01f7383571c5f00899b6c7814f9f0e8323d398df
[wimlib] / src / lookup_table.c
1 /*
2  * lookup_table.c
3  *
4  * Lookup table, implemented as a hash table, that maps SHA1 message digests to
5  * data streams; plus code to read and write the corresponding on-disk data.
6  */
7
8 /*
9  * Copyright (C) 2012, 2013 Eric Biggers
10  *
11  * This file is part of wimlib, a library for working with WIM files.
12  *
13  * wimlib is free software; you can redistribute it and/or modify it under the
14  * terms of the GNU General Public License as published by the Free
15  * Software Foundation; either version 3 of the License, or (at your option)
16  * any later version.
17  *
18  * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
19  * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
20  * A PARTICULAR PURPOSE. See the GNU General Public License for more
21  * details.
22  *
23  * You should have received a copy of the GNU General Public License
24  * along with wimlib; if not, see http://www.gnu.org/licenses/.
25  */
26
27 #ifdef HAVE_CONFIG_H
28 #  include "config.h"
29 #endif
30
31 #include "wimlib/assert.h"
32 #include "wimlib/endianness.h"
33 #include "wimlib/error.h"
34 #include "wimlib/lookup_table.h"
35 #include "wimlib/metadata.h"
36 #include "wimlib/ntfs_3g.h"
37 #include "wimlib/resource.h"
38 #include "wimlib/util.h"
39 #include "wimlib/write.h"
40
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h> /* for unlink()  */
44
45 /* WIM lookup table:
46  *
47  * This is a logical mapping from SHA1 message digests to the data streams
48  * contained in a WIM.
49  *
50  * Here it is implemented as a hash table.
51  *
52  * Note: Everything will break horribly if there is a SHA1 collision.
53  */
54 struct wim_lookup_table {
55         struct hlist_head *array;
56         size_t num_entries;
57         size_t capacity;
58 };
59
60 struct wim_lookup_table *
61 new_lookup_table(size_t capacity)
62 {
63         struct wim_lookup_table *table;
64         struct hlist_head *array;
65
66         table = MALLOC(sizeof(struct wim_lookup_table));
67         if (table == NULL)
68                 goto oom;
69
70         array = CALLOC(capacity, sizeof(array[0]));
71         if (array == NULL) {
72                 FREE(table);
73                 goto oom;
74         }
75
76         table->num_entries = 0;
77         table->capacity = capacity;
78         table->array = array;
79         return table;
80
81 oom:
82         ERROR("Failed to allocate memory for lookup table "
83               "with capacity %zu", capacity);
84         return NULL;
85 }
86
87 static int
88 do_free_lookup_table_entry(struct wim_lookup_table_entry *entry, void *ignore)
89 {
90         free_lookup_table_entry(entry);
91         return 0;
92 }
93
94 void
95 free_lookup_table(struct wim_lookup_table *table)
96 {
97         DEBUG("Freeing lookup table.");
98         if (table == NULL)
99                 return;
100
101         if (table->array) {
102                 for_lookup_table_entry(table,
103                                        do_free_lookup_table_entry,
104                                        NULL);
105                 FREE(table->array);
106         }
107         FREE(table);
108 }
109
110 struct wim_lookup_table_entry *
111 new_lookup_table_entry(void)
112 {
113         struct wim_lookup_table_entry *lte;
114
115         lte = CALLOC(1, sizeof(struct wim_lookup_table_entry));
116         if (lte == NULL)
117                 return NULL;
118
119         lte->refcnt = 1;
120
121         /* lte->resource_location = RESOURCE_NONEXISTENT  */
122         BUILD_BUG_ON(RESOURCE_NONEXISTENT != 0);
123
124         return lte;
125 }
126
127 struct wim_lookup_table_entry *
128 clone_lookup_table_entry(const struct wim_lookup_table_entry *old)
129 {
130         struct wim_lookup_table_entry *new;
131
132         new = memdup(old, sizeof(struct wim_lookup_table_entry));
133         if (new == NULL)
134                 return NULL;
135
136         new->extracted_file = NULL;
137         switch (new->resource_location) {
138         case RESOURCE_IN_WIM:
139                 list_add(&new->rspec_node, &new->rspec->stream_list);
140                 break;
141
142         case RESOURCE_IN_FILE_ON_DISK:
143 #ifdef __WIN32__
144         case RESOURCE_WIN32_ENCRYPTED:
145 #endif
146 #ifdef WITH_FUSE
147         case RESOURCE_IN_STAGING_FILE:
148                 BUILD_BUG_ON((void*)&old->file_on_disk !=
149                              (void*)&old->staging_file_name);
150 #endif
151                 new->file_on_disk = TSTRDUP(old->file_on_disk);
152                 if (new->file_on_disk == NULL)
153                         goto out_free;
154                 break;
155         case RESOURCE_IN_ATTACHED_BUFFER:
156                 new->attached_buffer = memdup(old->attached_buffer, old->size);
157                 if (new->attached_buffer == NULL)
158                         goto out_free;
159                 break;
160 #ifdef WITH_NTFS_3G
161         case RESOURCE_IN_NTFS_VOLUME:
162                 if (old->ntfs_loc) {
163                         struct ntfs_location *loc;
164                         loc = memdup(old->ntfs_loc, sizeof(struct ntfs_location));
165                         if (loc == NULL)
166                                 goto out_free;
167                         loc->path = NULL;
168                         loc->stream_name = NULL;
169                         new->ntfs_loc = loc;
170                         loc->path = STRDUP(old->ntfs_loc->path);
171                         if (loc->path == NULL)
172                                 goto out_free;
173                         if (loc->stream_name_nchars != 0) {
174                                 loc->stream_name = memdup(old->ntfs_loc->stream_name,
175                                                           loc->stream_name_nchars * 2);
176                                 if (loc->stream_name == NULL)
177                                         goto out_free;
178                         }
179                 }
180                 break;
181 #endif
182         default:
183                 break;
184         }
185         return new;
186
187 out_free:
188         free_lookup_table_entry(new);
189         return NULL;
190 }
191
192 void
193 lte_put_resource(struct wim_lookup_table_entry *lte)
194 {
195         switch (lte->resource_location) {
196         case RESOURCE_IN_WIM:
197                 list_del(&lte->rspec_node);
198                 if (list_empty(&lte->rspec->stream_list))
199                         FREE(lte->rspec);
200                 break;
201         case RESOURCE_IN_FILE_ON_DISK:
202 #ifdef __WIN32__
203         case RESOURCE_WIN32_ENCRYPTED:
204 #endif
205 #ifdef WITH_FUSE
206         case RESOURCE_IN_STAGING_FILE:
207                 BUILD_BUG_ON((void*)&lte->file_on_disk !=
208                              (void*)&lte->staging_file_name);
209 #endif
210         case RESOURCE_IN_ATTACHED_BUFFER:
211                 BUILD_BUG_ON((void*)&lte->file_on_disk !=
