resource.c: Cleanup and refactor
[wimlib] / src / extract.c
1 /*
2  * extract.c
3  *
4  * Support for extracting WIM images, or files or directories contained in a WIM
5  * image.
6  */
7
8 /*
9  * Copyright (C) 2012, 2013 Eric Biggers
10  *
11  * This file is part of wimlib, a library for working with WIM files.
12  *
13  * wimlib is free software; you can redistribute it and/or modify it under the
14  * terms of the GNU General Public License as published by the Free
15  * Software Foundation; either version 3 of the License, or (at your option)
16  * any later version.
17  *
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 General Public License for more
21  * details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with wimlib; if not, see http://www.gnu.org/licenses/.
25  */
26
27 /*
28  * This file provides the API functions wimlib_extract_image(),
29  * wimlib_extract_files(), and wimlib_extract_image_from_pipe().  Internally,
30  * all end up calling extract_tree() zero or more times to extract a tree of
31  * files from the currently selected WIM image to the specified target directory
32  * or NTFS volume.
33  *
34  * Although wimlib supports multiple extraction modes/backends (NTFS-3g, UNIX,
35  * Win32), this file does not itself have code to extract files or directories
36  * to any specific target; instead, it handles generic functionality and relies
37  * on lower-level callback functions declared in `struct apply_operations' to do
38  * the actual extraction.
39  */
40
41 #ifdef HAVE_CONFIG_H
42 #  include "config.h"
43 #endif
44
45 #include "wimlib/apply.h"
46 #include "wimlib/dentry.h"
47 #include "wimlib/encoding.h"
48 #include "wimlib/endianness.h"
49 #include "wimlib/error.h"
50 #include "wimlib/lookup_table.h"
51 #include "wimlib/metadata.h"
52 #include "wimlib/paths.h"
53 #include "wimlib/reparse.h"
54 #include "wimlib/resource.h"
55 #include "wimlib/security.h"
56 #ifdef __WIN32__
57 #  include "wimlib/win32.h" /* for realpath() equivalent */
58 #endif
59 #include "wimlib/xml.h"
60 #include "wimlib/wim.h"
61
62 #include <errno.h>
63 #include <fcntl.h>
64 #include <stdlib.h>
65 #include <sys/stat.h>
66 #include <unistd.h>
67
68 #define WIMLIB_EXTRACT_FLAG_MULTI_IMAGE 0x80000000
69 #define WIMLIB_EXTRACT_FLAG_FROM_PIPE   0x40000000
70 #define WIMLIB_EXTRACT_MASK_PUBLIC      0x3fffffff
71
72 /* Given a WIM dentry in the tree to be extracted, resolve all streams in the
73  * corresponding inode and set 'out_refcnt' in each to 0.  */
74 static int
75 dentry_resolve_and_zero_lte_refcnt(struct wim_dentry *dentry, void *_ctx)
76 {
77         struct apply_ctx *ctx = _ctx;
78         struct wim_inode *inode = dentry->d_inode;
79         struct wim_lookup_table_entry *lte;
80         int ret;
81         bool force = false;
82
83         if (dentry->extraction_skipped)
84                 return 0;
85
86         /* Special case:  when extracting from a pipe, the WIM lookup table is
87          * initially empty, so "resolving" an inode's streams is initially not
88          * possible.  However, we still need to keep track of which streams,
89          * identified by SHA1 message digests, need to be extracted, so we
90          * "resolve" the inode's streams anyway by allocating new entries.  */
91         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE)
92                 force = true;
93         ret = inode_resolve_ltes(inode, ctx->wim->lookup_table, force);
94         if (ret)
95                 return ret;
96         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
97                 lte = inode_stream_lte_resolved(inode, i);
98                 if (lte)
99                         lte->out_refcnt = 0;
100         }
101         return 0;
102 }
103
104 static inline bool
105 is_linked_extraction(const struct apply_ctx *ctx)
106 {
107         return 0 != (ctx->extract_flags & (WIMLIB_EXTRACT_FLAG_HARDLINK |
108                                            WIMLIB_EXTRACT_FLAG_SYMLINK));
109 }
110
111 static inline bool
112 can_extract_named_data_streams(const struct apply_ctx *ctx)
113 {
114         return ctx->supported_features.named_data_streams &&
115                 !is_linked_extraction(ctx);
116 }
117
118 static int
119 ref_stream_to_extract(struct wim_lookup_table_entry *lte,
120                       struct wim_dentry *dentry, struct apply_ctx *ctx)
121 {
122         if (!lte)
123                 return 0;
124
125         /* Tally the size only for each extraction of the stream (not hard
126          * links).  */
127         if (!(dentry->d_inode->i_visited &&
128               ctx->supported_features.hard_links) &&
129             (!is_linked_extraction(ctx) || (lte->out_refcnt == 0 &&
130                                             lte->extracted_file == NULL)))
131         {
132                 ctx->progress.extract.total_bytes += wim_resource_size(lte);
133                 ctx->progress.extract.num_streams++;
134         }
135
136         /* Add stream to the extraction_list only one time, even if it's going
137          * to be extracted to multiple locations.  */
138         if (lte->out_refcnt == 0) {
139                 list_add_tail(&lte->extraction_list, &ctx->stream_list);
140                 ctx->num_streams_remaining++;
141         }
142
143         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_SEQUENTIAL) {
144                 struct wim_dentry **lte_dentries;
145
146                 /* Append dentry to this stream's array of dentries referencing
147                  * it.  Use inline array to avoid memory allocation until the
148                  * number of dentries becomes too large.  */
149                 if (lte->out_refcnt < ARRAY_LEN(lte->inline_lte_dentries)) {
150                         lte_dentries = lte->inline_lte_dentries;
151                 } else {
152                         struct wim_dentry **prev_lte_dentries;
153                         size_t alloc_lte_dentries;
154
155                         if (lte->out_refcnt == ARRAY_LEN(lte->inline_lte_dentries)) {
156                                 prev_lte_dentries = NULL;
157                                 alloc_lte_dentries = ARRAY_LEN(lte->inline_lte_dentries);
158                         } else {
159                                 prev_lte_dentries = lte->lte_dentries;
160                                 alloc_lte_dentries = lte->alloc_lte_dentries;
161                         }
162
163                         if (lte->out_refcnt == alloc_lte_dentries) {
164                                 alloc_lte_dentries *= 2;
165                                 lte_dentries = REALLOC(prev_lte_dentries,
166                                                        alloc_lte_dentries *
167                                                         sizeof(lte_dentries[0]));
168                                 if (!lte_dentries)
169                                         return WIMLIB_ERR_NOMEM;
170                                 if (prev_lte_dentries == NULL) {
171                                         memcpy(lte_dentries,
172                                                lte->inline_lte_dentries,
173                                                sizeof(lte->inline_lte_dentries));
174                                 }
175                                 lte->lte_dentries = lte_dentries;
176                                 lte->alloc_lte_dentries = alloc_lte_dentries;
177                         }
178                         lte_dentries = lte->lte_dentries;
179                 }
180                 lte_dentries[lte->out_refcnt] = dentry;
181         }
182         lte->out_refcnt++;
183         return 0;
184 }
185
186 /* Given a WIM dentry in the tree to be extracted, iterate through streams that
187  * need to be extracted.  For each one, add it to the list of streams to be
188  * extracted (ctx->stream_list) if not already done so, and also update the
189  * progress information (ctx->progress) with the stream.  Furthermore, if doing
190  * a sequential extraction, build a mapping from each the stream to the dentries
191  * referencing it.
192  *
193  * This uses the i_visited member of the inodes (assumed to be 0 initially).  */
194 static int
195 dentry_add_streams_to_extract(struct wim_dentry *dentry, void *_ctx)
196 {
197         struct apply_ctx *ctx = _ctx;
198         struct wim_inode *inode = dentry->d_inode;
199         int ret;
200
201         /* Don't process dentries marked as skipped.  */
202         if (dentry->extraction_skipped)
203                 return 0;
204
205         /* The unnamed data stream will always be extracted, except in an
206          * unlikely case.  */
207         if (!inode_is_encrypted_directory(inode)) {
208                 ret = ref_stream_to_extract(inode_unnamed_lte_resolved(inode),
209                                             dentry, ctx);
210                 if (ret)
211                         return ret;
212         }
213
214         /* Named data streams will be extracted only if supported in the current
215          * extraction mode and volume, and to avoid complications, if not doing
216          * a linked extraction.  */
217         if (can_extract_named_data_streams(ctx)) {
218                 for (u16 i = 0; i < inode->i_num_ads; i++) {
219                         if (!ads_entry_is_named_stream(&inode->i_ads_entries[i]))
220                                 continue;
221                         ret = ref_stream_to_extract(inode->i_ads_entries[i].lte,
222                                                     dentry, ctx);
223                         if (ret)
224                                 return ret;
225                 }
226         }
227         inode->i_visited = 1;
228         return 0;
229 }
230
231 /* Inform library user of progress of stream extraction following the successful
232  * extraction of a copy of the stream specified by @lte.  */
233 static void
234 update_extract_progress(struct apply_ctx *ctx,
235                         const struct wim_lookup_table_entry *lte)
236 {
237         wimlib_progress_func_t progress_func = ctx->progress_func;
238         union wimlib_progress_info *progress = &ctx->progress;
239
240         progress->extract.completed_bytes += wim_resource_size(lte);
241         if (progress_func &&
242             progress->extract.completed_bytes >= ctx->next_progress)
243         {
244                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS, progress);
245                 if (progress->extract.completed_bytes >=
246                     progress->extract.total_bytes)
247                 {
248                         ctx->next_progress = ~0ULL;
249                 } else {
250                         ctx->next_progress += progress->extract.total_bytes / 128;
251                         if (ctx->next_progress > progress->extract.total_bytes)
252                                 ctx->next_progress = progress->extract.total_bytes;
253                 }
254         }
255 }
256
257 #ifndef __WIN32__
258 /* Extract a symbolic link (not directly as reparse data), handling fixing up
259  * the target of absolute symbolic links and updating the extract progress.
260  *
261  * @inode must specify the WIM inode for a symbolic link or junction reparse
262  * point.
263  *
264  * @lte_override overrides the resource used as the reparse data for the
265  * symbolic link.  */
266 static int
267 extract_symlink(const tchar *path, struct apply_ctx *ctx,
268                 struct wim_inode *inode,
269                 struct wim_lookup_table_entry *lte_override)
270 {
271         ssize_t bufsize = ctx->ops->path_max;
272         tchar target[bufsize];
273         tchar *buf = target;
274         tchar *fixed_target;
275         ssize_t sret;
276         int ret;
277
278         /* If absolute symbolic link fixups requested, reserve space in the link
279          * target buffer for the absolute path of the target directory.  */
280         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX)
281         {
282                 buf += ctx->realtarget_nchars;
283                 bufsize -= ctx->realtarget_nchars;
284         }
285
286         /* Translate the WIM inode's reparse data into the link target.  */
287         sret = wim_inode_readlink(inode, buf, bufsize - 1, lte_override);
288         if (sret < 0) {
289                 errno = -sret;
290                 return WIMLIB_ERR_READLINK;
291         }
292         buf[sret] = '\0';
293
294         if ((ctx->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) &&
295             buf[0] == '/')
296         {
297                 /* Fix absolute symbolic link target to point into the
298                  * actual extraction destination.  */
299                 tmemcpy(target, ctx->realtarget, ctx->realtarget_nchars);
300                 fixed_target = target;
301         } else {
302                 /* Keep same link target.  */
303                 fixed_target = buf;
304         }
305
306         /* Call into the apply_operations to create the symbolic link.  */
307         DEBUG("Creating symlink \"%"TS"\" => \"%"TS"\"",
308               path, fixed_target);
309         ret = ctx->ops->create_symlink(fixed_target, path, ctx);
310         if (ret) {
311                 ERROR_WITH_ERRNO("Failed to create symlink "
312                                  "\"%"TS"\" => \"%"TS"\"", path, fixed_target);
313                 return ret;
314         }
315
316         /* Account for reparse data consumed.  */
317         update_extract_progress(ctx,
318                                 (lte_override ? lte_override :
319                                       inode_unnamed_lte_resolved(inode)));
320         return 0;
321 }
322 #endif /* !__WIN32__ */
323
324 /* Create a file, directory, or symbolic link.  */
325 static int
326 extract_inode(const tchar *path, struct apply_ctx *ctx, struct wim_inode *inode)
327 {
328         int ret;
329
330 #ifndef __WIN32__
331         if (ctx->supported_features.symlink_reparse_points &&
332             !ctx->supported_features.reparse_points &&
333             inode_is_symlink(inode))
334         {
335                 ret = extract_symlink(path, ctx, inode, NULL);
336         } else
337 #endif /* !__WIN32__ */
338         if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY) {
339                 ret = ctx->ops->create_directory(path, ctx, &inode->extract_cookie);
340                 if (ret) {
341                         ERROR_WITH_ERRNO("Failed to create the directory "
342                                          "\"%"TS"\"", path);
343                 }
344         } else if ((inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) &&
345                     ctx->ops->extract_encrypted_stream_creates_file &&
346                     ctx->supported_features.encrypted_files) {
347                 ret = ctx->ops->extract_encrypted_stream(
348                                 path, inode_unnamed_lte_resolved(inode), ctx);
349                 if (ret) {
350                         ERROR_WITH_ERRNO("Failed to create and extract "
351                                          "encrypted file \"%"TS"\"", path);
352                 }
353         } else {
354                 ret = ctx->ops->create_file(path, ctx, &inode->extract_cookie);
355                 if (ret) {
356                         ERROR_WITH_ERRNO("Failed to create the file "
357                                          "\"%"TS"\"", path);
358                 }
359         }
360         return ret;
361 }
362
363 static int
364 extract_hardlink(const tchar *oldpath, const tchar *newpath,
365                  struct apply_ctx *ctx)
366 {
367         int ret;
368
369         DEBUG("Creating hardlink \"%"TS"\" => \"%"TS"\"", newpath, oldpath);
370         ret = ctx->ops->create_hardlink(oldpath, newpath, ctx);
371         if (ret) {
372                 ERROR_WITH_ERRNO("Failed to create hardlink "
373                                  "\"%"TS"\" => \"%"TS"\"",
374                                  newpath, oldpath);
375         }
376         return ret;
377 }
378
379 #ifdef __WIN32__
380 static int
381 try_extract_rpfix(u8 *rpbuf,
382                   u16 *rpbuflen_p,
383                   const wchar_t *extract_root_realpath,
384                   unsigned extract_root_realpath_nchars)
385 {
386         struct reparse_data rpdata;
387         wchar_t *target;
388         size_t target_nchars;
389         size_t stripped_nchars;
390         wchar_t *stripped_target;
391         wchar_t stripped_target_nchars;
392         int ret;
393
394         utf16lechar *new_target;
395         utf16lechar *new_print_name;
396         size_t new_target_nchars;
397         size_t new_print_name_nchars;
398         utf16lechar *p;
399
400         ret = parse_reparse_data(rpbuf, *rpbuflen_p, &rpdata);
401         if (ret)
402                 return ret;
403
404         if (extract_root_realpath[0] == L'\0' ||
405             extract_root_realpath[1] != L':' ||
406             extract_root_realpath[2] != L'\\')
407                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
408
409         ret = parse_substitute_name(rpdata.substitute_name,
410                                     rpdata.substitute_name_nbytes,
411                                     rpdata.rptag);
412         if (ret < 0)
413                 return 0;
414         stripped_nchars = ret;
415         target = rpdata.substitute_name;
416         target_nchars = rpdata.substitute_name_nbytes / sizeof(utf16lechar);
417         stripped_target = target + stripped_nchars;
418         stripped_target_nchars = target_nchars - stripped_nchars;
419
420         new_target = alloca((6 + extract_root_realpath_nchars +
421                              stripped_target_nchars) * sizeof(utf16lechar));
422
423         p = new_target;
424         if (stripped_nchars == 6) {
425                 /* Include \??\ prefix if it was present before */
426                 p = wmempcpy(p, L"\\??\\", 4);
427         }
428
429         /* Print name excludes the \??\ if present. */
430         new_print_name = p;
431         if (stripped_nchars != 0) {
432                 /* Get drive letter from real path to extract root, if a drive
433                  * letter was present before. */
434                 *p++ = extract_root_realpath[0];
435                 *p++ = extract_root_realpath[1];
436         }
437         /* Copy the rest of the extract root */
438         p = wmempcpy(p, extract_root_realpath + 2, extract_root_realpath_nchars - 2);
439
440         /* Append the stripped target */
441         p = wmempcpy(p, stripped_target, stripped_target_nchars);
442         new_target_nchars = p - new_target;
443         new_print_name_nchars = p - new_print_name;
444
445         if (new_target_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE ||
