wim_inode: Move file descriptors table into union
[wimlib] / src / dentry.c
1 /*
2  * dentry.c
3  *
4  * In the WIM file format, the dentries are stored in the "metadata resource"
5  * section right after the security data.  Each image in the WIM file has its
6  * own metadata resource with its own security data and dentry tree.  Dentries
7  * in different images may share file resources by referring to the same lookup
8  * table entries.
9  */
10
11 /*
12  * Copyright (C) 2012, 2013 Eric Biggers
13  *
14  * This file is part of wimlib, a library for working with WIM files.
15  *
16  * wimlib is free software; you can redistribute it and/or modify it under the
17  * terms of the GNU General Public License as published by the Free Software
18  * Foundation; either version 3 of the License, or (at your option) any later
19  * version.
20  *
21  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
22  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
23  * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
24  *
25  * You should have received a copy of the GNU General Public License along with
26  * wimlib; if not, see http://www.gnu.org/licenses/.
27  */
28
29 #ifdef HAVE_CONFIG_H
30 #  include "config.h"
31 #endif
32
33 #include "wimlib.h"
34 #include "wimlib/dentry.h"
35 #include "wimlib/encoding.h"
36 #include "wimlib/endianness.h"
37 #include "wimlib/error.h"
38 #include "wimlib/lookup_table.h"
39 #include "wimlib/metadata.h"
40 #include "wimlib/resource.h"
41 #include "wimlib/sha1.h"
42 #include "wimlib/timestamp.h"
43
44 #include <errno.h>
45
46 /* WIM alternate data stream entry (on-disk format) */
47 struct wim_ads_entry_on_disk {
48         /*  Length of the entry, in bytes.  This apparently includes all
49          *  fixed-length fields, plus the stream name and null terminator if
50          *  present, and the padding up to an 8 byte boundary.  wimlib is a
51          *  little less strict when reading the entries, and only requires that
52          *  the number of bytes from this field is at least as large as the size
53          *  of the fixed length fields and stream name without null terminator.
54          *  */
55         le64  length;
56
57         le64  reserved;
58
59         /* SHA1 message digest of the uncompressed stream; or, alternatively,
60          * can be all zeroes if the stream has zero length. */
61         u8 hash[SHA1_HASH_SIZE];
62
63         /* Length of the stream name, in bytes.  0 if the stream is unnamed.  */
64         le16 stream_name_nbytes;
65
66         /* Stream name in UTF-16LE.  It is @stream_name_nbytes bytes long,
67          * excluding the the null terminator.  There is a null terminator
68          * character if @stream_name_nbytes != 0; i.e., if this stream is named.
69          * */
70         utf16lechar stream_name[];
71 } _packed_attribute;
72
73 #define WIM_ADS_ENTRY_DISK_SIZE 38
74
75 /* On-disk format of a WIM dentry (directory entry), located in the metadata
76  * resource for a WIM image.  */
77 struct wim_dentry_on_disk {
78
79         /* Length of this directory entry in bytes, not including any alternate
80          * data stream entries.  Should be a multiple of 8 so that the following
81          * dentry or alternate data stream entry is aligned on an 8-byte
82          * boundary.  (If not, wimlib will round it up.)  It must be at least as
83          * long as the fixed-length fields of the dentry (WIM_DENTRY_DISK_SIZE),
84          * plus the lengths of the file name and/or short name if present.
85          *
86          * It is also possible for this field to be 0.  This situation, which is
87          * undocumented, indicates the end of a list of sibling nodes in a
88          * directory.  It also means the real length is 8, because the dentry
89          * included only the length field, but that takes up 8 bytes.  */
90         le64 length;
91
92         /* Attributes of the file or directory.  This is a bitwise OR of the
93          * FILE_ATTRIBUTE_* constants and should correspond to the value
94          * retrieved by GetFileAttributes() on Windows. */
95         le32 attributes;
96
97         /* A value that specifies the security descriptor for this file or
98          * directory.  If -1, the file or directory has no security descriptor.
99          * Otherwise, it is a 0-based index into the WIM image's table of
100          * security descriptors (see: `struct wim_security_data') */
101         sle32 security_id;
102
103         /* Offset, in bytes, from the start of the uncompressed metadata
104          * resource of this directory's child directory entries, or 0 if this
105          * directory entry does not correspond to a directory or otherwise does
106          * not have any children. */
107         le64 subdir_offset;
108
109         /* Reserved fields */
110         le64 unused_1;
111         le64 unused_2;
112
113
114         /* Creation time, last access time, and last write time, in
115          * 100-nanosecond intervals since 12:00 a.m UTC January 1, 1601.  They
116          * should correspond to the times gotten by calling GetFileTime() on
117          * Windows. */
118         le64 creation_time;
119         le64 last_access_time;
120         le64 last_write_time;
121
122         /* Vaguely, the SHA-1 message digest ("hash") of the file's contents.
123          * More specifically, this is for the "unnamed data stream" rather than
124          * any "alternate data streams".  This hash value is used to look up the
125          * corresponding entry in the WIM's stream lookup table to actually find
126          * the file contents within the WIM.
127          *
128          * If the file has no unnamed data stream (e.g. is a directory), then
129          * this field will be all zeroes.  If the unnamed data stream is empty
130          * (i.e. an "empty file"), then this field is also expected to be all
131          * zeroes.  (It will be if wimlib created the WIM image, at least;
132          * otherwise it can't be ruled out that the SHA-1 message digest of 0
133          * bytes of data is given explicitly.)
134          *
135          * If the file has reparse data, then this field will instead specify
136          * the SHA-1 message digest of the reparse data.  If it is somehow
137          * possible for a file to have both an unnamed data stream and reparse
138          * data, then this is not handled by wimlib.
139          *
140          * As a further special case, if this field is all zeroes but there is
141          * an alternate data stream entry with no name and a nonzero SHA-1
142          * message digest field, then that hash must be used instead of this
143          * one.  (wimlib does not use this quirk on WIM images it creates.)
144          */
145         u8 unnamed_stream_hash[SHA1_HASH_SIZE];
146
147         /* The format of the following data is not yet completely known and they
148          * do not correspond to Microsoft's documentation.
149          *
150          * If this directory entry is for a reparse point (has
151          * FILE_ATTRIBUTE_REPARSE_POINT set in the attributes field), then the
152          * version of the following fields containing the reparse tag is valid.
153          * Furthermore, the field notated as not_rpfixed, as far as I can tell,
154          * is supposed to be set to 1 if reparse point fixups (a.k.a. fixing the
155          * targets of absolute symbolic links) were *not* done, and otherwise 0.
156          *
157          * If this directory entry is not for a reparse point, then the version
158          * of the following fields containing the hard_link_group_id is valid.
159          * All MS says about this field is that "If this file is part of a hard
160          * link set, all the directory entries in the set will share the same
161          * value in this field.".  However, more specifically I have observed
162          * the following:
163          *    - If the file is part of a hard link set of size 1, then the
164          *    hard_link_group_id should be set to either 0, which is treated
165          *    specially as indicating "not hardlinked", or any unique value.
166          *    - The specific nonzero values used to identity hard link sets do
167          *    not matter, as long as they are unique.
168          *    - However, due to bugs in Microsoft's software, it is actually NOT
169          *    guaranteed that directory entries that share the same hard link
170          *    group ID are actually hard linked to each either.  We have to
171          *    handle this by using special code to use distinguishing features
172          *    (which is possible because some information about the underlying
173          *    inode is repeated in each dentry) to split up these fake hard link
174          *    groups into what they actually are supposed to be.
175          */
176         union {
177                 struct {
178                         le32 rp_unknown_1;
179                         le32 reparse_tag;
180                         le16 rp_unknown_2;
181                         le16 not_rpfixed;
182                 } _packed_attribute reparse;
183                 struct {
184                         le32 rp_unknown_1;
185                         le64 hard_link_group_id;
186                 } _packed_attribute nonreparse;
187         };
188
189         /* Number of alternate data stream entries that directly follow this
190          * dentry on-disk. */
191         le16 num_alternate_data_streams;
192
193         /* Length of this file's UTF-16LE encoded short name (8.3 DOS-compatible
194          * name), if present, in bytes, excluding the null terminator.  If this
195          * file has no short name, then this field should be 0.  */
196         le16 short_name_nbytes;
197
198         /* Length of this file's UTF-16LE encoded "long" name, excluding the
199          * null terminator.  If this file has no short name, then this field
200          * should be 0.  It's expected that only the root dentry has this field
201          * set to 0.  */
202         le16 file_name_nbytes;
203
204         /* Follewed by variable length file name, in UTF16-LE, if
205          * file_name_nbytes != 0.  Includes null terminator. */
206         /*utf16lechar file_name[];*/
207
208         /* Followed by variable length short name, in UTF16-LE, if
209          * short_name_nbytes != 0.  Includes null terminator. */
210         /*utf16lechar short_name[];*/
211 } _packed_attribute;
212
213 #define WIM_DENTRY_DISK_SIZE 102
214
215 /* Calculates the unaligned length, in bytes, of an on-disk WIM dentry that has
216  * a file name and short name that take the specified numbers of bytes.  This
217  * excludes any alternate data stream entries that may follow the dentry. */
218 static u64
219 _dentry_correct_length_unaligned(u16 file_name_nbytes, u16 short_name_nbytes)
220 {
221         u64 length = sizeof(struct wim_dentry_on_disk);
222         if (file_name_nbytes)
223                 length += file_name_nbytes + 2;
224         if (short_name_nbytes)
225                 length += short_name_nbytes + 2;
226         return length;
227 }
228
229 /* Calculates the unaligned length, in bytes, of an on-disk WIM dentry, based on
230  * the file name length and short name length.  Note that dentry->length is
231  * ignored; also, this excludes any alternate data stream entries that may
232  * follow the dentry. */
233 static u64
234 dentry_correct_length_unaligned(const struct wim_dentry *dentry)
235 {
236         return _dentry_correct_length_unaligned(dentry->file_name_nbytes,
237                                                 dentry->short_name_nbytes);
238 }
239
240 /* Duplicates a string of system-dependent encoding into a UTF-16LE string and
241  * returns the string and its length, in bytes, in the pointer arguments.  Frees
242  * any existing string at the return location before overwriting it. */
243 static int
244 get_utf16le_name(const tchar *name, utf16lechar **name_utf16le_ret,
245                  u16 *name_utf16le_nbytes_ret)
246 {
247         utf16lechar *name_utf16le;
248         size_t name_utf16le_nbytes;
249         int ret;
250 #if TCHAR_IS_UTF16LE
251         name_utf16le_nbytes = tstrlen(name) * sizeof(utf16lechar);
252         name_utf16le = MALLOC(name_utf16le_nbytes + sizeof(utf16lechar));
253         if (!name_utf16le)
254                 return WIMLIB_ERR_NOMEM;
255         memcpy(name_utf16le, name, name_utf16le_nbytes + sizeof(utf16lechar));
256         ret = 0;
257 #else
258
259         ret = tstr_to_utf16le(name, tstrlen(name), &name_utf16le,
260                               &name_utf16le_nbytes);
261         if (ret == 0) {
262                 if (name_utf16le_nbytes > 0xffff) {
263                         FREE(name_utf16le);
264                         ERROR("Multibyte string \"%"TS"\" is too long!", name);
