seat: track pressed buttons for the grab

src/wayland/seat/pointer.rs

@@ -20,6 +20,7 @@ struct PointerInternal {
     focus: Option<(Resource<WlSurface>, (f64, f64))>,
     location: (f64, f64),
     grab: GrabStatus,
+    pressed_buttons: Vec<u32>,
 }
 
 impl PointerInternal {
@@ -29,6 +30,7 @@ impl PointerInternal {
             focus: None,
             location: (0.0, 0.0),
             grab: GrabStatus::None,
+            pressed_buttons: Vec::new(),
         }
     }
 
@@ -146,7 +148,16 @@ impl PointerHandle {
     /// This will internally send the appropriate button event to the client
     /// objects matching with the currently focused surface.
     pub fn button(&self, button: u32, state: ButtonState, serial: u32, time: u32) {
-        self.inner.lock().unwrap().with_grab(|mut handle, grab| {
+        let mut inner = self.inner.lock().unwrap();
+        match state {
+            ButtonState::Pressed => {
+                inner.pressed_buttons.push(button);
+            }
+            ButtonState::Released => {
+                inner.pressed_buttons.retain(|b| *b != button);
+            }
+        }
+        inner.with_grab(|mut handle, grab| {
             grab.button(&mut handle, button, state, serial, time);
         });
     }
@@ -229,6 +240,14 @@ impl<'a> PointerInnerHandle<'a> {
         self.inner.location
     }
 
+    /// A list of the currently physically pressed buttons
+    ///
+    /// This still includes buttons that your grab have intercepted and not sent
+    /// to the client.
+    pub fn current_pressed(&self) -> &[u32] {
+        &self.inner.pressed_buttons
+    }
+
     /// Notify that the pointer moved
     ///
     /// You provide the new location of the pointer, in the form of:
@@ -542,7 +561,6 @@ impl PointerGrab for DefaultGrab {
         handle.set_grab(
             serial,
             ClickGrab {
-                buttons: vec![button],
                 current_focus,
                 pending_focus: None,
             },
@@ -559,7 +577,6 @@ impl PointerGrab for DefaultGrab {
 // In case the user maintains several simultaneous clicks, release
 // the grab once all are released.
 struct ClickGrab {
-    buttons: Vec<u32>,
     current_focus: Option<(Resource<WlSurface>, (f64, f64))>,
     pending_focus: Option<(Resource<WlSurface>, (f64, f64))>,
 }
@@ -585,12 +602,8 @@ impl PointerGrab for ClickGrab {
         serial: u32,
         time: u32,
     ) {
-        match state {
-            ButtonState::Pressed => self.buttons.push(button),
-            ButtonState::Released => self.buttons.retain(|b| *b != button),
-        }
         handle.button(button, state, serial, time);
-        if self.buttons.is_empty() {
+        if handle.current_pressed().len() == 0 {
             // no more buttons are pressed, release the grab
             handle.unset_grab();
             // restore the focus