qapi: Anonymous unions
The discriminator for anonymous unions is the data type. This allows to
have a union type that allows both of these:
{ 'file': 'my_existing_block_device_id' }
{ 'file': { 'filename': '/tmp/mydisk.qcow2', 'read-only': true } }
Unions like this are specified in the schema with an empty dict as
discriminator. For this example you could take:
{ 'union': 'BlockRef',
'discriminator': {},
'data': { 'definition': 'BlockOptions',
'reference': 'str' } }
{ 'type': 'ExampleObject',
'data: { 'file': 'BlockRef' } }
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
diff --git a/qapi/qmp-input-visitor.c b/qapi/qmp-input-visitor.c
index 70864a1..bf42c04 100644
--- a/qapi/qmp-input-visitor.c
+++ b/qapi/qmp-input-visitor.c
@@ -208,6 +208,19 @@
qmp_input_pop(qiv, errp);
}
+static void qmp_input_get_next_type(Visitor *v, int *kind, const int *qobjects,
+ const char *name, Error **errp)
+{
+ QmpInputVisitor *qiv = to_qiv(v);
+ QObject *qobj = qmp_input_get_object(qiv, name, false);
+
+ if (!qobj) {
+ error_set(errp, QERR_MISSING_PARAMETER, name ? name : "null");
+ return;
+ }
+ *kind = qobjects[qobject_type(qobj)];
+}
+
static void qmp_input_type_int(Visitor *v, int64_t *obj, const char *name,
Error **errp)
{
@@ -317,6 +330,7 @@
v->visitor.type_str = qmp_input_type_str;
v->visitor.type_number = qmp_input_type_number;
v->visitor.start_optional = qmp_input_start_optional;
+ v->visitor.get_next_type = qmp_input_get_next_type;
qmp_input_push(v, obj, NULL);
qobject_incref(obj);