212                              (void*)&lte->attached_buffer);
213                 FREE(lte->file_on_disk);
214                 break;
215 #ifdef WITH_NTFS_3G
216         case RESOURCE_IN_NTFS_VOLUME:
217                 if (lte->ntfs_loc) {
218                         FREE(lte->ntfs_loc->path);
219                         FREE(lte->ntfs_loc->stream_name);
220                         FREE(lte->ntfs_loc);
221                 }
222                 break;
223 #endif
224         default:
225                 break;
226         }
227 }
228
229 void
230 free_lookup_table_entry(struct wim_lookup_table_entry *lte)
231 {
232         if (lte) {
233                 lte_put_resource(lte);
234                 FREE(lte);
235         }
236 }
237
238 /* Should this stream be retained even if it has no references?  */
239 static bool
240 should_retain_lte(const struct wim_lookup_table_entry *lte)
241 {
242         return lte->resource_location == RESOURCE_IN_WIM;
243 }
244
245 static void
246 finalize_lte(struct wim_lookup_table_entry *lte)
247 {
248         if (!should_retain_lte(lte))
249                 free_lookup_table_entry(lte);
250 }
251
252 /*
253  * Decrements the reference count for the lookup table entry @lte, which must be
254  * inserted in the stream lookup table @table.
255  *
256  * If the reference count reaches 0, this may cause @lte to be destroyed.
257  * However, we may retain entries with 0 reference count.  This does not affect
258  * correctness, but it prevents the entries for valid streams in a WIM archive,
259  * which will continue to be present after appending to the file, from being
260  * lost merely because we dropped all references to them.
261  */
262 void
263 lte_decrement_refcnt(struct wim_lookup_table_entry *lte,
264                      struct wim_lookup_table *table)
265 {
266         wimlib_assert(lte->refcnt != 0);
267
268         if (--lte->refcnt == 0) {
269                 if (lte->unhashed) {
270                         list_del(&lte->unhashed_list);
271                 #ifdef WITH_FUSE
272                         /* If the stream has been extracted to a staging file
273                          * for a FUSE mount, unlink the staging file.  (Note
274                          * that there still may be open file descriptors to it.)
275                          * */
276                         if (lte->resource_location == RESOURCE_IN_STAGING_FILE)
277                                 unlink(lte->staging_file_name);
278                 #endif
279                 } else {
280                         if (!should_retain_lte(lte))
281                                 lookup_table_unlink(table, lte);
282                 }
283
284                 /* If FUSE mounts are enabled, we don't actually free the entry
285                  * until the last file descriptor has been closed by
286                  * lte_decrement_num_opened_fds().  */
287 #ifdef WITH_FUSE
288                 if (lte->num_opened_fds == 0)
289 #endif
290                         finalize_lte(lte);
291         }
292 }
293
294 #ifdef WITH_FUSE
295 void
296 lte_decrement_num_opened_fds(struct wim_lookup_table_entry *lte)
297 {
298         wimlib_assert(lte->num_opened_fds != 0);
299
300         if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
301                 finalize_lte(lte);
302 }
303 #endif
304
305 static void
306 lookup_table_insert_raw(struct wim_lookup_table *table,
307                         struct wim_lookup_table_entry *lte)
308 {
309         size_t i = lte->hash_short % table->capacity;
310
311         hlist_add_head(&lte->hash_list, &table->array[i]);
312 }
313
314 static void
315 enlarge_lookup_table(struct wim_lookup_table *table)
316 {
317         size_t old_capacity, new_capacity;
318         struct hlist_head *old_array, *new_array;
319         struct wim_lookup_table_entry *lte;
320         struct hlist_node *cur, *tmp;
321         size_t i;
322
323         old_capacity = table->capacity;
324         new_capacity = old_capacity * 2;
325         new_array = CALLOC(new_capacity, sizeof(struct hlist_head));
326         if (new_array == NULL)
327                 return;
328         old_array = table->array;
329         table->array = new_array;
330         table->capacity = new_capacity;
331
332         for (i = 0; i < old_capacity; i++) {
333                 hlist_for_each_entry_safe(lte, cur, tmp, &old_array[i], hash_list) {
334                         hlist_del(&lte->hash_list);
335                         lookup_table_insert_raw(table, lte);
336                 }
337         }
338         FREE(old_array);
339 }
340
341 /* Inserts an entry into the lookup table.  */
342 void
343 lookup_table_insert(struct wim_lookup_table *table,
344                     struct wim_lookup_table_entry *lte)
345 {
346         lookup_table_insert_raw(table, lte);
347         if (++table->num_entries > table->capacity)
348                 enlarge_lookup_table(table);
349 }
350
351 /* Unlinks a lookup table entry from the table; does not free it.  */
352 void
353 lookup_table_unlink(struct wim_lookup_table *table,
354                     struct wim_lookup_table_entry *lte)
355 {
356         wimlib_assert(!lte->unhashed);
357         wimlib_assert(table->num_entries != 0);
358
359         hlist_del(&lte->hash_list);
360         table->num_entries--;
361 }
362
363 /* Given a SHA1 message digest, return the corresponding entry in the WIM's
364  * lookup table, or NULL if there is none.  */
365 struct wim_lookup_table_entry *
366 lookup_stream(const struct wim_lookup_table *table, const u8 hash[])
367 {
368         size_t i;
369         struct wim_lookup_table_entry *lte;
370         struct hlist_node *pos;
371
372         i = *(size_t*)hash % table->capacity;
373         hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
374                 if (hashes_equal(hash, lte->hash))
375                         return lte;
376         return NULL;
377 }
378
379 /* Calls a function on all the entries in the WIM lookup table.  Stop early and
380  * return nonzero if any call to the function returns nonzero. */
381 int
382 for_lookup_table_entry(struct wim_lookup_table *table,
383                        int (*visitor)(struct wim_lookup_table_entry *, void *),
384                        void *arg)
385 {
386         struct wim_lookup_table_entry *lte;
387         struct hlist_node *pos, *tmp;
388         int ret;
389
390         for (size_t i = 0; i < table->capacity; i++) {
391                 hlist_for_each_entry_safe(lte, pos, tmp, &table->array[i],
392                                           hash_list)
393                 {
394                         ret = visitor(lte, arg);
395                         if (ret)
396                                 return ret;
397                 }
398         }
399         return 0;
400 }
401
402 /* qsort() callback that sorts streams (represented by `struct
403  * wim_lookup_table_entry's) into an order optimized for reading.
