-/*
- * lookup_table.c
- *
- * Lookup table, implemented as a hash table, that maps SHA1 message digests to
- * data streams; plus code to read and write the corresponding on-disk data.
- */
-
-/*
- * Copyright (C) 2012, 2013, 2014 Eric Biggers
- *
- * This file is free software; you can redistribute it and/or modify it under
- * the terms of the GNU Lesser General Public License as published by the Free
- * Software Foundation; either version 3 of the License, or (at your option) any
- * later version.
- *
- * This file is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
- * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
- * details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this file; if not, see http://www.gnu.org/licenses/.
- */
-
-#ifdef HAVE_CONFIG_H
-# include "config.h"
-#endif
-
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h> /* for unlink() */
-
-#include "wimlib/assert.h"
-#include "wimlib/endianness.h"
-#include "wimlib/error.h"
-#include "wimlib/lookup_table.h"
-#include "wimlib/metadata.h"
-#include "wimlib/ntfs_3g.h"
-#include "wimlib/resource.h"
-#include "wimlib/unaligned.h"
-#include "wimlib/util.h"
-#include "wimlib/write.h"
-
-/* WIM lookup table:
- *
- * This is a logical mapping from SHA1 message digests to the data streams
- * contained in a WIM.
- *
- * Here it is implemented as a hash table.
- *
- * Note: Everything will break horribly if there is a SHA1 collision.
- */
-struct wim_lookup_table {
- struct hlist_head *array;
- size_t num_entries;
- size_t capacity;
-};
-
-struct wim_lookup_table *
-new_lookup_table(size_t capacity)
-{
- struct wim_lookup_table *table;
- struct hlist_head *array;
-
- table = MALLOC(sizeof(struct wim_lookup_table));
- if (table == NULL)
- goto oom;
-
- array = CALLOC(capacity, sizeof(array[0]));
- if (array == NULL) {
- FREE(table);
- goto oom;
- }
-
- table->num_entries = 0;
- table->capacity = capacity;
- table->array = array;
- return table;
-
-oom:
- ERROR("Failed to allocate memory for lookup table "
- "with capacity %zu", capacity);
- return NULL;
-}
-
-static int
-do_free_lookup_table_entry(struct wim_lookup_table_entry *entry, void *ignore)
-{
- free_lookup_table_entry(entry);
- return 0;
-}
-
-void
-free_lookup_table(struct wim_lookup_table *table)
-{
- if (table) {
- for_lookup_table_entry(table, do_free_lookup_table_entry, NULL);
- FREE(table->array);
- FREE(table);
- }
-}
-
-struct wim_lookup_table_entry *
-new_lookup_table_entry(void)
-{
- struct wim_lookup_table_entry *lte;
-
- lte = CALLOC(1, sizeof(struct wim_lookup_table_entry));
- if (lte == NULL)
- return NULL;
-
- lte->refcnt = 1;
-
- /* lte->resource_location = RESOURCE_NONEXISTENT */
- BUILD_BUG_ON(RESOURCE_NONEXISTENT != 0);
-
- return lte;
-}
-
-struct wim_lookup_table_entry *
-clone_lookup_table_entry(const struct wim_lookup_table_entry *old)
-{
- struct wim_lookup_table_entry *new;
-
- new = memdup(old, sizeof(struct wim_lookup_table_entry));
- if (new == NULL)
- return NULL;
-
- switch (new->resource_location) {
- case RESOURCE_IN_WIM:
- list_add(&new->rspec_node, &new->rspec->stream_list);
- break;
-
- case RESOURCE_IN_FILE_ON_DISK:
-#ifdef __WIN32__
- case RESOURCE_IN_WINNT_FILE_ON_DISK:
- case RESOURCE_WIN32_ENCRYPTED:
-#endif
-#ifdef WITH_FUSE
- case RESOURCE_IN_STAGING_FILE:
- BUILD_BUG_ON((void*)&old->file_on_disk !=
- (void*)&old->staging_file_name);
-#endif
- new->file_on_disk = TSTRDUP(old->file_on_disk);
- if (new->file_on_disk == NULL)
- goto out_free;
- break;
- case RESOURCE_IN_ATTACHED_BUFFER:
- new->attached_buffer = memdup(old->attached_buffer, old->size);
- if (new->attached_buffer == NULL)
- goto out_free;
- break;
-#ifdef WITH_NTFS_3G
- case RESOURCE_IN_NTFS_VOLUME:
- if (old->ntfs_loc) {
- struct ntfs_location *loc;
- loc = memdup(old->ntfs_loc, sizeof(struct ntfs_location));
- if (loc == NULL)
- goto out_free;
- loc->path = NULL;
- loc->stream_name = NULL;
- new->ntfs_loc = loc;
- loc->path = STRDUP(old->ntfs_loc->path);
- if (loc->path == NULL)
- goto out_free;
- if (loc->stream_name_nchars != 0) {
- loc->stream_name = memdup(old->ntfs_loc->stream_name,
- loc->stream_name_nchars * 2);
- if (loc->stream_name == NULL)
- goto out_free;
- }
- }
- break;
-#endif
- default:
- break;
- }
- return new;
-
-out_free:
- free_lookup_table_entry(new);
- return NULL;
-}
-
-void
-lte_put_resource(struct wim_lookup_table_entry *lte)
-{
- switch (lte->resource_location) {
- case RESOURCE_IN_WIM:
- list_del(<e->rspec_node);
- if (list_empty(<e->rspec->stream_list))
- FREE(lte->rspec);
- break;
- case RESOURCE_IN_FILE_ON_DISK:
-#ifdef __WIN32__
- case RESOURCE_IN_WINNT_FILE_ON_DISK:
- case RESOURCE_WIN32_ENCRYPTED:
-#endif
-#ifdef WITH_FUSE
- case RESOURCE_IN_STAGING_FILE:
- BUILD_BUG_ON((void*)<e->file_on_disk !=
- (void*)<e->staging_file_name);
-#endif
- case RESOURCE_IN_ATTACHED_BUFFER:
- BUILD_BUG_ON((void*)<e->file_on_disk !=
- (void*)<e->attached_buffer);
- FREE(lte->file_on_disk);
- break;
-#ifdef WITH_NTFS_3G
- case RESOURCE_IN_NTFS_VOLUME:
- if (lte->ntfs_loc) {
- FREE(lte->ntfs_loc->path);
- FREE(lte->ntfs_loc->stream_name);
- FREE(lte->ntfs_loc);
- }
- break;
-#endif
- default:
- break;
- }
-}
-
-void
-free_lookup_table_entry(struct wim_lookup_table_entry *lte)
-{
- if (lte) {
- lte_put_resource(lte);
- FREE(lte);
- }
-}
-
-/* Should this stream be retained even if it has no references? */
-static bool
-should_retain_lte(const struct wim_lookup_table_entry *lte)
-{
- return lte->resource_location == RESOURCE_IN_WIM;
-}
-
-static void
-finalize_lte(struct wim_lookup_table_entry *lte)
-{
- if (!should_retain_lte(lte))
- free_lookup_table_entry(lte);
-}
-
-/*
- * Decrements the reference count of the single-instance stream @lte, which must
- * be inserted in the stream lookup table @table.
