4 * Lookup table, implemented as a hash table, that maps SHA1 message digests to
9 * Copyright (C) 2012, 2013 Eric Biggers
11 * This file is part of wimlib, a library for working with WIM files.
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)
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
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/.
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"
43 # include <unistd.h> /* for unlink() */
46 struct wim_lookup_table *
47 new_lookup_table(size_t capacity)
49 struct wim_lookup_table *table;
50 struct hlist_head *array;
52 table = CALLOC(1, sizeof(struct wim_lookup_table));
54 array = CALLOC(capacity, sizeof(array[0]));
56 table->num_entries = 0;
57 table->capacity = capacity;
62 ERROR("Failed to allocate memory for lookup table "
63 "with capacity %zu", capacity);
69 struct wim_lookup_table_entry *
70 new_lookup_table_entry(void)
72 struct wim_lookup_table_entry *lte;
74 lte = CALLOC(1, sizeof(struct wim_lookup_table_entry));
79 ERROR("Out of memory (tried to allocate %zu bytes for "
80 "lookup table entry)",
81 sizeof(struct wim_lookup_table_entry));
86 struct wim_lookup_table_entry *
87 clone_lookup_table_entry(const struct wim_lookup_table_entry *old)
89 struct wim_lookup_table_entry *new;
91 new = memdup(old, sizeof(struct wim_lookup_table_entry));
95 new->extracted_file = NULL;
96 switch (new->resource_location) {
99 case RESOURCE_WIN32_ENCRYPTED:
101 case RESOURCE_IN_FILE_ON_DISK:
104 case RESOURCE_IN_STAGING_FILE:
105 BUILD_BUG_ON((void*)&old->file_on_disk !=
106 (void*)&old->staging_file_name);
108 new->file_on_disk = TSTRDUP(old->file_on_disk);
109 if (!new->file_on_disk)
112 case RESOURCE_IN_ATTACHED_BUFFER:
113 new->attached_buffer = memdup(old->attached_buffer,
114 wim_resource_size(old));
115 if (!new->attached_buffer)
119 case RESOURCE_IN_NTFS_VOLUME:
121 struct ntfs_location *loc;
122 loc = memdup(old->ntfs_loc, sizeof(struct ntfs_location));
126 loc->stream_name = NULL;
128 loc->path = STRDUP(old->ntfs_loc->path);
131 if (loc->stream_name_nchars) {
132 loc->stream_name = memdup(old->ntfs_loc->stream_name,
133 loc->stream_name_nchars * 2);
134 if (!loc->stream_name)
145 free_lookup_table_entry(new);
150 free_lookup_table_entry(struct wim_lookup_table_entry *lte)
153 switch (lte->resource_location) {
156 case RESOURCE_WIN32_ENCRYPTED:
158 case RESOURCE_IN_FILE_ON_DISK:
161 case RESOURCE_IN_STAGING_FILE:
162 BUILD_BUG_ON((void*)<e->file_on_disk !=
163 (void*)<e->staging_file_name);
165 case RESOURCE_IN_ATTACHED_BUFFER:
166 BUILD_BUG_ON((void*)<e->file_on_disk !=
167 (void*)<e->attached_buffer);
168 FREE(lte->file_on_disk);
171 case RESOURCE_IN_NTFS_VOLUME:
173 FREE(lte->ntfs_loc->path);
174 FREE(lte->ntfs_loc->stream_name);
187 do_free_lookup_table_entry(struct wim_lookup_table_entry *entry, void *ignore)
189 free_lookup_table_entry(entry);
195 free_lookup_table(struct wim_lookup_table *table)
197 DEBUG2("Freeing lookup table");
200 for_lookup_table_entry(table,
201 do_free_lookup_table_entry,
210 * Inserts an entry into the lookup table.
212 * @table: A pointer to the lookup table.
213 * @lte: A pointer to the entry to insert.
