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   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/endianness.h"
  32 #include "wimlib/error.h"
  33 #include "wimlib/file_io.h"
  34 #include "wimlib/glob.h"
  35 #include "wimlib/lookup_table.h"
  36 #include "wimlib/metadata.h"
  37 #include "wimlib/paths.h"
  38 #include "wimlib/resource.h"
  39 #include "wimlib/util.h"
  40 #include "wimlib/write.h"
  41
  42 #include <errno.h>
  43 #include <stdlib.h>
  44 #ifdef WITH_FUSE
  45 #  include <unistd.h> /* for unlink() */
  46 #endif
  47
  48 struct wim_lookup_table *
  49 new_lookup_table(size_t capacity)
  50 {
  51         struct wim_lookup_table *table;
  52         struct hlist_head *array;
  53
  54         table = CALLOC(1, sizeof(struct wim_lookup_table));
  55         if (table) {
  56                 array = CALLOC(capacity, sizeof(array[0]));
  57                 if (array) {
  58                         table->num_entries = 0;
  59                         table->capacity = capacity;
  60                         table->array = array;
  61                 } else {
  62                         FREE(table);
  63                         table = NULL;
  64                         ERROR("Failed to allocate memory for lookup table "
  65                               "with capacity %zu", capacity);
  66                 }
  67         }
  68         return table;
  69 }
  70
  71 struct wim_lookup_table_entry *
  72 new_lookup_table_entry(void)
  73 {
  74         struct wim_lookup_table_entry *lte;
  75
  76         lte = CALLOC(1, sizeof(struct wim_lookup_table_entry));
  77         if (lte == NULL) {
  78                 ERROR("Out of memory (tried to allocate %zu bytes for "
  79                       "lookup table entry)",
  80                       sizeof(struct wim_lookup_table_entry));
  81                 return NULL;
  82         }
  83         lte->refcnt = 1;
  84         BUILD_BUG_ON(RESOURCE_NONEXISTENT != 0);
  85         return lte;
  86 }
  87
  88 struct wim_lookup_table_entry *
  89 clone_lookup_table_entry(const struct wim_lookup_table_entry *old)
  90 {
  91         struct wim_lookup_table_entry *new;
  92
  93         new = memdup(old, sizeof(struct wim_lookup_table_entry));
  94         if (new == NULL)
  95                 return NULL;
  96
  97         new->extracted_file = NULL;
  98         switch (new->resource_location) {
  99         case RESOURCE_IN_WIM:
 100                 list_add(&new->rspec_node, &new->rspec->stream_list);
 101                 break;
 102
 103         case RESOURCE_IN_FILE_ON_DISK:
 104 #ifdef __WIN32__
 105         case RESOURCE_WIN32_ENCRYPTED:
 106 #endif
 107 #ifdef WITH_FUSE
 108         case RESOURCE_IN_STAGING_FILE:
 109                 BUILD_BUG_ON((void*)&old->file_on_disk !=
 110                              (void*)&old->staging_file_name);
 111 #endif
 112                 new->file_on_disk = TSTRDUP(old->file_on_disk);
 113                 if (new->file_on_disk == NULL)
 114                         goto out_free;
 115                 break;
 116         case RESOURCE_IN_ATTACHED_BUFFER:
 117                 new->attached_buffer = memdup(old->attached_buffer, old->size);
 118                 if (new->attached_buffer == NULL)
 119                         goto out_free;
 120                 break;
 121 #ifdef WITH_NTFS_3G
 122         case RESOURCE_IN_NTFS_VOLUME:
 123                 if (old->ntfs_loc) {
 124                         struct ntfs_location *loc;
 125                         loc = memdup(old->ntfs_loc, sizeof(struct ntfs_location));
 126                         if (loc == NULL)
 127                                 goto out_free;
 128                         loc->path = NULL;
 129                         loc->stream_name = NULL;
 130                         new->ntfs_loc = loc;
 131                         loc->path = STRDUP(old->ntfs_loc->path);
 132                         if (loc->path == NULL)
 133                                 goto out_free;
 134                         if (loc->stream_name_nchars != 0) {
 135                                 loc->stream_name = memdup(old->ntfs_loc->stream_name,
 136                                                           loc->stream_name_nchars * 2);
 137                                 if (loc->stream_name == NULL)
 138                                         goto out_free;
 139                         }
 140                 }
 141                 break;
 142 #endif
 143         default:
 144                 break;
 145         }
 146         return new;
 147 out_free:
 148         free_lookup_table_entry(new);
 149         return NULL;
 150 }
 151
 152 void
 153 free_lookup_table_entry(struct wim_lookup_table_entry *lte)
 154 {
 155         if (lte) {
 156                 switch (lte->resource_location) {
 157                 case RESOURCE_IN_WIM:
 158                         list_del(&lte->rspec_node);
 159                         if (list_empty(&lte->rspec->stream_list))
 160                                 FREE(lte->rspec);
 161                         break;
 162                 case RESOURCE_IN_FILE_ON_DISK:
 163         #ifdef __WIN32__
 164                 case RESOURCE_WIN32_ENCRYPTED:
 165         #endif
 166         #ifdef WITH_FUSE
 167                 case RESOURCE_IN_STAGING_FILE:
 168                         BUILD_BUG_ON((void*)&lte->file_on_disk !=
 169                                      (void*)&lte->staging_file_name);
 170         #endif
 171                 case RESOURCE_IN_ATTACHED_BUFFER:
 172                         BUILD_BUG_ON((void*)&lte->file_on_disk !=
 173                                      (void*)&lte->attached_buffer);
 174                         FREE(lte->file_on_disk);
 175                         break;
 176 #ifdef WITH_NTFS_3G
 177                 case RESOURCE_IN_NTFS_VOLUME:
 178                         if (lte->ntfs_loc) {
 179                                 FREE(lte->ntfs_loc->path);
 180                                 FREE(lte->ntfs_loc->stream_name);
 181                                 FREE(lte->ntfs_loc);
 182                         }
 183                         break;
 184 #endif
 185                 default:
 186                         break;
 187                 }
 188                 FREE(lte);
 189         }
 190 }
 191
 192 static int
 193 do_free_lookup_table_entry(struct wim_lookup_table_entry *entry, void *ignore)
 194 {
 195         free_lookup_table_entry(entry);
 196         return 0;
 197 }
 198
 199
 200 void
 201 free_lookup_table(struct wim_lookup_table *table)
 202 {
 203         DEBUG("Freeing lookup table.");
 204         if (table) {
 205                 if (table->array) {
 206                         for_lookup_table_entry(table,
 207                                                do_free_lookup_table_entry,
 208                                                NULL);
 209                         FREE(table->array);
 210                 }
 211                 FREE(table);
 212         }
 213 }
 214
 215 /*
 216  * Inserts an entry into the lookup table.
 217  *
 218  * @table:      A pointer to the lookup table.
 219  * @lte:        A pointer to the entry to insert.