265                         ret = WIMLIB_ERR_INVALID_UTF8_STRING;
266                 }
267         }
268 #endif
269         if (ret == 0) {
270                 FREE(*name_utf16le_ret);
271                 *name_utf16le_ret = name_utf16le;
272                 *name_utf16le_nbytes_ret = name_utf16le_nbytes;
273         }
274         return ret;
275 }
276
277 /* Sets the name of a WIM dentry from a multibyte string. */
278 int
279 set_dentry_name(struct wim_dentry *dentry, const tchar *new_name)
280 {
281         int ret;
282         ret = get_utf16le_name(new_name, &dentry->file_name,
283                                &dentry->file_name_nbytes);
284         if (ret == 0) {
285                 /* Clear the short name and recalculate the dentry length */
286                 if (dentry_has_short_name(dentry)) {
287                         FREE(dentry->short_name);
288                         dentry->short_name = NULL;
289                         dentry->short_name_nbytes = 0;
290                 }
291         }
292         return ret;
293 }
294
295 /* Returns the total length of a WIM alternate data stream entry on-disk,
296  * including the stream name, the null terminator, AND the padding after the
297  * entry to align the next ADS entry or dentry on an 8-byte boundary. */
298 static u64
299 ads_entry_total_length(const struct wim_ads_entry *entry)
300 {
301         u64 len = sizeof(struct wim_ads_entry_on_disk);
302         if (entry->stream_name_nbytes)
303                 len += entry->stream_name_nbytes + 2;
304         return (len + 7) & ~7;
305 }
306
307
308 static u64
309 _dentry_total_length(const struct wim_dentry *dentry, u64 length)
310 {
311         const struct wim_inode *inode = dentry->d_inode;
312         for (u16 i = 0; i < inode->i_num_ads; i++)
313                 length += ads_entry_total_length(&inode->i_ads_entries[i]);
314         return (length + 7) & ~7;
315 }
316
317 /* Calculate the aligned *total* length of an on-disk WIM dentry.  This includes
318  * all alternate data streams. */
319 u64
320 dentry_correct_total_length(const struct wim_dentry *dentry)
321 {
322         return _dentry_total_length(dentry,
323                                     dentry_correct_length_unaligned(dentry));
324 }
325
326 /* Like dentry_correct_total_length(), but use the existing dentry->length field
327  * instead of calculating its "correct" value. */
328 static u64
329 dentry_total_length(const struct wim_dentry *dentry)
330 {
331         return _dentry_total_length(dentry, dentry->length);
332 }
333
334 int
335 for_dentry_in_rbtree(struct rb_node *root,
336                      int (*visitor)(struct wim_dentry *, void *),
337                      void *arg)
338 {
339         int ret;
340         struct rb_node *node = root;
341         LIST_HEAD(stack);
342         while (1) {
343                 if (node) {
344                         list_add(&rbnode_dentry(node)->tmp_list, &stack);
345                         node = node->rb_left;
346                 } else {
347                         struct list_head *next;
348                         struct wim_dentry *dentry;
349
350                         next = stack.next;
351                         if (next == &stack)
352                                 return 0;
353                         dentry = container_of(next, struct wim_dentry, tmp_list);
354                         list_del(next);
355                         ret = visitor(dentry, arg);
356                         if (ret != 0)
357                                 return ret;
358                         node = dentry->rb_node.rb_right;
359                 }
360         }
361 }
362
363 static int
364 for_dentry_tree_in_rbtree_depth(struct rb_node *node,
365                                 int (*visitor)(struct wim_dentry*, void*),
366                                 void *arg)
367 {
368         int ret;
369         if (node) {
370                 ret = for_dentry_tree_in_rbtree_depth(node->rb_left,
371                                                       visitor, arg);
372                 if (ret != 0)
373                         return ret;
374                 ret = for_dentry_tree_in_rbtree_depth(node->rb_right,
375                                                       visitor, arg);
376                 if (ret != 0)
377                         return ret;
378                 ret = for_dentry_in_tree_depth(rbnode_dentry(node), visitor, arg);
379                 if (ret != 0)
380                         return ret;
381         }
382         return 0;
383 }
384
385 static int
386 for_dentry_tree_in_rbtree(struct rb_node *node,
387                           int (*visitor)(struct wim_dentry*, void*),
388                           void *arg)
389 {
390         int ret;
391         if (node) {
392                 ret = for_dentry_tree_in_rbtree(node->rb_left, visitor, arg);
393                 if (ret)
394                         return ret;
395                 ret = for_dentry_in_tree(rbnode_dentry(node), visitor, arg);
396                 if (ret)
397                         return ret;
398                 ret = for_dentry_tree_in_rbtree(node->rb_right, visitor, arg);
399                 if (ret)
400                         return ret;
401         }
402         return 0;
403 }
404
405 /* Calls a function on all directory entries in a WIM dentry tree.  Logically,
406  * this is a pre-order traversal (the function is called on a parent dentry
407  * before its children), but sibling dentries will be visited in order as well.
408  * */
409 int
410 for_dentry_in_tree(struct wim_dentry *root,
411                    int (*visitor)(struct wim_dentry*, void*), void *arg)
412 {
413         int ret;
414
415         if (!root)
416                 return 0;
417         ret = (*visitor)(root, arg);
418         if (ret)
419                 return ret;
420         return for_dentry_tree_in_rbtree(root->d_inode->i_children.rb_node,
421                                          visitor,
422                                          arg);
423 }
424
425 /* Like for_dentry_in_tree(), but the visitor function is always called on a
426  * dentry's children before on itself. */
427 int
428 for_dentry_in_tree_depth(struct wim_dentry *root,
429                          int (*visitor)(struct wim_dentry*, void*), void *arg)
430 {
431         int ret;
432
433         if (!root)
434                 return 0;
435         ret = for_dentry_tree_in_rbtree_depth(root->d_inode->i_children.rb_node,
436                                               visitor, arg);
437         if (ret)
438                 return ret;
439         return (*visitor)(root, arg);
440 }
441
442 /* Calculate the full path of @dentry.  The full path of its parent must have
443  * already been calculated, or it must be the root dentry. */
444 int
445 calculate_dentry_full_path(struct wim_dentry *dentry)
446 {
447         tchar *full_path;
448         u32 full_path_nbytes;
449         int ret;
450
451         if (dentry->_full_path)
452                 return 0;
453
454         if (dentry_is_root(dentry)) {
455                 static const tchar _root_path[] = {WIM_PATH_SEPARATOR, T('\0')};
456                 full_path = TSTRDUP(_root_path);
457                 if (!full_path)
458                         return WIMLIB_ERR_NOMEM;
459                 full_path_nbytes = 1 * sizeof(tchar);
460         } else {
461                 struct wim_dentry *parent;
462                 tchar *parent_full_path;
463                 u32 parent_full_path_nbytes;
464                 size_t filename_nbytes;
465
466                 parent = dentry->parent;
467                 if (dentry_is_root(parent)) {
468                         parent_full_path = T("");
469                         parent_full_path_nbytes = 0;
470                 } else {
471                         if (!parent->_full_path) {
472                                 ret = calculate_dentry_full_path(parent);
473                                 if (ret)
474                                         return ret;
475                         }
476                         parent_full_path = parent->_full_path;
477                         parent_full_path_nbytes = parent->full_path_nbytes;
478                 }
479
480                 /* Append this dentry's name as a tchar string to the full path
481                  * of the parent followed by the path separator */
482         #if TCHAR_IS_UTF16LE
483                 filename_nbytes = dentry->file_name_nbytes;
484         #else
485                 {
486                         int ret = utf16le_to_tstr_nbytes(dentry->file_name,
487                                                          dentry->file_name_nbytes,
488                                                          &filename_nbytes);
489                         if (ret)
490                                 return ret;
491                 }
492         #endif
493
494                 full_path_nbytes = parent_full_path_nbytes + sizeof(tchar) +
495                                    filename_nbytes;
496                 full_path = MALLOC(full_path_nbytes + sizeof(tchar));
497                 if (!full_path)
498                         return WIMLIB_ERR_NOMEM;
499                 memcpy(full_path, parent_full_path, parent_full_path_nbytes);
500                 full_path[parent_full_path_nbytes / sizeof(tchar)] = WIM_PATH_SEPARATOR;
501         #if TCHAR_IS_UTF16LE
502                 memcpy(&full_path[parent_full_path_nbytes / sizeof(tchar) + 1],
503                        dentry->file_name,
504                        filename_nbytes + sizeof(tchar));
505         #else
506                 utf16le_to_tstr_buf(dentry->file_name,
507                                     dentry->file_name_nbytes,
508                                     &full_path[parent_full_path_nbytes /
509                                                sizeof(tchar) + 1]);
510         #endif
511         }
512         dentry->_full_path = full_path;
513         dentry->full_path_nbytes= full_path_nbytes;
514         return 0;
515 }
516
517 static int
518 do_calculate_dentry_full_path(struct wim_dentry *dentry, void *_ignore)
519 {
520         return calculate_dentry_full_path(dentry);
521 }
522
523 int
524 calculate_dentry_tree_full_paths(struct wim_dentry *root)
525 {
526         return for_dentry_in_tree(root, do_calculate_dentry_full_path, NULL);
527 }
528
529 tchar *
530 dentry_full_path(struct wim_dentry *dentry)
531 {
532         calculate_dentry_full_path(dentry);
533         return dentry->_full_path;
534 }
535
536 static int
537 increment_subdir_offset(struct wim_dentry *dentry, void *subdir_offset_p)
538 {
539         *(u64*)subdir_offset_p += dentry_correct_total_length(dentry);
540         return 0;
541 }
542
543 static int
544 call_calculate_subdir_offsets(struct wim_dentry *dentry, void *subdir_offset_p)
545 {
546         calculate_subdir_offsets(dentry, subdir_offset_p);
547         return 0;
548 }
549
550 /*
551  * Recursively calculates the subdir offsets for a directory tree.
552  *
553  * @dentry:  The root of the directory tree.
554  * @subdir_offset_p:  The current subdirectory offset; i.e., the subdirectory
555  *                    offset for @dentry.
556  */
557 void
558 calculate_subdir_offsets(struct wim_dentry *dentry, u64 *subdir_offset_p)
559 {
560         struct rb_node *node;
561
562         dentry->subdir_offset = *subdir_offset_p;
563         node = dentry->d_inode->i_children.rb_node;
564         if (node) {
565                 /* Advance the subdir offset by the amount of space the children
566                  * of this dentry take up. */
567                 for_dentry_in_rbtree(node, increment_subdir_offset, subdir_offset_p);
568
569                 /* End-of-directory dentry on disk. */
570                 *subdir_offset_p += 8;
571
572                 /* Recursively call calculate_subdir_offsets() on all the
573                  * children. */
574                 for_dentry_in_rbtree(node, call_calculate_subdir_offsets, subdir_offset_p);
575         } else {
576                 /* On disk, childless directories have a valid subdir_offset
577                  * that points to an 8-byte end-of-directory dentry.  Regular
578                  * files or reparse points have a subdir_offset of 0. */
579                 if (dentry_is_directory(dentry))
580                         *subdir_offset_p += 8;
581                 else
582                         dentry->subdir_offset = 0;
583         }
584 }
585
586 /* Case-sensitive UTF-16LE dentry or stream name comparison.  Used on both UNIX
587  * (always) and Windows (sometimes) */
588 static int
589 compare_utf16le_names_case_sensitive(const utf16lechar *name1, size_t nbytes1,
590                                      const utf16lechar *name2, size_t nbytes2)
591 {
592         /* Return the result if the strings differ up to their minimum length.
