f986f9df12fbfe02624b70bbc66dee964565028c
[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 /* WIM directory entry (on-disk format) */
76 struct wim_dentry_on_disk {
77         le64 length;
78         le32 attributes;
79         sle32 security_id;
80         le64 subdir_offset;
81         le64 unused_1;
82         le64 unused_2;
83         le64 creation_time;
84         le64 last_access_time;
85         le64 last_write_time;
86         u8 unnamed_stream_hash[SHA1_HASH_SIZE];
87         union {
88                 struct {
89                         le32 rp_unknown_1;
90                         le32 reparse_tag;
91                         le16 rp_unknown_2;
92                         le16 not_rpfixed;
93                 } _packed_attribute reparse;
94                 struct {
95                         le32 rp_unknown_1;
96                         le64 hard_link_group_id;
97                 } _packed_attribute nonreparse;
98         };
99         le16 num_alternate_data_streams;
100         le16 short_name_nbytes;
101         le16 file_name_nbytes;
102
103         /* Follewed by variable length file name, if file_name_nbytes != 0 */
104         utf16lechar file_name[];
105
106         /* Followed by variable length short name, if short_name_nbytes != 0 */
107         /*utf16lechar short_name[];*/
108 } _packed_attribute;
109
110 #define WIM_DENTRY_DISK_SIZE 102
111
112 /* Calculates the unaligned length, in bytes, of an on-disk WIM dentry that has
113  * a file name and short name that take the specified numbers of bytes.  This
114  * excludes any alternate data stream entries that may follow the dentry. */
115 static u64
116 _dentry_correct_length_unaligned(u16 file_name_nbytes, u16 short_name_nbytes)
117 {
118         u64 length = sizeof(struct wim_dentry_on_disk);
119         if (file_name_nbytes)
120                 length += file_name_nbytes + 2;
121         if (short_name_nbytes)
122                 length += short_name_nbytes + 2;
123         return length;
124 }
125
126 /* Calculates the unaligned length, in bytes, of an on-disk WIM dentry, based on
127  * the file name length and short name length.  Note that dentry->length is
128  * ignored; also, this excludes any alternate data stream entries that may
129  * follow the dentry. */
130 static u64
131 dentry_correct_length_unaligned(const struct wim_dentry *dentry)
132 {
133         return _dentry_correct_length_unaligned(dentry->file_name_nbytes,
134                                                 dentry->short_name_nbytes);
135 }
136
137 /* Return %true iff the alternate data stream entry @entry has the UTF-16LE
138  * stream name @name that has length @name_nbytes bytes. */
139 static inline bool
140 ads_entry_has_name(const struct wim_ads_entry *entry,
141                    const utf16lechar *name, size_t name_nbytes)
142 {
143         return entry->stream_name_nbytes == name_nbytes &&
144                memcmp(entry->stream_name, name, name_nbytes) == 0;
145 }
146
147 /* Duplicates a string of system-dependent encoding into a UTF-16LE string and
148  * returns the string and its length, in bytes, in the pointer arguments.  Frees
149  * any existing string at the return location before overwriting it. */
150 static int
151 get_utf16le_name(const tchar *name, utf16lechar **name_utf16le_ret,
152                  u16 *name_utf16le_nbytes_ret)
153 {
154         utf16lechar *name_utf16le;
155         size_t name_utf16le_nbytes;
156         int ret;
157 #if TCHAR_IS_UTF16LE
158         name_utf16le_nbytes = tstrlen(name) * sizeof(utf16lechar);
159         name_utf16le = MALLOC(name_utf16le_nbytes + sizeof(utf16lechar));
160         if (!name_utf16le)
161                 return WIMLIB_ERR_NOMEM;
162         memcpy(name_utf16le, name, name_utf16le_nbytes + sizeof(utf16lechar));
163         ret = 0;
164 #else
165
166         ret = tstr_to_utf16le(name, tstrlen(name), &name_utf16le,
167                               &name_utf16le_nbytes);
168         if (ret == 0) {
169                 if (name_utf16le_nbytes > 0xffff) {
170                         FREE(name_utf16le);
171                         ERROR("Multibyte string \"%"TS"\" is too long!", name);
172                         ret = WIMLIB_ERR_INVALID_UTF8_STRING;
173                 }
174         }
175 #endif
176         if (ret == 0) {
177                 FREE(*name_utf16le_ret);
178                 *name_utf16le_ret = name_utf16le;
179                 *name_utf16le_nbytes_ret = name_utf16le_nbytes;
180         }
181         return ret;
182 }
183
184 /* Sets the name of a WIM dentry from a multibyte string. */
185 int
186 set_dentry_name(struct wim_dentry *dentry, const tchar *new_name)
187 {
188         int ret;
189         ret = get_utf16le_name(new_name, &dentry->file_name,
190                                &dentry->file_name_nbytes);
191         if (ret == 0) {
192                 /* Clear the short name and recalculate the dentry length */
193                 if (dentry_has_short_name(dentry)) {
194                         FREE(dentry->short_name);
195                         dentry->short_name = NULL;
196                         dentry->short_name_nbytes = 0;
197                 }
198         }
199         return ret;
200 }
201
202 /* Returns the total length of a WIM alternate data stream entry on-disk,
203  * including the stream name, the null terminator, AND the padding after the
204  * entry to align the next ADS entry or dentry on an 8-byte boundary. */
205 static u64
206 ads_entry_total_length(const struct wim_ads_entry *entry)
207 {
208         u64 len = sizeof(struct wim_ads_entry_on_disk);
209         if (entry->stream_name_nbytes)
210                 len += entry->stream_name_nbytes + 2;
211         return (len + 7) & ~7;
212 }
213
214
215 static u64
216 _dentry_total_length(const struct wim_dentry *dentry, u64 length)
217 {
218         const struct wim_inode *inode = dentry->d_inode;
219         for (u16 i = 0; i < inode->i_num_ads; i++)
220                 length += ads_entry_total_length(&inode->i_ads_entries[i]);
221         return (length + 7) & ~7;
222 }
223
224 /* Calculate the aligned *total* length of an on-disk WIM dentry.  This includes
225  * all alternate data streams. */
226 u64
227 dentry_correct_total_length(const struct wim_dentry *dentry)
228 {
229         return _dentry_total_length(dentry,
230                                     dentry_correct_length_unaligned(dentry));
231 }
232
233 /* Like dentry_correct_total_length(), but use the existing dentry->length field
234  * instead of calculating its "correct" value. */
235 static u64
236 dentry_total_length(const struct wim_dentry *dentry)
237 {
238         return _dentry_total_length(dentry, dentry->length);
239 }
240
241 int
242 for_dentry_in_rbtree(struct rb_node *root,
243                      int (*visitor)(struct wim_dentry *, void *),
244                      void *arg)
245 {
246         int ret;
247         struct rb_node *node = root;
248         LIST_HEAD(stack);
249         while (1) {
250                 if (node) {
251                         list_add(&rbnode_dentry(node)->tmp_list, &stack);
252                         node = node->rb_left;
253                 } else {
254                         struct list_head *next;
255                         struct wim_dentry *dentry;
256
257                         next = stack.next;
258                         if (next == &stack)
259                                 return 0;
260                         dentry = container_of(next, struct wim_dentry, tmp_list);
261                         list_del(next);
262                         ret = visitor(dentry, arg);
263                         if (ret != 0)
264                                 return ret;
265                         node = dentry->rb_node.rb_right;
266                 }
267         }
268 }
269
270 static int
271 for_dentry_tree_in_rbtree_depth(struct rb_node *node,
272                                 int (*visitor)(struct wim_dentry*, void*),
273                                 void *arg)
274 {
275         int ret;
276         if (node) {
277                 ret = for_dentry_tree_in_rbtree_depth(node->rb_left,
278                                                       visitor, arg);
279                 if (ret != 0)
280                         return ret;
281                 ret = for_dentry_tree_in_rbtree_depth(node->rb_right,
282                                                       visitor, arg);
283                 if (ret != 0)
284                         return ret;
285                 ret = for_dentry_in_tree_depth(rbnode_dentry(node), visitor, arg);
286                 if (ret != 0)
287                         return ret;
288         }
289         return 0;
290 }
291
292 static int
293 for_dentry_tree_in_rbtree(struct rb_node *node,
294                           int (*visitor)(struct wim_dentry*, void*),
295                           void *arg)
296 {
297         int ret;
298         if (node) {
299                 ret = for_dentry_tree_in_rbtree(node->rb_left, visitor, arg);
300                 if (ret)
301                         return ret;
302                 ret = for_dentry_in_tree(rbnode_dentry(node), visitor, arg);
303                 if (ret)
304                         return ret;
305                 ret = for_dentry_tree_in_rbtree(node->rb_right, visitor, arg);
306                 if (ret)
307                         return ret;
308         }
309         return 0;
310 }
311
312 /* Calls a function on all directory entries in a WIM dentry tree.  Logically,
313  * this is a pre-order traversal (the function is called on a parent dentry
314  * before its children), but sibling dentries will be visited in order as well.
