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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)
  95                 return NULL;
  96
  97         new->extracted_file = NULL;
  98         switch (new->resource_location) {
  99         case RESOURCE_IN_WIM:
 100                 list_add(&new->wim_resource_list, &new->rspec->lte_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)
 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)
 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)
 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)
 133                                 goto out_free;
 134                         if (loc->stream_name_nchars) {
 135                                 loc->stream_name = memdup(old->ntfs_loc->stream_name,
 136                                                           loc->stream_name_nchars * 2);
 137                                 if (!loc->stream_name)
 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->wim_resource_list);
 159                         if (list_empty(&lte->rspec->lte_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         DEBUG2("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 and writing.
 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         u64 offset1, offset2;
 314
 315         lte1 = *(const struct wim_lookup_table_entry**)p1;
 316         lte2 = *(const struct wim_lookup_table_entry**)p2;
 317
 318         v = (int)lte1->resource_location - (int)lte2->resource_location;
 319
 320         /* Different resource locations?  */
 321         if (v)
 322                 return v;
 323
 324         switch (lte1->resource_location) {
 325         case RESOURCE_IN_WIM:
 326                 wim1 = lte1->rspec->wim;
 327                 wim2 = lte2->rspec->wim;
 328
 329                 /* Different (possibly split) WIMs?  */
 330                 if (wim1 != wim2) {
 331                         v = memcmp(wim1->hdr.guid, wim2->hdr.guid, WIM_GID_LEN);
 332                         if (v)
 333                                 return v;
 334                 }
 335
 336                 /* Different part numbers in the same WIM?  */
 337                 v = (int)wim1->hdr.part_number - (int)wim2->hdr.part_number;
 338                 if (v)
 339                         return v;
 340
 341                 /* Compare by offset.  */
 342                 offset1 = lte1->rspec->offset_in_wim + lte1->offset_in_res;
 343                 offset2 = lte2->rspec->offset_in_wim + lte2->offset_in_res;
 344
 345                 if (offset1 < offset2)
 346                         return -1;
 347                 if (offset1 > offset2)
 348                         return 1;
 349                 return 0;
 350         case RESOURCE_IN_FILE_ON_DISK:
 351 #ifdef WITH_FUSE
 352         case RESOURCE_IN_STAGING_FILE:
 353 #endif
 354 #ifdef __WIN32__
 355         case RESOURCE_WIN32_ENCRYPTED:
 356 #endif
 357                 /* Compare files by path: just a heuristic that will place files
 358                  * in the same directory next to each other.  */
 359                 return tstrcmp(lte1->file_on_disk, lte2->file_on_disk);
 360 #ifdef WITH_NTFS_3G
 361         case RESOURCE_IN_NTFS_VOLUME:
 362                 return tstrcmp(lte1->ntfs_loc->path, lte2->ntfs_loc->path);
 363 #endif
 364         default:
 365                 /* No additional sorting order defined for this resource
 366                  * location (e.g. RESOURCE_IN_ATTACHED_BUFFER); simply compare
 367                  * everything equal to each other.  */
 368                 return 0;
 369         }
 370 }
 371
 372 int
 373 sort_stream_list_by_sequential_order(struct list_head *stream_list,
 374                                      size_t list_head_offset)
 375 {
 376         struct list_head *cur;
 377         struct wim_lookup_table_entry **array;
 378         size_t i;
 379         size_t array_size;
 380         size_t num_streams = 0;
 381
 382         list_for_each(cur, stream_list)
 383                 num_streams++;
 384
 385         array_size = num_streams * sizeof(array[0]);
 386         array = MALLOC(array_size);
 387         if (array == NULL)
 388                 return WIMLIB_ERR_NOMEM;
 389         cur = stream_list->next;
 390         for (i = 0; i < num_streams; i++) {
 391                 array[i] = (struct wim_lookup_table_entry*)((u8*)cur -
 392                                                             list_head_offset);
 393                 cur = cur->next;
 394         }
 395
 396         qsort(array, num_streams, sizeof(array[0]),
 397               cmp_streams_by_sequential_order);
 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
 410 static int
 411 add_lte_to_array(struct wim_lookup_table_entry *lte,
 412                  void *_pp)
 413 {
 414         struct wim_lookup_table_entry ***pp = _pp;
 415         *(*pp)++ = lte;
 416         return 0;
 417 }
 418
 419 /* Iterate through the lookup table entries, but first sort them by stream
 420  * offset in the WIM.  Caution: this is intended to be used when the stream
 421  * offset field has actually been set. */
 422 int
 423 for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
 424                                   int (*visitor)(struct wim_lookup_table_entry *,
 425                                                  void *),
 426                                   void *arg)
 427 {
 428         struct wim_lookup_table_entry **lte_array, **p;
 429         size_t num_streams = table->num_entries;
 430         int ret;
 431
 432         lte_array = MALLOC(num_streams * sizeof(lte_array[0]));
 433         if (!lte_array)
 434                 return WIMLIB_ERR_NOMEM;
 435         p = lte_array;
 436         for_lookup_table_entry(table, add_lte_to_array, &p);
 437
 438         wimlib_assert(p == lte_array + num_streams);
 439
 440         qsort(lte_array, num_streams, sizeof(lte_array[0]),
 441               cmp_streams_by_sequential_order);
 442         ret = 0;
 443         for (size_t i = 0; i < num_streams; i++) {
 444                 ret = visitor(lte_array[i], arg);
 445                 if (ret)
 446                         break;
 447         }
 448         FREE(lte_array);
 449         return ret;
 450 }
 451
 452 /* On-disk format of a WIM lookup table entry (stream entry). */
 453 struct wim_lookup_table_entry_disk {
 454         /* Size, offset, and flags of the stream.  */
 455         struct wim_reshdr_disk reshdr;
 456
 457         /* Which part of the split WIM this stream is in; indexed from 1. */
 458         le16 part_number;
 459
 460         /* Reference count of this stream over all WIM images. */
 461         le32 refcnt;
 462
 463         /* SHA1 message digest of the uncompressed data of this stream, or
 464          * optionally all zeroes if this stream is of zero length. */
 465         u8 hash[SHA1_HASH_SIZE];
 466 } _packed_attribute;
 467
 468 #define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
 469
 470 static int
 471 validate_resource(const struct wim_resource_spec *rspec)
 472 {
 473         struct wim_lookup_table_entry *lte;
 474         if (!list_is_singular(&rspec->lte_list)) {
 475                 list_for_each_entry(lte, &rspec->lte_list, wim_resource_list) {
 476                         if (rspec->flags & WIM_RESHDR_FLAG_COMPRESSED)
 477                                 lte->flags |= WIM_RESHDR_FLAG_COMPRESSED;
 478                         else
 479                                 lte->flags &= ~WIM_RESHDR_FLAG_COMPRESSED;
 480
 481                         if (lte->offset_in_res + lte->size < lte->size ||
 482                             lte->offset_in_res + lte->size > rspec->uncompressed_size)
 483                         {
 484                                 return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 485                         }
 486                 }
 487         }
 488         return 0;
 489 }
 490
 491 /*
 492  * Reads the lookup table from a WIM file.