593          * Note that we cannot use strcmp() or strncmp() here, as the strings
594          * are in UTF-16LE format. */
595         int result = memcmp(name1, name2, min(nbytes1, nbytes2));
596         if (result)
597                 return result;
598
599         /* The strings are the same up to their minimum length, so return a
600          * result based on their lengths. */
601         if (nbytes1 < nbytes2)
602                 return -1;
603         else if (nbytes1 > nbytes2)
604                 return 1;
605         else
606                 return 0;
607 }
608
609 #ifdef __WIN32__
610 /* Windoze: Case-insensitive UTF-16LE dentry or stream name comparison */
611 static int
612 compare_utf16le_names_case_insensitive(const utf16lechar *name1, size_t nbytes1,
613                                        const utf16lechar *name2, size_t nbytes2)
614 {
615         /* Return the result if the strings differ up to their minimum length.
616          * */
617         int result = _wcsnicmp((const wchar_t*)name1, (const wchar_t*)name2,
618                                min(nbytes1 / 2, nbytes2 / 2));
619         if (result)
620                 return result;
621
622         /* The strings are the same up to their minimum length, so return a
623          * result based on their lengths. */
624         if (nbytes1 < nbytes2)
625                 return -1;
626         else if (nbytes1 > nbytes2)
627                 return 1;
628         else
629                 return 0;
630 }
631 #endif /* __WIN32__ */
632
633 #ifdef __WIN32__
634 #  define compare_utf16le_names compare_utf16le_names_case_insensitive
635 #else
636 #  define compare_utf16le_names compare_utf16le_names_case_sensitive
637 #endif
638
639
640 #ifdef __WIN32__
641 static int
642 dentry_compare_names_case_insensitive(const struct wim_dentry *d1,
643                                       const struct wim_dentry *d2)
644 {
645         return compare_utf16le_names_case_insensitive(d1->file_name,
646                                                       d1->file_name_nbytes,
647                                                       d2->file_name,
648                                                       d2->file_name_nbytes);
649 }
650 #endif /* __WIN32__ */
651
652 static int
653 dentry_compare_names_case_sensitive(const struct wim_dentry *d1,
654                                     const struct wim_dentry *d2)
655 {
656         return compare_utf16le_names_case_sensitive(d1->file_name,
657                                                     d1->file_name_nbytes,
658                                                     d2->file_name,
659                                                     d2->file_name_nbytes);
660 }
661
662 #ifdef __WIN32__
663 #  define dentry_compare_names dentry_compare_names_case_insensitive
664 #else
665 #  define dentry_compare_names dentry_compare_names_case_sensitive
666 #endif
667
668 /* Return %true iff the alternate data stream entry @entry has the UTF-16LE
669  * stream name @name that has length @name_nbytes bytes. */
670 static inline bool
671 ads_entry_has_name(const struct wim_ads_entry *entry,
672                    const utf16lechar *name, size_t name_nbytes)
673 {
674         return !compare_utf16le_names(name, name_nbytes,
675                                       entry->stream_name,
676                                       entry->stream_name_nbytes);
677 }
678
679 /* Given a UTF-16LE filename and a directory, look up the dentry for the file.
680  * Return it if found, otherwise NULL.  This is case-sensitive on UNIX and
681  * case-insensitive on Windows. */
682 struct wim_dentry *
683 get_dentry_child_with_utf16le_name(const struct wim_dentry *dentry,
684                                    const utf16lechar *name,
685                                    size_t name_nbytes)
686 {
687         struct rb_node *node;
688
689 #ifdef __WIN32__
690         node = dentry->d_inode->i_children_case_insensitive.rb_node;
691 #else
692         node = dentry->d_inode->i_children.rb_node;
693 #endif
694
695         struct wim_dentry *child;
696         while (node) {
697         #ifdef __WIN32__
698                 child = rb_entry(node, struct wim_dentry, rb_node_case_insensitive);
699         #else
700                 child = rbnode_dentry(node);
701         #endif
702                 int result = compare_utf16le_names(name, name_nbytes,
703                                                    child->file_name,
704                                                    child->file_name_nbytes);
705                 if (result < 0)
706                         node = node->rb_left;
707                 else if (result > 0)
708                         node = node->rb_right;
709                 else {
710                 #ifdef __WIN32__
711                         if (!list_empty(&child->case_insensitive_conflict_list))
712                         {
713                                 WARNING("Result of case-insensitive lookup is ambiguous "
714                                         "(returning \"%ls\" instead of \"%ls\")",
715                                         child->file_name,
716                                         container_of(child->case_insensitive_conflict_list.next,
717                                                      struct wim_dentry,
718                                                      case_insensitive_conflict_list)->file_name);
719                         }
720                 #endif
721                         return child;
722                 }
723         }
724         return NULL;
725 }
726
727 /* Returns the child of @dentry that has the file name @name.  Returns NULL if
728  * no child has the name. */
729 struct wim_dentry *
730 get_dentry_child_with_name(const struct wim_dentry *dentry, const tchar *name)
731 {
732 #if TCHAR_IS_UTF16LE
733         return get_dentry_child_with_utf16le_name(dentry, name,
734                                                   tstrlen(name) * sizeof(tchar));
735 #else
736         utf16lechar *utf16le_name;
737         size_t utf16le_name_nbytes;
738         int ret;
739         struct wim_dentry *child;
740
741         ret = tstr_to_utf16le(name, tstrlen(name) * sizeof(tchar),
742                               &utf16le_name, &utf16le_name_nbytes);
743         if (ret) {
744                 child = NULL;
745         } else {
746                 child = get_dentry_child_with_utf16le_name(dentry,
747                                                            utf16le_name,
748                                                            utf16le_name_nbytes);
749                 FREE(utf16le_name);
750         }
751         return child;
752 #endif
753 }
754
755 static struct wim_dentry *
756 get_dentry_utf16le(WIMStruct *wim, const utf16lechar *path)
757 {
758         struct wim_dentry *cur_dentry, *parent_dentry;
759         const utf16lechar *p, *pp;
760
761         cur_dentry = parent_dentry = wim_root_dentry(wim);
762         if (!cur_dentry) {
763                 errno = ENOENT;
764                 return NULL;
765         }
766         p = path;
767         while (1) {
768                 while (*p == cpu_to_le16(WIM_PATH_SEPARATOR))
769                         p++;
770                 if (*p == cpu_to_le16('\0'))
771                         break;
772                 pp = p;
773                 while (*pp != cpu_to_le16(WIM_PATH_SEPARATOR) &&
774                        *pp != cpu_to_le16('\0'))
775                         pp++;
776
777                 cur_dentry = get_dentry_child_with_utf16le_name(parent_dentry, p,
778                                                                 (void*)pp - (void*)p);
779                 if (cur_dentry == NULL)
780                         break;
781                 p = pp;
782                 parent_dentry = cur_dentry;
783         }
784         if (cur_dentry == NULL) {
785                 if (dentry_is_directory(parent_dentry))
786                         errno = ENOENT;
787                 else
788                         errno = ENOTDIR;
789         }
790         return cur_dentry;
791 }
792
793 /* Returns the dentry corresponding to the @path, or NULL if there is no such
794  * dentry. */
795 struct wim_dentry *
796 get_dentry(WIMStruct *wim, const tchar *path)
797 {
798 #if TCHAR_IS_UTF16LE
799         return get_dentry_utf16le(wim, path);
800 #else
801         utf16lechar *path_utf16le;
802         size_t path_utf16le_nbytes;
803         int ret;
804         struct wim_dentry *dentry;
805
806         ret = tstr_to_utf16le(path, tstrlen(path) * sizeof(tchar),
807                               &path_utf16le, &path_utf16le_nbytes);
808         if (ret)
809                 return NULL;
810         dentry = get_dentry_utf16le(wim, path_utf16le);
811         FREE(path_utf16le);
812         return dentry;
813 #endif
814 }
815
816 struct wim_inode *
817 wim_pathname_to_inode(WIMStruct *wim, const tchar *path)
818 {
819         struct wim_dentry *dentry;
820         dentry = get_dentry(wim, path);
821         if (dentry)
822                 return dentry->d_inode;
823         else
824                 return NULL;
825 }
826
827 /* Takes in a path of length @len in @buf, and transforms it into a string for
828  * the path of its parent directory. */
829 static void
830 to_parent_name(tchar *buf, size_t len)
831 {
832         ssize_t i = (ssize_t)len - 1;
833         while (i >= 0 && buf[i] == WIM_PATH_SEPARATOR)
834                 i--;
835         while (i >= 0 && buf[i] != WIM_PATH_SEPARATOR)
836                 i--;
837         while (i >= 0 && buf[i] == WIM_PATH_SEPARATOR)
838                 i--;
839         buf[i + 1] = T('\0');
840 }
841
842 /* Returns the dentry that corresponds to the parent directory of @path, or NULL
843  * if the dentry is not found. */
844 struct wim_dentry *
845 get_parent_dentry(WIMStruct *wim, const tchar *path)
846 {
847         size_t path_len = tstrlen(path);
848         tchar buf[path_len + 1];
849
850         tmemcpy(buf, path, path_len + 1);
851         to_parent_name(buf, path_len);
852         return get_dentry(wim, buf);
853 }
854
855 /* Prints the full path of a dentry. */
856 int
857 print_dentry_full_path(struct wim_dentry *dentry, void *_ignore)
858 {
859         int ret = calculate_dentry_full_path(dentry);
860         if (ret)
861                 return ret;
862         tprintf(T("%"TS"\n"), dentry->_full_path);
863         return 0;
864 }
865
866 /* We want to be able to show the names of the file attribute flags that are
867  * set. */
868 struct file_attr_flag {
869         u32 flag;
870         const tchar *name;
871 };
872 struct file_attr_flag file_attr_flags[] = {
873         {FILE_ATTRIBUTE_READONLY,           T("READONLY")},
874         {FILE_ATTRIBUTE_HIDDEN,             T("HIDDEN")},
875         {FILE_ATTRIBUTE_SYSTEM,             T("SYSTEM")},
876         {FILE_ATTRIBUTE_DIRECTORY,          T("DIRECTORY")},
877         {FILE_ATTRIBUTE_ARCHIVE,            T("ARCHIVE")},
878         {FILE_ATTRIBUTE_DEVICE,             T("DEVICE")},
879         {FILE_ATTRIBUTE_NORMAL,             T("NORMAL")},
880         {FILE_ATTRIBUTE_TEMPORARY,          T("TEMPORARY")},
881         {FILE_ATTRIBUTE_SPARSE_FILE,        T("SPARSE_FILE")},
882         {FILE_ATTRIBUTE_REPARSE_POINT,      T("REPARSE_POINT")},
883         {FILE_ATTRIBUTE_COMPRESSED,         T("COMPRESSED")},
884         {FILE_ATTRIBUTE_OFFLINE,            T("OFFLINE")},
885         {FILE_ATTRIBUTE_NOT_CONTENT_INDEXED,T("NOT_CONTENT_INDEXED")},
