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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/lookup_table.h"
  35 #include "wimlib/metadata.h"
  36 #include "wimlib/paths.h"
  37 #include "wimlib/resource.h"
  38 #include "wimlib/util.h"
  39 #include "wimlib/write.h"
  40
  41 #include <errno.h>
  42 #include <stdlib.h>
  43 #ifdef WITH_FUSE
  44 #  include <unistd.h> /* for unlink() */
  45 #endif
  46
  47 struct wim_lookup_table *
  48 new_lookup_table(size_t capacity)
  49 {
  50         struct wim_lookup_table *table;
  51         struct hlist_head *array;
  52
  53         table = CALLOC(1, sizeof(struct wim_lookup_table));
  54         if (table) {
  55                 array = CALLOC(capacity, sizeof(array[0]));
  56                 if (array) {
  57                         table->num_entries = 0;
  58                         table->capacity = capacity;
  59                         table->array = array;
  60                 } else {
  61                         FREE(table);
  62                         table = NULL;
  63                         ERROR("Failed to allocate memory for lookup table "
  64                               "with capacity %zu", capacity);
  65                 }
  66         }
  67         return table;
  68 }
  69
  70 struct wim_lookup_table_entry *
  71 new_lookup_table_entry(void)
  72 {
  73         struct wim_lookup_table_entry *lte;
  74
  75         lte = CALLOC(1, sizeof(struct wim_lookup_table_entry));
  76         if (lte) {
  77                 lte->part_number  = 1;
  78                 lte->refcnt       = 1;
  79         } else {
  80                 ERROR("Out of memory (tried to allocate %zu bytes for "
  81                       "lookup table entry)",
  82                       sizeof(struct wim_lookup_table_entry));
  83         }
  84         return lte;
  85 }
  86
  87 struct wim_lookup_table_entry *
  88 clone_lookup_table_entry(const struct wim_lookup_table_entry *old)
  89 {
  90         struct wim_lookup_table_entry *new;
  91
  92         new = memdup(old, sizeof(struct wim_lookup_table_entry));
  93         if (!new)
  94                 return NULL;
  95
  96         new->extracted_file = NULL;
  97         switch (new->resource_location) {
  98         case RESOURCE_IN_FILE_ON_DISK:
  99 #ifdef __WIN32__
 100         case RESOURCE_WIN32_ENCRYPTED:
 101 #endif
 102 #ifdef WITH_FUSE
 103         case RESOURCE_IN_STAGING_FILE:
 104                 BUILD_BUG_ON((void*)&old->file_on_disk !=
 105                              (void*)&old->staging_file_name);
 106 #endif
 107                 new->file_on_disk = TSTRDUP(old->file_on_disk);
 108                 if (!new->file_on_disk)
 109                         goto out_free;
 110                 break;
 111         case RESOURCE_IN_ATTACHED_BUFFER:
 112                 new->attached_buffer = memdup(old->attached_buffer,
 113                                               wim_resource_size(old));
 114                 if (!new->attached_buffer)
 115                         goto out_free;
 116                 break;
 117 #ifdef WITH_NTFS_3G
 118         case RESOURCE_IN_NTFS_VOLUME:
 119                 if (old->ntfs_loc) {
 120                         struct ntfs_location *loc;
 121                         loc = memdup(old->ntfs_loc, sizeof(struct ntfs_location));
 122                         if (!loc)
 123                                 goto out_free;
 124                         loc->path = NULL;
 125                         loc->stream_name = NULL;
 126                         new->ntfs_loc = loc;
 127                         loc->path = STRDUP(old->ntfs_loc->path);
 128                         if (!loc->path)
 129                                 goto out_free;
 130                         if (loc->stream_name_nchars) {
 131                                 loc->stream_name = memdup(old->ntfs_loc->stream_name,
 132                                                           loc->stream_name_nchars * 2);
 133                                 if (!loc->stream_name)
 134                                         goto out_free;
 135                         }
 136                 }
 137                 break;
 138 #endif
 139         default:
 140                 break;
 141         }
 142         return new;
 143 out_free:
 144         free_lookup_table_entry(new);
 145         return NULL;
 146 }
 147
 148 void
 149 free_lookup_table_entry(struct wim_lookup_table_entry *lte)
 150 {
 151         if (lte) {
 152                 switch (lte->resource_location) {
 153                 case RESOURCE_IN_FILE_ON_DISK:
 154         #ifdef __WIN32__
 155                 case RESOURCE_WIN32_ENCRYPTED:
 156         #endif
 157         #ifdef WITH_FUSE
 158                 case RESOURCE_IN_STAGING_FILE:
 159                         BUILD_BUG_ON((void*)&lte->file_on_disk !=
 160                                      (void*)&lte->staging_file_name);
 161         #endif
 162                 case RESOURCE_IN_ATTACHED_BUFFER:
 163                         BUILD_BUG_ON((void*)&lte->file_on_disk !=
 164                                      (void*)&lte->attached_buffer);
 165                         FREE(lte->file_on_disk);
 166                         break;
 167 #ifdef WITH_NTFS_3G
 168                 case RESOURCE_IN_NTFS_VOLUME:
 169                         if (lte->ntfs_loc) {
 170                                 FREE(lte->ntfs_loc->path);
 171                                 FREE(lte->ntfs_loc->stream_name);
 172                                 FREE(lte->ntfs_loc);
 173                         }
 174                         break;
 175 #endif
 176                 default:
 177                         break;
 178                 }
 179                 FREE(lte);
 180         }
 181 }
 182
 183 static int
 184 do_free_lookup_table_entry(struct wim_lookup_table_entry *entry, void *ignore)
 185 {
 186         free_lookup_table_entry(entry);
 187         return 0;
 188 }
 189
 190
 191 void
 192 free_lookup_table(struct wim_lookup_table *table)
 193 {
 194         DEBUG2("Freeing lookup table");
 195         if (table) {
 196                 if (table->array) {
 197                         for_lookup_table_entry(table,
 198                                                do_free_lookup_table_entry,
 199                                                NULL);
 200                         FREE(table->array);
 201                 }
 202                 FREE(table);
 203         }
 204 }
 205
 206 /*
 207  * Inserts an entry into the lookup table.
