (dest_name || dest_description) {
374 ERROR("Image name or image description was "
375 "specified, but we are exporting "
377 return WIMLIB_ERR_INVALID_PARAM;
379 for (i = 1; i <= src_wim->hdr.image_count; i++) {
380 int export_flags = flags;
382 if (i != src_wim->hdr.boot_idx)
383 export_flags &= ~WIMLIB_EXPORT_FLAG_BOOT;
385 ret = wimlib_export_image(src_wim, i, dest_wim,
398 ret = wimlib_select_image(src_wim, src_image);
400 ERROR("Could not select image %d from the WIM `%s' "
401 "to export it", src_image, src_wim->filename);
406 dest_name = wimlib_get_image_name(src_wim, src_image);
407 DEBUG("Using name `%s' for source image %d",
408 dest_name, src_image);
411 DEBUG("Exporting image %d from `%s'", src_image, src_wim->filename);
413 if (wimlib_image_name_in_use(dest_wim, dest_name)) {
414 ERROR("There is already an image named `%s' in the "
415 "destination WIM", dest_name);
416 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
420 /* Cleaning up here on failure would be hard. For example, we could
421 * fail to allocate memory in add_lookup_table_entry_to_dest_wim(),
422 * leaving the lookup table entries in the destination WIM in an
423 * inconsistent state. Until these issues can be resolved,
424 * wimlib_export_image() is documented as leaving dest_wim is an
425 * indeterminate state. */
426 root = wim_root_dentry(src_wim);
427 for_dentry_in_tree(root, increment_dentry_refcnt, NULL);
428 wims.src_wim = src_wim;
429 wims.dest_wim = dest_wim;
430 ret = for_dentry_in_tree(root, add_lookup_table_entry_to_dest_wim, &wims);
433 ret = add_new_dentry_tree(dest_wim, root);
436 /* Bring over old security data */
437 struct wim_security_data *sd = wim_security_data(src_wim);
438 struct image_metadata *new_imd = wim_get_current_image_metadata(dest_wim);
440 free_security_data(new_imd->security_data);
441 new_imd->security_data = sd;
444 if (flags & WIMLIB_EXPORT_FLAG_BOOT) {
445 DEBUG("Setting boot_idx to %d", dest_wim->hdr.image_count);
446 dest_wim->hdr.boot_idx = dest_wim->hdr.image_count;
449 return xml_export_image(src_wim->wim_info, src_image, &dest_wim->wim_info,
450 dest_name, dest_description);
454 * Deletes an image from the WIM.
456 WIMLIBAPI int wimlib_delete_image(WIMStruct *w, int image)
462 if (image == WIM_ALL_IMAGES) {
463 num_images = w->hdr.image_count;
464 for (i = 1; i <= num_images; i++) {
465 /* Always delete the first image, since by the end
466 * there won't be any more than that! */
467 ret = wimlib_delete_image(w, 1);
474 DEBUG("Deleting image %d", image);
476 /* Even if the dentry tree is not allocated, we must select it (and
477 * therefore allocate it) so that we can decrement the reference counts
478 * in the lookup table. */
479 ret = wimlib_select_image(w, image);
483 /* Free the dentry tree, any lookup table entries that have their
484 * refcnt decremented to 0, and the security data. */
485 destroy_image_metadata(wim_get_current_image_metadata(w),
488 /* Get rid of the empty slot in the image metadata array. */
489 memmove(&w->image_metadata[image - 1], &w->image_metadata[image],
490 (w->hdr.image_count - image) * sizeof(struct image_metadata));
492 /* Decrement the image count. */
493 if (--w->hdr.image_count == 0) {
494 FREE(w->image_metadata);
495 w->image_metadata = NULL;
498 /* Fix the boot index. */
499 if (w->hdr.boot_idx == image)
501 else if (w->hdr.boot_idx > image)
504 w->current_image = WIM_NO_IMAGE;
506 /* Remove the image from the XML information. */
507 xml_delete_image(&w->wim_info, image);
512 * Adds an image to a WIM file from a directory tree on disk.
514 WIMLIBAPI int wimlib_add_image(WIMStruct *w, const char *dir,
515 const char *name, const char *description,
516 const char *flags_element, int flags)
518 struct dentry *root_dentry;
519 struct stat root_stat;
520 struct image_metadata *imd;
523 DEBUG("Adding dentry tree from dir `%s'.", dir);
525 if (!name || !*name) {
526 ERROR("Must specify a non-empty string for the image name");
527 return WIMLIB_ERR_INVALID_PARAM;
530 ERROR("Must specify the name of a directory");
531 return WIMLIB_ERR_INVALID_PARAM;
534 if (wimlib_image_name_in_use(w, name)) {
535 ERROR("There is already an image named \"%s\" in `%s'",
537 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
540 DEBUG("Creating root dentry.");
542 root_dentry = new_dentry("");
544 return WIMLIB_ERR_NOMEM;
545 ret = calculate_dentry_full_path(root_dentry, NULL);
548 goto out_free_dentry_tree;
550 root_dentry->attributes |= FILE_ATTRIBUTE_DIRECTORY;
552 DEBUG("Building dentry tree.");
553 ret = build_dentry_tree(root_dentry, dir, w->lookup_table,
554 flags | WIMLIB_ADD_IMAGE_FLAG_ROOT);
557 ERROR("Failed to build dentry tree for `%s'", dir);
558 goto out_free_dentry_tree;
561 DEBUG("Recalculating full paths of dentries.");
562 ret = for_dentry_in_tree(root_dentry, calculate_dentry_full_path, NULL);
564 goto out_free_dentry_tree;
566 ret = add_new_dentry_tree(w, root_dentry);
568 goto out_free_dentry_tree;
570 if (flags & WIMLIB_ADD_IMAGE_FLAG_BOOT)
571 wimlib_set_boot_idx(w, w->hdr.image_count);
573 ret = xml_add_image(w, root_dentry, name, description, flags_element);
575 goto out_destroy_imd;
579 destroy_image_metadata(&w->image_metadata[w->hdr.image_count - 1],
582 out_free_dentry_tree:
583 free_dentry_tree(root_dentry, w->lookup_table, true);