886         {FILE_ATTRIBUTE_ENCRYPTED,          T("ENCRYPTED")},
887         {FILE_ATTRIBUTE_VIRTUAL,            T("VIRTUAL")},
888 };
889
890 /* Prints a directory entry.  @lookup_table is a pointer to the lookup table, if
891  * available.  If the dentry is unresolved and the lookup table is NULL, the
892  * lookup table entries will not be printed.  Otherwise, they will be. */
893 int
894 print_dentry(struct wim_dentry *dentry, void *lookup_table)
895 {
896         const u8 *hash;
897         struct wim_lookup_table_entry *lte;
898         const struct wim_inode *inode = dentry->d_inode;
899         tchar buf[50];
900
901         tprintf(T("[DENTRY]\n"));
902         tprintf(T("Length            = %"PRIu64"\n"), dentry->length);
903         tprintf(T("Attributes        = 0x%x\n"), inode->i_attributes);
904         for (size_t i = 0; i < ARRAY_LEN(file_attr_flags); i++)
905                 if (file_attr_flags[i].flag & inode->i_attributes)
906                         tprintf(T("    FILE_ATTRIBUTE_%"TS" is set\n"),
907                                 file_attr_flags[i].name);
908         tprintf(T("Security ID       = %d\n"), inode->i_security_id);
909         tprintf(T("Subdir offset     = %"PRIu64"\n"), dentry->subdir_offset);
910
911         wim_timestamp_to_str(inode->i_creation_time, buf, sizeof(buf));
912         tprintf(T("Creation Time     = %"TS"\n"), buf);
913
914         wim_timestamp_to_str(inode->i_last_access_time, buf, sizeof(buf));
915         tprintf(T("Last Access Time  = %"TS"\n"), buf);
916
917         wim_timestamp_to_str(inode->i_last_write_time, buf, sizeof(buf));
918         tprintf(T("Last Write Time   = %"TS"\n"), buf);
919
920         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
921                 tprintf(T("Reparse Tag       = 0x%"PRIx32"\n"), inode->i_reparse_tag);
922                 tprintf(T("Reparse Point Flags = 0x%"PRIx16"\n"),
923                         inode->i_not_rpfixed);
924                 tprintf(T("Reparse Point Unknown 2 = 0x%"PRIx32"\n"),
925                         inode->i_rp_unknown_2);
926         }
927         tprintf(T("Reparse Point Unknown 1 = 0x%"PRIx32"\n"),
928                 inode->i_rp_unknown_1);
929         tprintf(T("Hard Link Group   = 0x%"PRIx64"\n"), inode->i_ino);
930         tprintf(T("Hard Link Group Size = %"PRIu32"\n"), inode->i_nlink);
931         tprintf(T("Number of Alternate Data Streams = %hu\n"), inode->i_num_ads);
932         if (dentry_has_long_name(dentry))
933                 wimlib_printf(T("Filename = \"%"WS"\"\n"), dentry->file_name);
934         if (dentry_has_short_name(dentry))
935                 wimlib_printf(T("Short Name \"%"WS"\"\n"), dentry->short_name);
936         if (dentry->_full_path)
937                 tprintf(T("Full Path = \"%"TS"\"\n"), dentry->_full_path);
938
939         lte = inode_stream_lte(dentry->d_inode, 0, lookup_table);
940         if (lte) {
941                 print_lookup_table_entry(lte, stdout);
942         } else {
943                 hash = inode_stream_hash(inode, 0);
944                 if (hash) {
945                         tprintf(T("Hash              = 0x"));
946                         print_hash(hash, stdout);
947                         tputchar(T('\n'));
948                         tputchar(T('\n'));
949                 }
950         }
951         for (u16 i = 0; i < inode->i_num_ads; i++) {
952                 tprintf(T("[Alternate Stream Entry %u]\n"), i);
953                 wimlib_printf(T("Name = \"%"WS"\"\n"),
954                               inode->i_ads_entries[i].stream_name);
955                 tprintf(T("Name Length (UTF16 bytes) = %hu\n"),
956                        inode->i_ads_entries[i].stream_name_nbytes);
957                 hash = inode_stream_hash(inode, i + 1);
958                 if (hash) {
959                         tprintf(T("Hash              = 0x"));
960                         print_hash(hash, stdout);
961                         tputchar(T('\n'));
962                 }
963                 print_lookup_table_entry(inode_stream_lte(inode, i + 1, lookup_table),
964                                          stdout);
965         }
966         return 0;
967 }
968
969 /* Initializations done on every `struct wim_dentry'. */
970 static void
971 dentry_common_init(struct wim_dentry *dentry)
972 {
973         memset(dentry, 0, sizeof(struct wim_dentry));
974 }
975
976 struct wim_inode *
977 new_timeless_inode(void)
978 {
979         struct wim_inode *inode = CALLOC(1, sizeof(struct wim_inode));
980         if (inode) {
981                 inode->i_security_id = -1;
982                 inode->i_nlink = 1;
983                 inode->i_next_stream_id = 1;
984                 inode->i_not_rpfixed = 1;
985                 INIT_LIST_HEAD(&inode->i_list);
986                 INIT_LIST_HEAD(&inode->i_dentry);
987         }
988         return inode;
989 }
990
991 static struct wim_inode *
992 new_inode(void)
993 {
994         struct wim_inode *inode = new_timeless_inode();
995         if (inode) {
996                 u64 now = get_wim_timestamp();
997                 inode->i_creation_time = now;
998                 inode->i_last_access_time = now;
999                 inode->i_last_write_time = now;
1000         }
1001         return inode;
1002 }
1003
1004 /* Creates an unlinked directory entry. */
1005 int
1006 new_dentry(const tchar *name, struct wim_dentry **dentry_ret)
1007 {
1008         struct wim_dentry *dentry;
1009         int ret;
1010
1011         dentry = MALLOC(sizeof(struct wim_dentry));
1012         if (!dentry)
1013                 return WIMLIB_ERR_NOMEM;
1014
1015         dentry_common_init(dentry);
1016         ret = set_dentry_name(dentry, name);
1017         if (ret == 0) {
1018                 dentry->parent = dentry;
1019                 *dentry_ret = dentry;
1020         } else {
1021                 FREE(dentry);
1022                 ERROR("Failed to set name on new dentry with name \"%"TS"\"",
1023                       name);
1024         }
1025         return ret;
1026 }
1027
1028
1029 static int
1030 _new_dentry_with_inode(const tchar *name, struct wim_dentry **dentry_ret,
1031                         bool timeless)
1032 {
1033         struct wim_dentry *dentry;
1034         int ret;
1035
1036         ret = new_dentry(name, &dentry);
1037         if (ret)
1038                 return ret;
1039
1040         if (timeless)
1041                 dentry->d_inode = new_timeless_inode();
1042         else
1043                 dentry->d_inode = new_inode();
1044         if (!dentry->d_inode) {
1045                 free_dentry(dentry);
1046                 return WIMLIB_ERR_NOMEM;
1047         }
1048
1049         inode_add_dentry(dentry, dentry->d_inode);
1050         *dentry_ret = dentry;
1051         return 0;
1052 }
1053
1054 int
1055 new_dentry_with_timeless_inode(const tchar *name, struct wim_dentry **dentry_ret)
1056 {
1057         return _new_dentry_with_inode(name, dentry_ret, true);
1058 }
1059
1060 int
1061 new_dentry_with_inode(const tchar *name, struct wim_dentry **dentry_ret)
1062 {
1063         return _new_dentry_with_inode(name, dentry_ret, false);
1064 }
1065
1066 int
1067 new_filler_directory(const tchar *name, struct wim_dentry **dentry_ret)
1068 {
1069         int ret;
1070         struct wim_dentry *dentry;
1071
1072         DEBUG("Creating filler directory \"%"TS"\"", name);
1073         ret = new_dentry_with_inode(name, &dentry);
1074         if (ret)
1075                 return ret;
1076         /* Leave the inode number as 0; this is allowed for non
1077          * hard-linked files. */
1078         dentry->d_inode->i_resolved = 1;
1079         dentry->d_inode->i_attributes = FILE_ATTRIBUTE_DIRECTORY;
1080         *dentry_ret = dentry;
1081         return 0;
1082 }
1083
1084 static int
1085 init_ads_entry(struct wim_ads_entry *ads_entry, const void *name,
1086                size_t name_nbytes, bool is_utf16le)
1087 {
1088         int ret = 0;
1089         memset(ads_entry, 0, sizeof(*ads_entry));
1090
1091         if (is_utf16le) {
1092                 utf16lechar *p = MALLOC(name_nbytes + sizeof(utf16lechar));
1093                 if (!p)
1094                         return WIMLIB_ERR_NOMEM;
1095                 memcpy(p, name, name_nbytes);
1096                 p[name_nbytes / 2] = cpu_to_le16(0);
1097                 ads_entry->stream_name = p;
1098                 ads_entry->stream_name_nbytes = name_nbytes;
1099         } else {
1100                 if (name && *(const tchar*)name != T('\0')) {
1101                         ret = get_utf16le_name(name, &ads_entry->stream_name,
1102                                                &ads_entry->stream_name_nbytes);
1103                 }
1104         }
1105         return ret;
1106 }
1107
1108 static void
1109 destroy_ads_entry(struct wim_ads_entry *ads_entry)
1110 {
1111         FREE(ads_entry->stream_name);
1112 }
1113
1114 /* Frees an inode. */
1115 void
1116 free_inode(struct wim_inode *inode)
1117 {
1118         if (inode) {
1119                 if (inode->i_ads_entries) {
1120                         for (u16 i = 0; i < inode->i_num_ads; i++)
1121                                 destroy_ads_entry(&inode->i_ads_entries[i]);
1122                         FREE(inode->i_ads_entries);
1123                 }
1124                 /* HACK: This may instead delete the inode from i_list, but the
1125                  * hlist_del() behaves the same as list_del(). */
1126                 if (!hlist_unhashed(&inode->i_hlist))
1127                         hlist_del(&inode->i_hlist);
1128                 FREE(inode);
1129         }
1130 }
1131
1132 /* Decrements link count on an inode and frees it if the link count reaches 0.
1133  * */
1134 static void
1135 put_inode(struct wim_inode *inode)
1136 {
1137         wimlib_assert(inode->i_nlink != 0);
1138         if (--inode->i_nlink == 0) {
1139         #ifdef WITH_FUSE
1140                 if (inode->i_num_opened_fds == 0)
1141         #endif
1142                 {
1143                         free_inode(inode);
1144                 }
1145         }
1146 }
1147
1148 /* Frees a WIM dentry.
1149  *
1150  * The corresponding inode (if any) is freed only if its link count is
1151  * decremented to 0.
1152  */
1153 void
1154 free_dentry(struct wim_dentry *dentry)
1155 {
1156         if (dentry) {
1157                 FREE(dentry->file_name);
1158                 FREE(dentry->short_name);
1159                 FREE(dentry->_full_path);
1160                 if (dentry->d_inode)
1161                         put_inode(dentry->d_inode);
1162                 FREE(dentry);
1163         }
1164 }
1165
1166 /* This function is passed as an argument to for_dentry_in_tree_depth() in order
1167  * to free a directory tree. */
1168 static int
1169 do_free_dentry(struct wim_dentry *dentry, void *_lookup_table)
1170 {
1171         struct wim_lookup_table *lookup_table = _lookup_table;
1172
1173         if (lookup_table) {
1174                 struct wim_inode *inode = dentry->d_inode;
1175                 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1176                         struct wim_lookup_table_entry *lte;
1177
1178                         lte = inode_stream_lte(inode, i, lookup_table);
1179                         if (lte)
1180                                 lte_decrement_refcnt(lte, lookup_table);
1181                 }
1182         }
1183         free_dentry(dentry);
1184         return 0;
1185 }
1186
1187 /*
1188  * Unlinks and frees a dentry tree.