315  * */
316 int
317 for_dentry_in_tree(struct wim_dentry *root,
318                    int (*visitor)(struct wim_dentry*, void*), void *arg)
319 {
320         int ret;
321
322         if (!root)
323                 return 0;
324         ret = (*visitor)(root, arg);
325         if (ret)
326                 return ret;
327         return for_dentry_tree_in_rbtree(root->d_inode->i_children.rb_node,
328                                          visitor,
329                                          arg);
330 }
331
332 /* Like for_dentry_in_tree(), but the visitor function is always called on a
333  * dentry's children before on itself. */
334 int
335 for_dentry_in_tree_depth(struct wim_dentry *root,
336                          int (*visitor)(struct wim_dentry*, void*), void *arg)
337 {
338         int ret;
339
340         if (!root)
341                 return 0;
342         ret = for_dentry_tree_in_rbtree_depth(root->d_inode->i_children.rb_node,
343                                               visitor, arg);
344         if (ret)
345                 return ret;
346         return (*visitor)(root, arg);
347 }
348
349 /* Calculate the full path of @dentry.  The full path of its parent must have
350  * already been calculated, or it must be the root dentry. */
351 static int
352 calculate_dentry_full_path(struct wim_dentry *dentry)
353 {
354         tchar *full_path;
355         u32 full_path_nbytes;
356         int ret;
357
358         if (dentry->_full_path)
359                 return 0;
360
361         if (dentry_is_root(dentry)) {
362                 full_path = TSTRDUP(T("/"));
363                 if (!full_path)
364                         return WIMLIB_ERR_NOMEM;
365                 full_path_nbytes = 1 * sizeof(tchar);
366         } else {
367                 struct wim_dentry *parent;
368                 tchar *parent_full_path;
369                 u32 parent_full_path_nbytes;
370                 size_t filename_nbytes;
371
372                 parent = dentry->parent;
373                 if (dentry_is_root(parent)) {
374                         parent_full_path = T("");
375                         parent_full_path_nbytes = 0;
376                 } else {
377                         if (!parent->_full_path) {
378                                 ret = calculate_dentry_full_path(parent);
379                                 if (ret)
380                                         return ret;
381                         }
382                         parent_full_path = parent->_full_path;
383                         parent_full_path_nbytes = parent->full_path_nbytes;
384                 }
385
386                 /* Append this dentry's name as a tchar string to the full path
387                  * of the parent followed by the path separator */
388         #if TCHAR_IS_UTF16LE
389                 filename_nbytes = dentry->file_name_nbytes;
390         #else
391                 {
392                         int ret = utf16le_to_tstr_nbytes(dentry->file_name,
393                                                          dentry->file_name_nbytes,
394                                                          &filename_nbytes);
395                         if (ret)
396                                 return ret;
397                 }
398         #endif
399
400                 full_path_nbytes = parent_full_path_nbytes + sizeof(tchar) +
401                                    filename_nbytes;
402                 full_path = MALLOC(full_path_nbytes + sizeof(tchar));
403                 if (!full_path)
404                         return WIMLIB_ERR_NOMEM;
405                 memcpy(full_path, parent_full_path, parent_full_path_nbytes);
406                 full_path[parent_full_path_nbytes / sizeof(tchar)] = T('/');
407         #if TCHAR_IS_UTF16LE
408                 memcpy(&full_path[parent_full_path_nbytes / sizeof(tchar) + 1],
409                        dentry->file_name,
410                        filename_nbytes + sizeof(tchar));
411         #else
412                 utf16le_to_tstr_buf(dentry->file_name,
413                                     dentry->file_name_nbytes,
414                                     &full_path[parent_full_path_nbytes /
415                                                sizeof(tchar) + 1]);
416         #endif
417         }
418         dentry->_full_path = full_path;
419         dentry->full_path_nbytes= full_path_nbytes;
420         return 0;
421 }
422
423 static int
424 do_calculate_dentry_full_path(struct wim_dentry *dentry, void *_ignore)
425 {
426         return calculate_dentry_full_path(dentry);
427 }
428
429 int
430 calculate_dentry_tree_full_paths(struct wim_dentry *root)
431 {
432         return for_dentry_in_tree(root, do_calculate_dentry_full_path, NULL);
433 }
434
435 tchar *
436 dentry_full_path(struct wim_dentry *dentry)
437 {
438         calculate_dentry_full_path(dentry);
439         return dentry->_full_path;
440 }
441
442 static int
443 increment_subdir_offset(struct wim_dentry *dentry, void *subdir_offset_p)
444 {
445         *(u64*)subdir_offset_p += dentry_correct_total_length(dentry);
446         return 0;
447 }
448
449 static int
450 call_calculate_subdir_offsets(struct wim_dentry *dentry, void *subdir_offset_p)
451 {
452         calculate_subdir_offsets(dentry, subdir_offset_p);
453         return 0;
454 }
455
456 /*
457  * Recursively calculates the subdir offsets for a directory tree.
458  *
459  * @dentry:  The root of the directory tree.
460  * @subdir_offset_p:  The current subdirectory offset; i.e., the subdirectory
461  *                    offset for @dentry.
462  */
463 void
464 calculate_subdir_offsets(struct wim_dentry *dentry, u64 *subdir_offset_p)
465 {
466         struct rb_node *node;
467
468         dentry->subdir_offset = *subdir_offset_p;
469         node = dentry->d_inode->i_children.rb_node;
470         if (node) {
471                 /* Advance the subdir offset by the amount of space the children
472                  * of this dentry take up. */
473                 for_dentry_in_rbtree(node, increment_subdir_offset, subdir_offset_p);
474
475                 /* End-of-directory dentry on disk. */
476                 *subdir_offset_p += 8;
477
478                 /* Recursively call calculate_subdir_offsets() on all the
479                  * children. */
480                 for_dentry_in_rbtree(node, call_calculate_subdir_offsets, subdir_offset_p);
481         } else {
482                 /* On disk, childless directories have a valid subdir_offset
483                  * that points to an 8-byte end-of-directory dentry.  Regular
484                  * files or reparse points have a subdir_offset of 0. */
485                 if (dentry_is_directory(dentry))
486                         *subdir_offset_p += 8;
487                 else
488                         dentry->subdir_offset = 0;
489         }
490 }
491
492 static int
493 compare_utf16le_names(const utf16lechar *name1, size_t nbytes1,
494                       const utf16lechar *name2, size_t nbytes2)
495 {
496         int result = memcmp(name1, name2, min(nbytes1, nbytes2));
497         if (result)
498                 return result;
499         else
500                 return (int)nbytes1 - (int)nbytes2;
501 }
502
503 static int
504 dentry_compare_names(const struct wim_dentry *d1, const struct wim_dentry *d2)
505 {
506         return compare_utf16le_names(d1->file_name, d1->file_name_nbytes,
507                                      d2->file_name, d2->file_name_nbytes);
508 }
509
510
511 struct wim_dentry *
512 get_dentry_child_with_utf16le_name(const struct wim_dentry *dentry,
513                                    const utf16lechar *name,
514                                    size_t name_nbytes)
515 {
516         struct rb_node *node = dentry->d_inode->i_children.rb_node;
517         struct wim_dentry *child;
518         while (node) {
519                 child = rbnode_dentry(node);
520                 int result = compare_utf16le_names(name, name_nbytes,
521                                                    child->file_name,
522                                                    child->file_name_nbytes);
523                 if (result < 0)
524                         node = node->rb_left;
525                 else if (result > 0)
526                         node = node->rb_right;
527                 else
528                         return child;
529         }
530         return NULL;
531 }
532
533 /* Returns the child of @dentry that has the file name @name.  Returns NULL if
534  * no child has the name. */
535 struct wim_dentry *
536 get_dentry_child_with_name(const struct wim_dentry *dentry, const tchar *name)
537 {
538 #if TCHAR_IS_UTF16LE
539         return get_dentry_child_with_utf16le_name(dentry, name,
540                                                   tstrlen(name) * sizeof(tchar));
541 #else
542         utf16lechar *utf16le_name;
543         size_t utf16le_name_nbytes;
544         int ret;
545         struct wim_dentry *child;
546
547         ret = tstr_to_utf16le(name, tstrlen(name) * sizeof(tchar),
548                               &utf16le_name, &utf16le_name_nbytes);
549         if (ret) {
550                 child = NULL;
551         } else {
552                 child = get_dentry_child_with_utf16le_name(dentry,
553                                                            utf16le_name,
554                                                            utf16le_name_nbytes);