- *
- * If the stream's reference count reaches 0, we may unlink it from @table and
- * free it. However, we retain streams with 0 reference count that originated
- * from WIM files (RESOURCE_IN_WIM). We do this for two reasons:
- *
- * 1. This prevents information about valid streams in a WIM file --- streams
- * which will continue to be present after appending to the WIM file --- from
- * being lost merely because we dropped all references to them.
- *
- * 2. Stream reference counts we read from WIM files can't be trusted. It's
- * possible that a WIM has reference counts that are too low; WIMGAPI
- * sometimes creates WIMs where this is the case. It's also possible that
- * streams have been referenced from an external WIM; those streams can
- * potentially have any reference count at all, either lower or higher than
- * would be expected for this WIM ("this WIM" meaning the owner of @table) if
- * it were a standalone WIM.
- *
- * So we can't take the reference counts too seriously. But at least, we do
- * recalculate by default when writing a new WIM file.
- */
-void
-lte_decrement_refcnt(struct wim_lookup_table_entry *lte,
- struct wim_lookup_table *table)
-{
- if (unlikely(lte->refcnt == 0)) /* See comment above */
- return;
-
- if (--lte->refcnt == 0) {
- if (lte->unhashed) {
- list_del(<e->unhashed_list);
- #ifdef WITH_FUSE
- /* If the stream has been extracted to a staging file
- * for a FUSE mount, unlink the staging file. (Note
- * that there still may be open file descriptors to it.)
- * */
- if (lte->resource_location == RESOURCE_IN_STAGING_FILE)
- unlinkat(lte->staging_dir_fd,
- lte->staging_file_name, 0);
- #endif
- } else {
- if (!should_retain_lte(lte))
- lookup_table_unlink(table, lte);
- }
-
- /* If FUSE mounts are enabled, we don't actually free the entry
- * until the last file descriptor has been closed by
- * lte_decrement_num_opened_fds(). */
-#ifdef WITH_FUSE
- if (lte->num_opened_fds == 0)
-#endif
- finalize_lte(lte);
- }
-}
-
-#ifdef WITH_FUSE
-void
-lte_decrement_num_opened_fds(struct wim_lookup_table_entry *lte)
-{
- wimlib_assert(lte->num_opened_fds != 0);
-
- if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
- finalize_lte(lte);
-}
-#endif
-
-static void
-lookup_table_insert_raw(struct wim_lookup_table *table,
- struct wim_lookup_table_entry *lte)
-{
- size_t i = lte->hash_short % table->capacity;
-
- hlist_add_head(<e->hash_list, &table->array[i]);
-}
-
-static void
-enlarge_lookup_table(struct wim_lookup_table *table)
-{
- size_t old_capacity, new_capacity;
- struct hlist_head *old_array, *new_array;
- struct wim_lookup_table_entry *lte;
- struct hlist_node *cur, *tmp;
- size_t i;
-
- old_capacity = table->capacity;
- new_capacity = old_capacity * 2;
- new_array = CALLOC(new_capacity, sizeof(struct hlist_head));
- if (new_array == NULL)
- return;
- old_array = table->array;
- table->array = new_array;
- table->capacity = new_capacity;
-
- for (i = 0; i < old_capacity; i++) {
- hlist_for_each_entry_safe(lte, cur, tmp, &old_array[i], hash_list) {
- hlist_del(<e->hash_list);
- lookup_table_insert_raw(table, lte);
- }
- }
- FREE(old_array);
-}
-
-/* Inserts an entry into the lookup table. */
-void
-lookup_table_insert(struct wim_lookup_table *table,
- struct wim_lookup_table_entry *lte)
-{
- lookup_table_insert_raw(table, lte);
- if (++table->num_entries > table->capacity)
- enlarge_lookup_table(table);
-}
-
-/* Unlinks a lookup table entry from the table; does not free it. */
-void
-lookup_table_unlink(struct wim_lookup_table *table,
- struct wim_lookup_table_entry *lte)
-{
- wimlib_assert(!lte->unhashed);
- wimlib_assert(table->num_entries != 0);
-
- hlist_del(<e->hash_list);
- table->num_entries--;
-}
-
-/* Given a SHA1 message digest, return the corresponding entry in the WIM's
- * lookup table, or NULL if there is none. */
-struct wim_lookup_table_entry *
-lookup_stream(const struct wim_lookup_table *table, const u8 hash[])
-{
- size_t i;
- struct wim_lookup_table_entry *lte;
- struct hlist_node *pos;
-
- i = load_size_t_unaligned(hash) % table->capacity;
- hlist_for_each_entry(lte, pos, &table->array[i], hash_list)
- if (hashes_equal(hash, lte->hash))
- return lte;
- return NULL;
-}
-
-/* Calls a function on all the entries in the WIM lookup table. Stop early and
- * return nonzero if any call to the function returns nonzero. */
-int
-for_lookup_table_entry(struct wim_lookup_table *table,
- int (*visitor)(struct wim_lookup_table_entry *, void *),
- void *arg)
-{
- struct wim_lookup_table_entry *lte;
- struct hlist_node *pos, *tmp;
- int ret;
-
- for (size_t i = 0; i < table->capacity; i++) {
- hlist_for_each_entry_safe(lte, pos, tmp, &table->array[i],
- hash_list)
- {
- ret = visitor(lte, arg);
- if (ret)
- return ret;
- }
- }
- return 0;
-}
-
-/* qsort() callback that sorts streams (represented by `struct
- * wim_lookup_table_entry's) into an order optimized for reading.
