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   1 /*
   2  * lookup_table.c
   3  *
   4  * Lookup table, implemented as a hash table, that maps dentries to file
   5  * resources.
   6  */
   7
   8 /*
   9  * Copyright (C) 2012 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 #include "wimlib_internal.h"
  28 #include "lookup_table.h"
  29 #include "buffer_io.h"
  30 #include <errno.h>
  31
  32 #ifdef WITH_FUSE
  33 #include <unistd.h>
  34 #endif
  35
  36 struct lookup_table *new_lookup_table(size_t capacity)
  37 {
  38         struct lookup_table *table;
  39         struct hlist_head *array;
  40
  41         table = MALLOC(sizeof(struct lookup_table));
  42         if (table) {
  43                 array = CALLOC(capacity, sizeof(array[0]));
  44                 if (array) {
  45                         table->num_entries = 0;
  46                         table->capacity = capacity;
  47                         table->array = array;
  48                 } else {
  49                         FREE(table);
  50                         table = NULL;
  51                         ERROR("Failed to allocate memory for lookup table with capacity %zu",
  52                               capacity);
  53                 }
  54         }
  55         return table;
  56 }
  57
  58 struct lookup_table_entry *new_lookup_table_entry()
  59 {
  60         struct lookup_table_entry *lte;
  61
  62         lte = CALLOC(1, sizeof(struct lookup_table_entry));
  63         if (lte) {
  64                 lte->part_number  = 1;
  65                 lte->refcnt       = 1;
  66         } else {
  67                 ERROR("Out of memory (tried to allocate %zu bytes for "
  68                       "lookup table entry)",
  69                       sizeof(struct lookup_table_entry));
  70         }
  71         return lte;
  72 }
  73
  74 struct lookup_table_entry *
  75 clone_lookup_table_entry(const struct lookup_table_entry *old)
  76 {
  77         struct lookup_table_entry *new;
  78
  79         new = MALLOC(sizeof(*new));
  80         if (!new)
  81                 return NULL;
  82
  83         memcpy(new, old, sizeof(*old));
  84         new->extracted_file = NULL;
  85         switch (new->resource_location) {
  86         case RESOURCE_IN_STAGING_FILE:
  87         case RESOURCE_IN_FILE_ON_DISK:
  88                 wimlib_assert((void*)&old->file_on_disk ==
  89                               (void*)&old->staging_file_name);
  90                 new->staging_file_name = STRDUP(old->staging_file_name);
  91                 if (!new->staging_file_name)
  92                         goto out_free;
  93                 break;
  94         case RESOURCE_IN_ATTACHED_BUFFER:
  95                 new->attached_buffer = MALLOC(wim_resource_size(old));
  96                 if (!new->attached_buffer)
  97                         goto out_free;
  98                 memcpy(new->attached_buffer, old->attached_buffer,
  99                        wim_resource_size(old));
 100                 break;
 101 #ifdef WITH_NTFS_3G
 102         case RESOURCE_IN_NTFS_VOLUME:
 103                 if (old->ntfs_loc) {
 104                         struct ntfs_location *loc;
 105                         loc = MALLOC(sizeof(*loc));
 106                         if (!loc)
 107                                 goto out_free;
 108                         memcpy(loc, old->ntfs_loc, sizeof(*loc));
 109                         loc->path_utf8 = NULL;
 110                         loc->stream_name_utf16 = NULL;
 111                         new->ntfs_loc = loc;
 112                         loc->path_utf8 = STRDUP(old->ntfs_loc->path_utf8);
 113                         if (!loc->path_utf8)
 114                                 goto out_free;
 115                         loc->stream_name_utf16 = MALLOC(loc->stream_name_utf16_num_chars * 2);
 116                         if (!loc->stream_name_utf16)
 117                                 goto out_free;
 118                         memcpy(loc->stream_name_utf16,
 119                                old->ntfs_loc->stream_name_utf16,
 120                                loc->stream_name_utf16_num_chars * 2);
 121                 }
 122                 break;
 123 #endif
 124         default:
 125                 break;
 126         }
 127         return new;
 128 out_free:
 129         free_lookup_table_entry(new);
 130         return NULL;
 131 }
 132
 133 void free_lookup_table_entry(struct lookup_table_entry *lte)
 134 {
 135         if (lte) {
 136                 switch (lte->resource_location) {
 137                 case RESOURCE_IN_STAGING_FILE:
 138                 case RESOURCE_IN_ATTACHED_BUFFER:
 139                 case RESOURCE_IN_FILE_ON_DISK:
 140                         wimlib_assert(((void*)&lte->file_on_disk ==
 141                                       (void*)&lte->staging_file_name)
 142                                       && ((void*)&lte->file_on_disk ==
 143                                       (void*)&lte->attached_buffer));
 144                         FREE(lte->file_on_disk);
 145                         break;
 146 #ifdef WITH_NTFS_3G
 147                 case RESOURCE_IN_NTFS_VOLUME:
 148                         if (lte->ntfs_loc) {
 149                                 FREE(lte->ntfs_loc->path_utf8);
 150                                 FREE(lte->ntfs_loc->stream_name_utf16);
 151                                 FREE(lte->ntfs_loc);
 152                         }
 153                         break;
 154 #endif
 155                 default:
 156                         break;
 157                 }
 158                 FREE(lte);
 159         }
 160 }
 161
 162 static int do_free_lookup_table_entry(struct lookup_table_entry *entry,
 163                                       void *ignore)
 164 {
 165         free_lookup_table_entry(entry);
 166         return 0;
 167 }
 168
 169
 170 void free_lookup_table(struct lookup_table *table)
 171 {
 172         DEBUG2("Freeing lookup table");
 173         if (table) {
 174                 if (table->array) {
 175                         for_lookup_table_entry(table,
 176                                                do_free_lookup_table_entry,
 177                                                NULL);
 178                         FREE(table->array);
 179                 }
 180                 FREE(table);
 181         }
 182 }
 183
 184 /*
 185  * Inserts an entry into the lookup table.
 186  *
 187  * @table:      A pointer to the lookup table.
 188  * @entry:      A pointer to the entry to insert.
 189  */
 190 void lookup_table_insert(struct lookup_table *table,
 191                          struct lookup_table_entry *lte)
 192 {
 193         size_t i = lte->hash_short % table->capacity;
 194         hlist_add_head(&lte->hash_list, &table->array[i]);
 195
 196         /* XXX Make the table grow when too many entries have been inserted. */
 197         table->num_entries++;
 198 }
 199
 200 static void finalize_lte(struct lookup_table_entry *lte)
 201 {
 202         #ifdef WITH_FUSE
 203         if (lte->resource_location == RESOURCE_IN_STAGING_FILE) {
 204                 unlink(lte->staging_file_name);
 205                 list_del(&lte->staging_list);
 206         }
 207         #endif
 208         free_lookup_table_entry(lte);
 209 }
 210
 211 /* Decrements the reference count for the lookup table entry @lte.  If its
 212  * reference count reaches 0, it is unlinked from the lookup table.  If,
 213  * furthermore, the entry has no opened file descriptors associated with it, the
 214  * entry is freed.  */
 215 void lte_decrement_refcnt(struct lookup_table_entry *lte,
 216                           struct lookup_table *table)
 217 {
 218         wimlib_assert(lte != NULL);
 219         wimlib_assert(lte->refcnt != 0);
 220         if (--lte->refcnt == 0) {
 221                 lookup_table_unlink(table, lte);
 222         #ifdef WITH_FUSE
 223                 if (lte->num_opened_fds == 0)
 224         #endif
 225                         finalize_lte(lte);
 226         }
 227 }
 228
 229 #ifdef WITH_FUSE
 230 void lte_decrement_num_opened_fds(struct lookup_table_entry *lte)
 231 {
 232         if (lte->num_opened_fds != 0)
 233                 if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
 234                         finalize_lte(lte);
 235 }
 236 #endif
 237
 238 /*
 239  * Calls a function on all the entries in the lookup table.  Stop early and
 240  * return nonzero if any call to the function returns nonzero.
 241  */
 242 int for_lookup_table_entry(struct lookup_table *table,
 243                            int (*visitor)(struct lookup_table_entry *, void *),
 244                            void *arg)
 245 {
 246         struct lookup_table_entry *lte;
 247         struct hlist_node *pos, *tmp;
 248         int ret;
 249
 250         for (size_t i = 0; i < table->capacity; i++) {
 251                 hlist_for_each_entry_safe(lte, pos, tmp, &table->array[i],
 252                                           hash_list)
 253                 {
 254                         ret = visitor(lte, arg);
 255                         if (ret != 0)
 256                                 return ret;
 257                 }
 258         }
 259         return 0;
 260 }
 261
 262
 263 /*
 264  * Reads the lookup table from a WIM file.
