qmp-input-visitor: Favor new visit_free() function

Now that we have a polymorphic visit_free(), we no longer need
qmp_input_visitor_cleanup(); which in turn means we no longer
need to return a subtype from qmp_input_visitor_new() nor a
public upcast function.

Generated code changes to qmp-marshal.c look like:

|@@ -52,11 +52,10 @@ void qmp_marshal_add_fd(QDict *args, QOb
| {
|     Error *err = NULL;
|     AddfdInfo *retval;
|-    QmpInputVisitor *qiv = qmp_input_visitor_new(QOBJECT(args), true);
|     Visitor *v;
|     q_obj_add_fd_arg arg = {0};
|
|-    v = qmp_input_get_visitor(qiv);
|+    v = qmp_input_visitor_new(QOBJECT(args), true);
|     visit_start_struct(v, NULL, NULL, 0, &err);
|     if (err) {
|         goto out;

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-8-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/qmp.c b/qmp.c
index 7df6543871..b6d531ebe2 100644
--- a/qmp.c
+++ b/qmp.c
@@ -655,7 +655,7 @@ void qmp_object_add(const char *type, const char *id,
                     bool has_props, QObject *props, Error **errp)
 {
     const QDict *pdict = NULL;
-    QmpInputVisitor *qiv;
+    Visitor *v;
     Object *obj;
 
     if (props) {
@@ -666,10 +666,9 @@ void qmp_object_add(const char *type, const char *id,
         }
     }
 
-    qiv = qmp_input_visitor_new(props, true);
-    obj = user_creatable_add_type(type, id, pdict,
-                                  qmp_input_get_visitor(qiv), errp);
-    qmp_input_visitor_cleanup(qiv);
+    v = qmp_input_visitor_new(props, true);
+    obj = user_creatable_add_type(type, id, pdict, v, errp);
+    visit_free(v);
     if (obj) {
         object_unref(obj);
     }