1189  *
1190  * @root:               The root of the tree.
1191  * @lookup_table:       The lookup table for dentries.  If non-NULL, the
1192  *                      reference counts in the lookup table for the lookup
1193  *                      table entries corresponding to the dentries will be
1194  *                      decremented.
1195  */
1196 void
1197 free_dentry_tree(struct wim_dentry *root, struct wim_lookup_table *lookup_table)
1198 {
1199         for_dentry_in_tree_depth(root, do_free_dentry, lookup_table);
1200 }
1201
1202 #ifdef __WIN32__
1203
1204 /* Insert a dentry into the case insensitive index for a directory.
1205  *
1206  * This is a red-black tree, but when multiple dentries share the same
1207  * case-insensitive name, only one is inserted into the tree itself; the rest
1208  * are connected in a list.
1209  */
1210 static struct wim_dentry *
1211 dentry_add_child_case_insensitive(struct wim_dentry *parent,
1212                                   struct wim_dentry *child)
1213 {
1214         struct rb_root *root;
1215         struct rb_node **new;
1216         struct rb_node *rb_parent;
1217
1218         root = &parent->d_inode->i_children_case_insensitive;
1219         new = &root->rb_node;
1220         rb_parent = NULL;
1221         while (*new) {
1222                 struct wim_dentry *this = container_of(*new, struct wim_dentry,
1223                                                        rb_node_case_insensitive);
1224                 int result = dentry_compare_names_case_insensitive(child, this);
1225
1226                 rb_parent = *new;
1227
1228                 if (result < 0)
1229                         new = &((*new)->rb_left);
1230                 else if (result > 0)
1231                         new = &((*new)->rb_right);
1232                 else
1233                         return this;
1234         }
1235         rb_link_node(&child->rb_node_case_insensitive, rb_parent, new);
1236         rb_insert_color(&child->rb_node_case_insensitive, root);
1237         return NULL;
1238 }
1239 #endif
1240
1241 /*
1242  * Links a dentry into the directory tree.
1243  *
1244  * @parent: The dentry that will be the parent of @child.
1245  * @child: The dentry to link.
1246  *
1247  * Returns NULL if successful.  If @parent already contains a dentry with the
1248  * same case-sensitive name as @child, the pointer to this duplicate dentry is
1249  * returned.
1250  */
1251 struct wim_dentry *
1252 dentry_add_child(struct wim_dentry * restrict parent,
1253                  struct wim_dentry * restrict child)
1254 {
1255         struct rb_root *root;
1256         struct rb_node **new;
1257         struct rb_node *rb_parent;
1258
1259         wimlib_assert(dentry_is_directory(parent));
1260         wimlib_assert(parent != child);
1261
1262         /* Case sensitive child dentry index */
1263         root = &parent->d_inode->i_children;
1264         new = &root->rb_node;
1265         rb_parent = NULL;
1266         while (*new) {
1267                 struct wim_dentry *this = rbnode_dentry(*new);
1268                 int result = dentry_compare_names_case_sensitive(child, this);
1269
1270                 rb_parent = *new;
1271
1272                 if (result < 0)
1273                         new = &((*new)->rb_left);
1274                 else if (result > 0)
1275                         new = &((*new)->rb_right);
1276                 else
1277                         return this;
1278         }
1279         child->parent = parent;
1280         rb_link_node(&child->rb_node, rb_parent, new);
1281         rb_insert_color(&child->rb_node, root);
1282
1283 #ifdef __WIN32__
1284         {
1285                 struct wim_dentry *existing;
1286                 existing = dentry_add_child_case_insensitive(parent, child);
1287                 if (existing) {
1288                         list_add(&child->case_insensitive_conflict_list,
1289                                  &existing->case_insensitive_conflict_list);
1290                         child->rb_node_case_insensitive.__rb_parent_color = 0;
1291                 } else {
1292                         INIT_LIST_HEAD(&child->case_insensitive_conflict_list);
1293                 }
1294         }
1295 #endif
1296         return NULL;
1297 }
1298
1299 /* Unlink a WIM dentry from the directory entry tree. */
1300 void
1301 unlink_dentry(struct wim_dentry *dentry)
1302 {
1303         struct wim_dentry *parent = dentry->parent;
1304
1305         if (parent == dentry)
1306                 return;
1307         rb_erase(&dentry->rb_node, &parent->d_inode->i_children);
1308 #ifdef __WIN32__
1309         if (dentry->rb_node_case_insensitive.__rb_parent_color) {
1310                 /* This dentry was in the case-insensitive red-black tree. */
1311                 rb_erase(&dentry->rb_node_case_insensitive,
1312                          &parent->d_inode->i_children_case_insensitive);
1313                 if (!list_empty(&dentry->case_insensitive_conflict_list)) {
1314                         /* Make a different case-insensitively-the-same dentry
1315                          * be the "representative" in the red-black tree. */
1316                         struct list_head *next;
1317                         struct wim_dentry *other;
1318                         struct wim_dentry *existing;
1319
1320                         next = dentry->case_insensitive_conflict_list.next;
1321                         other = list_entry(next, struct wim_dentry, case_insensitive_conflict_list);
1322                         existing = dentry_add_child_case_insensitive(parent, other);
1323                         wimlib_assert(existing == NULL);
1324                 }
1325         }
1326         list_del(&dentry->case_insensitive_conflict_list);
1327 #endif
1328 }
1329
1330 /*
1331  * Returns the alternate data stream entry belonging to @inode that has the
1332  * stream name @stream_name.
1333  */
1334 struct wim_ads_entry *
1335 inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name,
1336                     u16 *idx_ret)
1337 {
1338         if (inode->i_num_ads == 0) {
1339                 return NULL;
1340         } else {
1341                 size_t stream_name_utf16le_nbytes;
1342                 u16 i;
1343                 struct wim_ads_entry *result;
1344
1345         #if TCHAR_IS_UTF16LE
1346                 const utf16lechar *stream_name_utf16le;
1347
1348                 stream_name_utf16le = stream_name;
1349                 stream_name_utf16le_nbytes = tstrlen(stream_name) * sizeof(tchar);
1350         #else
1351                 utf16lechar *stream_name_utf16le;
1352
1353                 {
1354                         int ret = tstr_to_utf16le(stream_name,
1355                                                   tstrlen(stream_name) *
1356                                                       sizeof(tchar),
1357                                                   &stream_name_utf16le,
1358                                                   &stream_name_utf16le_nbytes);
1359                         if (ret)
1360                                 return NULL;
1361                 }
1362         #endif
1363                 i = 0;
1364                 result = NULL;
1365                 do {
1366                         if (ads_entry_has_name(&inode->i_ads_entries[i],
1367                                                stream_name_utf16le,
1368                                                stream_name_utf16le_nbytes))
1369                         {
1370                                 if (idx_ret)
1371                                         *idx_ret = i;
1372                                 result = &inode->i_ads_entries[i];
1373                                 break;
1374                         }
1375                 } while (++i != inode->i_num_ads);
1376         #if !TCHAR_IS_UTF16LE
1377                 FREE(stream_name_utf16le);
1378         #endif
1379                 return result;
1380         }
1381 }
1382
1383 static struct wim_ads_entry *
1384 do_inode_add_ads(struct wim_inode *inode, const void *stream_name,
1385                  size_t stream_name_nbytes, bool is_utf16le)
1386 {
1387         u16 num_ads;
1388         struct wim_ads_entry *ads_entries;
1389         struct wim_ads_entry *new_entry;
1390
1391         if (inode->i_num_ads >= 0xfffe) {
1392                 ERROR("Too many alternate data streams in one inode!");
1393                 return NULL;
1394         }
1395         num_ads = inode->i_num_ads + 1;
1396         ads_entries = REALLOC(inode->i_ads_entries,
1397                               num_ads * sizeof(inode->i_ads_entries[0]));
1398         if (!ads_entries) {
1399                 ERROR("Failed to allocate memory for new alternate data stream");
1400                 return NULL;
1401         }
1402         inode->i_ads_entries = ads_entries;
1403
1404         new_entry = &inode->i_ads_entries[num_ads - 1];
1405         if (init_ads_entry(new_entry, stream_name, stream_name_nbytes, is_utf16le))
1406                 return NULL;
1407         new_entry->stream_id = inode->i_next_stream_id++;
1408         inode->i_num_ads = num_ads;
1409         return new_entry;
1410 }
1411
1412 struct wim_ads_entry *
1413 inode_add_ads_utf16le(struct wim_inode *inode,
1414                       const utf16lechar *stream_name,
1415                       size_t stream_name_nbytes)
1416 {
1417         DEBUG("Add alternate data stream \"%"WS"\"", stream_name);
1418         return do_inode_add_ads(inode, stream_name, stream_name_nbytes, true);
1419 }
1420
1421 /*
1422  * Add an alternate stream entry to a WIM inode and return a pointer to it, or
1423  * NULL if memory could not be allocated.