 208  *
 209  * @table:      A pointer to the lookup table.
 210  * @lte:        A pointer to the entry to insert.
 211  */
 212 void
 213 lookup_table_insert(struct wim_lookup_table *table,
 214                     struct wim_lookup_table_entry *lte)
 215 {
 216         size_t i = lte->hash_short % table->capacity;
 217         hlist_add_head(&lte->hash_list, &table->array[i]);
 218
 219         /* XXX Make the table grow when too many entries have been inserted. */
 220         table->num_entries++;
 221 }
 222
 223 static void
 224 finalize_lte(struct wim_lookup_table_entry *lte)
 225 {
 226         #ifdef WITH_FUSE
 227         if (lte->resource_location == RESOURCE_IN_STAGING_FILE) {
 228                 unlink(lte->staging_file_name);
 229                 list_del(&lte->unhashed_list);
 230         }
 231         #endif
 232         free_lookup_table_entry(lte);
 233 }
 234
 235 /* Decrements the reference count for the lookup table entry @lte.  If its
 236  * reference count reaches 0, it is unlinked from the lookup table.  If,
 237  * furthermore, the entry has no opened file descriptors associated with it, the
 238  * entry is freed.  */
 239 void
 240 lte_decrement_refcnt(struct wim_lookup_table_entry *lte,
 241                      struct wim_lookup_table *table)
 242 {
 243         wimlib_assert(lte != NULL);
 244         wimlib_assert(lte->refcnt != 0);
 245         if (--lte->refcnt == 0) {
 246                 if (lte->unhashed)
 247                         list_del(&lte->unhashed_list);
 248                 else
 249                         lookup_table_unlink(table, lte);
 250         #ifdef WITH_FUSE
 251                 if (lte->num_opened_fds == 0)
 252         #endif
 253                         finalize_lte(lte);
 254         }
 255 }
 256
 257 #ifdef WITH_FUSE
 258 void
 259 lte_decrement_num_opened_fds(struct wim_lookup_table_entry *lte)
 260 {
 261         if (lte->num_opened_fds != 0)
 262                 if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
 263                         finalize_lte(lte);
 264 }
 265 #endif
 266
 267 /* Calls a function on all the entries in the WIM lookup table.  Stop early and
 268  * return nonzero if any call to the function returns nonzero. */
 269 int
 270 for_lookup_table_entry(struct wim_lookup_table *table,
 271                        int (*visitor)(struct wim_lookup_table_entry *, void *),
 272                        void *arg)
 273 {
 274         struct wim_lookup_table_entry *lte;
 275         struct hlist_node *pos, *tmp;
 276         int ret;
 277
 278         for (size_t i = 0; i < table->capacity; i++) {
 279                 hlist_for_each_entry_safe(lte, pos, tmp, &table->array[i],
 280                                           hash_list)
 281                 {
 282                         wimlib_assert2(!(lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA));
 283                         ret = visitor(lte, arg);
 284                         if (ret)
 285                                 return ret;
 286                 }
 287         }
 288         return 0;
 289 }
 290
 291 int
 292 cmp_streams_by_wim_position(const void *p1, const void *p2)
 293 {
 294         const struct wim_lookup_table_entry *lte1, *lte2;
 295         lte1 = *(const struct wim_lookup_table_entry**)p1;
 296         lte2 = *(const struct wim_lookup_table_entry**)p2;
 297         if (lte1->resource_entry.offset < lte2->resource_entry.offset)
 298                 return -1;
 299         else if (lte1->resource_entry.offset > lte2->resource_entry.offset)
 300                 return 1;
 301         else
 302                 return 0;
 303 }
 304
 305 static int
 306 add_lte_to_array(struct wim_lookup_table_entry *lte,
 307                  void *_pp)
 308 {
 309         struct wim_lookup_table_entry ***pp = _pp;
 310         *(*pp)++ = lte;
 311         return 0;
 312 }
 313
 314 /* Iterate through the lookup table entries, but first sort them by stream
 315  * offset in the WIM.  Caution: this is intended to be used when the stream
 316  * offset field has actually been set. */
 317 int
 318 for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
 319                                   int (*visitor)(struct wim_lookup_table_entry *,
 320                                                  void *),
 321                                   void *arg)
 322 {
 323         struct wim_lookup_table_entry **lte_array, **p;
 324         size_t num_streams = table->num_entries;
 325         int ret;
 326
 327         lte_array = MALLOC(num_streams * sizeof(lte_array[0]));
 328         if (!lte_array)
 329                 return WIMLIB_ERR_NOMEM;
 330         p = lte_array;
 331         for_lookup_table_entry(table, add_lte_to_array, &p);
 332
 333         wimlib_assert(p == lte_array + num_streams);
 334
 335         qsort(lte_array, num_streams, sizeof(lte_array[0]),
 336               cmp_streams_by_wim_position);
 337         ret = 0;
 338         for (size_t i = 0; i < num_streams; i++) {
 339                 ret = visitor(lte_array[i], arg);
 340                 if (ret)
 341                         break;
 342         }
 343         FREE(lte_array);
 344         return ret;
 345 }
 346
 347 /* On-disk format of a WIM lookup table entry (stream entry). */
 348 struct wim_lookup_table_entry_disk {
 349         /* Location, offset, compression status, and metadata status of the
 350          * stream. */
 351         struct resource_entry_disk resource_entry;
 352
 353         /* Which part of the split WIM this stream is in; indexed from 1. */
 354         le16 part_number;
 355
 356         /* Reference count of this stream over all WIM images. */
 357         le32 refcnt;
 358
 359         /* SHA1 message digest of the uncompressed data of this stream, or
 360          * optionally all zeroes if this stream is of zero length. */
 361         u8 hash[SHA1_HASH_SIZE];
 362 } _packed_attribute;
 363
 364 #define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
 365
 366 void
 367 lte_init_wim(struct wim_lookup_table_entry *lte, WIMStruct *wim)
 368 {
 369         lte->resource_location = RESOURCE_IN_WIM;
 370         lte->wim = wim;
 371         if (lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
 372                 lte->compression_type = wim->compression_type;
 373         else
 374                 lte->compression_type = WIMLIB_COMPRESSION_TYPE_NONE;
 375
 376         if (wim_is_pipable(wim))
 377                 lte->is_pipable = 1;
 378 }
 379
 380 /*
 381  * Reads the lookup table from a WIM file.
