sd-bus: add 'offset' member for vtable methods

Defaults to zero, which retains the current behaviour.
Fixes #577

1 files changed, 8 insertions, 0 deletions

diff --git a/src/libelogind/sd-bus/bus-objects.c b/src/libelogind/sd-bus/bus-objects.c
index 7e3cd86f6..c25293e5e 100644
--- a/src/libelogind/sd-bus/bus-objects.c
+++ b/src/libelogind/sd-bus/bus-objects.c
@@ -68,6 +68,12 @@ static int node_vtable_get_userdata(
         return 1;
 }
 
+static void *vtable_method_convert_userdata(const sd_bus_vtable *p, void *u) {
+        assert(p);
+
+        return (uint8_t*) u + p->x.method.offset;
+}
+
 static void *vtable_property_convert_userdata(const sd_bus_vtable *p, void *u) {
         assert(p);
 
@@ -364,6 +370,8 @@ static int method_callbacks_run(
         if (bus->nodes_modified)
                 return 0;
 
+        u = vtable_method_convert_userdata(c->vtable, u);
+
         *found_object = true;
 
         if (c->last_iteration == bus->iteration_counter)