 493  *
 494  * Saves lookup table entries for non-metadata streams in a hash table, and
 495  * saves the metadata entry for each image in a special per-image location (the
 496  * image_metadata array).
 497  *
 498  * Return values:
 499  *      WIMLIB_ERR_SUCCESS (0)
 500  *      WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY
 501  *      WIMLIB_ERR_RESOURCE_NOT_FOUND
 502  */
 503 int
 504 read_wim_lookup_table(WIMStruct *wim)
 505 {
 506         int ret;
 507         size_t i;
 508         size_t num_entries;
 509         struct wim_lookup_table *table;
 510         struct wim_lookup_table_entry *cur_entry, *duplicate_entry;
 511         struct wim_resource_spec *cur_rspec;
 512         void *buf;
 513
 514         BUILD_BUG_ON(sizeof(struct wim_lookup_table_entry_disk) !=
 515                      WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE);
 516
 517         DEBUG("Reading lookup table.");
 518
 519         /* Calculate number of entries in the lookup table.  */
 520         num_entries = wim->hdr.lookup_table_reshdr.uncompressed_size /
 521                       sizeof(struct wim_lookup_table_entry_disk);
 522
 523         /* Read the lookup table into a buffer.  */
 524         ret = wim_reshdr_to_data(&wim->hdr.lookup_table_reshdr, wim, &buf);
 525         if (ret)
 526                 goto out;
 527
 528         /* Allocate hash table.  */
 529         table = new_lookup_table(num_entries * 2 + 1);
 530         if (table == NULL) {
 531                 ERROR("Not enough memory to read lookup table.");
 532                 ret = WIMLIB_ERR_NOMEM;
 533                 goto out_free_buf;
 534         }
 535
 536         /* Allocate and initalize `struct wim_lookup_table_entry's from the
 537          * on-disk lookup table.  */
 538         wim->current_image = 0;
 539         cur_rspec = NULL;
 540         for (i = 0; i < num_entries; i++) {
 541                 const struct wim_lookup_table_entry_disk *disk_entry =
 542                         &((const struct wim_lookup_table_entry_disk*)buf)[i];
 543                 u16 part_number;
 544                 struct wim_reshdr reshdr;
 545
 546                 ret = get_wim_reshdr(&disk_entry->reshdr, &reshdr);
 547                 if (ret) {
 548                         ERROR("Resource header is invalid!");
 549                         goto out_free_lookup_table;
 550                 }
 551
 552                 DEBUG("reshdr: size_in_wim=%"PRIu64", "
 553                       "uncompressed_size=%"PRIu64", "
 554                       "offset_in_wim=%"PRIu64", "
 555                       "flags=0x%02x",
 556                       reshdr.size_in_wim, reshdr.uncompressed_size,
 557                       reshdr.offset_in_wim, reshdr.flags);
 558
 559                 cur_entry = new_lookup_table_entry();
 560                 if (cur_entry == NULL) {
 561                         ERROR("Not enough memory to read lookup table!");
 562                         ret = WIMLIB_ERR_NOMEM;
 563                         goto out_free_lookup_table;
 564                 }
 565
 566                 part_number = le16_to_cpu(disk_entry->part_number);
 567                 cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
 568                 copy_hash(cur_entry->hash, disk_entry->hash);
 569
 570                 if (part_number != wim->hdr.part_number) {
 571                         WARNING("A lookup table entry in part %hu of the WIM "
 572                                 "points to part %hu (ignoring it)",
 573                                 wim->hdr.part_number, part_number);
 574                         free_lookup_table_entry(cur_entry);
 575                         continue;
 576                 }
 577
 578                 if (cur_rspec == NULL ||
 579                     !(reshdr.flags & WIM_RESHDR_FLAG_CONCAT))
 580                 {
 581                         /* Starting new run of stream entries that all share the
 582                          * same WIM resource (streams concatenated together); or
 583                          * simply a single normal entry by itself.  */
 584
 585                         if (cur_rspec != NULL) {
 586                                 ret = validate_resource(cur_rspec);
 587                                 if (ret)
 588                                         goto out_free_cur_entry;
 589                         }
 590
 591                         cur_rspec = MALLOC(sizeof(struct wim_resource_spec));
 592                         if (cur_rspec == NULL) {
 593                                 ERROR("Not enough memory to read lookup table!");
 594                                 ret = WIMLIB_ERR_NOMEM;
 595                                 goto out_free_cur_entry;
 596                         }
 597                         wim_res_hdr_to_spec(&reshdr, wim, cur_rspec);
 598                         if (reshdr.flags & WIM_RESHDR_FLAG_CONCAT) {
 599                                 cur_rspec->size_in_wim = 0;
 600                                 cur_rspec->uncompressed_size = 0;
 601                         }
 602                 } else if (is_zero_hash(cur_entry->hash)) {
 603                         /* Found the resource specification for the run.  */
 604                         cur_rspec->offset_in_wim = reshdr.offset_in_wim;
 605                         cur_rspec->size_in_wim = reshdr.size_in_wim;
 606                         cur_rspec->flags = reshdr.flags;
 607                         DEBUG("Full run is %"PRIu64" compressed bytes "
 608                               "at file offset %"PRIu64" (flags 0x%02x)",
 609                               cur_rspec->size_in_wim,
 610                               cur_rspec->offset_in_wim,
 611                               cur_rspec->flags);
 612                         free_lookup_table_entry(cur_entry);
 613                         continue;
 614                 }
 615
 616                 if (reshdr.flags & WIM_RESHDR_FLAG_CONCAT) {
 617                         /* Continuing the run with another stream.  */
 618                         DEBUG("Continuing concat run with stream: "
 619                               "%"PRIu64" uncompressed bytes @ resource offset %"PRIu64")",
 620                               reshdr.size_in_wim, reshdr.offset_in_wim);
 621                         cur_rspec->uncompressed_size += reshdr.size_in_wim;
 622                 }
 623
 624                 lte_bind_wim_resource_spec(cur_entry, cur_rspec);
 625                 if (reshdr.flags & WIM_RESHDR_FLAG_CONCAT) {
 626                         /* In concatenation runs, the offset field is used for
 627                          * in-resource offset, not the in-WIM offset, and the
 628                          * size field is used for the uncompressed size, not the
 629                          * compressed size.  */
 630                         cur_entry->offset_in_res = reshdr.offset_in_wim;
 631                         cur_entry->size = reshdr.size_in_wim;
 632                         cur_entry->flags = reshdr.flags;
 633                 } else {
 634                         cur_entry->offset_in_res = 0;
 635                         cur_entry->size = reshdr.uncompressed_size;
 636                         cur_entry->flags = reshdr.flags;
 637                         cur_rspec = NULL;
 638                 }
 639
 640                 if (is_zero_hash(cur_entry->hash)) {
 641                         WARNING("The WIM lookup table contains an entry with a "
 642                                 "SHA1 message digest of all 0's (ignoring it)");
 643                         free_lookup_table_entry(cur_entry);
 644                         continue;
 645                 }
 646
 647                 if (cur_entry->flags & WIM_RESHDR_FLAG_METADATA) {
 648                         /* Lookup table entry for a metadata resource */
 649                         if (cur_entry->refcnt != 1) {
 650                                 /* Metadata entries with no references must be
 651                                  * ignored.  See for example the WinPE WIMs from
 652                                  * WAIK v2.1.  */
 653                                 if (cur_entry->refcnt == 0) {
 654                                         free_lookup_table_entry(cur_entry);
