Merge pull request #57 from Smithay/feature/egl_buffer

Feature: EGL Buffer support / Fix #12

.travis.yml

@@ -73,7 +73,6 @@ script:
             vagga cargo-$TRAVIS_RUST_VERSION doc --no-deps
         ;;
         "cargo-fmt")
-            vagga cargo-$TRAVIS_RUST_VERSION install -f rustfmt-nightly &&
             vagga cargo-$TRAVIS_RUST_VERSION fmt -- --write-mode=diff
         ;;
         "cargo-clippy")

Cargo.toml

@@ -7,31 +7,32 @@ description = "Smithay is a library for writing wayland compositors."
 repository = "https://github.com/Smithay/smithay"
 
 [dependencies]
-wayland-server = "0.12.0"
+wayland-server = "0.12.5"
+wayland-sys = "0.12.5"
 nix = "0.9.0"
 xkbcommon = "0.2.1"
 tempfile = "2.1.5"
-slog = { version = "2.0.0" }
-slog-stdlog = "2.0.0-0.2"
+slog = { version = "2.1.1" }
+slog-stdlog = "3.0.2"
 libloading = "0.4.0"
-wayland-client = { version = "0.9.9", optional = true }
-winit = { version = "0.8.2", optional = true }
+wayland-client = { version = "0.12.5", optional = true }
+winit = { version = "0.10.0", optional = true }
 drm = { version = "^0.3.1", optional = true }
-gbm = { version = "^0.3.0", optional = true, default-features = false, features = ["drm-support"] }
-glium = { version = "0.17.1", optional = true, default-features = false }
+gbm = { version = "^0.4.0", optional = true, default-features = false, features = ["drm-support"] }
+glium = { version = "0.19.0", optional = true, default-features = false }
 input = { version = "0.4.0", optional = true }
 udev = { version = "0.2.0", optional = true }
-rental = "0.4.11"
-wayland-protocols = { version = "0.12.0", features = ["unstable_protocols", "server"] }
+wayland-protocols = { version = "0.12.5", features = ["unstable_protocols", "server"] }
 image = "0.17.0"
 error-chain = "0.11.0"
+lazy_static = "1.0.0"
 
 [build-dependencies]
-gl_generator = "0.5"
+gl_generator = "0.7"
 
 [dev-dependencies]
-slog-term = "2.0"
-slog-async = "2.0"
+slog-term = "2.3"
+slog-async = "2.2"
 rand = "0.3"
 ctrlc = { version = "3.0", features = ["termination"] }
 

build.rs

@@ -29,7 +29,18 @@ fn main() {
             "EGL_MESA_platform_gbm",
             "EGL_EXT_platform_wayland",
             "EGL_EXT_platform_device",
+            "EGL_KHR_image_base",
         ],
-    ).write_bindings(gl_generator::StructGenerator, &mut file)
+    ).write_bindings(gl_generator::GlobalGenerator, &mut file)
+        .unwrap();
+
+    let mut file = File::create(&dest.join("gl_bindings.rs")).unwrap();
+    Registry::new(
+        Api::Gles2,
+        (3, 2),
+        Profile::Compatibility,
+        Fallbacks::None,
+        ["GL_OES_EGL_image"],
+    ).write_bindings(gl_generator::GlobalGenerator, &mut file)
         .unwrap();
 }

examples/drm.rs

@@ -13,25 +13,39 @@ extern crate slog_term;
 
 mod helpers;
 
+use drm::Device as BasicDevice;
 use drm::control::{Device as ControlDevice, ResourceInfo};
 use drm::control::connector::{Info as ConnectorInfo, State as ConnectorState};
 use drm::control::crtc;
 use drm::control::encoder::Info as EncoderInfo;
 use drm::result::Error as DrmError;
-use glium::Surface;
-use helpers::{init_shell, GliumDrawer, MyWindowMap, Roles, SurfaceData};
+use glium::{Blend, Surface};
+use helpers::{init_shell, Buffer, GliumDrawer, MyWindowMap, Roles, SurfaceData};
 use slog::{Drain, Logger};
 use smithay::backend::drm::{drm_device_bind, DrmBackend, DrmDevice, DrmHandler};
 use smithay::backend::graphics::egl::EGLGraphicsBackend;
+use smithay::backend::graphics::egl::wayland::{EGLDisplay, EGLWaylandExtensions, Format};
 use smithay::wayland::compositor::{CompositorToken, SubsurfaceRole, TraversalAction};
 use smithay::wayland::compositor::roles::Role;
-use smithay::wayland::shell::ShellState;
 use smithay::wayland::shm::init_shm_global;
 use std::cell::RefCell;
-use std::fs::OpenOptions;
+use std::fs::{File, OpenOptions};
+use std::os::unix::io::AsRawFd;
+use std::os::unix::io::RawFd;
 use std::rc::Rc;
 use std::time::Duration;
-use wayland_server::{StateToken, StateProxy};
+
+#[derive(Debug)]
+pub struct Card(File);
+
+impl AsRawFd for Card {
+    fn as_raw_fd(&self) -> RawFd {
+        self.0.as_raw_fd()
+    }
+}
+
+impl BasicDevice for Card {}
+impl ControlDevice for Card {}
 
 fn main() {
     // A logger facility, here we use the terminal for this example
@@ -50,8 +64,10 @@ fn main() {
     let mut options = OpenOptions::new();
     options.read(true);
     options.write(true);
-    let mut device: DrmDevice<GliumDrawer<DrmBackend>> =
-        DrmDevice::new_from_file(options.clone().open("/dev/dri/card0").unwrap(), log.clone()).unwrap();
+    let mut device = DrmDevice::new(
+        Card(options.clone().open("/dev/dri/card0").unwrap()),
+        log.clone(),
+    ).unwrap();
 
