}
}
-/* Decrements the reference count for the lookup table entry @lte. If its
- * reference count reaches 0, it is unlinked from the lookup table. If,
- * furthermore, the entry has no opened file descriptors associated with it, the
- * entry is freed. */
+/* 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 for the lookup table entry @lte, which must be
+ * inserted in the stream lookup table @table.
+ *
+ * If the reference count reaches 0, this may cause @lte to be destroyed.
+ * However, we may retain entries with 0 reference count. This does not affect
+ * correctness, but it prevents the entries for valid streams in a WIM archive,
+ * which will continue to be present after appending to the file, from being
+ * lost merely because we dropped all references to them.
+ */
void
lte_decrement_refcnt(struct wim_lookup_table_entry *lte,
struct wim_lookup_table *table)
unlink(lte->staging_file_name);
#endif
} else {
- lookup_table_unlink(table, lte);
+ if (!should_retain_lte(lte))
+ lookup_table_unlink(table, lte);
}
/* If FUSE mounts are enabled, we don't actually free the entry
#ifdef WITH_FUSE
if (lte->num_opened_fds == 0)
#endif
- free_lookup_table_entry(lte);
+ finalize_lte(lte);
}
}
wimlib_assert(lte->num_opened_fds != 0);
if (--lte->num_opened_fds == 0 && lte->refcnt == 0)
- free_lookup_table_entry(lte);
+ finalize_lte(lte);
}
#endif