4 * Support for extracting WIM files.
8 * Copyright (C) 2010 Carl Thijssen
9 * Copyright (C) 2012 Eric Biggers
11 * This file is part of wimlib, a library for working with WIM files.
13 * wimlib is free software; you can redistribute it and/or modify it under the
14 * terms of the GNU Lesser General Public License as published by the Free
15 * Software Foundation; either version 2.1 of the License, or (at your option)
18 * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
19 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
20 * A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
23 * You should have received a copy of the GNU Lesser General Public License
24 * along with wimlib; if not, see http://www.gnu.org/licenses/.
27 #include "wimlib_internal.h"
29 #include "lookup_table.h"
39 #include <ntfs-3g/volume.h>
42 /* Sets and creates the directory to which files are to be extracted when
43 * extracting files from the WIM. */
44 static int set_output_dir(WIMStruct *w, const char *dir)
47 DEBUG("Setting output directory to `%s'", dir);
51 ERROR("Out of memory");
52 return WIMLIB_ERR_NOMEM;
55 if (mkdir(dir, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) != 0) {
56 if (errno == EEXIST) {
57 DEBUG("`%s' already exists", dir);
60 ERROR_WITH_ERRNO("Cannot create directory `%s'", dir);
62 return WIMLIB_ERR_MKDIR;
64 DEBUG("Created directory `%s'", dir);
73 * Extracts a regular file from the WIM archive.
75 * @dentry: The directory entry for the file, which must be a
77 * @output_path: The path to which the file is to be extracted.
78 * @lookup_table: The lookup table for the WIM file.
79 * @wim_fp: The FILE* for the WIM, opened for reading.
80 * @wim_ctype: The type of compression used in the WIM.
81 * @link_type: One of WIM_LINK_TYPE_*; specifies what to do with
82 * files that are hard-linked inside the WIM.
83 * @is_multi_image_extraction:
84 * True if the image currently being extracted is just one
85 * image of a multi-image extraction. This is needed so
86 * that cross-image symbolic links can be created
89 static int extract_regular_file(WIMStruct *w,
90 const struct dentry *dentry,
91 const char *output_path)
93 struct lookup_table_entry *lte;
96 const struct resource_entry *res_entry;
98 lte = lookup_resource(w->lookup_table, dentry->hash);
100 /* If we already extracted the same file or a hard link copy of it, we
101 * may be able to simply create a link. The exact action is specified
102 * by the current @link_type. */
103 if ((w->extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK)) &&
104 lte && lte->out_refcnt != 0)
106 wimlib_assert(lte->file_on_disk);
108 if (w->extract_flags & WIMLIB_EXTRACT_FLAG_HARDLINK) {
109 if (link(lte->file_on_disk, output_path) != 0) {
110 ERROR_WITH_ERRNO("Failed to hard link "
112 output_path, lte->file_on_disk);
113 return WIMLIB_ERR_LINK;
116 int num_path_components;
117 int num_output_dir_path_components;
118 size_t file_on_disk_len;
123 num_path_components =
124 get_num_path_components(dentry->full_path_utf8) - 1;
125 num_output_dir_path_components =
126 get_num_path_components(w->output_dir);
128 if (w->is_multi_image_extraction) {
129 num_path_components++;
130 num_output_dir_path_components--;
132 file_on_disk_len = strlen(lte->file_on_disk);
134 char buf[file_on_disk_len + 3 * num_path_components + 1];
137 for (i = 0; i < num_path_components; i++) {
142 p2 = lte->file_on_disk;
145 while (num_output_dir_path_components--)
146 p2 = path_next_part(p2, NULL);
148 if (symlink(buf, output_path) != 0) {
149 ERROR_WITH_ERRNO("Failed to symlink `%s' to "
151 buf, lte->file_on_disk);
152 return WIMLIB_ERR_LINK;
159 /* Otherwise, we must actually extract the file contents. */
161 out_fd = open(output_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
163 ERROR_WITH_ERRNO("Failed to open the file `%s' for writing",
165 return WIMLIB_ERR_OPEN;
168 /* Extract empty file, with no lookup table entry... */
170 DEBUG("Empty file `%s'.", output_path);
175 res_entry = <e->resource_entry;
177 ret = extract_resource_to_fd(w, res_entry, out_fd,
178 res_entry->original_size);
181 ERROR("Failed to extract resource to `%s'", output_path);
185 /* Mark the lookup table entry to indicate this file has been extracted. */
187 FREE(lte->file_on_disk);
188 lte->file_on_disk = STRDUP(output_path);
189 if (lte->file_on_disk)
192 ret = WIMLIB_ERR_NOMEM;
199 * Extracts a directory from the WIM archive.
201 * @dentry: The directory entry for the directory.