1424  */
1425 struct wim_ads_entry *
1426 inode_add_ads(struct wim_inode *inode, const tchar *stream_name)
1427 {
1428         DEBUG("Add alternate data stream \"%"TS"\"", stream_name);
1429         return do_inode_add_ads(inode, stream_name,
1430                                 tstrlen(stream_name) * sizeof(tchar),
1431                                 TCHAR_IS_UTF16LE);
1432 }
1433
1434 static struct wim_lookup_table_entry *
1435 add_stream_from_data_buffer(const void *buffer, size_t size,
1436                             struct wim_lookup_table *lookup_table)
1437 {
1438         u8 hash[SHA1_HASH_SIZE];
1439         struct wim_lookup_table_entry *lte, *existing_lte;
1440
1441         sha1_buffer(buffer, size, hash);
1442         existing_lte = __lookup_resource(lookup_table, hash);
1443         if (existing_lte) {
1444                 wimlib_assert(wim_resource_size(existing_lte) == size);
1445                 lte = existing_lte;
1446                 lte->refcnt++;
1447         } else {
1448                 void *buffer_copy;
1449                 lte = new_lookup_table_entry();
1450                 if (!lte)
1451                         return NULL;
1452                 buffer_copy = memdup(buffer, size);
1453                 if (!buffer_copy) {
1454                         free_lookup_table_entry(lte);
1455                         return NULL;
1456                 }
1457                 lte->resource_location            = RESOURCE_IN_ATTACHED_BUFFER;
1458                 lte->attached_buffer              = buffer_copy;
1459                 lte->resource_entry.original_size = size;
1460                 copy_hash(lte->hash, hash);
1461                 lookup_table_insert(lookup_table, lte);
1462         }
1463         return lte;
1464 }
1465
1466 int
1467 inode_add_ads_with_data(struct wim_inode *inode, const tchar *name,
1468                         const void *value, size_t size,
1469                         struct wim_lookup_table *lookup_table)
1470 {
1471         struct wim_ads_entry *new_ads_entry;
1472
1473         wimlib_assert(inode->i_resolved);
1474
1475         new_ads_entry = inode_add_ads(inode, name);
1476         if (!new_ads_entry)
1477                 return WIMLIB_ERR_NOMEM;
1478
1479         new_ads_entry->lte = add_stream_from_data_buffer(value, size,
1480                                                          lookup_table);
1481         if (!new_ads_entry->lte) {
1482                 inode_remove_ads(inode, new_ads_entry - inode->i_ads_entries,
1483                                  lookup_table);
1484                 return WIMLIB_ERR_NOMEM;
1485         }
1486         return 0;
1487 }
1488
1489 /* Set the unnamed stream of a WIM inode, given a data buffer containing the
1490  * stream contents. */
1491 int
1492 inode_set_unnamed_stream(struct wim_inode *inode, const void *data, size_t len,
1493                          struct wim_lookup_table *lookup_table)
1494 {
1495         inode->i_lte = add_stream_from_data_buffer(data, len, lookup_table);
1496         if (!inode->i_lte)
1497                 return WIMLIB_ERR_NOMEM;
1498         inode->i_resolved = 1;
1499         return 0;
1500 }
1501
1502 /* Remove an alternate data stream from a WIM inode  */
1503 void
1504 inode_remove_ads(struct wim_inode *inode, u16 idx,
1505                  struct wim_lookup_table *lookup_table)
1506 {
1507         struct wim_ads_entry *ads_entry;
1508         struct wim_lookup_table_entry *lte;
1509
1510         wimlib_assert(idx < inode->i_num_ads);
1511         wimlib_assert(inode->i_resolved);
1512
1513         ads_entry = &inode->i_ads_entries[idx];
1514
1515         DEBUG("Remove alternate data stream \"%"WS"\"", ads_entry->stream_name);
1516
1517         lte = ads_entry->lte;
1518         if (lte)
1519                 lte_decrement_refcnt(lte, lookup_table);
1520
1521         destroy_ads_entry(ads_entry);
1522
1523         memmove(&inode->i_ads_entries[idx],
1524                 &inode->i_ads_entries[idx + 1],
1525                 (inode->i_num_ads - idx - 1) * sizeof(inode->i_ads_entries[0]));
1526         inode->i_num_ads--;
1527 }
1528
1529 #ifndef __WIN32__
1530 int
1531 inode_get_unix_data(const struct wim_inode *inode,
1532                     struct wimlib_unix_data *unix_data,
1533                     u16 *stream_idx_ret)
1534 {
1535         const struct wim_ads_entry *ads_entry;
1536         const struct wim_lookup_table_entry *lte;
1537         size_t size;
1538         int ret;
1539
1540         wimlib_assert(inode->i_resolved);
1541
1542         ads_entry = inode_get_ads_entry((struct wim_inode*)inode,
1543                                         WIMLIB_UNIX_DATA_TAG, NULL);
1544         if (!ads_entry)
1545                 return NO_UNIX_DATA;
1546
1547         if (stream_idx_ret)
1548                 *stream_idx_ret = ads_entry - inode->i_ads_entries;
1549
1550         lte = ads_entry->lte;
1551         if (!lte)
1552                 return NO_UNIX_DATA;
1553
1554         size = wim_resource_size(lte);
1555         if (size != sizeof(struct wimlib_unix_data))
1556                 return BAD_UNIX_DATA;
1557
1558         ret = read_full_resource_into_buf(lte, unix_data);
1559         if (ret)
1560                 return ret;
1561
1562         if (unix_data->version != 0)
1563                 return BAD_UNIX_DATA;
1564         return 0;
1565 }
1566
1567 int
1568 inode_set_unix_data(struct wim_inode *inode, uid_t uid, gid_t gid, mode_t mode,
1569                     struct wim_lookup_table *lookup_table, int which)
1570 {
1571         struct wimlib_unix_data unix_data;
1572         int ret;
1573         bool have_good_unix_data = false;
1574         bool have_unix_data = false;
1575         u16 stream_idx;
1576
1577         if (!(which & UNIX_DATA_CREATE)) {
1578                 ret = inode_get_unix_data(inode, &unix_data, &stream_idx);
1579                 if (ret == 0 || ret == BAD_UNIX_DATA || ret > 0)
1580                         have_unix_data = true;
1581                 if (ret == 0)
1582                         have_good_unix_data = true;
1583         }
1584         unix_data.version = 0;
1585         if (which & UNIX_DATA_UID || !have_good_unix_data)
1586                 unix_data.uid = uid;
1587         if (which & UNIX_DATA_GID || !have_good_unix_data)
1588                 unix_data.gid = gid;
1589         if (which & UNIX_DATA_MODE || !have_good_unix_data)
1590                 unix_data.mode = mode;
1591         ret = inode_add_ads_with_data(inode, WIMLIB_UNIX_DATA_TAG,
1592                                       &unix_data,
1593                                       sizeof(struct wimlib_unix_data),
1594                                       lookup_table);
1595         if (ret == 0 && have_unix_data)
1596                 inode_remove_ads(inode, stream_idx, lookup_table);
1597         return ret;
1598 }
1599 #endif /* !__WIN32__ */
1600
1601 /*
1602  * Reads the alternate data stream entries of a WIM dentry.
1603  *
1604  * @p:  Pointer to buffer that starts with the first alternate stream entry.
1605  *
1606  * @inode:      Inode to load the alternate data streams into.
1607  *              @inode->i_num_ads must have been set to the number of
1608  *              alternate data streams that are expected.
1609  *
1610  * @remaining_size:     Number of bytes of data remaining in the buffer pointed
1611  *                      to by @p.
1612  *
1613  *
1614  * Return 0 on success or nonzero on failure.  On success, inode->i_ads_entries
1615  * is set to an array of `struct wim_ads_entry's of length inode->i_num_ads.  On
1616  * failure, @inode is not modified.
1617  */
1618 static int
1619 read_ads_entries(const u8 * restrict p, struct wim_inode * restrict inode,
1620                  size_t nbytes_remaining)
1621 {
1622         u16 num_ads;
1623         struct wim_ads_entry *ads_entries;
1624         int ret;
1625
1626         BUILD_BUG_ON(sizeof(struct wim_ads_entry_on_disk) != WIM_ADS_ENTRY_DISK_SIZE);
1627
1628         /* Allocate an array for our in-memory representation of the alternate
1629          * data stream entries. */
1630         num_ads = inode->i_num_ads;
1631         ads_entries = CALLOC(num_ads, sizeof(inode->i_ads_entries[0]));
1632         if (!ads_entries)
1633                 goto out_of_memory;
1634
1635         /* Read the entries into our newly allocated buffer. */
1636         for (u16 i = 0; i < num_ads; i++) {
1637                 u64 length;
1638                 struct wim_ads_entry *cur_entry;
1639                 const struct wim_ads_entry_on_disk *disk_entry =
1640                         (const struct wim_ads_entry_on_disk*)p;
1641
1642                 cur_entry = &ads_entries[i];
1643                 ads_entries[i].stream_id = i + 1;
1644
1645                 /* Do we have at least the size of the fixed-length data we know
1646                  * need? */
1647                 if (nbytes_remaining < sizeof(struct wim_ads_entry_on_disk))
1648                         goto out_invalid;
1649
1650                 /* Read the length field */
1651                 length = le64_to_cpu(disk_entry->length);
1652
1653                 /* Make sure the length field is neither so small it doesn't
1654                  * include all the fixed-length data nor so large it overflows
1655                  * the metadata resource buffer. */
1656                 if (length < sizeof(struct wim_ads_entry_on_disk) ||
1657                     length > nbytes_remaining)
1658                         goto out_invalid;
1659
1660                 /* Read the rest of the fixed-length data. */
1661
1662                 cur_entry->reserved = le64_to_cpu(disk_entry->reserved);
1663                 copy_hash(cur_entry->hash, disk_entry->hash);
1664                 cur_entry->stream_name_nbytes = le16_to_cpu(disk_entry->stream_name_nbytes);
1665
1666                 /* If stream_name_nbytes != 0, this is a named stream.
1667                  * Otherwise this is an unnamed stream, or in some cases (bugs
1668                  * in Microsoft's software I guess) a meaningless entry
1669                  * distinguished from the real unnamed stream entry, if any, by
1670                  * the fact that the real unnamed stream entry has a nonzero
1671                  * hash field. */
1672                 if (cur_entry->stream_name_nbytes) {
1673                         /* The name is encoded in UTF16-LE, which uses 2-byte
1674                          * coding units, so the length of the name had better be
1675                          * an even number of bytes... */
1676                         if (cur_entry->stream_name_nbytes & 1)
1677                                 goto out_invalid;
1678
1679                         /* Add the length of the stream name to get the length
1680                          * we actually need to read.  Make sure this isn't more
1681                          * than the specified length of the entry. */
1682                         if (sizeof(struct wim_ads_entry_on_disk) +
1683                             cur_entry->stream_name_nbytes > length)
1684                                 goto out_invalid;
1685
1686                         cur_entry->stream_name = MALLOC(cur_entry->stream_name_nbytes + 2);
1687                         if (!cur_entry->stream_name)
1688                                 goto out_of_memory;
1689
1690                         memcpy(cur_entry->stream_name,
1691                                disk_entry->stream_name,
1692                                cur_entry->stream_name_nbytes);
1693                         cur_entry->stream_name[cur_entry->stream_name_nbytes / 2] = cpu_to_le16(0);
1694                 }
1695
1696                 /* It's expected that the size of every ADS entry is a multiple
1697                  * of 8.  However, to be safe, I'm allowing the possibility of
1698                  * an ADS entry at the very end of the metadata resource ending
1699                  * un-aligned.  So although we still need to increment the input
1700                  * pointer by @length to reach the next ADS entry, it's possible
1701                  * that less than @length is actually remaining in the metadata
1702                  * resource. We should set the remaining bytes to 0 if this
1703                  * happens. */
1704                 length = (length + 7) & ~(u64)7;
1705                 p += length;
1706                 if (nbytes_remaining < length)
1707                         nbytes_remaining = 0;
1708                 else
1709                         nbytes_remaining -= length;
1710         }
1711         inode->i_ads_entries = ads_entries;
1712         inode->i_next_stream_id = inode->i_num_ads + 1;
1713         ret = 0;
1714         goto out;
1715 out_of_memory:
1716         ret = WIMLIB_ERR_NOMEM;
1717         goto out_free_ads_entries;
1718 out_invalid:
1719         ERROR("An alternate data stream entry is invalid");
1720         ret = WIMLIB_ERR_INVALID_DENTRY;
1721 out_free_ads_entries:
1722         if (ads_entries) {
1723                 for (u16 i = 0; i < num_ads; i++)
1724                         destroy_ads_entry(&ads_entries[i]);
1725                 FREE(ads_entries);
1726         }
1727 out:
1728         return ret;
1729 }
1730
1731 /*
1732  * Reads a WIM directory entry, including all alternate data stream entries that
1733  * follow it, from the WIM image's metadata resource.
1734  *
1735  * @metadata_resource:
1736  *              Pointer to the metadata resource buffer.
1737  *
1738  * @metadata_resource_len:
1739  *              Length of the metadata resource buffer, in bytes.
1740  *
1741  * @offset:     Offset of the dentry within the metadata resource.
1742  *
1743  * @dentry:     A `struct wim_dentry' that will be filled in by this function.
1744  *
1745  * Return 0 on success or nonzero on failure.  On failure, @dentry will have
1746  * been modified, but it will not be left with pointers to any allocated
1747  * buffers.  On success, the dentry->length field must be examined.  If zero,
1748  * this was a special "end of directory" dentry and not a real dentry.  If
1749  * nonzero, this was a real dentry.