446             new_print_name_nchars * sizeof(utf16lechar) >= REPARSE_POINT_MAX_SIZE)
447                 return WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED;
448
449         rpdata.substitute_name = new_target;
450         rpdata.substitute_name_nbytes = new_target_nchars * sizeof(utf16lechar);
451         rpdata.print_name = new_print_name;
452         rpdata.print_name_nbytes = new_print_name_nchars * sizeof(utf16lechar);
453         return make_reparse_buffer(&rpdata, rpbuf, rpbuflen_p);
454 }
455 #endif /* __WIN32__ */
456
457 /* Set reparse data on extracted file or directory that has
458  * FILE_ATTRIBUTE_REPARSE_POINT set.  */
459 static int
460 extract_reparse_data(const tchar *path, struct apply_ctx *ctx,
461                      struct wim_inode *inode,
462                      struct wim_lookup_table_entry *lte_override)
463 {
464         int ret;
465         u8 rpbuf[REPARSE_POINT_MAX_SIZE];
466         u16 rpbuflen;
467
468         ret = wim_inode_get_reparse_data(inode, rpbuf, &rpbuflen, lte_override);
469         if (ret)
470                 goto error;
471
472 #ifdef __WIN32__
473         /* Fix up target of absolute symbolic link or junction points so
474          * that they point into the actual extraction target.  */
475         if ((ctx->extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) &&
476             (inode->i_reparse_tag == WIM_IO_REPARSE_TAG_SYMLINK ||
477              inode->i_reparse_tag == WIM_IO_REPARSE_TAG_MOUNT_POINT) &&
478             !inode->i_not_rpfixed)
479         {
480                 ret = try_extract_rpfix(rpbuf, &rpbuflen, ctx->realtarget,
481                                         ctx->realtarget_nchars);
482                 if (ret && !(ctx->extract_flags &
483                              WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS))
484                 {
485                         WARNING("Reparse point fixup of \"%"TS"\" "
486                                 "failed", path);
487                         ret = 0;
488                 }
489                 if (ret)
490                         goto error;
491         }
492 #endif
493
494         ret = ctx->ops->set_reparse_data(path, rpbuf, rpbuflen, ctx);
495
496         /* On Windows, the SeCreateSymbolicLink privilege is required to create
497          * symbolic links.  To be more friendly towards non-Administrator users,
498          * we merely warn the user if symbolic links cannot be created due to
499          * insufficient permissions or privileges, unless
500          * WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS was provided.  */
501 #ifdef __WIN32__
502         if (ret && inode_is_symlink(inode) &&
503             (errno == EACCES || errno == EPERM) &&
504             !(ctx->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS))
505         {
506                 WARNING("Can't set reparse data on \"%"TS"\": "
507                         "Access denied!\n"
508                         "          You may be trying to "
509                         "extract a symbolic link without the\n"
510                         "          SeCreateSymbolicLink privilege, "
511                         "which by default non-Administrator\n"
512                         "          accounts do not have.",
513                         path);
514                 ret = 0;
515         }
516 #endif
517         if (ret)
518                 goto error;
519
520         /* Account for reparse data consumed.  */
521         update_extract_progress(ctx,
522                                 (lte_override ? lte_override :
523                                       inode_unnamed_lte_resolved(inode)));
524         return 0;
525
526 error:
527         ERROR_WITH_ERRNO("Failed to set reparse data on \"%"TS"\"", path);
528         return ret;
529 }
530
531 /*
532  * Extract zero or more streams to a file.
533  *
534  * This function operates slightly differently depending on whether @lte_spec is
535  * NULL or not.  When @lte_spec is NULL, the behavior is to extract the default
536  * file contents (unnamed stream), and, if named data streams are supported in
537  * the extract mode and volume, any named data streams.  When @lte_spec is NULL,
538  * the behavior is to extract only all copies of the stream @lte_spec, and in
539  * addition use @lte_spec to set the reparse data or create the symbolic link if
540  * appropriate.
541  *
542  * @path
543  *      Path to file to extract (as can be passed to apply_operations
544  *      functions).
545  * @ctx
546  *      Apply context.
547  * @dentry
548  *      WIM dentry that corresponds to the file being extracted.
549  * @lte_spec
550  *      If non-NULL, specifies the lookup table entry for a stream to extract,
551  *      and only that stream will be extracted (although there may be more than
552  *      one instance of it).
553  * @lte_override
554  *      Used only if @lte_spec != NULL; it is passed to the extraction functions
555  *      rather than @lte_spec, allowing the location of the stream to be
556  *      overridden.  (This is used when the WIM is being read from a nonseekable
557  *      file, such as a pipe, when streams need to be used more than once; each
558  *      such stream is extracted to a temporary file.)
559  */
560 static int
561 extract_streams(const tchar *path, struct apply_ctx *ctx,
562                 struct wim_dentry *dentry,
563                 struct wim_lookup_table_entry *lte_spec,
564                 struct wim_lookup_table_entry *lte_override)
565 {
566         struct wim_inode *inode = dentry->d_inode;
567         struct wim_lookup_table_entry *lte;
568         file_spec_t file_spec;
569         int ret;
570
571         if (dentry->was_hardlinked)
572                 return 0;
573
574 #ifdef ENABLE_DEBUG
575         if (lte_spec) {
576                 char sha1_str[100];
577                 char *p = sha1_str;
578                 for (unsigned i = 0; i < SHA1_HASH_SIZE; i++)
579                         p += sprintf(p, "%02x", lte_override->hash[i]);
580                 DEBUG("Extracting stream SHA1=%s to \"%"TS"\"",
581                       sha1_str, path, inode->i_ino);
582         } else {
583                 DEBUG("Extracting streams to \"%"TS"\"", path, inode->i_ino);
584         }
585 #endif
586
587         if (ctx->ops->uses_cookies)
588                 file_spec.cookie = inode->extract_cookie;
589         else
590                 file_spec.path = path;
591
592         /* Unnamed data stream.  */
593         lte = inode_unnamed_lte_resolved(inode);
594         if (lte && (!lte_spec || lte == lte_spec)) {
595                 if (lte_spec)
596                         lte = lte_override;
597                 if (!(inode->i_attributes & (FILE_ATTRIBUTE_DIRECTORY |
598                                              FILE_ATTRIBUTE_REPARSE_POINT)))
599                 {
600                         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED &&
601                             ctx->supported_features.encrypted_files) {
602                                 if (!ctx->ops->extract_encrypted_stream_creates_file) {
603                                         ret = ctx->ops->extract_encrypted_stream(
604                                                                 path, lte, ctx);
605                                         if (ret)
606                                                 goto error;
607                                 }
608                         } else {
609                                 ret = ctx->ops->extract_unnamed_stream(
610                                                         file_spec, lte, ctx);
611                                 if (ret)
612                                         goto error;
613                         }
614                         update_extract_progress(ctx, lte);
615                 }
616                 else if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT)
617                 {
618                         ret = 0;
619                         if (ctx->supported_features.reparse_points)
620                                 ret = extract_reparse_data(path, ctx, inode, lte);
621                 #ifndef __WIN32__
622                         else if ((inode_is_symlink(inode) &&
623                                   ctx->supported_features.symlink_reparse_points))
624                                 ret = extract_symlink(path, ctx, inode, lte);
625                 #endif
626                         if (ret)
627                                 return ret;
628                 }
629         }
630
631         /* Named data streams.  */
632         if (can_extract_named_data_streams(ctx)) {
633                 for (u16 i = 0; i < inode->i_num_ads; i++) {
634                         struct wim_ads_entry *entry = &inode->i_ads_entries[i];
635
636                         if (!ads_entry_is_named_stream(entry))
637                                 continue;
638                         lte = entry->lte;
639                         if (!lte)
640                                 continue;
641                         if (lte_spec && lte_spec != lte)
642                                 continue;
643                         if (lte_spec)
644                                 lte = lte_override;
645                         ret = ctx->ops->extract_named_stream(file_spec, entry->stream_name,
646                                                              entry->stream_name_nbytes / 2,
647                                                              lte, ctx);
648                         if (ret)
649                                 goto error;
650                         update_extract_progress(ctx, lte);
651                 }
652         }
653         return 0;
654
655 error:
656         ERROR_WITH_ERRNO("Failed to extract data of \"%"TS"\"", path);
657         return ret;
658 }
659
660 /* Set attributes on an extracted file or directory if supported by the
661  * extraction mode.  */
662 static int
663 extract_file_attributes(const tchar *path, struct apply_ctx *ctx,
664                         struct wim_dentry *dentry, unsigned pass)
665 {
666         int ret;
667
668         if (ctx->ops->set_file_attributes &&
669             !(dentry == ctx->extract_root && ctx->root_dentry_is_special)) {
670                 u32 attributes = dentry->d_inode->i_attributes;
671
672                 /* Clear unsupported attributes.  */
673                 attributes &= ctx->supported_attributes_mask;
674
675                 if ((attributes & FILE_ATTRIBUTE_DIRECTORY &&
676                      !ctx->supported_features.encrypted_directories) ||
677                     (!(attributes & FILE_ATTRIBUTE_DIRECTORY) &&
678                      !ctx->supported_features.encrypted_files))
679                 {
680                         attributes &= ~FILE_ATTRIBUTE_ENCRYPTED;
681                 }
682
683                 if (attributes == 0)
684                         attributes = FILE_ATTRIBUTE_NORMAL;
685
686                 ret = ctx->ops->set_file_attributes(path, attributes, ctx, pass);
687                 if (ret) {
688                         ERROR_WITH_ERRNO("Failed to set attributes on "
689                                          "\"%"TS"\"", path);
690                         return ret;
691                 }
692         }
693         return 0;
694 }
695
696
697 /* Set or remove the short (DOS) name on an extracted file or directory if
698  * supported by the extraction mode.  Since DOS names are unimportant and it's
699  * easy to run into problems setting them on Windows (SetFileShortName()
700  * requires SE_RESTORE privilege, which only the Administrator can request, and
701  * also requires DELETE access to the file), failure is ignored unless
702  * WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES is set.  */
703 static int
704 extract_short_name(const tchar *path, struct apply_ctx *ctx,
705                    struct wim_dentry *dentry)
706 {
707         int ret;
708
709         /* The root of the dentry tree being extracted may not be extracted to
710          * its original name, so its short name should be ignored.  */
711         if (dentry == ctx->extract_root)
712                 return 0;
713
714         if (ctx->supported_features.short_names) {
715                 ret = ctx->ops->set_short_name(path,
716                                                dentry->short_name,
717                                                dentry->short_name_nbytes / 2,
718                                                ctx);
719                 if (ret && (ctx->extract_flags &
720                             WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES))
721                 {
722                         ERROR_WITH_ERRNO("Failed to set short name of "
723                                          "\"%"TS"\"", path);
724                         return ret;
725                 }
726         }
727         return 0;
728 }
729
730 /* Set security descriptor, UNIX data, or neither on an extracted file, taking
731  * into account the current extraction mode and flags.  */
732 static int
733 extract_security(const tchar *path, struct apply_ctx *ctx,
734                  struct wim_dentry *dentry)
735 {
736         int ret;
737         struct wim_inode *inode = dentry->d_inode;
738
739         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_NO_ACLS)
740                 return 0;
741
742         if ((ctx->extract_root == dentry) && ctx->root_dentry_is_special)
743                 return 0;
744
745 #ifndef __WIN32__
746         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) {
747                 struct wimlib_unix_data data;
748
749                 ret = inode_get_unix_data(inode, &data, NULL);
750                 if (ret < 0)
751                         ret = 0;
752                 else if (ret == 0)
753                         ret = ctx->ops->set_unix_data(path, &data, ctx);
754                 if (ret) {
755                         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
756                                 ERROR_WITH_ERRNO("Failed to set UNIX owner, "
757                                                  "group, and/or mode on "
758                                                  "\"%"TS"\"", path);
759                                 return ret;
760                         } else {
761                                 WARNING_WITH_ERRNO("Failed to set UNIX owner, "
762                                                    "group, and/or/mode on "
763                                                    "\"%"TS"\"", path);
764                         }
765                 }
766         }
767         else
768 #endif /* __WIN32__ */
769         if (ctx->supported_features.security_descriptors &&
770             inode->i_security_id != -1)
771         {
772                 const struct wim_security_data *sd;
773                 const u8 *desc;
774                 size_t desc_size;
775
776                 sd = wim_const_security_data(ctx->wim);
777                 desc = sd->descriptors[inode->i_security_id];
778                 desc_size = sd->sizes[inode->i_security_id];
779
780                 ret = ctx->ops->set_security_descriptor(path, desc,
781                                                         desc_size, ctx);
782                 if (ret) {
783                         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_ACLS) {
784                                 ERROR_WITH_ERRNO("Failed to set security "
785                                                  "descriptor on \"%"TS"\"", path);
786                                 return ret;
787                         } else {
788                         #if 0
789                                 if (errno != EACCES) {
790                                         WARNING_WITH_ERRNO("Failed to set "
791                                                            "security descriptor "
792                                                            "on \"%"TS"\"", path);
793                                 }
794                         #endif
795                                 ctx->no_security_descriptors++;
796                         }
797                 }
798         }
799         return 0;
800 }
801
802 /* Set timestamps on an extracted file.  Failure is warning-only unless
803  * WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS is set.  */
804 static int
805 extract_timestamps(const tchar *path, struct apply_ctx *ctx,
806                    struct wim_dentry *dentry)
807 {
808         struct wim_inode *inode = dentry->d_inode;
809         int ret;
810
811         if ((ctx->extract_root == dentry) && ctx->root_dentry_is_special)
812                 return 0;
813
814         if (ctx->ops->set_timestamps) {
815                 ret = ctx->ops->set_timestamps(path,
816                                                inode->i_creation_time,
817                                                inode->i_last_write_time,
818                                                inode->i_last_access_time,
819                                                ctx);
820                 if (ret) {
821                         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS) {
822                                 ERROR_WITH_ERRNO("Failed to set timestamps "
823                                                  "on \"%"TS"\"", path);
824                                 return ret;
825                         } else {
826                                 WARNING_WITH_ERRNO("Failed to set timestamps "
827                                                    "on \"%"TS"\"", path);
828                         }
829                 }
830         }
831         return 0;
832 }
833
834 /* Check whether the extraction of a dentry should be skipped completely.  */
835 static bool
836 dentry_is_supported(struct wim_dentry *dentry,
837                     const struct wim_features *supported_features)
838 {
839         struct wim_inode *inode = dentry->d_inode;
840
841         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
842                 return supported_features->reparse_points ||
843                         (inode_is_symlink(inode) &&
844                          supported_features->symlink_reparse_points);
845         }
846         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) {
847                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY)
848                         return supported_features->encrypted_directories != 0;
849                 else
850                         return supported_features->encrypted_files != 0;
851         }
852         return true;
853 }
854
855 /* Given a WIM dentry to extract, build the path to which to extract it, in the
856  * format understood by the callbacks in the apply_operations being used.