- *
- * Sorting is done primarily by resource location, then secondarily by a
- * per-resource location order. For example, resources in WIM files are sorted
- * primarily by part number, then secondarily by offset, as to implement optimal
- * reading of either a standalone or split WIM. */
-int
-cmp_streams_by_sequential_order(const void *p1, const void *p2)
-{
- const struct wim_lookup_table_entry *lte1, *lte2;
- int v;
- WIMStruct *wim1, *wim2;
-
- lte1 = *(const struct wim_lookup_table_entry**)p1;
- lte2 = *(const struct wim_lookup_table_entry**)p2;
-
- v = (int)lte1->resource_location - (int)lte2->resource_location;
-
- /* Different resource locations? */
- if (v)
- return v;
-
- switch (lte1->resource_location) {
- case RESOURCE_IN_WIM:
- wim1 = lte1->rspec->wim;
- wim2 = lte2->rspec->wim;
-
- /* Different (possibly split) WIMs? */
- if (wim1 != wim2) {
- v = memcmp(wim1->hdr.guid, wim2->hdr.guid, WIM_GUID_LEN);
- if (v)
- return v;
- }
-
- /* Different part numbers in the same WIM? */
- v = (int)wim1->hdr.part_number - (int)wim2->hdr.part_number;
- if (v)
- return v;
-
- if (lte1->rspec->offset_in_wim != lte2->rspec->offset_in_wim)
- return cmp_u64(lte1->rspec->offset_in_wim,
- lte2->rspec->offset_in_wim);
-
- return cmp_u64(lte1->offset_in_res, lte2->offset_in_res);
-
- case RESOURCE_IN_FILE_ON_DISK:
-#ifdef WITH_FUSE
- case RESOURCE_IN_STAGING_FILE:
-#endif
-#ifdef __WIN32__
- case RESOURCE_IN_WINNT_FILE_ON_DISK:
- case RESOURCE_WIN32_ENCRYPTED:
-#endif
- /* Compare files by path: just a heuristic that will place files
- * in the same directory next to each other. */
- return tstrcmp(lte1->file_on_disk, lte2->file_on_disk);
-#ifdef WITH_NTFS_3G
- case RESOURCE_IN_NTFS_VOLUME:
- return tstrcmp(lte1->ntfs_loc->path, lte2->ntfs_loc->path);
-#endif
- default:
- /* No additional sorting order defined for this resource
- * location (e.g. RESOURCE_IN_ATTACHED_BUFFER); simply compare
- * everything equal to each other. */
- return 0;
- }
-}
-
-int
-sort_stream_list(struct list_head *stream_list,
- size_t list_head_offset,
- int (*compar)(const void *, const void*))
-{
- struct list_head *cur;
- struct wim_lookup_table_entry **array;
- size_t i;
- size_t array_size;
- size_t num_streams = 0;
-
- list_for_each(cur, stream_list)
- num_streams++;
-
- if (num_streams <= 1)
- return 0;
-
- array_size = num_streams * sizeof(array[0]);
- array = MALLOC(array_size);
- if (array == NULL)
- return WIMLIB_ERR_NOMEM;
-
- cur = stream_list->next;
- for (i = 0; i < num_streams; i++) {
- array[i] = (struct wim_lookup_table_entry*)((u8*)cur -
- list_head_offset);
- cur = cur->next;
- }
-
- qsort(array, num_streams, sizeof(array[0]), compar);
-
- INIT_LIST_HEAD(stream_list);
- for (i = 0; i < num_streams; i++) {
- list_add_tail((struct list_head*)
- ((u8*)array[i] + list_head_offset),
- stream_list);
- }
- FREE(array);
- return 0;
-}
-
-/* Sort the specified list of streams in an order optimized for reading. */
-int
-sort_stream_list_by_sequential_order(struct list_head *stream_list,
- size_t list_head_offset)
-{
- return sort_stream_list(stream_list, list_head_offset,
- cmp_streams_by_sequential_order);
-}
-
-
-static int
-add_lte_to_array(struct wim_lookup_table_entry *lte,
- void *_pp)
-{
- struct wim_lookup_table_entry ***pp = _pp;
- *(*pp)++ = lte;
- return 0;
-}
-
-/* Iterate through the lookup table entries, but first sort them by stream
- * offset in the WIM. Caution: this is intended to be used when the stream
- * offset field has actually been set. */
-int
-for_lookup_table_entry_pos_sorted(struct wim_lookup_table *table,
- int (*visitor)(struct wim_lookup_table_entry *,
- void *),
- void *arg)
-{
- struct wim_lookup_table_entry **lte_array, **p;
- size_t num_streams = table->num_entries;
- int ret;
-
- lte_array = MALLOC(num_streams * sizeof(lte_array[0]));
- if (!lte_array)
- return WIMLIB_ERR_NOMEM;
- p = lte_array;
- for_lookup_table_entry(table, add_lte_to_array, &p);
-
- wimlib_assert(p == lte_array + num_streams);
-
- qsort(lte_array, num_streams, sizeof(lte_array[0]),
- cmp_streams_by_sequential_order);
- ret = 0;
- for (size_t i = 0; i < num_streams; i++) {
- ret = visitor(lte_array[i], arg);
- if (ret)
- break;
- }
- FREE(lte_array);
- return ret;
-}
-
-/* On-disk format of a WIM lookup table entry (stream entry). */
-struct wim_lookup_table_entry_disk {
- /* Size, offset, and flags of the stream. */
- struct wim_reshdr_disk reshdr;
-
- /* Which part of the split WIM this stream is in; indexed from 1. */
- le16 part_number;
-
- /* Reference count of this stream over all WIM images. (But see comment
- * above lte_decrement_refcnt().) */
- le32 refcnt;
-
- /* SHA1 message digest of the uncompressed data of this stream, or
- * optionally all zeroes if this stream is of zero length. */
- u8 hash[SHA1_HASH_SIZE];
-} _packed_attribute;
-
-#define WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE 50
-
-/* Given a nonempty run of consecutive lookup table entries with the SOLID flag
- * set, count how many specify resources (as opposed to streams within those
- * resources).