202 * @output_path: The path to which the directory is to be extracted to.
203 * @return: True on success, false on failure.
205 static int extract_directory(struct dentry *dentry, const char *output_path)
207 /* Compute the output path directory to the directory. */
208 if (mkdir(output_path, S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH) != 0)
211 case EEXIST: /* Already existing directory is OK */
212 case EACCES: /* We may have permissions to extract files inside
213 the directory, but not for the directory
217 ERROR_WITH_ERRNO("Cannot create directory `%s'",
219 return WIMLIB_ERR_MKDIR;
227 * Extracts a file or directory from the WIM archive. For use in
228 * for_dentry_in_tree().
230 * @dentry: The dentry to extract.
231 * @arg: A pointer to the WIMStruct for the WIM file.
233 static int extract_regular_file_or_directory(struct dentry *dentry, void *arg)
235 WIMStruct *w = (WIMStruct*)arg;
236 size_t len = strlen(w->output_dir);
237 char output_path[len + dentry->full_path_utf8_len + 1];
239 if (w->extract_flags & WIMLIB_EXTRACT_FLAG_VERBOSE)
240 puts(dentry->full_path_utf8);
242 memcpy(output_path, w->output_dir, len);
243 memcpy(output_path + len, dentry->full_path_utf8, dentry->full_path_utf8_len);
244 output_path[len + dentry->full_path_utf8_len] = '\0';
246 if (dentry_is_regular_file(dentry)) {
247 return extract_regular_file(w, dentry, output_path);
249 if (dentry_is_root(dentry)) /* Root doesn't need to be extracted. */
252 return extract_directory(dentry, output_path);
256 static int extract_single_image(WIMStruct *w, int image)
258 DEBUG("Extracting image %d", image);
261 ret = wimlib_select_image(w, image);
265 return for_dentry_in_tree(wim_root_dentry(w),
266 extract_regular_file_or_directory, w);
270 /* Extracts all images from the WIM to w->output_dir, with the images placed in
271 * subdirectories named by their image names. */
272 static int extract_all_images(WIMStruct *w)
274 size_t image_name_max_len = max(xml_get_max_image_name_len(w), 20);
275 size_t output_path_len = strlen(w->output_dir);
276 char buf[output_path_len + 1 + image_name_max_len + 1];
279 const char *image_name;
281 DEBUG("Attempting to extract all images from `%s'", w->filename);
283 memcpy(buf, w->output_dir, output_path_len);
284 buf[output_path_len] = '/';
285 for (image = 1; image <= w->hdr.image_count; image++) {
287 image_name = wimlib_get_image_name(w, image);
289 strcpy(buf + output_path_len + 1, image_name);
291 /* Image name is empty. Use image number instead */
292 sprintf(buf + output_path_len + 1, "%d", image);
294 ret = set_output_dir(w, buf);
297 ret = extract_single_image(w, image);
302 /* Restore original output directory */
303 buf[output_path_len + 1] = '\0';
307 /* Extracts a single image or all images from a WIM file. */
308 WIMLIBAPI int wimlib_extract_image(WIMStruct *w, int image,
309 const char *output_dir, int flags)
313 return WIMLIB_ERR_INVALID_PARAM;
314 if ((flags & (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))
315 == (WIMLIB_EXTRACT_FLAG_SYMLINK | WIMLIB_EXTRACT_FLAG_HARDLINK))
316 return WIMLIB_ERR_INVALID_PARAM;
318 ret = set_output_dir(w, output_dir);
322 if ((flags & WIMLIB_EXTRACT_FLAG_NTFS)) {
324 unsigned long mnt_flags;
325 ret = ntfs_check_if_mounted(output_dir, &mnt_flags);
327 ERROR_WITH_ERRNO("NTFS-3g: Cannot determine if `%s' "
328 "is mounted", output_dir);
329 return WIMLIB_ERR_NTFS_3G;
331 if (!(mnt_flags & NTFS_MF_MOUNTED)) {
332 ERROR("NTFS-3g: Filesystem on `%s' is not mounted ",
335 if (mnt_flags & NTFS_MF_READONLY) {
336 ERROR("NTFS-3g: Filesystem on `%s' is mounted "
337 "read-only", output_dir);
338 return WIMLIB_ERR_NTFS_3G;
341 ERROR("wimlib was compiled without support for NTFS-3g, so");
342 ERROR("we cannot extract a WIM image while preserving NTFS-");
343 ERROR("specific information");
344 return WIMLIB_ERR_UNSUPPORTED;
347 w->extract_flags = flags;
348 if (image == WIM_ALL_IMAGES) {
349 w->is_multi_image_extraction = true;
350 ret = extract_all_images(w);
352 w->is_multi_image_extraction = false;
353 ret = extract_single_image(w, image);