 220  */
 221 void
 222 lookup_table_insert(struct wim_lookup_table *table,
 223                     struct wim_lookup_table_entry *lte)
 224 {
 225         size_t i = lte->hash_short % table->capacity;
 226         hlist_add_head(&lte->hash_list, &table->array[i]);
 227
 228         /* XXX Make the table grow when too many entries have been inserted. */
 229         table->num_entries++;
 230 }
 231
 232 static void
 233 finalize_lte(struct wim_lookup_table_entry *lte)
 234 {
 235         #ifdef WITH_FUSE
 236         if (lte->resource_location == RESOURCE_IN_STAGING_FILE) {
 237                 unlink(lte->staging_file_name);
 238                 list_del(&lte->unhashed_list);
 239         }
 240         #endif
 241         free_lookup_table_entry(lte);
 242 }
 243
 244 /* Decrements the reference count for the lookup table entry @lte.  If its
 245  * reference count reaches 0, it is unlinked from the lookup table.  If,
 246  * furthermore, the entry has no opened file descriptors associated with it, the
 247  * entry is freed.  */
 248 void
 249 lte_decrement_refcnt(struct wim_lookup_table_entry *lte,
 250                      struct wim_lookup_table *table)
 251 {
 252         wimlib_assert(lte != NULL);
 253         wimlib_assert(lte->refcnt != 0);
 254         if (--lte->refcnt == 0) {
 255                 if (lte->unhashed)
 256                         list_del(&lte->unhashed_list);
 257                 else
 258                         lookup_table_unlink(table, lte);
 259         #ifdef WITH_FUSE
 260                 if (lte->num_opened_fds == 0)
 261         #endif
 262                         finalize_lte(lte);
 263         }
 264 }
 265
 266 #ifdef WITH_FUSE
 267 void
 268 lte_decrement_num_opened_fds(struct wim_lookup_table_entry *lte)
 269 {
 270         if (lte->num_opened_fds != 0)
 271                 if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
 272                         finalize_lte(lte);
 273 }
 274 #endif
 275
 276 /* Calls a function on all the entries in the WIM lookup table.  Stop early and
 277  * return nonzero if any call to the function returns nonzero. */
 278 int
 279 for_lookup_table_entry(struct wim_lookup_table *table,
 280                        int (*visitor)(struct wim_lookup_table_entry *, void *),
 281                        void *arg)
 282 {
 283         struct wim_lookup_table_entry *lte;
 284         struct hlist_node *pos, *tmp;
 285         int ret;
 286
 287         for (size_t i = 0; i < table->capacity; i++) {
 288                 hlist_for_each_entry_safe(lte, pos, tmp, &table->array[i],
 289                                           hash_list)
 290                 {
 291                         wimlib_assert2(!(lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA));
 292                         ret = visitor(lte, arg);
 293                         if (ret)
 294                                 return ret;
 295                 }
 296         }
 297         return 0;
 298 }
 299
 300 /* qsort() callback that sorts streams (represented by `struct
 301  * wim_lookup_table_entry's) into an order optimized for reading.
 302  *
 303  * Sorting is done primarily by resource location, then secondarily by a
 304  * per-resource location order.  For example, resources in WIM files are sorted
 305  * primarily by part number, then secondarily by offset, as to implement optimal
 306  * reading of either a standalone or split WIM.  */
 307 static int
 308 cmp_streams_by_sequential_order(const void *p1, const void *p2)
 309 {
 310         const struct wim_lookup_table_entry *lte1, *lte2;
 311         int v;
 312         WIMStruct *wim1, *wim2;
 313
 314         lte1 = *(const struct wim_lookup_table_entry**)p1;
 315         lte2 = *(const struct wim_lookup_table_entry**)p2;
 316
 317         v = (int)lte1->resource_location - (int)lte2->resource_location;
 318
 319         /* Different resource locations?  */
 320         if (v)
 321                 return v;
 322
 323         switch (lte1->resource_location) {
 324         case RESOURCE_IN_WIM:
 325                 wim1 = lte1->rspec->wim;
 326                 wim2 = lte2->rspec->wim;
 327
 328                 /* Different (possibly split) WIMs?  */
 329                 if (wim1 != wim2) {
 330                         v = memcmp(wim1->hdr.guid, wim2->hdr.guid, WIM_GID_LEN);
 331                         if (v)
 332                                 return v;
 333                 }
 334
 335                 /* Different part numbers in the same WIM?  */
 336                 v = (int)wim1->hdr.part_number - (int)wim2->hdr.part_number;
 337                 if (v)
 338                         return v;
 339
 340                 if (lte1->rspec->offset_in_wim != lte2->rspec->offset_in_wim)
 341                         return cmp_u64(lte1->rspec->offset_in_wim,
 342                                        lte2->rspec->offset_in_wim);
 343
 344                 return cmp_u64(lte1->offset_in_res, lte2->offset_in_res);
 345
 346         case RESOURCE_IN_FILE_ON_DISK:
 347 #ifdef WITH_FUSE
 348         case RESOURCE_IN_STAGING_FILE:
 349 #endif
 350 #ifdef __WIN32__
 351         case RESOURCE_WIN32_ENCRYPTED:
 352 #endif
 353                 /* Compare files by path: just a heuristic that will place files
 354                  * in the same directory next to each other.  */
 355                 return tstrcmp(lte1->file_on_disk, lte2->file_on_disk);
 356 #ifdef WITH_NTFS_3G
 357         case RESOURCE_IN_NTFS_VOLUME:
 358                 return tstrcmp(lte1->ntfs_loc->path, lte2->ntfs_loc->path);
 359 #endif
 360         default:
 361                 /* No additional sorting order defined for this resource
 362                  * location (e.g. RESOURCE_IN_ATTACHED_BUFFER); simply compare
 363                  * everything equal to each other.  */
 364                 return 0;
 365         }
 366 }
 367
 368 int
 369 sort_stream_list(struct list_head *stream_list,
 370                  size_t list_head_offset,
 371                  int (*compar)(const void *, const void*))
 372 {
 373         struct list_head *cur;
 374         struct wim_lookup_table_entry **array;
 375         size_t i;
 376         size_t array_size;
 377         size_t num_streams = 0;
 378
 379         list_for_each(cur, stream_list)
 380                 num_streams++;
 381
 382         if (num_streams <= 1)
 383                 return 0;
 384
 385         array_size = num_streams * sizeof(array[0]);
 386         array = MALLOC(array_size);
 387         if (array == NULL)
 388                 return WIMLIB_ERR_NOMEM;
 389
 390         cur = stream_list->next;
 391         for (i = 0; i < num_streams; i++) {
 392                 array[i] = (struct wim_lookup_table_entry*)((u8*)cur -
 393                                                             list_head_offset);
 394                 cur = cur->next;
 395         }
 396
 397         qsort(array, num_streams, sizeof(array[0]), compar);
 398
 399         INIT_LIST_HEAD(stream_list);
 400         for (i = 0; i < num_streams; i++) {
 401                 list_add_tail((struct list_head*)
 402                                ((u8*)array[i] + list_head_offset),
 403                               stream_list);
 404         }
 405         FREE(array);
 406         return 0;
 407 }
 408
 409 /* Sort the specified list of streams in an order optimized for reading.  */
 410 int
 411 sort_stream_list_by_sequential_order(struct list_head *stream_list,
 412                                      size_t list_head_offset)
 413 {
 414         return sort_stream_list(stream_list, list_head_offset,
 415                                 cmp_streams_by_sequential_order);
 416 }
 417
 418
 419 static int
 420 add_lte_to_array(struct wim_lookup_table_entry *lte,
 421                  void *_pp)
 422 {
 423         struct wim_lookup_table_entry ***pp = _pp;
 424         *(*pp)++ = lte;
 425         return 0;
 426 }
 427
 428 /* Iterate through the lookup table entries, but first sort them by stream
 429  * offset in the WIM.  Caution: this is intended to be used when the stream
 430  * offset field has actually been set. */
 431 int
 432 for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
 433                                   int (*visitor)(struct wim_lookup_table_entry *,
 434                                                  void *),
 435                                   void *arg)
 436 {
 437         struct wim_lookup_table_entry **lte_array, **p;
 438         size_t num_streams = table->num_entries;
 439         int ret;
 440
 441         lte_array = MALLOC(num_streams * sizeof(lte_array[0]));
 442         if (!lte_array)
 443                 return WIMLIB_ERR_NOMEM;
 444         p = lte_array;
 445         for_lookup_table_entry(table, add_lte_to_array, &p);
 446
 447         wimlib_assert(p == lte_array + num_streams);
 448
 449         qsort(lte_array, num_streams, sizeof(lte_array[0]),
 450               cmp_streams_by_sequential_order);
 451         ret = 0;
 452         for (size_t i = 0; i < num_streams; i++) {
 453                 ret = visitor(lte_array[i], arg);
 454                 if (ret)
 455                         break;
 456         }
 457         FREE(lte_array);
 458         return ret;
 459 }
 460
 461 /* On-disk format of a WIM lookup table entry (stream entry). */
 462 struct wim_lookup_table_entry_disk {
 463         /* Size, offset, and flags of the stream.  */
 464         struct wim_reshdr_disk reshdr;
 465
 466         /* Which part of the split WIM this stream is in; indexed from 1. */
 467         le16 part_number;
 468
 469         /* Reference count of this stream over all WIM images. */
 470         le32 refcnt;
 471
 472         /* SHA1 message digest of the uncompressed data of this stream, or
 473          * optionally all zeroes if this stream is of zero length. */
 474         u8 hash[SHA1_HASH_SIZE];
 475 } _packed_attribute;
 476
 477 #define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
 478
 479 /* Validate the size and location of a WIM resource.  */
 480 static int
 481 validate_resource(const struct wim_resource_spec *rspec)
 482 {
 483         struct wim_lookup_table_entry *lte;
 484         u64 cur_offset;
 485
 486         /* Verify that calculating the offset of the end of the resource doesn't
 487          * overflow.  */
 488         if (rspec->offset_in_wim + rspec->size_in_wim < rspec->size_in_wim)
 489                 goto invalid;
 490
 491         /* Verify that each stream in the resource has a valid offset and size,
 492          * and that no streams overlap, and that the streams were added in order
 493          * of increasing offset.  */
 494         cur_offset = 0;
 495         list_for_each_entry(lte, &rspec->stream_list, rspec_node) {
 496                 if (lte->offset_in_res + lte->size < lte->size ||
 497                     lte->offset_in_res + lte->size > rspec->uncompressed_size ||
 498                     lte->offset_in_res < cur_offset)
 499                         goto invalid;
 500
 501                 cur_offset = lte->offset_in_res + lte->size;
 502         }
 503         return 0;
 504
 505 invalid:
 506
 507         ERROR("Invalid resource entry!");
 508         return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 509 }
 510
 511 /*
 512  * Reads the lookup table from a WIM file.  Each entry specifies a stream that
 513  * the WIM file contains, along with its location and SHA1 message digest.