857  *
858  * Write the resulting path into @path, which must have room for at least
859  * ctx->ops->max_path characters including the null-terminator.
860  *
861  * Return %true if successful; %false if this WIM dentry doesn't actually need
862  * to be extracted or if the calculated path exceeds ctx->ops->max_path
863  * characters.
864  *
865  * This function clobbers the tmp_list member of @dentry and its ancestors up
866  * until the extraction root.  */
867 static bool
868 build_extraction_path(tchar path[], struct wim_dentry *dentry,
869                       struct apply_ctx *ctx)
870 {
871         size_t path_nchars;
872         LIST_HEAD(ancestor_list);
873         tchar *p = path;
874         const tchar *target_prefix;
875         size_t target_prefix_nchars;
876         struct wim_dentry *d;
877
878         if (dentry->extraction_skipped)
879                 return false;
880
881         path_nchars = ctx->ops->path_prefix_nchars;
882
883         if (ctx->ops->requires_realtarget_in_paths) {
884                 target_prefix        = ctx->realtarget;
885                 target_prefix_nchars = ctx->realtarget_nchars;
886         } else if (ctx->ops->requires_target_in_paths) {
887                 target_prefix        = ctx->target;
888                 target_prefix_nchars = ctx->target_nchars;
889         } else {
890                 target_prefix        = NULL;
891                 target_prefix_nchars = 0;
892         }
893         path_nchars += target_prefix_nchars;
894
895         for (d = dentry; d != ctx->extract_root; d = d->parent) {
896                 path_nchars += d->extraction_name_nchars + 1;
897                 list_add(&d->tmp_list, &ancestor_list);
898         }
899
900         path_nchars++; /* null terminator */
901
902         if (path_nchars > ctx->ops->path_max) {
903                 WARNING("\"%"TS"\": Path too long to extract",
904                         dentry_full_path(dentry));
905                 return false;
906         }
907
908         p = tmempcpy(p, ctx->ops->path_prefix, ctx->ops->path_prefix_nchars);
909         p = tmempcpy(p, target_prefix, target_prefix_nchars);
910         list_for_each_entry(d, &ancestor_list, tmp_list) {
911                 *p++ = ctx->ops->path_separator;
912                 p = tmempcpy(p, d->extraction_name, d->extraction_name_nchars);
913         }
914         *p++ = T('\0');
915         wimlib_assert(p - path == path_nchars);
916         return true;
917 }
918
919 static unsigned
920 get_num_path_components(const tchar *path, tchar path_separator)
921 {
922         unsigned num_components = 0;
923 #ifdef __WIN32__
924         /* Ignore drive letter.  */
925         if (path[0] != L'\0' && path[1] == L':')
926                 path += 2;
927 #endif
928
929         while (*path) {
930                 while (*path == path_separator)
931                         path++;
932                 if (*path)
933                         num_components++;
934                 while (*path && *path != path_separator)
935                         path++;
936         }
937         return num_components;
938 }
939
940 static int
941 extract_multiimage_symlink(const tchar *oldpath, const tchar *newpath,
942                            struct apply_ctx *ctx, struct wim_dentry *dentry)
943 {
944         size_t num_raw_path_components;
945         const struct wim_dentry *d;
946         size_t num_target_path_components;
947         tchar *p;
948         const tchar *p_old;
949         int ret;
950
951         num_raw_path_components = 0;
952         for (d = dentry; d != ctx->extract_root; d = d->parent)
953                 num_raw_path_components++;
954
955         if (ctx->ops->requires_realtarget_in_paths)
956                 num_target_path_components = get_num_path_components(ctx->realtarget,
957                                                                      ctx->ops->path_separator);
958         else if (ctx->ops->requires_target_in_paths)
959                 num_target_path_components = get_num_path_components(ctx->target,
960                                                                      ctx->ops->path_separator);
961         else
962                 num_target_path_components = 0;
963
964         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_MULTI_IMAGE) {
965                 wimlib_assert(num_target_path_components > 0);
966                 num_raw_path_components++;
967                 num_target_path_components--;
968         }
969
970         p_old = oldpath + ctx->ops->path_prefix_nchars;
971 #ifdef __WIN32__
972         if (p_old[0] != L'\0' && p_old[1] == ':')
973                 p_old += 2;
974 #endif
975         while (*p_old == ctx->ops->path_separator)
976                 p_old++;
977         while (--num_target_path_components) {
978                 while (*p_old != ctx->ops->path_separator)
979                         p_old++;
980                 while (*p_old == ctx->ops->path_separator)
981                         p_old++;
982         }
983
984         tchar symlink_target[tstrlen(p_old) + 3 * num_raw_path_components + 1];
985
986         p = &symlink_target[0];
987         while (num_raw_path_components--) {
988                 *p++ = '.';
989                 *p++ = '.';
990                 *p++ = ctx->ops->path_separator;
991         }
992         tstrcpy(p, p_old);
993         DEBUG("Creating symlink \"%"TS"\" => \"%"TS"\"",
994               newpath, symlink_target);
995         ret = ctx->ops->create_symlink(symlink_target, newpath, ctx);
996         if (ret) {
997                 ERROR_WITH_ERRNO("Failed to create symlink "
998                                  "\"%"TS"\" => \"%"TS"\"",
999                                  newpath, symlink_target);
1000         }
1001         return ret;
1002 }
1003
1004 /* Create the "skeleton" of an extracted file or directory.  Don't yet extract
1005  * data streams, reparse data (including symbolic links), timestamps, and
1006  * security descriptors.  Basically, everything that doesn't require reading
1007  * non-metadata resources from the WIM file and isn't delayed until the final
1008  * pass.  */
1009 static int
1010 do_dentry_extract_skeleton(tchar path[], struct wim_dentry *dentry,
1011                            struct apply_ctx *ctx)
1012 {
1013         struct wim_inode *inode = dentry->d_inode;
1014         int ret;
1015         const tchar *oldpath;
1016
1017         if (unlikely(is_linked_extraction(ctx))) {
1018                 struct wim_lookup_table_entry *unnamed_lte;
1019
1020                 unnamed_lte = inode_unnamed_lte_resolved(dentry->d_inode);
1021                 if (unnamed_lte && unnamed_lte->extracted_file) {
1022                         oldpath = unnamed_lte->extracted_file;
1023                         if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_HARDLINK)
1024                                 goto hardlink;
1025                         else
1026                                 goto symlink;
1027                 }
1028         }
1029
1030         /* Create hard link if this dentry corresponds to an already-extracted
1031          * inode.  */
1032         if (inode->i_extracted_file) {
1033                 oldpath = inode->i_extracted_file;
1034                 goto hardlink;
1035         }
1036
1037         /* Skip symlinks unless they can be extracted as reparse points rather
1038          * than created directly.  */
1039         if (inode_is_symlink(inode) && !ctx->supported_features.reparse_points)
1040                 return 0;
1041
1042         /* Create this file or directory unless it's the extraction root, which
1043          * was already created if necessary.  */
1044         if (dentry != ctx->extract_root) {
1045                 ret = extract_inode(path, ctx, inode);
1046                 if (ret)
1047                         return ret;
1048         }
1049
1050         /* Create empty named data streams.  */
1051         if (can_extract_named_data_streams(ctx)) {
1052                 for (u16 i = 0; i < inode->i_num_ads; i++) {
1053                         file_spec_t file_spec;
1054                         struct wim_ads_entry *entry = &inode->i_ads_entries[i];
1055
1056                         if (!ads_entry_is_named_stream(entry))
1057                                 continue;
1058                         if (entry->lte)
1059                                 continue;
1060                         if (ctx->ops->uses_cookies)
1061                                 file_spec.cookie = inode->extract_cookie;
1062                         else
1063                                 file_spec.path = path;
1064                         ret = ctx->ops->extract_named_stream(file_spec,
1065                                                              entry->stream_name,
1066                                                              entry->stream_name_nbytes / 2,
1067                                                              entry->lte, ctx);
1068                         if (ret) {
1069                                 ERROR_WITH_ERRNO("\"%"TS"\": failed to create "
1070                                                  "empty named data stream",
1071                                                  path);
1072                                 return ret;
1073                         }
1074                 }
1075         }
1076
1077         /* Set file attributes (if supported).  */
1078         ret = extract_file_attributes(path, ctx, dentry, 0);
1079         if (ret)
1080                 return ret;
1081
1082         /* Set or remove file short name (if supported).  */
1083         ret = extract_short_name(path, ctx, dentry);
1084         if (ret)
1085                 return ret;
1086
1087         /* If inode has multiple links and hard links are supported in this
1088          * extraction mode and volume, save the path to the extracted file in
1089          * case it's needed to create a hard link.  */
1090         if (unlikely(is_linked_extraction(ctx))) {
1091                 struct wim_lookup_table_entry *unnamed_lte;
1092
1093                 unnamed_lte = inode_unnamed_lte_resolved(dentry->d_inode);
1094                 if (unnamed_lte) {
1095                         unnamed_lte->extracted_file = TSTRDUP(path);
1096                         if (!unnamed_lte->extracted_file)
1097                                 return WIMLIB_ERR_NOMEM;
1098                 }
1099         } else if (inode->i_nlink > 1 && ctx->supported_features.hard_links) {
1100                 inode->i_extracted_file = TSTRDUP(path);
1101                 if (!inode->i_extracted_file)
1102                         return WIMLIB_ERR_NOMEM;
1103         }
1104         return 0;
1105
1106 symlink:
1107         ret = extract_multiimage_symlink(oldpath, path, ctx, dentry);
1108         if (ret)
1109                 return ret;
1110         dentry->was_hardlinked = 1;
1111         return 0;
1112
1113 hardlink:
1114         ret = extract_hardlink(oldpath, path, ctx);
1115         if (ret)
1116                 return ret;
1117         dentry->was_hardlinked = 1;
1118         return 0;
1119 }
1120
1121 /* This is a wrapper around do_dentry_extract_skeleton() that handles building
1122  * the path, doing short name reordering.  This is also idempotent; dentries
1123  * already processed have skeleton_extracted set and no action is taken.  See
1124  * apply_operations.requires_short_name_reordering for more details about short
1125  * name reordering.  */
1126 static int
1127 dentry_extract_skeleton(struct wim_dentry *dentry, void *_ctx)
1128 {
1129         struct apply_ctx *ctx = _ctx;
1130         tchar path[ctx->ops->path_max];
1131         struct wim_dentry *orig_dentry;
1132         struct wim_dentry *other_dentry;
1133         int ret;
1134
1135         if (dentry->skeleton_extracted)
1136                 return 0;
1137
1138         orig_dentry = NULL;
1139         if (ctx->supported_features.short_names
1140             && ctx->ops->requires_short_name_reordering
1141             && !dentry_has_short_name(dentry)
1142             && !dentry->d_inode->i_dos_name_extracted)
1143         {
1144                 inode_for_each_dentry(other_dentry, dentry->d_inode) {
1145                         if (dentry_has_short_name(other_dentry)
1146                             && !other_dentry->skeleton_extracted
1147                             && other_dentry->in_extraction_tree)
1148                         {
1149                                 DEBUG("Creating %"TS" before %"TS" "
1150                                       "to guarantee correct DOS name extraction",
1151                                       dentry_full_path(other_dentry),
1152                                       dentry_full_path(dentry));
1153                                 orig_dentry = dentry;
1154                                 dentry = other_dentry;
1155                                 break;
1156                         }
1157                 }
1158         }
1159 again:
1160         if (!build_extraction_path(path, dentry, ctx))
1161                 return 0;
1162         ret = do_dentry_extract_skeleton(path, dentry, ctx);
1163         if (ret)
1164                 return ret;
1165
1166         dentry->skeleton_extracted = 1;
1167
1168         if (orig_dentry) {
1169                 dentry = orig_dentry;
1170                 orig_dentry = NULL;
1171                 goto again;
1172         }
1173         dentry->d_inode->i_dos_name_extracted = 1;
1174         return 0;
1175 }
1176
1177 static int
1178 dentry_extract_dir_skeleton(struct wim_dentry *dentry, void *_ctx)
1179 {
1180         if (dentry->d_inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY)
1181                 return dentry_extract_skeleton(dentry, _ctx);
1182         return 0;
1183 }
1184
1185 /* Create a file or directory, then immediately extract all streams.  This
1186  * assumes that WIMLIB_EXTRACT_FLAG_SEQUENTIAL is not specified, since the WIM
1187  * may not be read sequentially by this function.  */
1188 static int
1189 dentry_extract(struct wim_dentry *dentry, void *_ctx)
1190 {
1191         struct apply_ctx *ctx = _ctx;
1192         tchar path[ctx->ops->path_max];
1193         int ret;
1194
1195         ret = dentry_extract_skeleton(dentry, ctx);
1196         if (ret)
1197                 return ret;
1198
1199         if (!build_extraction_path(path, dentry, ctx))
1200                 return 0;
1201
1202         return extract_streams(path, ctx, dentry, NULL, NULL);
1203 }
1204
1205 /* Extract all instances of the stream @lte that are being extracted in this
1206  * call of extract_tree().  @can_seek specifies whether the WIM file descriptor
1207  * is seekable or not (e.g. is a pipe).  If not and the stream needs to be
1208  * extracted multiple times, it is extracted to a temporary file first.