404  *
405  * Sorting is done primarily by resource location, then secondarily by a
406  * per-resource location order.  For example, resources in WIM files are sorted
407  * primarily by part number, then secondarily by offset, as to implement optimal
408  * reading of either a standalone or split WIM.  */
409 static int
410 cmp_streams_by_sequential_order(const void *p1, const void *p2)
411 {
412         const struct wim_lookup_table_entry *lte1, *lte2;
413         int v;
414         WIMStruct *wim1, *wim2;
415
416         lte1 = *(const struct wim_lookup_table_entry**)p1;
417         lte2 = *(const struct wim_lookup_table_entry**)p2;
418
419         v = (int)lte1->resource_location - (int)lte2->resource_location;
420
421         /* Different resource locations?  */
422         if (v)
423                 return v;
424
425         switch (lte1->resource_location) {
426         case RESOURCE_IN_WIM:
427                 wim1 = lte1->rspec->wim;
428                 wim2 = lte2->rspec->wim;
429
430                 /* Different (possibly split) WIMs?  */
431                 if (wim1 != wim2) {
432                         v = memcmp(wim1->hdr.guid, wim2->hdr.guid, WIM_GID_LEN);
433                         if (v)
434                                 return v;
435                 }
436
437                 /* Different part numbers in the same WIM?  */
438                 v = (int)wim1->hdr.part_number - (int)wim2->hdr.part_number;
439                 if (v)
440                         return v;
441
442                 if (lte1->rspec->offset_in_wim != lte2->rspec->offset_in_wim)
443                         return cmp_u64(lte1->rspec->offset_in_wim,
444                                        lte2->rspec->offset_in_wim);
445
446                 return cmp_u64(lte1->offset_in_res, lte2->offset_in_res);
447
448         case RESOURCE_IN_FILE_ON_DISK:
449 #ifdef WITH_FUSE
450         case RESOURCE_IN_STAGING_FILE:
451 #endif
452 #ifdef __WIN32__
453         case RESOURCE_WIN32_ENCRYPTED:
454 #endif
455                 /* Compare files by path: just a heuristic that will place files
456                  * in the same directory next to each other.  */
457                 return tstrcmp(lte1->file_on_disk, lte2->file_on_disk);
458 #ifdef WITH_NTFS_3G
459         case RESOURCE_IN_NTFS_VOLUME:
460                 return tstrcmp(lte1->ntfs_loc->path, lte2->ntfs_loc->path);
461 #endif
462         default:
463                 /* No additional sorting order defined for this resource
464                  * location (e.g. RESOURCE_IN_ATTACHED_BUFFER); simply compare
465                  * everything equal to each other.  */
466                 return 0;
467         }
468 }
469
470 int
471 sort_stream_list(struct list_head *stream_list,
472                  size_t list_head_offset,
473                  int (*compar)(const void *, const void*))
474 {
475         struct list_head *cur;
476         struct wim_lookup_table_entry **array;
477         size_t i;
478         size_t array_size;
479         size_t num_streams = 0;
480
481         list_for_each(cur, stream_list)
482                 num_streams++;
483
484         if (num_streams <= 1)
485                 return 0;
486
487         array_size = num_streams * sizeof(array[0]);
488         array = MALLOC(array_size);
489         if (array == NULL)
490                 return WIMLIB_ERR_NOMEM;
491
492         cur = stream_list->next;
493         for (i = 0; i < num_streams; i++) {
494                 array[i] = (struct wim_lookup_table_entry*)((u8*)cur -
495                                                             list_head_offset);
496                 cur = cur->next;
497         }
498
499         qsort(array, num_streams, sizeof(array[0]), compar);
500
501         INIT_LIST_HEAD(stream_list);
502         for (i = 0; i < num_streams; i++) {
503                 list_add_tail((struct list_head*)
504                                ((u8*)array[i] + list_head_offset),
505                               stream_list);
506         }
507         FREE(array);
508         return 0;
509 }
510
511 /* Sort the specified list of streams in an order optimized for reading.  */
512 int
513 sort_stream_list_by_sequential_order(struct list_head *stream_list,
514                                      size_t list_head_offset)
515 {
516         return sort_stream_list(stream_list, list_head_offset,
517                                 cmp_streams_by_sequential_order);
518 }
519
520
521 static int
522 add_lte_to_array(struct wim_lookup_table_entry *lte,
523                  void *_pp)
524 {
525         struct wim_lookup_table_entry ***pp = _pp;
526         *(*pp)++ = lte;
527         return 0;
528 }
529
530 /* Iterate through the lookup table entries, but first sort them by stream
531  * offset in the WIM.  Caution: this is intended to be used when the stream
532  * offset field has actually been set. */
533 int
534 for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
535                                   int (*visitor)(struct wim_lookup_table_entry *,
536                                                  void *),
537                                   void *arg)
538 {
539         struct wim_lookup_table_entry **lte_array, **p;
540         size_t num_streams = table->num_entries;
541         int ret;
542
543         lte_array = MALLOC(num_streams * sizeof(lte_array[0]));
544         if (!lte_array)
545                 return WIMLIB_ERR_NOMEM;
546         p = lte_array;
547         for_lookup_table_entry(table, add_lte_to_array, &p);
548
549         wimlib_assert(p == lte_array + num_streams);
550
551         qsort(lte_array, num_streams, sizeof(lte_array[0]),
552               cmp_streams_by_sequential_order);
553         ret = 0;
554         for (size_t i = 0; i < num_streams; i++) {
555                 ret = visitor(lte_array[i], arg);
556                 if (ret)
557                         break;
558         }
559         FREE(lte_array);
560         return ret;
561 }
562
563 /* On-disk format of a WIM lookup table entry (stream entry). */
564 struct wim_lookup_table_entry_disk {
565         /* Size, offset, and flags of the stream.  */
566         struct wim_reshdr_disk reshdr;
567
568         /* Which part of the split WIM this stream is in; indexed from 1. */
569         le16 part_number;
570
571         /* Reference count of this stream over all WIM images. */
