qom: Introduce object_class_is_abstract()

This lets a caller check if an ObjectClass as returned by, e.g.,
object_class_by_name() is instantiatable.

Signed-off-by: Andreas Färber <afaerber@suse.de>
Cc: Anthony Liguori <anthony@codemonkey.ws>

2 files changed, 13 insertions, 0 deletions

diff --git a/include/qom/object.h b/include/qom/object.h
index 8e16ea8a44..48e80ba229 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -691,6 +691,14 @@ ObjectClass *object_class_get_parent(ObjectClass *klass);
 const char *object_class_get_name(ObjectClass *klass);
 
 /**
+ * object_class_is_abstract:
+ * @klass: The class to obtain the abstractness for.
+ *
+ * Returns: %true if @klass is abstract, %false otherwise.
+ */
+bool object_class_is_abstract(ObjectClass *klass);
+
+/**
  * object_class_by_name:
  * @typename: The QOM typename to obtain the class for.
  *
diff --git a/qom/object.c b/qom/object.c
index 03e6f24d28..e200282172 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -501,6 +501,11 @@ ObjectClass *object_get_class(Object *obj)
     return obj->class;
 }
 
+bool object_class_is_abstract(ObjectClass *klass)
+{
+    return klass->type->abstract;
+}
+
 const char *object_class_get_name(ObjectClass *klass)
 {
     return klass->type->name;