555                 FREE(utf16le_name);
556         }
557         return child;
558 #endif
559 }
560
561 static struct wim_dentry *
562 get_dentry_utf16le(WIMStruct *wim, const utf16lechar *path)
563 {
564         struct wim_dentry *cur_dentry, *parent_dentry;
565         const utf16lechar *p, *pp;
566
567         cur_dentry = parent_dentry = wim_root_dentry(wim);
568         if (!cur_dentry) {
569                 errno = ENOENT;
570                 return NULL;
571         }
572         p = path;
573         while (1) {
574                 while (*p == cpu_to_le16('/'))
575                         p++;
576                 if (*p == cpu_to_le16('\0'))
577                         break;
578                 pp = p;
579                 while (*pp != cpu_to_le16('/') && *pp != cpu_to_le16('\0'))
580                         pp++;
581
582                 cur_dentry = get_dentry_child_with_utf16le_name(parent_dentry, p,
583                                                                 (void*)pp - (void*)p);
584                 if (cur_dentry == NULL)
585                         break;
586                 p = pp;
587                 parent_dentry = cur_dentry;
588         }
589         if (cur_dentry == NULL) {
590                 if (dentry_is_directory(parent_dentry))
591                         errno = ENOENT;
592                 else
593                         errno = ENOTDIR;
594         }
595         return cur_dentry;
596 }
597
598 /* Returns the dentry corresponding to the @path, or NULL if there is no such
599  * dentry. */
600 struct wim_dentry *
601 get_dentry(WIMStruct *wim, const tchar *path)
602 {
603 #if TCHAR_IS_UTF16LE
604         return get_dentry_utf16le(wim, path);
605 #else
606         utf16lechar *path_utf16le;
607         size_t path_utf16le_nbytes;
608         int ret;
609         struct wim_dentry *dentry;
610
611         ret = tstr_to_utf16le(path, tstrlen(path) * sizeof(tchar),
612                               &path_utf16le, &path_utf16le_nbytes);
613         if (ret)
614                 return NULL;
615         dentry = get_dentry_utf16le(wim, path_utf16le);
616         FREE(path_utf16le);
617         return dentry;
618 #endif
619 }
620
621 struct wim_inode *
622 wim_pathname_to_inode(WIMStruct *wim, const tchar *path)
623 {
624         struct wim_dentry *dentry;
625         dentry = get_dentry(wim, path);
626         if (dentry)
627                 return dentry->d_inode;
628         else
629                 return NULL;
630 }
631
632 /* Takes in a path of length @len in @buf, and transforms it into a string for
633  * the path of its parent directory. */
634 static void
635 to_parent_name(tchar *buf, size_t len)
636 {
637         ssize_t i = (ssize_t)len - 1;
638         while (i >= 0 && buf[i] == T('/'))
639                 i--;
640         while (i >= 0 && buf[i] != T('/'))
641                 i--;
642         while (i >= 0 && buf[i] == T('/'))
643                 i--;
644         buf[i + 1] = T('\0');
645 }
646
647 /* Returns the dentry that corresponds to the parent directory of @path, or NULL
648  * if the dentry is not found. */
649 struct wim_dentry *
650 get_parent_dentry(WIMStruct *wim, const tchar *path)
651 {
652         size_t path_len = tstrlen(path);
653         tchar buf[path_len + 1];
654
655         tmemcpy(buf, path, path_len + 1);
656         to_parent_name(buf, path_len);
657         return get_dentry(wim, buf);
658 }
659
660 /* Prints the full path of a dentry. */
661 int
662 print_dentry_full_path(struct wim_dentry *dentry, void *_ignore)
663 {
664         int ret = calculate_dentry_full_path(dentry);
665         if (ret)
666                 return ret;
667         tprintf(T("%"TS"\n"), dentry->_full_path);
668         return 0;
669 }
670
671 /* We want to be able to show the names of the file attribute flags that are
672  * set. */
673 struct file_attr_flag {
674         u32 flag;
675         const tchar *name;
676 };
677 struct file_attr_flag file_attr_flags[] = {
678         {FILE_ATTRIBUTE_READONLY,           T("READONLY")},
679         {FILE_ATTRIBUTE_HIDDEN,             T("HIDDEN")},
680         {FILE_ATTRIBUTE_SYSTEM,             T("SYSTEM")},
681         {FILE_ATTRIBUTE_DIRECTORY,          T("DIRECTORY")},
682         {FILE_ATTRIBUTE_ARCHIVE,            T("ARCHIVE")},
683         {FILE_ATTRIBUTE_DEVICE,             T("DEVICE")},
684         {FILE_ATTRIBUTE_NORMAL,             T("NORMAL")},
685         {FILE_ATTRIBUTE_TEMPORARY,          T("TEMPORARY")},
686         {FILE_ATTRIBUTE_SPARSE_FILE,        T("SPARSE_FILE")},
687         {FILE_ATTRIBUTE_REPARSE_POINT,      T("REPARSE_POINT")},
688         {FILE_ATTRIBUTE_COMPRESSED,         T("COMPRESSED")},
689         {FILE_ATTRIBUTE_OFFLINE,            T("OFFLINE")},
690         {FILE_ATTRIBUTE_NOT_CONTENT_INDEXED,T("NOT_CONTENT_INDEXED")},
691         {FILE_ATTRIBUTE_ENCRYPTED,          T("ENCRYPTED")},
692         {FILE_ATTRIBUTE_VIRTUAL,            T("VIRTUAL")},
693 };
694
695 /* Prints a directory entry.  @lookup_table is a pointer to the lookup table, if
696  * available.  If the dentry is unresolved and the lookup table is NULL, the
697  * lookup table entries will not be printed.  Otherwise, they will be. */
698 int
699 print_dentry(struct wim_dentry *dentry, void *lookup_table)
700 {
701         const u8 *hash;
702         struct wim_lookup_table_entry *lte;
703         const struct wim_inode *inode = dentry->d_inode;
704         tchar buf[50];
705
706         tprintf(T("[DENTRY]\n"));
707         tprintf(T("Length            = %"PRIu64"\n"), dentry->length);
708         tprintf(T("Attributes        = 0x%x\n"), inode->i_attributes);
709         for (size_t i = 0; i < ARRAY_LEN(file_attr_flags); i++)
710                 if (file_attr_flags[i].flag & inode->i_attributes)
711                         tprintf(T("    FILE_ATTRIBUTE_%"TS" is set\n"),
712                                 file_attr_flags[i].name);
713         tprintf(T("Security ID       = %d\n"), inode->i_security_id);
714         tprintf(T("Subdir offset     = %"PRIu64"\n"), dentry->subdir_offset);
715
716         wim_timestamp_to_str(inode->i_creation_time, buf, sizeof(buf));
717         tprintf(T("Creation Time     = %"TS"\n"), buf);
718
719         wim_timestamp_to_str(inode->i_last_access_time, buf, sizeof(buf));
720         tprintf(T("Last Access Time  = %"TS"\n"), buf);
721
722         wim_timestamp_to_str(inode->i_last_write_time, buf, sizeof(buf));
723         tprintf(T("Last Write Time   = %"TS"\n"), buf);
724
725         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
726                 tprintf(T("Reparse Tag       = 0x%"PRIx32"\n"), inode->i_reparse_tag);
727                 tprintf(T("Reparse Point Flags = 0x%"PRIx16"\n"),
728                         inode->i_not_rpfixed);
729                 tprintf(T("Reparse Point Unknown 2 = 0x%"PRIx32"\n"),
730                         inode->i_rp_unknown_2);
731         }
732         tprintf(T("Reparse Point Unknown 1 = 0x%"PRIx32"\n"),
733                 inode->i_rp_unknown_1);
734         tprintf(T("Hard Link Group   = 0x%"PRIx64"\n"), inode->i_ino);
735         tprintf(T("Hard Link Group Size = %"PRIu32"\n"), inode->i_nlink);
736         tprintf(T("Number of Alternate Data Streams = %hu\n"), inode->i_num_ads);
737         if (dentry_has_long_name(dentry))
738                 wimlib_printf(T("Filename = \"%"WS"\"\n"), dentry->file_name);
739         if (dentry_has_short_name(dentry))
740                 wimlib_printf(T("Short Name \"%"WS"\"\n"), dentry->short_name);
741         if (dentry->_full_path)
742                 tprintf(T("Full Path = \"%"TS"\"\n"), dentry->_full_path);
743
744         lte = inode_stream_lte(dentry->d_inode, 0, lookup_table);
745         if (lte) {
746                 print_lookup_table_entry(lte, stdout);
747         } else {
748                 hash = inode_stream_hash(inode, 0);
749                 if (hash) {
750                         tprintf(T("Hash              = 0x"));
751                         print_hash(hash, stdout);
752                         tputchar(T('\n'));
753                         tputchar(T('\n'));
754                 }
755         }
756         for (u16 i = 0; i < inode->i_num_ads; i++) {
757                 tprintf(T("[Alternate Stream Entry %u]\n"), i);
758                 wimlib_printf(T("Name = \"%"WS"\"\n"),
759                               inode->i_ads_entries[i].stream_name);
760                 tprintf(T("Name Length (UTF16 bytes) = %hu\n"),
761                        inode->i_ads_entries[i].stream_name_nbytes);
762                 hash = inode_stream_hash(inode, i + 1);
763                 if (hash) {
764                         tprintf(T("Hash              = 0x"));
765                         print_hash(hash, stdout);
766                         tputchar(T('\n'));
767                 }
768                 print_lookup_table_entry(inode_stream_lte(inode, i + 1, lookup_table),
769                                          stdout);
770         }
771         return 0;
772 }
773
774 /* Initializations done on every `struct wim_dentry'. */
775 static void
776 dentry_common_init(struct wim_dentry *dentry)
777 {
778         memset(dentry, 0, sizeof(struct wim_dentry));
779 }
780
781 struct wim_inode *
782 new_timeless_inode(void)
783 {
784         struct wim_inode *inode = CALLOC(1, sizeof(struct wim_inode));
785         if (inode) {
786                 inode->i_security_id = -1;
787                 inode->i_nlink = 1;