572         le32 refcnt;
573
574         /* SHA1 message digest of the uncompressed data of this stream, or
575          * optionally all zeroes if this stream is of zero length. */
576         u8 hash[SHA1_HASH_SIZE];
577 } _packed_attribute;
578
579 #define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
580
581 static int
582 cmp_streams_by_offset_in_res(const void *p1, const void *p2)
583 {
584         const struct wim_lookup_table_entry *lte1, *lte2;
585
586         lte1 = *(const struct wim_lookup_table_entry**)p1;
587         lte2 = *(const struct wim_lookup_table_entry**)p2;
588
589         return cmp_u64(lte1->offset_in_res, lte2->offset_in_res);
590 }
591
592 /* Validate the size and location of a WIM resource.  */
593 static int
594 validate_resource(struct wim_resource_spec *rspec)
595 {
596         struct wim_lookup_table_entry *lte;
597         bool out_of_order;
598         u64 expected_next_offset;
599         int ret;
600
601         /* Verify that the resource itself has a valid offset and size.  */
602         if (rspec->offset_in_wim + rspec->size_in_wim < rspec->size_in_wim)
603                 goto invalid_due_to_overflow;
604
605         /* Verify that each stream in the resource has a valid offset and size.
606          */
607         expected_next_offset = 0;
608         out_of_order = false;
609         list_for_each_entry(lte, &rspec->stream_list, rspec_node) {
610                 if (lte->offset_in_res + lte->size < lte->size ||
611                     lte->offset_in_res + lte->size > rspec->uncompressed_size)
612                         goto invalid_due_to_overflow;
613
614                 if (lte->offset_in_res >= expected_next_offset)
615                         expected_next_offset = lte->offset_in_res + lte->size;
616                 else
617                         out_of_order = true;
618         }
619
620         /* If the streams were not located at strictly increasing positions (not
621          * allowing for overlap), sort them.  Then make sure that none overlap.
622          */
623         if (out_of_order) {
624                 ret = sort_stream_list(&rspec->stream_list,
625                                        offsetof(struct wim_lookup_table_entry,
626                                                 rspec_node),
627                                        cmp_streams_by_offset_in_res);
628                 if (ret)
629                         return ret;
630
631                 expected_next_offset = 0;
632                 list_for_each_entry(lte, &rspec->stream_list, rspec_node) {
633                         if (lte->offset_in_res >= expected_next_offset)
634                                 expected_next_offset = lte->offset_in_res + lte->size;
635                         else
636                                 goto invalid_due_to_overlap;
637                 }
638         }
639
640         return 0;
641
642 invalid_due_to_overflow:
643         ERROR("Invalid resource entry (offset overflow)");
644         return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
645
646 invalid_due_to_overlap:
647         ERROR("Invalid resource entry (streams in packed resource overlap)");
648         return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
649 }
650
651 /* Validate the resource, or free it if unused.  */
652 static int
653 finish_resource(struct wim_resource_spec *rspec)
654 {
655         if (!list_empty(&rspec->stream_list)) {
656                 /* This resource contains at least one stream.  */
657                 return validate_resource(rspec);
658         } else {
659                 /* No streams are in this resource.  Get rid of it.  */
660                 FREE(rspec);
661                 return 0;
662         }
663 }
664
665 /*
666  * Reads the lookup table from a WIM file.  Usually, each entry specifies a
667  * stream that the WIM file contains, along with its location and SHA1 message
668  * digest.
669  *
670  * Saves lookup table entries for non-metadata streams in a hash table (set to
671  * wim->lookup_table), and saves the metadata entry for each image in a special
672  * per-image location (the wim->image_metadata array).
673  *
674  * This works for both version WIM_VERSION_DEFAULT (68864) and version
675  * WIM_VERSION_PACKED_STREAMS (3584) WIMs.
676  *
677  * Possible return values:
678  *      WIMLIB_ERR_SUCCESS (0)
679  *      WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY
680  *      WIMLIB_ERR_NOMEM
681  *
682  *      Or an error code caused by failure to read the lookup table from the WIM
683  *      file.
684  */
685 int
686 read_wim_lookup_table(WIMStruct *wim)
687 {
688         int ret;
689         size_t num_entries;
690         void *buf = NULL;
691         struct wim_lookup_table *table = NULL;
692         struct wim_lookup_table_entry *cur_entry = NULL;
693         struct wim_resource_spec *cur_rspec = NULL;
694         size_t num_duplicate_entries = 0;
695         size_t num_wrong_part_entries = 0;
696         u32 image_index = 0;
697
698         DEBUG("Reading lookup table.");
699
700         /* Sanity check: lookup table entries are 50 bytes each.  */
701         BUILD_BUG_ON(sizeof(struct wim_lookup_table_entry_disk) !=
702                      WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE);
703
704         /* Calculate the number of entries in the lookup table.  */
705         num_entries = wim->hdr.lookup_table_reshdr.uncompressed_size /
706                       sizeof(struct wim_lookup_table_entry_disk);
707
708         /* Read the lookup table into a buffer.  */
709         ret = wim_reshdr_to_data(&wim->hdr.lookup_table_reshdr, wim, &buf);
710         if (ret)
711                 goto out;
712
713         /* Allocate a hash table to map SHA1 message digests into stream
714          * specifications.  This is the in-memory "lookup table".  */
715         table = new_lookup_table(num_entries * 2 + 1);
716         if (!table)
717                 goto oom;
718
719         /* Allocate and initalize stream entries ('struct
720          * wim_lookup_table_entry's) from the raw lookup table buffer.  Each of
721          * these entries will point to a 'struct wim_resource_spec' that
722          * describes the underlying resource.  In WIMs with version number
723          * WIM_VERSION_PACKED_STREAMS, a resource may contain multiple streams.
