util: Introduce virObjectGetRWLockableObj

Introduce a helper to handle the error path more cleanly. The same
as virObjectGetLockableObj in order to essentially follow the original
logic of commit 'b545f65d' to ensure that the input argument at least
has some validity before using.

Signed-off-by: John Ferlan <jferlan@redhat.com>

diff --git a/src/util/virobject.c b/src/util/virobject.c
index 4903393d001f69c825c2f220fa27ed58dc74ff35..c1e4474cafcc3b5768ee396c61f08c2d24053ce1 100644 (file)
--- a/src/util/virobject.c
+++ b/src/util/virobject.c
@@ -383,6 +383,22 @@ virObjectGetLockableObj(void *anyobj)
 }
 
 
+static virObjectRWLockablePtr
+virObjectGetRWLockableObj(void *anyobj)
+{
+    virObjectPtr obj;
+
+    if (virObjectIsClass(anyobj, virObjectRWLockableClass))
+        return anyobj;
+
+    obj = anyobj;
+    VIR_WARN("Object %p (%s) is not a virObjectRWLockable instance",
+              anyobj, obj ? obj->klass->name : "(unknown)");
+
+    return NULL;
+}
+
+
 /**
  * virObjectLock:
  * @anyobj: any instance of virObjectLockable or virObjectRWLockable
@@ -427,14 +443,12 @@ virObjectLock(void *anyobj)
 void
 virObjectRWLockRead(void *anyobj)
 {
-    if (virObjectIsClass(anyobj, virObjectRWLockableClass)) {
-        virObjectRWLockablePtr obj = anyobj;
-        virRWLockRead(&obj->lock);
-    } else {
-        virObjectPtr obj = anyobj;
-        VIR_WARN("Object %p (%s) is not a virObjectRWLockable instance",
-                 anyobj, obj ? obj->klass->name : "(unknown)");
-    }
+    virObjectRWLockablePtr obj = virObjectGetRWLockableObj(anyobj);
+
+    if (!obj)
+        return;
+
+    virRWLockRead(&obj->lock);
 }
 
 
@@ -458,14 +472,12 @@ virObjectRWLockRead(void *anyobj)
 void
 virObjectRWLockWrite(void *anyobj)
 {
-    if (virObjectIsClass(anyobj, virObjectRWLockableClass)) {
-        virObjectRWLockablePtr obj = anyobj;
-        virRWLockWrite(&obj->lock);
-    } else {
-        virObjectPtr obj = anyobj;
-        VIR_WARN("Object %p (%s) is not a virObjectRWLockable instance",
-                 anyobj, obj ? obj->klass->name : "(unknown)");
-    }
+    virObjectRWLockablePtr obj = virObjectGetRWLockableObj(anyobj);
+
+    if (!obj)
+        return;
+
+    virRWLockWrite(&obj->lock);
 }