- *
- * Returns the resulting count. */
-static size_t
-count_solid_resources(const struct wim_lookup_table_entry_disk *entries, size_t max)
-{
- size_t count = 0;
- do {
- struct wim_reshdr reshdr;
-
- get_wim_reshdr(&(entries++)->reshdr, &reshdr);
-
- if (!(reshdr.flags & WIM_RESHDR_FLAG_SOLID)) {
- /* Run was terminated by a stand-alone stream entry. */
- break;
- }
-
- if (reshdr.uncompressed_size == SOLID_RESOURCE_MAGIC_NUMBER) {
- /* This is a resource entry. */
- count++;
- }
- } while (--max);
- return count;
-}
-
-/*
- * Given a run of consecutive lookup table entries with the SOLID flag set and
- * having @num_rspecs resource entries, load resource information from them into
- * the resource specifications in the @rspecs array.
- *
- * Returns 0 on success, or a nonzero error code on failure.
- */
-static int
-do_load_solid_info(WIMStruct *wim, struct wim_resource_spec **rspecs,
- size_t num_rspecs,
- const struct wim_lookup_table_entry_disk *entries)
-{
- for (size_t i = 0; i < num_rspecs; i++) {
- struct wim_reshdr reshdr;
- struct alt_chunk_table_header_disk hdr;
- struct wim_resource_spec *rspec;
- int ret;
-
- /* Advance to next resource entry. */
-
- do {
- get_wim_reshdr(&(entries++)->reshdr, &reshdr);
- } while (reshdr.uncompressed_size != SOLID_RESOURCE_MAGIC_NUMBER);
-
- rspec = rspecs[i];
-
- wim_res_hdr_to_spec(&reshdr, wim, rspec);
-
- /* For solid resources, the uncompressed size, compression type,
- * and chunk size are stored in the resource itself, not in the
- * lookup table. */
-
- ret = full_pread(&wim->in_fd, &hdr,
- sizeof(hdr), reshdr.offset_in_wim);
- if (ret) {
- ERROR("Failed to read header of solid resource "
- "(offset_in_wim=%"PRIu64")",
- reshdr.offset_in_wim);
- return ret;
- }
-
- rspec->uncompressed_size = le64_to_cpu(hdr.res_usize);
-
- /* Compression format numbers must be the same as in
- * WIMGAPI to be compatible here. */
- BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_NONE != 0);
- BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_XPRESS != 1);
- BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_LZX != 2);
- BUILD_BUG_ON(WIMLIB_COMPRESSION_TYPE_LZMS != 3);
- rspec->compression_type = le32_to_cpu(hdr.compression_format);
-
- rspec->chunk_size = le32_to_cpu(hdr.chunk_size);
-
- DEBUG("Solid resource %zu/%zu: %"PRIu64" => %"PRIu64" "
- "(%"TS"/%"PRIu32") @ +%"PRIu64"",
- i + 1, num_rspecs,
- rspec->uncompressed_size,
- rspec->size_in_wim,
- wimlib_get_compression_type_string(rspec->compression_type),
- rspec->chunk_size,
- rspec->offset_in_wim);
-
- }
- return 0;
-}
-
-/*
- * Given a nonempty run of consecutive lookup table entries with the SOLID flag
- * set, allocate a 'struct wim_resource_spec' for each resource within that run.
- *
- * Returns 0 on success, or a nonzero error code on failure.
- * Returns the pointers and count in *rspecs_ret and *num_rspecs_ret.
- */
-static int
-load_solid_info(WIMStruct *wim,
- const struct wim_lookup_table_entry_disk *entries,
- size_t num_remaining_entries,
- struct wim_resource_spec ***rspecs_ret,
- size_t *num_rspecs_ret)
-{
- size_t num_rspecs;
- struct wim_resource_spec **rspecs;
- size_t i;
- int ret;
-
- num_rspecs = count_solid_resources(entries, num_remaining_entries);
- rspecs = CALLOC(num_rspecs, sizeof(rspecs[0]));
- if (!rspecs)
- return WIMLIB_ERR_NOMEM;
-
- for (i = 0; i < num_rspecs; i++) {
- rspecs[i] = MALLOC(sizeof(struct wim_resource_spec));
- if (!rspecs[i]) {
- ret = WIMLIB_ERR_NOMEM;
- goto out_free_rspecs;
- }
- }
-
- ret = do_load_solid_info(wim, rspecs, num_rspecs, entries);
- if (ret)
- goto out_free_rspecs;
-
- *rspecs_ret = rspecs;
- *num_rspecs_ret = num_rspecs;
- return 0;
-
-out_free_rspecs:
- for (i = 0; i < num_rspecs; i++)
- FREE(rspecs[i]);
- FREE(rspecs);
- return ret;
-}
-
-/* Given a 'struct wim_lookup_table_entry' allocated for a stream entry with the
- * SOLID flag set, try to bind it to resource in the current solid run. */
-static int
-bind_stream_to_solid_resource(const struct wim_reshdr *reshdr,
- struct wim_lookup_table_entry *stream,
- struct wim_resource_spec **rspecs,
- size_t num_rspecs)
-{
- u64 offset = reshdr->offset_in_wim;
-
- /* XXX: This linear search will be slow in the degenerate case where the
- * number of solid resources in the run is huge. */
- stream->size = reshdr->size_in_wim;
- stream->flags = reshdr->flags;
- for (size_t i = 0; i < num_rspecs; i++) {
- if (offset + stream->size <= rspecs[i]->uncompressed_size) {
- stream->offset_in_res = offset;
- lte_bind_wim_resource_spec(stream, rspecs[i]);
- return 0;
- }
- offset -= rspecs[i]->uncompressed_size;
- }
- ERROR("Stream could not be assigned to a solid resource");
- return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
-}
-
-static void
-free_solid_rspecs(struct wim_resource_spec **rspecs, size_t num_rspecs)
-{
- if (rspecs) {
- for (size_t i = 0; i < num_rspecs; i++)
- if (list_empty(&rspecs[i]->stream_list))
- FREE(rspecs[i]);
- FREE(rspecs);
- }
-}
-
-static int
-cmp_streams_by_offset_in_res(const void *p1, const void *p2)
-{
- const struct wim_lookup_table_entry *lte1, *lte2;
-
- lte1 = *(const struct wim_lookup_table_entry**)p1;
- lte2 = *(const struct wim_lookup_table_entry**)p2;
-
- return cmp_u64(lte1->offset_in_res, lte2->offset_in_res);
-}
-
-/* Validate the size and location of a WIM resource. */
-static int
-validate_resource(struct wim_resource_spec *rspec)
-{
- struct wim_lookup_table_entry *lte;
- bool out_of_order;
- u64 expected_next_offset;
- int ret;
-
- /* Verify that the resource itself has a valid offset and size. */
- if (rspec->offset_in_wim + rspec->size_in_wim < rspec->size_in_wim)
- goto invalid_due_to_overflow;
-
- /* Verify that each stream in the resource has a valid offset and size.