 655                                         continue;
 656                                 }
 657                                 if (wimlib_print_errors) {
 658                                         ERROR("Found metadata resource with refcnt != 1:");
 659                                         print_lookup_table_entry(cur_entry, stderr);
 660                                 }
 661                                 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 662                                 goto out_free_cur_entry;
 663                         }
 664
 665                         if (wim->hdr.part_number != 1) {
 666                                 WARNING("Ignoring metadata resource found in a "
 667                                         "non-first part of the split WIM");
 668                                 free_lookup_table_entry(cur_entry);
 669                                 continue;
 670                         }
 671                         if (wim->current_image == wim->hdr.image_count) {
 672                                 WARNING("The WIM header says there are %u images "
 673                                         "in the WIM, but we found more metadata "
 674                                         "resources than this (ignoring the extra)",
 675                                         wim->hdr.image_count);
 676                                 free_lookup_table_entry(cur_entry);
 677                                 continue;
 678                         }
 679
 680                         /* Notice very carefully:  We are assigning the metadata
 681                          * resources in the exact order mirrored by their lookup
 682                          * table entries on disk, which is the behavior of
 683                          * Microsoft's software.  In particular, this overrides
 684                          * the actual locations of the metadata resources
 685                          * themselves in the WIM file as well as any information
 686                          * written in the XML data. */
 687                         DEBUG("Found metadata resource for image %u at "
 688                               "offset %"PRIu64".",
 689                               wim->current_image + 1,
 690                               cur_entry->rspec->offset_in_wim);
 691                         wim->image_metadata[
 692                                 wim->current_image++]->metadata_lte = cur_entry;
 693                 } else {
 694                         /* Lookup table entry for a stream that is not a
 695                          * metadata resource */
 696                         duplicate_entry = lookup_resource(table, cur_entry->hash);
 697                         if (duplicate_entry) {
 698                                 if (wimlib_print_errors) {
 699                                         WARNING("The WIM lookup table contains two entries with the "
 700                                               "same SHA1 message digest!");
 701                                         WARNING("The first entry is:");
 702                                         print_lookup_table_entry(duplicate_entry, stderr);
 703                                         WARNING("The second entry is:");
 704                                         print_lookup_table_entry(cur_entry, stderr);
 705                                 }
 706                                 free_lookup_table_entry(cur_entry);
 707                                 continue;
 708                         } else {
 709                                 lookup_table_insert(table, cur_entry);
 710                         }
 711                 }
 712         }
 713
 714         if (cur_rspec != NULL) {
 715                 ret = validate_resource(cur_rspec);
 716                 if (ret)
 717                         goto out_free_cur_entry;
 718         }
 719
 720         if (wim->hdr.part_number == 1 && wim->current_image != wim->hdr.image_count) {
 721                 WARNING("The header of \"%"TS"\" says there are %u images in\n"
 722                         "          the WIM, but we only found %d metadata resources!  Acting as if\n"
 723                         "          the header specified only %d images instead.",
 724                         wim->filename, wim->hdr.image_count,
 725                         wim->current_image, wim->current_image);
 726                 for (int i = wim->current_image; i < wim->hdr.image_count; i++)
 727                         put_image_metadata(wim->image_metadata[i], NULL);
 728                 wim->hdr.image_count = wim->current_image;
 729         }
 730         DEBUG("Done reading lookup table.");
 731         wim->lookup_table = table;
 732         ret = 0;
 733         goto out_free_buf;
 734
 735 out_free_cur_entry:
 736         FREE(cur_entry);
 737 out_free_lookup_table:
 738         free_lookup_table(table);
 739 out_free_buf:
 740         FREE(buf);
 741 out:
 742         wim->current_image = 0;
 743         return ret;
 744 }
 745
 746
 747 static void
 748 write_wim_lookup_table_entry(const struct wim_lookup_table_entry *lte,
 749                              struct wim_lookup_table_entry_disk *disk_entry,
 750                              u16 part_number)
 751 {
 752         put_wim_reshdr(&lte->out_reshdr, &disk_entry->reshdr);
 753         disk_entry->part_number = cpu_to_le16(part_number);
 754         disk_entry->refcnt = cpu_to_le32(lte->out_refcnt);
 755         copy_hash(disk_entry->hash, lte->hash);
 756 }
 757
 758 static int
 759 write_wim_lookup_table_from_stream_list(struct list_head *stream_list,
 760                                         struct filedes *out_fd,
 761                                         u16 part_number,
 762                                         struct wim_reshdr *out_reshdr,
 763                                         int write_resource_flags,
 764                                         struct wimlib_lzx_context **comp_ctx)
 765 {
 766         size_t table_size;
 767         struct wim_lookup_table_entry *lte;
 768         struct wim_lookup_table_entry_disk *table_buf;
 769         struct wim_lookup_table_entry_disk *table_buf_ptr;
 770         int ret;
 771
 772         table_size = 0;
 773         list_for_each_entry(lte, stream_list, lookup_table_list)
 774                 table_size += sizeof(struct wim_lookup_table_entry_disk);
 775
 776         DEBUG("Writing WIM lookup table (size=%zu, offset=%"PRIu64")",
 777               table_size, out_fd->offset);
 778
 779         table_buf = MALLOC(table_size);
 780         if (!table_buf) {
 781                 ERROR("Failed to allocate %zu bytes for temporary lookup table",
 782                       table_size);
 783                 return WIMLIB_ERR_NOMEM;
 784         }
 785         table_buf_ptr = table_buf;
 786         list_for_each_entry(lte, stream_list, lookup_table_list)
 787                 write_wim_lookup_table_entry(lte, table_buf_ptr++, part_number);
 788
 789         /* Write the lookup table uncompressed.  Although wimlib can handle a
 790          * compressed lookup table, MS software cannot.  */
 791         ret = write_wim_resource_from_buffer(table_buf,
 792                                              table_size,
 793                                              WIM_RESHDR_FLAG_METADATA,
 794                                              out_fd,
 795                                              WIMLIB_COMPRESSION_TYPE_NONE,
 796                                              0,
 797                                              out_reshdr,
 798                                              NULL,
 799                                              write_resource_flags,
 800                                              comp_ctx);
 801         FREE(table_buf);
 802         DEBUG("ret=%d", ret);
 803         return ret;
 804 }
 805
 806 static int
 807 append_lookup_table_entry(struct wim_lookup_table_entry *lte, void *_list)
 808 {
 809         /* Lookup table entries with 'out_refcnt' == 0 correspond to streams not
 810          * written and not present in the resulting WIM file, and should not be
 811          * included in the lookup table.
