+void
+put_image_metadata(struct wim_image_metadata *imd,
+ struct wim_lookup_table *table)
+{
+ if (imd && --imd->refcnt == 0) {
+ destroy_image_metadata(imd, table, true);
+ FREE(imd);
+ }
+}
+
+/* Appends the specified image metadata structure to the array of image metadata
+ * for a WIM, and increments the image count. */
+int
+append_image_metadata(WIMStruct *wim, struct wim_image_metadata *imd)
+{
+ struct wim_image_metadata **imd_array;
+
+ DEBUG("Reallocating image metadata array for image_count = %u",
+ wim->hdr.image_count + 1);
+ imd_array = REALLOC(wim->image_metadata,
+ sizeof(wim->image_metadata[0]) * (wim->hdr.image_count + 1));
+
+ if (imd_array == NULL)
+ return WIMLIB_ERR_NOMEM;
+ wim->image_metadata = imd_array;
+ imd_array[wim->hdr.image_count++] = imd;
+ return 0;
+}
+
+
+struct wim_image_metadata *
+new_image_metadata(void)
+{
+ struct wim_image_metadata *imd;
+
+ imd = CALLOC(1, sizeof(*imd));
+ if (imd) {
+ imd->refcnt = 1;
+ INIT_LIST_HEAD(&imd->inode_list);
+ INIT_LIST_HEAD(&imd->unhashed_streams);
+ DEBUG("Created new image metadata (refcnt=1)");
+ } else {
+ ERROR_WITH_ERRNO("Failed to allocate new image metadata structure");
+ }
+ return imd;
+}
+
+struct wim_image_metadata **
+new_image_metadata_array(unsigned num_images)
+{
+ struct wim_image_metadata **imd_array;
+
+ DEBUG("Creating new image metadata array for %u images",
+ num_images);
+
+ imd_array = CALLOC(num_images, sizeof(imd_array[0]));
+
+ if (imd_array == NULL) {
+ ERROR("Failed to allocate memory for %u image metadata structures",
+ num_images);
+ return NULL;
+ }
+ for (unsigned i = 0; i < num_images; i++) {
+ imd_array[i] = new_image_metadata();
+ if (imd_array[i] == NULL) {
+ for (unsigned j = 0; j < i; j++)
+ put_image_metadata(imd_array[j], NULL);
+ FREE(imd_array);
+ return NULL;
+ }
+ }
+ return imd_array;
+}
+
+/* Checksum all streams that are unhashed (other than the metadata streams),
+ * merging them into the lookup table as needed. This is a no-op unless the
+ * library has previously used to add or mount an image using the same
+ * WIMStruct. */
+int
+wim_checksum_unhashed_streams(WIMStruct *wim)
+{
+ int ret;
+
+ if (!wim_has_metadata(wim))
+ return 0;
+ for (int i = 0; i < wim->hdr.image_count; i++) {
+ struct wim_lookup_table_entry *lte, *tmp;
+ struct wim_image_metadata *imd = wim->image_metadata[i];
+ image_for_each_unhashed_stream_safe(lte, tmp, imd) {
+ struct wim_lookup_table_entry *new_lte;
+ ret = hash_unhashed_stream(lte, wim->lookup_table, &new_lte);
+ if (ret)
+ return ret;
+ if (new_lte != lte)
+ free_lookup_table_entry(lte);
+ }
+ }
+ return 0;
+}
+
+/*
+ * can_modify_wim - Check if a given WIM is writeable. This is only the case if
+ * it meets the following three conditions:
+ *
+ * 1. Write access is allowed to the underlying file (if any) at the filesystem level.
+ * 2. The WIM is not part of a spanned set.
+ * 3. The WIM_HDR_FLAG_READONLY flag is not set in the WIM header.
+ *
+ * Return value is 0 if writable; WIMLIB_ERR_WIM_IS_READONLY otherwise.
+ */
+int
+can_modify_wim(WIMStruct *wim)