+ /* 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 packed resource overlap)");
+ return WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY;
+}
+
+static int
+finish_subpacks(struct wim_resource_spec **subpacks, size_t num_subpacks)
+{
+ int ret = 0;
+ for (size_t i = 0; i < num_subpacks; i++) {
+ ret = validate_resource(subpacks[i]);
+ if (ret)
+ break;
+ }
+ free_subpack_info(subpacks, num_subpacks);
+ 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_PACKED_STREAMS (3584) WIMs. In the latter, a consecutive run of
+ * lookup table entries that all have flag WIM_RESHDR_FLAG_PACKED_STREAMS (0x10)
+ * set is a "packed run". A packed 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
+ * WIM_PACK_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_subpacks = NULL;
+ size_t cur_num_subpacks = 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". */