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 void destroy_image_metadata(struct image_metadata *imd,struct lookup_table *lt)
47 free_dentry_tree(imd->root_dentry, lt);
48 free_security_data(imd->security_data);
49 free_link_group_table(imd->lgt);
51 /* Get rid of the lookup table entry for this image's metadata resource
54 lookup_table_remove(lt, imd->metadata_lte);
58 * Recursively builds a dentry tree from a directory tree on disk, outside the
61 * @root: A dentry that has already been created for the root of the dentry
63 * @root_disk_path: The path to the root of the tree on disk.
64 * @lookup_table: The lookup table for the WIM file. For each file added to the
65 * dentry tree being built, an entry is added to the lookup table,
66 * unless an identical file is already in the lookup table. These
67 * lookup table entries that are added point to the file on disk.
69 * @return: 0 on success, nonzero on failure. It is a failure if any of
70 * the files cannot be `stat'ed, or if any of the needed
71 * directories cannot be opened or read. Failure to add the files
72 * to the WIM may still occur later when trying to actually read
73 * the regular files in the tree into the WIM as file resources.
75 static int build_dentry_tree(struct dentry *root, const char *root_disk_path,
76 struct lookup_table* lookup_table,
79 DEBUG("%s", root_disk_path);
80 struct stat root_stbuf;
82 int (*stat_fn)(const char *restrict, struct stat *restrict);
84 if (add_flags & WIMLIB_ADD_IMAGE_FLAG_DEREFERENCE)
90 ret = (*stat_fn)(root_disk_path, &root_stbuf);
92 ERROR_WITH_ERRNO("Failed to stat `%s'", root_disk_path);
93 return WIMLIB_ERR_STAT;
96 if ((add_flags & WIMLIB_ADD_IMAGE_FLAG_ROOT) &&
97 !S_ISDIR(root_stbuf.st_mode)) {
98 ERROR("`%s' is not a directory", root_disk_path);
99 return WIMLIB_ERR_NOTDIR;
101 stbuf_to_dentry(&root_stbuf, root);
102 add_flags &= ~WIMLIB_ADD_IMAGE_FLAG_ROOT;
104 if (dentry_is_directory(root)) {
105 /* Open the directory on disk */
108 struct dentry *child;
110 dir = opendir(root_disk_path);
112 ERROR_WITH_ERRNO("Failed to open the directory `%s'",
114 return WIMLIB_ERR_OPEN;
117 /* Buffer for names of files in directory. */
118 size_t len = strlen(root_disk_path);
119 char name[len + 1 + FILENAME_MAX + 1];
120 memcpy(name, root_disk_path, len);
123 /* Create a dentry for each entry in the directory on disk, and recurse
124 * to any subdirectories. */
125 while ((p = readdir(dir)) != NULL) {
126 if (p->d_name[0] == '.' && (p->d_name[1] == '\0'
127 || (p->d_name[1] == '.' && p->d_name[2] == '\0')))
129 strcpy(name + len + 1, p->d_name);
130 child = new_dentry(p->d_name);
132 return WIMLIB_ERR_NOMEM;
133 ret = build_dentry_tree(child, name, lookup_table,
135 link_dentry(child, root);
140 } else if (dentry_is_symlink(root)) {
141 /* Archiving a symbolic link */
142 size_t symlink_buf_len;
143 char deref_name_buf[4096];
144 ssize_t ret = readlink(root_disk_path, deref_name_buf,
145 sizeof(deref_name_buf) - 1);
147 ERROR_WITH_ERRNO("Failed to read target of "
148 "symbolic link `%s'", root_disk_path);
149 return WIMLIB_ERR_STAT;
151 deref_name_buf[ret] = '\0';
152 DEBUG("Read symlink `%s'", deref_name_buf);
153 ret = dentry_set_symlink(root, deref_name_buf,
157 struct lookup_table_entry *lte;
159 /* For each regular file, we must check to see if the file is in
160 * the lookup table already; if it is, we increment its refcnt;
161 * otherwise, we create a new lookup table entry and insert it.