 265  */
 266 int read_lookup_table(WIMStruct *w)
 267 {
 268         u64 num_entries;
 269         u8 buf[WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE];
 270         int ret;
 271         struct lookup_table *table;
 272         struct lookup_table_entry *cur_entry = NULL, *duplicate_entry;
 273
 274         if (resource_is_compressed(&w->hdr.lookup_table_res_entry)) {
 275                 ERROR("Didn't expect a compressed lookup table!");
 276                 ERROR("Ask the author to implement support for this.");
 277                 return WIMLIB_ERR_COMPRESSED_LOOKUP_TABLE;
 278         }
 279
 280         DEBUG("Reading lookup table: offset %"PRIu64", size %"PRIu64"",
 281               w->hdr.lookup_table_res_entry.offset,
 282               w->hdr.lookup_table_res_entry.original_size);
 283
 284         if (fseeko(w->fp, w->hdr.lookup_table_res_entry.offset, SEEK_SET) != 0)
 285         {
 286                 ERROR_WITH_ERRNO("Failed to seek to byte %"PRIu64" to read "
 287                                  "lookup table",
 288                                  w->hdr.lookup_table_res_entry.offset);
 289                 return WIMLIB_ERR_READ;
 290         }
 291
 292         num_entries = w->hdr.lookup_table_res_entry.original_size /
 293                       WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE;
 294         table = new_lookup_table(num_entries * 2 + 1);
 295         if (!table)
 296                 return WIMLIB_ERR_NOMEM;
 297
 298         while (num_entries--) {
 299                 const u8 *p;
 300
 301                 if (fread(buf, 1, sizeof(buf), w->fp) != sizeof(buf)) {
 302                         if (feof(w->fp)) {
 303                                 ERROR("Unexpected EOF in WIM lookup table!");
 304                         } else {
 305                                 ERROR_WITH_ERRNO("Error reading WIM lookup "
 306                                                  "table");
 307                         }
 308                         ret = WIMLIB_ERR_READ;
 309                         goto out;
 310                 }
 311                 cur_entry = new_lookup_table_entry();
 312                 if (!cur_entry) {
 313                         ret = WIMLIB_ERR_NOMEM;
 314                         goto out;
 315                 }
 316                 cur_entry->wim = w;
 317                 cur_entry->resource_location = RESOURCE_IN_WIM;
 318
 319                 p = get_resource_entry(buf, &cur_entry->resource_entry);
 320                 p = get_u16(p, &cur_entry->part_number);
 321                 p = get_u32(p, &cur_entry->refcnt);
 322                 p = get_bytes(p, SHA1_HASH_SIZE, cur_entry->hash);
 323
 324                 if (cur_entry->part_number != w->hdr.part_number) {
 325                         ERROR("A lookup table entry in part %hu of the WIM "
 326                               "points to part %hu",
 327                               w->hdr.part_number, cur_entry->part_number);
 328                         ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 329                         goto out_free_cur_entry;
 330                 }
 331
 332                 if (is_zero_hash(cur_entry->hash)) {
 333                         ERROR("The WIM lookup table contains an entry with a "
 334                               "SHA1 message digest of all 0's");
 335                         ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 336                         goto out_free_cur_entry;
 337                 }
 338
 339                 /* Ordinarily, no two streams should share the same SHA1 message
 340                  * digest.  However, this constraint can be broken for metadata
 341                  * resources--- two identical images will have the same metadata
 342                  * resource, but their lookup table entries are not shared. */
 343                 duplicate_entry = __lookup_resource(table, cur_entry->hash);
 344                 if (duplicate_entry
 345                     && !((duplicate_entry->resource_entry.flags & WIM_RESHDR_FLAG_METADATA)
 346                           && cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_METADATA))
 347                 {
 348                         ERROR("The WIM lookup table contains two entries with the "
 349                               "same SHA1 message digest!");
 350                         ERROR("The first entry is:");
 351                         print_lookup_table_entry(duplicate_entry);
 352                         ERROR("The second entry is:");
 353                         print_lookup_table_entry(cur_entry);
 354                         ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 355                         goto out_free_cur_entry;
 356                 }
 357
 358                 if (!(cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
 359                     && (cur_entry->resource_entry.size !=
 360                         cur_entry->resource_entry.original_size))
 361                 {
 362                         ERROR("Found uncompressed resource with original size "
 363                               "not the same as compressed size");
 364                         ERROR("The lookup table entry for the resource is as follows:");
 365                         print_lookup_table_entry(cur_entry);
 366                         ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 367                         goto out_free_cur_entry;
 368                 }
 369                 if ((cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_METADATA)
 370                     && cur_entry->refcnt != 1)
 371                 {
 372                         ERROR("Found metadata resource with refcnt != 1:");
 373                         print_lookup_table_entry(cur_entry);
 374                         ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 375                         goto out_free_cur_entry;
 376                 }
 377                 lookup_table_insert(table, cur_entry);
 378
 379         }
 380         DEBUG("Done reading lookup table.");
 381         w->lookup_table = table;
 382         return 0;
 383 out_free_cur_entry:
 384         FREE(cur_entry);
 385 out:
 386         free_lookup_table(table);
 387         return ret;
 388 }
 389
 390
 391 /*
 392  * Writes a lookup table entry to the output file.