 812          *
 813          * Lookup table entries marked as filtered (EXTERNAL_WIM) with
 814          * 'out_refcnt != 0' were referenced as part of the logical write but
 815          * correspond to streams that were not in fact written, and should not
 816          * be included in the lookup table.
 817          *
 818          * Lookup table entries marked as filtered (SAME_WIM) with 'out_refcnt
 819          * != 0' were referenced as part of the logical write but correspond to
 820          * streams that were not in fact written, but nevertheless were already
 821          * present in the WIM being overwritten in-place.  These entries must be
 822          * included in the lookup table, and the resource information to write
 823          * needs to be copied from the resource information read originally.
 824          */
 825         if (lte->out_refcnt != 0 && !(lte->filtered & FILTERED_EXTERNAL_WIM)) {
 826                 if (lte->filtered & FILTERED_SAME_WIM)
 827                         wim_res_spec_to_hdr(lte->rspec, &lte->out_reshdr);
 828                 list_add_tail(&lte->lookup_table_list, (struct list_head*)_list);
 829         }
 830         return 0;
 831 }
 832
 833 int
 834 write_wim_lookup_table(WIMStruct *wim, int image, int write_flags,
 835                        struct wim_reshdr *out_reshdr,
 836                        struct list_head *stream_list_override)
 837 {
 838         int write_resource_flags;
 839         struct list_head _stream_list;
 840         struct list_head *stream_list;
 841
 842         if (stream_list_override) {
 843                 stream_list = stream_list_override;
 844         } else {
 845                 stream_list = &_stream_list;
 846                 INIT_LIST_HEAD(stream_list);
 847         }
 848
 849         if (!(write_flags & WIMLIB_WRITE_FLAG_NO_METADATA)) {
 850                 int start_image;
 851                 int end_image;
 852
 853                 if (image == WIMLIB_ALL_IMAGES) {
 854                         start_image = 1;
 855                         end_image = wim->hdr.image_count;
 856                 } else {
 857                         start_image = image;
 858                         end_image = image;
 859                 }
 860
 861                 /* Push metadata resource lookup table entries onto the front of
 862                  * the list in reverse order, so that they're written in order.
 863                  */
 864                 for (int i = end_image; i >= start_image; i--) {
 865                         struct wim_lookup_table_entry *metadata_lte;
 866
 867                         metadata_lte = wim->image_metadata[i - 1]->metadata_lte;
 868                         metadata_lte->out_refcnt = 1;
 869                         metadata_lte->out_reshdr.flags |= WIM_RESHDR_FLAG_METADATA;
 870                         list_add(&metadata_lte->lookup_table_list, stream_list);
 871                 }
 872         }
 873
 874         /* Append additional lookup table entries that need to be written, with
 875          * some special handling for streams that have been marked as filtered.
 876          */
 877         if (!stream_list_override) {
 878                 for_lookup_table_entry(wim->lookup_table,
 879                                        append_lookup_table_entry, stream_list);
 880         }
 881
 882         write_resource_flags = 0;
 883         if (write_flags & WIMLIB_WRITE_FLAG_PIPABLE)
 884                 write_resource_flags |= WIMLIB_WRITE_RESOURCE_FLAG_PIPABLE;
 885         return write_wim_lookup_table_from_stream_list(stream_list,
 886                                                        &wim->out_fd,
 887                                                        wim->hdr.part_number,
 888                                                        out_reshdr,
 889                                                        write_resource_flags,
 890                                                        &wim->lzx_context);
 891 }
 892
 893
 894 int
 895 lte_zero_real_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
 896 {
 897         lte->real_refcnt = 0;
 898         return 0;
 899 }
 900
 901 int
 902 lte_zero_out_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
 903 {
 904         lte->out_refcnt = 0;
 905         return 0;
 906 }
 907
 908 int
 909 lte_free_extracted_file(struct wim_lookup_table_entry *lte, void *_ignore)
 910 {
 911         if (lte->extracted_file != NULL) {
 912                 FREE(lte->extracted_file);
 913                 lte->extracted_file = NULL;
 914         }
 915         return 0;
 916 }
 917
 918 void
 919 print_lookup_table_entry(const struct wim_lookup_table_entry *lte, FILE *out)
 920 {
 921         if (lte == NULL) {
 922                 tputc(T('\n'), out);
 923                 return;
 924         }
 925
 926
 927         tprintf(T("Uncompressed size     = %"PRIu64" bytes\n"),
 928                 lte->size);
 929         if (lte_is_partial(lte)) {
 930                 tprintf(T("Offset                = %"PRIu64" bytes\n"),
 931                         lte->offset_in_res);
 932
 933                 tprintf(T("Raw uncompressed size = %"PRIu64" bytes\n"),
 934                         lte->rspec->uncompressed_size);
 935
 936                 tprintf(T("Raw compressed size   = %"PRIu64" bytes\n"),
 937                         lte->rspec->size_in_wim);
 938
 939                 tprintf(T("Raw offset            = %"PRIu64" bytes\n"),
 940                         lte->rspec->offset_in_wim);
 941         } else if (lte->resource_location == RESOURCE_IN_WIM) {
 942                 tprintf(T("Compressed size       = %"PRIu64" bytes\n"),
 943                         lte->rspec->size_in_wim);
 944
 945                 tprintf(T("Offset                = %"PRIu64" bytes\n"),
 946                         lte->rspec->offset_in_wim);
 947         }
 948
