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, 1 insertions, 2 deletions

diff --git a/scripts/qapi-commands.py b/scripts/qapi-commands.py
index 77ecd47071..49d4ce2590 100644
--- a/scripts/qapi-commands.py
+++ b/scripts/qapi-commands.py
@@ -113,11 +113,10 @@ def gen_marshal(name, arg_type, ret_type):
 
     if arg_type and arg_type.members:
         ret += mcgen('''
-    QmpInputVisitor *qiv = qmp_input_visitor_new(QOBJECT(args), true);
     Visitor *v;
     %(c_name)s 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;