163 ret = sha1sum(root_disk_path, root->hash);
167 lte = __lookup_resource(lookup_table, root->hash);
171 char *file_on_disk = STRDUP(root_disk_path);
173 ERROR("Failed to allocate memory for file path");
174 return WIMLIB_ERR_NOMEM;
176 lte = new_lookup_table_entry();
179 return WIMLIB_ERR_NOMEM;
181 lte->file_on_disk = file_on_disk;
182 lte->resource_entry.original_size = root_stbuf.st_size;
183 lte->resource_entry.size = root_stbuf.st_size;
184 memcpy(lte->hash, root->hash, WIM_HASH_SIZE);
185 lookup_table_insert(lookup_table, lte);
197 * This function takes in a dentry that was previously located only in image(s)
198 * in @src_wim, but now is being added to @dest_wim. If there is in fact already a
199 * lookup table entry for this file in the lookup table of the destination WIM
200 * file, we simply increment its reference count. Otherwise, a new lookup table
201 * entry is created that references the location of the file resource in the
202 * source WIM file through the other_wim_fp field of the lookup table entry.
204 static int add_lookup_table_entry_to_dest_wim(struct dentry *dentry, void *arg)
206 WIMStruct *src_wim, *dest_wim;
207 struct lookup_table_entry *src_table_entry;
208 struct lookup_table_entry *dest_table_entry;
210 src_wim = ((struct wim_pair*)arg)->src_wim;
211 dest_wim = ((struct wim_pair*)arg)->dest_wim;
213 if (dentry_is_directory(dentry))
217 src_table_entry = __lookup_resource(src_wim->lookup_table, dentry->hash);
218 if (!src_table_entry)
222 dest_table_entry = __lookup_resource(dest_wim->lookup_table, dentry->hash);
223 if (dest_table_entry) {
224 dest_table_entry->refcnt++;
226 dest_table_entry = new_lookup_table_entry();
227 if (!dest_table_entry)
228 return WIMLIB_ERR_NOMEM;
229 dest_table_entry->other_wim_fp = src_wim->fp;
230 dest_table_entry->other_wim_ctype =
231 wimlib_get_compression_type(src_wim);
232 dest_table_entry->refcnt = 1;
233 memcpy(&dest_table_entry->resource_entry,
234 &src_table_entry->resource_entry,
235 sizeof(struct resource_entry));
236 memcpy(dest_table_entry->hash, dentry->hash, WIM_HASH_SIZE);
237 lookup_table_insert(dest_wim->lookup_table, dest_table_entry);
243 * Adds an image (given by its dentry tree) to the image metadata array of a WIM
244 * file, adds an entry to the lookup table for the image metadata, updates the
245 * image count in the header, and selects the new image.
247 * Does not update the XML data.
249 * @w: The WIMStruct for the WIM file.
250 * @root_dentry: The root of the directory tree for the image.
252 static int add_new_dentry_tree(WIMStruct *w, struct dentry *root_dentry)
254 struct lookup_table_entry *metadata_lte;
255 struct image_metadata *imd;
256 struct image_metadata *new_imd;
257 struct wim_security_data *sd;
258 struct link_group_table *lgt;
260 DEBUG("Reallocating image metadata array for image_count = %u",
261 w->hdr.image_count + 1);
262 imd = CALLOC((w->hdr.image_count + 1), sizeof(struct image_metadata));
265 ERROR("Failed to allocate memory for new image metadata array");
266 return WIMLIB_ERR_NOMEM;
269 memcpy(imd, w->image_metadata,
270 w->hdr.image_count * sizeof(struct image_metadata));
272 metadata_lte = new_lookup_table_entry();
275 sd = CALLOC(1, sizeof(struct wim_security_data));
277 goto out_free_metadata_lte;
279 sd->total_length = 8;
281 lgt = new_link_group_table(9001);
283 goto out_free_security_data;
285 metadata_lte->resource_entry.flags = WIM_RESHDR_FLAG_METADATA;
286 randomize_byte_array(metadata_lte->hash, WIM_HASH_SIZE);
287 lookup_table_insert(w->lookup_table, metadata_lte);
289 new_imd = &imd[w->hdr.image_count];
291 new_imd->root_dentry = root_dentry;
292 new_imd->metadata_lte = metadata_lte;
293 new_imd->security_data = sd;
295 new_imd->modified = true;
297 FREE(w->image_metadata);
298 w->image_metadata = imd;
299 w->hdr.image_count++;
301 /* Change the current image to the new one. */
302 return wimlib_select_image(w, w->hdr.image_count);
303 out_free_security_data:
305 out_free_metadata_lte:
309 return WIMLIB_ERR_NOMEM;
314 * Copies an image, or all the images, from a WIM file, into another WIM file.