1209  *
1210  * This is intended for use with sequential extraction of a WIM image
1211  * (WIMLIB_EXTRACT_FLAG_SEQUENTIAL specified).  */
1212 static int
1213 extract_stream_instances(struct wim_lookup_table_entry *lte,
1214                          struct apply_ctx *ctx, bool can_seek)
1215 {
1216         struct wim_dentry **lte_dentries;
1217         struct wim_lookup_table_entry *lte_tmp = NULL;
1218         struct wim_lookup_table_entry *lte_override;
1219         tchar *stream_tmp_filename = NULL;
1220         tchar path[ctx->ops->path_max];
1221         unsigned i;
1222         int ret;
1223
1224         if (lte->out_refcnt <= ARRAY_LEN(lte->inline_lte_dentries))
1225                 lte_dentries = lte->inline_lte_dentries;
1226         else
1227                 lte_dentries = lte->lte_dentries;
1228
1229         if (likely(can_seek || lte->out_refcnt < 2)) {
1230                 lte_override = lte;
1231         } else {
1232                 /* Need to extract stream to temporary file.  */
1233                 struct filedes fd;
1234                 int raw_fd;
1235
1236                 stream_tmp_filename = ttempnam(NULL, T("wimlib"));
1237                 if (!stream_tmp_filename) {
1238                         ERROR_WITH_ERRNO("Failed to create temporary filename");
1239                         ret = WIMLIB_ERR_OPEN;
1240                         goto out;
1241                 }
1242
1243                 lte_tmp = memdup(lte, sizeof(struct wim_lookup_table_entry));
1244                 if (!lte_tmp) {
1245                         ret = WIMLIB_ERR_NOMEM;
1246                         goto out_free_stream_tmp_filename;
1247                 }
1248                 lte_tmp->resource_location = RESOURCE_IN_FILE_ON_DISK;
1249                 lte_tmp->file_on_disk = stream_tmp_filename;
1250                 lte_override = lte_tmp;
1251
1252                 raw_fd = topen(stream_tmp_filename,
1253                                O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, 0600);
1254                 if (raw_fd < 0) {
1255                         ERROR_WITH_ERRNO("Failed to open temporary file");
1256                         ret = WIMLIB_ERR_OPEN;
1257                         goto out_free_lte_tmp;
1258                 }
1259                 filedes_init(&fd, raw_fd);
1260                 ret = extract_wim_resource_to_fd(lte, &fd,
1261                                                  wim_resource_size(lte));
1262                 if (filedes_close(&fd) && !ret)
1263                         ret = WIMLIB_ERR_WRITE;
1264                 if (ret)
1265                         goto out_unlink_stream_tmp_file;
1266         }
1267
1268         /* Extract all instances of the stream, reading either from the stream
1269          * in the WIM file or from the temporary file containing the stream.
1270          * dentry->tmp_flag is used to ensure that each dentry is processed only
1271          * once regardless of how many times this stream appears in the streams
1272          * of the corresponding inode.  */
1273         for (i = 0; i < lte->out_refcnt; i++) {
1274                 struct wim_dentry *dentry = lte_dentries[i];
1275
1276                 if (dentry->tmp_flag)
1277                         continue;
1278                 if (!build_extraction_path(path, dentry, ctx))
1279                         continue;
1280                 ret = extract_streams(path, ctx, dentry,
1281                                       lte, lte_override);
1282                 if (ret)
1283                         goto out_clear_tmp_flags;
1284                 dentry->tmp_flag = 1;
1285         }
1286         ret = 0;
1287 out_clear_tmp_flags:
1288         for (i = 0; i < lte->out_refcnt; i++)
1289                 lte_dentries[i]->tmp_flag = 0;
1290 out_unlink_stream_tmp_file:
1291         if (stream_tmp_filename)
1292                 tunlink(stream_tmp_filename);
1293 out_free_lte_tmp:
1294         FREE(lte_tmp);
1295 out_free_stream_tmp_filename:
1296         FREE(stream_tmp_filename);
1297 out:
1298         return ret;
1299 }
1300
1301 /* Extracts a list of streams (ctx.stream_list), assuming that the directory
1302  * structure and empty files were already created.  This relies on the
1303  * per-`struct wim_lookup_table_entry' list of dentries that reference each
1304  * stream that was constructed earlier.  Streams are extracted exactly in the
1305  * order of the stream list; however, unless the WIM's file descriptor is
1306  * detected to be non-seekable, streams may be read from the WIM file more than
1307  * one time if multiple copies need to be extracted.  */
1308 static int
1309 extract_stream_list(struct apply_ctx *ctx)
1310 {
1311         struct wim_lookup_table_entry *lte;
1312         bool can_seek;
1313         int ret;
1314
1315         can_seek = (lseek(ctx->wim->in_fd.fd, 0, SEEK_CUR) != -1);
1316         list_for_each_entry(lte, &ctx->stream_list, extraction_list) {
1317                 ret = extract_stream_instances(lte, ctx, can_seek);
1318                 if (ret)
1319                         return ret;
1320         }
1321         return 0;
1322 }
1323
1324 #define PWM_ALLOW_WIM_HDR 0x00001
1325 #define PWM_SILENT_EOF    0x00002
1326
1327 /* Read the header from a stream in a pipable WIM.  */
1328 static int
1329 read_pwm_stream_header(WIMStruct *pwm, struct wim_lookup_table_entry *lte,
1330                        int flags, struct wim_header_disk *hdr_ret)
1331 {
1332         union {
1333                 struct pwm_stream_hdr stream_hdr;
1334                 struct wim_header_disk pwm_hdr;
1335         } buf;
1336         int ret;
1337
1338         ret = full_read(&pwm->in_fd, &buf.stream_hdr, sizeof(buf.stream_hdr));
1339         if (ret)
1340                 goto read_error;
1341
1342         if ((flags & PWM_ALLOW_WIM_HDR) && buf.stream_hdr.magic == PWM_MAGIC) {
1343                 BUILD_BUG_ON(sizeof(buf.pwm_hdr) < sizeof(buf.stream_hdr));
1344                 ret = full_read(&pwm->in_fd, &buf.stream_hdr + 1,
1345                                 sizeof(buf.pwm_hdr) - sizeof(buf.stream_hdr));
1346
1347                 if (ret)
1348                         goto read_error;
1349                 lte->resource_location = RESOURCE_NONEXISTENT;
1350                 memcpy(hdr_ret, &buf.pwm_hdr, sizeof(buf.pwm_hdr));
1351                 return 0;
1352         }
1353
1354         if (buf.stream_hdr.magic != PWM_STREAM_MAGIC) {
1355                 ERROR("Data read on pipe is invalid (expected stream header).");
1356                 return WIMLIB_ERR_INVALID_PIPABLE_WIM;
1357         }
1358
1359         lte->resource_entry.original_size = le64_to_cpu(buf.stream_hdr.uncompressed_size);
1360         copy_hash(lte->hash, buf.stream_hdr.hash);
1361         lte->resource_entry.flags = le32_to_cpu(buf.stream_hdr.flags);
1362         lte->resource_entry.offset = pwm->in_fd.offset;
1363         lte->resource_location = RESOURCE_IN_WIM;
1364         lte->wim = pwm;
1365         if (lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED) {
1366                 lte->compression_type = pwm->compression_type;
1367                 lte->resource_entry.size = 0;
1368         } else {
1369                 lte->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
1370                 lte->resource_entry.size = lte->resource_entry.original_size;
1371         }
1372         lte->is_pipable = 1;
1373         return 0;
1374
1375 read_error:
1376         if (ret != WIMLIB_ERR_UNEXPECTED_END_OF_FILE || !(flags & PWM_SILENT_EOF))
1377                 ERROR_WITH_ERRNO("Error reading pipable WIM from pipe");
1378         return ret;
1379 }
1380
1381 static int
1382 skip_pwm_chunk_cb(const void *chunk, size_t chunk_size, void *_ctx)
1383 {
1384         return 0;
1385 }
1386
1387 /* Skip over an unneeded stream in a pipable WIM being read from a pipe.  */
1388 static int
1389 skip_pwm_stream(struct wim_lookup_table_entry *lte)
1390 {
1391         return read_partial_wim_resource(lte,
1392                                          wim_resource_size(lte),
1393                                          skip_pwm_chunk_cb,
1394                                          wim_resource_chunk_size(lte),
1395                                          NULL,
1396                                          WIMLIB_READ_RESOURCE_FLAG_RAW_CHUNKS,
1397                                          0);
1398 }
1399
1400 static int
1401 extract_streams_from_pipe(struct apply_ctx *ctx)
1402 {
1403         struct wim_lookup_table_entry *found_lte;
1404         struct wim_lookup_table_entry *needed_lte;
1405         struct wim_lookup_table *lookup_table;
1406         struct wim_header_disk pwm_hdr;
1407         int ret;
1408         int pwm_flags;
1409
1410         ret = WIMLIB_ERR_NOMEM;
1411         found_lte = new_lookup_table_entry();
1412         if (!found_lte)
1413                 goto out;
1414
1415         lookup_table = ctx->wim->lookup_table;
1416         pwm_flags = PWM_ALLOW_WIM_HDR;
1417         if ((ctx->extract_flags & WIMLIB_EXTRACT_FLAG_RESUME))
1418                 pwm_flags |= PWM_SILENT_EOF;
1419         memcpy(ctx->progress.extract.guid, ctx->wim->hdr.guid, WIM_GID_LEN);
1420         ctx->progress.extract.part_number = ctx->wim->hdr.part_number;
1421         ctx->progress.extract.total_parts = ctx->wim->hdr.total_parts;
1422         if (ctx->progress_func)
1423                 ctx->progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_SPWM_PART_BEGIN,
1424                                    &ctx->progress);
1425         while (ctx->num_streams_remaining) {
1426                 ret = read_pwm_stream_header(ctx->wim, found_lte, pwm_flags,
1427                                              &pwm_hdr);
1428                 if (ret) {
1429                         if (ret == WIMLIB_ERR_UNEXPECTED_END_OF_FILE &&
1430                             (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_RESUME))
1431                         {
1432                                 goto resume_done;
1433                         }
1434                         goto out_free_found_lte;
1435                 }
1436
1437                 if ((found_lte->resource_location != RESOURCE_NONEXISTENT)
1438                     && !(found_lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA)
1439                     && (needed_lte = lookup_resource(lookup_table, found_lte->hash))
1440                     && (needed_lte->out_refcnt))
1441                 {
1442                         copy_resource_entry(&needed_lte->resource_entry,
1443                                             &found_lte->resource_entry);
1444                         needed_lte->resource_location = found_lte->resource_location;
1445                         needed_lte->wim               = found_lte->wim;
1446                         needed_lte->compression_type  = found_lte->compression_type;
1447                         needed_lte->is_pipable        = found_lte->is_pipable;
1448
1449                         ret = extract_stream_instances(needed_lte, ctx, false);
1450                         if (ret)
1451                                 goto out_free_found_lte;
1452                         ctx->num_streams_remaining--;
1453                 } else if (found_lte->resource_location != RESOURCE_NONEXISTENT) {
1454                         ret = skip_pwm_stream(found_lte);
1455                         if (ret)
1456                                 goto out_free_found_lte;
1457                 } else {
1458                         u16 part_number = le16_to_cpu(pwm_hdr.part_number);
1459                         u16 total_parts = le16_to_cpu(pwm_hdr.total_parts);
1460
1461                         if (part_number != ctx->progress.extract.part_number ||
1462                             total_parts != ctx->progress.extract.total_parts ||
1463                             memcmp(pwm_hdr.guid, ctx->progress.extract.guid,
1464                                    WIM_GID_LEN))
1465                         {
1466                                 ctx->progress.extract.part_number = part_number;
1467                                 ctx->progress.extract.total_parts = total_parts;
1468                                 memcpy(ctx->progress.extract.guid,
1469                                        pwm_hdr.guid, WIM_GID_LEN);
1470                                 if (ctx->progress_func) {
1471                                         ctx->progress_func(
1472                                                 WIMLIB_PROGRESS_MSG_EXTRACT_SPWM_PART_BEGIN,
1473                                                            &ctx->progress);
1474                                 }
1475
1476                         }
1477                 }
1478         }
1479         ret = 0;
1480 out_free_found_lte:
1481         free_lookup_table_entry(found_lte);
1482 out:
1483         return ret;
1484
1485 resume_done:
1486         /* TODO */
1487         return 0;
1488 }
1489
1490 /* Finish extracting a file, directory, or symbolic link by setting file
1491  * security and timestamps.  */
1492 static int
1493 dentry_extract_final(struct wim_dentry *dentry, void *_ctx)
1494 {
1495         struct apply_ctx *ctx = _ctx;
1496         int ret;
1497         tchar path[ctx->ops->path_max];
1498
1499         if (!build_extraction_path(path, dentry, ctx))
1500                 return 0;
1501
1502         ret = extract_security(path, ctx, dentry);
1503         if (ret)
1504                 return ret;
1505
1506         if (ctx->ops->requires_final_set_attributes_pass) {
1507                 /* Set file attributes (if supported).  */
1508                 ret = extract_file_attributes(path, ctx, dentry, 1);
1509                 if (ret)
1510                         return ret;
1511         }
1512
1513         return extract_timestamps(path, ctx, dentry);
1514 }
1515
1516 /*
1517  * Extract a WIM dentry to standard output.
1518  *
1519  * This obviously doesn't make sense in all cases.  We return an error if the
1520  * dentry does not correspond to a regular file.  Otherwise we extract the
1521  * unnamed data stream only.