 382  *
 383  * Saves lookup table entries for non-metadata streams in a hash table, and
 384  * saves the metadata entry for each image in a special per-image location (the
 385  * image_metadata array).
 386  *
 387  * Return values:
 388  *      WIMLIB_ERR_SUCCESS (0)
 389  *      WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY
 390  *      WIMLIB_ERR_RESOURCE_NOT_FOUND
 391  */
 392 int
 393 read_wim_lookup_table(WIMStruct *wim)
 394 {
 395         int ret;
 396         size_t i;
 397         size_t num_entries;
 398         struct wim_lookup_table *table;
 399         struct wim_lookup_table_entry *cur_entry, *duplicate_entry;
 400         struct wim_lookup_table_entry_disk *buf;
 401
 402         BUILD_BUG_ON(sizeof(struct wim_lookup_table_entry_disk) !=
 403                      WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE);
 404
 405         DEBUG("Reading lookup table: offset %"PRIu64", size %"PRIu64"",
 406               wim->hdr.lookup_table_res_entry.offset,
 407               wim->hdr.lookup_table_res_entry.size);
 408
 409         /* Calculate number of entries in the lookup table.  */
 410         num_entries = wim->hdr.lookup_table_res_entry.size /
 411                       sizeof(struct wim_lookup_table_entry_disk);
 412
 413
 414         /* Read the lookup table into a buffer.  */
 415         ret = res_entry_to_data(&wim->hdr.lookup_table_res_entry, wim,
 416                                 (void**)&buf);
 417         if (ret)
 418                 goto out;
 419
 420         /* Allocate hash table.  */
 421         table = new_lookup_table(num_entries * 2 + 1);
 422         if (!table) {
 423                 ERROR("Not enough memory to read lookup table.");
 424                 ret = WIMLIB_ERR_NOMEM;
 425                 goto out_free_buf;
 426         }
 427
 428         /* Allocate and initalize `struct wim_lookup_table_entry's from the
 429          * on-disk lookup table.  */
 430         wim->current_image = 0;
 431         for (i = 0; i < num_entries; i++) {
 432                 const struct wim_lookup_table_entry_disk *disk_entry = &buf[i];
 433
 434                 cur_entry = new_lookup_table_entry();
 435                 if (!cur_entry) {
 436                         ERROR("Not enough memory to read lookup table.");
 437                         ret = WIMLIB_ERR_NOMEM;
 438                         goto out_free_lookup_table;
 439                 }
 440
 441                 cur_entry->wim = wim;
 442                 cur_entry->resource_location = RESOURCE_IN_WIM;
 443                 get_resource_entry(&disk_entry->resource_entry, &cur_entry->resource_entry);
 444                 cur_entry->part_number = le16_to_cpu(disk_entry->part_number);
 445                 cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
 446                 copy_hash(cur_entry->hash, disk_entry->hash);
 447                 lte_init_wim(cur_entry, wim);
 448
 449                 if (cur_entry->part_number != wim->hdr.part_number) {
 450                         WARNING("A lookup table entry in part %hu of the WIM "
 451                                 "points to part %hu (ignoring it)",
 452                                 wim->hdr.part_number, cur_entry->part_number);
 453                         free_lookup_table_entry(cur_entry);
 454                         continue;
 455                 }
 456
 457                 if (is_zero_hash(cur_entry->hash)) {
 458                         WARNING("The WIM lookup table contains an entry with a "
 459                                 "SHA1 message digest of all 0's (ignoring it)");
 460                         free_lookup_table_entry(cur_entry);
 461                         continue;
 462                 }
 463
 464                 if (!(cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
 465                     && (cur_entry->resource_entry.size !=
 466                         cur_entry->resource_entry.original_size))
 467                 {
 468                         if (wimlib_print_errors) {
 469                                 WARNING("Found uncompressed resource with "
 470                                         "original size (%"PRIu64") not the same "
 471                                         "as compressed size (%"PRIu64")",
 472                                         cur_entry->resource_entry.original_size,
 473                                         cur_entry->resource_entry.size);
 474                                 if (cur_entry->resource_entry.original_size) {
 475                                         WARNING("Overriding compressed size with original size.");
 476                                         cur_entry->resource_entry.size =
 477                                                 cur_entry->resource_entry.original_size;
 478                                 } else {
 479                                         WARNING("Overriding original size with compressed size");
 480                                         cur_entry->resource_entry.original_size =
 481                                                 cur_entry->resource_entry.size;
 482                                 }
 483                         }
 484                 }
 485
 486                 if (cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) {
 487                         /* Lookup table entry for a metadata resource */
 488                         if (cur_entry->refcnt != 1) {
 489                                 if (wimlib_print_errors) {
 490                                         ERROR("Found metadata resource with refcnt != 1:");
 491                                         print_lookup_table_entry(cur_entry, stderr);
 492                                 }
 493                                 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
 494                                 goto out_free_cur_entry;
 495                         }
 496
 497                         if (wim->hdr.part_number != 1) {
 498                                 WARNING("Ignoring metadata resource found in a "
 499                                         "non-first part of the split WIM");
 500                                 free_lookup_table_entry(cur_entry);
 501                                 continue;
 502                         }
 503                         if (wim->current_image == wim->hdr.image_count) {
 504                                 WARNING("The WIM header says there are %u images "
 505                                         "in the WIM, but we found more metadata "
 506                                         "resources than this (ignoring the extra)",
 507                                         wim->hdr.image_count);
 508                                 free_lookup_table_entry(cur_entry);
 509                                 continue;
 510                         }
 511
 512                         /* Notice very carefully:  We are assigning the metadata
 513                          * resources in the exact order mirrored by their lookup
 514                          * table entries on disk, which is the behavior of