788                 inode->i_next_stream_id = 1;
789                 inode->i_not_rpfixed = 1;
790                 INIT_LIST_HEAD(&inode->i_list);
791         #ifdef WITH_FUSE
792                 if (pthread_mutex_init(&inode->i_mutex, NULL) != 0) {
793                         ERROR_WITH_ERRNO("Error initializing mutex");
794                         FREE(inode);
795                         return NULL;
796                 }
797         #endif
798                 INIT_LIST_HEAD(&inode->i_dentry);
799         }
800         return inode;
801 }
802
803 static struct wim_inode *
804 new_inode(void)
805 {
806         struct wim_inode *inode = new_timeless_inode();
807         if (inode) {
808                 u64 now = get_wim_timestamp();
809                 inode->i_creation_time = now;
810                 inode->i_last_access_time = now;
811                 inode->i_last_write_time = now;
812         }
813         return inode;
814 }
815
816 /* Creates an unlinked directory entry. */
817 int
818 new_dentry(const tchar *name, struct wim_dentry **dentry_ret)
819 {
820         struct wim_dentry *dentry;
821         int ret;
822
823         dentry = MALLOC(sizeof(struct wim_dentry));
824         if (!dentry)
825                 return WIMLIB_ERR_NOMEM;
826
827         dentry_common_init(dentry);
828         ret = set_dentry_name(dentry, name);
829         if (ret == 0) {
830                 dentry->parent = dentry;
831                 *dentry_ret = dentry;
832         } else {
833                 FREE(dentry);
834                 ERROR("Failed to set name on new dentry with name \"%"TS"\"",
835                       name);
836         }
837         return ret;
838 }
839
840
841 static int
842 _new_dentry_with_inode(const tchar *name, struct wim_dentry **dentry_ret,
843                         bool timeless)
844 {
845         struct wim_dentry *dentry;
846         int ret;
847
848         ret = new_dentry(name, &dentry);
849         if (ret)
850                 return ret;
851
852         if (timeless)
853                 dentry->d_inode = new_timeless_inode();
854         else
855                 dentry->d_inode = new_inode();
856         if (!dentry->d_inode) {
857                 free_dentry(dentry);
858                 return WIMLIB_ERR_NOMEM;
859         }
860
861         inode_add_dentry(dentry, dentry->d_inode);
862         *dentry_ret = dentry;
863         return 0;
864 }
865
866 int
867 new_dentry_with_timeless_inode(const tchar *name, struct wim_dentry **dentry_ret)
868 {
869         return _new_dentry_with_inode(name, dentry_ret, true);
870 }
871
872 int
873 new_dentry_with_inode(const tchar *name, struct wim_dentry **dentry_ret)
874 {
875         return _new_dentry_with_inode(name, dentry_ret, false);
876 }
877
878 int
879 new_filler_directory(const tchar *name, struct wim_dentry **dentry_ret)
880 {
881         int ret;
882         struct wim_dentry *dentry;
883
884         DEBUG("Creating filler directory \"%"TS"\"", name);
885         ret = new_dentry_with_inode(name, &dentry);
886         if (ret)
887                 return ret;
888         /* Leave the inode number as 0; this is allowed for non
889          * hard-linked files. */
890         dentry->d_inode->i_resolved = 1;
891         dentry->d_inode->i_attributes = FILE_ATTRIBUTE_DIRECTORY;
892         *dentry_ret = dentry;
893         return 0;
894 }
895
896 static int
897 init_ads_entry(struct wim_ads_entry *ads_entry, const void *name,
898                size_t name_nbytes, bool is_utf16le)
899 {
900         int ret = 0;
901         memset(ads_entry, 0, sizeof(*ads_entry));
902
903         if (is_utf16le) {
904                 utf16lechar *p = MALLOC(name_nbytes + sizeof(utf16lechar));
905                 if (!p)
906                         return WIMLIB_ERR_NOMEM;
907                 memcpy(p, name, name_nbytes);
908                 p[name_nbytes / 2] = cpu_to_le16(0);
909                 ads_entry->stream_name = p;
910                 ads_entry->stream_name_nbytes = name_nbytes;
911         } else {
912                 if (name && *(const tchar*)name != T('\0')) {
913                         ret = get_utf16le_name(name, &ads_entry->stream_name,
914                                                &ads_entry->stream_name_nbytes);
915                 }
916         }
917         return ret;
918 }
919
920 static void
921 destroy_ads_entry(struct wim_ads_entry *ads_entry)
922 {
923         FREE(ads_entry->stream_name);
924 }
925
926 /* Frees an inode. */
927 void
928 free_inode(struct wim_inode *inode)
929 {
930         if (inode) {
931                 if (inode->i_ads_entries) {
932                         for (u16 i = 0; i < inode->i_num_ads; i++)
933                                 destroy_ads_entry(&inode->i_ads_entries[i]);
934                         FREE(inode->i_ads_entries);
935                 }
936         #ifdef WITH_FUSE
937                 wimlib_assert(inode->i_num_opened_fds == 0);
938                 FREE(inode->i_fds);
939                 pthread_mutex_destroy(&inode->i_mutex);
940         #endif
941                 /* HACK: This may instead delete the inode from i_list, but the
942                  * hlist_del() behaves the same as list_del(). */
943                 hlist_del(&inode->i_hlist);
944                 FREE(inode->i_extracted_file);
945                 FREE(inode);
946         }
947 }
948
949 /* Decrements link count on an inode and frees it if the link count reaches 0.
950  * */
951 static void
952 put_inode(struct wim_inode *inode)
953 {
954         wimlib_assert(inode->i_nlink != 0);
955         if (--inode->i_nlink == 0) {
956         #ifdef WITH_FUSE
957                 if (inode->i_num_opened_fds == 0)
958         #endif
959                 {
960                         free_inode(inode);
961                 }
962         }
963 }
964
965 /* Frees a WIM dentry.
966  *
967  * The corresponding inode (if any) is freed only if its link count is
968  * decremented to 0.
969  */
970 void
971 free_dentry(struct wim_dentry *dentry)
972 {
973         if (dentry) {
974                 FREE(dentry->file_name);
975                 FREE(dentry->short_name);
976                 FREE(dentry->_full_path);
977                 if (dentry->d_inode)
978                         put_inode(dentry->d_inode);
979                 FREE(dentry);
980         }
981 }
982
983 /* This function is passed as an argument to for_dentry_in_tree_depth() in order
984  * to free a directory tree. */
985 static int
986 do_free_dentry(struct wim_dentry *dentry, void *_lookup_table)
987 {
988         struct wim_lookup_table *lookup_table = _lookup_table;
989
990         if (lookup_table) {
991                 struct wim_inode *inode = dentry->d_inode;
992                 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
993                         struct wim_lookup_table_entry *lte;
994
995                         lte = inode_stream_lte(inode, i, lookup_table);
996                         if (lte)
997                                 lte_decrement_refcnt(lte, lookup_table);
998                 }
999         }
1000         free_dentry(dentry);
1001         return 0;
1002 }
1003
1004 /*
1005  * Unlinks and frees a dentry tree.
1006  *
1007  * @root:               The root of the tree.
1008  * @lookup_table:       The lookup table for dentries.  If non-NULL, the
1009  *                      reference counts in the lookup table for the lookup
1010  *                      table entries corresponding to the dentries will be
1011  *                      decremented.
1012  */
1013 void
1014 free_dentry_tree(struct wim_dentry *root, struct wim_lookup_table *lookup_table)
1015 {
1016         for_dentry_in_tree_depth(root, do_free_dentry, lookup_table);
1017 }
1018
1019 /*
1020  * Links a dentry into the directory tree.
1021  *
1022  * @parent: The dentry that will be the parent of @child.
1023  * @child: The dentry to link.
1024  *
1025  * Returns non-NULL if a duplicate dentry was detected.
1026  */
1027 struct wim_dentry *
1028 dentry_add_child(struct wim_dentry * restrict parent,
1029                  struct wim_dentry * restrict child)
1030 {
1031         wimlib_assert(dentry_is_directory(parent));
1032         wimlib_assert(parent != child);
1033
1034         struct rb_root *root = &parent->d_inode->i_children;
1035         struct rb_node **new = &(root->rb_node);
1036         struct rb_node *rb_parent = NULL;
1037
1038         while (*new) {
1039                 struct wim_dentry *this = rbnode_dentry(*new);
1040                 int result = dentry_compare_names(child, this);
1041
1042                 rb_parent = *new;
1043
1044                 if (result < 0)
1045                         new = &((*new)->rb_left);
1046                 else if (result > 0)
1047                         new = &((*new)->rb_right);
1048                 else
1049                         return this;
1050         }
1051         child->parent = parent;
1052         rb_link_node(&child->rb_node, rb_parent, new);
1053         rb_insert_color(&child->rb_node, root);
1054         return NULL;
1055 }
1056
1057 /* Unlink a WIM dentry from the directory entry tree. */
1058 void
1059 unlink_dentry(struct wim_dentry *dentry)
1060 {
1061         if (!dentry_is_root(dentry))
1062                 rb_erase(&dentry->rb_node, &dentry->parent->d_inode->i_children);
1063 }
1064
1065 /*
1066  * Returns the alternate data stream entry belonging to @inode that has the
1067  * stream name @stream_name.