1522  */
1523 static int
1524 extract_dentry_to_stdout(struct wim_dentry *dentry)
1525 {
1526         int ret = 0;
1527         if (dentry->d_inode->i_attributes & (FILE_ATTRIBUTE_REPARSE_POINT |
1528                                              FILE_ATTRIBUTE_DIRECTORY))
1529         {
1530                 ERROR("\"%"TS"\" is not a regular file and therefore cannot be "
1531                       "extracted to standard output", dentry_full_path(dentry));
1532                 ret = WIMLIB_ERR_NOT_A_REGULAR_FILE;
1533         } else {
1534                 struct wim_lookup_table_entry *lte;
1535
1536                 lte = inode_unnamed_lte_resolved(dentry->d_inode);
1537                 if (lte) {
1538                         struct filedes _stdout;
1539                         filedes_init(&_stdout, STDOUT_FILENO);
1540                         ret = extract_wim_resource_to_fd(lte, &_stdout,
1541                                                          wim_resource_size(lte));
1542                 }
1543         }
1544         return ret;
1545 }
1546
1547 #ifdef __WIN32__
1548 static const utf16lechar replacement_char = cpu_to_le16(0xfffd);
1549 #else
1550 static const utf16lechar replacement_char = cpu_to_le16('?');
1551 #endif
1552
1553 static bool
1554 file_name_valid(utf16lechar *name, size_t num_chars, bool fix)
1555 {
1556         size_t i;
1557
1558         if (num_chars == 0)
1559                 return true;
1560         for (i = 0; i < num_chars; i++) {
1561                 switch (name[i]) {
1562         #ifdef __WIN32__
1563                 case cpu_to_le16('\\'):
1564                 case cpu_to_le16(':'):
1565                 case cpu_to_le16('*'):
1566                 case cpu_to_le16('?'):
1567                 case cpu_to_le16('"'):
1568                 case cpu_to_le16('<'):
1569                 case cpu_to_le16('>'):
1570                 case cpu_to_le16('|'):
1571         #endif
1572                 case cpu_to_le16('/'):
1573                 case cpu_to_le16('\0'):
1574                         if (fix)
1575                                 name[i] = replacement_char;
1576                         else
1577                                 return false;
1578                 }
1579         }
1580
1581 #ifdef __WIN32__
1582         if (name[num_chars - 1] == cpu_to_le16(' ') ||
1583             name[num_chars - 1] == cpu_to_le16('.'))
1584         {
1585                 if (fix)
1586                         name[num_chars - 1] = replacement_char;
1587                 else
1588                         return false;
1589         }
1590 #endif
1591         return true;
1592 }
1593
1594 static bool
1595 dentry_is_dot_or_dotdot(const struct wim_dentry *dentry)
1596 {
1597         const utf16lechar *file_name = dentry->file_name;
1598         return file_name != NULL &&
1599                 file_name[0] == cpu_to_le16('.') &&
1600                 (file_name[1] == cpu_to_le16('\0') ||
1601                  (file_name[1] == cpu_to_le16('.') &&
1602                   file_name[2] == cpu_to_le16('\0')));
1603 }
1604
1605 static int
1606 dentry_mark_skipped(struct wim_dentry *dentry, void *_ignore)
1607 {
1608         dentry->extraction_skipped = 1;
1609         return 0;
1610 }
1611
1612 /*
1613  * dentry_calculate_extraction_path-
1614  *
1615  * Calculate the actual filename component at which a WIM dentry will be
1616  * extracted, handling invalid filenames "properly".
1617  *
1618  * dentry->extraction_name usually will be set the same as dentry->file_name (on
1619  * UNIX, converted into the platform's multibyte encoding).  However, if the
1620  * file name contains characters that are not valid on the current platform or
1621  * has some other format that is not valid, leave dentry->extraction_name as
1622  * NULL and set dentry->extraction_skipped to indicate that this dentry should
1623  * not be extracted, unless the appropriate flag
1624  * WIMLIB_EXTRACT_FLAG_REPLACE_INVALID_FILENAMES is set in the extract flags, in
1625  * which case a substitute filename will be created and set instead.
1626  *
1627  * Conflicts with case-insensitive names on Windows are handled similarly; see
1628  * below.
1629  */
1630 static int
1631 dentry_calculate_extraction_path(struct wim_dentry *dentry, void *_args)
1632 {
1633         struct apply_ctx *ctx = _args;
1634         int ret;
1635
1636         dentry->in_extraction_tree = 1;
1637
1638         if (dentry == ctx->extract_root || dentry->extraction_skipped)
1639                 return 0;
1640
1641         if (!dentry_is_supported(dentry, &ctx->supported_features))
1642                 goto skip_dentry;
1643
1644         if (dentry_is_dot_or_dotdot(dentry)) {
1645                 /* WIM files shouldn't contain . or .. entries.  But if they are
1646                  * there, don't attempt to extract them. */
1647                 WARNING("Skipping extraction of unexpected . or .. file "
1648                         "\"%"TS"\"", dentry_full_path(dentry));
1649                 goto skip_dentry;
1650         }
1651
1652 #ifdef __WIN32__
1653         if (!ctx->ops->supports_case_sensitive_filenames)
1654         {
1655                 struct wim_dentry *other;
1656                 list_for_each_entry(other, &dentry->case_insensitive_conflict_list,
1657                                     case_insensitive_conflict_list)
1658                 {
1659                         if (ctx->extract_flags &
1660                             WIMLIB_EXTRACT_FLAG_ALL_CASE_CONFLICTS) {
1661                                 WARNING("\"%"TS"\" has the same "
1662                                         "case-insensitive name as "
1663                                         "\"%"TS"\"; extracting "
1664                                         "dummy name instead",
1665                                         dentry_full_path(dentry),
1666                                         dentry_full_path(other));
1667                                 goto out_replace;
1668                         } else {
1669                                 WARNING("Not extracting \"%"TS"\": "
1670                                         "has same case-insensitive "
1671                                         "name as \"%"TS"\"",
1672                                         dentry_full_path(dentry),
1673                                         dentry_full_path(other));
1674                                 goto skip_dentry;
1675                         }
1676                 }
1677         }
1678 #else   /* __WIN32__ */
1679         wimlib_assert(ctx->ops->supports_case_sensitive_filenames);
1680 #endif  /* !__WIN32__ */
1681
1682         if (file_name_valid(dentry->file_name, dentry->file_name_nbytes / 2, false)) {
1683 #ifdef __WIN32__
1684                 dentry->extraction_name = dentry->file_name;
1685                 dentry->extraction_name_nchars = dentry->file_name_nbytes / 2;
1686                 return 0;
1687 #else
1688                 return utf16le_to_tstr(dentry->file_name,
1689                                        dentry->file_name_nbytes,
1690                                        &dentry->extraction_name,
1691                                        &dentry->extraction_name_nchars);
1692 #endif
1693         } else {
1694                 if (ctx->extract_flags & WIMLIB_EXTRACT_FLAG_REPLACE_INVALID_FILENAMES)
1695                 {
1696                         WARNING("\"%"TS"\" has an invalid filename "
1697                                 "that is not supported on this platform; "
1698                                 "extracting dummy name instead",
1699                                 dentry_full_path(dentry));
1700                         goto out_replace;
1701                 } else {
1702                         WARNING("Not extracting \"%"TS"\": has an invalid filename "
1703                                 "that is not supported on this platform",
1704                                 dentry_full_path(dentry));
1705                         goto skip_dentry;
1706                 }
1707         }
1708
1709 out_replace:
1710         {
1711                 utf16lechar utf16_name_copy[dentry->file_name_nbytes / 2];
1712
1713                 memcpy(utf16_name_copy, dentry->file_name, dentry->file_name_nbytes);
1714                 file_name_valid(utf16_name_copy, dentry->file_name_nbytes / 2, true);
1715
1716                 tchar *tchar_name;
1717                 size_t tchar_nchars;
1718         #ifdef __WIN32__
1719                 tchar_name = utf16_name_copy;
1720                 tchar_nchars = dentry->file_name_nbytes / 2;
1721         #else
1722                 ret = utf16le_to_tstr(utf16_name_copy,
1723                                       dentry->file_name_nbytes,
1724                                       &tchar_name, &tchar_nchars);
1725                 if (ret)
1726                         return ret;
1727         #endif
1728                 size_t fixed_name_num_chars = tchar_nchars;
1729                 tchar fixed_name[tchar_nchars + 50];
1730
1731                 tmemcpy(fixed_name, tchar_name, tchar_nchars);
1732                 fixed_name_num_chars += tsprintf(fixed_name + tchar_nchars,
1733                                                  T(" (invalid filename #%lu)"),
1734                                                  ++ctx->invalid_sequence);
1735         #ifndef __WIN32__
1736                 FREE(tchar_name);
1737         #endif
1738                 dentry->extraction_name = memdup(fixed_name,
1739                                                  2 * fixed_name_num_chars + 2);
1740                 if (!dentry->extraction_name)
1741                         return WIMLIB_ERR_NOMEM;
1742                 dentry->extraction_name_nchars = fixed_name_num_chars;
1743         }
1744         return 0;
1745
1746 skip_dentry:
1747         for_dentry_in_tree(dentry, dentry_mark_skipped, NULL);
1748         return 0;
1749 }
1750
1751 /* Clean up dentry and inode structure after extraction.  */
1752 static int
1753 dentry_reset_needs_extraction(struct wim_dentry *dentry, void *_ignore)
1754 {
1755         struct wim_inode *inode = dentry->d_inode;
1756
1757         dentry->in_extraction_tree = 0;
1758         dentry->extraction_skipped = 0;
1759         dentry->was_hardlinked = 0;
1760         dentry->skeleton_extracted = 0;
1761         inode->i_visited = 0;
1762         FREE(inode->i_extracted_file);
1763         inode->i_extracted_file = NULL;
1764         inode->i_dos_name_extracted = 0;
1765         if ((void*)dentry->extraction_name != (void*)dentry->file_name)
1766                 FREE(dentry->extraction_name);
1767         dentry->extraction_name = NULL;
1768         return 0;
1769 }
1770
1771 /* Tally features necessary to extract a dentry and the corresponding inode.  */
1772 static int
1773 dentry_tally_features(struct wim_dentry *dentry, void *_features)
1774 {
1775         struct wim_features *features = _features;
1776         struct wim_inode *inode = dentry->d_inode;
1777
1778         if (inode->i_attributes & FILE_ATTRIBUTE_ARCHIVE)
1779                 features->archive_files++;
1780         if (inode->i_attributes & FILE_ATTRIBUTE_HIDDEN)
1781                 features->hidden_files++;
1782         if (inode->i_attributes & FILE_ATTRIBUTE_SYSTEM)
1783                 features->system_files++;
1784         if (inode->i_attributes & FILE_ATTRIBUTE_COMPRESSED)
1785                 features->compressed_files++;
1786         if (inode->i_attributes & FILE_ATTRIBUTE_ENCRYPTED) {
1787                 if (inode->i_attributes & FILE_ATTRIBUTE_DIRECTORY)
1788                         features->encrypted_directories++;
1789                 else
1790                         features->encrypted_files++;
1791         }
1792         if (inode->i_attributes & FILE_ATTRIBUTE_NOT_CONTENT_INDEXED)
1793                 features->not_context_indexed_files++;
1794         if (inode->i_attributes & FILE_ATTRIBUTE_SPARSE_FILE)
1795                 features->sparse_files++;
1796         if (inode_has_named_stream(inode))
1797                 features->named_data_streams++;
1798         if (inode->i_visited)
1799                 features->hard_links++;
1800         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1801                 features->reparse_points++;
1802                 if (inode_is_symlink(inode))
1803                         features->symlink_reparse_points++;
1804                 else
1805                         features->other_reparse_points++;
1806         }
1807         if (inode->i_security_id != -1)
1808                 features->security_descriptors++;
1809         if (dentry->short_name_nbytes)
1810                 features->short_names++;
1811         if (inode_has_unix_data(inode))
1812                 features->unix_data++;
1813         inode->i_visited = 1;
1814         return 0;
1815 }
1816
1817 /* Tally the features necessary to extract a dentry tree.  */
1818 static void
1819 dentry_tree_get_features(struct wim_dentry *root, struct wim_features *features)
1820 {
1821         memset(features, 0, sizeof(struct wim_features));
1822         for_dentry_in_tree(root, dentry_tally_features, features);
1823         dentry_tree_clear_inode_visited(root);
1824 }
1825
1826 static u32
1827 compute_supported_attributes_mask(const struct wim_features *supported_features)
1828 {
1829         u32 mask = ~(u32)0;
1830
1831         if (!supported_features->archive_files)
1832                 mask &= ~FILE_ATTRIBUTE_ARCHIVE;
1833
1834         if (!supported_features->hidden_files)
1835                 mask &= ~FILE_ATTRIBUTE_HIDDEN;
1836
1837         if (!supported_features->system_files)
1838                 mask &= ~FILE_ATTRIBUTE_SYSTEM;
1839
1840         if (!supported_features->not_context_indexed_files)
1841                 mask &= ~FILE_ATTRIBUTE_NOT_CONTENT_INDEXED;
1842
1843         if (!supported_features->compressed_files)
1844                 mask &= ~FILE_ATTRIBUTE_COMPRESSED;
1845
1846         if (!supported_features->sparse_files)
1847                 mask &= ~FILE_ATTRIBUTE_SPARSE_FILE;
1848
1849         if (!supported_features->reparse_points)
1850                 mask &= ~FILE_ATTRIBUTE_REPARSE_POINT;
1851
1852         return mask;
1853 }
1854
1855 static int
1856 do_feature_check(const struct wim_features *required_features,
1857                  const struct wim_features *supported_features,
1858                  int extract_flags,
1859                  const struct apply_operations *ops,
1860                  const tchar *wim_source_path)
1861 {
1862         const tchar *loc;
1863         const tchar *mode = T("this extraction mode");
1864
1865         if (wim_source_path[0] == '\0')
1866                 loc = T("the WIM image");
1867         else
1868                 loc = wim_source_path;
1869
1870         /* We're an archive program, so theoretically we can do what we want
1871          * with FILE_ATTRIBUTE_ARCHIVE (which is a dumb flag anyway).  Don't
1872          * bother the user about it.  */
1873 #if 0
1874         if (required_features->archive_files && !supported_features->archive_files)
1875         {
1876                 WARNING(
1877           "%lu files in %"TS" are marked as archived, but this attribute\n"
1878 "          is not supported in %"TS".",
1879                         required_features->archive_files, loc, mode);
1880         }
1881 #endif
1882
1883         if (required_features->hidden_files && !supported_features->hidden_files)
1884         {
1885                 WARNING(
1886           "%lu files in %"TS" are marked as hidden, but this\n"
1887 "          attribute is not supported in %"TS".",
1888                         required_features->hidden_files, loc, mode);
1889         }
1890
1891         if (required_features->system_files && !supported_features->system_files)
1892         {
1893                 WARNING(
1894           "%lu files in %"TS" are marked as system files,\n"
1895 "          but this attribute is not supported in %"TS".",
1896                         required_features->system_files, loc, mode);
1897         }
1898
1899         if (required_features->compressed_files && !supported_features->compressed_files)
1900         {
1901                 WARNING(
1902           "%lu files in %"TS" are marked as being transparently\n"
1903 "          compressed, but transparent compression is not supported in\n"
1904 "          %"TS".  These files will be extracted as uncompressed.",
