Epoll (#20)

major update:
- remove threading overhead by resorting to an event driven design with mio as a backend for epoll
- Clients can now have an arbitrary amount of ip adresses and lan-mouse will automatically choose the correct one
- -> seemless switching between ethernet and wifi
- cli frontend + frontend adapter for future frontends

src/backend/consumer/x11.rs

@@ -1,49 +1,57 @@
-use std::{ptr, sync::mpsc::Receiver};
+use std::ptr;
 use x11::{xlib, xtest};
 
 use crate::{
-    client::{Client, ClientHandle},
-    event::Event,
+    client::ClientHandle,
+    event::Event, consumer::EventConsumer,
 };
 
-fn open_display() -> Option<*mut xlib::Display> {
-    unsafe {
-        match xlib::XOpenDisplay(ptr::null()) {
-            d if d == ptr::null::<xlib::Display>() as *mut xlib::Display => None,
-            display => Some(display),
+pub struct X11Consumer {
+    display: *mut xlib::Display,
+}
+
+impl X11Consumer {
+    pub fn new() -> Self {
+        let display = unsafe {
+            match xlib::XOpenDisplay(ptr::null()) {
+                d if d == ptr::null::<xlib::Display>() as *mut xlib::Display => None,
+                display => Some(display),
+            }
+        };
+        let display = display.expect("could not open display");
+        Self { display }
+    }
+
+    fn relative_motion(&self, dx: i32, dy: i32) {
+        unsafe {
+            xtest::XTestFakeRelativeMotionEvent(self.display, dx, dy, 0, 0);
+            xlib::XFlush(self.display);
         }
     }
 }
 
-fn relative_motion(display: *mut xlib::Display, dx: i32, dy: i32) {
-    unsafe {
-        xtest::XTestFakeRelativeMotionEvent(display, dx, dy, 0, 0);
-        xlib::XFlush(display);
-    }
-}
-
-pub fn run(event_rx: Receiver<(Event, ClientHandle)>, _clients: Vec<Client>) {
-    let display = match open_display() {
-        None => panic!("could not open display!"),
-        Some(display) => display,
-    };
-
-    loop {
-        match event_rx.recv().expect("event receiver unavailable").0 {
+impl EventConsumer for X11Consumer {
+    fn consume(&self, event: Event, _: ClientHandle) {
+        match event {
             Event::Pointer(pointer_event) => match pointer_event {
                 crate::event::PointerEvent::Motion {
                     time: _,
                     relative_x,
                     relative_y,
                 } => {
-                    relative_motion(display, relative_x as i32, relative_y as i32);
+                    self.relative_motion(relative_x as i32, relative_y as i32);
                 }
                 crate::event::PointerEvent::Button { .. } => {}
                 crate::event::PointerEvent::Axis { .. } => {}
                 crate::event::PointerEvent::Frame {} => {}
             },
             Event::Keyboard(_) => {}
-            Event::Release() => {}
+            _ => {}
         }
     }
+
+    fn notify(&mut self, _: crate::client::ClientEvent) {
+        // for our purposes it does not matter what client sent the event
+    }
 }
+