216 lookup_table_insert(struct wim_lookup_table *table,
217 struct wim_lookup_table_entry *lte)
219 size_t i = lte->hash_short % table->capacity;
220 hlist_add_head(<e->hash_list, &table->array[i]);
222 /* XXX Make the table grow when too many entries have been inserted. */
223 table->num_entries++;
227 finalize_lte(struct wim_lookup_table_entry *lte)
230 if (lte->resource_location == RESOURCE_IN_STAGING_FILE) {
231 unlink(lte->staging_file_name);
232 list_del(<e->unhashed_list);
235 free_lookup_table_entry(lte);
238 /* Decrements the reference count for the lookup table entry @lte. If its
239 * reference count reaches 0, it is unlinked from the lookup table. If,
240 * furthermore, the entry has no opened file descriptors associated with it, the
243 lte_decrement_refcnt(struct wim_lookup_table_entry *lte,
244 struct wim_lookup_table *table)
246 wimlib_assert(lte != NULL);
247 wimlib_assert(lte->refcnt != 0);
248 if (--lte->refcnt == 0) {
250 list_del(<e->unhashed_list);
252 lookup_table_unlink(table, lte);
254 if (lte->num_opened_fds == 0)
262 lte_decrement_num_opened_fds(struct wim_lookup_table_entry *lte)
264 if (lte->num_opened_fds != 0)
265 if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
270 /* Calls a function on all the entries in the WIM lookup table. Stop early and
271 * return nonzero if any call to the function returns nonzero. */
273 for_lookup_table_entry(struct wim_lookup_table *table,
274 int (*visitor)(struct wim_lookup_table_entry *, void *),
277 struct wim_lookup_table_entry *lte;
278 struct hlist_node *pos, *tmp;
281 for (size_t i = 0; i < table->capacity; i++) {
282 hlist_for_each_entry_safe(lte, pos, tmp, &table->array[i],
285 wimlib_assert2(!(lte->resource_entry.flags & WIM_RESHDR_FLAG_METADATA));
286 ret = visitor(lte, arg);
295 cmp_streams_by_wim_position(const void *p1, const void *p2)
297 const struct wim_lookup_table_entry *lte1, *lte2;
298 lte1 = *(const struct wim_lookup_table_entry**)p1;
299 lte2 = *(const struct wim_lookup_table_entry**)p2;
300 if (lte1->resource_entry.offset < lte2->resource_entry.offset)
302 else if (lte1->resource_entry.offset > lte2->resource_entry.offset)
310 add_lte_to_array(struct wim_lookup_table_entry *lte,
313 struct wim_lookup_table_entry ***pp = _pp;
318 /* Iterate through the lookup table entries, but first sort them by stream
319 * offset in the WIM. Caution: this is intended to be used when the stream
320 * offset field has actually been set. */
322 for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
323 int (*visitor)(struct wim_lookup_table_entry *,
327 struct wim_lookup_table_entry **lte_array, **p;
328 size_t num_streams = table->num_entries;
331 lte_array = MALLOC(num_streams * sizeof(lte_array[0]));
333 return WIMLIB_ERR_NOMEM;
335 for_lookup_table_entry(table, add_lte_to_array, &p);
337 wimlib_assert(p == lte_array + num_streams);
339 qsort(lte_array, num_streams, sizeof(lte_array[0]),
340 cmp_streams_by_wim_position);
342 for (size_t i = 0; i < num_streams; i++) {
343 ret = visitor(lte_array[i], arg);
351 /* On-disk format of a WIM lookup table entry (stream entry). */
352 struct wim_lookup_table_entry_disk {
353 /* Location, offset, compression status, and metadata status of the
355 struct resource_entry_disk resource_entry;
357 /* Which part of the split WIM this stream is in; indexed from 1. */
360 /* Reference count of this stream over all WIM images. */
363 /* SHA1 message digest of the uncompressed data of this stream, or
364 * optionally all zeroes if this stream is of zero length. */
365 u8 hash[SHA1_HASH_SIZE];
369 * Reads the lookup table from a WIM file.
371 * Saves lookup table entries for non-metadata streams in a hash table, and
372 * saves the metadata entry for each image in a special per-image location (the
373 * image_metadata array).
