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)
89 if (add_flags & WIMLIB_ADD_IMAGE_FLAG_VERBOSE)
90 printf("Scanning `%s'\n", root_disk_path);
93 ret = (*stat_fn)(root_disk_path, &root_stbuf);
95 ERROR_WITH_ERRNO("Failed to stat `%s'", root_disk_path);
96 return WIMLIB_ERR_STAT;
99 if ((add_flags & WIMLIB_ADD_IMAGE_FLAG_ROOT) &&
100 !S_ISDIR(root_stbuf.st_mode)) {
101 ERROR("`%s' is not a directory", root_disk_path);
102 return WIMLIB_ERR_NOTDIR;
104 if (!S_ISREG(root_stbuf.st_mode) && !S_ISDIR(root_stbuf.st_mode)
105 && !S_ISLNK(root_stbuf.st_mode)) {
106 ERROR("`%s' is not a regular file, directory, or symbolic link.");
107 return WIMLIB_ERR_SPECIAL_FILE;
109 stbuf_to_dentry(&root_stbuf, root);
110 add_flags &= ~WIMLIB_ADD_IMAGE_FLAG_ROOT;
111 root->resolved = true;
113 if (dentry_is_directory(root)) {
114 /* Open the directory on disk */
117 struct dentry *child;
119 dir = opendir(root_disk_path);
121 ERROR_WITH_ERRNO("Failed to open the directory `%s'",
123 return WIMLIB_ERR_OPEN;
126 /* Buffer for names of files in directory. */
127 size_t len = strlen(root_disk_path);
128 char name[len + 1 + FILENAME_MAX + 1];
129 memcpy(name, root_disk_path, len);
132 /* Create a dentry for each entry in the directory on disk, and recurse
133 * to any subdirectories. */
134 while ((p = readdir(dir)) != NULL) {
135 if (p->d_name[0] == '.' && (p->d_name[1] == '\0'
136 || (p->d_name[1] == '.' && p->d_name[2] == '\0')))
138 strcpy(name + len + 1, p->d_name);
139 child = new_dentry(p->d_name);
141 return WIMLIB_ERR_NOMEM;
142 ret = build_dentry_tree(child, name, lookup_table,
144 link_dentry(child, root);
149 } else if (dentry_is_symlink(root)) {
150 /* Archiving a symbolic link */
151 size_t symlink_buf_len;
152 char deref_name_buf[4096];
153 ssize_t deref_name_len;
155 deref_name_len = readlink(root_disk_path, deref_name_buf,
156 sizeof(deref_name_buf) - 1);
157 if (deref_name_len == -1) {
158 ERROR_WITH_ERRNO("Failed to read target of "
159 "symbolic link `%s'", root_disk_path);
160 return WIMLIB_ERR_READLINK;
162 deref_name_buf[deref_name_len] = '\0';
163 DEBUG("Read symlink `%s'", deref_name_buf);
164 ret = dentry_set_symlink(root, deref_name_buf,
168 struct lookup_table_entry *lte;
169 u8 hash[SHA1_HASH_SIZE];
171 /* For each regular file, we must check to see if the file is in
172 * the lookup table already; if it is, we increment its refcnt;
173 * otherwise, we create a new lookup table entry and insert it.
175 ret = sha1sum(root_disk_path, hash);
179 lte = __lookup_resource(lookup_table, hash);
182 DEBUG("Add lte reference %u for `%s'", lte->refcnt,
185 char *file_on_disk = STRDUP(root_disk_path);
187 ERROR("Failed to allocate memory for file path");
188 return WIMLIB_ERR_NOMEM;
190 lte = new_lookup_table_entry();
193 return WIMLIB_ERR_NOMEM;
195 lte->file_on_disk = file_on_disk;
196 lte->resource_location = RESOURCE_IN_FILE_ON_DISK;
197 lte->resource_entry.original_size = root_stbuf.st_size;
198 lte->resource_entry.size = root_stbuf.st_size;
199 copy_hash(lte->hash, hash);
200 lookup_table_insert(lookup_table, lte);
213 * This function takes in a dentry that was previously located only in image(s)
214 * in @src_wim, but now is being added to @dest_wim. If there is in fact already a
215 * lookup table entry for this file in the lookup table of the destination WIM
216 * file, we simply increment its reference count. Otherwise, a new lookup table
217 * entry is created that references the location of the file resource in the
218 * source WIM file through the other_wim_fp field of the lookup table entry.
