Implement stub mutter-x11-interop

Allows xdp-gnome dialogs to work with X11 clients.

Fixes https://github.com/YaLTeR/niri/issues/594

8 files changed, 154 insertions, 2 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 66763334..b2e84d69 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2260,6 +2260,8 @@ dependencies = [
  "tracing-subscriber",
  "tracy-client",
  "url",
+ "wayland-backend",
+ "wayland-scanner",
  "xcursor",
  "xshell",
  "zbus",
diff --git a/Cargo.toml b/Cargo.toml
index 38bc2d46..6262d052 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -78,6 +78,8 @@ tracing-subscriber.workspace = true
 tracing.workspace = true
 tracy-client.workspace = true
 url = { version = "2.5.2", optional = true }
+wayland-backend = "0.3.6"
+wayland-scanner = "0.31.4"
 xcursor = "0.3.6"
 zbus = { version = "~3.15.2", optional = true }
 
diff --git a/resources/mutter-x11-interop.xml b/resources/mutter-x11-interop.xml
new file mode 100644
index 00000000..ae5bccda
--- /dev/null
+++ b/resources/mutter-x11-interop.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="mutter_x11_interop">
+  <description summary="X11 interoperability helper">
+    This protocol is intended to be used by the portal backend to map Wayland
+    dialogs as modal dialogs on top of X11 windows.
+  </description>
+
+  <interface name="mutter_x11_interop" version="1">
+    <description summary="X11 interoperability helper"/>
+
+    <request name="destroy" type="destructor"/>
+
+    <request name="set_x11_parent">
+      <arg name="surface" type="object" interface="wl_surface"/>
+      <arg name="xwindow" type="uint"/>
+    </request>
+  </interface>
+</protocol>
diff --git a/src/handlers/mod.rs b/src/handlers/mod.rs
index b5c4392d..3e0bb18f 100644
--- a/src/handlers/mod.rs
+++ b/src/handlers/mod.rs
@@ -69,12 +69,13 @@ use crate::protocols::foreign_toplevel::{
     self, ForeignToplevelHandler, ForeignToplevelManagerState,
 };
 use crate::protocols::gamma_control::{GammaControlHandler, GammaControlManagerState};
+use crate::protocols::mutter_x11_interop::MutterX11InteropHandler;
 use crate::protocols::output_management::{OutputManagementHandler, OutputManagementManagerState};
 use crate::protocols::screencopy::{Screencopy, ScreencopyHandler, ScreencopyManagerState};
 use crate::utils::{output_size, send_scale_transform};
 use crate::{
-    delegate_foreign_toplevel, delegate_gamma_control, delegate_output_management,
-    delegate_screencopy,
+    delegate_foreign_toplevel, delegate_gamma_control, delegate_mutter_x11_interop,
+    delegate_output_management, delegate_screencopy,
 };
 
 impl SeatHandler for State {
@@ -580,3 +581,6 @@ impl OutputManagementHandler for State {
     }
 }
 delegate_output_management!(State);
+
+impl MutterX11InteropHandler for State {}
+delegate_mutter_x11_interop!(State);
diff --git a/src/niri.rs b/src/niri.rs
index 024df37e..9aec5ed1 100644
--- a/src/niri.rs
+++ b/src/niri.rs
@@ -118,6 +118,7 @@ use crate::ipc::server::IpcServer;
 use crate::layout::{Layout, LayoutElement as _, MonitorRenderElement};
 use crate::protocols::foreign_toplevel::{self, ForeignToplevelManagerState};
 use crate::protocols::gamma_control::GammaControlManagerState;
+use crate::protocols::mutter_x11_interop::MutterX11InteropManagerState;
 use crate::protocols::output_management::OutputManagementManagerState;
 use crate::protocols::screencopy::{Screencopy, ScreencopyBuffer, ScreencopyManagerState};
 use crate::pw_utils::{Cast, PipeWire};
@@ -233,6 +234,7 @@ pub struct Niri {
     pub security_context_state: SecurityContextState,
     pub gamma_control_manager_state: GammaControlManagerState,
     pub activation_state: XdgActivationState,
+    pub mutter_x11_interop_state: MutterX11InteropManagerState,
 
     pub seat: Seat<State>,
     /// Scancodes of the keys to suppress.
@@ -1602,6 +1604,8 @@ impl Niri {
                 is_tty && !client.get_data::<ClientState>().unwrap().restricted
             });
         let activation_state = XdgActivationState::new::<State>(&display_handle);
+        let mutter_x11_interop_state =
+            MutterX11InteropManagerState::new::<State, _>(&display_handle, move |_| true);
 
         let mut seat: Seat<State> = seat_state.new_wl_seat(&display_handle, backend.seat_name());
         seat.add_keyboard(
@@ -1764,6 +1768,7 @@ impl Niri {
             security_context_state,
             gamma_control_manager_state,
             activation_state,
+            mutter_x11_interop_state,
 