376 read_lookup_table(WIMStruct *w)
380 struct wim_lookup_table *table;
381 struct wim_lookup_table_entry *cur_entry, *duplicate_entry;
382 struct wim_lookup_table_entry_disk
383 table_buf[BUFFER_SIZE / sizeof(struct wim_lookup_table_entry_disk)]
384 _aligned_attribute(8);
386 size_t buf_entries_remaining;
387 const struct wim_lookup_table_entry_disk *disk_entry;
389 DEBUG("Reading lookup table: offset %"PRIu64", size %"PRIu64"",
390 w->hdr.lookup_table_res_entry.offset,
391 w->hdr.lookup_table_res_entry.original_size);
393 if (resource_is_compressed(&w->hdr.lookup_table_res_entry)) {
394 ERROR("Didn't expect a compressed lookup table!");
395 ERROR("Ask the author to implement support for this.");
396 return WIMLIB_ERR_COMPRESSED_LOOKUP_TABLE;
399 num_entries = w->hdr.lookup_table_res_entry.size /
400 sizeof(struct wim_lookup_table_entry_disk);
401 table = new_lookup_table(num_entries * 2 + 1);
403 return WIMLIB_ERR_NOMEM;
405 w->current_image = 0;
406 offset = w->hdr.lookup_table_res_entry.offset;
407 buf_entries_remaining = 0;
408 for (; num_entries != 0;
409 num_entries--, buf_entries_remaining--, disk_entry++)
411 if (buf_entries_remaining == 0) {
412 size_t entries_to_read, bytes_to_read;
414 entries_to_read = min(ARRAY_LEN(table_buf), num_entries);
415 bytes_to_read = entries_to_read * sizeof(struct wim_lookup_table_entry_disk);
416 if (full_pread(w->in_fd, table_buf,
417 bytes_to_read, offset) != bytes_to_read)
419 ERROR_WITH_ERRNO("Error reading lookup table "
420 "(offset=%"PRIu64")", offset);
421 ret = WIMLIB_ERR_READ;
422 goto out_free_lookup_table;
424 offset += bytes_to_read;
425 disk_entry = table_buf;
426 buf_entries_remaining = entries_to_read;
428 cur_entry = new_lookup_table_entry();
430 ret = WIMLIB_ERR_NOMEM;
431 goto out_free_lookup_table;
435 cur_entry->resource_location = RESOURCE_IN_WIM;
436 get_resource_entry(&disk_entry->resource_entry, &cur_entry->resource_entry);
437 cur_entry->part_number = le16_to_cpu(disk_entry->part_number);
438 cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
439 copy_hash(cur_entry->hash, disk_entry->hash);
441 if (cur_entry->part_number != w->hdr.part_number) {
442 ERROR("A lookup table entry in part %hu of the WIM "
443 "points to part %hu",
444 w->hdr.part_number, cur_entry->part_number);
445 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
446 goto out_free_cur_entry;
449 if (is_zero_hash(cur_entry->hash)) {
450 ERROR("The WIM lookup table contains an entry with a "
451 "SHA1 message digest of all 0's");
452 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
453 goto out_free_cur_entry;
456 if (!(cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
457 && (cur_entry->resource_entry.size !=
458 cur_entry->resource_entry.original_size))
460 #ifdef ENABLE_ERROR_MESSAGES
461 ERROR("Found uncompressed resource with original size "
462 "not the same as compressed size");
463 ERROR("The lookup table entry for the resource is as follows:");
464 print_lookup_table_entry(cur_entry, stderr);
466 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
467 goto out_free_cur_entry;
470 if (cur_entry->resource_entry.flags & WIM_RESHDR_FLAG_METADATA) {
471 /* Lookup table entry for a metadata resource */
472 if (cur_entry->refcnt != 1) {
473 #ifdef ENABLE_ERROR_MESSAGES
474 ERROR("Found metadata resource with refcnt != 1:");
475 print_lookup_table_entry(cur_entry, stderr);
477 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
478 goto out_free_cur_entry;
481 if (w->hdr.part_number != 1) {
482 ERROR("Found a metadata resource in a "