1068  */
1069 struct wim_ads_entry *
1070 inode_get_ads_entry(struct wim_inode *inode, const tchar *stream_name,
1071                     u16 *idx_ret)
1072 {
1073         if (inode->i_num_ads == 0) {
1074                 return NULL;
1075         } else {
1076                 size_t stream_name_utf16le_nbytes;
1077                 u16 i;
1078                 struct wim_ads_entry *result;
1079
1080         #if TCHAR_IS_UTF16LE
1081                 const utf16lechar *stream_name_utf16le;
1082
1083                 stream_name_utf16le = stream_name;
1084                 stream_name_utf16le_nbytes = tstrlen(stream_name) * sizeof(tchar);
1085         #else
1086                 utf16lechar *stream_name_utf16le;
1087
1088                 {
1089                         int ret = tstr_to_utf16le(stream_name,
1090                                                   tstrlen(stream_name) *
1091                                                       sizeof(tchar),
1092                                                   &stream_name_utf16le,
1093                                                   &stream_name_utf16le_nbytes);
1094                         if (ret)
1095                                 return NULL;
1096                 }
1097         #endif
1098                 i = 0;
1099                 result = NULL;
1100                 do {
1101                         if (ads_entry_has_name(&inode->i_ads_entries[i],
1102                                                stream_name_utf16le,
1103                                                stream_name_utf16le_nbytes))
1104                         {
1105                                 if (idx_ret)
1106                                         *idx_ret = i;
1107                                 result = &inode->i_ads_entries[i];
1108                                 break;
1109                         }
1110                 } while (++i != inode->i_num_ads);
1111         #if !TCHAR_IS_UTF16LE
1112                 FREE(stream_name_utf16le);
1113         #endif
1114                 return result;
1115         }
1116 }
1117
1118 static struct wim_ads_entry *
1119 do_inode_add_ads(struct wim_inode *inode, const void *stream_name,
1120                  size_t stream_name_nbytes, bool is_utf16le)
1121 {
1122         u16 num_ads;
1123         struct wim_ads_entry *ads_entries;
1124         struct wim_ads_entry *new_entry;
1125
1126         if (inode->i_num_ads >= 0xfffe) {
1127                 ERROR("Too many alternate data streams in one inode!");
1128                 return NULL;
1129         }
1130         num_ads = inode->i_num_ads + 1;
1131         ads_entries = REALLOC(inode->i_ads_entries,
1132                               num_ads * sizeof(inode->i_ads_entries[0]));
1133         if (!ads_entries) {
1134                 ERROR("Failed to allocate memory for new alternate data stream");
1135                 return NULL;
1136         }
1137         inode->i_ads_entries = ads_entries;
1138
1139         new_entry = &inode->i_ads_entries[num_ads - 1];
1140         if (init_ads_entry(new_entry, stream_name, stream_name_nbytes, is_utf16le))
1141                 return NULL;
1142         new_entry->stream_id = inode->i_next_stream_id++;
1143         inode->i_num_ads = num_ads;
1144         return new_entry;
1145 }
1146
1147 struct wim_ads_entry *
1148 inode_add_ads_utf16le(struct wim_inode *inode,
1149                       const utf16lechar *stream_name,
1150                       size_t stream_name_nbytes)
1151 {
1152         DEBUG("Add alternate data stream \"%"WS"\"", stream_name);
1153         return do_inode_add_ads(inode, stream_name, stream_name_nbytes, true);
1154 }
1155
1156 /*
1157  * Add an alternate stream entry to a WIM inode and return a pointer to it, or
1158  * NULL if memory could not be allocated.
1159  */
1160 struct wim_ads_entry *
1161 inode_add_ads(struct wim_inode *inode, const tchar *stream_name)
1162 {
1163         DEBUG("Add alternate data stream \"%"TS"\"", stream_name);
1164         return do_inode_add_ads(inode, stream_name,
1165                                 tstrlen(stream_name) * sizeof(tchar),
1166                                 TCHAR_IS_UTF16LE);
1167 }
1168
1169 static struct wim_lookup_table_entry *
1170 add_stream_from_data_buffer(const void *buffer, size_t size,
1171                             struct wim_lookup_table *lookup_table)
1172 {
1173         u8 hash[SHA1_HASH_SIZE];
1174         struct wim_lookup_table_entry *lte, *existing_lte;
1175
1176         sha1_buffer(buffer, size, hash);
1177         existing_lte = __lookup_resource(lookup_table, hash);
1178         if (existing_lte) {
1179                 wimlib_assert(wim_resource_size(existing_lte) == size);
1180                 lte = existing_lte;
1181                 lte->refcnt++;
1182         } else {
1183                 void *buffer_copy;
1184                 lte = new_lookup_table_entry();
1185                 if (!lte)
1186                         return NULL;
1187                 buffer_copy = memdup(buffer, size);
1188                 if (!buffer_copy) {
1189                         free_lookup_table_entry(lte);
1190                         return NULL;
1191                 }
1192                 lte->resource_location            = RESOURCE_IN_ATTACHED_BUFFER;
1193                 lte->attached_buffer              = buffer_copy;
1194                 lte->resource_entry.original_size = size;
1195                 copy_hash(lte->hash, hash);
1196                 lookup_table_insert(lookup_table, lte);
1197         }
1198         return lte;
1199 }
1200
1201 int
1202 inode_add_ads_with_data(struct wim_inode *inode, const tchar *name,
1203                         const void *value, size_t size,
1204                         struct wim_lookup_table *lookup_table)
1205 {
1206         struct wim_ads_entry *new_ads_entry;
1207
1208         wimlib_assert(inode->i_resolved);
1209
1210         new_ads_entry = inode_add_ads(inode, name);
1211         if (!new_ads_entry)
1212                 return WIMLIB_ERR_NOMEM;
1213
1214         new_ads_entry->lte = add_stream_from_data_buffer(value, size,
1215                                                          lookup_table);
1216         if (!new_ads_entry->lte) {
1217                 inode_remove_ads(inode, new_ads_entry - inode->i_ads_entries,
1218                                  lookup_table);
1219                 return WIMLIB_ERR_NOMEM;
1220         }
1221         return 0;
1222 }
1223
1224 /* Set the unnamed stream of a WIM inode, given a data buffer containing the
1225  * stream contents. */
1226 int
1227 inode_set_unnamed_stream(struct wim_inode *inode, const void *data, size_t len,
1228                          struct wim_lookup_table *lookup_table)
1229 {
1230         inode->i_lte = add_stream_from_data_buffer(data, len, lookup_table);
1231         if (!inode->i_lte)
1232                 return WIMLIB_ERR_NOMEM;
1233         inode->i_resolved = 1;
1234         return 0;
1235 }
1236
1237 /* Remove an alternate data stream from a WIM inode  */
1238 void
1239 inode_remove_ads(struct wim_inode *inode, u16 idx,
1240                  struct wim_lookup_table *lookup_table)
1241 {
1242         struct wim_ads_entry *ads_entry;
1243         struct wim_lookup_table_entry *lte;
1244
1245         wimlib_assert(idx < inode->i_num_ads);
1246         wimlib_assert(inode->i_resolved);
1247
1248         ads_entry = &inode->i_ads_entries[idx];
1249
1250         DEBUG("Remove alternate data stream \"%"WS"\"", ads_entry->stream_name);
1251
1252         lte = ads_entry->lte;
1253         if (lte)
1254                 lte_decrement_refcnt(lte, lookup_table);
1255
1256         destroy_ads_entry(ads_entry);
1257
1258         memmove(&inode->i_ads_entries[idx],
1259                 &inode->i_ads_entries[idx + 1],
1260                 (inode->i_num_ads - idx - 1) * sizeof(inode->i_ads_entries[0]));
1261         inode->i_num_ads--;
1262 }
1263
1264 #ifndef __WIN32__
1265 int
1266 inode_get_unix_data(const struct wim_inode *inode,
1267                     struct wimlib_unix_data *unix_data,
1268                     u16 *stream_idx_ret)
1269 {
1270         const struct wim_ads_entry *ads_entry;
1271         const struct wim_lookup_table_entry *lte;
1272         size_t size;
1273         int ret;
1274
1275         wimlib_assert(inode->i_resolved);
1276
1277         ads_entry = inode_get_ads_entry((struct wim_inode*)inode,
1278                                         WIMLIB_UNIX_DATA_TAG, NULL);
1279         if (!ads_entry)
1280                 return NO_UNIX_DATA;
1281
1282         if (stream_idx_ret)
1283                 *stream_idx_ret = ads_entry - inode->i_ads_entries;
1284
1285         lte = ads_entry->lte;
1286         if (!lte)
1287                 return NO_UNIX_DATA;
1288
1289         size = wim_resource_size(lte);
1290         if (size != sizeof(struct wimlib_unix_data))
1291                 return BAD_UNIX_DATA;
1292
1293         ret = read_full_resource_into_buf(lte, unix_data);
1294         if (ret)
1295                 return ret;
1296
1297         if (unix_data->version != 0)
1298                 return BAD_UNIX_DATA;
1299         return 0;
1300 }
1301
1302 int
1303 inode_set_unix_data(struct wim_inode *inode, uid_t uid, gid_t gid, mode_t mode,
1304                     struct wim_lookup_table *lookup_table, int which)
1305 {
1306         struct wimlib_unix_data unix_data;
1307         int ret;
1308         bool have_good_unix_data = false;
1309         bool have_unix_data = false;
1310         u16 stream_idx;
1311
1312         if (!(which & UNIX_DATA_CREATE)) {
1313                 ret = inode_get_unix_data(inode, &unix_data, &stream_idx);
1314                 if (ret == 0 || ret == BAD_UNIX_DATA || ret > 0)
1315                         have_unix_data = true;
1316                 if (ret == 0)
1317                         have_good_unix_data = true;
1318         }
1319         unix_data.version = 0;
1320         if (which & UNIX_DATA_UID || !have_good_unix_data)
1321                 unix_data.uid = uid;
1322         if (which & UNIX_DATA_GID || !have_good_unix_data)
1323                 unix_data.gid = gid;
1324         if (which & UNIX_DATA_MODE || !have_good_unix_data)
1325                 unix_data.mode = mode;
1326         ret = inode_add_ads_with_data(inode, WIMLIB_UNIX_DATA_TAG,
1327                                       &unix_data,
1328                                       sizeof(struct wimlib_unix_data),
1329                                       lookup_table);
1330         if (ret == 0 && have_unix_data)
1331                 inode_remove_ads(inode, stream_idx, lookup_table);
1332         return ret;
1333 }
1334 #endif /* !__WIN32__ */
1335
1336 /* Replace weird characters in filenames and alternate data stream names.