 949         tfprintf(out, T("Reference Count       = %u\n"), lte->refcnt);
 950
 951         if (lte->unhashed) {
 952                 tfprintf(out, T("(Unhashed: inode %p, stream_id = %u)\n"),
 953                          lte->back_inode, lte->back_stream_id);
 954         } else {
 955                 tfprintf(out, T("Hash                  = 0x"));
 956                 print_hash(lte->hash, out);
 957                 tputc(T('\n'), out);
 958         }
 959
 960         tfprintf(out, T("Flags                 = "));
 961         u8 flags = lte->flags;
 962         if (flags & WIM_RESHDR_FLAG_COMPRESSED)
 963                 tfputs(T("WIM_RESHDR_FLAG_COMPRESSED, "), out);
 964         if (flags & WIM_RESHDR_FLAG_FREE)
 965                 tfputs(T("WIM_RESHDR_FLAG_FREE, "), out);
 966         if (flags & WIM_RESHDR_FLAG_METADATA)
 967                 tfputs(T("WIM_RESHDR_FLAG_METADATA, "), out);
 968         if (flags & WIM_RESHDR_FLAG_SPANNED)
 969                 tfputs(T("WIM_RESHDR_FLAG_SPANNED, "), out);
 970         if (flags & WIM_RESHDR_FLAG_CONCAT)
 971                 tfputs(T("WIM_RESHDR_FLAG_CONCAT, "), out);
 972         tputc(T('\n'), out);
 973         switch (lte->resource_location) {
 974         case RESOURCE_IN_WIM:
 975                 if (lte->rspec->wim->filename) {
 976                         tfprintf(out, T("WIM file              = `%"TS"'\n"),
 977                                  lte->rspec->wim->filename);
 978                 }
 979                 break;
 980 #ifdef __WIN32__
 981         case RESOURCE_WIN32_ENCRYPTED:
 982 #endif
 983         case RESOURCE_IN_FILE_ON_DISK:
 984                 tfprintf(out, T("File on Disk          = `%"TS"'\n"),
 985                          lte->file_on_disk);
 986                 break;
 987 #ifdef WITH_FUSE
 988         case RESOURCE_IN_STAGING_FILE:
 989                 tfprintf(out, T("Staging File          = `%"TS"'\n"),
 990                                 lte->staging_file_name);
 991                 break;
 992 #endif
 993         default:
 994                 break;
 995         }
 996         tputc(T('\n'), out);
 997 }
 998
 999 void
1000 lte_to_wimlib_resource_entry(const struct wim_lookup_table_entry *lte,
1001                              struct wimlib_resource_entry *wentry)
1002 {
1003         memset(wentry, 0, sizeof(*wentry));
1004
1005         wentry->uncompressed_size = lte->size;
1006         if (lte->resource_location == RESOURCE_IN_WIM) {
1007                 wentry->part_number = lte->rspec->wim->hdr.part_number;
1008                 if (lte_is_partial(lte)) {
1009                         wentry->compressed_size = 0;
1010                         wentry->offset = lte->offset_in_res;
1011                 } else {
1012                         wentry->compressed_size = lte->rspec->size_in_wim;
1013                         wentry->offset = lte->rspec->offset_in_wim;
1014                 }
1015                 wentry->raw_resource_offset_in_wim = lte->rspec->offset_in_wim;
1016                 wentry->raw_resource_uncompressed_size = lte->rspec->uncompressed_size;
1017                 wentry->raw_resource_compressed_size = lte->rspec->size_in_wim;
1018         }
1019         copy_hash(wentry->sha1_hash, lte->hash);
1020         wentry->reference_count = lte->refcnt;
1021         wentry->is_compressed = (lte->flags & WIM_RESHDR_FLAG_COMPRESSED) != 0;
1022         wentry->is_metadata = (lte->flags & WIM_RESHDR_FLAG_METADATA) != 0;
1023         wentry->is_free = (lte->flags & WIM_RESHDR_FLAG_FREE) != 0;
1024         wentry->is_spanned = (lte->flags & WIM_RESHDR_FLAG_SPANNED) != 0;
1025         wentry->is_partial = lte_is_partial(lte);
1026 }
1027
1028 struct iterate_lte_context {
1029         wimlib_iterate_lookup_table_callback_t cb;
1030         void *user_ctx;
1031 };
1032
1033 static int
1034 do_iterate_lte(struct wim_lookup_table_entry *lte, void *_ctx)
1035 {
1036         struct iterate_lte_context *ctx = _ctx;
1037         struct wimlib_resource_entry entry;
1038
1039         lte_to_wimlib_resource_entry(lte, &entry);
1040         return (*ctx->cb)(&entry, ctx->user_ctx);
1041 }
1042
1043 /* API function documented in wimlib.h  */
1044 WIMLIBAPI int
1045 wimlib_iterate_lookup_table(WIMStruct *wim, int flags,
1046                             wimlib_iterate_lookup_table_callback_t cb,
1047                             void *user_ctx)
1048 {
1049         struct iterate_lte_context ctx = {
1050                 .cb = cb,
1051                 .user_ctx = user_ctx,
1052         };
1053         if (wim->hdr.part_number == 1) {
1054                 int ret;
1055                 for (int i = 0; i < wim->hdr.image_count; i++) {
1056                         ret = do_iterate_lte(wim->image_metadata[i]->metadata_lte,
1057                                              &ctx);
1058                         if (ret)
1059                                 return ret;
1060                 }
1061         }
1062         return for_lookup_table_entry(wim->lookup_table, do_iterate_lte, &ctx);
1063 }
1064
1065 /* Given a SHA1 message digest, return the corresponding entry in the WIM's
1066  * lookup table, or NULL if there is none.  */
1067 struct wim_lookup_table_entry *
1068 lookup_resource(const struct wim_lookup_table *table, const u8 hash[])
1069 {
1070         size_t i;
1071         struct wim_lookup_table_entry *lte;
1072         struct hlist_node *pos;
1073
1074         wimlib_assert(table != NULL);
1075         wimlib_assert(hash != NULL);
1076
1077         i = *(size_t*)hash % table->capacity;
1078         hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
1079                 if (hashes_equal(hash, lte->hash))
1080                         return lte;
1081         return NULL;
1082 }
1083
1084 #ifdef WITH_FUSE
1085 /*
1086  * Finds the dentry, lookup table entry, and stream index for a WIM file stream,
1087  * given a path name.
1088  *
1089  * This is only for pre-resolved inodes.