483 "non-first part of the split WIM!");
484 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
485 goto out_free_cur_entry;
487 if (w->current_image == w->hdr.image_count) {
488 ERROR("The WIM header says there are %u images "
489 "in the WIM, but we found more metadata "
490 "resources than this", w->hdr.image_count);
491 ret = WIMLIB_ERR_IMAGE_COUNT;
492 goto out_free_cur_entry;
495 /* Notice very carefully: We are assigning the metadata
496 * resources in the exact order mirrored by their lookup
497 * table entries on disk, which is the behavior of
498 * Microsoft's software. In particular, this overrides
499 * the actual locations of the metadata resources
500 * themselves in the WIM file as well as any information
501 * written in the XML data. */
502 DEBUG("Found metadata resource for image %u at "
504 w->current_image + 1,
505 cur_entry->resource_entry.offset);
507 w->current_image++]->metadata_lte = cur_entry;
509 /* Lookup table entry for a stream that is not a
510 * metadata resource */
511 duplicate_entry = __lookup_resource(table, cur_entry->hash);
512 if (duplicate_entry) {
513 #ifdef ENABLE_ERROR_MESSAGES
514 ERROR("The WIM lookup table contains two entries with the "
515 "same SHA1 message digest!");
516 ERROR("The first entry is:");
517 print_lookup_table_entry(duplicate_entry, stderr);
518 ERROR("The second entry is:");
519 print_lookup_table_entry(cur_entry, stderr);
521 ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
522 goto out_free_cur_entry;
524 lookup_table_insert(table, cur_entry);
528 if (w->hdr.part_number == 1 && w->current_image != w->hdr.image_count)
530 ERROR("The WIM header says there are %u images "
531 "in the WIM, but we only found %d metadata "
532 "resources!", w->hdr.image_count, w->current_image);
533 ret = WIMLIB_ERR_IMAGE_COUNT;
534 goto out_free_lookup_table;
536 DEBUG("Done reading lookup table.");
537 w->lookup_table = table;
542 out_free_lookup_table:
543 free_lookup_table(table);
545 w->current_image = 0;
551 write_lookup_table_entry(const struct wim_lookup_table_entry *lte,
552 struct wim_lookup_table_entry_disk *disk_entry)
554 put_resource_entry(<e->output_resource_entry, &disk_entry->resource_entry);
555 disk_entry->part_number = cpu_to_le16(lte->part_number);
556 disk_entry->refcnt = cpu_to_le32(lte->out_refcnt);
557 copy_hash(disk_entry->hash, lte->hash);
561 write_lookup_table_from_stream_list(struct list_head *stream_list,
563 struct resource_entry *out_res_entry)
567 struct wim_lookup_table_entry_disk
568 table_buf[BUFFER_SIZE / sizeof(struct wim_lookup_table_entry_disk)]
569 _aligned_attribute(8);
571 size_t bytes_to_write;
572 struct wim_lookup_table_entry *lte;
575 start_offset = filedes_offset(out_fd);
576 if (start_offset == -1)
581 list_for_each_entry(lte, stream_list, lookup_table_list) {
582 if (cur_idx == ARRAY_LEN(table_buf)) {
583 bytes_to_write = sizeof(table_buf);
584 if (full_write(out_fd, table_buf,
585 bytes_to_write) != bytes_to_write)
587 table_size += bytes_to_write;
590 write_lookup_table_entry(lte, &table_buf[cur_idx]);
594 bytes_to_write = cur_idx * sizeof(struct wim_lookup_table_entry_disk);
595 if (full_write(out_fd, table_buf,
596 bytes_to_write) != bytes_to_write)
598 table_size += bytes_to_write;
600 out_res_entry->offset = start_offset;
601 out_res_entry->size = table_size;
602 out_res_entry->original_size = table_size;
603 out_res_entry->flags = WIM_RESHDR_FLAG_METADATA;
608 ERROR_WITH_ERRNO("Failed to write lookup table");
609 ret = WIMLIB_ERR_WRITE;
614 append_lookup_table_entry(struct wim_lookup_table_entry *lte, void *_list)