- */
- expected_next_offset = 0;
- out_of_order = false;
- list_for_each_entry(lte, &rspec->stream_list, rspec_node) {
- if (lte->offset_in_res + lte->size < lte->size ||
- lte->offset_in_res + lte->size > rspec->uncompressed_size)
- goto invalid_due_to_overflow;
-
- if (lte->offset_in_res >= expected_next_offset)
- expected_next_offset = lte->offset_in_res + lte->size;
- else
- out_of_order = true;
- }
-
- /* If the streams were not located at strictly increasing positions (not
- * allowing for overlap), sort them. Then make sure that none overlap.
- */
- if (out_of_order) {
- ret = sort_stream_list(&rspec->stream_list,
- offsetof(struct wim_lookup_table_entry,
- rspec_node),
- cmp_streams_by_offset_in_res);
- if (ret)
- return ret;
-
- expected_next_offset = 0;
- list_for_each_entry(lte, &rspec->stream_list, rspec_node) {
- if (lte->offset_in_res >= expected_next_offset)
- expected_next_offset = lte->offset_in_res + lte->size;
- else
- goto invalid_due_to_overlap;
- }
- }
-
- return 0;
-
-invalid_due_to_overflow:
- ERROR("Invalid resource entry (offset overflow)");
- return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
-
-invalid_due_to_overlap:
- ERROR("Invalid resource entry (streams in solid resource overlap)");
- return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
-}
-
-static int
-finish_solid_rspecs(struct wim_resource_spec **rspecs, size_t num_rspecs)
-{
- int ret = 0;
- for (size_t i = 0; i < num_rspecs; i++) {
- ret = validate_resource(rspecs[i]);
- if (ret)
- break;
- }
- free_solid_rspecs(rspecs, num_rspecs);
- return ret;
-}
-
-/*
- * Reads the lookup table from a WIM file. Usually, each entry specifies a
- * stream that the WIM file contains, along with its location and SHA1 message
- * digest.
- *
- * Saves lookup table entries for non-metadata streams in a hash table (set to
- * wim->lookup_table), and saves the metadata entry for each image in a special
- * per-image location (the wim->image_metadata array).
- *
- * This works for both version WIM_VERSION_DEFAULT (68864) and version
- * WIM_VERSION_SOLID (3584) WIMs. In the latter, a consecutive run of lookup
- * table entries that all have flag WIM_RESHDR_FLAG_SOLID (0x10) set is a "solid
- * run". A solid run logically contains zero or more resources, each of which
- * logically contains zero or more streams. Physically, in such a run, a
- * "lookup table entry" with uncompressed size SOLID_RESOURCE_MAGIC_NUMBER
- * (0x100000000) specifies a resource, whereas any other entry specifies a
- * stream. Within such a run, stream entries and resource entries need not be
- * in any particular order, except that the order of the resource entries is
- * important, as it affects how streams are assigned to resources. See the code
- * for details.
- *
- * Possible return values:
- * WIMLIB_ERR_SUCCESS (0)
- * WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY
- * WIMLIB_ERR_NOMEM
- *
- * Or an error code caused by failure to read the lookup table from the WIM
- * file.
- */
-int
-read_wim_lookup_table(WIMStruct *wim)
-{
- int ret;
- size_t num_entries;
- void *buf = NULL;
- struct wim_lookup_table *table = NULL;
- struct wim_lookup_table_entry *cur_entry = NULL;
- size_t num_duplicate_entries = 0;
- size_t num_wrong_part_entries = 0;
- u32 image_index = 0;
- struct wim_resource_spec **cur_solid_rspecs = NULL;
- size_t cur_num_solid_rspecs = 0;
-
- DEBUG("Reading lookup table.");
-
- /* Sanity check: lookup table entries are 50 bytes each. */
- BUILD_BUG_ON(sizeof(struct wim_lookup_table_entry_disk) !=
- WIM_LOOKUP_TABLE_ENTRY_DISK_SIZE);
-
- /* Calculate the number of entries in the lookup table. */
- num_entries = wim->hdr.lookup_table_reshdr.uncompressed_size /
- sizeof(struct wim_lookup_table_entry_disk);
-
- /* Read the lookup table into a buffer. */
- ret = wim_reshdr_to_data(&wim->hdr.lookup_table_reshdr, wim, &buf);
- if (ret)
- goto out;
-
- /* Allocate a hash table to map SHA1 message digests into stream
- * specifications. This is the in-memory "lookup table". */
- table = new_lookup_table(num_entries * 2 + 1);
- if (!table)
- goto oom;
-
- /* Allocate and initalize stream entries ('struct
- * wim_lookup_table_entry's) from the raw lookup table buffer. Each of
- * these entries will point to a 'struct wim_resource_spec' that
- * describes the underlying resource. In WIMs with version number
- * WIM_VERSION_SOLID, a resource may contain multiple streams.