316 WIMLIBAPI int wimlib_export_image(WIMStruct *src_wim,
319 const char *dest_name,
320 const char *dest_description,
326 struct wim_pair wims;
328 if (src_image == WIM_ALL_IMAGES) {
329 if (src_wim->hdr.image_count > 1) {
331 /* multi-image export. */
333 if ((flags & WIMLIB_EXPORT_FLAG_BOOT) &&
334 (src_wim->hdr.boot_idx == 0))
336 /* Specifying the boot flag on a multi-image
337 * source WIM makes the boot index default to
338 * the bootable image in the source WIM. It is
339 * an error if there is no such bootable image.
341 ERROR("Cannot specify `boot' flag when "
342 "exporting multiple images from a WIM "
343 "with no bootable images");
344 return WIMLIB_ERR_INVALID_PARAM;
346 if (dest_name || dest_description) {
347 ERROR("Image name or image description was "
348 "specified, but we are exporting "
350 return WIMLIB_ERR_INVALID_PARAM;
352 for (i = 1; i <= src_wim->hdr.image_count; i++) {
353 int export_flags = flags;
355 if (i != src_wim->hdr.boot_idx)
356 export_flags &= ~WIMLIB_EXPORT_FLAG_BOOT;
358 ret = wimlib_export_image(src_wim, i, dest_wim,
371 ret = wimlib_select_image(src_wim, src_image);
373 ERROR("Could not select image %d from the WIM `%s' "
374 "to export it", src_image, src_wim->filename);
379 dest_name = wimlib_get_image_name(src_wim, src_image);
380 DEBUG("Using name `%s' for source image %d",
381 dest_name, src_image);
384 DEBUG("Exporting image %d from `%s'", src_image, src_wim->filename);
386 if (wimlib_image_name_in_use(dest_wim, dest_name)) {
387 ERROR("There is already an image named `%s' in the "
388 "destination WIM", dest_name);
389 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
393 /* Cleaning up here on failure would be hard. For example, we could
394 * fail to allocate memory in add_lookup_table_entry_to_dest_wim(),
395 * leaving the lookup table entries in the destination WIM in an
396 * inconsistent state. Until these issues can be resolved,
397 * wimlib_export_image() is documented as leaving dest_wim is an
398 * indeterminate state. */
399 root = wim_root_dentry(src_wim);
400 for_dentry_in_tree(root, increment_dentry_refcnt, NULL);
401 wims.src_wim = src_wim;
402 wims.dest_wim = dest_wim;
403 ret = for_dentry_in_tree(root, add_lookup_table_entry_to_dest_wim, &wims);
406 ret = add_new_dentry_tree(dest_wim, root);
409 /* Bring over old security data */
410 struct wim_security_data *sd = wim_security_data(src_wim);
411 struct image_metadata *new_imd = wim_get_current_image_metadata(dest_wim);
413 free_security_data(new_imd->security_data);
414 new_imd->security_data = sd;
417 if (flags & WIMLIB_EXPORT_FLAG_BOOT) {
418 DEBUG("Setting boot_idx to %d", dest_wim->hdr.image_count);
419 dest_wim->hdr.boot_idx = dest_wim->hdr.image_count;
422 return xml_export_image(src_wim->wim_info, src_image, &dest_wim->wim_info,
423 dest_name, dest_description);
427 * Deletes an image from the WIM.