616 if (lte->out_refcnt != 0)
617 list_add_tail(<e->lookup_table_list, (struct list_head*)_list);
621 /* Writes the WIM lookup table to the output file. */
623 write_lookup_table(WIMStruct *w, int image, struct resource_entry *out_res_entry)
625 LIST_HEAD(stream_list);
629 if (image == WIMLIB_ALL_IMAGES) {
631 end_image = w->hdr.image_count;
637 for (int i = start_image; i <= end_image; i++) {
638 struct wim_lookup_table_entry *metadata_lte;
640 metadata_lte = w->image_metadata[i - 1]->metadata_lte;
641 metadata_lte->out_refcnt = 1;
642 metadata_lte->output_resource_entry.flags |= WIM_RESHDR_FLAG_METADATA;
643 append_lookup_table_entry(metadata_lte, &stream_list);
645 for_lookup_table_entry(w->lookup_table,
646 append_lookup_table_entry,
648 return write_lookup_table_from_stream_list(&stream_list,
654 lte_zero_real_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
656 lte->real_refcnt = 0;
661 lte_zero_out_refcnt(struct wim_lookup_table_entry *lte, void *_ignore)
668 lte_free_extracted_file(struct wim_lookup_table_entry *lte, void *_ignore)
670 if (lte->extracted_file != NULL) {
671 FREE(lte->extracted_file);
672 lte->extracted_file = NULL;
678 print_lookup_table_entry(const struct wim_lookup_table_entry *lte, FILE *out)
684 tfprintf(out, T("Offset = %"PRIu64" bytes\n"),
685 lte->resource_entry.offset);
687 tfprintf(out, T("Size = %"PRIu64" bytes\n"),
688 (u64)lte->resource_entry.size);
690 tfprintf(out, T("Original size = %"PRIu64" bytes\n"),
691 lte->resource_entry.original_size);
693 tfprintf(out, T("Part Number = %hu\n"), lte->part_number);
694 tfprintf(out, T("Reference Count = %u\n"), lte->refcnt);
697 tfprintf(out, T("(Unhashed: inode %p, stream_id = %u)\n"),
698 lte->back_inode, lte->back_stream_id);
700 tfprintf(out, T("Hash = 0x"));
701 print_hash(lte->hash, out);
705 tfprintf(out, T("Flags = "));
706 u8 flags = lte->resource_entry.flags;
707 if (flags & WIM_RESHDR_FLAG_COMPRESSED)
708 tfputs(T("WIM_RESHDR_FLAG_COMPRESSED, "), out);
709 if (flags & WIM_RESHDR_FLAG_FREE)
710 tfputs(T("WIM_RESHDR_FLAG_FREE, "), out);
711 if (flags & WIM_RESHDR_FLAG_METADATA)
712 tfputs(T("WIM_RESHDR_FLAG_METADATA, "), out);
713 if (flags & WIM_RESHDR_FLAG_SPANNED)
714 tfputs(T("WIM_RESHDR_FLAG_SPANNED, "), out);
716 switch (lte->resource_location) {
717 case RESOURCE_IN_WIM:
718 if (lte->wim->filename) {
719 tfprintf(out, T("WIM file = `%"TS"'\n"),
725 case RESOURCE_WIN32_ENCRYPTED:
727 case RESOURCE_IN_FILE_ON_DISK:
729 tfprintf(out, T("File on Disk = `%"TS"'\n"),
733 case RESOURCE_IN_STAGING_FILE:
734 tfprintf(out, T("Staging File = `%"TS"'\n"),
735 lte->staging_file_name);
745 do_print_lookup_table_entry(struct wim_lookup_table_entry *lte, void *fp)
747 print_lookup_table_entry(lte, (FILE*)fp);
752 * Prints the lookup table of a WIM file.
755 wimlib_print_lookup_table(WIMStruct *w)
757 for_lookup_table_entry(w->lookup_table,
758 do_print_lookup_table_entry,
762 /* Given a SHA1 message digest, return the corresponding entry in the WIM's
763 * lookup table, or NULL if there is none. */
764 struct wim_lookup_table_entry *
765 __lookup_resource(const struct wim_lookup_table *table, const u8 hash[])
768 struct wim_lookup_table_entry *lte;
769 struct hlist_node *pos;
771 wimlib_assert(table != NULL);
772 wimlib_assert(hash != NULL);
774 i = *(size_t*)hash % table->capacity;
775 hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
776 if (hashes_equal(hash, lte->hash))
783 * Finds the dentry, lookup table entry, and stream index for a WIM file stream,
786 * This is only for pre-resolved inodes.
