qom: make object_ref/unref use a void * instead of Object *.

The object_ref/unref methods are intended for use with any subclass of
the base Object. Using "Object *" in the signature is not adding any
meaningful level of type safety, since callers simply use "OBJECT(ptr)"
and this expands to an unchecked cast "(Object *)".

By using "void *" we enable the object_unref() method to be used to
provide support for g_autoptr() with any subclass.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200723181410.3145233-2-berrange@redhat.com>
Message-Id: <20200831210740.126168-2-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

2 files changed, 6 insertions, 4 deletions

diff --git a/include/qom/object.h b/include/qom/object.h
index 0f3a606..1f8aa2d 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -1035,7 +1035,7 @@ GSList *object_class_get_list_sorted(const char *implements_type,
  * as its reference count is greater than zero.
  * Returns: @obj
  */
-Object *object_ref(Object *obj);
+Object *object_ref(void *obj);
 
 /**
  * object_unref:
@@ -1044,7 +1044,7 @@ Object *object_ref(Object *obj);
  * Decrease the reference count of a object.  A object cannot be freed as long
  * as its reference count is greater than zero.
  */
-void object_unref(Object *obj);
+void object_unref(void *obj);
 
 /**
  * object_property_try_add:
diff --git a/qom/object.c b/qom/object.c
index 00fdf89..b1822a2 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -1124,8 +1124,9 @@ GSList *object_class_get_list_sorted(const char *implements_type,
                         object_class_cmp);
 }
 
-Object *object_ref(Object *obj)
+Object *object_ref(void *objptr)
 {
+    Object *obj = OBJECT(objptr);
     if (!obj) {
         return NULL;
     }
@@ -1133,8 +1134,9 @@ Object *object_ref(Object *obj)
     return obj;
 }
 
-void object_unref(Object *obj)
+void object_unref(void *objptr)
 {
+    Object *obj = OBJECT(objptr);
     if (!obj) {
         return;
     }