qom: Change object property iterator API contract

Currently the ObjectProperty iterator API works as follows:

  ObjectPropertyIterator *iter;

  iter = object_property_iter_init(obj);
  while ((prop = object_property_iter_next(iter))) {
     ...
  }
  object_property_iter_free(iter);

This has the benefit that the ObjectPropertyIterator struct
can be opaque, but has the downside that callers need to
explicitly call a free function. It is also not in keeping
with iterator style used elsewhere in QEMU/GLib2.

This patch changes the API to use stack allocation instead:

  ObjectPropertyIterator iter;

  object_property_iter_init(&iter, obj);
  while ((prop = object_property_iter_next(&iter))) {
     ...
  }

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
[AF: Fused ObjectPropertyIterator struct with typedef]
Signed-off-by: Andreas Färber <afaerber@suse.de>

1 files changed, 3 insertions, 4 deletions

diff --git a/net/filter.c b/net/filter.c
index f777ba2899..5d90f83429 100644
--- a/net/filter.c
+++ b/net/filter.c
@@ -137,7 +137,7 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
     Error *local_err = NULL;
     char *str, *info;
     ObjectProperty *prop;
-    ObjectPropertyIterator *iter;
+    ObjectPropertyIterator iter;
     StringOutputVisitor *ov;
 
     if (!nf->netdev_id) {
@@ -174,8 +174,8 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
     QTAILQ_INSERT_TAIL(&nf->netdev->filters, nf, next);
 
     /* generate info str */
-    iter = object_property_iter_init(OBJECT(nf));
-    while ((prop = object_property_iter_next(iter))) {
+    object_property_iter_init(&iter, OBJECT(nf));
+    while ((prop = object_property_iter_next(&iter))) {
         if (!strcmp(prop->name, "type")) {
             continue;
         }
@@ -189,7 +189,6 @@ static void netfilter_complete(UserCreatable *uc, Error **errp)
         g_free(str);
         g_free(info);
     }
-    object_property_iter_free(iter);
 }
 
 static void netfilter_finalize(Object *obj)