789 lookup_resource(WIMStruct *w,
792 struct wim_dentry **dentry_ret,
793 struct wim_lookup_table_entry **lte_ret,
796 struct wim_dentry *dentry;
797 struct wim_lookup_table_entry *lte;
799 const tchar *stream_name = NULL;
800 struct wim_inode *inode;
803 if (lookup_flags & LOOKUP_FLAG_ADS_OK) {
804 stream_name = path_stream_name(path);
806 p = (tchar*)stream_name - 1;
811 dentry = get_dentry(w, path);
817 inode = dentry->d_inode;
819 wimlib_assert(inode->i_resolved);
821 if (!(lookup_flags & LOOKUP_FLAG_DIRECTORY_OK)
822 && inode_is_directory(inode))
826 struct wim_ads_entry *ads_entry;
828 ads_entry = inode_get_ads_entry(inode, stream_name,
831 stream_idx = ads_idx + 1;
832 lte = ads_entry->lte;
843 *dentry_ret = dentry;
847 *stream_idx_ret = stream_idx;
853 * XXX Probably should store the compression type directly in the lookup table
857 wim_resource_compression_type(const struct wim_lookup_table_entry *lte)
859 if (!(lte->resource_entry.flags & WIM_RESHDR_FLAG_COMPRESSED)
860 || lte->resource_location != RESOURCE_IN_WIM)
861 return WIMLIB_COMPRESSION_TYPE_NONE;
862 return wimlib_get_compression_type(lte->wim);
865 /* Resolve an inode's lookup table entries
867 * This replaces the SHA1 hash fields (which are used to lookup an entry in the
868 * lookup table) with pointers directly to the lookup table entries. A circular
869 * linked list of streams sharing the same lookup table entry is created.
871 * This function always succeeds; unresolved lookup table entries are given a
875 inode_resolve_ltes(struct wim_inode *inode, struct wim_lookup_table *table)
878 if (!inode->i_resolved) {
879 struct wim_lookup_table_entry *lte;
880 /* Resolve the default file stream */
881 lte = __lookup_resource(table, inode->i_hash);
883 inode->i_resolved = 1;
885 /* Resolve the alternate data streams */
886 for (u16 i = 0; i < inode->i_num_ads; i++) {
887 struct wim_ads_entry *cur_entry = &inode->i_ads_entries[i];
888 lte = __lookup_resource(table, cur_entry->hash);
889 cur_entry->lte = lte;
895 inode_unresolve_ltes(struct wim_inode *inode)
897 if (inode->i_resolved) {
899 copy_hash(inode->i_hash, inode->i_lte->hash);
901 zero_out_hash(inode->i_hash);
903 for (u16 i = 0; i < inode->i_num_ads; i++) {
904 if (inode->i_ads_entries[i].lte)
905 copy_hash(inode->i_ads_entries[i].hash,
906 inode->i_ads_entries[i].lte->hash);
908 zero_out_hash(inode->i_ads_entries[i].hash);
910 inode->i_resolved = 0;
915 * Returns the lookup table entry for stream @stream_idx of the inode, where
916 * stream_idx = 0 means the default un-named file stream, and stream_idx >= 1
917 * corresponds to an alternate data stream.
919 * This works for both resolved and un-resolved inodes.
921 struct wim_lookup_table_entry *
922 inode_stream_lte(const struct wim_inode *inode, unsigned stream_idx,
923 const struct wim_lookup_table *table)
925 if (inode->i_resolved)
926 return inode_stream_lte_resolved(inode, stream_idx);
928 return inode_stream_lte_unresolved(inode, stream_idx, table);
931 struct wim_lookup_table_entry *
932 inode_unnamed_lte_resolved(const struct wim_inode *inode)
934 wimlib_assert(inode->i_resolved);
935 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
936 if (inode_stream_name_nbytes(inode, i) == 0 &&
937 !is_zero_hash(inode_stream_hash_resolved(inode, i)))
939 return inode_stream_lte_resolved(inode, i);
945 struct wim_lookup_table_entry *
946 inode_unnamed_lte_unresolved(const struct wim_inode *inode,
947 const struct wim_lookup_table *table)
949 wimlib_assert(!inode->i_resolved);
950 for (unsigned i = 0; i <= inode->i_num_ads; i++) {
951 if (inode_stream_name_nbytes(inode, i) == 0 &&
952 !is_zero_hash(inode_stream_hash_unresolved(inode, i)))
954 return inode_stream_lte_unresolved(inode, i, table);
960 /* Return the lookup table entry for the unnamed data stream of an inode, or
961 * NULL if there is none.