 515                          * Microsoft's software.  In particular, this overrides
 516                          * the actual locations of the metadata resources
 517                          * themselves in the WIM file as well as any information
 518                          * written in the XML data. */
 519                         DEBUG("Found metadata resource for image %u at "
 520                               "offset %"PRIu64".",
 521                               wim->current_image + 1,
 522                               cur_entry->resource_entry.offset);
 523                         wim->image_metadata[
 524                                 wim->current_image++]->metadata_lte = cur_entry;
 525                 } else {
 526                         /* Lookup table entry for a stream that is not a
 527                          * metadata resource */
 528                         duplicate_entry = __lookup_resource(table, cur_entry->hash);
 529                         if (duplicate_entry) {
 530                                 if (wimlib_print_errors) {
 531                                         WARNING("The WIM lookup table contains two entries with the "
 532                                               "same SHA1 message digest!");
 533                                         WARNING("The first entry is:");
 534                                         print_lookup_table_entry(duplicate_entry, stderr);
 535                                         WARNING("The second entry is:");
 536                                         print_lookup_table_entry(cur_entry, stderr);
 537                                 }
 538                                 free_lookup_table_entry(cur_entry);
 539                                 continue;
 540                         } else {
 541                                 lookup_table_insert(table, cur_entry);
 542                         }
 543                 }
 544         }
 545
 546         if (wim->hdr.part_number == 1 && wim->current_image != wim->hdr.image_count) {
 547                 WARNING("The header of \"%"TS"\" says there are %u images in\n"
 548                         "          the WIM, but we only found %d metadata resources!  Acting as if\n"
 549                         "          the header specified only %d images instead.",
 550                         wim->filename, wim->hdr.image_count,
 551                         wim->current_image, wim->current_image);
 552                 for (int i = wim->current_image; i < wim->hdr.image_count; i++)
 553                         put_image_metadata(wim->image_metadata[i], NULL);
 554                 wim->hdr.image_count = wim->current_image;
 555         }
 556         DEBUG("Done reading lookup table.");
 557         wim->lookup_table = table;
 558         ret = 0;
 559         goto out_free_buf;
 560 out_free_cur_entry:
 561         FREE(cur_entry);
 562 out_free_lookup_table:
 563         free_lookup_table(table);
 564 out_free_buf:
 565         FREE(buf);
 566 out:
 567         wim->current_image = 0;
 568         return ret;
 569 }
 570
 571
 572 static void
 573 write_wim_lookup_table_entry(const struct wim_lookup_table_entry *lte,
 574                              struct wim_lookup_table_entry_disk *disk_entry)
 575 {
 576         put_resource_entry(&lte->output_resource_entry, &disk_entry->resource_entry);
 577         disk_entry->part_number = cpu_to_le16(lte->part_number);
 578         disk_entry->refcnt = cpu_to_le32(lte->out_refcnt);
 579         copy_hash(disk_entry->hash, lte->hash);
 580 }
 581
 582 static int
 583 write_wim_lookup_table_from_stream_list(struct list_head *stream_list,
 584                                         struct filedes *out_fd,
 585                                         struct resource_entry *out_res_entry,
 586                                         int write_resource_flags)
 587 {
 588         size_t table_size;
 589         struct wim_lookup_table_entry *lte;
 590         struct wim_lookup_table_entry_disk *table_buf;
 591         struct wim_lookup_table_entry_disk *table_buf_ptr;
 592         int ret;
 593
 594         table_size = 0;
 595         list_for_each_entry(lte, stream_list, lookup_table_list)
 596                 table_size += sizeof(struct wim_lookup_table_entry_disk);
 597
 598         DEBUG("Writing WIM lookup table (size=%zu, offset=%"PRIu64")",
 599               table_size, out_fd->offset);
 600
 601         table_buf = MALLOC(table_size);
 602         if (!table_buf) {
 603                 ERROR("Failed to allocate %zu bytes for temporary lookup table",
 604                       table_size);
 605                 return WIMLIB_ERR_NOMEM;
 606         }
 607         table_buf_ptr = table_buf;
 608         list_for_each_entry(lte, stream_list, lookup_table_list)
 609                 write_wim_lookup_table_entry(lte, table_buf_ptr++);
 610
 611         /* Write the lookup table uncompressed.  Although wimlib can handle a
 612          * compressed lookup table, MS software cannot.  */
 613         ret = write_wim_resource_from_buffer(table_buf,
 614                                              table_size,
 615                                              WIM_RESHDR_FLAG_METADATA,
 616                                              out_fd,
 617                                              WIMLIB_COMPRESSION_TYPE_NONE,
 618                                              out_res_entry,
 619                                              NULL,
 620                                              write_resource_flags);
 621         FREE(table_buf);
 622         return ret;
 623 }
 624
 625 static int
 626 append_lookup_table_entry(struct wim_lookup_table_entry *lte, void *_list)
 627 {
 628         if (lte->out_refcnt != 0)
 629                 list_add_tail(&lte->lookup_table_list, (struct list_head*)_list);
 630         return 0;
 631 }
 632
 633 int
 634 write_wim_lookup_table(WIMStruct *wim, int image, int write_flags,
 635                        struct resource_entry *out_res_entry,
 636                        struct list_head *stream_list_override)
 637 {
 638         int write_resource_flags;
 639         struct list_head _stream_list;
 640         struct list_head *stream_list;
 641
 642         if (stream_list_override) {
 643                 stream_list = stream_list_override;
 644         } else {
 645                 stream_list = &_stream_list;
 646                 INIT_LIST_HEAD(stream_list);
 647         }
 648
 649         if (!(write_flags & WIMLIB_WRITE_FLAG_NO_METADATA)) {
 650                 int start_image;
 651                 int end_image;
 652
 653                 if (image == WIMLIB_ALL_IMAGES) {
 654                         start_image = 1;
 655                         end_image = wim->hdr.image_count;
 656                 } else {
 657                         start_image = image;
 658                         end_image = image;
 659                 }
 660
 661                 /* Push metadata resource lookup table entries onto the front of
 662                  * the list in reverse order, so that they're written in order.