1750  *
1751  * Possible errors include:
1752  *      WIMLIB_ERR_NOMEM
1753  *      WIMLIB_ERR_INVALID_DENTRY
1754  */
1755 int
1756 read_dentry(const u8 * restrict metadata_resource, u64 metadata_resource_len,
1757             u64 offset, struct wim_dentry * restrict dentry)
1758 {
1759
1760         u64 calculated_size;
1761         utf16lechar *file_name;
1762         utf16lechar *short_name;
1763         u16 short_name_nbytes;
1764         u16 file_name_nbytes;
1765         int ret;
1766         struct wim_inode *inode;
1767         const u8 *p = &metadata_resource[offset];
1768         const struct wim_dentry_on_disk *disk_dentry =
1769                         (const struct wim_dentry_on_disk*)p;
1770
1771         BUILD_BUG_ON(sizeof(struct wim_dentry_on_disk) != WIM_DENTRY_DISK_SIZE);
1772
1773         if ((uintptr_t)p & 7)
1774                 WARNING("WIM dentry is not 8-byte aligned");
1775
1776         dentry_common_init(dentry);
1777
1778         /* Before reading the whole dentry, we need to read just the length.
1779          * This is because a dentry of length 8 (that is, just the length field)
1780          * terminates the list of sibling directory entries. */
1781         if (offset + sizeof(u64) > metadata_resource_len ||
1782             offset + sizeof(u64) < offset)
1783         {
1784                 ERROR("Directory entry starting at %"PRIu64" ends past the "
1785                       "end of the metadata resource (size %"PRIu64")",
1786                       offset, metadata_resource_len);
1787                 return WIMLIB_ERR_INVALID_DENTRY;
1788         }
1789         dentry->length = le64_to_cpu(disk_dentry->length);
1790
1791         /* A zero length field (really a length of 8, since that's how big the
1792          * directory entry is...) indicates that this is the end of directory
1793          * dentry.  We do not read it into memory as an actual dentry, so just
1794          * return successfully in this case. */
1795         if (dentry->length == 8)
1796                 dentry->length = 0;
1797         if (dentry->length == 0)
1798                 return 0;
1799
1800         /* Now that we have the actual length provided in the on-disk structure,
1801          * again make sure it doesn't overflow the metadata resource buffer. */
1802         if (offset + dentry->length > metadata_resource_len ||
1803             offset + dentry->length < offset)
1804         {
1805                 ERROR("Directory entry at offset %"PRIu64" and with size "
1806                       "%"PRIu64" ends past the end of the metadata resource "
1807                       "(size %"PRIu64")",
1808                       offset, dentry->length, metadata_resource_len);
1809                 return WIMLIB_ERR_INVALID_DENTRY;
1810         }
1811
1812         /* Make sure the dentry length is at least as large as the number of
1813          * fixed-length fields */
1814         if (dentry->length < sizeof(struct wim_dentry_on_disk)) {
1815                 ERROR("Directory entry has invalid length of %"PRIu64" bytes",
1816                       dentry->length);
1817                 return WIMLIB_ERR_INVALID_DENTRY;
1818         }
1819
1820         /* Allocate a `struct wim_inode' for this `struct wim_dentry'. */
1821         inode = new_timeless_inode();
1822         if (!inode)
1823                 return WIMLIB_ERR_NOMEM;
1824
1825         /* Read more fields; some into the dentry, and some into the inode. */
1826
1827         inode->i_attributes = le32_to_cpu(disk_dentry->attributes);
1828         inode->i_security_id = le32_to_cpu(disk_dentry->security_id);
1829         dentry->subdir_offset = le64_to_cpu(disk_dentry->subdir_offset);
1830         dentry->d_unused_1 = le64_to_cpu(disk_dentry->unused_1);
1831         dentry->d_unused_2 = le64_to_cpu(disk_dentry->unused_2);
1832         inode->i_creation_time = le64_to_cpu(disk_dentry->creation_time);
1833         inode->i_last_access_time = le64_to_cpu(disk_dentry->last_access_time);
1834         inode->i_last_write_time = le64_to_cpu(disk_dentry->last_write_time);
1835         copy_hash(inode->i_hash, disk_dentry->unnamed_stream_hash);
1836
1837         /* I don't know what's going on here.  It seems like M$ screwed up the
1838          * reparse points, then put the fields in the same place and didn't
1839          * document it.  So we have some fields we read for reparse points, and
1840          * some fields in the same place for non-reparse-point.s */
1841         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1842                 inode->i_rp_unknown_1 = le32_to_cpu(disk_dentry->reparse.rp_unknown_1);
1843                 inode->i_reparse_tag = le32_to_cpu(disk_dentry->reparse.reparse_tag);
1844                 inode->i_rp_unknown_2 = le16_to_cpu(disk_dentry->reparse.rp_unknown_2);
1845                 inode->i_not_rpfixed = le16_to_cpu(disk_dentry->reparse.not_rpfixed);
1846                 /* Leave inode->i_ino at 0.  Note that this means the WIM file
1847                  * cannot archive hard-linked reparse points.  Such a thing
1848                  * doesn't really make sense anyway, although I believe it's
1849                  * theoretically possible to have them on NTFS. */
1850         } else {
1851                 inode->i_rp_unknown_1 = le32_to_cpu(disk_dentry->nonreparse.rp_unknown_1);
1852                 inode->i_ino = le64_to_cpu(disk_dentry->nonreparse.hard_link_group_id);
1853         }
1854
1855         inode->i_num_ads = le16_to_cpu(disk_dentry->num_alternate_data_streams);
1856
1857         short_name_nbytes = le16_to_cpu(disk_dentry->short_name_nbytes);
1858         file_name_nbytes = le16_to_cpu(disk_dentry->file_name_nbytes);
1859
1860         if ((short_name_nbytes & 1) | (file_name_nbytes & 1))
1861         {
1862                 ERROR("Dentry name is not valid UTF-16LE (odd number of bytes)!");
1863                 ret = WIMLIB_ERR_INVALID_DENTRY;
1864                 goto out_free_inode;
1865         }
1866
1867         /* We now know the length of the file name and short name.  Make sure
1868          * the length of the dentry is large enough to actually hold them.
1869          *
1870          * The calculated length here is unaligned to allow for the possibility
1871          * that the dentry->length names an unaligned length, although this
1872          * would be unexpected. */
1873         calculated_size = _dentry_correct_length_unaligned(file_name_nbytes,
1874                                                            short_name_nbytes);
1875
1876         if (dentry->length < calculated_size) {
1877                 ERROR("Unexpected end of directory entry! (Expected "
1878                       "at least %"PRIu64" bytes, got %"PRIu64" bytes.)",
1879                       calculated_size, dentry->length);
1880                 ret = WIMLIB_ERR_INVALID_DENTRY;
1881                 goto out_free_inode;
1882         }
1883
1884         p += sizeof(struct wim_dentry_on_disk);
1885
1886         /* Read the filename if present.  Note: if the filename is empty, there
1887          * is no null terminator following it. */
1888         if (file_name_nbytes) {
1889                 file_name = MALLOC(file_name_nbytes + 2);
1890                 if (!file_name) {
1891                         ERROR("Failed to allocate %d bytes for dentry file name",
1892                               file_name_nbytes + 2);
1893                         ret = WIMLIB_ERR_NOMEM;
1894                         goto out_free_inode;
1895                 }
1896                 memcpy(file_name, p, file_name_nbytes);
1897                 p += file_name_nbytes + 2;
1898                 file_name[file_name_nbytes / 2] = cpu_to_le16(0);
1899         } else {
1900                 file_name = NULL;
1901         }
1902
1903
1904         /* Read the short filename if present.  Note: if there is no short
1905          * filename, there is no null terminator following it. */
1906         if (short_name_nbytes) {
1907                 short_name = MALLOC(short_name_nbytes + 2);
1908                 if (!short_name) {
1909                         ERROR("Failed to allocate %d bytes for dentry short name",
1910                               short_name_nbytes + 2);
1911                         ret = WIMLIB_ERR_NOMEM;
1912                         goto out_free_file_name;
1913                 }
1914                 memcpy(short_name, p, short_name_nbytes);
1915                 p += short_name_nbytes + 2;
1916                 short_name[short_name_nbytes / 2] = cpu_to_le16(0);
1917         } else {
1918                 short_name = NULL;
1919         }
1920
1921         /* Align the dentry length */
1922         dentry->length = (dentry->length + 7) & ~7;
1923
1924         /*
1925          * Read the alternate data streams, if present.  dentry->num_ads tells
1926          * us how many they are, and they will directly follow the dentry
1927          * on-disk.
1928          *
1929          * Note that each alternate data stream entry begins on an 8-byte
1930          * aligned boundary, and the alternate data stream entries seem to NOT
1931          * be included in the dentry->length field for some reason.
1932          */
1933         if (inode->i_num_ads != 0) {
1934                 ret = WIMLIB_ERR_INVALID_DENTRY;
1935                 if (offset + dentry->length > metadata_resource_len ||
1936                     (ret = read_ads_entries(&metadata_resource[offset + dentry->length],
1937                                             inode,
1938                                             metadata_resource_len - offset - dentry->length)))
1939                 {
1940                         ERROR("Failed to read alternate data stream "
1941                               "entries of WIM dentry \"%"WS"\"", file_name);
1942                         goto out_free_short_name;
1943                 }
1944         }
1945         /* We've read all the data for this dentry.  Set the names and their
1946          * lengths, and we've done. */
1947         dentry->d_inode           = inode;
1948         dentry->file_name         = file_name;
1949         dentry->short_name        = short_name;
1950         dentry->file_name_nbytes  = file_name_nbytes;
1951         dentry->short_name_nbytes = short_name_nbytes;
1952         ret = 0;
1953         goto out;
1954 out_free_short_name:
1955         FREE(short_name);
1956 out_free_file_name:
1957         FREE(file_name);
1958 out_free_inode:
1959         free_inode(inode);
1960 out:
1961         return ret;
1962 }
1963
1964 static const tchar *
1965 dentry_get_file_type_string(const struct wim_dentry *dentry)
1966 {
1967         const struct wim_inode *inode = dentry->d_inode;
1968         if (inode_is_directory(inode))
1969                 return T("directory");
1970         else if (inode_is_symlink(inode))
1971                 return T("symbolic link");
1972         else
1973                 return T("file");
1974 }
1975
1976 /* Reads the children of a dentry, and all their children, ..., etc. from the
1977  * metadata resource and into the dentry tree.
1978  *
1979  * @metadata_resource:  An array that contains the uncompressed metadata
1980  *                      resource for the WIM file.
1981  *
1982  * @metadata_resource_len:  The length of the uncompressed metadata resource, in
1983  *                          bytes.
1984  *
1985  * @dentry:     A pointer to a `struct wim_dentry' that is the root of the directory
1986  *              tree and has already been read from the metadata resource.  It
1987  *              does not need to be the real root because this procedure is
1988  *              called recursively.
1989  *
1990  * Returns zero on success; nonzero on failure.
