tree-wide: introduce new SOCKADDR_UN_LEN() macro, and use it everywhere

The macro determines the right length of a AF_UNIX "struct sockaddr_un" to pass to
connect() or bind(). It automatically figures out if the socket refers to an
abstract namespace socket, or a socket in the file system, and properly handles
the full length of the path field.

This macro is not only safer, but also simpler to use, than the usual
offsetof() + strlen() logic.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/udev/udev-ctrl.c b/src/udev/udev-ctrl.c
index 962de22f43..f68a09d7a8 100644
--- a/src/udev/udev-ctrl.c
+++ b/src/udev/udev-ctrl.c
@@ -105,7 +105,7 @@ struct udev_ctrl *udev_ctrl_new_from_fd(struct udev *udev, int fd) {
 
         uctrl->saddr.un.sun_family = AF_LOCAL;
         strscpy(uctrl->saddr.un.sun_path, sizeof(uctrl->saddr.un.sun_path), "/run/udev/control");
-        uctrl->addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(uctrl->saddr.un.sun_path);
+        uctrl->addrlen = SOCKADDR_UN_LEN(uctrl->saddr.un);
         return uctrl;
 }