1337  *
1338  * In particular we do not want the path separator to appear in any names, as
1339  * that would make it possible for a "malicious" WIM to extract itself to any
1340  * location it wanted to. */
1341 static void
1342 replace_forbidden_characters(utf16lechar *name)
1343 {
1344         utf16lechar *p;
1345
1346         for (p = name; *p; p++) {
1347         #ifdef __WIN32__
1348                 if (wcschr(L"<>:\"/\\|?*", (wchar_t)*p))
1349         #else
1350                 if (*p == cpu_to_le16('/'))
1351         #endif
1352                 {
1353                         if (name) {
1354                                 WARNING("File, directory, or stream name \"%"WS"\"\n"
1355                                         "          contains forbidden characters; "
1356                                         "substituting replacement characters.",
1357                                         name);
1358                                 name = NULL;
1359                         }
1360                 #ifdef __WIN32__
1361                         *p = cpu_to_le16(0xfffd);
1362                 #else
1363                         *p = cpu_to_le16('?');
1364                 #endif
1365                 }
1366         }
1367 }
1368
1369 /*
1370  * Reads the alternate data stream entries of a WIM dentry.
1371  *
1372  * @p:  Pointer to buffer that starts with the first alternate stream entry.
1373  *
1374  * @inode:      Inode to load the alternate data streams into.
1375  *              @inode->i_num_ads must have been set to the number of
1376  *              alternate data streams that are expected.
1377  *
1378  * @remaining_size:     Number of bytes of data remaining in the buffer pointed
1379  *                      to by @p.
1380  *
1381  *
1382  * Return 0 on success or nonzero on failure.  On success, inode->i_ads_entries
1383  * is set to an array of `struct wim_ads_entry's of length inode->i_num_ads.  On
1384  * failure, @inode is not modified.
1385  */
1386 static int
1387 read_ads_entries(const u8 * restrict p, struct wim_inode * restrict inode,
1388                  size_t nbytes_remaining)
1389 {
1390         u16 num_ads;
1391         struct wim_ads_entry *ads_entries;
1392         int ret;
1393
1394         BUILD_BUG_ON(sizeof(struct wim_ads_entry_on_disk) != WIM_ADS_ENTRY_DISK_SIZE);
1395
1396         /* Allocate an array for our in-memory representation of the alternate
1397          * data stream entries. */
1398         num_ads = inode->i_num_ads;
1399         ads_entries = CALLOC(num_ads, sizeof(inode->i_ads_entries[0]));
1400         if (!ads_entries)
1401                 goto out_of_memory;
1402
1403         /* Read the entries into our newly allocated buffer. */
1404         for (u16 i = 0; i < num_ads; i++) {
1405                 u64 length;
1406                 struct wim_ads_entry *cur_entry;
1407                 const struct wim_ads_entry_on_disk *disk_entry =
1408                         (const struct wim_ads_entry_on_disk*)p;
1409
1410                 cur_entry = &ads_entries[i];
1411                 ads_entries[i].stream_id = i + 1;
1412
1413                 /* Do we have at least the size of the fixed-length data we know
1414                  * need? */
1415                 if (nbytes_remaining < sizeof(struct wim_ads_entry_on_disk))
1416                         goto out_invalid;
1417
1418                 /* Read the length field */
1419                 length = le64_to_cpu(disk_entry->length);
1420
1421                 /* Make sure the length field is neither so small it doesn't
1422                  * include all the fixed-length data nor so large it overflows
1423                  * the metadata resource buffer. */
1424                 if (length < sizeof(struct wim_ads_entry_on_disk) ||
1425                     length > nbytes_remaining)
1426                         goto out_invalid;
1427
1428                 /* Read the rest of the fixed-length data. */
1429
1430                 cur_entry->reserved = le64_to_cpu(disk_entry->reserved);
1431                 copy_hash(cur_entry->hash, disk_entry->hash);
1432                 cur_entry->stream_name_nbytes = le16_to_cpu(disk_entry->stream_name_nbytes);
1433
1434                 /* If stream_name_nbytes != 0, this is a named stream.
1435                  * Otherwise this is an unnamed stream, or in some cases (bugs
1436                  * in Microsoft's software I guess) a meaningless entry
1437                  * distinguished from the real unnamed stream entry, if any, by
1438                  * the fact that the real unnamed stream entry has a nonzero
1439                  * hash field. */
1440                 if (cur_entry->stream_name_nbytes) {
1441                         /* The name is encoded in UTF16-LE, which uses 2-byte
1442                          * coding units, so the length of the name had better be
1443                          * an even number of bytes... */
1444                         if (cur_entry->stream_name_nbytes & 1)
1445                                 goto out_invalid;
1446
1447                         /* Add the length of the stream name to get the length
1448                          * we actually need to read.  Make sure this isn't more
1449                          * than the specified length of the entry. */
1450                         if (sizeof(struct wim_ads_entry_on_disk) +
1451                             cur_entry->stream_name_nbytes > length)
1452                                 goto out_invalid;
1453
1454                         cur_entry->stream_name = MALLOC(cur_entry->stream_name_nbytes + 2);
1455                         if (!cur_entry->stream_name)
1456                                 goto out_of_memory;
1457
1458                         memcpy(cur_entry->stream_name,
1459                                disk_entry->stream_name,
1460                                cur_entry->stream_name_nbytes);
1461                         cur_entry->stream_name[cur_entry->stream_name_nbytes / 2] = cpu_to_le16(0);
1462                         replace_forbidden_characters(cur_entry->stream_name);
1463                 }
1464
1465                 /* It's expected that the size of every ADS entry is a multiple
1466                  * of 8.  However, to be safe, I'm allowing the possibility of
1467                  * an ADS entry at the very end of the metadata resource ending
1468                  * un-aligned.  So although we still need to increment the input
1469                  * pointer by @length to reach the next ADS entry, it's possible
1470                  * that less than @length is actually remaining in the metadata
1471                  * resource. We should set the remaining bytes to 0 if this
1472                  * happens. */
1473                 length = (length + 7) & ~(u64)7;
1474                 p += length;
1475                 if (nbytes_remaining < length)
1476                         nbytes_remaining = 0;
1477                 else
1478                         nbytes_remaining -= length;
1479         }
1480         inode->i_ads_entries = ads_entries;
1481         inode->i_next_stream_id = inode->i_num_ads + 1;
1482         ret = 0;
1483         goto out;
1484 out_of_memory:
1485         ret = WIMLIB_ERR_NOMEM;
1486         goto out_free_ads_entries;
1487 out_invalid:
1488         ERROR("An alternate data stream entry is invalid");
1489         ret = WIMLIB_ERR_INVALID_DENTRY;
1490 out_free_ads_entries:
1491         if (ads_entries) {
1492                 for (u16 i = 0; i < num_ads; i++)
1493                         destroy_ads_entry(&ads_entries[i]);
1494                 FREE(ads_entries);
1495         }
1496 out:
1497         return ret;
1498 }
1499
1500 /*
1501  * Reads a WIM directory entry, including all alternate data stream entries that
1502  * follow it, from the WIM image's metadata resource.
1503  *
1504  * @metadata_resource:
1505  *              Pointer to the metadata resource buffer.
1506  *
1507  * @metadata_resource_len:
1508  *              Length of the metadata resource buffer, in bytes.
1509  *
1510  * @offset:     Offset of the dentry within the metadata resource.
1511  *
1512  * @dentry:     A `struct wim_dentry' that will be filled in by this function.
1513  *
1514  * Return 0 on success or nonzero on failure.  On failure, @dentry will have
1515  * been modified, but it will not be left with pointers to any allocated
1516  * buffers.  On success, the dentry->length field must be examined.  If zero,
1517  * this was a special "end of directory" dentry and not a real dentry.  If
1518  * nonzero, this was a real dentry.
1519  *
1520  * Possible errors include:
1521  *      WIMLIB_ERR_NOMEM
1522  *      WIMLIB_ERR_INVALID_DENTRY
1523  */
1524 int
1525 read_dentry(const u8 * restrict metadata_resource, u64 metadata_resource_len,
1526             u64 offset, struct wim_dentry * restrict dentry)
1527 {
1528
1529         u64 calculated_size;
1530         utf16lechar *file_name;
1531         utf16lechar *short_name;
1532         u16 short_name_nbytes;
1533         u16 file_name_nbytes;
1534         int ret;
1535         struct wim_inode *inode;
1536         const u8 *p = &metadata_resource[offset];
1537         const struct wim_dentry_on_disk *disk_dentry =
1538                         (const struct wim_dentry_on_disk*)p;
1539
1540         BUILD_BUG_ON(sizeof(struct wim_dentry_on_disk) != WIM_DENTRY_DISK_SIZE);
1541
1542         if ((uintptr_t)p & 7)
1543                 WARNING("WIM dentry is not 8-byte aligned");
1544
1545         dentry_common_init(dentry);
1546
1547         /* Before reading the whole dentry, we need to read just the length.