 663                  */
 664                 for (int i = end_image; i >= start_image; i--) {
 665                         struct wim_lookup_table_entry *metadata_lte;
 666
 667                         metadata_lte = wim->image_metadata[i - 1]->metadata_lte;
 668                         metadata_lte->out_refcnt = 1;
 669                         metadata_lte->part_number = wim->hdr.part_number;
 670                         metadata_lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_METADATA;
 671
 672                         list_add(&metadata_lte->lookup_table_list, stream_list);
 673                 }
 674         }
 675
 676         /* Append additional lookup table entries that have out_refcnt != 0.  */
 677         if (!stream_list_override) {
 678                 for_lookup_table_entry(wim->lookup_table,
 679                                        append_lookup_table_entry, stream_list);
 680         }
 681
 682         write_resource_flags = 0;
 683         if (write_flags & WIMLIB_WRITE_FLAG_PIPABLE)
 684                 write_resource_flags |= WIMLIB_WRITE_RESOURCE_FLAG_PIPABLE;
 685         return write_wim_lookup_table_from_stream_list(stream_list,
 686                                                        &wim->out_fd,
 687                                                        out_res_entry,
 688                                                        write_resource_flags);
 689 }
 690
 691
 692 int
 693 lte_zero_real_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
 694 {
 695         lte->real_refcnt = 0;
 696         return 0;
 697 }
 698
 699 int
 700 lte_zero_out_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
 701 {
 702         lte->out_refcnt = 0;
 703         return 0;
 704 }
 705
 706 int
 707 lte_free_extracted_file(struct wim_lookup_table_entry *lte, void *_ignore)
 708 {
 709         if (lte->extracted_file != NULL) {
 710                 FREE(lte->extracted_file);
 711                 lte->extracted_file = NULL;
 712         }
 713         return 0;
 714 }
 715
 716 void
 717 print_lookup_table_entry(const struct wim_lookup_table_entry *lte, FILE *out)
 718 {
 719         if (!lte) {
 720                 tputc(T('\n'), out);
 721                 return;
 722         }
 723         tfprintf(out, T("Offset            = %"PRIu64" bytes\n"),
 724                  lte->resource_entry.offset);
 725
 726         tfprintf(out, T("Size              = %"PRIu64" bytes\n"),
 727                  (u64)lte->resource_entry.size);
 728
 729         tfprintf(out, T("Original size     = %"PRIu64" bytes\n"),
 730                  lte->resource_entry.original_size);
 731
 732         tfprintf(out, T("Part Number       = %hu\n"), lte->part_number);
 733         tfprintf(out, T("Reference Count   = %u\n"), lte->refcnt);
 734
 735         if (lte->unhashed) {
 736                 tfprintf(out, T("(Unhashed: inode %p, stream_id = %u)\n"),
 737                          lte->back_inode, lte->back_stream_id);
 738         } else {
 739                 tfprintf(out, T("Hash              = 0x"));
 740                 print_hash(lte->hash, out);
 741                 tputc(T('\n'), out);
 742         }
 743
 744         tfprintf(out, T("Flags             = "));
 745         u8 flags = lte->resource_entry.flags;
 746         if (flags & WIM_RESHDR_FLAG_COMPRESSED)
 747                 tfputs(T("WIM_RESHDR_FLAG_COMPRESSED, "), out);
 748         if (flags & WIM_RESHDR_FLAG_FREE)
 749                 tfputs(T("WIM_RESHDR_FLAG_FREE, "), out);
 750         if (flags & WIM_RESHDR_FLAG_METADATA)
 751                 tfputs(T("WIM_RESHDR_FLAG_METADATA, "), out);
 752         if (flags & WIM_RESHDR_FLAG_SPANNED)
 753                 tfputs(T("WIM_RESHDR_FLAG_SPANNED, "), out);
 754         tputc(T('\n'), out);
 755         switch (lte->resource_location) {
 756         case RESOURCE_IN_WIM:
 757                 if (lte->wim->filename) {
 758                         tfprintf(out, T("WIM file          = `%"TS"'\n"),
 759                                  lte->wim->filename);
 760                 }
 761                 break;
 762 #ifdef __WIN32__
 763         case RESOURCE_WIN32_ENCRYPTED:
 764 #endif
 765         case RESOURCE_IN_FILE_ON_DISK:
 766                 tfprintf(out, T("File on Disk      = `%"TS"'\n"),
 767                          lte->file_on_disk);
 768                 break;
 769 #ifdef WITH_FUSE
 770         case RESOURCE_IN_STAGING_FILE:
 771                 tfprintf(out, T("Staging File      = `%"TS"'\n"),
 772                                 lte->staging_file_name);
 773                 break;
 774 #endif
 775         default:
 776                 break;
 777         }
 778         tputc(T('\n'), out);
 779 }
 780
 781 void
 782 lte_to_wimlib_resource_entry(const struct wim_lookup_table_entry *lte,
 783                              struct wimlib_resource_entry *wentry)
 784 {
 785         wentry->uncompressed_size = lte->resource_entry.original_size;
 786         wentry->compressed_size = lte->resource_entry.size;
 787         wentry->offset = lte->resource_entry.offset;
 788         copy_hash(wentry->sha1_hash, lte->hash);
 789         wentry->part_number = lte->part_number;
 790         wentry->reference_count = lte->refcnt;
 791         wentry->is_compressed = (lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED) != 0;
 792         wentry->is_metadata = (lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) != 0;
