api: make OwnedDisplayHandle wrap an opaque type

This will help in case we want to linger the event loop during drop
to prevent use after free in the consumers code.

src/platform_impl/linux/wayland/event_loop/mod.rs

@@ -16,7 +16,10 @@ use crate::cursor::OnlyCursorImage;
 use crate::dpi::LogicalSize;
 use crate::error::{EventLoopError, OsError, RequestError};
 use crate::event::{Event, StartCause, SurfaceSizeWriter, WindowEvent};
-use crate::event_loop::{ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents};
+use crate::event_loop::{
+    ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents,
+    OwnedDisplayHandle as CoreOwnedDisplayHandle,
+};
 use crate::platform::pump_events::PumpStatus;
 use crate::platform_impl::platform::min_timeout;
 use crate::platform_impl::PlatformCustomCursor;
@@ -49,7 +52,7 @@ pub struct EventLoop {
     wayland_dispatcher: WaylandDispatcher,
 
     /// Connection to the wayland server.
-    connection: Connection,
+    handle: Arc<OwnedDisplayHandle>,
 
     /// Event loop window target.
     active_event_loop: ActiveEventLoop,
@@ -117,8 +120,9 @@ impl EventLoop {
             })
             .map_err(|err| os_error!(err))?;
 
+        let handle = Arc::new(OwnedDisplayHandle::new(connection));
         let active_event_loop = ActiveEventLoop {
-            connection: connection.clone(),
+            handle: handle.clone(),
             wayland_dispatcher: wayland_dispatcher.clone(),
             event_loop_awakener,
             event_loop_proxy: EventLoopProxy::new(ping).into(),
@@ -133,7 +137,7 @@ impl EventLoop {
             compositor_updates: Vec::new(),
             buffer_sink: EventSink::default(),
             window_ids: Vec::new(),
-            connection,
+            handle,
             wayland_dispatcher,
             event_loop,
             active_event_loop,
@@ -227,7 +231,7 @@ impl EventLoop {
             //
             // Checking for flush error is essential to perform an exit with error, since
             // once we have a protocol error, we could get stuck retrying...
-            if self.connection.flush().is_err() {
+            if self.handle.connection.flush().is_err() {
                 self.set_exit_code(1);
                 return;
             }
@@ -561,8 +565,8 @@ pub struct ActiveEventLoop {
     /// Dispatcher of Wayland events.
     pub wayland_dispatcher: WaylandDispatcher,
 
-    /// Connection to the wayland server.
-    pub connection: Connection,
+    /// Handle for the underlying event loop.
+    pub handle: Arc<OwnedDisplayHandle>,
 }
 
 impl RootActiveEventLoop for ActiveEventLoop {
@@ -628,10 +632,8 @@ impl RootActiveEventLoop for ActiveEventLoop {
         None
     }
 
-    fn owned_display_handle(&self) -> crate::event_loop::OwnedDisplayHandle {
-        crate::event_loop::OwnedDisplayHandle {
-            platform: crate::platform_impl::OwnedDisplayHandle::Wayland(self.connection.clone()),
-        }
+    fn owned_display_handle(&self) -> CoreOwnedDisplayHandle {
+        CoreOwnedDisplayHandle::new(self.handle.clone())
     }
 
     fn rwh_06_handle(&self) -> &dyn rwh_06::HasDisplayHandle {
@@ -654,6 +656,22 @@ impl ActiveEventLoop {
 }
 
 impl rwh_06::HasDisplayHandle for ActiveEventLoop {
+    fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
+        self.handle.display_handle()
+    }
+}
+
+pub struct OwnedDisplayHandle {
+    pub(crate) connection: Connection,
+}
+
+impl OwnedDisplayHandle {
+    fn new(connection: Connection) -> Self {
+        Self { connection }
+    }
+}
+
+impl rwh_06::HasDisplayHandle for OwnedDisplayHandle {
     fn display_handle(&self) -> Result<rwh_06::DisplayHandle<'_>, rwh_06::HandleError> {
         use sctk::reexports::client::Proxy;
 

src/platform_impl/linux/wayland/window/mod.rs

@@ -87,7 +87,7 @@ impl Window {
         let compositor = state.compositor_state.clone();
         let xdg_activation =
             state.xdg_activation.as_ref().map(|activation_state| activation_state.global().clone());
-        let display = event_loop_window_target.connection.display();
+        let display = event_loop_window_target.handle.connection.display();
 
         let size: Size = attributes.surface_size.unwrap_or(LogicalSize::new(800., 600.).into());
 
@@ -103,7 +103,7 @@ impl Window {
             state.xdg_shell.create_window(surface.clone(), default_decorations, &queue_handle);
 
         let mut window_state = WindowState::new(
-            event_loop_window_target.connection.clone(),
+            event_loop_window_target.handle.clone(),
             &event_loop_window_target.queue_handle,
             &state,
             size,

src/platform_impl/linux/wayland/window/state.rs

@@ -10,7 +10,7 @@ use sctk::reexports::client::backend::ObjectId;
 use sctk::reexports::client::protocol::wl_seat::WlSeat;
 use sctk::reexports::client::protocol::wl_shm::WlShm;
 use sctk::reexports::client::protocol::wl_surface::WlSurface;
-use sctk::reexports::client::{Connection, Proxy, QueueHandle};
+use sctk::reexports::client::{Proxy, QueueHandle};
 use sctk::reexports::csd_frame::{
     DecorationsFrame, FrameAction, FrameClick, ResizeEdge, WindowState as XdgWindowState,
 };
@@ -31,6 +31,7 @@ use wayland_protocols_plasma::blur::client::org_kde_kwin_blur::OrgKdeKwinBlur;
 use crate::cursor::CustomCursor as RootCustomCursor;
 use crate::dpi::{LogicalPosition, LogicalSize, PhysicalSize, Size};
 use crate::error::{NotSupportedError, RequestError};
+use crate::platform_impl::wayland::event_loop::OwnedDisplayHandle;
 use crate::platform_impl::wayland::logical_to_physical_rounded;
 use crate::platform_impl::wayland::seat::{
     PointerConstraintsState, WinitPointerData, WinitPointerDataExt, ZwpTextInputV3Ext,
@@ -52,7 +53,7 @@ const MIN_WINDOW_SIZE: LogicalSize<u32> = LogicalSize::new(2, 1);
 /// The state of the window which is being updated from the [`WinitState`].
 pub struct WindowState {
     /// The connection to Wayland server.
-    pub connection: Connection,
+    pub handle: Arc<OwnedDisplayHandle>,
 
     /// The `Shm` to set cursor.
     pub shm: WlShm,
@@ -161,7 +162,7 @@ pub struct WindowState {
 impl WindowState {
     /// Create new window state.
     pub fn new(
-        connection: Connection,
+        handle: Arc<OwnedDisplayHandle>,
         queue_handle: &QueueHandle<WinitState>,
         winit_state: &WinitState,
         initial_size: Size,
@@ -183,7 +184,7 @@ impl WindowState {
             blur: None,
             blur_manager: winit_state.kwin_blur_manager.clone(),
             compositor,
-            connection,
+            handle,
             csd_fails: false,
             cursor_grab_mode: GrabState::new(),
             selected_cursor: Default::default(),
@@ -693,7 +694,7 @@ impl WindowState {
         }
 
         self.apply_on_pointer(|pointer, _| {
-            if pointer.set_cursor(&self.connection, cursor_icon).is_err() {
+            if pointer.set_cursor(&self.handle.connection, cursor_icon).is_err() {
                 warn!("Failed to set cursor to {:?}", cursor_icon);
             }
         })