 393  */
 394 int write_lookup_table_entry(struct lookup_table_entry *lte, void *__out)
 395 {
 396         FILE *out;
 397         u8 buf[WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE];
 398         u8 *p;
 399
 400         out = __out;
 401
 402         /* Don't write entries that have not had file resources or metadata
 403          * resources written for them. */
 404         if (lte->out_refcnt == 0)
 405                 return 0;
 406
 407         if (lte->output_resource_entry.flags & WIM_RESHDR_FLAG_METADATA)
 408                 DEBUG("Writing metadata entry at %lu (orig size = %zu)",
 409                       ftello(out), lte->output_resource_entry.original_size);
 410
 411         p = put_resource_entry(buf, &lte->output_resource_entry);
 412         p = put_u16(p, lte->part_number);
 413         p = put_u32(p, lte->out_refcnt);
 414         p = put_bytes(p, SHA1_HASH_SIZE, lte->hash);
 415         if (fwrite(buf, 1, sizeof(buf), out) != sizeof(buf)) {
 416                 ERROR_WITH_ERRNO("Failed to write lookup table entry");
 417                 return WIMLIB_ERR_WRITE;
 418         }
 419         return 0;
 420 }
 421
 422 /* Writes the lookup table to the output file. */
 423 int write_lookup_table(struct lookup_table *table, FILE *out,
 424                        struct resource_entry *out_res_entry)
 425 {
 426         off_t start_offset, end_offset;
 427         int ret;
 428
 429         start_offset = ftello(out);
 430         if (start_offset == -1)
 431                 return WIMLIB_ERR_WRITE;
 432
 433         ret = for_lookup_table_entry(table, write_lookup_table_entry, out);
 434         if (ret != 0)
 435                 return ret;
 436
 437         end_offset = ftello(out);
 438         if (end_offset == -1)
 439                 return WIMLIB_ERR_WRITE;
 440
 441         out_res_entry->offset        = start_offset;
 442         out_res_entry->size          = end_offset - start_offset;
 443         out_res_entry->original_size = end_offset - start_offset;
 444         out_res_entry->flags         = WIM_RESHDR_FLAG_METADATA;
 445
 446         return 0;
 447 }
 448
 449
 450 int lte_zero_real_refcnt(struct lookup_table_entry *lte, void *ignore)
 451 {
 452         lte->real_refcnt = 0;
 453         return 0;
 454 }
 455
 456 int lte_zero_out_refcnt(struct lookup_table_entry *lte, void *ignore)
 457 {
 458         lte->out_refcnt = 0;
 459         return 0;
 460 }
 461
 462 int lte_free_extracted_file(struct lookup_table_entry *lte, void *ignore)
 463 {
 464         if (lte->extracted_file != NULL) {
 465                 FREE(lte->extracted_file);
 466                 lte->extracted_file = NULL;
 467         }
 468         return 0;
 469 }
 470
 471 void print_lookup_table_entry(const struct lookup_table_entry *lte)
 472 {
 473         if (!lte) {
 474                 putchar('\n');
 475                 return;
 476         }
 477         printf("Offset            = %"PRIu64" bytes\n",
 478                lte->resource_entry.offset);
 479         printf("Size              = %"PRIu64" bytes\n",
 480                (u64)lte->resource_entry.size);
 481         printf("Original size     = %"PRIu64" bytes\n",
 482                lte->resource_entry.original_size);
 483         printf("Part Number       = %hu\n", lte->part_number);
 484         printf("Reference Count   = %u\n", lte->refcnt);
 485         printf("Hash              = 0x");
 486         print_hash(lte->hash);
 487         putchar('\n');
 488         printf("Flags             = ");
 489         u8 flags = lte->resource_entry.flags;
 490         if (flags & WIM_RESHDR_FLAG_COMPRESSED)
 491                 fputs("WIM_RESHDR_FLAG_COMPRESSED, ", stdout);
 492         if (flags & WIM_RESHDR_FLAG_FREE)
 493                 fputs("WIM_RESHDR_FLAG_FREE, ", stdout);
 494         if (flags & WIM_RESHDR_FLAG_METADATA)
 495                 fputs("WIM_RESHDR_FLAG_METADATA, ", stdout);
 496         if (flags & WIM_RESHDR_FLAG_SPANNED)
 497                 fputs("WIM_RESHDR_FLAG_SPANNED, ", stdout);
 498         putchar('\n');
 499         switch (lte->resource_location) {
 500         case RESOURCE_IN_WIM:
 501                 if (lte->wim->filename) {
 502                         printf("WIM file          = `%s'\n",