 793         wentry->is_free = (lte->resource_entry.flags & WIM_RESHDR_FLAG_FREE) != 0;
 794         wentry->is_spanned = (lte->resource_entry.flags & WIM_RESHDR_FLAG_SPANNED) != 0;
 795 }
 796
 797 struct iterate_lte_context {
 798         wimlib_iterate_lookup_table_callback_t cb;
 799         void *user_ctx;
 800 };
 801
 802 static int
 803 do_iterate_lte(struct wim_lookup_table_entry *lte, void *_ctx)
 804 {
 805         struct iterate_lte_context *ctx = _ctx;
 806         struct wimlib_resource_entry entry;
 807
 808         lte_to_wimlib_resource_entry(lte, &entry);
 809         return (*ctx->cb)(&entry, ctx->user_ctx);
 810 }
 811
 812 /* API function documented in wimlib.h  */
 813 WIMLIBAPI int
 814 wimlib_iterate_lookup_table(WIMStruct *wim, int flags,
 815                             wimlib_iterate_lookup_table_callback_t cb,
 816                             void *user_ctx)
 817 {
 818         struct iterate_lte_context ctx = {
 819                 .cb = cb,
 820                 .user_ctx = user_ctx,
 821         };
 822         if (wim->hdr.part_number == 1) {
 823                 int ret;
 824                 for (int i = 0; i < wim->hdr.image_count; i++) {
 825                         ret = do_iterate_lte(wim->image_metadata[i]->metadata_lte,
 826                                              &ctx);
 827                         if (ret)
 828                                 return ret;
 829                 }
 830         }
 831         return for_lookup_table_entry(wim->lookup_table, do_iterate_lte, &ctx);
 832 }
 833
 834 static int
 835 do_print_lookup_table_entry(struct wim_lookup_table_entry *lte, void *fp)
 836 {
 837         print_lookup_table_entry(lte, (FILE*)fp);
 838         return 0;
 839 }
 840
 841 /* API function documented in wimlib.h  */
 842 WIMLIBAPI void
 843 wimlib_print_lookup_table(WIMStruct *wim)
 844 {
 845         for (int i = 0; i < wim->hdr.image_count; i++)
 846                 print_lookup_table_entry(wim->image_metadata[i]->metadata_lte, stdout);
 847         for_lookup_table_entry(wim->lookup_table,
 848                                do_print_lookup_table_entry,
 849                                stdout);
 850 }
 851
 852 /* Given a SHA1 message digest, return the corresponding entry in the WIM's
 853  * lookup table, or NULL if there is none.  */
 854 struct wim_lookup_table_entry *
 855 __lookup_resource(const struct wim_lookup_table *table, const u8 hash[])
 856 {
 857         size_t i;
 858         struct wim_lookup_table_entry *lte;
 859         struct hlist_node *pos;
 860
 861         wimlib_assert(table != NULL);
 862         wimlib_assert(hash != NULL);
 863
 864         i = *(size_t*)hash % table->capacity;
 865         hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
 866                 if (hashes_equal(hash, lte->hash))
 867                         return lte;
 868         return NULL;
 869 }
 870
 871 #ifdef WITH_FUSE
 872 /*
 873  * Finds the dentry, lookup table entry, and stream index for a WIM file stream,
 874  * given a path name.
 875  *
 876  * This is only for pre-resolved inodes.
 877  */
 878 int
 879 lookup_resource(WIMStruct *wim,
 880                 const tchar *path,
 881                 int lookup_flags,
 882                 struct wim_dentry **dentry_ret,
 883                 struct wim_lookup_table_entry **lte_ret,
 884                 u16 *stream_idx_ret)
 885 {
 886         struct wim_dentry *dentry;
 887         struct wim_lookup_table_entry *lte;
 888         u16 stream_idx;
 889         const tchar *stream_name = NULL;
 890         struct wim_inode *inode;
 891         tchar *p = NULL;
 892
 893         if (lookup_flags & LOOKUP_FLAG_ADS_OK) {
 894                 stream_name = path_stream_name(path);
 895                 if (stream_name) {
 896                         p = (tchar*)stream_name - 1;
 897                         *p = T('\0');
 898                 }
 899         }
 900
 901         dentry = get_dentry(wim, path);
 902         if (p)
 903                 *p = T(':');
 904         if (!dentry)
 905                 return -errno;
 906
 907         inode = dentry->d_inode;
 908
 909         if (!inode->i_resolved)
 910                 if (inode_resolve_ltes(inode, wim->lookup_table, false))
 911                         return -EIO;
 912
 913         if (!(lookup_flags & LOOKUP_FLAG_DIRECTORY_OK)
 914               && inode_is_directory(inode))
 915                 return -EISDIR;
 916
 917         if (stream_name) {
 918                 struct wim_ads_entry *ads_entry;
 919                 u16 ads_idx;
 920                 ads_entry = inode_get_ads_entry(inode, stream_name,
 921                                                 &ads_idx);
 922                 if (ads_entry) {
 923                         stream_idx = ads_idx + 1;
 924                         lte = ads_entry->lte;
 925                         goto out;
 926                 } else {
 927                         return -ENOENT;
 928                 }
 929         } else {
 930                 lte = inode->i_lte;
 931                 stream_idx = 0;
 932         }
 933 out:
 934         if (dentry_ret)
 935                 *dentry_ret = dentry;
 936         if (lte_ret)
 937                 *lte_ret = lte;
 938         if (stream_idx_ret)
 939                 *stream_idx_ret = stream_idx;
 940         return 0;
 941 }
 942 #endif
 943
 944 /*
 945  * Resolve an inode's lookup table entries.