220 static int add_lte_to_dest_wim(struct dentry *dentry, void *arg)
222 WIMStruct *src_wim, *dest_wim;
224 src_wim = ((struct wim_pair*)arg)->src_wim;
225 dest_wim = ((struct wim_pair*)arg)->dest_wim;
227 wimlib_assert(!dentry->resolved);
229 for (unsigned i = 0; i < (unsigned)dentry->num_ads + 1; i++) {
230 struct lookup_table_entry *src_lte, *dest_lte;
231 src_lte = dentry_stream_lte_unresolved(dentry, i,
232 src_wim->lookup_table);
235 dest_lte = dentry_stream_lte_unresolved(dentry, i,
236 dest_wim->lookup_table);
240 dest_lte = new_lookup_table_entry();
242 return WIMLIB_ERR_NOMEM;
243 dest_lte->resource_location = RESOURCE_IN_WIM;
244 dest_lte->wim = src_wim;
245 memcpy(&dest_lte->resource_entry,
246 &src_lte->resource_entry,
247 sizeof(struct resource_entry));
248 copy_hash(dest_lte->hash,
249 dentry_stream_hash_unresolved(dentry, i));
250 lookup_table_insert(dest_wim->lookup_table, dest_lte);
257 * Adds an image (given by its dentry tree) to the image metadata array of a WIM
258 * file, adds an entry to the lookup table for the image metadata, updates the
259 * image count in the header, and selects the new image.
261 * Does not update the XML data.
263 * @w: The WIMStruct for the WIM file.
264 * @root_dentry: The root of the directory tree for the image.
266 static int add_new_dentry_tree(WIMStruct *w, struct dentry *root_dentry)
268 struct lookup_table_entry *metadata_lte;
269 struct image_metadata *imd;
270 struct image_metadata *new_imd;
271 struct wim_security_data *sd;
272 struct link_group_table *lgt;
274 DEBUG("Reallocating image metadata array for image_count = %u",
275 w->hdr.image_count + 1);
276 imd = CALLOC((w->hdr.image_count + 1), sizeof(struct image_metadata));
279 ERROR("Failed to allocate memory for new image metadata array");
280 return WIMLIB_ERR_NOMEM;
283 memcpy(imd, w->image_metadata,
284 w->hdr.image_count * sizeof(struct image_metadata));
286 metadata_lte = new_lookup_table_entry();
289 sd = CALLOC(1, sizeof(struct wim_security_data));
291 goto out_free_metadata_lte;
293 sd->total_length = 8;
295 lgt = new_link_group_table(9001);
297 goto out_free_security_data;
299 metadata_lte->resource_entry.flags = WIM_RESHDR_FLAG_METADATA;
300 random_hash(metadata_lte->hash);
301 lookup_table_insert(w->lookup_table, metadata_lte);
303 new_imd = &imd[w->hdr.image_count];
305 new_imd->root_dentry = root_dentry;
306 new_imd->metadata_lte = metadata_lte;
307 new_imd->security_data = sd;
309 new_imd->modified = true;
311 FREE(w->image_metadata);
312 w->image_metadata = imd;
313 w->hdr.image_count++;
315 /* Change the current image to the new one. */
316 return wimlib_select_image(w, w->hdr.image_count);
317 out_free_security_data:
319 out_free_metadata_lte:
323 return WIMLIB_ERR_NOMEM;
328 * Copies an image, or all the images, from a WIM file, into another WIM file.
330 WIMLIBAPI int wimlib_export_image(WIMStruct *src_wim,
333 const char *dest_name,
334 const char *dest_description,
340 struct wim_pair wims;
342 if (src_image == WIM_ALL_IMAGES) {
343 if (src_wim->hdr.image_count > 1) {
345 /* multi-image export. */
347 if ((flags & WIMLIB_EXPORT_FLAG_BOOT) &&
348 (src_wim->hdr.boot_idx == 0))
350 /* Specifying the boot flag on a multi-image
351 * source WIM makes the boot index default to
352 * the bootable image in the source WIM. It is
353 * an error if there is no such bootable image.
355 ERROR("Cannot specify `boot' flag when "
356 "exporting multiple images from a WIM "
357 "with no bootable images");
358 return WIMLIB_ERR_INVALID_PARAM;
360 if (dest_name || dest_description) {
361 ERROR("Image name or image description was "
362 "specified, but we are exporting "
364 return WIMLIB_ERR_INVALID_PARAM;
366 for (i = 1; i <= src_wim->hdr.image_count; i++) {
367 int export_flags = flags;
369 if (i != src_wim->hdr.boot_idx)
370 export_flags &= ~WIMLIB_EXPORT_FLAG_BOOT;
372 ret = wimlib_export_image(src_wim, i, dest_wim,
385 ret = wimlib_select_image(src_wim, src_image);
387 ERROR("Could not select image %d from the WIM `%s' "
388 "to export it", src_image, src_wim->filename);
393 dest_name = wimlib_get_image_name(src_wim, src_image);
394 DEBUG("Using name `%s' for source image %d",
395 dest_name, src_image);
398 DEBUG("Exporting image %d from `%s'", src_image, src_wim->filename);
400 if (wimlib_image_name_in_use(dest_wim, dest_name)) {
401 ERROR("There is already an image named `%s' in the "
402 "destination WIM", dest_name);
403 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
407 /* Cleaning up here on failure would be hard. For example, we could
408 * fail to allocate memory in add_lte_to_dest_wim(),
409 * leaving the lookup table entries in the destination WIM in an
410 * inconsistent state. Until these issues can be resolved,
411 * wimlib_export_image() is documented as leaving dest_wim is an
412 * indeterminate state. */
413 root = wim_root_dentry(src_wim);
414 for_dentry_in_tree(root, increment_dentry_refcnt, NULL);
415 wims.src_wim = src_wim;
416 wims.dest_wim = dest_wim;
417 ret = for_dentry_in_tree(root, add_lte_to_dest_wim, &wims);
420 ret = add_new_dentry_tree(dest_wim, root);
423 /* Bring over old security data */
424 struct wim_security_data *sd = wim_security_data(src_wim);
425 struct image_metadata *new_imd = wim_get_current_image_metadata(dest_wim);
427 free_security_data(new_imd->security_data);
428 new_imd->security_data = sd;
431 if (flags & WIMLIB_EXPORT_FLAG_BOOT) {
432 DEBUG("Setting boot_idx to %d", dest_wim->hdr.image_count);
433 dest_wim->hdr.boot_idx = dest_wim->hdr.image_count;
436 return xml_export_image(src_wim->wim_info, src_image, &dest_wim->wim_info,
437 dest_name, dest_description);
441 * Deletes an image from the WIM.