- */
- for (size_t i = 0; i < num_entries; i++) {
- const struct wim_lookup_table_entry_disk *disk_entry =
- &((const struct wim_lookup_table_entry_disk*)buf)[i];
- struct wim_reshdr reshdr;
- u16 part_number;
-
- /* Get the resource header */
- get_wim_reshdr(&disk_entry->reshdr, &reshdr);
-
- DEBUG("reshdr: size_in_wim=%"PRIu64", "
- "uncompressed_size=%"PRIu64", "
- "offset_in_wim=%"PRIu64", "
- "flags=0x%02x",
- reshdr.size_in_wim, reshdr.uncompressed_size,
- reshdr.offset_in_wim, reshdr.flags);
-
- /* Ignore SOLID flag if it isn't supposed to be used in this WIM
- * version. */
- if (wim->hdr.wim_version == WIM_VERSION_DEFAULT)
- reshdr.flags &= ~WIM_RESHDR_FLAG_SOLID;
-
- /* Allocate a new 'struct wim_lookup_table_entry'. */
- cur_entry = new_lookup_table_entry();
- if (!cur_entry)
- goto oom;
-
- /* Get the part number, reference count, and hash. */
- part_number = le16_to_cpu(disk_entry->part_number);
- cur_entry->refcnt = le32_to_cpu(disk_entry->refcnt);
- copy_hash(cur_entry->hash, disk_entry->hash);
-
- if (reshdr.flags & WIM_RESHDR_FLAG_SOLID) {
-
- /* SOLID entry */
-
- if (!cur_solid_rspecs) {
- /* Starting new run */
- ret = load_solid_info(wim, disk_entry,
- num_entries - i,
- &cur_solid_rspecs,
- &cur_num_solid_rspecs);
- if (ret)
- goto out;
- }
-
- if (reshdr.uncompressed_size == SOLID_RESOURCE_MAGIC_NUMBER) {
- /* Resource entry, not stream entry */
- goto free_cur_entry_and_continue;
- }
-
- /* Stream entry */
-
- ret = bind_stream_to_solid_resource(&reshdr,
- cur_entry,
- cur_solid_rspecs,
- cur_num_solid_rspecs);
- if (ret)
- goto out;
-
- } else {
- /* Normal stream/resource entry; SOLID not set. */
-
- struct wim_resource_spec *rspec;
-
- if (unlikely(cur_solid_rspecs)) {
- /* This entry terminated a solid run. */
- ret = finish_solid_rspecs(cur_solid_rspecs,
- cur_num_solid_rspecs);
- cur_solid_rspecs = NULL;
- if (ret)
- goto out;
- }
-
- /* How to handle an uncompressed resource with its
- * uncompressed size different from its compressed size?
- *
- * Based on a simple test, WIMGAPI seems to handle this
- * as follows:
- *
- * if (size_in_wim > uncompressed_size) {
- * Ignore uncompressed_size; use size_in_wim
- * instead.
- * } else {
- * Honor uncompressed_size, but treat the part of
- * the file data above size_in_wim as all zeros.
- * }
- *
- * So we will do the same. */
- if (unlikely(!(reshdr.flags &
- WIM_RESHDR_FLAG_COMPRESSED) &&
- (reshdr.size_in_wim >
- reshdr.uncompressed_size)))
- {
- reshdr.uncompressed_size = reshdr.size_in_wim;
- }
-
- /* Set up a resource specification for this stream. */
-
- rspec = MALLOC(sizeof(struct wim_resource_spec));
- if (!rspec)
- goto oom;
-
- wim_res_hdr_to_spec(&reshdr, wim, rspec);
-
- cur_entry->offset_in_res = 0;
- cur_entry->size = reshdr.uncompressed_size;
- cur_entry->flags = reshdr.flags;
-
- lte_bind_wim_resource_spec(cur_entry, rspec);
- }
-
- /* cur_entry is now a stream bound to a resource. */
-
- /* Ignore entries with all zeroes in the hash field. */
- if (is_zero_hash(cur_entry->hash))
- goto free_cur_entry_and_continue;
-
- /* Verify that the part number matches that of the underlying
- * WIM file. */
- if (part_number != wim->hdr.part_number) {
- num_wrong_part_entries++;
- goto free_cur_entry_and_continue;
- }
-
- if (reshdr.flags & WIM_RESHDR_FLAG_METADATA) {
-
- /* Lookup table entry for a metadata resource. */
-
- /* Metadata entries with no references must be ignored.
- * See, for example, the WinPE WIMs from the WAIK v2.1.
- */
- if (cur_entry->refcnt == 0)
- goto free_cur_entry_and_continue;
-
- if (cur_entry->refcnt != 1) {
- /* We don't currently support this case due to
- * the complications of multiple images sharing
- * the same metadata resource or a metadata
- * resource also being referenced by files. */
- ERROR("Found metadata resource with refcnt != 1");
- ret = WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
- goto out;
- }
-
- if (wim->hdr.part_number != 1) {
- WARNING("Ignoring metadata resource found in a "
- "non-first part of the split WIM");
- goto free_cur_entry_and_continue;
- }
-
- /* The number of entries in the lookup table with
- * WIM_RESHDR_FLAG_METADATA set should be the same as
- * the image_count field in the WIM header. */
- if (image_index == wim->hdr.image_count) {
- WARNING("Found more metadata resources than images");
- goto free_cur_entry_and_continue;
- }
-
- /* Notice very carefully: We are assigning the metadata
- * resources to images in the same order in which their
- * lookup table entries occur on disk. (This is also
- * the behavior of Microsoft's software.) In
- * particular, this overrides the actual locations of
- * the metadata resources themselves in the WIM file as
- * well as any information written in the XML data. */
- DEBUG("Found metadata resource for image %"PRIu32" at "
- "offset %"PRIu64".",
- image_index + 1,
- reshdr.offset_in_wim);
-
- wim->image_metadata[image_index++]->metadata_lte = cur_entry;
- } else {
- /* Lookup table entry for a non-metadata stream. */
-
- /* Ignore this stream if it's a duplicate. */
- if (lookup_stream(table, cur_entry->hash)) {
- num_duplicate_entries++;
- goto free_cur_entry_and_continue;
- }
-
- /* Insert the stream into the in-memory lookup table,
- * keyed by its SHA1 message digest. */
- lookup_table_insert(table, cur_entry);
- }
-
- continue;
-
- free_cur_entry_and_continue:
- if (cur_solid_rspecs &&
- cur_entry->resource_location == RESOURCE_IN_WIM)
- lte_unbind_wim_resource_spec(cur_entry);
- free_lookup_table_entry(cur_entry);
- }
- cur_entry = NULL;
-
- if (cur_solid_rspecs) {
- /* End of lookup table terminated a solid run. */
- ret = finish_solid_rspecs(cur_solid_rspecs, cur_num_solid_rspecs);