1090  */
1091 int
1092 wim_pathname_to_stream(WIMStruct *wim,
1093                        const tchar *path,
1094                        int lookup_flags,
1095                        struct wim_dentry **dentry_ret,
1096                        struct wim_lookup_table_entry **lte_ret,
1097                        u16 *stream_idx_ret)
1098 {
1099         struct wim_dentry *dentry;
1100         struct wim_lookup_table_entry *lte;
1101         u16 stream_idx;
1102         const tchar *stream_name = NULL;
1103         struct wim_inode *inode;
1104         tchar *p = NULL;
1105
1106         if (lookup_flags & LOOKUP_FLAG_ADS_OK) {
1107                 stream_name = path_stream_name(path);
1108                 if (stream_name) {
1109                         p = (tchar*)stream_name - 1;
1110                         *p = T('\0');
1111                 }
1112         }
1113
1114         dentry = get_dentry(wim, path);
1115         if (p)
1116                 *p = T(':');
1117         if (!dentry)
1118                 return -errno;
1119
1120         inode = dentry->d_inode;
1121
1122         if (!inode->i_resolved)
1123                 if (inode_resolve_ltes(inode, wim->lookup_table, false))
1124                         return -EIO;
1125
1126         if (!(lookup_flags & LOOKUP_FLAG_DIRECTORY_OK)
1127               && inode_is_directory(inode))
1128                 return -EISDIR;
1129
1130         if (stream_name) {
1131                 struct wim_ads_entry *ads_entry;
1132                 u16 ads_idx;
1133                 ads_entry = inode_get_ads_entry(inode, stream_name,
1134                                                 &ads_idx);
1135                 if (ads_entry) {
1136                         stream_idx = ads_idx + 1;
1137                         lte = ads_entry->lte;
1138                         goto out;
1139                 } else {
1140                         return -ENOENT;
1141                 }
1142         } else {
1143                 lte = inode_unnamed_stream_resolved(inode, &stream_idx);
1144         }
1145 out:
1146         if (dentry_ret)
1147                 *dentry_ret = dentry;
1148         if (lte_ret)
1149                 *lte_ret = lte;
1150         if (stream_idx_ret)
1151                 *stream_idx_ret = stream_idx;
1152         return 0;
1153 }
1154 #endif
1155
1156 int
1157 resource_not_found_error(const struct wim_inode *inode, const u8 *hash)
1158 {
1159         if (wimlib_print_errors) {
1160                 ERROR("\"%"TS"\": resource not found", inode_first_full_path(inode));
1161                 tfprintf(stderr, T("        SHA-1 message digest of missing resource:\n        "));
1162                 print_hash(hash, stderr);
1163                 tputc(T('\n'), stderr);
1164         }
1165         return WIMLIB_ERR_RESOURCE_NOT_FOUND;
1166 }
1167
1168 /*
1169  * Resolve an inode's lookup table entries.
1170  *
1171  * This replaces the SHA1 hash fields (which are used to lookup an entry in the
1172  * lookup table) with pointers directly to the lookup table entries.
1173  *
1174  * If @force is %false:
1175  *      If any needed SHA1 message digests are not found in the lookup table,
1176  *      WIMLIB_ERR_RESOURCE_NOT_FOUND is returned and the inode is left
1177  *      unmodified.
1178  * If @force is %true:
1179  *      If any needed SHA1 message digests are not found in the lookup table,
1180  *      new entries are allocated and inserted into the lookup table.
1181  */
1182 int
1183 inode_resolve_ltes(struct wim_inode *inode, struct wim_lookup_table *table,
1184                    bool force)
1185 {
1186         const u8 *hash;
1187
1188         if (!inode->i_resolved) {
1189                 struct wim_lookup_table_entry *lte, *ads_lte;
1190
1191                 /* Resolve the default file stream */
1192                 lte = NULL;
1193                 hash = inode->i_hash;
1194                 if (!is_zero_hash(hash)) {
1195                         lte = lookup_resource(table, hash);
1196                         if (!lte) {
1197                                 if (force) {
1198                                         lte = new_lookup_table_entry();
1199                                         if (!lte)
1200                                                 return WIMLIB_ERR_NOMEM;
1201                                         copy_hash(lte->hash, hash);
1202                                         lookup_table_insert(table, lte);
1203                                 } else {
1204                                         goto resource_not_found;
1205                                 }
1206                         }
1207                 }
1208
1209                 /* Resolve the alternate data streams */
1210                 struct wim_lookup_table_entry *ads_ltes[inode->i_num_ads];
1211                 for (u16 i = 0; i < inode->i_num_ads; i++) {
1212                         struct wim_ads_entry *cur_entry;
1213
1214                         ads_lte = NULL;
1215                         cur_entry = &inode->i_ads_entries[i];
1216                         hash = cur_entry->hash;
1217                         if (!is_zero_hash(hash)) {
1218                                 ads_lte = lookup_resource(table, hash);
1219                                 if (!ads_lte) {
1220                                         if (force) {
1221                                                 ads_lte = new_lookup_table_entry();
1222                                                 if (!ads_lte)
1223                                                         return WIMLIB_ERR_NOMEM;
1224                                                 copy_hash(ads_lte->hash, hash);
1225                                                 lookup_table_insert(table, ads_lte);
1226                                         } else {
1227                                                 goto resource_not_found;
1228                                         }
1229                                 }
1230                         }
1231                         ads_ltes[i] = ads_lte;
1232                 }
1233                 inode->i_lte = lte;
1234                 for (u16 i = 0; i < inode->i_num_ads; i++)
1235                         inode->i_ads_entries[i].lte = ads_ltes[i];
1236                 inode->i_resolved = 1;
1237         }
1238         return 0;
1239
1240 resource_not_found:
1241         return resource_not_found_error(inode, hash);
1242 }
1243
1244 void
1245 inode_unresolve_ltes(struct wim_inode *inode)
1246 {
1247         if (inode->i_resolved) {
1248                 if (inode->i_lte)
1249                         copy_hash(inode->i_hash, inode->i_lte->hash);
1250                 else
1251                         zero_out_hash(inode->i_hash);
1252
1253                 for (u16 i = 0; i < inode->i_num_ads; i++) {
1254                         if (inode->i_ads_entries[i].lte)
1255                                 copy_hash(inode->i_ads_entries[i].hash,
1256                                           inode->i_ads_entries[i].lte->hash);
1257                         else
1258                                 zero_out_hash(inode->i_ads_entries[i].hash);
1259                 }
1260                 inode->i_resolved = 0;
1261         }
1262 }
1263
1264 /*
1265  * Returns the lookup table entry for stream @stream_idx of the inode, where
1266  * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
1267  * corresponds to an alternate data stream.
1268  *
1269  * This works for both resolved and un-resolved inodes.