724          */
725         for (size_t i = 0; i < num_entries; i++) {
726                 const struct wim_lookup_table_entry_disk *disk_entry =
727                         &((const struct wim_lookup_table_entry_disk*)buf)[i];
728                 struct wim_reshdr reshdr;
729                 u16 part_number;
730                 struct wim_lookup_table_entry *duplicate_entry;
731
732                 /* Get the resource header  */
733                 get_wim_reshdr(&disk_entry->reshdr, &reshdr);
734
735                 DEBUG("reshdr: size_in_wim=%"PRIu64", "
736                       "uncompressed_size=%"PRIu64", "
737                       "offset_in_wim=%"PRIu64", "
738                       "flags=0x%02x\n",
739                       reshdr.size_in_wim, reshdr.uncompressed_size,
740                       reshdr.offset_in_wim, reshdr.flags);
741
742                 /* Ignore PACKED_STREAMS flag if it isn't supposed to be used in
743                  * this WIM version  */
744                 if (wim->hdr.wim_version == WIM_VERSION_DEFAULT)
745                         reshdr.flags &= ~WIM_RESHDR_FLAG_PACKED_STREAMS;
746
747                 /* Allocate a 'struct wim_lookup_table_entry'  */
748                 cur_entry = new_lookup_table_entry();
749                 if (!cur_entry)
750                         goto oom;
751
752                 /* Get the part number, reference count, and hash.  */
753                 part_number = le16_to_cpu(disk_entry->part_number);
754                 cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
755                 copy_hash(cur_entry->hash, disk_entry->hash);
756
757                 /* Verify that the part number matches that of the underlying
758                  * WIM file.  */
759                 if (part_number != wim->hdr.part_number) {
760                         num_wrong_part_entries++;
761                         goto free_cur_entry_and_continue;
762                 }
763
764                 /* If resource is uncompressed, check for (unexpected) size
765                  * mismatch.  */
766                 if (!(reshdr.flags & (WIM_RESHDR_FLAG_PACKED_STREAMS |
767                                       WIM_RESHDR_FLAG_COMPRESSED))) {
768                         if (reshdr.uncompressed_size != reshdr.size_in_wim) {
769                                 /* So ... This is an uncompressed resource, but
770                                  * its uncompressed size is NOT the same as its
771                                  * "compressed" size (size_in_wim).  What to do
772                                  * with it?
773                                  *
774                                  * Based on a simple test, WIMGAPI seems to
775                                  * handle this as follows:
776                                  *
777                                  * if (size_in_wim > uncompressed_size) {
778                                  *      Ignore uncompressed_size; use
779                                  *      size_in_wim instead.
780                                  * } else {
781                                  *      Honor uncompressed_size, but treat the
782                                  *      part of the file data above size_in_wim
783                                  *      as all zeros.
784                                  * }
785                                  *
786                                  * So we will do the same.
787                                  */
788                                 if (reshdr.size_in_wim > reshdr.uncompressed_size)
789                                         reshdr.uncompressed_size = reshdr.size_in_wim;
790                         }
791                 }
792
793                 /*
794                  * Possibly start a new resource.
795                  *
796                  * We need to start a new resource if:
797                  *
798                  * - There is no previous resource (cur_rspec).
799                  *
800                  *   OR
801                  *
802                  * - The resource header did not have PACKED_STREAMS set, so it
803                  *   specifies a new, single-stream resource.
804                  *
805                  *   OR
806                  *
807                  * - The resource header had PACKED_STREAMS set, and it's a
808                  *   special entry that specifies the resource itself as opposed
809                  *   to a stream, and we already encountered one such entry in
810                  *   the current resource.  We will interpret this as the
811                  *   beginning of a new packed resource.  (However, note that
812                  *   wimlib does not currently allow create WIMs with multiple
813                  *   packed resources, as to remain compatible with WIMGAPI.)
814                  */
815                 if (likely(!cur_rspec) ||
816                     !(reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) ||
817                       (reshdr.uncompressed_size == WIM_PACK_MAGIC_NUMBER &&
818                        cur_rspec->size_in_wim != 0))
819                 {
820                         /* Finish previous resource (if existent)  */
821                         if (cur_rspec) {
822                                 ret = finish_resource(cur_rspec);
823                                 cur_rspec = NULL;
824                                 if (ret)
825                                         goto out;
826                         }
827
828                         /* Allocate the resource specification and initialize it
829                          * with values from the current stream entry.  */
830                         cur_rspec = MALLOC(sizeof(*cur_rspec));
831                         if (!cur_rspec)
832                                 goto oom;
833
834                         wim_res_hdr_to_spec(&reshdr, wim, cur_rspec);
835
836                         /* If this is a packed run, the current stream entry may
837                          * specify a stream within the resource, and not the
838                          * resource itself.  Zero possibly irrelevant data until
839                          * it is read for certain.  */
840                         if (reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
841                                 cur_rspec->size_in_wim = 0;
842                                 cur_rspec->uncompressed_size = 0;
843                                 cur_rspec->offset_in_wim = 0;
844                         }
845                 }
846
847                 /* Now cur_rspec != NULL.  */
848
849                 /* Checked for packed resource specification.  */
850                 if (unlikely((reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) &&
851                              reshdr.uncompressed_size == WIM_PACK_MAGIC_NUMBER))
852                 {
853                         /* Found the specification for the packed resource.
854                          * Transfer the values to the `struct
855                          * wim_resource_spec', and discard the current stream
856                          * since this lookup table entry did not, in fact,
857                          * correspond to a "stream".  */
858
859                         /* The uncompressed size of the packed resource is
860                          * actually stored in the header of the resource itself.