- cur_solid_rspecs = NULL;
- if (ret)
- goto out;
- }
-
- if (wim->hdr.part_number == 1 && image_index != wim->hdr.image_count) {
- WARNING("Could not find metadata resources for all images");
- for (u32 i = image_index; i < wim->hdr.image_count; i++)
- put_image_metadata(wim->image_metadata[i], NULL);
- wim->hdr.image_count = image_index;
- }
-
- if (num_duplicate_entries > 0) {
- WARNING("Ignoring %zu duplicate streams in the WIM lookup table",
- num_duplicate_entries);
- }
-
- if (num_wrong_part_entries > 0) {
- WARNING("Ignoring %zu streams with wrong part number",
- num_wrong_part_entries);
- }
-
- DEBUG("Done reading lookup table.");
- wim->lookup_table = table;
- ret = 0;
- goto out_free_buf;
-
-oom:
- ERROR("Not enough memory to read lookup table!");
- ret = WIMLIB_ERR_NOMEM;
-out:
- free_solid_rspecs(cur_solid_rspecs, cur_num_solid_rspecs);
- free_lookup_table_entry(cur_entry);
- free_lookup_table(table);
-out_free_buf:
- FREE(buf);
- return ret;
-}
-
-static void
-put_wim_lookup_table_entry(struct wim_lookup_table_entry_disk *disk_entry,
- const struct wim_reshdr *out_reshdr,
- u16 part_number, u32 refcnt, const u8 *hash)
-{
- put_wim_reshdr(out_reshdr, &disk_entry->reshdr);
- disk_entry->part_number = cpu_to_le16(part_number);
- disk_entry->refcnt = cpu_to_le32(refcnt);
- copy_hash(disk_entry->hash, hash);
-}
-
-/* Note: the list of stream entries must be sorted so that all entries for the
- * same solid resource are consecutive. In addition, entries with
- * WIM_RESHDR_FLAG_METADATA set must be in the same order as the indices of the
- * underlying images. */
-int
-write_wim_lookup_table_from_stream_list(struct list_head *stream_list,
- struct filedes *out_fd,
- u16 part_number,
- struct wim_reshdr *out_reshdr,
- int write_resource_flags)
-{
- size_t table_size;
- struct wim_lookup_table_entry *lte;
- struct wim_lookup_table_entry_disk *table_buf;
- struct wim_lookup_table_entry_disk *table_buf_ptr;
- int ret;
- u64 prev_res_offset_in_wim = ~0ULL;
- u64 prev_uncompressed_size;
- u64 logical_offset;
-
- table_size = 0;
- list_for_each_entry(lte, stream_list, lookup_table_list) {
- table_size += sizeof(struct wim_lookup_table_entry_disk);
-
- if (lte->out_reshdr.flags & WIM_RESHDR_FLAG_SOLID &&
- lte->out_res_offset_in_wim != prev_res_offset_in_wim)
- {
- table_size += sizeof(struct wim_lookup_table_entry_disk);
- prev_res_offset_in_wim = lte->out_res_offset_in_wim;
- }
- }
-
- DEBUG("Writing WIM lookup table (size=%zu, offset=%"PRIu64")",
- table_size, out_fd->offset);
-
- table_buf = MALLOC(table_size);
- if (table_buf == NULL) {
- ERROR("Failed to allocate %zu bytes for temporary lookup table",
- table_size);
- return WIMLIB_ERR_NOMEM;
- }
- table_buf_ptr = table_buf;
-
- prev_res_offset_in_wim = ~0ULL;
- prev_uncompressed_size = 0;
- logical_offset = 0;
- list_for_each_entry(lte, stream_list, lookup_table_list) {
- if (lte->out_reshdr.flags & WIM_RESHDR_FLAG_SOLID) {
- struct wim_reshdr tmp_reshdr;
-
- /* Eww. When WIMGAPI sees multiple solid resources, it
- * expects the offsets to be adjusted as if there were
- * really only one solid resource. */
-
- if (lte->out_res_offset_in_wim != prev_res_offset_in_wim) {
- /* Put the resource entry for solid resource */
- tmp_reshdr.offset_in_wim = lte->out_res_offset_in_wim;
- tmp_reshdr.size_in_wim = lte->out_res_size_in_wim;
- tmp_reshdr.uncompressed_size = SOLID_RESOURCE_MAGIC_NUMBER;
- tmp_reshdr.flags = WIM_RESHDR_FLAG_SOLID;
-
- put_wim_lookup_table_entry(table_buf_ptr++,
- &tmp_reshdr,
- part_number,
- 1, zero_hash);
-
- logical_offset += prev_uncompressed_size;
-
- prev_res_offset_in_wim = lte->out_res_offset_in_wim;
- prev_uncompressed_size = lte->out_res_uncompressed_size;
- }
- tmp_reshdr = lte->out_reshdr;
- tmp_reshdr.offset_in_wim += logical_offset;
- put_wim_lookup_table_entry(table_buf_ptr++,
- &tmp_reshdr,
- part_number,
- lte->out_refcnt,
- lte->hash);
- } else {
- put_wim_lookup_table_entry(table_buf_ptr++,
- <e->out_reshdr,
- part_number,
- lte->out_refcnt,
- lte->hash);
- }
-
- }
- wimlib_assert((u8*)table_buf_ptr - (u8*)table_buf == table_size);
-
- /* Write the lookup table uncompressed. Although wimlib can handle a
- * compressed lookup table, MS software cannot. */
- ret = write_wim_resource_from_buffer(table_buf,
- table_size,
- WIM_RESHDR_FLAG_METADATA,
- out_fd,
- WIMLIB_COMPRESSION_TYPE_NONE,
- 0,
- out_reshdr,
- NULL,
- write_resource_flags);
- FREE(table_buf);
- DEBUG("ret=%d", ret);
- return ret;
-}
-
-/* Allocate a stream entry for the contents of the buffer, or re-use an existing
- * entry in @lookup_table for the same stream. */
-struct wim_lookup_table_entry *
-new_stream_from_data_buffer(const void *buffer, size_t size,
- struct wim_lookup_table *lookup_table)
-{
- u8 hash[SHA1_HASH_SIZE];
- struct wim_lookup_table_entry *lte, *existing_lte;
-
- sha1_buffer(buffer, size, hash);
- existing_lte = lookup_stream(lookup_table, hash);
- if (existing_lte) {
- wimlib_assert(existing_lte->size == size);
- lte = existing_lte;
- lte->refcnt++;
- } else {
- void *buffer_copy;
- lte = new_lookup_table_entry();
- if (lte == NULL)
- return NULL;
- buffer_copy = memdup(buffer, size);
- if (buffer_copy == NULL) {
- free_lookup_table_entry(lte);
- return NULL;
- }
- lte->resource_location = RESOURCE_IN_ATTACHED_BUFFER;
- lte->attached_buffer = buffer_copy;
- lte->size = size;
- copy_hash(lte->hash, hash);
- lookup_table_insert(lookup_table, lte);
- }
- return lte;
-}
-
-/* Calculate the SHA1 message digest of a stream and move it from the list of
- * unhashed streams to the stream lookup table, possibly joining it with an
- * existing lookup table entry for an identical stream.