1270  */
1271 struct wim_lookup_table_entry *
1272 inode_stream_lte(const struct wim_inode *inode, unsigned stream_idx,
1273                  const struct wim_lookup_table *table)
1274 {
1275         if (inode->i_resolved)
1276                 return inode_stream_lte_resolved(inode, stream_idx);
1277         else
1278                 return inode_stream_lte_unresolved(inode, stream_idx, table);
1279 }
1280
1281 struct wim_lookup_table_entry *
1282 inode_unnamed_stream_resolved(const struct wim_inode *inode, u16 *stream_idx_ret)
1283 {
1284         wimlib_assert(inode->i_resolved);
1285         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1286                 if (inode_stream_name_nbytes(inode, i) == 0 &&
1287                     !is_zero_hash(inode_stream_hash_resolved(inode, i)))
1288                 {
1289                         *stream_idx_ret = i;
1290                         return inode_stream_lte_resolved(inode, i);
1291                 }
1292         }
1293         *stream_idx_ret = 0;
1294         return NULL;
1295 }
1296
1297 struct wim_lookup_table_entry *
1298 inode_unnamed_lte_resolved(const struct wim_inode *inode)
1299 {
1300         u16 stream_idx;
1301         return inode_unnamed_stream_resolved(inode, &stream_idx);
1302 }
1303
1304 struct wim_lookup_table_entry *
1305 inode_unnamed_lte_unresolved(const struct wim_inode *inode,
1306                              const struct wim_lookup_table *table)
1307 {
1308         wimlib_assert(!inode->i_resolved);
1309         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1310                 if (inode_stream_name_nbytes(inode, i) == 0 &&
1311                     !is_zero_hash(inode_stream_hash_unresolved(inode, i)))
1312                 {
1313                         return inode_stream_lte_unresolved(inode, i, table);
1314                 }
1315         }
1316         return NULL;
1317 }
1318
1319 /* Return the lookup table entry for the unnamed data stream of an inode, or
1320  * NULL if there is none.
1321  *
1322  * You'd think this would be easier than it actually is, since the unnamed data
1323  * stream should be the one referenced from the inode itself.  Alas, if there
1324  * are named data streams, Microsoft's "imagex.exe" program will put the unnamed
1325  * data stream in one of the alternate data streams instead of inside the WIM
1326  * dentry itself.  So we need to check the alternate data streams too.
1327  *
1328  * Also, note that a dentry may appear to have more than one unnamed stream, but
1329  * if the SHA1 message digest is all 0's then the corresponding stream does not
1330  * really "count" (this is the case for the inode's own file stream when the
1331  * file stream that should be there is actually in one of the alternate stream
1332  * entries.).  This is despite the fact that we may need to extract such a
1333  * missing entry as an empty file or empty named data stream.
1334  */
1335 struct wim_lookup_table_entry *
1336 inode_unnamed_lte(const struct wim_inode *inode,
1337                   const struct wim_lookup_table *table)
1338 {
1339         if (inode->i_resolved)
1340                 return inode_unnamed_lte_resolved(inode);
1341         else
1342                 return inode_unnamed_lte_unresolved(inode, table);
1343 }
1344
1345 /* Returns the SHA1 message digest of the unnamed data stream of a WIM inode, or
1346  * 'zero_hash' if the unnamed data stream is missing has all zeroes in its SHA1
1347  * message digest field.  */
1348 const u8 *
1349 inode_unnamed_stream_hash(const struct wim_inode *inode)
1350 {
1351         const u8 *hash;
1352
1353         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1354                 if (inode_stream_name_nbytes(inode, i) == 0) {
1355                         hash = inode_stream_hash(inode, i);
1356                         if (!is_zero_hash(hash))
1357                                 return hash;
1358                 }
1359         }
1360         return zero_hash;
1361 }
1362
1363 struct wim_lookup_table_entry **
1364 retrieve_lte_pointer(struct wim_lookup_table_entry *lte)
1365 {
1366         wimlib_assert(lte->unhashed);
1367         struct wim_inode *inode = lte->back_inode;
1368         u32 stream_id = lte->back_stream_id;
1369         if (stream_id == 0)
1370                 return &inode->i_lte;
1371         else
1372                 for (u16 i = 0; i < inode->i_num_ads; i++)
1373                         if (inode->i_ads_entries[i].stream_id == stream_id)
1374                                 return &inode->i_ads_entries[i].lte;
1375         wimlib_assert(0);
1376         return NULL;
1377 }
1378
1379 /* Calculate the SHA1 message digest of a stream and move it from the list of
1380  * unhashed streams to the stream lookup table, possibly joining it with an
1381  * existing lookup table entry for an identical stream.
1382  *
1383  * @lte:  An unhashed lookup table entry.
1384  * @lookup_table:  Lookup table for the WIM.
1385  * @lte_ret:  On success, write a pointer to the resulting lookup table
1386  *            entry to this location.  This will be the same as @lte
1387  *            if it was inserted into the lookup table, or different if
1388  *            a duplicate stream was found.
1389  *
1390  * Returns 0 on success; nonzero if there is an error reading the stream.
1391  */
1392 int
1393 hash_unhashed_stream(struct wim_lookup_table_entry *lte,
1394                      struct wim_lookup_table *lookup_table,
1395                      struct wim_lookup_table_entry **lte_ret)
1396 {
1397         int ret;
1398         struct wim_lookup_table_entry *duplicate_lte;
1399         struct wim_lookup_table_entry **back_ptr;
1400
1401         wimlib_assert(lte->unhashed);
1402
1403         /* back_ptr must be saved because @back_inode and @back_stream_id are in
1404          * union with the SHA1 message digest and will no longer be valid once
1405          * the SHA1 has been calculated. */
1406         back_ptr = retrieve_lte_pointer(lte);
1407
1408         ret = sha1_stream(lte);
1409         if (ret)
1410                 return ret;
1411
1412         /* Look for a duplicate stream */
1413         duplicate_lte = lookup_resource(lookup_table, lte->hash);
1414         list_del(&lte->unhashed_list);
1415         if (duplicate_lte) {
1416                 /* We have a duplicate stream.  Transfer the reference counts
1417                  * from this stream to the duplicate, update the reference to
1418                  * this stream (in an inode or ads_entry) to point to the
1419                  * duplicate, then free this stream. */
1420                 wimlib_assert(!(duplicate_lte->unhashed));
1421                 duplicate_lte->refcnt += lte->refcnt;
1422                 duplicate_lte->out_refcnt += lte->out_refcnt;
1423                 *back_ptr = duplicate_lte;
1424                 free_lookup_table_entry(lte);
1425                 lte = duplicate_lte;
1426         } else {
1427                 /* No duplicate stream, so we need to insert
1428                  * this stream into the lookup table and treat
1429                  * it as a hashed stream. */
1430                 lookup_table_insert(lookup_table, lte);
1431                 lte->unhashed = 0;
1432         }
1433         if (lte_ret)
1434                 *lte_ret = lte;
1435         return 0;
1436 }
1437
1438 static int
1439 lte_clone_if_new(struct wim_lookup_table_entry *lte, void *_lookup_table)
