fix(wayland): graceful exit on compositor disconnect

Replace 3 panicking unwrap() in cosmic-app-list/wayland_handler.rs
(event loop dispatch + 2 conn.flush in screencopy) with logged
errors that break/return None instead.

Wrap cosmic-applets/main.rs entry point in panic::catch_unwind to
catch panics propagating from libcosmic/iced/winit (which we cannot
patch locally without forking) when the COSMIC compositor closes
the Wayland connection at logout. This eliminates the cascade of
~12 SIGABRT coredumps observed at session shutdown.

Panic strategy is unwind (default), catch_unwind is sound here.

Leyoda 2026 – GPLv3

cosmic-app-list/src/wayland_handler.rs

@@ -388,7 +388,10 @@ impl CaptureData {
                 },
             )
             .unwrap();
-        self.conn.flush().unwrap();
+        if let Err(err) = self.conn.flush() {
+            tracing::error!("Wayland flush failed during screencopy session create: {err}");
+            return None;
+        }
 
         let formats = session
             .wait_while(|data| data.formats.is_none())
@@ -437,7 +440,10 @@ impl CaptureData {
                 session: capture_session.clone(),
             },
         );
-        self.conn.flush().unwrap();
+        if let Err(err) = self.conn.flush() {
+            tracing::error!("Wayland flush failed during screencopy capture: {err}");
+            return None;
+        }
 
         // TODO: wait for server to release buffer?
         let res = session
@@ -709,7 +715,10 @@ pub(crate) fn wayland_handler(
         if app_data.exit {
             break;
         }
-        event_loop.dispatch(None, &mut app_data).unwrap();
+        if let Err(err) = event_loop.dispatch(None, &mut app_data) {
+            tracing::error!("Wayland event loop terminated: {err}");
+            break;
+        }
     }
 }
 

cosmic-applets/src/main.rs

@@ -12,26 +12,44 @@ fn main() -> cosmic::iced::Result {
     };
 
     let start = applet.rfind('/').map_or(0, |v| v + 1);
-    let cmd = &applet.as_str()[start..];
+    let cmd = applet.as_str()[start..].to_string();
 
     tracing::info!("Starting `{cmd}` with version {VERSION}");
 
-    match cmd {
-        "cosmic-app-list" => cosmic_app_list::run(),
-        "cosmic-applet-a11y" => cosmic_applet_a11y::run(),
-        "cosmic-applet-audio" => cosmic_applet_audio::run(),
-        "cosmic-applet-battery" => cosmic_applet_battery::run(),
-        "cosmic-applet-bluetooth" => cosmic_applet_bluetooth::run(),
-        "cosmic-applet-minimize" => cosmic_applet_minimize::run(),
-        "cosmic-applet-network" => cosmic_applet_network::run(),
-        "cosmic-applet-notifications" => cosmic_applet_notifications::run(),
-        "cosmic-applet-power" => cosmic_applet_power::run(),
-        "cosmic-applet-status-area" => cosmic_applet_status_area::run(),
-        "cosmic-applet-tiling" => cosmic_applet_tiling::run(),
-        "cosmic-applet-time" => cosmic_applet_time::run(),
-        "cosmic-applet-workspaces" => cosmic_applet_workspaces::run(),
-        "cosmic-applet-input-sources" => cosmic_applet_input_sources::run(),
-        "cosmic-panel-button" => cosmic_panel_button::run(),
-        _ => Ok(()),
+    let cmd_for_run = cmd.clone();
+    let result = std::panic::catch_unwind(std::panic::AssertUnwindSafe(move || {
+        match cmd_for_run.as_str() {
+            "cosmic-app-list" => cosmic_app_list::run(),
+            "cosmic-applet-a11y" => cosmic_applet_a11y::run(),
+            "cosmic-applet-audio" => cosmic_applet_audio::run(),
+            "cosmic-applet-battery" => cosmic_applet_battery::run(),
+            "cosmic-applet-bluetooth" => cosmic_applet_bluetooth::run(),
+            "cosmic-applet-minimize" => cosmic_applet_minimize::run(),
+            "cosmic-applet-network" => cosmic_applet_network::run(),
+            "cosmic-applet-notifications" => cosmic_applet_notifications::run(),
+            "cosmic-applet-power" => cosmic_applet_power::run(),
+            "cosmic-applet-status-area" => cosmic_applet_status_area::run(),
+            "cosmic-applet-tiling" => cosmic_applet_tiling::run(),
+            "cosmic-applet-time" => cosmic_applet_time::run(),
+            "cosmic-applet-workspaces" => cosmic_applet_workspaces::run(),
+            "cosmic-applet-input-sources" => cosmic_applet_input_sources::run(),
+            "cosmic-panel-button" => cosmic_panel_button::run(),
+            _ => Ok(()),
+        }
+    }));
+
+    match result {
+        Ok(r) => r,
+        Err(payload) => {
+            let msg = payload
+                .downcast_ref::<&str>()
+                .map(|s| s.to_string())
+                .or_else(|| payload.downcast_ref::<String>().cloned())
+                .unwrap_or_else(|| "<non-string panic>".to_string());
+            tracing::error!(
+                "`{cmd}` panicked (likely compositor disconnect), exiting cleanly: {msg}"
+            );
+            Ok(())
+        }
     }
 }