429 WIMLIBAPI int wimlib_delete_image(WIMStruct *w, int image)
435 if (image == WIM_ALL_IMAGES) {
436 num_images = w->hdr.image_count;
437 for (i = 1; i <= num_images; i++) {
438 /* Always delete the first image, since by the end
439 * there won't be any more than that! */
440 ret = wimlib_delete_image(w, 1);
447 DEBUG("Deleting image %d", image);
449 /* Even if the dentry tree is not allocated, we must select it (and
450 * therefore allocate it) so that we can decrement the reference counts
451 * in the lookup table. */
452 ret = wimlib_select_image(w, image);
456 /* Free the dentry tree, any lookup table entries that have their
457 * refcnt decremented to 0, and the security data. */
458 destroy_image_metadata(wim_get_current_image_metadata(w),
461 /* Get rid of the empty slot in the image metadata array. */
462 memmove(&w->image_metadata[image - 1], &w->image_metadata[image],
463 (w->hdr.image_count - image) * sizeof(struct image_metadata));
465 /* Decrement the image count. */
466 if (--w->hdr.image_count == 0) {
467 FREE(w->image_metadata);
468 w->image_metadata = NULL;
471 /* Fix the boot index. */
472 if (w->hdr.boot_idx == image)
474 else if (w->hdr.boot_idx > image)
477 w->current_image = WIM_NO_IMAGE;
479 /* Remove the image from the XML information. */
480 xml_delete_image(&w->wim_info, image);
485 * Adds an image to a WIM file from a directory tree on disk.
487 WIMLIBAPI int wimlib_add_image(WIMStruct *w, const char *dir,
488 const char *name, const char *description,
489 const char *flags_element, int flags)
491 struct dentry *root_dentry;
492 struct image_metadata *imd;
495 DEBUG("Adding dentry tree from dir `%s'.", dir);
497 if (!name || !*name) {
498 ERROR("Must specify a non-empty string for the image name");
499 return WIMLIB_ERR_INVALID_PARAM;
502 ERROR("Must specify the name of a directory");
503 return WIMLIB_ERR_INVALID_PARAM;
506 if (wimlib_image_name_in_use(w, name)) {
507 ERROR("There is already an image named \"%s\" in `%s'",
509 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
512 DEBUG("Creating root dentry.");
514 root_dentry = new_dentry("");
516 return WIMLIB_ERR_NOMEM;
517 ret = calculate_dentry_full_path(root_dentry, NULL);
520 goto out_free_dentry_tree;
522 root_dentry->attributes |= FILE_ATTRIBUTE_DIRECTORY;
524 DEBUG("Building dentry tree.");
525 ret = build_dentry_tree(root_dentry, dir, w->lookup_table,
526 flags | WIMLIB_ADD_IMAGE_FLAG_ROOT);
529 ERROR("Failed to build dentry tree for `%s'", dir);
530 goto out_free_dentry_tree;
533 DEBUG("Recalculating full paths of dentries.");
534 ret = for_dentry_in_tree(root_dentry, calculate_dentry_full_path, NULL);
536 goto out_free_dentry_tree;
538 ret = add_new_dentry_tree(w, root_dentry);
540 goto out_free_dentry_tree;
542 DEBUG("Inserting dentries into hard link group table");
543 ret = for_dentry_in_tree(root_dentry, link_group_table_insert,
544 w->image_metadata[w->hdr.image_count - 1].lgt);
546 goto out_destroy_imd;
547 DEBUG("Assigning hard link groups");
548 assign_link_groups(w->image_metadata[w->hdr.image_count - 1].lgt);
550 if (flags & WIMLIB_ADD_IMAGE_FLAG_BOOT)
551 wimlib_set_boot_idx(w, w->hdr.image_count);
553 ret = xml_add_image(w, root_dentry, name, description, flags_element);
555 goto out_destroy_imd;
559 destroy_image_metadata(&w->image_metadata[w->hdr.image_count - 1],
561 w->hdr.image_count--;
563 out_free_dentry_tree:
564 free_dentry_tree(root_dentry, w->lookup_table);