963 * You'd think this would be easier than it actually is, since the unnamed data
964 * stream should be the one referenced from the inode itself. Alas, if there
965 * are named data streams, Microsoft's "imagex.exe" program will put the unnamed
966 * data stream in one of the alternate data streams instead of inside the WIM
967 * dentry itself. So we need to check the alternate data streams too.
969 * Also, note that a dentry may appear to have more than one unnamed stream, but
970 * if the SHA1 message digest is all 0's then the corresponding stream does not
971 * really "count" (this is the case for the inode's own file stream when the
972 * file stream that should be there is actually in one of the alternate stream
973 * entries.). This is despite the fact that we may need to extract such a
974 * missing entry as an empty file or empty named data stream.
976 struct wim_lookup_table_entry *
977 inode_unnamed_lte(const struct wim_inode *inode,
978 const struct wim_lookup_table *table)
980 if (inode->i_resolved)
981 return inode_unnamed_lte_resolved(inode);
983 return inode_unnamed_lte_unresolved(inode, table);
987 lte_add_stream_size(struct wim_lookup_table_entry *lte, void *total_bytes_p)
989 *(u64*)total_bytes_p += lte->resource_entry.size;
994 lookup_table_total_stream_size(struct wim_lookup_table *table)
997 for_lookup_table_entry(table, lte_add_stream_size, &total_size);
1001 struct wim_lookup_table_entry **
1002 retrieve_lte_pointer(struct wim_lookup_table_entry *lte)
1004 wimlib_assert(lte->unhashed);
1005 struct wim_inode *inode = lte->back_inode;
1006 u32 stream_id = lte->back_stream_id;
1008 return &inode->i_lte;
1010 for (u16 i = 0; i < inode->i_num_ads; i++)
1011 if (inode->i_ads_entries[i].stream_id == stream_id)
1012 return &inode->i_ads_entries[i].lte;
1017 /* Calculate the SHA1 message digest of a stream and move it from the list of
1018 * unhashed streams to the stream lookup table, possibly joining it with an
1019 * existing lookup table entry for an identical stream.
1021 * @lte: An unhashed lookup table entry.
1022 * @lookup_table: Lookup table for the WIM.
1023 * @lte_ret: On success, write a pointer to the resulting lookup table
1024 * entry to this location. This will be the same as @lte
1025 * if it was inserted into the lookup table, or different if
1026 * a duplicate stream was found.
1028 * Returns 0 on success; nonzero if there is an error reading the stream.
1031 hash_unhashed_stream(struct wim_lookup_table_entry *lte,
1032 struct wim_lookup_table *lookup_table,
1033 struct wim_lookup_table_entry **lte_ret)
1036 struct wim_lookup_table_entry *duplicate_lte;
1037 struct wim_lookup_table_entry **back_ptr;
1039 wimlib_assert(lte->unhashed);
1041 /* back_ptr must be saved because @back_inode and @back_stream_id are in
1042 * union with the SHA1 message digest and will no longer be valid once
1043 * the SHA1 has been calculated. */
1044 back_ptr = retrieve_lte_pointer(lte);
1046 ret = sha1_resource(lte);
1050 /* Look for a duplicate stream */
1051 duplicate_lte = __lookup_resource(lookup_table, lte->hash);
1052 list_del(<e->unhashed_list);
1053 if (duplicate_lte) {
1054 /* We have a duplicate stream. Transfer the reference counts
1055 * from this stream to the duplicate, update the reference to
1056 * this stream (in an inode or ads_entry) to point to the
1057 * duplicate, then free this stream. */
1058 wimlib_assert(!(duplicate_lte->unhashed));
1059 duplicate_lte->refcnt += lte->refcnt;
1060 duplicate_lte->out_refcnt += lte->refcnt;
1061 *back_ptr = duplicate_lte;
1062 free_lookup_table_entry(lte);
1063 lte = duplicate_lte;
1065 /* No duplicate stream, so we need to insert
1066 * this stream into the lookup table and treat
1067 * it as a hashed stream. */
1068 lookup_table_insert(lookup_table, lte);