861                          * Read it, and also grab the chunk size and compression
862                          * type (which are not necessarily the defaults from the
863                          * WIM header).  */
864                         struct alt_chunk_table_header_disk hdr;
865
866                         ret = full_pread(&wim->in_fd, &hdr,
867                                          sizeof(hdr), reshdr.offset_in_wim);
868                         if (ret)
869                                 goto out;
870
871                         cur_rspec->uncompressed_size = le64_to_cpu(hdr.res_usize);
872                         cur_rspec->offset_in_wim = reshdr.offset_in_wim;
873                         cur_rspec->size_in_wim = reshdr.size_in_wim;
874                         cur_rspec->flags = reshdr.flags;
875
876                         /* Compression format numbers must be the same as in
877                          * WIMGAPI to be compatible here.  */
878                         BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_NONE != 0);
879                         BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_XPRESS != 1);
880                         BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_LZX != 2);
881                         BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_LZMS != 3);
882                         cur_rspec->compression_type = le32_to_cpu(hdr.compression_format);
883
884                         cur_rspec->chunk_size = le32_to_cpu(hdr.chunk_size);
885
886                         DEBUG("Full pack is %"PRIu64" compressed bytes "
887                               "at file offset %"PRIu64" (flags 0x%02x)",
888                               cur_rspec->size_in_wim,
889                               cur_rspec->offset_in_wim,
890                               cur_rspec->flags);
891                         goto free_cur_entry_and_continue;
892                 }
893
894                 /* Ignore entries with all zeroes in the hash field.  */
895                 if (is_zero_hash(cur_entry->hash))
896                         goto free_cur_entry_and_continue;
897
898                 if (reshdr.flags & WIM_RESHDR_FLAG_METADATA) {
899
900                         /* Lookup table entry for a metadata resource.  */
901
902                         /* Metadata entries with no references must be ignored.
903                          * See, for example, the WinPE WIMs from the WAIK v2.1.
904                          */
905                         if (cur_entry->refcnt == 0)
906                                 goto free_cur_entry_and_continue;
907
908                         if (cur_entry->refcnt != 1) {
909                                 /* We don't currently support this case due to
910                                  * the complications of multiple images sharing
911                                  * the same metadata resource or a metadata
912                                  * resource also being referenced by files.
913                                  */
914                                 ERROR("Found metadata resource with refcnt != 1");
915                                 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
916                                 goto out;
917                         }
918
919                         if (wim->hdr.part_number != 1) {
920                                 WARNING("Ignoring metadata resource found in a "
921                                         "non-first part of the split WIM");
922                                 goto free_cur_entry_and_continue;
923                         }
924
925                         /* The number of entries in the lookup table with
926                          * WIM_RESHDR_FLAG_METADATA set should be the same as
927                          * the image_count field in the WIM header.  */
928                         if (image_index == wim->hdr.image_count) {
929                                 WARNING("Found more metadata resources than images");
930                                 goto free_cur_entry_and_continue;
931                         }
932
933                         /* Notice very carefully:  We are assigning the metadata
934                          * resources to images in the same order in which their
935                          * lookup table entries occur on disk.  (This is also
936                          * the behavior of Microsoft's software.)  In
937                          * particular, this overrides the actual locations of
938                          * the metadata resources themselves in the WIM file as
939                          * well as any information written in the XML data.  */
940                         DEBUG("Found metadata resource for image %"PRIu32" at "
941                               "offset %"PRIu64".",
942                               image_index + 1,
943                               reshdr.offset_in_wim);
944
945                         wim->image_metadata[image_index++]->metadata_lte = cur_entry;
946                 } else {
947                         /* Lookup table entry for a non-metadata stream.  */
948
949                         /* Ignore this stream if it's a duplicate.  */
950                         duplicate_entry = lookup_stream(table, cur_entry->hash);
951                         if (duplicate_entry) {
952                                 num_duplicate_entries++;
953                                 goto free_cur_entry_and_continue;
954                         }
955
956                         /* Insert the stream into the in-memory lookup table,
957                          * keyed by its SHA1 message digest.  */
958                         lookup_table_insert(table, cur_entry);
959                 }
960
961                 /* Add the stream to the current resource specification.  */
962                 lte_bind_wim_resource_spec(cur_entry, cur_rspec);
963                 if (reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
964                         /* In packed runs, the offset field is used for
965                          * in-resource offset, not the in-WIM offset, and the
966                          * size field is used for the uncompressed size, not the
967                          * compressed size.  */
968                         cur_entry->offset_in_res = reshdr.offset_in_wim;
969                         cur_entry->size = reshdr.size_in_wim;
970                         cur_entry->flags = reshdr.flags;
971                         /* cur_rspec stays the same  */
972
973                 } else {
974                         /* Normal case: The stream corresponds one-to-one with
975                          * the resource entry.  */
976                         cur_entry->offset_in_res = 0;
977                         cur_entry->size = reshdr.uncompressed_size;
978                         cur_entry->flags = reshdr.flags;
979                         cur_rspec = NULL;
980                 }
981                 continue;
982
983         free_cur_entry_and_continue:
984                 free_lookup_table_entry(cur_entry);
985         }
986         cur_entry = NULL;
987
988         /* Validate the last resource.  */
989         if (cur_rspec) {
990                 ret = finish_resource(cur_rspec);
991                 cur_rspec = NULL;
992                 if (ret)
993                         goto out;
994         }
995
996         if (wim->hdr.part_number == 1 && image_index != wim->hdr.image_count) {
997                 WARNING("Could not find metadata resources for all images");
998                 for (u32 i = image_index; i < wim->hdr.image_count; i++)
999                         put_image_metadata(wim->image_metadata[i], NULL);
1000                 wim->hdr.image_count = image_index;
1001         }
1002
1003         if (num_duplicate_entries > 0) {
1004                 WARNING("Ignoring %zu duplicate streams in the WIM lookup table",
1005                         num_duplicate_entries);
1006         }
1007
