求助关于 PHP -leveldb

最近想把 php-leveldb 的扩展升级到 PHP7 （作者很久没维护更新了），渣渣第一次改扩展，碰到很多问题， 比如： https://github.com/reeze/php-leveldb/blob/master/leveldb.c 这个文件 82 行的 php_leveldb_obj_new

#define php_leveldb_obj_new(obj, class_type)					\
  zend_object_value retval;										\
  obj *intern;													\
																\
  intern = (obj *)emalloc(sizeof(obj));               			\
  memset(intern, 0, sizeof(obj));                          		\
                                                                \
  zend_object_std_init(&intern->std, class_type TSRMLS_CC);     \
  init_properties(intern);										\
                                                                \
  retval.handle = zend_objects_store_put(intern,				\
     (zend_objects_store_dtor_t) zend_objects_destroy_object,	\
     php_##obj##_free, NULL TSRMLS_CC);							\
  retval.handlers = &leveldb_default_handlers;					\
                                                                \
  return retval;

中调用 zend_objects_store_put 函数，在 PHP5 中我看了下第三个参数的类型是  zend_objects_free_object_storage_t，

ZEND_API zend_object_handle zend_objects_store_put(void *object, zend_objects_store_dtor_t dtor, zend_objects_free_object_storage_t free_storage, zend_objects_store_clone_t clone TSRMLS_DC)
{
	zend_object_handle handle;
	struct _store_object *obj;

	if (EG(objects_store).free_list_head != -1) {
		handle = EG(objects_store).free_list_head;
		EG(objects_store).free_list_head = EG(objects_store).object_buckets[handle].bucket.free_list.next;
	} else {
		if (EG(objects_store).top == EG(objects_store).size) {
			EG(objects_store).size <<= 1;
			EG(objects_store).object_buckets = (zend_object_store_bucket *) erealloc(EG(objects_store).object_buckets, EG(objects_store).size * sizeof(zend_object_store_bucket));
		}
		handle = EG(objects_store).top++;
	}
	obj = &EG(objects_store).object_buckets[handle].bucket.obj;
	EG(objects_store).object_buckets[handle].destructor_called = 0;
	EG(objects_store).object_buckets[handle].valid = 1;
	EG(objects_store).object_buckets[handle].apply_count = 0;

	obj->refcount = 1;
	GC_OBJ_INIT(obj);
	obj->object = object;
	obj->dtor = dtor?dtor:(zend_objects_store_dtor_t)zend_objects_destroy_object;
	obj->free_storage = free_storage;
	obj->clone = clone;
	obj->handlers = NULL;

#if ZEND_DEBUG_OBJECTS
	fprintf(stderr, "Allocated object id #%d\n", handle);
#endif
	return handle;
}

但是这边是 php_##obj##_free ,这个有点理解不能了 在 PHP7 里这个好像要放在custom_object_handlers.free_obj中，有点不明白，求指点