x11: Implement LinuxApplicationExt (#1867)

This allows interacting with the primary selection in the X11 backend.

Signed-off-by: Uli Schlachter <psychon@znc.in>

Author: psychon

CHANGELOG.md

@@ -48,6 +48,7 @@ You can find its changes [documented below](#070---2021-01-01).
 - `has_focus` method on `WidgetPod` ([#1825] by [@ForLoveOfCats])
 - x11: Add support for getting and setting clipboard contents ([#1805], [#1851], and [#1866] by [@psychon])
 - Linux extension: primary_clipboard ([#1843] by [@Maan2003])
+- x11: Implement primary_clipboard ([#1867] by [@psychon])
 
 ### Changed
 
@@ -752,6 +753,7 @@ Last release without a changelog :(
 [#1863]: https://github.com/linebender/druid/pull/1863
 [#1865]: https://github.com/linebender/druid/pull/1865
 [#1866]: https://github.com/linebender/druid/pull/1866
+[#1867]: https://github.com/linebender/druid/pull/1867
 
 [Unreleased]: https://github.com/linebender/druid/compare/v0.7.0...master
 [0.7.0]: https://github.com/linebender/druid/compare/v0.6.0...v0.7.0

druid-shell/src/backend/x11/application.rs

@@ -79,6 +79,10 @@ use super::window::Window;
 //
 // The name of the clipboard selection; used for implementing copy&paste
 //
+// PRIMARY
+//
+// The name of the primary selection; used for implementing "paste the currently selected text"
+//
 // TARGETS
 //
 // A target for getting the selection contents that answers with a list of supported targets
@@ -99,6 +103,7 @@ x11rb::atom_manager! {
         _NET_WM_WINDOW_TYPE_TOOLTIP,
         _NET_WM_WINDOW_TYPE_DIALOG,
         CLIPBOARD,
+        PRIMARY,
         TARGETS,
         INCR,
     }
@@ -135,6 +140,8 @@ pub(crate) struct Application {
     pub(crate) cursors: Cursors,
     /// The clipboard implementation
     clipboard: Clipboard,
+    /// The clipboard implementation for the primary selection
+    primary: Clipboard,
     /// The default screen of the connected display.
     ///
     /// The connected display may also have additional screens.
@@ -292,6 +299,15 @@ impl Application {
             Rc::clone(&connection),
             screen_num,
             Rc::clone(&atoms),
+            atoms.CLIPBOARD,
+            Rc::clone(&pending_events),
+            Rc::clone(&timestamp),
+        );
+        let primary = Clipboard::new(
+            Rc::clone(&connection),
+            screen_num,
+            Rc::clone(&atoms),
+            atoms.PRIMARY,
             Rc::clone(&pending_events),
             Rc::clone(&timestamp),
         );
@@ -305,6 +321,7 @@ impl Application {
             idle_read,
             cursors,
             clipboard,
+            primary,
             idle_write,
             present_opcode,
             root_visual_type,
@@ -592,17 +609,26 @@ impl Application {
             Event::SelectionClear(ev) => {
                 self.clipboard
                     .handle_clear(*ev)
-                    .context("SELECTION_CLEAR event handling")?;
+                    .context("SELECTION_CLEAR event handling for clipboard")?;
+                self.primary
+                    .handle_clear(*ev)
+                    .context("SELECTION_CLEAR event handling for primary")?;
             }
             Event::SelectionRequest(ev) => {
                 self.clipboard
                     .handle_request(ev)
-                    .context("SELECTION_REQUEST event handling")?;
+                    .context("SELECTION_REQUEST event handling for clipboard")?;
+                self.primary
+                    .handle_request(ev)
+                    .context("SELECTION_REQUEST event handling for primary")?;
             }
             Event::PropertyNotify(ev) => {
                 self.clipboard
                     .handle_property_notify(*ev)
-                    .context("PROPERTY_NOTIFY event handling")?;
+                    .context("PROPERTY_NOTIFY event handling for clipboard")?;
+                self.primary
+                    .handle_property_notify(*ev)
+                    .context("PROPERTY_NOTIFY event handling for primary")?;
             }
             Event::Error(e) => {
                 // TODO: if an error is caused by the present extension, disable it and fall back
@@ -767,6 +793,12 @@ impl Application {
     }
 }
 