443 WIMLIBAPI int wimlib_delete_image(WIMStruct *w, int image)
449 if (image == WIM_ALL_IMAGES) {
450 num_images = w->hdr.image_count;
451 for (i = 1; i <= num_images; i++) {
452 /* Always delete the first image, since by the end
453 * there won't be any more than that! */
454 ret = wimlib_delete_image(w, 1);
461 DEBUG("Deleting image %d", image);
463 /* Even if the dentry tree is not allocated, we must select it (and
464 * therefore allocate it) so that we can decrement the reference counts
465 * in the lookup table. */
466 ret = wimlib_select_image(w, image);
470 /* Free the dentry tree, any lookup table entries that have their
471 * refcnt decremented to 0, and the security data. */
472 destroy_image_metadata(wim_get_current_image_metadata(w),
475 /* Get rid of the empty slot in the image metadata array. */
476 memmove(&w->image_metadata[image - 1], &w->image_metadata[image],
477 (w->hdr.image_count - image) * sizeof(struct image_metadata));
479 /* Decrement the image count. */
480 if (--w->hdr.image_count == 0) {
481 FREE(w->image_metadata);
482 w->image_metadata = NULL;
485 /* Fix the boot index. */
486 if (w->hdr.boot_idx == image)
488 else if (w->hdr.boot_idx > image)
491 w->current_image = WIM_NO_IMAGE;
493 /* Remove the image from the XML information. */
494 xml_delete_image(&w->wim_info, image);
499 * Adds an image to a WIM file from a directory tree on disk.
501 WIMLIBAPI int wimlib_add_image(WIMStruct *w, const char *dir,
502 const char *name, const char *description,
503 const char *flags_element, int flags)
505 struct dentry *root_dentry;
506 struct image_metadata *imd;
509 DEBUG("Adding dentry tree from dir `%s'.", dir);
511 if (!name || !*name) {
512 ERROR("Must specify a non-empty string for the image name");
513 return WIMLIB_ERR_INVALID_PARAM;
516 ERROR("Must specify the name of a directory");
517 return WIMLIB_ERR_INVALID_PARAM;
520 if (wimlib_image_name_in_use(w, name)) {
521 ERROR("There is already an image named \"%s\" in `%s'",
523 return WIMLIB_ERR_IMAGE_NAME_COLLISION;
526 DEBUG("Creating root dentry.");
528 root_dentry = new_dentry("");
530 return WIMLIB_ERR_NOMEM;
532 DEBUG("Building dentry tree.");
533 ret = build_dentry_tree(root_dentry, dir, w->lookup_table,
534 flags | WIMLIB_ADD_IMAGE_FLAG_ROOT);
537 ERROR("Failed to build dentry tree for `%s'", dir);
538 goto out_free_dentry_tree;
541 DEBUG("Calculating full paths of dentries.");
542 ret = for_dentry_in_tree(root_dentry, calculate_dentry_full_path, NULL);
544 goto out_free_dentry_tree;
546 ret = add_new_dentry_tree(w, root_dentry);
548 goto out_free_dentry_tree;
550 DEBUG("Inserting dentries into hard link group table");
551 ret = for_dentry_in_tree(root_dentry, link_group_table_insert,
552 w->image_metadata[w->hdr.image_count - 1].lgt);
554 goto out_destroy_imd;
555 DEBUG("Assigning hard link groups");
556 assign_link_groups(w->image_metadata[w->hdr.image_count - 1].lgt);
558 if (flags & WIMLIB_ADD_IMAGE_FLAG_BOOT)
559 wimlib_set_boot_idx(w, w->hdr.image_count);
561 ret = xml_add_image(w, root_dentry, name, description, flags_element);
563 goto out_destroy_imd;
567 destroy_image_metadata(&w->image_metadata[w->hdr.image_count - 1],
569 w->hdr.image_count--;
571 out_free_dentry_tree:
572 free_dentry_tree(root_dentry, w->lookup_table);