 514  *
 515  * Saves lookup table entries for non-metadata streams in a hash table, and
 516  * saves the metadata entry for each image in a special per-image location (the
 517  * image_metadata array).
 518  *
 519  * Return values:
 520  *      WIMLIB_ERR_SUCCESS (0)
 521  *      WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY
 522  *      WIMLIB_ERR_RESOURCE_NOT_FOUND
 523  *
 524  *      Or an error code caused by failure to read the lookup table into memory.
 525  */
 526 int
 527 read_wim_lookup_table(WIMStruct *wim)
 528 {
 529         int ret;
 530         size_t i;
 531         size_t num_entries;
 532         struct wim_lookup_table *table;
 533         struct wim_lookup_table_entry *cur_entry, *duplicate_entry;
 534         struct wim_resource_spec *cur_rspec;
 535         void *buf;
 536         bool back_to_back_pack;
 537
 538         DEBUG("Reading lookup table.");
 539
 540         /* Sanity check: lookup table entries are 50 bytes each.  */
 541         BUILD_BUG_ON(sizeof(struct wim_lookup_table_entry_disk) !=
 542                      WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE);
 543
 544         /* Calculate number of entries in the lookup table.  */
 545         num_entries = wim->hdr.lookup_table_reshdr.uncompressed_size /
 546                       sizeof(struct wim_lookup_table_entry_disk);
 547
 548         /* Read the lookup table into a buffer.  */
 549         ret = wim_reshdr_to_data(&wim->hdr.lookup_table_reshdr, wim, &buf);
 550         if (ret)
 551                 goto out;
 552
 553         /* Allocate a hash table to map SHA1 message digests into stream
 554          * specifications.  This is the in-memory "lookup table".  */
 555         table = new_lookup_table(num_entries * 2 + 1);
 556         if (table == NULL) {
 557                 ERROR("Not enough memory to read lookup table.");
 558                 ret = WIMLIB_ERR_NOMEM;
 559                 goto out_free_buf;
 560         }
 561
 562         /* Allocate and initalize stream entries from the raw lookup table
 563          * buffer.  */
 564         wim->current_image = 0;
 565         cur_rspec = NULL;
 566         for (i = 0; i < num_entries; i++) {
 567                 const struct wim_lookup_table_entry_disk *disk_entry =
 568                         &((const struct wim_lookup_table_entry_disk*)buf)[i];
 569                 u16 part_number;
 570                 struct wim_reshdr reshdr;
 571
 572                 get_wim_reshdr(&disk_entry->reshdr, &reshdr);
 573
 574                 DEBUG("reshdr: size_in_wim=%"PRIu64", "
 575                       "uncompressed_size=%"PRIu64", "
 576                       "offset_in_wim=%"PRIu64", "
 577                       "flags=0x%02x",
 578                       reshdr.size_in_wim, reshdr.uncompressed_size,
 579                       reshdr.offset_in_wim, reshdr.flags);
 580
 581                 if (wim->hdr.wim_version == WIM_VERSION_DEFAULT)
 582                         reshdr.flags &= ~WIM_RESHDR_FLAG_PACKED_STREAMS;
 583
 584                 cur_entry = new_lookup_table_entry();
 585                 if (cur_entry == NULL) {
 586                         ERROR("Not enough memory to read lookup table!");
 587                         ret = WIMLIB_ERR_NOMEM;
 588                         goto out_free_lookup_table;
 589                 }
 590
 591                 part_number = le16_to_cpu(disk_entry->part_number);
 592                 cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
 593                 copy_hash(cur_entry->hash, disk_entry->hash);
 594
 595                 if (part_number != wim->hdr.part_number) {
 596                         WARNING("A lookup table entry in part %hu of the WIM "
 597                                 "points to part %hu (ignoring it)",
 598                                 wim->hdr.part_number, part_number);
 599                         free_lookup_table_entry(cur_entry);
 600                         continue;
 601                 }
 602
 603                 if (!(reshdr.flags & (WIM_RESHDR_FLAG_PACKED_STREAMS |
 604                                       WIM_RESHDR_FLAG_COMPRESSED))) {
 605                         if (reshdr.uncompressed_size != reshdr.size_in_wim) {
 606                                 ERROR("Invalid resource entry!");
 607                                 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 608                                 goto out_free_cur_entry;
 609                         }
 610                 }
 611
 612                 back_to_back_pack = false;
 613                 if (!(reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) ||
 614                     cur_rspec == NULL ||
 615                     (back_to_back_pack =
 616                      ((reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) &&
 617                       reshdr.uncompressed_size == WIM_PACK_MAGIC_NUMBER &&
 618                       cur_rspec != NULL &&
 619                       cur_rspec->size_in_wim != 0)))
 620                 {
 621                         /* Starting new run of streams that share the same WIM
 622                          * resource.  */
 623                         struct wim_lookup_table_entry *prev_entry = NULL;
 624
 625                         if (back_to_back_pack) {
 626                                 prev_entry = list_entry(cur_rspec->stream_list.prev,
 627                                                         struct wim_lookup_table_entry,
 628                                                         rspec_node);
 629                                 lte_unbind_wim_resource_spec(prev_entry);
 630                                 cur_rspec->uncompressed_size -= prev_entry->size;
 631                         }
 632                         if (cur_rspec != NULL) {
 633                                 ret = validate_resource(cur_rspec);
 634                                 if (ret)
 635                                         goto out_free_cur_entry;
 636                         }
 637
 638                         /* Allocate the resource specification and initialize it
 639                          * with values from the current stream entry.  */
 640                         cur_rspec = MALLOC(sizeof(*cur_rspec));
 641                         if (cur_rspec == NULL) {
 642                                 ERROR("Not enough memory to read lookup table!");
 643                                 ret = WIMLIB_ERR_NOMEM;
 644                                 goto out_free_cur_entry;
 645                         }
 646                         wim_res_hdr_to_spec(&reshdr, wim, cur_rspec);
 647
 648                         /* If this is a packed run, the current stream entry may
 649                          * specify a stream within the resource, and not the
 650                          * resource itself.  Zero possibly irrelevant data until
 651                          * it is read for certain.  */
 652                         if (reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
 653                                 cur_rspec->size_in_wim = 0;
 654                                 cur_rspec->uncompressed_size = 0;
 655                                 cur_rspec->offset_in_wim = 0;
 656                         }
 657
 658                         if (prev_entry) {
 659                                 lte_bind_wim_resource_spec(prev_entry, cur_rspec);
 660                                 cur_rspec->uncompressed_size = prev_entry->size;
 661                         }
 662                 }
 663
 664                 if ((reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) &&
 665                     reshdr.uncompressed_size == WIM_PACK_MAGIC_NUMBER)
 666                 {
 667                         /* Found the specification for the packed resource.