1991  */
1992 int
1993 read_dentry_tree(const u8 * restrict metadata_resource,
1994                  u64 metadata_resource_len,
1995                  struct wim_dentry * restrict dentry)
1996 {
1997         u64 cur_offset = dentry->subdir_offset;
1998         struct wim_dentry *child;
1999         struct wim_dentry *duplicate;
2000         struct wim_dentry *parent;
2001         struct wim_dentry cur_child;
2002         int ret;
2003
2004         /*
2005          * If @dentry has no child dentries, nothing more needs to be done for
2006          * this branch.  This is the case for regular files, symbolic links, and
2007          * *possibly* empty directories (although an empty directory may also
2008          * have one child dentry that is the special end-of-directory dentry)
2009          */
2010         if (cur_offset == 0)
2011                 return 0;
2012
2013         /* Check for cyclic directory structure */
2014         for (parent = dentry->parent; !dentry_is_root(parent); parent = parent->parent)
2015         {
2016                 if (unlikely(parent->subdir_offset == cur_offset)) {
2017                         ERROR("Cyclic directory structure directed: children "
2018                               "of \"%"TS"\" coincide with children of \"%"TS"\"",
2019                               dentry_full_path(dentry),
2020                               dentry_full_path(parent));
2021                         return WIMLIB_ERR_INVALID_DENTRY;
2022                 }
2023         }
2024
2025         /* Find and read all the children of @dentry. */
2026         for (;;) {
2027
2028                 /* Read next child of @dentry into @cur_child. */
2029                 ret = read_dentry(metadata_resource, metadata_resource_len,
2030                                   cur_offset, &cur_child);
2031                 if (ret)
2032                         break;
2033
2034                 /* Check for end of directory. */
2035                 if (cur_child.length == 0)
2036                         break;
2037
2038                 /* Not end of directory.  Allocate this child permanently and
2039                  * link it to the parent and previous child. */
2040                 child = memdup(&cur_child, sizeof(struct wim_dentry));
2041                 if (!child) {
2042                         ERROR("Failed to allocate new dentry!");
2043                         ret = WIMLIB_ERR_NOMEM;
2044                         break;
2045                 }
2046
2047                 /* Advance to the offset of the next child.  Note: We need to
2048                  * advance by the TOTAL length of the dentry, not by the length
2049                  * cur_child.length, which although it does take into account
2050                  * the padding, it DOES NOT take into account alternate stream
2051                  * entries. */
2052                 cur_offset += dentry_total_length(child);
2053
2054                 if (unlikely(!dentry_has_long_name(child))) {
2055                         WARNING("Ignoring unnamed dentry in "
2056                                 "directory \"%"TS"\"",
2057                                 dentry_full_path(dentry));
2058                         free_dentry(child);
2059                         continue;
2060                 }
2061
2062                 duplicate = dentry_add_child(dentry, child);
2063                 if (unlikely(duplicate)) {
2064                         const tchar *child_type, *duplicate_type;
2065                         child_type = dentry_get_file_type_string(child);
2066                         duplicate_type = dentry_get_file_type_string(duplicate);
2067                         WARNING("Ignoring duplicate %"TS" \"%"TS"\" "
2068                                 "(the WIM image already contains a %"TS" "
2069                                 "at that path with the exact same name)",
2070                                 child_type, dentry_full_path(duplicate),
2071                                 duplicate_type);
2072                         free_dentry(child);
2073                         continue;
2074                 }
2075
2076                 inode_add_dentry(child, child->d_inode);
2077                 /* If there are children of this child, call this
2078                  * procedure recursively. */
2079                 if (child->subdir_offset != 0) {
2080                         if (likely(dentry_is_directory(child))) {
2081                                 ret = read_dentry_tree(metadata_resource,
2082                                                        metadata_resource_len,
2083                                                        child);
2084                                 if (ret)
2085                                         break;
2086                         } else {
2087                                 WARNING("Ignoring children of non-directory \"%"TS"\"",
2088                                         dentry_full_path(child));
2089                         }
2090                 }
2091         }
2092         return ret;
2093 }
2094
2095 /*
2096  * Writes a WIM dentry to an output buffer.
2097  *
2098  * @dentry:  The dentry structure.
2099  * @p:       The memory location to write the data to.
2100  *
2101  * Returns the pointer to the byte after the last byte we wrote as part of the
2102  * dentry, including any alternate data stream entries.
2103  */
2104 static u8 *
2105 write_dentry(const struct wim_dentry * restrict dentry, u8 * restrict p)
2106 {
2107         const struct wim_inode *inode;
2108         struct wim_dentry_on_disk *disk_dentry;
2109         const u8 *orig_p;
2110         const u8 *hash;
2111
2112         wimlib_assert(((uintptr_t)p & 7) == 0); /* 8 byte aligned */
2113         orig_p = p;
2114
2115         inode = dentry->d_inode;
2116         disk_dentry = (struct wim_dentry_on_disk*)p;
2117
2118         disk_dentry->attributes = cpu_to_le32(inode->i_attributes);
2119         disk_dentry->security_id = cpu_to_le32(inode->i_security_id);
2120         disk_dentry->subdir_offset = cpu_to_le64(dentry->subdir_offset);
2121         disk_dentry->unused_1 = cpu_to_le64(dentry->d_unused_1);
2122         disk_dentry->unused_2 = cpu_to_le64(dentry->d_unused_2);
2123         disk_dentry->creation_time = cpu_to_le64(inode->i_creation_time);
2124         disk_dentry->last_access_time = cpu_to_le64(inode->i_last_access_time);
2125         disk_dentry->last_write_time = cpu_to_le64(inode->i_last_write_time);
2126         hash = inode_stream_hash(inode, 0);
2127         copy_hash(disk_dentry->unnamed_stream_hash, hash);
2128         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
2129                 disk_dentry->reparse.rp_unknown_1 = cpu_to_le32(inode->i_rp_unknown_1);
2130                 disk_dentry->reparse.reparse_tag = cpu_to_le32(inode->i_reparse_tag);
2131                 disk_dentry->reparse.rp_unknown_2 = cpu_to_le16(inode->i_rp_unknown_2);
2132                 disk_dentry->reparse.not_rpfixed = cpu_to_le16(inode->i_not_rpfixed);
2133         } else {
2134                 disk_dentry->nonreparse.rp_unknown_1 = cpu_to_le32(inode->i_rp_unknown_1);
2135                 disk_dentry->nonreparse.hard_link_group_id =
2136                         cpu_to_le64((inode->i_nlink == 1) ? 0 : inode->i_ino);
2137         }
2138         disk_dentry->num_alternate_data_streams = cpu_to_le16(inode->i_num_ads);
2139         disk_dentry->short_name_nbytes = cpu_to_le16(dentry->short_name_nbytes);
2140         disk_dentry->file_name_nbytes = cpu_to_le16(dentry->file_name_nbytes);
2141         p += sizeof(struct wim_dentry_on_disk);
2142
2143         wimlib_assert(dentry_is_root(dentry) != dentry_has_long_name(dentry));
2144
2145         if (dentry_has_long_name(dentry))
2146                 p = mempcpy(p, dentry->file_name, dentry->file_name_nbytes + 2);
2147
2148         if (dentry_has_short_name(dentry))
2149                 p = mempcpy(p, dentry->short_name, dentry->short_name_nbytes + 2);
2150
2151         /* Align to 8-byte boundary */
2152         while ((uintptr_t)p & 7)
2153                 *p++ = 0;
2154
2155         /* We calculate the correct length of the dentry ourselves because the
2156          * dentry->length field may been set to an unexpected value from when we
2157          * read the dentry in (for example, there may have been unknown data
2158          * appended to the end of the dentry...).  Furthermore, the dentry may
2159          * have been renamed, thus changing its needed length. */
2160         disk_dentry->length = cpu_to_le64(p - orig_p);
2161
2162         /* Write the alternate data streams entries, if any. */
2163         for (u16 i = 0; i < inode->i_num_ads; i++) {
2164                 const struct wim_ads_entry *ads_entry =
2165                                 &inode->i_ads_entries[i];
2166                 struct wim_ads_entry_on_disk *disk_ads_entry =
2167                                 (struct wim_ads_entry_on_disk*)p;
2168                 orig_p = p;
2169
2170                 disk_ads_entry->reserved = cpu_to_le64(ads_entry->reserved);
2171
2172                 hash = inode_stream_hash(inode, i + 1);
2173                 copy_hash(disk_ads_entry->hash, hash);
2174                 disk_ads_entry->stream_name_nbytes = cpu_to_le16(ads_entry->stream_name_nbytes);
2175                 p += sizeof(struct wim_ads_entry_on_disk);
2176                 if (ads_entry->stream_name_nbytes) {
2177                         p = mempcpy(p, ads_entry->stream_name,
2178                                     ads_entry->stream_name_nbytes + 2);
2179                 }
2180                 /* Align to 8-byte boundary */
2181                 while ((uintptr_t)p & 7)
2182                         *p++ = 0;
2183                 disk_ads_entry->length = cpu_to_le64(p - orig_p);
2184         }
2185         return p;
2186 }
2187
2188 static int
2189 write_dentry_cb(struct wim_dentry *dentry, void *_p)
2190 {
2191         u8 **p = _p;
2192         *p = write_dentry(dentry, *p);
2193         return 0;
2194 }
2195
2196 static u8 *
2197 write_dentry_tree_recursive(const struct wim_dentry *parent, u8 *p);
2198
2199 static int
2200 write_dentry_tree_recursive_cb(struct wim_dentry *dentry, void *_p)
2201 {
2202         u8 **p = _p;
2203         *p = write_dentry_tree_recursive(dentry, *p);
2204         return 0;
2205 }
2206
2207 /* Recursive function that writes a dentry tree rooted at @parent, not including
2208  * @parent itself, which has already been written. */
2209 static u8 *
2210 write_dentry_tree_recursive(const struct wim_dentry *parent, u8 *p)
2211 {
2212         /* Nothing to do if this dentry has no children. */
2213         if (parent->subdir_offset == 0)
2214                 return p;
2215
2216         /* Write child dentries and end-of-directory entry.
2217          *
2218          * Note: we need to write all of this dentry's children before
2219          * recursively writing the directory trees rooted at each of the child
2220          * dentries, since the on-disk dentries for a dentry's children are
2221          * always located at consecutive positions in the metadata resource! */
2222         for_dentry_child(parent, write_dentry_cb, &p);
2223
2224         /* write end of directory entry */
2225         *(le64*)p = cpu_to_le64(0);
2226         p += 8;
2227
2228         /* Recurse on children. */
2229         for_dentry_child(parent, write_dentry_tree_recursive_cb, &p);
2230         return p;
2231 }
2232
2233 /* Writes a directory tree to the metadata resource.
2234  *
2235  * @root:       Root of the dentry tree.
2236  * @p:          Pointer to a buffer with enough space for the dentry tree.
2237  *
2238  * Returns pointer to the byte after the last byte we wrote.
2239  */
2240 u8 *
2241 write_dentry_tree(const struct wim_dentry * restrict root, u8 * restrict p)
2242 {
2243         DEBUG("Writing dentry tree.");
2244         wimlib_assert(dentry_is_root(root));
2245
2246         /* If we're the root dentry, we have no parent that already
2247          * wrote us, so we need to write ourselves. */
2248         p = write_dentry(root, p);
2249
2250         /* Write end of directory entry after the root dentry just to be safe;
2251          * however the root dentry obviously cannot have any siblings. */
2252         *(le64*)p = cpu_to_le64(0);
2253         p += 8;
2254
2255         /* Recursively write the rest of the dentry tree. */
2256         return write_dentry_tree_recursive(root, p);
2257 }