Print deprecation notice when running SUID

SUID privilege drop is needed for the "builtin"-backend of libseat,
which copied our old "direct" backend behavior for the sake of
compatibility and ease of transition.

libseat now has a better alternative in the form of seatd-launch. It
uses the normal seatd daemon and libseat backend and takes care of SUID
for us.

Add a soft deprecation warning to highlight our future intent of
removing this code. The deprecation cycle is needed to avoid surprises
when sway no longer drops privileges.

1 files changed, 3 insertions, 0 deletions

diff --git a/sway/main.c b/sway/main.c
index 6c71048b..b6f8a8bf 100644
--- a/sway/main.c
+++ b/sway/main.c
@@ -153,6 +153,9 @@ static void log_kernel(void) {
 
 static bool drop_permissions(void) {
         if (getuid() != geteuid() || getgid() != getegid()) {
+                sway_log(SWAY_ERROR, "!!! DEPRECATION WARNING: "
+                        "SUID privilege drop will be removed in a future release, please migrate to seatd-launch");
+
                 // Set the gid and uid in the correct order.
                 if (setgid(getgid()) != 0) {
                         sway_log(SWAY_ERROR, "Unable to drop root group, refusing to start");