 946  *
 947  * This replaces the SHA1 hash fields (which are used to lookup an entry in the
 948  * lookup table) with pointers directly to the lookup table entries.
 949  *
 950  * If @force is %false:
 951  *      If any needed SHA1 message digests are not found in the lookup table,
 952  *      WIMLIB_ERR_RESOURCE_NOT_FOUND is returned and the inode is left
 953  *      unmodified.
 954  * If @force is %true:
 955  *      If any needed SHA1 message digests are not found in the lookup table,
 956  *      new entries are allocated and inserted into the lookup table.
 957  */
 958 int
 959 inode_resolve_ltes(struct wim_inode *inode, struct wim_lookup_table *table,
 960                    bool force)
 961 {
 962         const u8 *hash;
 963
 964         if (!inode->i_resolved) {
 965                 struct wim_lookup_table_entry *lte, *ads_lte;
 966
 967                 /* Resolve the default file stream */
 968                 lte = NULL;
 969                 hash = inode->i_hash;
 970                 if (!is_zero_hash(hash)) {
 971                         lte = __lookup_resource(table, hash);
 972                         if (!lte) {
 973                                 if (force) {
 974                                         lte = new_lookup_table_entry();
 975                                         if (!lte)
 976                                                 return WIMLIB_ERR_NOMEM;
 977                                         copy_hash(lte->hash, hash);
 978                                         lookup_table_insert(table, lte);
 979                                 } else {
 980                                         goto resource_not_found;
 981                                 }
 982                         }
 983                 }
 984
 985                 /* Resolve the alternate data streams */
 986                 struct wim_lookup_table_entry *ads_ltes[inode->i_num_ads];
 987                 for (u16 i = 0; i < inode->i_num_ads; i++) {
 988                         struct wim_ads_entry *cur_entry;
 989
 990                         ads_lte = NULL;
 991                         cur_entry = &inode->i_ads_entries[i];
 992                         hash = cur_entry->hash;
 993                         if (!is_zero_hash(hash)) {
 994                                 ads_lte = __lookup_resource(table, hash);
 995                                 if (!ads_lte) {
 996                                         if (force) {
 997                                                 ads_lte = new_lookup_table_entry();
 998                                                 if (!ads_lte)
 999                                                         return WIMLIB_ERR_NOMEM;
1000                                                 copy_hash(ads_lte->hash, hash);
1001                                                 lookup_table_insert(table, ads_lte);
1002                                         } else {
1003                                                 goto resource_not_found;
1004                                         }
1005                                 }
1006                         }
1007                         ads_ltes[i] = ads_lte;
1008                 }
1009                 inode->i_lte = lte;
1010                 for (u16 i = 0; i < inode->i_num_ads; i++)
1011                         inode->i_ads_entries[i].lte = ads_ltes[i];
1012                 inode->i_resolved = 1;
1013         }
1014         return 0;
1015 resource_not_found:
1016         if (wimlib_print_errors) {
1017                 ERROR("\"%"TS"\": resource not found", inode_first_full_path(inode));
1018                 tfprintf(stderr, T("        SHA-1 message digest of missing resource:\n        "));
1019                 print_hash(hash, stderr);
1020                 tputc(T('\n'), stderr);
1021         }
1022         return WIMLIB_ERR_RESOURCE_NOT_FOUND;
1023 }
1024
1025 void
1026 inode_unresolve_ltes(struct wim_inode *inode)
1027 {
1028         if (inode->i_resolved) {
1029                 if (inode->i_lte)
1030                         copy_hash(inode->i_hash, inode->i_lte->hash);
1031                 else
1032                         zero_out_hash(inode->i_hash);
1033
1034                 for (u16 i = 0; i < inode->i_num_ads; i++) {
1035                         if (inode->i_ads_entries[i].lte)
1036                                 copy_hash(inode->i_ads_entries[i].hash,
1037                                           inode->i_ads_entries[i].lte->hash);
1038                         else
1039                                 zero_out_hash(inode->i_ads_entries[i].hash);
1040                 }
1041                 inode->i_resolved = 0;
1042         }
1043 }
1044
1045 /*
1046  * Returns the lookup table entry for stream @stream_idx of the inode, where
1047  * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
1048  * corresponds to an alternate data stream.
1049  *
1050  * This works for both resolved and un-resolved inodes.
