diff --git a/qapi/qapi-dealloc-visitor.c b/qapi/qapi-dealloc-visitor.c index dc53545fa5..a14a1c7146 100644 --- a/qapi/qapi-dealloc-visitor.c +++ b/qapi/qapi-dealloc-visitor.c @@ -162,6 +162,31 @@ static void qapi_dealloc_type_enum(Visitor *v, int *obj, const char *strings[], { } +/* If there's no data present, the dealloc visitor has nothing to free. + * Thus, indicate to visitor code that the subsequent union fields can + * be skipped. This is not an error condition, since the cleanup of the + * rest of an object can continue unhindered, so leave errp unset in + * these cases. + * + * NOTE: In cases where we're attempting to deallocate an object that + * may have missing fields, the field indicating the union type may + * be missing. In such a case, it's possible we don't have enough + * information to differentiate data_present == false from a case where + * data *is* present but happens to be a scalar with a value of 0. + * This is okay, since in the case of the dealloc visitor there's no + * work that needs to done in either situation. + * + * The current inability in QAPI code to more thoroughly verify a union + * type in such cases will likely need to be addressed if we wish to + * implement this interface for other types of visitors in the future, + * however. + */ +static bool qapi_dealloc_start_union(Visitor *v, bool data_present, + Error **errp) +{ + return data_present; +} + Visitor *qapi_dealloc_get_visitor(QapiDeallocVisitor *v) { return &v->visitor; @@ -191,6 +216,7 @@ QapiDeallocVisitor *qapi_dealloc_visitor_new(void) v->visitor.type_str = qapi_dealloc_type_str; v->visitor.type_number = qapi_dealloc_type_number; v->visitor.type_size = qapi_dealloc_type_size; + v->visitor.start_union = qapi_dealloc_start_union; QTAILQ_INIT(&v->stack);