 668                          * Transfer the values to the `struct
 669                          * wim_resource_spec', and discard the current stream
 670                          * since this lookup table entry did not, in fact,
 671                          * correspond to a "stream".  */
 672
 673                         cur_rspec->offset_in_wim = reshdr.offset_in_wim;
 674                         cur_rspec->size_in_wim = reshdr.size_in_wim;
 675                         cur_rspec->flags = reshdr.flags;
 676                         DEBUG("Full pack is %"PRIu64" compressed bytes "
 677                               "at file offset %"PRIu64" (flags 0x%02x)",
 678                               cur_rspec->size_in_wim,
 679                               cur_rspec->offset_in_wim,
 680                               cur_rspec->flags);
 681                         free_lookup_table_entry(cur_entry);
 682                         continue;
 683                 }
 684
 685                 if (is_zero_hash(cur_entry->hash)) {
 686                         free_lookup_table_entry(cur_entry);
 687                         continue;
 688                 }
 689
 690                 if (reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
 691                         /* Continuing the pack with another stream.  */
 692                         DEBUG("Continuing packed run with stream: "
 693                               "%"PRIu64" uncompressed bytes @ resource offset %"PRIu64")",
 694                               reshdr.size_in_wim, reshdr.offset_in_wim);
 695                         cur_rspec->uncompressed_size += reshdr.size_in_wim;
 696                 }
 697
 698                 lte_bind_wim_resource_spec(cur_entry, cur_rspec);
 699                 if (reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
 700                         /* In packed runs, the offset field is used for
 701                          * in-resource offset, not the in-WIM offset, and the
 702                          * size field is used for the uncompressed size, not the
 703                          * compressed size.  */
 704                         cur_entry->offset_in_res = reshdr.offset_in_wim;
 705                         cur_entry->size = reshdr.size_in_wim;
 706                         cur_entry->flags = reshdr.flags;
 707                 } else {
 708                         /* Normal case: The stream corresponds one-to-one with
 709                          * the resource entry.  */
 710                         cur_entry->offset_in_res = 0;
 711                         cur_entry->size = reshdr.uncompressed_size;
 712                         cur_entry->flags = reshdr.flags;
 713                         cur_rspec = NULL;
 714                 }
 715
 716                 if (cur_entry->flags & WIM_RESHDR_FLAG_METADATA) {
 717                         /* Lookup table entry for a metadata resource */
 718
 719                         /* Metadata entries with no references must be ignored;
 720                          * see for example the WinPE WIMs from the WAIK v2.1.
 721                          * */
 722                         if (cur_entry->refcnt == 0) {
 723                                 free_lookup_table_entry(cur_entry);
 724                                 continue;
 725                         }
 726
 727                         if (cur_entry->refcnt != 1) {
 728                                 if (wimlib_print_errors) {
 729                                         ERROR("Found metadata resource with refcnt != 1:");
 730                                         print_lookup_table_entry(cur_entry, stderr);
 731                                 }
 732                                 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 733                                 goto out_free_cur_entry;
 734                         }
 735
 736                         if (wim->hdr.part_number != 1) {
 737                                 WARNING("Ignoring metadata resource found in a "
 738                                         "non-first part of the split WIM");
 739                                 free_lookup_table_entry(cur_entry);
 740                                 continue;
 741                         }
 742                         if (wim->current_image == wim->hdr.image_count) {
 743                                 WARNING("The WIM header says there are %u images "
 744                                         "in the WIM, but we found more metadata "
 745                                         "resources than this (ignoring the extra)",
 746                                         wim->hdr.image_count);
 747                                 free_lookup_table_entry(cur_entry);
 748                                 continue;
 749                         }
 750
 751                         /* Notice very carefully:  We are assigning the metadata
 752                          * resources in the exact order mirrored by their lookup
 753                          * table entries on disk, which is the behavior of
 754                          * Microsoft's software.  In particular, this overrides
 755                          * the actual locations of the metadata resources
 756                          * themselves in the WIM file as well as any information
 757                          * written in the XML data. */
 758                         DEBUG("Found metadata resource for image %u at "
 759                               "offset %"PRIu64".",
 760                               wim->current_image + 1,
 761                               cur_entry->rspec->offset_in_wim);
 762                         wim->image_metadata[
 763                                 wim->current_image++]->metadata_lte = cur_entry;
 764                         continue;
 765                 }
 766
 767                 /* Lookup table entry for a stream that is not a metadata
 768                  * resource.  */
 769                 duplicate_entry = lookup_resource(table, cur_entry->hash);
 770                 if (duplicate_entry) {
 771                         if (wimlib_print_errors) {
 772                                 WARNING("The WIM lookup table contains two entries with the "
 773                                       "same SHA1 message digest!");
 774                                 WARNING("The first entry is:");
 775                                 print_lookup_table_entry(duplicate_entry, stderr);
 776                                 WARNING("The second entry is:");
 777                                 print_lookup_table_entry(cur_entry, stderr);
 778                         }
 779                         free_lookup_table_entry(cur_entry);
 780                         continue;
 781                 }
 782
 783                 /* Finally, insert the stream into the lookup table, keyed by
 784                  * its SHA1 message digest.  */
 785                 lookup_table_insert(table, cur_entry);
 786         }
 787
 788         /* Validate the last resource.  */
 789         if (cur_rspec != NULL) {
 790                 ret = validate_resource(cur_rspec);
 791                 if (ret)
 792                         goto out_free_lookup_table;
 793         }
 794
 795         if (wim->hdr.part_number == 1 && wim->current_image != wim->hdr.image_count) {
 796                 WARNING("The header of \"%"TS"\" says there are %u images in\n"
 797                         "          the WIM, but we only found %d metadata resources!  Acting as if\n"
 798                         "          the header specified only %d images instead.",
 799                         wim->filename, wim->hdr.image_count,
 800                         wim->current_image, wim->current_image);
 801                 for (int i = wim->current_image; i < wim->hdr.image_count; i++)
 802                         put_image_metadata(wim->image_metadata[i], NULL);
 803                 wim->hdr.image_count = wim->current_image;
 804         }
 805         DEBUG("Done reading lookup table.");
 806         wim->lookup_table = table;
 807         ret = 0;
 808         goto out_free_buf;
 809
 810 out_free_cur_entry:
 811         FREE(cur_entry);
 812 out_free_lookup_table:
 813         free_lookup_table(table);
 814 out_free_buf:
 815         FREE(buf);
