WIP: remoting (#10085)

Release Notes:

- Added private alpha support for remote development. Please reach out to hi@zed.dev if you'd like to be part of shaping this feature.

crates/gpui/src/platform/linux/headless/client.rs

@@ -0,0 +1,98 @@
+use std::cell::RefCell;
+use std::ops::Deref;
+use std::rc::Rc;
+use std::time::{Duration, Instant};
+
+use calloop::{EventLoop, LoopHandle};
+use collections::HashMap;
+
+use util::ResultExt;
+
+use crate::platform::linux::LinuxClient;
+use crate::platform::{LinuxCommon, PlatformWindow};
+use crate::{
+    px, AnyWindowHandle, Bounds, CursorStyle, DisplayId, Modifiers, ModifiersChangedEvent, Pixels,
+    PlatformDisplay, PlatformInput, Point, ScrollDelta, Size, TouchPhase, WindowParams,
+};
+
+use calloop::{
+    generic::{FdWrapper, Generic},
+    RegistrationToken,
+};
+
+pub struct HeadlessClientState {
+    pub(crate) loop_handle: LoopHandle<'static, HeadlessClient>,
+    pub(crate) event_loop: Option<calloop::EventLoop<'static, HeadlessClient>>,
+    pub(crate) common: LinuxCommon,
+}
+
+#[derive(Clone)]
+pub(crate) struct HeadlessClient(Rc<RefCell<HeadlessClientState>>);
+
+impl HeadlessClient {
+    pub(crate) fn new() -> Self {
+        let event_loop = EventLoop::try_new().unwrap();
+
+        let (common, main_receiver) = LinuxCommon::new(event_loop.get_signal());
+
+        let handle = event_loop.handle();
+
+        handle.insert_source(main_receiver, |event, _, _: &mut HeadlessClient| {
+            if let calloop::channel::Event::Msg(runnable) = event {
+                runnable.run();
+            }
+        });
+
+        HeadlessClient(Rc::new(RefCell::new(HeadlessClientState {
+            event_loop: Some(event_loop),
+            loop_handle: handle,
+            common,
+        })))
+    }
+}
+
+impl LinuxClient for HeadlessClient {
+    fn with_common<R>(&self, f: impl FnOnce(&mut LinuxCommon) -> R) -> R {
+        f(&mut self.0.borrow_mut().common)
+    }
+
+    fn displays(&self) -> Vec<Rc<dyn PlatformDisplay>> {
+        vec![]
+    }
+
+    fn primary_display(&self) -> Option<Rc<dyn PlatformDisplay>> {
+        None
+    }
+
+    fn display(&self, id: DisplayId) -> Option<Rc<dyn PlatformDisplay>> {
+        None
+    }
+
+    fn open_window(
+        &self,
+        _handle: AnyWindowHandle,
+        params: WindowParams,
+    ) -> Box<dyn PlatformWindow> {
+        unimplemented!()
+    }
+
+    //todo(linux)
+    fn set_cursor_style(&self, _style: CursorStyle) {}
+
+    fn write_to_clipboard(&self, item: crate::ClipboardItem) {}
+
+    fn read_from_clipboard(&self) -> Option<crate::ClipboardItem> {
+        None
+    }
+
+    fn run(&self) {
+        let mut event_loop = self
+            .0
+            .borrow_mut()
+            .event_loop
+            .take()
+            .expect("App is already running");
+
+        event_loop.run(None, &mut self.clone(), |_| {}).log_err();
+    }
+}