+impl crate::platform::linux::LinuxApplicationExt for crate::Application {
+    fn primary_clipboard(&self) -> crate::Clipboard {
+        self.backend_app.primary.clone().into()
+    }
+}
+
 /// Clears out our idle pipe; `idle_read` should be the reading end of a pipe that was opened with
 /// O_NONBLOCK.
 fn drain_idle_pipe(idle_read: RawFd) -> Result<(), Error> {

druid-shell/src/backend/x11/clipboard.rs

@@ -55,13 +55,15 @@ impl Clipboard {
         connection: Rc<XCBConnection>,
         screen_num: usize,
         atoms: Rc<AppAtoms>,
+        selection_name: Atom,
         event_queue: Rc<RefCell<VecDeque<Event>>>,
         timestamp: Rc<Cell<Timestamp>>,
     ) -> Self {
         Self(Rc::new(RefCell::new(ClipboardState::new(
             connection,
             screen_num,
             atoms,
+            selection_name,
             event_queue,
             timestamp,
         ))))
@@ -122,6 +124,7 @@ struct ClipboardState {
     connection: Rc<XCBConnection>,
     screen_num: usize,
     atoms: Rc<AppAtoms>,
+    selection_name: Atom,
     event_queue: Rc<RefCell<VecDeque<Event>>>,
     timestamp: Rc<Cell<Timestamp>>,
     contents: Option<ClipboardContents>,
@@ -133,13 +136,15 @@ impl ClipboardState {
         connection: Rc<XCBConnection>,
         screen_num: usize,
         atoms: Rc<AppAtoms>,
+        selection_name: Atom,
         event_queue: Rc<RefCell<VecDeque<Event>>>,
         timestamp: Rc<Cell<Timestamp>>,
     ) -> Self {
         Self {
             connection,
             screen_num,
             atoms,
+            selection_name,
             event_queue,
             timestamp,
             contents: None,
@@ -153,16 +158,16 @@ impl ClipboardState {
         // Create a window for selection ownership and save the necessary state
         let contents = ClipboardContents::new(conn, self.screen_num, formats)?;
 
-        // Become CLIPBOARD selection owner
+        // Become selection owner of our selection
         conn.set_selection_owner(
             contents.owner_window,
-            self.atoms.CLIPBOARD,
+            self.selection_name,
             self.timestamp.get(),
         )?;
 
         // Check if we really are the selection owner; this might e.g. fail if our timestamp is too
         // old and some other program became the selection owner with a newer timestamp
-        let owner = conn.get_selection_owner(self.atoms.CLIPBOARD)?.reply()?;
+        let owner = conn.get_selection_owner(self.selection_name)?.reply()?;
         if owner.owner == contents.owner_window {
             // We are the new selection owner! Remember our contents for later.
             debug!("put_formats(): became selection owner");
@@ -269,7 +274,7 @@ impl ClipboardState {
 
         conn.convert_selection(
             window.window,
-            self.atoms.CLIPBOARD,
+            self.selection_name,
             format_atom,
             TRANSFER_ATOM,
             self.timestamp.get(),
@@ -351,6 +356,11 @@ impl ClipboardState {
     }
 
     fn handle_clear(&mut self, event: SelectionClearEvent) -> Result<(), ConnectionError> {
+        if event.selection != self.selection_name {
+            // This event is meant for another Clipboard instance
+            return Ok(());
+        }
+
         let window = self.contents.as_ref().map(|c| c.owner_window);
         if Some(event.owner) == window {
             // We lost ownership of the selection, clean up
@@ -362,6 +372,11 @@ impl ClipboardState {
     }
 
     fn handle_request(&mut self, event: &SelectionRequestEvent) -> Result<(), ReplyOrIdError> {
+        if event.selection != self.selection_name {
+            // This request is meant for another Clipboard instance
+            return Ok(());
+        }
+
         let conn = &*self.connection;
         let contents = match &self.contents {
             Some(contents) if contents.owner_window == event.owner => contents,

druid-shell/src/platform/linux.rs

@@ -32,7 +32,5 @@ mod test {
 
     use super::*;
     use static_assertions as sa;
-    // TODO(shell/x11): implement LinuxApplicationExt
-    #[cfg(not(feature = "x11"))]
     sa::assert_impl_all!(Application: LinuxApplicationExt);
 }