 816 out:
 817         wim->current_image = 0;
 818         return ret;
 819 }
 820
 821 static void
 822 put_wim_lookup_table_entry(struct wim_lookup_table_entry_disk *disk_entry,
 823                            const struct wim_reshdr *out_reshdr,
 824                            u16 part_number, u32 refcnt, const u8 *hash)
 825 {
 826         put_wim_reshdr(out_reshdr, &disk_entry->reshdr);
 827         disk_entry->part_number = cpu_to_le16(part_number);
 828         disk_entry->refcnt = cpu_to_le32(refcnt);
 829         copy_hash(disk_entry->hash, hash);
 830 }
 831
 832 int
 833 write_wim_lookup_table_from_stream_list(struct list_head *stream_list,
 834                                         struct filedes *out_fd,
 835                                         u16 part_number,
 836                                         struct wim_reshdr *out_reshdr,
 837                                         int write_resource_flags,
 838                                         struct wimlib_lzx_context **comp_ctx)
 839 {
 840         size_t table_size;
 841         struct wim_lookup_table_entry *lte;
 842         struct wim_lookup_table_entry_disk *table_buf;
 843         struct wim_lookup_table_entry_disk *table_buf_ptr;
 844         int ret;
 845         u64 prev_res_offset_in_wim = ~0ULL;
 846
 847         table_size = 0;
 848         list_for_each_entry(lte, stream_list, lookup_table_list) {
 849                 table_size += sizeof(struct wim_lookup_table_entry_disk);
 850
 851                 if (lte->out_reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS &&
 852                     lte->out_res_offset_in_wim != prev_res_offset_in_wim)
 853                 {
 854                         table_size += sizeof(struct wim_lookup_table_entry_disk);
 855                         prev_res_offset_in_wim = lte->out_res_offset_in_wim;
 856                 }
 857         }
 858
 859         DEBUG("Writing WIM lookup table (size=%zu, offset=%"PRIu64")",
 860               table_size, out_fd->offset);
 861
 862         table_buf = MALLOC(table_size);
 863         if (table_buf == NULL) {
 864                 ERROR("Failed to allocate %zu bytes for temporary lookup table",
 865                       table_size);
 866                 return WIMLIB_ERR_NOMEM;
 867         }
 868         table_buf_ptr = table_buf;
 869
 870         prev_res_offset_in_wim = ~0ULL;
 871         list_for_each_entry(lte, stream_list, lookup_table_list) {
 872
 873                 put_wim_lookup_table_entry(table_buf_ptr++,
 874                                            &lte->out_reshdr,
 875                                            part_number,
 876                                            lte->out_refcnt,
 877                                            lte->hash);
 878                 if (lte->out_reshdr.flags & WIM_RESHDR_FLAG_PACKED_STREAMS &&
 879                     lte->out_res_offset_in_wim != prev_res_offset_in_wim)
 880                 {
 881                         /* Put the main resource entry for the pack.  */
 882
 883                         struct wim_reshdr reshdr;
 884
 885                         reshdr.offset_in_wim = lte->out_res_offset_in_wim;
 886                         reshdr.size_in_wim = lte->out_res_size_in_wim;
 887                         reshdr.uncompressed_size = WIM_PACK_MAGIC_NUMBER;
 888                         reshdr.flags = WIM_RESHDR_FLAG_PACKED_STREAMS;
 889
 890                         DEBUG("Putting main entry for pack: "
 891                               "size_in_wim=%"PRIu64", "
 892                               "offset_in_wim=%"PRIu64", "
 893                               "uncompressed_size=%"PRIu64,
 894                               reshdr.size_in_wim,
 895                               reshdr.offset_in_wim,
 896                               reshdr.uncompressed_size);
 897
 898                         put_wim_lookup_table_entry(table_buf_ptr++,
 899                                                    &reshdr,
 900                                                    part_number,
 901                                                    1, zero_hash);
 902                         prev_res_offset_in_wim = lte->out_res_offset_in_wim;
 903                 }
 904
 905         }
 906         wimlib_assert((u8*)table_buf_ptr - (u8*)table_buf == table_size);
 907
 908         /* Write the lookup table uncompressed.  Although wimlib can handle a
 909          * compressed lookup table, MS software cannot.  */
 910         ret = write_wim_resource_from_buffer(table_buf,
 911                                              table_size,
 912                                              WIM_RESHDR_FLAG_METADATA,
 913                                              out_fd,
 914                                              WIMLIB_COMPRESSION_TYPE_NONE,
 915                                              0,
 916                                              out_reshdr,
 917                                              NULL,
 918                                              write_resource_flags,
 919                                              comp_ctx);
 920         FREE(table_buf);
 921         DEBUG("ret=%d", ret);
 922         return ret;
 923 }
 924
 925 int
 926 lte_zero_real_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
 927 {
 928         lte->real_refcnt = 0;
 929         return 0;
 930 }
 931
 932 int
 933 lte_zero_out_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
 934 {
 935         lte->out_refcnt = 0;
 936         return 0;
 937 }
 938
 939 int
 940 lte_free_extracted_file(struct wim_lookup_table_entry *lte, void *_ignore)
 941 {
 942         if (lte->extracted_file != NULL) {
 943                 FREE(lte->extracted_file);
 944                 lte->extracted_file = NULL;
 945         }
 946         return 0;
 947 }
 948
 949 void
 950 print_lookup_table_entry(const struct wim_lookup_table_entry *lte, FILE *out)
 951 {
 952         if (lte == NULL) {
 953                 tputc(T('\n'), out);
 954                 return;
 955         }
 956
 957
 958         tprintf(T("Uncompressed size     = %"PRIu64" bytes\n"),
 959                 lte->size);
 960         if (lte->flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
 961                 tprintf(T("Offset                = %"PRIu64" bytes\n"),
 962                         lte->offset_in_res);
 963
 964                 tprintf(T("Raw uncompressed size = %"PRIu64" bytes\n"),
 965                         lte->rspec->uncompressed_size);
 966
 967                 tprintf(T("Raw compressed size   = %"PRIu64" bytes\n"),
 968                         lte->rspec->size_in_wim);
 969
 970                 tprintf(T("Raw offset            = %"PRIu64" bytes\n"),
 971                         lte->rspec->offset_in_wim);
 972         } else if (lte->resource_location == RESOURCE_IN_WIM) {
 973                 tprintf(T("Compressed size       = %"PRIu64" bytes\n"),
 974                         lte->rspec->size_in_wim);
 975
 976                 tprintf(T("Offset                = %"PRIu64" bytes\n"),
 977                         lte->rspec->offset_in_wim);
 978         }
 979
 980         tfprintf(out, T("Reference Count       = %u\n"), lte->refcnt);
 981
 982         if (lte->unhashed) {
 983                 tfprintf(out, T("(Unhashed: inode %p, stream_id = %u)\n"),
 984                          lte->back_inode, lte->back_stream_id);
 985         } else {
 986                 tfprintf(out, T("Hash                  = 0x"));
 987                 print_hash(lte->hash, out);
 988                 tputc(T('\n'), out);
 989         }
 990
 991         tfprintf(out, T("Flags                 = "));
 992         u8 flags = lte->flags;
 993         if (flags & WIM_RESHDR_FLAG_COMPRESSED)
 994                 tfputs(T("WIM_RESHDR_FLAG_COMPRESSED, "), out);
 995         if (flags & WIM_RESHDR_FLAG_FREE)
 996                 tfputs(T("WIM_RESHDR_FLAG_FREE, "), out);
 997         if (flags & WIM_RESHDR_FLAG_METADATA)
 998                 tfputs(T("WIM_RESHDR_FLAG_METADATA, "), out);
 999         if (flags & WIM_RESHDR_FLAG_SPANNED)
1000                 tfputs(T("WIM_RESHDR_FLAG_SPANNED, "), out);
1001         if (flags & WIM_RESHDR_FLAG_PACKED_STREAMS)
1002                 tfputs(T("WIM_RESHDR_FLAG_PACKED_STREAMS, "), out);
