[Qemu-devel] [PATCH v2] qom: fix inherited interfaces

[Paolo Bonzini <pbonzini@redhat.com>]

The interface type rework had two bugs with interfaces that are inherited
from a superclass.  First of all, the implementation type name was wrong
(for example it was subclass::superclass::interface rather than
just subclass::interface).  Second, interfaces not registering their
type anymore means that accessing superclass::interface by type name
will fail.

This can be fixed by pre-initializing ti->parent_type of subclass::interface
to superclass::interface.

Reported-by: Igor Mammedov <imammedo@redhat.com>
Tested-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
        Andreas, perhaps this can be squashed with
        'qom: do not register interface "types" in the type table'.

 include/qom/object.h |  1 +
 qom/object.c         | 19 +++++++++++--------
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/include/qom/object.h b/include/qom/object.h
index 5f78847..e0ff212 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -536,6 +536,7 @@ struct InterfaceClass
     ObjectClass parent_class;
     /*< private >*/
     ObjectClass *concrete_class;
+    Type interface_type;
 };
 
 #define TYPE_INTERFACE "interface"
diff --git a/qom/object.c b/qom/object.c
index 750bb62..f696814 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -215,22 +215,25 @@ static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
 
 static void type_initialize(TypeImpl *ti);
 
-static void type_initialize_interface(TypeImpl *ti, const char *parent)
+static void type_initialize_interface(TypeImpl *ti, TypeImpl *interface_type,
+                                      TypeImpl *parent_type)
 {
     InterfaceClass *new_iface;
     TypeInfo info = { };
     TypeImpl *iface_impl;
 
-    info.parent = parent;
-    info.name = g_strdup_printf("%s::%s", ti->name, info.parent);
+    info.parent = parent_type->name;
+    info.name = g_strdup_printf("%s::%s", ti->name, interface_type->name);
     info.abstract = true;
 
     iface_impl = type_new(&info);
+    iface_impl->parent_type = parent_type;
     type_initialize(iface_impl);
     g_free((char *)info.name);
 
     new_iface = (InterfaceClass *)iface_impl->class;
     new_iface->concrete_class = ti->class;
+    new_iface->interface_type = interface_type;
 
     ti->class->interfaces = g_slist_append(ti->class->interfaces,
                                            iface_impl->class);
@@ -260,8 +263,10 @@ static void type_initialize(TypeImpl *ti)
         ti->class->interfaces = NULL;
 
         for (e = parent->class->interfaces; e; e = e->next) {
-            ObjectClass *iface = e->data;
-            type_initialize_interface(ti, object_class_get_name(iface));
+            InterfaceClass *iface = e->data;
+            ObjectClass *klass = OBJECT_CLASS(iface);
+
+            type_initialize_interface(ti, iface->interface_type, klass->type);
         }
 
         for (i = 0; i < ti->num_interfaces; i++) {
@@ -278,7 +283,7 @@ static void type_initialize(TypeImpl *ti)
                 continue;
             }
 
-            type_initialize_interface(ti, ti->interfaces[i].typename);
+            type_initialize_interface(ti, t, t);
         }
     }
 
@@ -294,8 +299,6 @@ static void type_initialize(TypeImpl *ti)
     if (ti->class_init) {
         ti->class_init(ti->class, ti->class_data);
     }
-
-
 }
 
 static void object_init_with_type(Object *obj, TypeImpl *ti)
-- 
1.8.4.2