1051  */
1052 struct wim_lookup_table_entry *
1053 inode_stream_lte(const struct wim_inode *inode, unsigned stream_idx,
1054                  const struct wim_lookup_table *table)
1055 {
1056         if (inode->i_resolved)
1057                 return inode_stream_lte_resolved(inode, stream_idx);
1058         else
1059                 return inode_stream_lte_unresolved(inode, stream_idx, table);
1060 }
1061
1062 struct wim_lookup_table_entry *
1063 inode_unnamed_lte_resolved(const struct wim_inode *inode)
1064 {
1065         wimlib_assert(inode->i_resolved);
1066         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1067                 if (inode_stream_name_nbytes(inode, i) == 0 &&
1068                     !is_zero_hash(inode_stream_hash_resolved(inode, i)))
1069                 {
1070                         return inode_stream_lte_resolved(inode, i);
1071                 }
1072         }
1073         return NULL;
1074 }
1075
1076 struct wim_lookup_table_entry *
1077 inode_unnamed_lte_unresolved(const struct wim_inode *inode,
1078                              const struct wim_lookup_table *table)
1079 {
1080         wimlib_assert(!inode->i_resolved);
1081         for (unsigned i = 0; i <= inode->i_num_ads; i++) {
1082                 if (inode_stream_name_nbytes(inode, i) == 0 &&
1083                     !is_zero_hash(inode_stream_hash_unresolved(inode, i)))
1084                 {
1085                         return inode_stream_lte_unresolved(inode, i, table);
1086                 }
1087         }
1088         return NULL;
1089 }
1090
1091 /* Return the lookup table entry for the unnamed data stream of an inode, or
1092  * NULL if there is none.
1093  *
1094  * You'd think this would be easier than it actually is, since the unnamed data
1095  * stream should be the one referenced from the inode itself.  Alas, if there
1096  * are named data streams, Microsoft's "imagex.exe" program will put the unnamed
1097  * data stream in one of the alternate data streams instead of inside the WIM
1098  * dentry itself.  So we need to check the alternate data streams too.
1099  *
1100  * Also, note that a dentry may appear to have more than one unnamed stream, but
1101  * if the SHA1 message digest is all 0's then the corresponding stream does not
1102  * really "count" (this is the case for the inode's own file stream when the
1103  * file stream that should be there is actually in one of the alternate stream
1104  * entries.).  This is despite the fact that we may need to extract such a
1105  * missing entry as an empty file or empty named data stream.
1106  */
1107 struct wim_lookup_table_entry *
1108 inode_unnamed_lte(const struct wim_inode *inode,
1109                   const struct wim_lookup_table *table)
1110 {
1111         if (inode->i_resolved)
1112                 return inode_unnamed_lte_resolved(inode);
1113         else
1114                 return inode_unnamed_lte_unresolved(inode, table);
1115 }
1116
1117 static int
1118 lte_add_stream_size(struct wim_lookup_table_entry *lte, void *total_bytes_p)
1119 {
1120         *(u64*)total_bytes_p += lte->resource_entry.size;
1121         return 0;
1122 }
1123
1124 u64
1125 lookup_table_total_stream_size(struct wim_lookup_table *table)
1126 {
1127         u64 total_size = 0;
1128         for_lookup_table_entry(table, lte_add_stream_size, &total_size);
1129         return total_size;
1130 }
1131
1132 struct wim_lookup_table_entry **
1133 retrieve_lte_pointer(struct wim_lookup_table_entry *lte)
1134 {
1135         wimlib_assert(lte->unhashed);
1136         struct wim_inode *inode = lte->back_inode;
1137         u32 stream_id = lte->back_stream_id;
1138         if (stream_id == 0)
1139                 return &inode->i_lte;
1140         else
1141                 for (u16 i = 0; i < inode->i_num_ads; i++)
1142                         if (inode->i_ads_entries[i].stream_id == stream_id)
1143                                 return &inode->i_ads_entries[i].lte;
1144         wimlib_assert(0);
1145         return NULL;
1146 }
1147
1148 /* Calculate the SHA1 message digest of a stream and move it from the list of
1149  * unhashed streams to the stream lookup table, possibly joining it with an
1150  * existing lookup table entry for an identical stream.
1151  *
1152  * @lte:  An unhashed lookup table entry.
1153  * @lookup_table:  Lookup table for the WIM.
1154  * @lte_ret:  On success, write a pointer to the resulting lookup table
1155  *            entry to this location.  This will be the same as @lte
1156  *            if it was inserted into the lookup table, or different if
1157  *            a duplicate stream was found.
1158  *
1159  * Returns 0 on success; nonzero if there is an error reading the stream.
1160  */
1161 int
1162 hash_unhashed_stream(struct wim_lookup_table_entry *lte,
1163                      struct wim_lookup_table *lookup_table,
1164                      struct wim_lookup_table_entry **lte_ret)
1165 {
1166         int ret;
1167         struct wim_lookup_table_entry *duplicate_lte;
1168         struct wim_lookup_table_entry **back_ptr;
1169
1170         wimlib_assert(lte->unhashed);
1171
1172         /* back_ptr must be saved because @back_inode and @back_stream_id are in
1173          * union with the SHA1 message digest and will no longer be valid once
1174          * the SHA1 has been calculated. */
1175         back_ptr = retrieve_lte_pointer(lte);
1176
1177         ret = sha1_resource(lte);
1178         if (ret)
1179                 return ret;
1180
1181         /* Look for a duplicate stream */
1182         duplicate_lte = __lookup_resource(lookup_table, lte->hash);
1183         list_del(&lte->unhashed_list);
1184         if (duplicate_lte) {
1185                 /* We have a duplicate stream.  Transfer the reference counts
1186                  * from this stream to the duplicate, update the reference to
1187                  * this stream (in an inode or ads_entry) to point to the
1188                  * duplicate, then free this stream. */
1189                 wimlib_assert(!(duplicate_lte->unhashed));
1190                 duplicate_lte->refcnt += lte->refcnt;
1191                 duplicate_lte->out_refcnt += lte->refcnt;
1192                 *back_ptr = duplicate_lte;
1193                 free_lookup_table_entry(lte);
1194                 lte = duplicate_lte;
1195         } else {
1196                 /* No duplicate stream, so we need to insert
1197                  * this stream into the lookup table and treat
1198                  * it as a hashed stream. */
1199                 lookup_table_insert(lookup_table, lte);
1200                 lte->unhashed = 0;
1201         }
1202         if (lte_ret)
1203                 *lte_ret = lte;
1204         return 0;
1205 }