1905                         required_features->compressed_files, loc, mode);
1906         }
1907
1908         if (required_features->encrypted_files && !supported_features->encrypted_files)
1909         {
1910                 WARNING(
1911           "%lu files in %"TS" are marked as being encrypted,\n"
1912 "           but encryption is not supported in %"TS".  These files\n"
1913 "           will not be extracted.",
1914                         required_features->encrypted_files, loc, mode);
1915         }
1916
1917         if (required_features->encrypted_directories &&
1918             !supported_features->encrypted_directories)
1919         {
1920                 WARNING(
1921           "%lu directories in %"TS" are marked as being encrypted,\n"
1922 "           but encryption is not supported in %"TS".\n"
1923 "           These directories will be extracted as unencrypted.",
1924                         required_features->encrypted_directories, loc, mode);
1925         }
1926
1927         if (required_features->not_context_indexed_files &&
1928             !supported_features->not_context_indexed_files)
1929         {
1930                 WARNING(
1931           "%lu files in %"TS" are marked as not content indexed,\n"
1932 "          but this attribute is not supported in %"TS".",
1933                         required_features->not_context_indexed_files, loc, mode);
1934         }
1935
1936         if (required_features->sparse_files && !supported_features->sparse_files)
1937         {
1938                 WARNING(
1939           "%lu files in %"TS" are marked as sparse, but creating\n"
1940 "           sparse files is not supported in %"TS".  These files\n"
1941 "           will be extracted as non-sparse.",
1942                         required_features->sparse_files, loc, mode);
1943         }
1944
1945         if (required_features->named_data_streams &&
1946             !supported_features->named_data_streams)
1947         {
1948                 WARNING(
1949           "%lu files in %"TS" contain one or more alternate (named)\n"
1950 "          data streams, which are not supported in %"TS".\n"
1951 "          Alternate data streams will NOT be extracted.",
1952                         required_features->named_data_streams, loc, mode);
1953         }
1954
1955         if (unlikely(extract_flags & (WIMLIB_EXTRACT_FLAG_HARDLINK |
1956                                       WIMLIB_EXTRACT_FLAG_SYMLINK)) &&
1957             required_features->named_data_streams &&
1958             supported_features->named_data_streams)
1959         {
1960                 WARNING(
1961           "%lu files in %"TS" contain one or more alternate (named)\n"
1962 "          data streams, which are not supported in linked extraction mode.\n"
1963 "          Alternate data streams will NOT be extracted.",
1964                         required_features->named_data_streams, loc);
1965         }
1966
1967         if (required_features->hard_links && !supported_features->hard_links)
1968         {
1969                 WARNING(
1970           "%lu files in %"TS" are hard links, but hard links are\n"
1971 "          not supported in %"TS".  Hard links will be extracted as\n"
1972 "          duplicate copies of the linked files.",
1973                         required_features->hard_links, loc, mode);
1974         }
1975
1976         if (required_features->reparse_points && !supported_features->reparse_points)
1977         {
1978                 if (supported_features->symlink_reparse_points) {
1979                         if (required_features->other_reparse_points) {
1980                                 WARNING(
1981           "%lu files in %"TS" are reparse points that are neither\n"
1982 "          symbolic links nor junction points and are not supported in\n"
1983 "          %"TS".  These reparse points will not be extracted.",
1984                                         required_features->other_reparse_points, loc,
1985                                         mode);
1986                         }
1987                 } else {
1988                         WARNING(
1989           "%lu files in %"TS" are reparse points, which are\n"
1990 "          not supported in %"TS" and will not be extracted.",
1991                                 required_features->reparse_points, loc, mode);
1992                 }
1993         }
1994
1995         if (required_features->security_descriptors &&
1996             !supported_features->security_descriptors)
1997         {
1998                 WARNING(
1999           "%lu files in %"TS" have Windows NT security descriptors,\n"
2000 "          but extracting security descriptors is not supported in\n"
2001 "          %"TS".  No security descriptors will be extracted.",
2002                         required_features->security_descriptors, loc, mode);
2003         }
2004
2005         if (required_features->short_names && !supported_features->short_names)
2006         {
2007                 WARNING(
2008           "%lu files in %"TS" have short (DOS) names, but\n"
2009 "          extracting short names is not supported in %"TS".\n"
2010 "          Short names will not be extracted.\n",
2011                         required_features->short_names, loc, mode);
2012         }
2013
2014         if ((extract_flags & WIMLIB_EXTRACT_FLAG_UNIX_DATA) &&
2015             required_features->unix_data && !supported_features->unix_data)
2016         {
2017                 ERROR("Extracting UNIX data is not supported in %"TS, mode);
2018                 return WIMLIB_ERR_UNSUPPORTED;
2019         }
2020         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SHORT_NAMES) &&
2021             required_features->short_names && !supported_features->short_names)
2022         {
2023                 ERROR("Extracting short names is not supported in %"TS"", mode);
2024                 return WIMLIB_ERR_UNSUPPORTED;
2025         }
2026         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_TIMESTAMPS) &&
2027             !ops->set_timestamps)
2028         {
2029                 ERROR("Extracting timestamps is not supported in %"TS"", mode);
2030                 return WIMLIB_ERR_UNSUPPORTED;
2031         }
2032         if (((extract_flags & (WIMLIB_EXTRACT_FLAG_STRICT_ACLS |
2033                                WIMLIB_EXTRACT_FLAG_UNIX_DATA))
2034              == WIMLIB_EXTRACT_FLAG_STRICT_ACLS) &&
2035             required_features->security_descriptors &&
2036             !supported_features->security_descriptors)
2037         {
2038                 ERROR("Extracting security descriptors is not supported in %"TS, mode);
2039                 return WIMLIB_ERR_UNSUPPORTED;
2040         }
2041
2042         if ((extract_flags & WIMLIB_EXTRACT_FLAG_HARDLINK) &&
2043             !supported_features->hard_links)
2044         {
2045                 ERROR("Hard link extraction mode requested, but "
2046                       "%"TS" does not support hard links!", mode);
2047                 return WIMLIB_ERR_UNSUPPORTED;
2048         }
2049
2050         if ((extract_flags & WIMLIB_EXTRACT_FLAG_STRICT_SYMLINKS) &&
2051             required_features->symlink_reparse_points &&
2052             !(supported_features->symlink_reparse_points ||
2053               supported_features->reparse_points))
2054         {
2055                 ERROR("Extracting symbolic links is not supported in %"TS, mode);
2056                 return WIMLIB_ERR_UNSUPPORTED;
2057         }
2058
2059         if ((extract_flags & WIMLIB_EXTRACT_FLAG_SYMLINK) &&
2060             !supported_features->symlink_reparse_points)
2061         {
2062                 ERROR("Symbolic link extraction mode requested, but "
2063                       "%"TS" does not support symbolic "
2064                       "links!", mode);
2065                 return WIMLIB_ERR_UNSUPPORTED;
2066         }
2067         return 0;
2068 }
2069
2070 static void
2071 do_extract_warnings(struct apply_ctx *ctx)
2072 {
2073         if (ctx->partial_security_descriptors == 0 &&
2074             ctx->no_security_descriptors == 0)
2075                 return;
2076
2077         WARNING("Extraction to \"%"TS"\" complete, but with one or more warnings:",
2078                 ctx->target);
2079         if (ctx->partial_security_descriptors != 0) {
2080                 WARNING("- Could only partially set the security descriptor\n"
2081                         "            on %lu files or directories.",
2082                         ctx->partial_security_descriptors);
2083         }
2084         if (ctx->no_security_descriptors != 0) {
2085                 WARNING("- Could not set security descriptor at all\n"
2086                         "            on %lu files or directories.",
2087                         ctx->no_security_descriptors);
2088         }
2089 #ifdef __WIN32__
2090         WARNING("To fully restore all security descriptors, run the program\n"
2091                 "          with Administrator rights.");
2092 #endif
2093 }
2094
2095 /*
2096  * extract_tree - Extract a file or directory tree from the currently selected
2097  *                WIM image.
2098  *
2099  * @wim:        WIMStruct for the WIM file, with the desired image selected
2100  *              (as wim->current_image).
2101  *
2102  * @wim_source_path:
2103  *              "Canonical" (i.e. no leading or trailing slashes, path
2104  *              separators WIM_PATH_SEPARATOR) path inside the WIM image to
2105  *              extract.  An empty string means the full image.
2106  *
2107  * @target:
2108  *              Filesystem path to extract the file or directory tree to.
2109  *              (Or, with WIMLIB_EXTRACT_FLAG_NTFS: the name of a NTFS volume.)
2110  *
2111  * @extract_flags:
2112  *              WIMLIB_EXTRACT_FLAG_*.  Also, the private flag
2113  *              WIMLIB_EXTRACT_FLAG_MULTI_IMAGE will be set if this is being
2114  *              called through wimlib_extract_image() with WIMLIB_ALL_IMAGES as
2115  *              the image.
2116  *
2117  * @progress_func:
2118  *              If non-NULL, progress function for the extraction.  The messages
2119  *              that may be sent in this function are:
2120  *
2121  *              WIMLIB_PROGRESS_MSG_EXTRACT_TREE_BEGIN or
2122  *                      WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN;
2123  *              WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_BEGIN;
2124  *              WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_END;
2125  *              WIMLIB_PROGRESS_MSG_EXTRACT_DENTRY;
2126  *              WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS;
2127  *              WIMLIB_PROGRESS_MSG_APPLY_TIMESTAMPS;
2128  *              WIMLIB_PROGRESS_MSG_EXTRACT_TREE_END or
2129  *                      WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END.
2130  *
2131  * Returns 0 on success; a positive WIMLIB_ERR_* code on failure.
2132  */
2133 static int
2134 extract_tree(WIMStruct *wim, const tchar *wim_source_path, const tchar *target,
2135              int extract_flags, wimlib_progress_func_t progress_func)
2136 {
2137         struct wim_dentry *root;
2138         struct wim_features required_features;
2139         struct apply_ctx ctx;
2140         int ret;
2141         struct wim_lookup_table_entry *lte;
2142
2143         /* Start initializing the apply_ctx.  */
2144         memset(&ctx, 0, sizeof(struct apply_ctx));
2145         ctx.wim = wim;
2146         ctx.extract_flags = extract_flags;
2147         ctx.target = target;
2148         ctx.target_nchars = tstrlen(target);
2149         ctx.progress_func = progress_func;
2150         if (progress_func) {
2151                 ctx.progress.extract.wimfile_name = wim->filename;
2152                 ctx.progress.extract.image = wim->current_image;
2153                 ctx.progress.extract.extract_flags = (extract_flags &
2154                                                       WIMLIB_EXTRACT_MASK_PUBLIC);
2155                 ctx.progress.extract.image_name = wimlib_get_image_name(wim,
2156                                                                         wim->current_image);
2157                 ctx.progress.extract.extract_root_wim_source_path = wim_source_path;
2158                 ctx.progress.extract.target = target;
2159         }
2160         INIT_LIST_HEAD(&ctx.stream_list);
2161
2162         /* Translate the path to extract into the corresponding
2163          * `struct wim_dentry', which will be the root of the
2164          * "dentry tree" to extract.  */
2165         root = get_dentry(wim, wim_source_path);
2166         if (!root) {
2167                 ERROR("Path \"%"TS"\" does not exist in WIM image %d",
2168                       wim_source_path, wim->current_image);
2169                 ret = WIMLIB_ERR_PATH_DOES_NOT_EXIST;
2170                 goto out;
2171         }
2172
2173         ctx.extract_root = root;
2174
2175         /* Select the appropriate apply_operations based on the
2176          * platform and extract_flags.  */
2177 #ifdef __WIN32__
2178         ctx.ops = &win32_apply_ops;
2179 #else
2180         ctx.ops = &unix_apply_ops;
2181 #endif
2182
2183 #ifdef WITH_NTFS_3G
2184         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS)
2185                 ctx.ops = &ntfs_3g_apply_ops;
2186 #endif
2187
2188         /* Call the start_extract() callback.  This gives the apply_operations
2189          * implementation a chance to do any setup needed to access the volume.
2190          * Furthermore, it's expected to set the supported features of this
2191          * extraction mode (ctx.supported_features), which are determined at
2192          * runtime as they may vary depending on the actual volume.  These
2193          * features are then compared with the actual features extracting this
2194          * dentry tree requires.  Some mismatches will merely produce warnings
2195          * and the unsupported data will be ignored; others will produce errors.
2196          */
2197         ret = ctx.ops->start_extract(target, &ctx);
2198         if (ret)
2199                 goto out;
2200
2201         dentry_tree_get_features(root, &required_features);
2202         ret = do_feature_check(&required_features, &ctx.supported_features,
2203                                extract_flags, ctx.ops, wim_source_path);
2204         if (ret)
2205                 goto out_finish_or_abort_extract;
2206
2207         ctx.supported_attributes_mask =
2208                 compute_supported_attributes_mask(&ctx.supported_features);
2209
2210         /* Figure out whether the root dentry is being extracted to the root of
2211          * a volume and therefore needs to be treated "specially", for example
2212          * not being explicitly created and not having attributes set.  */
2213         if (ctx.ops->target_is_root && ctx.ops->root_directory_is_special)
2214                 ctx.root_dentry_is_special = ctx.ops->target_is_root(target);
2215
2216         /* Calculate the actual filename component of each extracted dentry.  In
2217          * the process, set the dentry->extraction_skipped flag on dentries that
2218          * are being skipped for some reason (e.g. invalid filename).  */
2219         ret = for_dentry_in_tree(root, dentry_calculate_extraction_path, &ctx);
2220         if (ret)
2221                 goto out_dentry_reset_needs_extraction;
2222
2223         /* Build the list of the streams that need to be extracted and
2224          * initialize ctx.progress.extract with stream information.  */
2225         ret = for_dentry_in_tree(ctx.extract_root,
2226                                  dentry_resolve_and_zero_lte_refcnt, &ctx);
2227         if (ret)
2228                 goto out_dentry_reset_needs_extraction;
2229
2230         ret = for_dentry_in_tree(ctx.extract_root,
2231                                  dentry_add_streams_to_extract, &ctx);
2232         if (ret)
2233                 goto out_teardown_stream_list;
2234
2235         if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE) {
2236                 /* When extracting from a pipe, the number of bytes of data to
2237                  * extract can't be determined in the normal way (examining the
2238                  * lookup table), since at this point all we have is a set of
2239                  * SHA1 message digests of streams that need to be extracted.