 503                                lte->wim->filename);
 504                 }
 505                 break;
 506         case RESOURCE_IN_FILE_ON_DISK:
 507                 printf("File on Disk      = `%s'\n", lte->file_on_disk);
 508                 break;
 509         case RESOURCE_IN_STAGING_FILE:
 510                 printf("Staging File      = `%s'\n", lte->staging_file_name);
 511                 break;
 512         default:
 513                 break;
 514         }
 515         putchar('\n');
 516 }
 517
 518 static int do_print_lookup_table_entry(struct lookup_table_entry *lte,
 519                                        void *ignore)
 520 {
 521         print_lookup_table_entry(lte);
 522         return 0;
 523 }
 524
 525 /*
 526  * Prints the lookup table of a WIM file.
 527  */
 528 WIMLIBAPI void wimlib_print_lookup_table(WIMStruct *w)
 529 {
 530         for_lookup_table_entry(w->lookup_table,
 531                                do_print_lookup_table_entry,
 532                                NULL);
 533 }
 534
 535 /*
 536  * Looks up an entry in the lookup table.
 537  */
 538 struct lookup_table_entry *
 539 __lookup_resource(const struct lookup_table *table, const u8 hash[])
 540 {
 541         size_t i;
 542         struct lookup_table_entry *lte;
 543         struct hlist_node *pos;
 544
 545         wimlib_assert(table != NULL);
 546         wimlib_assert(hash != NULL);
 547
 548         i = *(size_t*)hash % table->capacity;
 549         hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
 550                 if (hashes_equal(hash, lte->hash))
 551                         return lte;
 552         return NULL;
 553 }
 554
 555 #ifdef WITH_FUSE
 556 /*
 557  * Finds the dentry, lookup table entry, and stream index for a WIM file stream,
 558  * given a path name.
 559  *
 560  * This is only for pre-resolved inodes.
 561  */
 562 int lookup_resource(WIMStruct *w, const char *path,
 563                     int lookup_flags,
 564                     struct dentry **dentry_ret,
 565                     struct lookup_table_entry **lte_ret,
 566                     u16 *stream_idx_ret)
 567 {
 568         struct dentry *dentry;
 569         struct lookup_table_entry *lte;
 570         u16 stream_idx;
 571         const char *stream_name = NULL;
 572         struct inode *inode;
 573         char *p = NULL;
 574
 575         if (lookup_flags & LOOKUP_FLAG_ADS_OK) {
 576                 stream_name = path_stream_name(path);
 577                 if (stream_name) {
 578                         p = (char*)stream_name - 1;
 579                         *p = '\0';
 580                 }
 581         }
 582
 583         dentry = get_dentry(w, path);
 584         if (p)
 585                 *p = ':';
 586         if (!dentry)
 587                 return -ENOENT;
 588
 589         inode = dentry->d_inode;
 590
 591         wimlib_assert(inode->resolved);
 592
 593         if (!(lookup_flags & LOOKUP_FLAG_DIRECTORY_OK)
 594               && inode_is_directory(inode))
 595                 return -EISDIR;
 596
 597         if (stream_name) {
 598                 struct ads_entry *ads_entry;
 599                 u16 ads_idx;
 600                 ads_entry = inode_get_ads_entry(inode, stream_name,
 601                                                 &ads_idx);
 602                 if (ads_entry) {
 603                         stream_idx = ads_idx + 1;
 604                         lte = ads_entry->lte;
 605                         goto out;
 606                 } else {
 607                         return -ENOENT;
 608                 }
 609         } else {
 610                 lte = inode->lte;
 611                 stream_idx = 0;
 612         }
 613 out:
 614         if (dentry_ret)
 615                 *dentry_ret = dentry;
 616         if (lte_ret)
 617                 *lte_ret = lte;
 618         if (stream_idx_ret)
 619                 *stream_idx_ret = stream_idx;
 620         return 0;
 621 }
 622 #endif
 623
 624 /* Resolve an inode's lookup table entries
 625  *
 626  * This replaces the SHA1 hash fields (which are used to lookup an entry in the
 627  * lookup table) with pointers directly to the lookup table entries.  A circular
 628  * linked list of streams sharing the same lookup table entry is created.
