Patchwork [for-1.5,2/9] qom: allow casting of a NULL class

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Submitter Paolo Bonzini
Date May 10, 2013, 12:16 p.m.
Message ID <1368188203-3407-3-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/242967/
State New
Headers show

Comments

Paolo Bonzini - May 10, 2013, 12:16 p.m.
This mimics what we do in object_dynamic_cast_assert.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 qom/object.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

Patch

diff --git a/qom/object.c b/qom/object.c
index 75e6aac..35f4694 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -449,10 +449,16 @@  Object *object_dynamic_cast_assert(Object *obj, const char *typename)
 ObjectClass *object_class_dynamic_cast(ObjectClass *class,
                                        const char *typename)
 {
-    TypeImpl *target_type = type_get_by_name(typename);
-    TypeImpl *type = class->type;
     ObjectClass *ret = NULL;
+    TypeImpl *target_type;
+    TypeImpl *type;
 
+    if (!class) {
+        return NULL;
+    }
+
+    type = class->type;
+    target_type = type_get_by_name(typename);
     if (!target_type) {
         /* target class type unknown, so fail the cast */
         return NULL;
@@ -488,7 +494,7 @@  ObjectClass *object_class_dynamic_cast_assert(ObjectClass *class,
 {
     ObjectClass *ret = object_class_dynamic_cast(class, typename);
 
-    if (!ret) {
+    if (!ret && class) {
         fprintf(stderr, "Object %p is not an instance of type %s\n",
                 class, typename);
         abort();