1003         tputc(T('\n'), out);
1004         switch (lte->resource_location) {
1005         case RESOURCE_IN_WIM:
1006                 if (lte->rspec->wim->filename) {
1007                         tfprintf(out, T("WIM file              = `%"TS"'\n"),
1008                                  lte->rspec->wim->filename);
1009                 }
1010                 break;
1011 #ifdef __WIN32__
1012         case RESOURCE_WIN32_ENCRYPTED:
1013 #endif
1014         case RESOURCE_IN_FILE_ON_DISK:
1015                 tfprintf(out, T("File on Disk          = `%"TS"'\n"),
1016                          lte->file_on_disk);
1017                 break;
1018 #ifdef WITH_FUSE
1019         case RESOURCE_IN_STAGING_FILE:
1020                 tfprintf(out, T("Staging File          = `%"TS"'\n"),
1021                                 lte->staging_file_name);
1022                 break;
1023 #endif
1024         default:
1025                 break;
1026         }
1027         tputc(T('\n'), out);
1028 }
1029
1030 void
1031 lte_to_wimlib_resource_entry(const struct wim_lookup_table_entry *lte,
1032                              struct wimlib_resource_entry *wentry)
1033 {
1034         memset(wentry, 0, sizeof(*wentry));
1035
1036         wentry->uncompressed_size = lte->size;
1037         if (lte->resource_location == RESOURCE_IN_WIM) {
1038                 wentry->part_number = lte->rspec->wim->hdr.part_number;
1039                 if (lte->flags & WIM_RESHDR_FLAG_PACKED_STREAMS) {
1040                         wentry->compressed_size = 0;
1041                         wentry->offset = lte->offset_in_res;
1042                 } else {
1043                         wentry->compressed_size = lte->rspec->size_in_wim;
1044                         wentry->offset = lte->rspec->offset_in_wim;
1045                 }
1046                 wentry->raw_resource_offset_in_wim = lte->rspec->offset_in_wim;
1047                 /*wentry->raw_resource_uncompressed_size = lte->rspec->uncompressed_size;*/
1048                 wentry->raw_resource_compressed_size = lte->rspec->size_in_wim;
1049         }
1050         copy_hash(wentry->sha1_hash, lte->hash);
1051         wentry->reference_count = lte->refcnt;
1052         wentry->is_compressed = (lte->flags & WIM_RESHDR_FLAG_COMPRESSED) != 0;
1053         wentry->is_metadata = (lte->flags & WIM_RESHDR_FLAG_METADATA) != 0;
1054         wentry->is_free = (lte->flags & WIM_RESHDR_FLAG_FREE) != 0;
1055         wentry->is_spanned = (lte->flags & WIM_RESHDR_FLAG_SPANNED) != 0;
1056         wentry->packed = (lte->flags & WIM_RESHDR_FLAG_PACKED_STREAMS) != 0;
1057 }
1058
1059 struct iterate_lte_context {
1060         wimlib_iterate_lookup_table_callback_t cb;
1061         void *user_ctx;
1062 };
1063
1064 static int
1065 do_iterate_lte(struct wim_lookup_table_entry *lte, void *_ctx)
1066 {
1067         struct iterate_lte_context *ctx = _ctx;
1068         struct wimlib_resource_entry entry;
1069
1070         lte_to_wimlib_resource_entry(lte, &entry);
1071         return (*ctx->cb)(&entry, ctx->user_ctx);
1072 }
1073
1074 /* API function documented in wimlib.h  */
1075 WIMLIBAPI int
1076 wimlib_iterate_lookup_table(WIMStruct *wim, int flags,
1077                             wimlib_iterate_lookup_table_callback_t cb,
1078                             void *user_ctx)
1079 {
1080         struct iterate_lte_context ctx = {
1081                 .cb = cb,
1082                 .user_ctx = user_ctx,
1083         };
1084         if (wim->hdr.part_number == 1) {
1085                 int ret;
1086                 for (int i = 0; i < wim->hdr.image_count; i++) {
1087                         ret = do_iterate_lte(wim->image_metadata[i]->metadata_lte,
1088                                              &ctx);
1089                         if (ret)
1090                                 return ret;
1091                 }
1092         }
1093         return for_lookup_table_entry(wim->lookup_table, do_iterate_lte, &ctx);
1094 }
1095
1096 /* Given a SHA1 message digest, return the corresponding entry in the WIM's
1097  * lookup table, or NULL if there is none.  */
1098 struct wim_lookup_table_entry *
1099 lookup_resource(const struct wim_lookup_table *table, const u8 hash[])
1100 {
1101         size_t i;
1102         struct wim_lookup_table_entry *lte;
1103         struct hlist_node *pos;
1104
1105         wimlib_assert(table != NULL);
1106         wimlib_assert(hash != NULL);
1107
1108         i = *(size_t*)hash % table->capacity;
1109         hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
1110                 if (hashes_equal(hash, lte->hash))
1111                         return lte;
1112         return NULL;
1113 }
1114
1115 #ifdef WITH_FUSE
1116 /*
1117  * Finds the dentry, lookup table entry, and stream index for a WIM file stream,
1118  * given a path name.
1119  *
1120  * This is only for pre-resolved inodes.
1121  */
1122 int
1123 wim_pathname_to_stream(WIMStruct *wim,
1124                        const tchar *path,
1125                        int lookup_flags,
1126                        struct wim_dentry **dentry_ret,
1127                        struct wim_lookup_table_entry **lte_ret,
1128                        u16 *stream_idx_ret)
1129 {
1130         struct wim_dentry *dentry;
1131         struct wim_lookup_table_entry *lte;
1132         u16 stream_idx;
1133         const tchar *stream_name = NULL;
1134         struct wim_inode *inode;
1135         tchar *p = NULL;
1136
1137         if (lookup_flags & LOOKUP_FLAG_ADS_OK) {
1138                 stream_name = path_stream_name(path);
1139                 if (stream_name) {
1140                         p = (tchar*)stream_name - 1;
1141                         *p = T('\0');
1142                 }
1143         }
1144
1145         dentry = get_dentry(wim, path);
1146         if (p)
1147                 *p = T(':');
1148         if (!dentry)
1149                 return -errno;
1150
1151         inode = dentry->d_inode;
1152
1153         if (!inode->i_resolved)
1154                 if (inode_resolve_ltes(inode, wim->lookup_table, false))
1155                         return -EIO;
1156
1157         if (!(lookup_flags & LOOKUP_FLAG_DIRECTORY_OK)
1158               && inode_is_directory(inode))
1159                 return -EISDIR;
1160
1161         if (stream_name) {
1162                 struct wim_ads_entry *ads_entry;
1163                 u16 ads_idx;
1164                 ads_entry = inode_get_ads_entry(inode, stream_name,
1165                                                 &ads_idx);
1166                 if (ads_entry) {
1167                         stream_idx = ads_idx + 1;
1168                         lte = ads_entry->lte;
1169                         goto out;
1170                 } else {
1171                         return -ENOENT;
1172                 }
1173         } else {
1174                 lte = inode_unnamed_stream_resolved(inode, &stream_idx);
1175         }
1176 out:
1177         if (dentry_ret)
1178                 *dentry_ret = dentry;
1179         if (lte_ret)
1180                 *lte_ret = lte;
1181         if (stream_idx_ret)
1182                 *stream_idx_ret = stream_idx;
1183         return 0;
1184 }
1185 #endif
1186
1187 int
1188 resource_not_found_error(const struct wim_inode *inode, const u8 *hash)
1189 {
1190         if (wimlib_print_errors) {
1191                 ERROR("\"%"TS"\": resource not found", inode_first_full_path(inode));
1192                 tfprintf(stderr, T("        SHA-1 message digest of missing resource:\n        "));
1193                 print_hash(hash, stderr);
1194                 tputc(T('\n'), stderr);
1195         }
1196         return WIMLIB_ERR_RESOURCE_NOT_FOUND;
1197 }
1198
1199 /*
1200  * Resolve an inode's lookup table entries.
1201  *
1202  * This replaces the SHA1 hash fields (which are used to lookup an entry in the
1203  * lookup table) with pointers directly to the lookup table entries.
1204  *
1205  * If @force is %false:
1206  *      If any needed SHA1 message digests are not found in the lookup table,
1207  *      WIMLIB_ERR_RESOURCE_NOT_FOUND is returned and the inode is left
1208  *      unmodified.
1209  * If @force is %true:
1210  *      If any needed SHA1 message digests are not found in the lookup table,
1211  *      new entries are allocated and inserted into the lookup table.
