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, 6 insertions, 8 deletions

diff --git a/qmp.c b/qmp.c
index 0a1fa19925..3ff6db79b9 100644
--- a/qmp.c
+++ b/qmp.c
@@ -210,7 +210,7 @@ ObjectPropertyInfoList *qmp_qom_list(const char *path, Error **errp)
     bool ambiguous = false;
     ObjectPropertyInfoList *props = NULL;
     ObjectProperty *prop;
-    ObjectPropertyIterator *iter;
+    ObjectPropertyIterator iter;
 
     obj = object_resolve_path(path, &ambiguous);
     if (obj == NULL) {
@@ -223,8 +223,8 @@ ObjectPropertyInfoList *qmp_qom_list(const char *path, Error **errp)
         return NULL;
     }
 
-    iter = object_property_iter_init(obj);
-    while ((prop = object_property_iter_next(iter))) {
+    object_property_iter_init(&iter, obj);
+    while ((prop = object_property_iter_next(&iter))) {
         ObjectPropertyInfoList *entry = g_malloc0(sizeof(*entry));
 
         entry->value = g_malloc0(sizeof(ObjectPropertyInfo));
@@ -234,7 +234,6 @@ ObjectPropertyInfoList *qmp_qom_list(const char *path, Error **errp)
         entry->value->name = g_strdup(prop->name);
         entry->value->type = g_strdup(prop->type);
     }
-    object_property_iter_free(iter);
 
     return props;
 }
@@ -506,7 +505,7 @@ DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
     ObjectClass *klass;
     Object *obj;
     ObjectProperty *prop;
-    ObjectPropertyIterator *iter;
+    ObjectPropertyIterator iter;
     DevicePropertyInfoList *prop_list = NULL;
 
     klass = object_class_by_name(typename);
@@ -535,8 +534,8 @@ DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
 
     obj = object_new(typename);
 
-    iter = object_property_iter_init(obj);
-    while ((prop = object_property_iter_next(iter))) {
+    object_property_iter_init(&iter, obj);
+    while ((prop = object_property_iter_next(&iter))) {
         DevicePropertyInfo *info;
         DevicePropertyInfoList *entry;
 
@@ -567,7 +566,6 @@ DevicePropertyInfoList *qmp_device_list_properties(const char *typename,
         entry->next = prop_list;
         prop_list = entry;
     }
-    object_property_iter_free(iter);
 
     object_unref(obj);