ddt_object_info
error = ddt_object_info(ddt, type, class, &doi);
VERIFY(ddt_object_info(ddt, type, class, &doi) == 0);
VERIFY(ddt_object_info(ddt, type, class, &doi) == 0);
extern int ddt_object_info(ddt_t *ddt, enum ddt_type type,