1212  */
1213 int
1214 inode_resolve_ltes(struct wim_inode *inode, struct wim_lookup_table *table,
1215                    bool force)
1216 {
1217         const u8 *hash;
1218
1219         if (!inode->i_resolved) {
1220                 struct wim_lookup_table_entry *lte, *ads_lte;
1221
1222                 /* Resolve the default file stream */
1223                 lte = NULL;
1224                 hash = inode->i_hash;
1225                 if (!is_zero_hash(hash)) {
1226                         lte = lookup_resource(table, hash);
1227                         if (!lte) {
1228                                 if (force) {
1229                                         lte = new_lookup_table_entry();
1230                                         if (!lte)
1231                                                 return WIMLIB_ERR_NOMEM;
1232                                         copy_hash(lte->hash, hash);
1233                                         lookup_table_insert(table, lte);
1234                                 } else {
1235                                         goto resource_not_found;
1236                                 }
1237                         }
1238                 }
1239
1240                 /* Resolve the alternate data streams */
1241                 struct wim_lookup_table_entry *ads_ltes[inode->i_num_ads];
1242                 for (u16 i = 0; i < inode->i_num_ads; i++) {
1243                         struct wim_ads_entry *cur_entry;
1244
1245                         ads_lte = NULL;
1246                         cur_entry = &inode->i_ads_entries[i];
1247                         hash = cur_entry->hash;
1248                         if (!is_zero_hash(hash)) {
1249                                 ads_lte = lookup_resource(table, hash);
1250                                 if (!ads_lte) {
1251                                         if (force) {
1252                                                 ads_lte = new_lookup_table_entry();
1253                                                 if (!ads_lte)
1254                                                         return WIMLIB_ERR_NOMEM;
1255                                                 copy_hash(ads_lte->hash, hash);
1256                                                 lookup_table_insert(table, ads_lte);
1257                                         } else {
1258                                                 goto resource_not_found;
1259                                         }
1260                                 }
1261                         }
1262                         ads_ltes[i] = ads_lte;
1263                 }
1264                 inode->i_lte = lte;
1265                 for (u16 i = 0; i < inode->i_num_ads; i++)
1266                         inode->i_ads_entries[i].lte = ads_ltes[i];
1267                 inode->i_resolved = 1;
1268         }
1269         return 0;
1270
1271 resource_not_found:
1272         return resource_not_found_error(inode, hash);
1273 }
1274
1275 void
1276 inode_unresolve_ltes(struct wim_inode *inode)
1277 {
1278         if (inode->i_resolved) {
1279                 if (inode->i_lte)
1280                         copy_hash(inode->i_hash, inode->i_lte->hash);
1281                 else
1282                         zero_out_hash(inode->i_hash);
1283
1284                 for (u16 i = 0; i < inode->i_num_ads; i++) {
1285                         if (inode->i_ads_entries[i].lte)
1286                                 copy_hash(inode->i_ads_entries[i].hash,
1287                                           inode->i_ads_entries[i].lte->hash);
1288                         else
1289                                 zero_out_hash(inode->i_ads_entries[i].hash);
1290                 }
1291                 inode->i_resolved = 0;
1292         }
1293 }
1294
1295 /*
1296  * Returns the lookup table entry for stream @stream_idx of the inode, where
1297  * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
1298  * corresponds to an alternate data stream.
1299  *
1300  * This works for both resolved and un-resolved inodes.
1301  */
1302 struct wim_lookup_table_entry *
1303 inode_stream_lte(const struct wim_inode *inode, unsigned stream_idx,
1304                  const struct wim_lookup_table *table)
1305 {
1306         if (inode->i_resolved)
1307                 return inode_stream_lte_resolved(inode, stream_idx);
1308         else
1309                 return inode_stream_lte_unresolved(inode, stream_idx, table);
1310 }
1311
1312 struct wim_lookup_table_entry *
1313 inode_unnamed_stream_resolved(const struct wim_inode *inode, u16 *stream_idx_ret)
1314 {
1315         wimlib_assert(inode->i_resolved);
1316         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1317                 if (inode_stream_name_nbytes(inode, i) == 0 &&
1318                     !is_zero_hash(inode_stream_hash_resolved(inode, i)))
1319                 {
1320                         *stream_idx_ret = i;
1321                         return inode_stream_lte_resolved(inode, i);
1322                 }
1323         }
1324         *stream_idx_ret = 0;
1325         return NULL;
1326 }
1327
1328 struct wim_lookup_table_entry *
1329 inode_unnamed_lte_resolved(const struct wim_inode *inode)
1330 {
1331         u16 stream_idx;
1332         return inode_unnamed_stream_resolved(inode, &stream_idx);
1333 }
1334
1335 struct wim_lookup_table_entry *
1336 inode_unnamed_lte_unresolved(const struct wim_inode *inode,
1337                              const struct wim_lookup_table *table)
1338 {
1339         wimlib_assert(!inode->i_resolved);
1340         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1341                 if (inode_stream_name_nbytes(inode, i) == 0 &&
1342                     !is_zero_hash(inode_stream_hash_unresolved(inode, i)))
1343                 {
1344                         return inode_stream_lte_unresolved(inode, i, table);
1345                 }
1346         }
1347         return NULL;
1348 }
1349
1350 /* Return the lookup table entry for the unnamed data stream of an inode, or
1351  * NULL if there is none.
1352  *
1353  * You'd think this would be easier than it actually is, since the unnamed data
1354  * stream should be the one referenced from the inode itself.  Alas, if there
1355  * are named data streams, Microsoft's "imagex.exe" program will put the unnamed
1356  * data stream in one of the alternate data streams instead of inside the WIM
1357  * dentry itself.  So we need to check the alternate data streams too.
1358  *
1359  * Also, note that a dentry may appear to have more than one unnamed stream, but
1360  * if the SHA1 message digest is all 0's then the corresponding stream does not
1361  * really "count" (this is the case for the inode's own file stream when the
1362  * file stream that should be there is actually in one of the alternate stream
1363  * entries.).  This is despite the fact that we may need to extract such a
1364  * missing entry as an empty file or empty named data stream.
1365  */
1366 struct wim_lookup_table_entry *
1367 inode_unnamed_lte(const struct wim_inode *inode,
1368                   const struct wim_lookup_table *table)
1369 {
1370         if (inode->i_resolved)
1371                 return inode_unnamed_lte_resolved(inode);
1372         else
1373                 return inode_unnamed_lte_unresolved(inode, table);
1374 }
1375
1376 /* Returns the SHA1 message digest of the unnamed data stream of a WIM inode, or
1377  * 'zero_hash' if the unnamed data stream is missing has all zeroes in its SHA1
1378  * message digest field.  */
1379 const u8 *
1380 inode_unnamed_stream_hash(const struct wim_inode *inode)
1381 {
1382         const u8 *hash;
1383
1384         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1385                 if (inode_stream_name_nbytes(inode, i) == 0) {
1386                         hash = inode_stream_hash(inode, i);
1387                         if (!is_zero_hash(hash))
1388                                 return hash;
1389                 }
1390         }
1391         return zero_hash;
1392 }
1393
1394 struct wim_lookup_table_entry **
1395 retrieve_lte_pointer(struct wim_lookup_table_entry *lte)
1396 {
1397         wimlib_assert(lte->unhashed);
1398         struct wim_inode *inode = lte->back_inode;
1399         u32 stream_id = lte->back_stream_id;
1400         if (stream_id == 0)
1401                 return &inode->i_lte;
1402         else
1403                 for (u16 i = 0; i < inode->i_num_ads; i++)
1404                         if (inode->i_ads_entries[i].stream_id == stream_id)
1405                                 return &inode->i_ads_entries[i].lte;
1406         wimlib_assert(0);
1407         return NULL;
1408 }
1409
1410 /* Calculate the SHA1 message digest of a stream and move it from the list of
1411  * unhashed streams to the stream lookup table, possibly joining it with an
1412  * existing lookup table entry for an identical stream.
1413  *
1414  * @lte:  An unhashed lookup table entry.
1415  * @lookup_table:  Lookup table for the WIM.
1416  * @lte_ret:  On success, write a pointer to the resulting lookup table
1417  *            entry to this location.  This will be the same as @lte
1418  *            if it was inserted into the lookup table, or different if
1419  *            a duplicate stream was found.
1420  *
1421  * Returns 0 on success; nonzero if there is an error reading the stream.
