Add tree walking debug function

include/refcount/refcount.h

@@ -457,6 +457,34 @@ static inline bool refcount_remove_destructor(void *obj, void *key) {
 }
 
 // Debug Functions
+/**
+ * Callback used from #refcount_debug_context_walk_tree.
+ * @param cur The current object in the walk
+ * @param trail The parent objects, up to the root object
+ * @return True if the walk should stop, false otherwise
+ */
+typedef bool (*refcount_debug_walk_callback_t)(void *cur,
+                                               const RefcountList *trail,
+                                               void *user_data);
+
+bool refcount_debug_context_walk_tree(const RefcountContext *ctx, void *obj,
+                                      refcount_debug_walk_callback_t callback,
+                                      void *user_data);
+
+/**
+ * Same as #refcount_debug_context_walk_tree, but only operates on the global
+ * context.
+ * @param obj The root object
+ * @param callback The callback
+ * @param user_data Extra data to pass to the callback
+ * @return True if the walk ended early because a callback returned true, false
+ */
+static inline bool
+refcount_debug_walk_tree(void *obj, refcount_debug_walk_callback_t callback,
+                         void *user_data) {
+    return refcount_debug_context_walk_tree(refcount_default_context, obj,
+                                            callback, user_data);
+}
 
 uint64_t refcount_debug_context_count_object(const RefcountContext *ctx,
                                              void *obj, void *target);