From ae2f100b380671e347b2517d0017eabc26ef90bf Mon Sep 17 00:00:00 2001
From: "Brian J. Tarricone" <brian@tarricone.org>
Date: Mon, 25 Sep 2023 11:08:27 -0700
Subject: [PATCH] Ensure gtk apps only run on X11

---
 dialog-gtk3/src/main.rs |  8 ++++++++
 settings/src/main.rs    | 10 +++++++++-
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/dialog-gtk3/src/main.rs b/dialog-gtk3/src/main.rs
index f6d564b..50b784b 100644
--- a/dialog-gtk3/src/main.rs
+++ b/dialog-gtk3/src/main.rs
@@ -77,6 +77,14 @@ fn main() -> anyhow::Result<()> {
     init_logging("BSCREENSAVER_DIALOG_GTK3_LOG");
     glib::log_set_default_handler(glib::rust_log_handler);
 
+    // Can't use the rust version as it requires gtk_init() to be
+    // called first, but the underlying C function requires that
+    // it hasn't.
+    let backends = CString::new("x11").unwrap();
+    unsafe {
+        gtk::gdk::ffi::gdk_set_allowed_backends(backends.as_ptr());
+    };
+
     let config = Configuration::load()?;
     let new_login_command =
         if config.new_login_command == NewLoginCommand::Disabled {
diff --git a/settings/src/main.rs b/settings/src/main.rs
index e8bc73d..a68d839 100644
--- a/settings/src/main.rs
+++ b/settings/src/main.rs
@@ -1,7 +1,7 @@
 use gtk::{glib, prelude::*};
 use glib::clone;
 use log::warn;
-use std::{env, process::exit, time::Duration};
+use std::{env, process::exit, time::Duration, ffi::CString};
 
 use bscreensaver_util::{init_logging, settings::Configuration, desktop::NewLoginCommand};
 
@@ -18,6 +18,14 @@ fn main() -> anyhow::Result<()> {
     init_logging("BSCREENSAVER_SETTINGS");
     let config = Configuration::load()?;
 
+    // Can't use the rust version as it requires gtk_init() to be
+    // called first, but the underlying C function requires that
+    // it hasn't.
+    let backends = CString::new("x11").unwrap();
+    unsafe {
+        gtk::gdk::ffi::gdk_set_allowed_backends(backends.as_ptr());
+    };
+
     let app = gtk::Application::builder()
         .application_id("org.spurint.bscreensaver-settings")
         .build();