1548          * This is because a dentry of length 8 (that is, just the length field)
1549          * terminates the list of sibling directory entries. */
1550         if (offset + sizeof(u64) > metadata_resource_len ||
1551             offset + sizeof(u64) < offset)
1552         {
1553                 ERROR("Directory entry starting at %"PRIu64" ends past the "
1554                       "end of the metadata resource (size %"PRIu64")",
1555                       offset, metadata_resource_len);
1556                 return WIMLIB_ERR_INVALID_DENTRY;
1557         }
1558         dentry->length = le64_to_cpu(disk_dentry->length);
1559
1560         /* A zero length field (really a length of 8, since that's how big the
1561          * directory entry is...) indicates that this is the end of directory
1562          * dentry.  We do not read it into memory as an actual dentry, so just
1563          * return successfully in this case. */
1564         if (dentry->length == 8)
1565                 dentry->length = 0;
1566         if (dentry->length == 0)
1567                 return 0;
1568
1569         /* Now that we have the actual length provided in the on-disk structure,
1570          * again make sure it doesn't overflow the metadata resource buffer. */
1571         if (offset + dentry->length > metadata_resource_len ||
1572             offset + dentry->length < offset)
1573         {
1574                 ERROR("Directory entry at offset %"PRIu64" and with size "
1575                       "%"PRIu64" ends past the end of the metadata resource "
1576                       "(size %"PRIu64")",
1577                       offset, dentry->length, metadata_resource_len);
1578                 return WIMLIB_ERR_INVALID_DENTRY;
1579         }
1580
1581         /* Make sure the dentry length is at least as large as the number of
1582          * fixed-length fields */
1583         if (dentry->length < sizeof(struct wim_dentry_on_disk)) {
1584                 ERROR("Directory entry has invalid length of %"PRIu64" bytes",
1585                       dentry->length);
1586                 return WIMLIB_ERR_INVALID_DENTRY;
1587         }
1588
1589         /* Allocate a `struct wim_inode' for this `struct wim_dentry'. */
1590         inode = new_timeless_inode();
1591         if (!inode)
1592                 return WIMLIB_ERR_NOMEM;
1593
1594         /* Read more fields; some into the dentry, and some into the inode. */
1595
1596         inode->i_attributes = le32_to_cpu(disk_dentry->attributes);
1597         inode->i_security_id = le32_to_cpu(disk_dentry->security_id);
1598         dentry->subdir_offset = le64_to_cpu(disk_dentry->subdir_offset);
1599         dentry->d_unused_1 = le64_to_cpu(disk_dentry->unused_1);
1600         dentry->d_unused_2 = le64_to_cpu(disk_dentry->unused_2);
1601         inode->i_creation_time = le64_to_cpu(disk_dentry->creation_time);
1602         inode->i_last_access_time = le64_to_cpu(disk_dentry->last_access_time);
1603         inode->i_last_write_time = le64_to_cpu(disk_dentry->last_write_time);
1604         copy_hash(inode->i_hash, disk_dentry->unnamed_stream_hash);
1605
1606         /* I don't know what's going on here.  It seems like M$ screwed up the
1607          * reparse points, then put the fields in the same place and didn't
1608          * document it.  So we have some fields we read for reparse points, and
1609          * some fields in the same place for non-reparse-point.s */
1610         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1611                 inode->i_rp_unknown_1 = le32_to_cpu(disk_dentry->reparse.rp_unknown_1);
1612                 inode->i_reparse_tag = le32_to_cpu(disk_dentry->reparse.reparse_tag);
1613                 inode->i_rp_unknown_2 = le16_to_cpu(disk_dentry->reparse.rp_unknown_2);
1614                 inode->i_not_rpfixed = le16_to_cpu(disk_dentry->reparse.not_rpfixed);
1615                 /* Leave inode->i_ino at 0.  Note that this means the WIM file
1616                  * cannot archive hard-linked reparse points.  Such a thing
1617                  * doesn't really make sense anyway, although I believe it's
1618                  * theoretically possible to have them on NTFS. */
1619         } else {
1620                 inode->i_rp_unknown_1 = le32_to_cpu(disk_dentry->nonreparse.rp_unknown_1);
1621                 inode->i_ino = le64_to_cpu(disk_dentry->nonreparse.hard_link_group_id);
1622         }
1623
1624         inode->i_num_ads = le16_to_cpu(disk_dentry->num_alternate_data_streams);
1625
1626         short_name_nbytes = le16_to_cpu(disk_dentry->short_name_nbytes);
1627         file_name_nbytes = le16_to_cpu(disk_dentry->file_name_nbytes);
1628
1629         if ((short_name_nbytes & 1) | (file_name_nbytes & 1))
1630         {
1631                 ERROR("Dentry name is not valid UTF-16LE (odd number of bytes)!");
1632                 ret = WIMLIB_ERR_INVALID_DENTRY;
1633                 goto out_free_inode;
1634         }
1635
1636         /* We now know the length of the file name and short name.  Make sure
1637          * the length of the dentry is large enough to actually hold them.
1638          *
1639          * The calculated length here is unaligned to allow for the possibility
1640          * that the dentry->length names an unaligned length, although this
1641          * would be unexpected. */
1642         calculated_size = _dentry_correct_length_unaligned(file_name_nbytes,
1643                                                            short_name_nbytes);
1644
1645         if (dentry->length < calculated_size) {
1646                 ERROR("Unexpected end of directory entry! (Expected "
1647                       "at least %"PRIu64" bytes, got %"PRIu64" bytes.)",
1648                       calculated_size, dentry->length);
1649                 ret = WIMLIB_ERR_INVALID_DENTRY;
1650                 goto out_free_inode;
1651         }
1652
1653         p += sizeof(struct wim_dentry_on_disk);
1654
1655         /* Read the filename if present.  Note: if the filename is empty, there
1656          * is no null terminator following it. */
1657         if (file_name_nbytes) {
1658                 file_name = MALLOC(file_name_nbytes + 2);
1659                 if (!file_name) {
1660                         ERROR("Failed to allocate %d bytes for dentry file name",
1661                               file_name_nbytes + 2);
1662                         ret = WIMLIB_ERR_NOMEM;
1663                         goto out_free_inode;
1664                 }
1665                 memcpy(file_name, p, file_name_nbytes);
1666                 p += file_name_nbytes + 2;
1667                 file_name[file_name_nbytes / 2] = cpu_to_le16(0);
1668                 replace_forbidden_characters(file_name);
1669         } else {
1670                 file_name = NULL;
1671         }
1672
1673
1674         /* Read the short filename if present.  Note: if there is no short
1675          * filename, there is no null terminator following it. */
1676         if (short_name_nbytes) {
1677                 short_name = MALLOC(short_name_nbytes + 2);
1678                 if (!short_name) {
1679                         ERROR("Failed to allocate %d bytes for dentry short name",
1680                               short_name_nbytes + 2);
1681                         ret = WIMLIB_ERR_NOMEM;
1682                         goto out_free_file_name;
1683                 }
1684                 memcpy(short_name, p, short_name_nbytes);
1685                 p += short_name_nbytes + 2;
1686                 short_name[short_name_nbytes / 2] = cpu_to_le16(0);
1687                 replace_forbidden_characters(short_name);
1688         } else {
1689                 short_name = NULL;
1690         }
1691
1692         /* Align the dentry length */
1693         dentry->length = (dentry->length + 7) & ~7;
1694
1695         /*
1696          * Read the alternate data streams, if present.  dentry->num_ads tells
1697          * us how many they are, and they will directly follow the dentry
1698          * on-disk.
1699          *
1700          * Note that each alternate data stream entry begins on an 8-byte
1701          * aligned boundary, and the alternate data stream entries seem to NOT
1702          * be included in the dentry->length field for some reason.
1703          */
1704         if (inode->i_num_ads != 0) {
1705                 ret = WIMLIB_ERR_INVALID_DENTRY;
1706                 if (offset + dentry->length > metadata_resource_len ||
1707                     (ret = read_ads_entries(&metadata_resource[offset + dentry->length],
1708                                             inode,
1709                                             metadata_resource_len - offset - dentry->length)))
1710                 {
1711                         ERROR("Failed to read alternate data stream "
1712                               "entries of WIM dentry \"%"WS"\"", file_name);
1713                         goto out_free_short_name;
1714                 }
1715         }
1716         /* We've read all the data for this dentry.  Set the names and their
1717          * lengths, and we've done. */
1718         dentry->d_inode           = inode;
1719         dentry->file_name         = file_name;
1720         dentry->short_name        = short_name;
1721         dentry->file_name_nbytes  = file_name_nbytes;
1722         dentry->short_name_nbytes = short_name_nbytes;
1723         ret = 0;
1724         goto out;
1725 out_free_short_name:
1726         FREE(short_name);
1727 out_free_file_name:
1728         FREE(file_name);
1729 out_free_inode:
1730         free_inode(inode);
1731 out:
1732         return ret;
1733 }
1734
1735 /* Reads the children of a dentry, and all their children, ..., etc. from the
1736  * metadata resource and into the dentry tree.
1737  *
1738  * @metadata_resource:  An array that contains the uncompressed metadata
1739  *                      resource for the WIM file.
1740  *
1741  * @metadata_resource_len:  The length of the uncompressed metadata resource, in
1742  *                          bytes.
1743  *
1744  * @dentry:     A pointer to a `struct wim_dentry' that is the root of the directory
1745  *              tree and has already been read from the metadata resource.  It
1746  *              does not need to be the real root because this procedure is
1747  *              called recursively.
1748  *
1749  * Returns zero on success; nonzero on failure.