             seat,
             keyboard_focus: KeyboardFocus::Layout { surface: None },
diff --git a/src/protocols/mod.rs b/src/protocols/mod.rs
index a58b48bf..3328fb7c 100644
--- a/src/protocols/mod.rs
+++ b/src/protocols/mod.rs
@@ -1,4 +1,7 @@
 pub mod foreign_toplevel;
 pub mod gamma_control;
+pub mod mutter_x11_interop;
 pub mod output_management;
 pub mod screencopy;
+
+pub mod raw;
diff --git a/src/protocols/mutter_x11_interop.rs b/src/protocols/mutter_x11_interop.rs
new file mode 100644
index 00000000..cce41f15
--- /dev/null
+++ b/src/protocols/mutter_x11_interop.rs
@@ -0,0 +1,93 @@
+use mutter_x11_interop::MutterX11Interop;
+use smithay::reexports::wayland_server::{
+    Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New, Resource,
+};
+
+use super::raw::mutter_x11_interop::v1::server::mutter_x11_interop;
+
+const VERSION: u32 = 1;
+
+pub struct MutterX11InteropManagerState {}
+
+pub struct MutterX11InteropManagerGlobalData {
+    filter: Box<dyn for<'c> Fn(&'c Client) -> bool + Send + Sync>,
+}
+
+pub trait MutterX11InteropHandler {}
+
+impl MutterX11InteropManagerState {
+    pub fn new<D, F>(display: &DisplayHandle, filter: F) -> Self
+    where
+        D: GlobalDispatch<MutterX11Interop, MutterX11InteropManagerGlobalData>,
+        D: Dispatch<MutterX11Interop, ()>,
+        D: MutterX11InteropHandler,
+        D: 'static,
+        F: for<'c> Fn(&'c Client) -> bool + Send + Sync + 'static,
+    {
+        let global_data = MutterX11InteropManagerGlobalData {
+            filter: Box::new(filter),
+        };
+        display.create_global::<D, MutterX11Interop, _>(VERSION, global_data);
+
+        Self {}
+    }
+}
+
+impl<D> GlobalDispatch<MutterX11Interop, MutterX11InteropManagerGlobalData, D>
+    for MutterX11InteropManagerState
+where
+    D: GlobalDispatch<MutterX11Interop, MutterX11InteropManagerGlobalData>,
+    D: Dispatch<MutterX11Interop, ()>,
+    D: MutterX11InteropHandler,
+    D: 'static,
+{
+    fn bind(
+        _state: &mut D,
+        _handle: &DisplayHandle,
+        _client: &Client,
+        manager: New<MutterX11Interop>,
+        _manager_state: &MutterX11InteropManagerGlobalData,
+        data_init: &mut DataInit<'_, D>,
+    ) {
+        data_init.init(manager, ());
+    }
+
+    fn can_view(client: Client, global_data: &MutterX11InteropManagerGlobalData) -> bool {
+        (global_data.filter)(&client)
+    }
+}
+
+impl<D> Dispatch<MutterX11Interop, (), D> for MutterX11InteropManagerState
+where
+    D: Dispatch<MutterX11Interop, ()>,
+    D: MutterX11InteropHandler,
+    D: 'static,
+{
+    fn request(
+        _state: &mut D,
+        _client: &Client,
+        _resource: &MutterX11Interop,
+        request: <MutterX11Interop as Resource>::Request,
+        _data: &(),
+        _dhandle: &DisplayHandle,
+        _data_init: &mut DataInit<'_, D>,
+    ) {
+        match request {
+            mutter_x11_interop::Request::Destroy => (),
+            mutter_x11_interop::Request::SetX11Parent { .. } => (),
+        }
+    }
+}
+
+#[macro_export]
+macro_rules! delegate_mutter_x11_interop {
+    ($(@<$( $lt:tt $( : $clt:tt $(+ $dlt:tt )* )? ),+>)? $ty: ty) => {
+        smithay::reexports::wayland_server::delegate_global_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            $crate::protocols::raw::mutter_x11_interop::v1::server::mutter_x11_interop::MutterX11Interop: $crate::protocols::mutter_x11_interop::MutterX11InteropManagerGlobalData
+        ] => $crate::protocols::mutter_x11_interop::MutterX11InteropManagerState);
+
+        smithay::reexports::wayland_server::delegate_dispatch!($(@< $( $lt $( : $clt $(+ $dlt )* )? ),+ >)? $ty: [
+            $crate::protocols::raw::mutter_x11_interop::v1::server::mutter_x11_interop::MutterX11Interop: ()
+        ] => $crate::protocols::mutter_x11_interop::MutterX11InteropManagerState);
+    };
+}
diff --git a/src/protocols/raw.rs b/src/protocols/raw.rs
new file mode 100644
index 00000000..fac1e4df
--- /dev/null
+++ b/src/protocols/raw.rs
@@ -0,0 +1,25 @@
+pub mod mutter_x11_interop {
+    pub mod v1 {
+        pub use self::generated::server;
+
+        mod generated {
+            pub mod server {
+                #![allow(dead_code, non_camel_case_types, unused_unsafe, unused_variables)]
+                #![allow(non_upper_case_globals, non_snake_case, unused_imports)]
+                #![allow(missing_docs, clippy::all)]
+
+                use smithay::reexports::wayland_server;
+                use wayland_server::protocol::*;
+
+                pub mod __interfaces {
+                    use smithay::reexports::wayland_server;
+                    use wayland_server::protocol::__interfaces::*;
+                    wayland_scanner::generate_interfaces!("resources/mutter-x11-interop.xml");
+                }
+                use self::__interfaces::*;
+
+                wayland_scanner::generate_server_code!("resources/mutter-x11-interop.xml");
+            }
+        }
+    }
+}