- *
- * @lte: An unhashed lookup table entry.
- * @lookup_table: Lookup table for the WIM.
- * @lte_ret: On success, write a pointer to the resulting lookup table
- * entry to this location. This will be the same as @lte
- * if it was inserted into the lookup table, or different if
- * a duplicate stream was found.
- *
- * Returns 0 on success; nonzero if there is an error reading the stream.
- */
-int
-hash_unhashed_stream(struct wim_lookup_table_entry *lte,
- struct wim_lookup_table *lookup_table,
- struct wim_lookup_table_entry **lte_ret)
-{
- int ret;
- struct wim_lookup_table_entry *duplicate_lte;
- struct wim_lookup_table_entry **back_ptr;
-
- wimlib_assert(lte->unhashed);
-
- /* back_ptr must be saved because @back_inode and @back_stream_id are in
- * union with the SHA1 message digest and will no longer be valid once
- * the SHA1 has been calculated. */
- back_ptr = retrieve_lte_pointer(lte);
-
- ret = sha1_stream(lte);
- if (ret)
- return ret;
-
- /* Look for a duplicate stream */
- duplicate_lte = lookup_stream(lookup_table, lte->hash);
- list_del(<e->unhashed_list);
- if (duplicate_lte) {
- /* We have a duplicate stream. Transfer the reference counts
- * from this stream to the duplicate and update the reference to
- * this stream (in an inode or ads_entry) to point to the
- * duplicate. The caller is responsible for freeing @lte if
- * needed. */
- wimlib_assert(!(duplicate_lte->unhashed));
- wimlib_assert(duplicate_lte->size == lte->size);
- duplicate_lte->refcnt += lte->refcnt;
- lte->refcnt = 0;
- *back_ptr = duplicate_lte;
- lte = duplicate_lte;
- } else {
- /* No duplicate stream, so we need to insert this stream into
- * the lookup table and treat it as a hashed stream. */
- lookup_table_insert(lookup_table, lte);
- lte->unhashed = 0;
- }
- *lte_ret = lte;
- return 0;
-}
-
-void
-lte_to_wimlib_resource_entry(const struct wim_lookup_table_entry *lte,
- struct wimlib_resource_entry *wentry)
-{
- memset(wentry, 0, sizeof(*wentry));
-
- wentry->uncompressed_size = lte->size;
- if (lte->resource_location == RESOURCE_IN_WIM) {
- wentry->part_number = lte->rspec->wim->hdr.part_number;
- if (lte->flags & WIM_RESHDR_FLAG_SOLID) {
- wentry->compressed_size = 0;
- wentry->offset = lte->offset_in_res;
- } else {
- wentry->compressed_size = lte->rspec->size_in_wim;
- wentry->offset = lte->rspec->offset_in_wim;
- }
- wentry->raw_resource_offset_in_wim = lte->rspec->offset_in_wim;
- /*wentry->raw_resource_uncompressed_size = lte->rspec->uncompressed_size;*/
- wentry->raw_resource_compressed_size = lte->rspec->size_in_wim;
- }
- copy_hash(wentry->sha1_hash, lte->hash);
- wentry->reference_count = lte->refcnt;
- wentry->is_compressed = (lte->flags & WIM_RESHDR_FLAG_COMPRESSED) != 0;
- wentry->is_metadata = (lte->flags & WIM_RESHDR_FLAG_METADATA) != 0;
- wentry->is_free = (lte->flags & WIM_RESHDR_FLAG_FREE) != 0;
- wentry->is_spanned = (lte->flags & WIM_RESHDR_FLAG_SPANNED) != 0;
- wentry->packed = (lte->flags & WIM_RESHDR_FLAG_SOLID) != 0;
-}
-
-struct iterate_lte_context {
- wimlib_iterate_lookup_table_callback_t cb;
- void *user_ctx;
-};
-
-static int
-do_iterate_lte(struct wim_lookup_table_entry *lte, void *_ctx)
-{
- struct iterate_lte_context *ctx = _ctx;
- struct wimlib_resource_entry entry;
-
- lte_to_wimlib_resource_entry(lte, &entry);
- return (*ctx->cb)(&entry, ctx->user_ctx);
-}
-
-/* API function documented in wimlib.h */
-WIMLIBAPI int
-wimlib_iterate_lookup_table(WIMStruct *wim, int flags,
- wimlib_iterate_lookup_table_callback_t cb,
- void *user_ctx)
-{
- if (flags != 0)
- return WIMLIB_ERR_INVALID_PARAM;
-
- struct iterate_lte_context ctx = {
- .cb = cb,
- .user_ctx = user_ctx,
- };
- if (wim_has_metadata(wim)) {
- int ret;
- for (int i = 0; i < wim->hdr.image_count; i++) {
- ret = do_iterate_lte(wim->image_metadata[i]->metadata_lte,
- &ctx);
- if (ret)
- return ret;
- }
- }
- return for_lookup_table_entry(wim->lookup_table, do_iterate_lte, &ctx);
-}
git://wimlib.net / wimlib / commitdiff