qapi: Add new visit_free() function

Making each visitor provide its own (awkwardly-named) FOO_cleanup()
is unusual, when we can instead have a polymorphic visit_free()
interface.  Over the next few patches, we can use the polymorphic
functions to eliminate the need for a FOO_get_visitor() function
for accessing specific visitor functionality, once everything can
be accessed directly through the Visitor* interfaces.

The dealloc visitor is the first one converted to completely use
the new entry point, since qapi_dealloc_visitor_cleanup() was the
only reason that qapi_dealloc_get_visitor() existed, and only
generated and testsuite code was even using it.  With the new
visit_free() entry point in place, we no longer need to expose
the QapiDeallocVisitor subtype through qapi_dealloc_visitor_new(),
and can get by with less generated code, with diffs that look like:

| void qapi_free_ACPIOSTInfo(ACPIOSTInfo *obj)
| {
|-    QapiDeallocVisitor *qdv;
|     Visitor *v;
|
|     if (!obj) {
|         return;
|     }
|
|-    qdv = qapi_dealloc_visitor_new();
|-    v = qapi_dealloc_get_visitor(qdv);
|+    v = qapi_dealloc_visitor_new();
|     visit_type_ACPIOSTInfo(v, NULL, &obj, NULL);
|-    qapi_dealloc_visitor_cleanup(qdv);
|+    visit_free(v);
|}

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-5-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
This commit is contained in:
Eric Blake 2016-06-09 10:48:35 -06:00 committed by Markus Armbruster
parent 1158bb2a05
commit 2c0ef9f411
15 changed files with 114 additions and 52 deletions

View file

@ -214,6 +214,13 @@ Visitor *qmp_output_get_visitor(QmpOutputVisitor *v)
return &v->visitor;
}
static void qmp_output_free(Visitor *v)
{
QmpOutputVisitor *qov = to_qov(v);
qmp_output_visitor_cleanup(qov);
}
void qmp_output_visitor_cleanup(QmpOutputVisitor *v)
{
QStackEntry *e, *tmp;
@ -246,6 +253,7 @@ QmpOutputVisitor *qmp_output_visitor_new(void)
v->visitor.type_number = qmp_output_type_number;
v->visitor.type_any = qmp_output_type_any;
v->visitor.type_null = qmp_output_type_null;
v->visitor.free = qmp_output_free;
QTAILQ_INIT(&v->stack);