1008         if (num_wrong_part_entries > 0) {
1009                 WARNING("Ignoring %zu streams with wrong part number",
1010                         num_wrong_part_entries);
1011         }
1012
1013         DEBUG("Done reading lookup table.");
1014         wim->lookup_table = table;
1015         table = NULL;
1016         ret = 0;
1017         goto out;
1018 oom:
1019         ERROR("Not enough memory to read lookup table!");
1020         ret = WIMLIB_ERR_NOMEM;
1021 out:
1022         if (cur_rspec && list_empty(&cur_rspec->stream_list))
1023                 FREE(cur_rspec);
1024         free_lookup_table_entry(cur_entry);
1025         free_lookup_table(table);
1026         FREE(buf);
1027         return ret;
1028 }
1029
1030 static void
1031 put_wim_lookup_table_entry(struct wim_lookup_table_entry_disk *disk_entry,
1032                            const struct wim_reshdr *out_reshdr,
1033                            u16 part_number, u32 refcnt, const u8 *hash)
1034 {
1035         put_wim_reshdr(out_reshdr, &disk_entry->reshdr);
1036         disk_entry->part_number = cpu_to_le16(part_number);
1037         disk_entry->refcnt = cpu_to_le32(refcnt);
1038         copy_hash(disk_entry->hash, hash);
1039 }
1040
1041 int
1042 write_wim_lookup_table_from_stream_list(struct list_head *stream_list,
1043                                         struct filedes *out_fd,
1044                                         u16 part_number,
1045                                         struct wim_reshdr *out_reshdr,
1046                                         int write_resource_flags)
1047 {
1048         size_t table_size;
1049         struct wim_lookup_table_entry *lte;
1050         struct wim_lookup_table_entry_disk *table_buf;
1051         struct wim_lookup_table_entry_disk *table_buf_ptr;
1052         int ret;
1053         u64 prev_res_offset_in_wim = ~0ULL;
1054
1055         table_size = 0;
1056         list_for_each_entry(lte, stream_list, lookup_table_list) {
1057                 table_size += sizeof(struct wim_lookup_table_entry_disk);
1058
1059                 if (lte->out_reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS &&
1060                     lte->out_res_offset_in_wim != prev_res_offset_in_wim)
1061                 {
1062                         table_size += sizeof(struct wim_lookup_table_entry_disk);
1063                         prev_res_offset_in_wim = lte->out_res_offset_in_wim;
1064                 }
1065         }
1066
1067         DEBUG("Writing WIM lookup table (size=%zu, offset=%"PRIu64")",
1068               table_size, out_fd->offset);
1069
1070         table_buf = MALLOC(table_size);
1071         if (table_buf == NULL) {
1072                 ERROR("Failed to allocate %zu bytes for temporary lookup table",
1073                       table_size);
1074                 return WIMLIB_ERR_NOMEM;
1075         }
1076         table_buf_ptr = table_buf;
1077
1078         prev_res_offset_in_wim = ~0ULL;
1079         list_for_each_entry(lte, stream_list, lookup_table_list) {
1080
1081                 put_wim_lookup_table_entry(table_buf_ptr++,
1082                                            &lte->out_reshdr,
1083                                            part_number,
1084                                            lte->out_refcnt,
1085                                            lte->hash);
1086                 if (lte->out_reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS &&
1087                     lte->out_res_offset_in_wim != prev_res_offset_in_wim)
1088                 {
1089                         /* Put the main resource entry for the pack.  */
1090
1091                         struct wim_reshdr reshdr;
1092
1093                         reshdr.offset_in_wim = lte->out_res_offset_in_wim;
1094                         reshdr.size_in_wim = lte->out_res_size_in_wim;
1095                         reshdr.uncompressed_size = WIM_PACK_MAGIC_NUMBER;
1096                         reshdr.flags = WIM_RESHDR_FLAG_PACKED_STREAMS;
1097
1098                         DEBUG("Putting main entry for pack: "
1099                               "size_in_wim=%"PRIu64", "
1100                               "offset_in_wim=%"PRIu64", "
1101                               "uncompressed_size=%"PRIu64,
1102                               reshdr.size_in_wim,
1103                               reshdr.offset_in_wim,
1104                               reshdr.uncompressed_size);
1105
1106                         put_wim_lookup_table_entry(table_buf_ptr++,
1107                                                    &reshdr,
1108                                                    part_number,
1109                                                    1, zero_hash);
1110                         prev_res_offset_in_wim = lte->out_res_offset_in_wim;
1111                 }
1112
1113         }
1114         wimlib_assert((u8*)table_buf_ptr - (u8*)table_buf == table_size);
1115
1116         /* Write the lookup table uncompressed.  Although wimlib can handle a
1117          * compressed lookup table, MS software cannot.  */
1118         ret = write_wim_resource_from_buffer(table_buf,
1119                                              table_size,
1120                                              WIM_RESHDR_FLAG_METADATA,
1121                                              out_fd,
1122                                              WIMLIB_COMPRESSION_TYPE_NONE,
1123                                              0,
1124                                              out_reshdr,
1125                                              NULL,
1126                                              write_resource_flags);
1127         FREE(table_buf);
1128         DEBUG("ret=%d", ret);
1129         return ret;
1130 }
1131
1132 int
1133 lte_zero_real_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
1134 {
1135         lte->real_refcnt = 0;
1136         return 0;
1137 }
1138
1139 int
1140 lte_zero_out_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
1141 {
1142         lte->out_refcnt = 0;
1143         return 0;
1144 }
1145
1146 int
1147 lte_free_extracted_file(struct wim_lookup_table_entry *lte, void *_ignore)
1148 {
1149         if (lte->extracted_file != NULL) {
1150                 FREE(lte->extracted_file);
1151                 lte->extracted_file = NULL;
1152         }
1153         return 0;
1154 }
1155
1156 /* Allocate a stream entry for the contents of the buffer, or re-use an existing
1157  * entry in @lookup_table for the same stream.  */
1158 struct wim_lookup_table_entry *
1159 new_stream_from_data_buffer(const void *buffer, size_t size,
1160                             struct wim_lookup_table *lookup_table)
1161 {
1162         u8 hash[SHA1_HASH_SIZE];
1163         struct wim_lookup_table_entry *lte, *existing_lte;
1164
1165         sha1_buffer(buffer, size, hash);
1166         existing_lte = lookup_stream(lookup_table, hash);
1167         if (existing_lte) {
1168                 wimlib_assert(existing_lte->size == size);
1169                 lte = existing_lte;
1170                 lte->refcnt++;
1171         } else {
1172                 void *buffer_copy;
1173                 lte = new_lookup_table_entry();
1174                 if (lte == NULL)
1175                         return NULL;
1176                 buffer_copy = memdup(buffer, size);
1177                 if (buffer_copy == NULL) {
1178                         free_lookup_table_entry(lte);
1179                         return NULL;
1180                 }
1181                 lte->resource_location  = RESOURCE_IN_ATTACHED_BUFFER;
1182                 lte->attached_buffer    = buffer_copy;
1183                 lte->size               = size;
1184                 copy_hash(lte->hash, hash);
1185                 lookup_table_insert(lookup_table, lte);
1186         }
1187         return lte;
1188 }
1189
1190 /* Calculate the SHA1 message digest of a stream and move it from the list of
1191  * unhashed streams to the stream lookup table, possibly joining it with an
1192  * existing lookup table entry for an identical stream.