1440 {
1441         struct wim_lookup_table *lookup_table = _lookup_table;
1442
1443         if (lookup_resource(lookup_table, lte->hash))
1444                 return 0;  /*  Resource already present.  */
1445
1446         lte = clone_lookup_table_entry(lte);
1447         if (!lte)
1448                 return WIMLIB_ERR_NOMEM;
1449         lte->out_refcnt = 1;
1450         lookup_table_insert(lookup_table, lte);
1451         return 0;
1452 }
1453
1454 static int
1455 lte_delete_if_new(struct wim_lookup_table_entry *lte, void *_lookup_table)
1456 {
1457         struct wim_lookup_table *lookup_table = _lookup_table;
1458
1459         if (lte->out_refcnt) {
1460                 lookup_table_unlink(lookup_table, lte);
1461                 free_lookup_table_entry(lte);
1462         }
1463         return 0;
1464 }
1465
1466 /* API function documented in wimlib.h  */
1467 WIMLIBAPI int
1468 wimlib_reference_resources(WIMStruct *wim,
1469                            WIMStruct **resource_wims, unsigned num_resource_wims,
1470                            int ref_flags)
1471 {
1472         int ret;
1473         unsigned i;
1474
1475         if (wim == NULL)
1476                 return WIMLIB_ERR_INVALID_PARAM;
1477
1478         if (num_resource_wims != 0 && resource_wims == NULL)
1479                 return WIMLIB_ERR_INVALID_PARAM;
1480
1481         for (i = 0; i < num_resource_wims; i++)
1482                 if (resource_wims[i] == NULL)
1483                         return WIMLIB_ERR_INVALID_PARAM;
1484
1485         for_lookup_table_entry(wim->lookup_table, lte_zero_out_refcnt, NULL);
1486
1487         for (i = 0; i < num_resource_wims; i++) {
1488                 ret = for_lookup_table_entry(resource_wims[i]->lookup_table,
1489                                              lte_clone_if_new,
1490                                              wim->lookup_table);
1491                 if (ret)
1492                         goto out_rollback;
1493         }
1494         return 0;
1495
1496 out_rollback:
1497         for_lookup_table_entry(wim->lookup_table, lte_delete_if_new,
1498                                wim->lookup_table);
1499         return ret;
1500 }
1501
1502 static int
1503 reference_resource_paths(WIMStruct *wim,
1504                          const tchar * const *resource_wimfiles,
1505                          unsigned num_resource_wimfiles,
1506                          int ref_flags,
1507                          int open_flags,
1508                          wimlib_progress_func_t progress_func)
1509 {
1510         WIMStruct **resource_wims;
1511         unsigned i;
1512         int ret;
1513
1514         resource_wims = CALLOC(num_resource_wimfiles, sizeof(resource_wims[0]));
1515         if (!resource_wims)
1516                 return WIMLIB_ERR_NOMEM;
1517
1518         for (i = 0; i < num_resource_wimfiles; i++) {
1519                 DEBUG("Referencing resources from path \"%"TS"\"",
1520                       resource_wimfiles[i]);
1521                 ret = wimlib_open_wim(resource_wimfiles[i], open_flags,
1522                                       &resource_wims[i], progress_func);
1523                 if (ret)
1524                         goto out_free_resource_wims;
1525         }
1526
1527         ret = wimlib_reference_resources(wim, resource_wims,
1528                                          num_resource_wimfiles, ref_flags);
1529         if (ret)
1530                 goto out_free_resource_wims;
1531
1532         for (i = 0; i < num_resource_wimfiles; i++)
1533                 list_add_tail(&resource_wims[i]->subwim_node, &wim->subwims);
1534
1535         ret = 0;
1536         goto out_free_array;
1537
1538 out_free_resource_wims:
1539         for (i = 0; i < num_resource_wimfiles; i++)
1540                 wimlib_free(resource_wims[i]);
1541 out_free_array:
1542         FREE(resource_wims);
1543         return ret;
1544 }
1545
1546 static int
1547 reference_resource_glob(WIMStruct *wim, const tchar *refglob,
1548                         int ref_flags, int open_flags,
1549                         wimlib_progress_func_t progress_func)
1550 {
1551         glob_t globbuf;
1552         int ret;
1553
1554         /* Note: glob() is replaced in Windows native builds.  */
1555         ret = tglob(refglob, GLOB_ERR | GLOB_NOSORT, NULL, &globbuf);
1556         if (ret) {
1557                 if (ret == GLOB_NOMATCH) {
1558                         if (ref_flags & WIMLIB_REF_FLAG_GLOB_ERR_ON_NOMATCH) {
1559                                 ERROR("Found no files for glob \"%"TS"\"", refglob);
1560                                 return WIMLIB_ERR_GLOB_HAD_NO_MATCHES;
1561                         } else {
1562                                 return reference_resource_paths(wim,
1563                                                                 &refglob,
1564                                                                 1,
1565                                                                 ref_flags,
1566                                                                 open_flags,
1567                                                                 progress_func);
1568                         }
1569                 } else {
1570                         ERROR_WITH_ERRNO("Failed to process glob \"%"TS"\"", refglob);
1571                         if (ret == GLOB_NOSPACE)
1572                                 return WIMLIB_ERR_NOMEM;
1573                         else
1574                                 return WIMLIB_ERR_READ;
1575                 }
1576         }
1577
1578         ret = reference_resource_paths(wim,
1579                                        (const tchar * const *)globbuf.gl_pathv,
1580                                        globbuf.gl_pathc,
1581                                        ref_flags,
1582                                        open_flags,
1583                                        progress_func);
1584         globfree(&globbuf);
1585         return ret;
1586 }
1587
1588 /* API function documented in wimlib.h  */
1589 WIMLIBAPI int
1590 wimlib_reference_resource_files(WIMStruct *wim,
1591                                 const tchar * const * resource_wimfiles_or_globs,
1592                                 unsigned count,
1593                                 int ref_flags,
1594                                 int open_flags,
1595                                 wimlib_progress_func_t progress_func)
1596 {
1597         unsigned i;
1598         int ret;
1599
1600         if (ref_flags & WIMLIB_REF_FLAG_GLOB_ENABLE) {
1601                 for (i = 0; i < count; i++) {
1602                         ret = reference_resource_glob(wim,
1603                                                       resource_wimfiles_or_globs[i],
1604                                                       ref_flags,
1605                                                       open_flags,
1606                                                       progress_func);
1607                         if (ret)
1608                                 return ret;
1609                 }
1610                 return 0;
1611         } else {
1612                 return reference_resource_paths(wim, resource_wimfiles_or_globs,
1613                                                 count, ref_flags,
1614                                                 open_flags, progress_func);
1615         }
1616 }