+/**
+ * htable_copy - duplicate a hash table.
+ * @dst: the hash table to overwrite
+ * @src: the hash table to copy
+ *
+ * Only fails on out-of-memory.
+ *
+ * Equivalent to (but faster than):
+ * if (!htable_init_sized(dst, src->rehash, src->priv, 1U << src->bits))
+ * return false;
+ * v = htable_first(src, &i);
+ * while (v) {
+ * htable_add(dst, v);
+ * v = htable_next(src, i);
+ * }
+ * return true;
+ */
+bool htable_copy(struct htable *dst, const struct htable *src);
+