1750  */
1751 int
1752 read_dentry_tree(const u8 metadata_resource[], u64 metadata_resource_len,
1753                  struct wim_dentry *dentry)
1754 {
1755         u64 cur_offset = dentry->subdir_offset;
1756         struct wim_dentry *child;
1757         struct wim_dentry cur_child;
1758         int ret;
1759
1760         /*
1761          * If @dentry has no child dentries, nothing more needs to be done for
1762          * this branch.  This is the case for regular files, symbolic links, and
1763          * *possibly* empty directories (although an empty directory may also
1764          * have one child dentry that is the special end-of-directory dentry)
1765          */
1766         if (cur_offset == 0)
1767                 return 0;
1768
1769         /* Find and read all the children of @dentry. */
1770         for (;;) {
1771
1772                 /* Read next child of @dentry into @cur_child. */
1773                 ret = read_dentry(metadata_resource, metadata_resource_len,
1774                                   cur_offset, &cur_child);
1775                 if (ret)
1776                         break;
1777
1778                 /* Check for end of directory. */
1779                 if (cur_child.length == 0)
1780                         break;
1781
1782                 /* Not end of directory.  Allocate this child permanently and
1783                  * link it to the parent and previous child. */
1784                 child = memdup(&cur_child, sizeof(struct wim_dentry));
1785                 if (!child) {
1786                         ERROR("Failed to allocate new dentry!");
1787                         ret = WIMLIB_ERR_NOMEM;
1788                         break;
1789                 }
1790
1791                 /* Advance to the offset of the next child.  Note: We need to
1792                  * advance by the TOTAL length of the dentry, not by the length
1793                  * cur_child.length, which although it does take into account
1794                  * the padding, it DOES NOT take into account alternate stream
1795                  * entries. */
1796                 cur_offset += dentry_total_length(child);
1797
1798                 if (dentry_add_child(dentry, child)) {
1799                         WARNING("Ignoring duplicate dentry \"%"WS"\"",
1800                                 child->file_name);
1801                         WARNING("(In directory \"%"TS"\")", dentry_full_path(dentry));
1802                         free_dentry(child);
1803                 } else {
1804                         inode_add_dentry(child, child->d_inode);
1805                         /* If there are children of this child, call this
1806                          * procedure recursively. */
1807                         if (child->subdir_offset != 0) {
1808                                 if (dentry_is_directory(child)) {
1809                                         ret = read_dentry_tree(metadata_resource,
1810                                                                metadata_resource_len,
1811                                                                child);
1812                                         if (ret)
1813                                                 break;
1814                                 } else {
1815                                         WARNING("Ignoring children of non-directory \"%"TS"\"",
1816                                                 dentry_full_path(child));
1817                                 }
1818                         }
1819
1820                 }
1821         }
1822         return ret;
1823 }
1824
1825 /*
1826  * Writes a WIM dentry to an output buffer.
1827  *
1828  * @dentry:  The dentry structure.
1829  * @p:       The memory location to write the data to.
1830  *
1831  * Returns the pointer to the byte after the last byte we wrote as part of the
1832  * dentry, including any alternate data stream entries.
1833  */
1834 static u8 *
1835 write_dentry(const struct wim_dentry * restrict dentry, u8 * restrict p)
1836 {
1837         const struct wim_inode *inode;
1838         struct wim_dentry_on_disk *disk_dentry;
1839         const u8 *orig_p;
1840         const u8 *hash;
1841
1842         wimlib_assert(((uintptr_t)p & 7) == 0); /* 8 byte aligned */
1843         orig_p = p;
1844
1845         inode = dentry->d_inode;
1846         disk_dentry = (struct wim_dentry_on_disk*)p;
1847
1848         disk_dentry->attributes = cpu_to_le32(inode->i_attributes);
1849         disk_dentry->security_id = cpu_to_le32(inode->i_security_id);
1850         disk_dentry->subdir_offset = cpu_to_le64(dentry->subdir_offset);
1851         disk_dentry->unused_1 = cpu_to_le64(dentry->d_unused_1);
1852         disk_dentry->unused_2 = cpu_to_le64(dentry->d_unused_2);
1853         disk_dentry->creation_time = cpu_to_le64(inode->i_creation_time);
1854         disk_dentry->last_access_time = cpu_to_le64(inode->i_last_access_time);
1855         disk_dentry->last_write_time = cpu_to_le64(inode->i_last_write_time);
1856         hash = inode_stream_hash(inode, 0);
1857         copy_hash(disk_dentry->unnamed_stream_hash, hash);
1858         if (inode->i_attributes & FILE_ATTRIBUTE_REPARSE_POINT) {
1859                 disk_dentry->reparse.rp_unknown_1 = cpu_to_le32(inode->i_rp_unknown_1);
1860                 disk_dentry->reparse.reparse_tag = cpu_to_le32(inode->i_reparse_tag);
1861                 disk_dentry->reparse.rp_unknown_2 = cpu_to_le16(inode->i_rp_unknown_2);
1862                 disk_dentry->reparse.not_rpfixed = cpu_to_le16(inode->i_not_rpfixed);
1863         } else {
1864                 disk_dentry->nonreparse.rp_unknown_1 = cpu_to_le32(inode->i_rp_unknown_1);
1865                 disk_dentry->nonreparse.hard_link_group_id =
1866                         cpu_to_le64((inode->i_nlink == 1) ? 0 : inode->i_ino);
1867         }
1868         disk_dentry->num_alternate_data_streams = cpu_to_le16(inode->i_num_ads);
1869         disk_dentry->short_name_nbytes = cpu_to_le16(dentry->short_name_nbytes);
1870         disk_dentry->file_name_nbytes = cpu_to_le16(dentry->file_name_nbytes);
1871         p += sizeof(struct wim_dentry_on_disk);
1872
1873         if (dentry_has_long_name(dentry))
1874                 p = mempcpy(p, dentry->file_name, dentry->file_name_nbytes + 2);
1875
1876         if (dentry_has_short_name(dentry))
1877                 p = mempcpy(p, dentry->short_name, dentry->short_name_nbytes + 2);
1878
1879         /* Align to 8-byte boundary */
1880         while ((uintptr_t)p & 7)
1881                 *p++ = 0;
1882
1883         /* We calculate the correct length of the dentry ourselves because the
1884          * dentry->length field may been set to an unexpected value from when we
1885          * read the dentry in (for example, there may have been unknown data
1886          * appended to the end of the dentry...).  Furthermore, the dentry may
1887          * have been renamed, thus changing its needed length. */
1888         disk_dentry->length = cpu_to_le64(p - orig_p);
1889
1890         /* Write the alternate data streams entries, if any. */
1891         for (u16 i = 0; i < inode->i_num_ads; i++) {
1892                 const struct wim_ads_entry *ads_entry =
1893                                 &inode->i_ads_entries[i];
1894                 struct wim_ads_entry_on_disk *disk_ads_entry =
1895                                 (struct wim_ads_entry_on_disk*)p;
1896                 orig_p = p;
1897
1898                 disk_ads_entry->reserved = cpu_to_le64(ads_entry->reserved);
1899
1900                 hash = inode_stream_hash(inode, i + 1);
1901                 copy_hash(disk_ads_entry->hash, hash);
1902                 disk_ads_entry->stream_name_nbytes = cpu_to_le16(ads_entry->stream_name_nbytes);
1903                 p += sizeof(struct wim_ads_entry_on_disk);
1904                 if (ads_entry->stream_name_nbytes) {
1905                         p = mempcpy(p, ads_entry->stream_name,
1906                                     ads_entry->stream_name_nbytes + 2);
1907                 }
1908                 /* Align to 8-byte boundary */
1909                 while ((uintptr_t)p & 7)
1910                         *p++ = 0;
1911                 disk_ads_entry->length = cpu_to_le64(p - orig_p);
1912         }
1913         return p;
1914 }
1915
1916 static int
1917 write_dentry_cb(struct wim_dentry *dentry, void *_p)
1918 {
1919         u8 **p = _p;
1920         *p = write_dentry(dentry, *p);
1921         return 0;
1922 }
1923
1924 static u8 *
1925 write_dentry_tree_recursive(const struct wim_dentry *parent, u8 *p);
1926
1927 static int
1928 write_dentry_tree_recursive_cb(struct wim_dentry *dentry, void *_p)
1929 {
1930         u8 **p = _p;
1931         *p = write_dentry_tree_recursive(dentry, *p);
1932         return 0;
1933 }
1934
1935 /* Recursive function that writes a dentry tree rooted at @parent, not including
1936  * @parent itself, which has already been written. */
1937 static u8 *
1938 write_dentry_tree_recursive(const struct wim_dentry *parent, u8 *p)
1939 {
1940         /* Nothing to do if this dentry has no children. */
1941         if (parent->subdir_offset == 0)
1942                 return p;
1943
1944         /* Write child dentries and end-of-directory entry.
1945          *
1946          * Note: we need to write all of this dentry's children before
1947          * recursively writing the directory trees rooted at each of the child
1948          * dentries, since the on-disk dentries for a dentry's children are
1949          * always located at consecutive positions in the metadata resource! */
1950         for_dentry_child(parent, write_dentry_cb, &p);
1951
1952         /* write end of directory entry */
1953         *(le64*)p = cpu_to_le64(0);
1954         p += 8;
1955
1956         /* Recurse on children. */
1957         for_dentry_child(parent, write_dentry_tree_recursive_cb, &p);
1958         return p;
1959 }
1960
1961 /* Writes a directory tree to the metadata resource.
1962  *
1963  * @root:       Root of the dentry tree.
1964  * @p:          Pointer to a buffer with enough space for the dentry tree.
1965  *
1966  * Returns pointer to the byte after the last byte we wrote.
1967  */
1968 u8 *
1969 write_dentry_tree(const struct wim_dentry *root, u8 *p)
1970 {
1971         DEBUG("Writing dentry tree.");
1972         wimlib_assert(dentry_is_root(root));
1973
1974         /* If we're the root dentry, we have no parent that already
1975          * wrote us, so we need to write ourselves. */
1976         p = write_dentry(root, p);
1977
1978         /* Write end of directory entry after the root dentry just to be safe;
1979          * however the root dentry obviously cannot have any siblings. */
1980         *(le64*)p = cpu_to_le64(0);
1981         p += 8;
1982
1983         /* Recursively write the rest of the dentry tree. */
1984         return write_dentry_tree_recursive(root, p);
1985 }