 629  *
 630  * This function always succeeds; unresolved lookup table entries are given a
 631  * NULL pointer.
 632  */
 633 void inode_resolve_ltes(struct inode *inode, struct lookup_table *table)
 634 {
 635
 636         if (!inode->resolved) {
 637                 struct lookup_table_entry *lte;
 638                 /* Resolve the default file stream */
 639                 lte = __lookup_resource(table, inode->hash);
 640                 inode->lte = lte;
 641                 inode->resolved = 1;
 642
 643                 /* Resolve the alternate data streams */
 644                 for (u16 i = 0; i < inode->num_ads; i++) {
 645                         struct ads_entry *cur_entry = &inode->ads_entries[i];
 646                         lte = __lookup_resource(table, cur_entry->hash);
 647                         cur_entry->lte = lte;
 648                 }
 649         }
 650 }
 651
 652 void inode_unresolve_ltes(struct inode *inode)
 653 {
 654         if (inode->resolved) {
 655                 if (inode->lte)
 656                         copy_hash(inode->hash, inode->lte->hash);
 657                 else
 658                         zero_out_hash(inode->hash);
 659
 660                 for (u16 i = 0; i < inode->num_ads; i++) {
 661                         if (inode->ads_entries[i].lte)
 662                                 copy_hash(inode->ads_entries[i].hash,
 663                                           inode->ads_entries[i].lte->hash);
 664                         else
 665                                 zero_out_hash(inode->ads_entries[i].hash);
 666                 }
 667                 inode->resolved = 0;
 668         }
 669 }
 670
 671 /*
 672  * Returns the lookup table entry for stream @stream_idx of the inode, where
 673  * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
 674  * corresponds to an alternate data stream.
 675  *
 676  * This works for both resolved and un-resolved dentries.
 677  */
 678 struct lookup_table_entry *
 679 inode_stream_lte(const struct inode *inode, unsigned stream_idx,
 680                  const struct lookup_table *table)
 681 {
 682         if (inode->resolved)
 683                 return inode_stream_lte_resolved(inode, stream_idx);
 684         else
 685                 return inode_stream_lte_unresolved(inode, stream_idx, table);
 686 }
 687
 688
 689 /* Return the lookup table entry for the unnamed data stream of an inode, or
 690  * NULL if there is none.
 691  *
 692  * You'd think this would be easier than it actually is, since the unnamed data
 693  * stream should be the one referenced from the inode itself.  Alas, if there
 694  * are named data streams, Microsoft's "imagex.exe" program will put the unnamed
 695  * data stream in one of the alternate data streams instead of inside the WIM
 696  * dentry itself.  So we need to check the alternate data streams too.
 697  *
 698  * Also, note that a dentry may appear to have more than one unnamed stream, but
 699  * if the SHA1 message digest is all 0's then the corresponding stream does not
 700  * really "count" (this is the case for the inode's own file stream when the
 701  * file stream that should be there is actually in one of the alternate stream
 702  * entries.).  This is despite the fact that we may need to extract such a
 703  * missing entry as an empty file or empty named data stream.
 704  */
 705 struct lookup_table_entry *
 706 inode_unnamed_lte(const struct inode *inode,
 707                   const struct lookup_table *table)
 708 {
 709         if (inode->resolved)
 710                 return inode_unnamed_lte_resolved(inode);
 711         else
 712                 return inode_unnamed_lte_unresolved(inode, table);
 713 }
 714
 715 static int lte_add_stream_size(struct lookup_table_entry *lte,
 716                                void *total_bytes_p)
 717 {
 718         *(u64*)total_bytes_p += lte->resource_entry.size;
 719         return 0;
 720 }
 721
 722 u64 lookup_table_total_stream_size(struct lookup_table *table)
 723 {
 724         u64 total_size = 0;
 725         for_lookup_table_entry(table, lte_add_stream_size, &total_size);
 726         return total_size;
 727 }