qapi: Add qobject_is_equal()

This generic function (along with its implementations for different
types) determines whether two QObjects are equal.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20171114180128.17076-4-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

1 files changed, 9 insertions, 0 deletions

diff --git a/qobject/qnull.c b/qobject/qnull.c
index bc9fd31626..f6f55f11ea 100644
--- a/qobject/qnull.c
+++ b/qobject/qnull.c
@@ -20,3 +20,12 @@ QNull qnull_ = {
         .refcnt = 1,
     },
 };
+
+/**
+ * qnull_is_equal(): Always return true because any two QNull objects
+ * are equal.
+ */
+bool qnull_is_equal(const QObject *x, const QObject *y)
+{
+    return true;
+}