2240                  * However, we can get a reasonably accurate estimate by taking
2241                  * <TOTALBYTES> from the corresponding <IMAGE> in the WIM XML
2242                  * data.  This does assume that a full image is being extracted,
2243                  * but currently there is no API for doing otherwise.  (Also,
2244                  * subtract <HARDLINKBYTES> from this if hard links are
2245                  * supported by the extraction mode.)  */
2246                 ctx.progress.extract.total_bytes =
2247                         wim_info_get_image_total_bytes(wim->wim_info,
2248                                                        wim->current_image);
2249                 if (ctx.supported_features.hard_links) {
2250                         ctx.progress.extract.total_bytes -=
2251                                 wim_info_get_image_hard_link_bytes(wim->wim_info,
2252                                                                    wim->current_image);
2253                 }
2254         }
2255
2256         /* Handle the special case of extracting a file to standard
2257          * output.  In that case, "root" should be a single file, not a
2258          * directory tree.  (If not, extract_dentry_to_stdout() will
2259          * return an error.)  */
2260         if (extract_flags & WIMLIB_EXTRACT_FLAG_TO_STDOUT) {
2261                 ret = extract_dentry_to_stdout(root);
2262                 goto out_teardown_stream_list;
2263         }
2264
2265         /* If a sequential extraction was specified, sort the streams to be
2266          * extracted by their position in the WIM file so that the WIM file can
2267          * be read sequentially.  */
2268         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_SEQUENTIAL |
2269                               WIMLIB_EXTRACT_FLAG_FROM_PIPE))
2270                                         == WIMLIB_EXTRACT_FLAG_SEQUENTIAL)
2271         {
2272                 ret = sort_stream_list_by_sequential_order(
2273                                 &ctx.stream_list,
2274                                 offsetof(struct wim_lookup_table_entry,
2275                                          extraction_list));
2276                 if (ret)
2277                         goto out_teardown_stream_list;
2278         }
2279
2280         if (ctx.ops->realpath_works_on_nonexisting_files &&
2281             ((extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) ||
2282              ctx.ops->requires_realtarget_in_paths))
2283         {
2284                 ctx.realtarget = realpath(target, NULL);
2285                 if (!ctx.realtarget) {
2286                         ret = WIMLIB_ERR_NOMEM;
2287                         goto out_teardown_stream_list;
2288                 }
2289                 ctx.realtarget_nchars = tstrlen(ctx.realtarget);
2290         }
2291
2292         if (progress_func) {
2293                 progress_func(*wim_source_path ? WIMLIB_PROGRESS_MSG_EXTRACT_TREE_BEGIN :
2294                                                  WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_BEGIN,
2295                               &ctx.progress);
2296         }
2297
2298         if (!ctx.root_dentry_is_special)
2299         {
2300                 tchar path[ctx.ops->path_max];
2301                 if (build_extraction_path(path, root, &ctx))
2302                 {
2303                         ret = extract_inode(path, &ctx, root->d_inode);
2304                         if (ret)
2305                                 goto out_free_realtarget;
2306                 }
2307         }
2308
2309         /* If we need to fix up the targets of absolute symbolic links
2310          * (WIMLIB_EXTRACT_FLAG_RPFIX) or the extraction mode requires paths to
2311          * be absolute, use realpath() (or its replacement on Windows) to get
2312          * the absolute path to the extraction target.  Note that this requires
2313          * the target directory to exist, unless
2314          * realpath_works_on_nonexisting_files is set in the apply_operations.
2315          * */
2316         if (!ctx.realtarget &&
2317             (((extract_flags & WIMLIB_EXTRACT_FLAG_RPFIX) &&
2318               required_features.symlink_reparse_points) ||
2319              ctx.ops->requires_realtarget_in_paths))
2320         {
2321                 ctx.realtarget = realpath(target, NULL);
2322                 if (!ctx.realtarget) {
2323                         ret = WIMLIB_ERR_NOMEM;
2324                         goto out_free_realtarget;
2325                 }
2326                 ctx.realtarget_nchars = tstrlen(ctx.realtarget);
2327         }
2328
2329         if (ctx.ops->requires_short_name_reordering) {
2330                 ret = for_dentry_in_tree(root, dentry_extract_dir_skeleton,
2331                                          &ctx);
2332                 if (ret)
2333                         goto out_free_realtarget;
2334         }
2335
2336         /* Finally, the important part: extract the tree of files.  */
2337         if (extract_flags & (WIMLIB_EXTRACT_FLAG_SEQUENTIAL |
2338                              WIMLIB_EXTRACT_FLAG_FROM_PIPE)) {
2339                 /* Sequential extraction requested, so two passes are needed
2340                  * (one for directory structure, one for streams.)  */
2341                 if (progress_func)
2342                         progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_BEGIN,
2343                                       &ctx.progress);
2344
2345                 if (!(extract_flags & WIMLIB_EXTRACT_FLAG_RESUME)) {
2346                         ret = for_dentry_in_tree(root, dentry_extract_skeleton, &ctx);
2347                         if (ret)
2348                                 goto out_free_realtarget;
2349                 }
2350                 if (progress_func)
2351                         progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_END,
2352                                       &ctx.progress);
2353                 if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE)
2354                         ret = extract_streams_from_pipe(&ctx);
2355                 else
2356                         ret = extract_stream_list(&ctx);
2357                 if (ret)
2358                         goto out_free_realtarget;
2359         } else {
2360                 /* Sequential extraction was not requested, so we can make do
2361                  * with one pass where we both create the files and extract
2362                  * streams.   */
2363                 if (progress_func)
2364                         progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_BEGIN,
2365                                       &ctx.progress);
2366                 ret = for_dentry_in_tree(root, dentry_extract, &ctx);
2367                 if (ret)
2368                         goto out_free_realtarget;
2369                 if (progress_func)
2370                         progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_DIR_STRUCTURE_END,
2371                                       &ctx.progress);
2372         }
2373
2374         /* If the total number of bytes to extract was miscalculated, just jump
2375          * to the calculated number in order to avoid confusing the progress
2376          * function.  This should only occur when extracting from a pipe.  */
2377         if (ctx.progress.extract.completed_bytes != ctx.progress.extract.total_bytes)
2378         {
2379                 DEBUG("Calculated %"PRIu64" bytes to extract, but actually "
2380                       "extracted %"PRIu64,
2381                       ctx.progress.extract.total_bytes,
2382                       ctx.progress.extract.completed_bytes);
2383         }
2384         if (progress_func &&
2385             ctx.progress.extract.completed_bytes < ctx.progress.extract.total_bytes)
2386         {
2387                 ctx.progress.extract.completed_bytes = ctx.progress.extract.total_bytes;
2388                 progress_func(WIMLIB_PROGRESS_MSG_EXTRACT_STREAMS, &ctx.progress);
2389         }
2390
2391         /* Apply security descriptors and timestamps.  This is done at the end,
2392          * and in a depth-first manner, to prevent timestamps from getting
2393          * changed by subsequent extract operations and to minimize the chance
2394          * of the restored security descriptors getting in our way.  */
2395         if (progress_func)
2396                 progress_func(WIMLIB_PROGRESS_MSG_APPLY_TIMESTAMPS,
2397                               &ctx.progress);
2398         ret = for_dentry_in_tree_depth(root, dentry_extract_final, &ctx);
2399         if (ret)
2400                 goto out_free_realtarget;
2401
2402         if (progress_func) {
2403                 progress_func(*wim_source_path ? WIMLIB_PROGRESS_MSG_EXTRACT_TREE_END :
2404                               WIMLIB_PROGRESS_MSG_EXTRACT_IMAGE_END,
2405                               &ctx.progress);
2406         }
2407
2408         do_extract_warnings(&ctx);
2409
2410         ret = 0;
2411 out_free_realtarget:
2412         FREE(ctx.realtarget);
2413 out_teardown_stream_list:
2414         /* Free memory allocated as part of the mapping from each
2415          * wim_lookup_table_entry to the dentries that reference it.  */
2416         if (ctx.extract_flags & WIMLIB_EXTRACT_FLAG_SEQUENTIAL)
2417                 list_for_each_entry(lte, &ctx.stream_list, extraction_list)
2418                         if (lte->out_refcnt > ARRAY_LEN(lte->inline_lte_dentries))
2419                                 FREE(lte->lte_dentries);
2420 out_dentry_reset_needs_extraction:
2421         for_dentry_in_tree(root, dentry_reset_needs_extraction, NULL);
2422 out_finish_or_abort_extract:
2423         if (ret) {
2424                 if (ctx.ops->abort_extract)
2425                         ctx.ops->abort_extract(&ctx);
2426         } else {
2427                 if (ctx.ops->finish_extract)
2428                         ret = ctx.ops->finish_extract(&ctx);
2429         }
2430 out:
2431         return ret;
2432 }
2433
2434 /* Validates a single wimlib_extract_command, mostly checking to make sure the
2435  * extract flags make sense. */
2436 static int
2437 check_extract_command(struct wimlib_extract_command *cmd, int wim_header_flags)
2438 {
2439         int extract_flags;
2440
2441         /* Empty destination path? */
2442         if (cmd->fs_dest_path[0] == T('\0'))
2443                 return WIMLIB_ERR_INVALID_PARAM;
2444
2445         extract_flags = cmd->extract_flags;
2446
2447         /* Check for invalid flag combinations  */
2448         if ((extract_flags &
2449              (WIMLIB_EXTRACT_FLAG_SYMLINK |
2450               WIMLIB_EXTRACT_FLAG_HARDLINK)) == (WIMLIB_EXTRACT_FLAG_SYMLINK |
2451                                                  WIMLIB_EXTRACT_FLAG_HARDLINK))
2452                 return WIMLIB_ERR_INVALID_PARAM;
2453
2454         if ((extract_flags &
2455              (WIMLIB_EXTRACT_FLAG_NO_ACLS |
2456               WIMLIB_EXTRACT_FLAG_STRICT_ACLS)) == (WIMLIB_EXTRACT_FLAG_NO_ACLS |
2457                                                     WIMLIB_EXTRACT_FLAG_STRICT_ACLS))
2458                 return WIMLIB_ERR_INVALID_PARAM;
2459
2460         if ((extract_flags &
2461              (WIMLIB_EXTRACT_FLAG_RPFIX |
2462               WIMLIB_EXTRACT_FLAG_NORPFIX)) == (WIMLIB_EXTRACT_FLAG_RPFIX |
2463                                                 WIMLIB_EXTRACT_FLAG_NORPFIX))
2464                 return WIMLIB_ERR_INVALID_PARAM;
2465
2466         if ((extract_flags &
2467              (WIMLIB_EXTRACT_FLAG_RESUME |
2468               WIMLIB_EXTRACT_FLAG_FROM_PIPE)) == WIMLIB_EXTRACT_FLAG_RESUME)
2469                 return WIMLIB_ERR_INVALID_PARAM;
2470
2471         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
2472 #ifndef WITH_NTFS_3G
2473                 ERROR("wimlib was compiled without support for NTFS-3g, so\n"
2474                       "        we cannot apply a WIM image directly to a NTFS volume.");
2475                 return WIMLIB_ERR_UNSUPPORTED;
2476 #endif
2477         }
2478
2479         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_RPFIX |
2480                               WIMLIB_EXTRACT_FLAG_NORPFIX)) == 0)
2481         {
2482                 /* Do reparse point fixups by default if the WIM header says
2483                  * they are enabled and we are extracting a full image. */
2484                 if (wim_header_flags & WIM_HDR_FLAG_RP_FIX)
2485                         extract_flags |= WIMLIB_EXTRACT_FLAG_RPFIX;
2486         }
2487
2488         /* TODO: Since UNIX data entries are stored in the file resources, in a
2489          * completely sequential extraction they may come up before the
2490          * corresponding file or symbolic link data.  This needs to be handled
2491          * better.  */
2492         if ((extract_flags & (WIMLIB_EXTRACT_FLAG_UNIX_DATA |
2493                               WIMLIB_EXTRACT_FLAG_SEQUENTIAL))
2494                                     == (WIMLIB_EXTRACT_FLAG_UNIX_DATA |
2495                                         WIMLIB_EXTRACT_FLAG_SEQUENTIAL))
2496         {
2497                 if (extract_flags & WIMLIB_EXTRACT_FLAG_FROM_PIPE) {
2498                         WARNING("Setting UNIX file/owner group may "
2499                                 "be impossible on some\n"
2500                                 "          symbolic links "
2501                                 "when applying from a pipe.");
2502                 } else {
2503                         extract_flags &= ~WIMLIB_EXTRACT_FLAG_SEQUENTIAL;
2504                         WARNING("Disabling sequential extraction for "
2505                                 "UNIX data mode");
2506                 }
2507         }
2508
2509         cmd->extract_flags = extract_flags;
2510         return 0;
2511 }
2512
2513
2514 /* Internal function to execute extraction commands for a WIM image.  The paths
2515  * in the extract commands are expected to be already "canonicalized".  */
2516 static int
2517 do_wimlib_extract_files(WIMStruct *wim,
2518                         int image,
2519                         struct wimlib_extract_command *cmds,
2520                         size_t num_cmds,
2521                         wimlib_progress_func_t progress_func)
2522 {
2523         int ret;
2524         bool found_link_cmd = false;
2525         bool found_nolink_cmd = false;
2526
2527         /* Select the image from which we are extracting files */
2528         ret = select_wim_image(wim, image);
2529         if (ret)
2530                 return ret;
2531
2532         /* Make sure there are no streams in the WIM that have not been
2533          * checksummed yet.  */
2534         ret = wim_checksum_unhashed_streams(wim);
2535         if (ret)
2536                 return ret;
2537
2538         /* Check for problems with the extraction commands */
2539         for (size_t i = 0; i < num_cmds; i++) {
2540                 ret = check_extract_command(&cmds[i], wim->hdr.flags);
2541                 if (ret)
2542                         return ret;
2543                 if (cmds[i].extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
2544                                              WIMLIB_EXTRACT_FLAG_HARDLINK)) {
2545                         found_link_cmd = true;
2546                 } else {
2547                         found_nolink_cmd = true;
2548                 }
2549                 if (found_link_cmd && found_nolink_cmd) {
2550                         ERROR("Symlink or hardlink extraction mode must "
2551                               "be set on all extraction commands");
2552                         return WIMLIB_ERR_INVALID_PARAM;
2553                 }
2554         }
2555
2556         /* Execute the extraction commands */
2557         for (size_t i = 0; i < num_cmds; i++) {
2558                 ret = extract_tree(wim,
2559                                    cmds[i].wim_source_path,
2560                                    cmds[i].fs_dest_path,
2561                                    cmds[i].extract_flags,
2562                                    progress_func);
2563                 if (ret)
2564                         return ret;
2565         }
2566         return 0;
2567 }
2568
2569 /* API function documented in wimlib.h  */
2570 WIMLIBAPI int
2571 wimlib_extract_files(WIMStruct *wim,
2572                      int image,
2573                      const struct wimlib_extract_command *cmds,
2574                      size_t num_cmds,
2575                      int default_extract_flags,
2576                      wimlib_progress_func_t progress_func)
2577 {
2578         int ret;
2579         struct wimlib_extract_command *cmds_copy;
2580         int all_flags = 0;
2581
2582         default_extract_flags &= WIMLIB_EXTRACT_MASK_PUBLIC;
2583
2584         if (num_cmds == 0)
2585                 return 0;
2586
2587         cmds_copy = CALLOC(num_cmds, sizeof(cmds[0]));
2588         if (!cmds_copy)
2589                 return WIMLIB_ERR_NOMEM;
2590
2591         for (size_t i = 0; i < num_cmds; i++) {
2592                 cmds_copy[i].extract_flags = (default_extract_flags |
2593                                                  cmds[i].extract_flags)
2594                                                 & WIMLIB_EXTRACT_MASK_PUBLIC;
2595                 all_flags |= cmds_copy[i].extract_flags;
2596
2597                 cmds_copy[i].wim_source_path = canonicalize_wim_path(cmds[i].wim_source_path);
2598                 if (!cmds_copy[i].wim_source_path) {
2599                         ret = WIMLIB_ERR_NOMEM;
2600                         goto out_free_cmds_copy;
2601                 }
2602
2603                 cmds_copy[i].fs_dest_path = canonicalize_fs_path(cmds[i].fs_dest_path);
2604                 if (!cmds_copy[i].fs_dest_path) {
2605                         ret = WIMLIB_ERR_NOMEM;
2606                         goto out_free_cmds_copy;
2607                 }
2608
2609         }
2610         ret = do_wimlib_extract_files(wim, image,
2611                                       cmds_copy, num_cmds,
2612                                       progress_func);
2613
2614         if (all_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
2615                          WIMLIB_EXTRACT_FLAG_HARDLINK))
2616         {
2617                 for_lookup_table_entry(wim->lookup_table,
2618                                        lte_free_extracted_file, NULL);
2619         }
2620 out_free_cmds_copy:
2621         for (size_t i = 0; i < num_cmds; i++) {
2622                 FREE(cmds_copy[i].wim_source_path);
2623                 FREE(cmds_copy[i].fs_dest_path);
2624         }
2625         FREE(cmds_copy);
2626         return ret;
2627 }
2628
2629 /*
2630  * Extracts an image from a WIM file.