1193  *
1194  * @lte:  An unhashed lookup table entry.
1195  * @lookup_table:  Lookup table for the WIM.
1196  * @lte_ret:  On success, write a pointer to the resulting lookup table
1197  *            entry to this location.  This will be the same as @lte
1198  *            if it was inserted into the lookup table, or different if
1199  *            a duplicate stream was found.
1200  *
1201  * Returns 0 on success; nonzero if there is an error reading the stream.
1202  */
1203 int
1204 hash_unhashed_stream(struct wim_lookup_table_entry *lte,
1205                      struct wim_lookup_table *lookup_table,
1206                      struct wim_lookup_table_entry **lte_ret)
1207 {
1208         int ret;
1209         struct wim_lookup_table_entry *duplicate_lte;
1210         struct wim_lookup_table_entry **back_ptr;
1211
1212         wimlib_assert(lte->unhashed);
1213
1214         /* back_ptr must be saved because @back_inode and @back_stream_id are in
1215          * union with the SHA1 message digest and will no longer be valid once
1216          * the SHA1 has been calculated. */
1217         back_ptr = retrieve_lte_pointer(lte);
1218
1219         ret = sha1_stream(lte);
1220         if (ret)
1221                 return ret;
1222
1223         /* Look for a duplicate stream */
1224         duplicate_lte = lookup_stream(lookup_table, lte->hash);
1225         list_del(&lte->unhashed_list);
1226         if (duplicate_lte) {
1227                 /* We have a duplicate stream.  Transfer the reference counts
1228                  * from this stream to the duplicate and update the reference to
1229                  * this stream (in an inode or ads_entry) to point to the
1230                  * duplicate.  The caller is responsible for freeing @lte if
1231                  * needed.  */
1232                 wimlib_assert(!(duplicate_lte->unhashed));
1233                 wimlib_assert(duplicate_lte->size == lte->size);
1234                 duplicate_lte->refcnt += lte->refcnt;
1235                 lte->refcnt = 0;
1236                 *back_ptr = duplicate_lte;
1237                 lte = duplicate_lte;
1238         } else {
1239                 /* No duplicate stream, so we need to insert this stream into
1240                  * the lookup table and treat it as a hashed stream. */
1241                 lookup_table_insert(lookup_table, lte);
1242                 lte->unhashed = 0;
1243         }
1244         *lte_ret = lte;
1245         return 0;
1246 }
1247
1248 void
1249 lte_to_wimlib_resource_entry(const struct wim_lookup_table_entry *lte,
1250                              struct wimlib_resource_entry *wentry)
1251 {
1252         memset(wentry, 0, sizeof(*wentry));
1253
1254         wentry->uncompressed_size = lte->size;
1255         if (lte->resource_location == RESOURCE_IN_WIM) {
1256                 wentry->part_number = lte->rspec->wim->hdr.part_number;
1257                 if (lte->flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
1258                         wentry->compressed_size = 0;
1259                         wentry->offset = lte->offset_in_res;
1260                 } else {
1261                         wentry->compressed_size = lte->rspec->size_in_wim;
1262                         wentry->offset = lte->rspec->offset_in_wim;
1263                 }
1264                 wentry->raw_resource_offset_in_wim = lte->rspec->offset_in_wim;
1265                 /*wentry->raw_resource_uncompressed_size = lte->rspec->uncompressed_size;*/
1266                 wentry->raw_resource_compressed_size = lte->rspec->size_in_wim;
1267         }
1268         copy_hash(wentry->sha1_hash, lte->hash);
1269         wentry->reference_count = lte->refcnt;
1270         wentry->is_compressed = (lte->flags & WIM_RESHDR_FLAG_COMPRESSED) != 0;
1271         wentry->is_metadata = (lte->flags & WIM_RESHDR_FLAG_METADATA) != 0;
1272         wentry->is_free = (lte->flags & WIM_RESHDR_FLAG_FREE) != 0;
1273         wentry->is_spanned = (lte->flags & WIM_RESHDR_FLAG_SPANNED) != 0;
1274         wentry->packed = (lte->flags & WIM_RESHDR_FLAG_PACKED_STREAMS) != 0;
1275 }
1276
1277 struct iterate_lte_context {
1278         wimlib_iterate_lookup_table_callback_t cb;
1279         void *user_ctx;
1280 };
1281
1282 static int
1283 do_iterate_lte(struct wim_lookup_table_entry *lte, void *_ctx)
1284 {
1285         struct iterate_lte_context *ctx = _ctx;
1286         struct wimlib_resource_entry entry;
1287
1288         lte_to_wimlib_resource_entry(lte, &entry);
1289         return (*ctx->cb)(&entry, ctx->user_ctx);
1290 }
1291
1292 /* API function documented in wimlib.h  */
1293 WIMLIBAPI int
1294 wimlib_iterate_lookup_table(WIMStruct *wim, int flags,
1295                             wimlib_iterate_lookup_table_callback_t cb,
1296                             void *user_ctx)
1297 {
1298         if (flags != 0)
1299                 return WIMLIB_ERR_INVALID_PARAM;
1300
1301         struct iterate_lte_context ctx = {
1302                 .cb = cb,
1303                 .user_ctx = user_ctx,
1304         };
1305         if (wim->hdr.part_number == 1) {
1306                 int ret;
1307                 for (int i = 0; i < wim->hdr.image_count; i++) {
1308                         ret = do_iterate_lte(wim->image_metadata[i]->metadata_lte,
1309                                              &ctx);
1310                         if (ret)
1311                                 return ret;
1312                 }
1313         }
1314         return for_lookup_table_entry(wim->lookup_table, do_iterate_lte, &ctx);
1315 }