1422  */
1423 int
1424 hash_unhashed_stream(struct wim_lookup_table_entry *lte,
1425                      struct wim_lookup_table *lookup_table,
1426                      struct wim_lookup_table_entry **lte_ret)
1427 {
1428         int ret;
1429         struct wim_lookup_table_entry *duplicate_lte;
1430         struct wim_lookup_table_entry **back_ptr;
1431
1432         wimlib_assert(lte->unhashed);
1433
1434         /* back_ptr must be saved because @back_inode and @back_stream_id are in
1435          * union with the SHA1 message digest and will no longer be valid once
1436          * the SHA1 has been calculated. */
1437         back_ptr = retrieve_lte_pointer(lte);
1438
1439         ret = sha1_stream(lte);
1440         if (ret)
1441                 return ret;
1442
1443         /* Look for a duplicate stream */
1444         duplicate_lte = lookup_resource(lookup_table, lte->hash);
1445         list_del(&lte->unhashed_list);
1446         if (duplicate_lte) {
1447                 /* We have a duplicate stream.  Transfer the reference counts
1448                  * from this stream to the duplicate and update the reference to
1449                  * this stream (in an inode or ads_entry) to point to the
1450                  * duplicate.  The caller is responsible for freeing @lte if
1451                  * needed.  */
1452                 wimlib_assert(!(duplicate_lte->unhashed));
1453                 wimlib_assert(duplicate_lte->size == lte->size);
1454                 duplicate_lte->refcnt += lte->refcnt;
1455                 lte->refcnt = 0;
1456                 *back_ptr = duplicate_lte;
1457                 lte = duplicate_lte;
1458         } else {
1459                 /* No duplicate stream, so we need to insert this stream into
1460                  * the lookup table and treat it as a hashed stream. */
1461                 lookup_table_insert(lookup_table, lte);
1462                 lte->unhashed = 0;
1463         }
1464         *lte_ret = lte;
1465         return 0;
1466 }
1467
1468 static int
1469 lte_clone_if_new(struct wim_lookup_table_entry *lte, void *_lookup_table)
1470 {
1471         struct wim_lookup_table *lookup_table = _lookup_table;
1472
1473         if (lookup_resource(lookup_table, lte->hash))
1474                 return 0;  /*  Resource already present.  */
1475
1476         lte = clone_lookup_table_entry(lte);
1477         if (lte == NULL)
1478                 return WIMLIB_ERR_NOMEM;
1479         lte->out_refcnt = 1;
1480         lookup_table_insert(lookup_table, lte);
1481         return 0;
1482 }
1483
1484 static int
1485 lte_delete_if_new(struct wim_lookup_table_entry *lte, void *_lookup_table)
1486 {
1487         struct wim_lookup_table *lookup_table = _lookup_table;
1488
1489         if (lte->out_refcnt) {
1490                 lookup_table_unlink(lookup_table, lte);
1491                 free_lookup_table_entry(lte);
1492         }
1493         return 0;
1494 }
1495
1496 /* API function documented in wimlib.h  */
1497 WIMLIBAPI int
1498 wimlib_reference_resources(WIMStruct *wim,
1499                            WIMStruct **resource_wims, unsigned num_resource_wims,
1500                            int ref_flags)
1501 {
1502         int ret;
1503         unsigned i;
1504
1505         if (wim == NULL)
1506                 return WIMLIB_ERR_INVALID_PARAM;
1507
1508         if (num_resource_wims != 0 && resource_wims == NULL)
1509                 return WIMLIB_ERR_INVALID_PARAM;
1510
1511         for (i = 0; i < num_resource_wims; i++)
1512                 if (resource_wims[i] == NULL)
1513                         return WIMLIB_ERR_INVALID_PARAM;
1514
1515         for_lookup_table_entry(wim->lookup_table, lte_zero_out_refcnt, NULL);
1516
1517         for (i = 0; i < num_resource_wims; i++) {
1518                 ret = for_lookup_table_entry(resource_wims[i]->lookup_table,
1519                                              lte_clone_if_new,
1520                                              wim->lookup_table);
1521                 if (ret)
1522                         goto out_rollback;
1523         }
1524         return 0;
1525
1526 out_rollback:
1527         for_lookup_table_entry(wim->lookup_table, lte_delete_if_new,
1528                                wim->lookup_table);
1529         return ret;
1530 }
1531
1532 static int
1533 reference_resource_paths(WIMStruct *wim,
1534                          const tchar * const *resource_wimfiles,
1535                          unsigned num_resource_wimfiles,
1536                          int ref_flags,
1537                          int open_flags,
1538                          wimlib_progress_func_t progress_func)
1539 {
1540         WIMStruct **resource_wims;
1541         unsigned i;
1542         int ret;
1543
1544         resource_wims = CALLOC(num_resource_wimfiles, sizeof(resource_wims[0]));
1545         if (!resource_wims)
1546                 return WIMLIB_ERR_NOMEM;
1547
1548         for (i = 0; i < num_resource_wimfiles; i++) {
1549                 DEBUG("Referencing resources from path \"%"TS"\"",
1550                       resource_wimfiles[i]);
1551                 ret = wimlib_open_wim(resource_wimfiles[i], open_flags,
1552                                       &resource_wims[i], progress_func);
1553                 if (ret)
1554                         goto out_free_resource_wims;
1555         }
1556
1557         ret = wimlib_reference_resources(wim, resource_wims,
1558                                          num_resource_wimfiles, ref_flags);
1559         if (ret)
1560                 goto out_free_resource_wims;
1561
1562         for (i = 0; i < num_resource_wimfiles; i++)
1563                 list_add_tail(&resource_wims[i]->subwim_node, &wim->subwims);
1564
1565         ret = 0;
1566         goto out_free_array;
1567
1568 out_free_resource_wims:
1569         for (i = 0; i < num_resource_wimfiles; i++)
1570                 wimlib_free(resource_wims[i]);
1571 out_free_array:
1572         FREE(resource_wims);
1573         return ret;
1574 }
1575
1576 static int
1577 reference_resource_glob(WIMStruct *wim, const tchar *refglob,
1578                         int ref_flags, int open_flags,
1579                         wimlib_progress_func_t progress_func)
1580 {
1581         glob_t globbuf;
1582         int ret;
1583
1584         /* Note: glob() is replaced in Windows native builds.  */
1585         ret = tglob(refglob, GLOB_ERR | GLOB_NOSORT, NULL, &globbuf);
1586         if (ret) {
1587                 if (ret == GLOB_NOMATCH) {
1588                         if (ref_flags & WIMLIB_REF_FLAG_GLOB_ERR_ON_NOMATCH) {
1589                                 ERROR("Found no files for glob \"%"TS"\"", refglob);
1590                                 return WIMLIB_ERR_GLOB_HAD_NO_MATCHES;
1591                         } else {
1592                                 return reference_resource_paths(wim,
1593                                                                 &refglob,
1594                                                                 1,
1595                                                                 ref_flags,
1596                                                                 open_flags,
1597                                                                 progress_func);
1598                         }
1599                 } else {
1600                         ERROR_WITH_ERRNO("Failed to process glob \"%"TS"\"", refglob);
1601                         if (ret == GLOB_NOSPACE)
1602                                 return WIMLIB_ERR_NOMEM;
1603                         else
1604                                 return WIMLIB_ERR_READ;
1605                 }
1606         }
1607
1608         ret = reference_resource_paths(wim,
1609                                        (const tchar * const *)globbuf.gl_pathv,
1610                                        globbuf.gl_pathc,
1611                                        ref_flags,
1612                                        open_flags,
1613                                        progress_func);
1614         globfree(&globbuf);
1615         return ret;
1616 }
1617
1618 /* API function documented in wimlib.h  */
1619 WIMLIBAPI int
1620 wimlib_reference_resource_files(WIMStruct *wim,
1621                                 const tchar * const * resource_wimfiles_or_globs,
1622                                 unsigned count,
1623                                 int ref_flags,
1624                                 int open_flags,
1625                                 wimlib_progress_func_t progress_func)
1626 {
1627         unsigned i;
1628         int ret;
1629
1630         if (ref_flags & WIMLIB_REF_FLAG_GLOB_ENABLE) {
1631                 for (i = 0; i < count; i++) {
1632                         ret = reference_resource_glob(wim,
1633                                                       resource_wimfiles_or_globs[i],
1634                                                       ref_flags,
1635                                                       open_flags,
1636                                                       progress_func);
1637                         if (ret)
1638                                 return ret;
1639                 }
1640                 return 0;
1641         } else {
1642                 return reference_resource_paths(wim, resource_wimfiles_or_globs,
1643                                                 count, ref_flags,
1644                                                 open_flags, progress_func);
1645         }
1646 }