2631  *
2632  * @wim:                WIMStruct for the WIM file.
2633  *
2634  * @image:              Number of the single image to extract.
2635  *
2636  * @target:             Directory or NTFS volume to extract the image to.
2637  *
2638  * @extract_flags:      Bitwise or of WIMLIB_EXTRACT_FLAG_*.
2639  *
2640  * @progress_func:      If non-NULL, a progress function to be called
2641  *                      periodically.
2642  *
2643  * Returns 0 on success; nonzero on failure.
2644  */
2645 static int
2646 extract_single_image(WIMStruct *wim, int image,
2647                      const tchar *target, int extract_flags,
2648                      wimlib_progress_func_t progress_func)
2649 {
2650         int ret;
2651         tchar *target_copy = canonicalize_fs_path(target);
2652         if (!target_copy)
2653                 return WIMLIB_ERR_NOMEM;
2654         struct wimlib_extract_command cmd = {
2655                 .wim_source_path = T(""),
2656                 .fs_dest_path = target_copy,
2657                 .extract_flags = extract_flags,
2658         };
2659         ret = do_wimlib_extract_files(wim, image, &cmd, 1, progress_func);
2660         FREE(target_copy);
2661         return ret;
2662 }
2663
2664 static const tchar * const filename_forbidden_chars =
2665 T(
2666 #ifdef __WIN32__
2667 "<>:\"/\\|?*"
2668 #else
2669 "/"
2670 #endif
2671 );
2672
2673 /* This function checks if it is okay to use a WIM image's name as a directory
2674  * name.  */
2675 static bool
2676 image_name_ok_as_dir(const tchar *image_name)
2677 {
2678         return image_name && *image_name &&
2679                 !tstrpbrk(image_name, filename_forbidden_chars) &&
2680                 tstrcmp(image_name, T(".")) &&
2681                 tstrcmp(image_name, T(".."));
2682 }
2683
2684 /* Extracts all images from the WIM to the directory @target, with the images
2685  * placed in subdirectories named by their image names. */
2686 static int
2687 extract_all_images(WIMStruct *wim,
2688                    const tchar *target,
2689                    int extract_flags,
2690                    wimlib_progress_func_t progress_func)
2691 {
2692         size_t image_name_max_len = max(xml_get_max_image_name_len(wim), 20);
2693         size_t output_path_len = tstrlen(target);
2694         tchar buf[output_path_len + 1 + image_name_max_len + 1];
2695         int ret;
2696         int image;
2697         const tchar *image_name;
2698         struct stat stbuf;
2699
2700         extract_flags |= WIMLIB_EXTRACT_FLAG_MULTI_IMAGE;
2701
2702         if (extract_flags & WIMLIB_EXTRACT_FLAG_NTFS) {
2703                 ERROR("Cannot extract multiple images in NTFS extraction mode.");
2704                 return WIMLIB_ERR_INVALID_PARAM;
2705         }
2706
2707         if (tstat(target, &stbuf)) {
2708                 if (errno == ENOENT) {
2709                         if (tmkdir(target, 0755)) {
2710                                 ERROR_WITH_ERRNO("Failed to create directory \"%"TS"\"", target);
2711                                 return WIMLIB_ERR_MKDIR;
2712                         }
2713                 } else {
2714                         ERROR_WITH_ERRNO("Failed to stat \"%"TS"\"", target);
2715                         return WIMLIB_ERR_STAT;
2716                 }
2717         } else if (!S_ISDIR(stbuf.st_mode)) {
2718                 ERROR("\"%"TS"\" is not a directory", target);
2719                 return WIMLIB_ERR_NOTDIR;
2720         }
2721
2722         tmemcpy(buf, target, output_path_len);
2723         buf[output_path_len] = OS_PREFERRED_PATH_SEPARATOR;
2724         for (image = 1; image <= wim->hdr.image_count; image++) {
2725                 image_name = wimlib_get_image_name(wim, image);
2726                 if (image_name_ok_as_dir(image_name)) {
2727                         tstrcpy(buf + output_path_len + 1, image_name);
2728                 } else {
2729                         /* Image name is empty or contains forbidden characters.
2730                          * Use image number instead. */
2731                         tsprintf(buf + output_path_len + 1, T("%d"), image);
2732                 }
2733                 ret = extract_single_image(wim, image, buf, extract_flags,
2734                                            progress_func);
2735                 if (ret)
2736                         return ret;
2737         }
2738         return 0;
2739 }
2740
2741 static int
2742 do_wimlib_extract_image(WIMStruct *wim,
2743                         int image,
2744                         const tchar *target,
2745                         int extract_flags,
2746                         wimlib_progress_func_t progress_func)
2747 {
2748         int ret;
2749
2750         if (image == WIMLIB_ALL_IMAGES) {
2751                 ret = extract_all_images(wim, target, extract_flags,
2752                                          progress_func);
2753         } else {
2754                 ret = extract_single_image(wim, image, target, extract_flags,
2755                                            progress_func);
2756         }
2757
2758         if (extract_flags & (WIMLIB_EXTRACT_FLAG_SYMLINK |
2759                              WIMLIB_EXTRACT_FLAG_HARDLINK))
2760         {
2761                 for_lookup_table_entry(wim->lookup_table,
2762                                        lte_free_extracted_file,
2763                                        NULL);
2764         }
2765         return ret;
2766 }
2767
2768 /* API function documented in wimlib.h  */
2769 WIMLIBAPI int
2770 wimlib_extract_image_from_pipe(int pipe_fd, const tchar *image_num_or_name,
2771                                const tchar *target, int extract_flags,
2772                                wimlib_progress_func_t progress_func)
2773 {
2774         int ret;
2775         WIMStruct *pwm;
2776         struct filedes *in_fd;
2777         int image;
2778         unsigned i;
2779
2780         extract_flags &= WIMLIB_EXTRACT_MASK_PUBLIC;
2781
2782         if (extract_flags & WIMLIB_EXTRACT_FLAG_TO_STDOUT)
2783                 return WIMLIB_ERR_INVALID_PARAM;
2784
2785         extract_flags |= WIMLIB_EXTRACT_FLAG_SEQUENTIAL;
2786
2787         /* Read the WIM header from the pipe and get a WIMStruct to represent
2788          * the pipable WIM.  Caveats:  Unlike getting a WIMStruct with
2789          * wimlib_open_wim(), getting a WIMStruct in this way will result in
2790          * an empty lookup table, no XML data read, and no filename set.  */
2791         ret = open_wim_as_WIMStruct(&pipe_fd,
2792                                     WIMLIB_OPEN_FLAG_FROM_PIPE,
2793                                     &pwm, progress_func);
2794         if (ret)
2795                 return ret;
2796
2797         /* Sanity check to make sure this is a pipable WIM.  */
2798         if (pwm->hdr.magic != PWM_MAGIC) {
2799                 ERROR("The WIM being read from file descriptor %d "
2800                       "is not pipable!", pipe_fd);
2801                 ret = WIMLIB_ERR_NOT_PIPABLE;
2802                 goto out_wimlib_free;
2803         }
2804
2805         /* Sanity check to make sure the first part of a pipable split WIM is
2806          * sent over the pipe first.  */
2807         if (pwm->hdr.part_number != 1) {
2808                 ERROR("The first part of the split WIM must be "
2809                       "sent over the pipe first.");
2810                 ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
2811                 goto out_wimlib_free;
2812         }
2813
2814         in_fd = &pwm->in_fd;
2815         wimlib_assert(in_fd->offset == WIM_HEADER_DISK_SIZE);
2816
2817         /* As mentioned, the WIMStruct we created from the pipe does not have
2818          * XML data yet.  Fix this by reading the extra copy of the XML data
2819          * that directly follows the header in pipable WIMs.  (Note: see
2820          * write_pipable_wim() for more details about the format of pipable
2821          * WIMs.)  */
2822         {
2823                 struct wim_lookup_table_entry xml_lte;
2824                 ret = read_pwm_stream_header(pwm, &xml_lte, 0, NULL);
2825                 if (ret)
2826                         goto out_wimlib_free;
2827
2828                 if (!(xml_lte.resource_entry.flags & WIM_RESHDR_FLAG_METADATA))
2829                 {
2830                         ERROR("Expected XML data, but found non-metadata "
2831                               "stream.");
2832                         ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
2833                         goto out_wimlib_free;
2834                 }
2835
2836                 copy_resource_entry(&pwm->hdr.xml_res_entry,
2837                                     &xml_lte.resource_entry);
2838
2839                 ret = read_wim_xml_data(pwm);
2840                 if (ret)
2841                         goto out_wimlib_free;
2842                 if (wim_info_get_num_images(pwm->wim_info) != pwm->hdr.image_count) {
2843                         ERROR("Image count in XML data is not the same as in WIM header.");
2844                         ret = WIMLIB_ERR_XML;
2845                         goto out_wimlib_free;
2846                 }
2847         }
2848
2849         /* Get image index (this may use the XML data that was just read to
2850          * resolve an image name).  */
2851         if (image_num_or_name) {
2852                 image = wimlib_resolve_image(pwm, image_num_or_name);
2853                 if (image == WIMLIB_NO_IMAGE) {
2854                         ERROR("\"%"TS"\" is not a valid image in the pipable WIM!",
2855                               image_num_or_name);
2856                         ret = WIMLIB_ERR_INVALID_IMAGE;
2857                         goto out_wimlib_free;
2858                 } else if (image == WIMLIB_ALL_IMAGES) {
2859                         ERROR("Applying all images from a pipe is not supported.");
2860                         ret = WIMLIB_ERR_INVALID_IMAGE;
2861                         goto out_wimlib_free;
2862                 }
2863         } else {
2864                 if (pwm->hdr.image_count != 1) {
2865                         ERROR("No image was specified, but the pipable WIM "
2866                               "did not contain exactly 1 image");
2867                         ret = WIMLIB_ERR_INVALID_IMAGE;
2868                         goto out_wimlib_free;
2869                 }
2870                 image = 1;
2871         }
2872
2873         /* Load the needed metadata resource.  */
2874         for (i = 1; i <= pwm->hdr.image_count; i++) {
2875                 struct wim_lookup_table_entry *metadata_lte;
2876                 struct wim_image_metadata *imd;
2877
2878                 metadata_lte = new_lookup_table_entry();
2879                 if (!metadata_lte) {
2880                         ret = WIMLIB_ERR_NOMEM;
2881                         goto out_wimlib_free;
2882                 }
2883
2884                 ret = read_pwm_stream_header(pwm, metadata_lte, 0, NULL);
2885                 imd = pwm->image_metadata[i - 1];
2886                 imd->metadata_lte = metadata_lte;
2887                 if (ret)
2888                         goto out_wimlib_free;
2889
2890                 if (!(metadata_lte->resource_entry.flags &
2891                       WIM_RESHDR_FLAG_METADATA))
2892                 {
2893                         ERROR("Expected metadata resource, but found "
2894                               "non-metadata stream.");
2895                         ret = WIMLIB_ERR_INVALID_PIPABLE_WIM;
2896                         goto out_wimlib_free;
2897                 }
2898
2899                 if (i == image) {
2900                         /* Metadata resource is for the images being extracted.
2901                          * Parse it and save the metadata in memory.  */
2902                         ret = read_metadata_resource(pwm, imd);
2903                         if (ret)
2904                                 goto out_wimlib_free;
2905                         imd->modified = 1;
2906                 } else {
2907                         /* Metadata resource is not for the image being
2908                          * extracted.  Skip over it.  */
2909                         ret = skip_pwm_stream(metadata_lte);
2910                         if (ret)
2911                                 goto out_wimlib_free;
2912                 }
2913         }
2914         /* Extract the image.  */
2915         extract_flags |= WIMLIB_EXTRACT_FLAG_FROM_PIPE;
2916         ret = do_wimlib_extract_image(pwm, image, target,
2917                                       extract_flags, progress_func);
2918         /* Clean up and return.  */
2919 out_wimlib_free:
2920         wimlib_free(pwm);
2921         return ret;
2922 }
2923
2924 /* API function documented in wimlib.h  */
2925 WIMLIBAPI int
2926 wimlib_extract_image(WIMStruct *wim,
2927                      int image,
2928                      const tchar *target,
2929                      int extract_flags,
2930                      wimlib_progress_func_t progress_func)
2931 {
2932         extract_flags &= WIMLIB_EXTRACT_MASK_PUBLIC;
2933         return do_wimlib_extract_image(wim, image, target, extract_flags,
2934                                        progress_func);
2935 }