     // Get a set of all modesetting resource handles (excluding planes):
     let res_handles = device.resource_handles().unwrap();
@@ -60,9 +76,7 @@ fn main() {
     let connector_info = res_handles
         .connectors()
         .iter()
-        .map(|conn| {
-            ConnectorInfo::load_from_device(&device, *conn).unwrap()
-        })
+        .map(|conn| ConnectorInfo::load_from_device(&device, *conn).unwrap())
         .find(|conn| conn.connection_state() == ConnectorState::Connected)
         .unwrap();
 
@@ -81,27 +95,38 @@ fn main() {
     // Assuming we found a good connector and loaded the info into `connector_info`
     let mode = connector_info.modes()[0]; // Use first mode (usually highest resoltion, but in reality you should filter and sort and check and match with other connectors, if you use more then one.)
 
-    {
     // Initialize the hardware backend
-        let renderer = device
-            .create_backend(event_loop.state(), crtc, mode, vec![connector_info.handle()])
-            .unwrap();
-
+    let renderer = GliumDrawer::from(
+        device
+            .create_backend(crtc, mode, vec![connector_info.handle()])
+            .unwrap(),
+    );
+    {
         /*
          * Initialize glium
          */
-        let mut frame = event_loop.state().get(renderer).draw();
+        let mut frame = renderer.draw();
         frame.clear_color(0.8, 0.8, 0.9, 1.0);
         frame.finish().unwrap();
     }
 
+    let egl_display = Rc::new(RefCell::new(
+        if let Ok(egl_display) = renderer.bind_wl_display(&display) {
+            info!(log, "EGL hardware-acceleration enabled");
+            Some(egl_display)
+        } else {
+            None
+        },
+    ));
+
     /*
      * Initialize the globals
      */
 
     init_shm_global(&mut event_loop, vec![], log.clone());
 
-    let (compositor_token, shell_state_token, window_map) = init_shell(&mut event_loop, log.clone());
+    let (compositor_token, _shell_state_token, window_map) =
+        init_shell(&mut event_loop, log.clone(), egl_display.clone());
 
     /*
      * Add a listening socket:
@@ -117,9 +142,9 @@ fn main() {
         &mut event_loop,
         device_token,
         DrmHandlerImpl {
-            shell_state_token,
             compositor_token,
             window_map: window_map.clone(),
+            drawer: renderer,
             logger: log,
         },
     ).unwrap();
@@ -133,22 +158,21 @@ fn main() {
 }
 
 pub struct DrmHandlerImpl {
-    shell_state_token: StateToken<ShellState<SurfaceData, Roles, (), ()>>,
-    compositor_token: CompositorToken<SurfaceData, Roles, ()>,
+    compositor_token: CompositorToken<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>>,
     window_map: Rc<RefCell<MyWindowMap>>,
+    drawer: GliumDrawer<DrmBackend<Card>>,
     logger: ::slog::Logger,
 }
 
-impl DrmHandler<GliumDrawer<DrmBackend>> for DrmHandlerImpl {
-    fn ready<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, _device: &mut DrmDevice<GliumDrawer<DrmBackend>>,
-             backend: &StateToken<GliumDrawer<DrmBackend>>, _crtc: crtc::Handle, _frame: u32, _duration: Duration) {
-        let state = state.into();
-        let drawer = state.get(backend);
-        let mut frame = drawer.draw();
+impl DrmHandler<Card> for DrmHandlerImpl {
+    fn ready(
+        &mut self, _device: &mut DrmDevice<Card>, _crtc: crtc::Handle, _frame: u32, _duration: Duration
+    ) {
+        let mut frame = self.drawer.draw();
         frame.clear_color(0.8, 0.8, 0.9, 1.0);
         // redraw the frame, in a simple but inneficient way
         {
-            let screen_dimensions = drawer.get_framebuffer_dimensions();
+            let screen_dimensions = self.drawer.get_framebuffer_dimensions();
             self.window_map
                 .borrow()
                 .with_windows_from_bottom_to_top(|toplevel_surface, initial_place| {
@@ -159,18 +183,54 @@ impl DrmHandler<GliumDrawer<DrmBackend>> for DrmHandlerImpl {
                                 wl_surface,
                                 initial_place,
                                 |_surface, attributes, role, &(mut x, mut y)| {
-                                    if let Some((ref contents, (w, h))) = attributes.user_data.buffer {
                                     // there is actually something to draw !
+                                    if attributes.user_data.texture.is_none() {
+                                        let mut remove = false;
+                                        match attributes.user_data.buffer {
+                                            Some(Buffer::Egl { ref images }) => {
+                                                match images.format {
+                                                    Format::RGB | Format::RGBA => {
+                                                        attributes.user_data.texture =
+                                                            self.drawer.texture_from_egl(&images);
+                                                    }
+                                                    _ => {
+                                                        // we don't handle the more complex formats here.
+                                                        attributes.user_data.texture = None;
+                                                        remove = true;
+                                                    }
+                                                };
+                                            }
+                                            Some(Buffer::Shm { ref data, ref size }) => {
+                                                attributes.user_data.texture =
+                                                    Some(self.drawer.texture_from_mem(data, *size));
+                                            }
+                                            _ => {}
+                                        }
+                                        if remove {
+                                            attributes.user_data.buffer = None;
+                                        }
+                                    }
+
+                                    if let Some(ref texture) = attributes.user_data.texture {
                                         if let Ok(subdata) = Role::<SubsurfaceRole>::data(role) {
                                             x += subdata.x;
                                             y += subdata.y;
                                         }
-                                        drawer.render(
+                                        info!(self.logger, "Render window");
+                                        self.drawer.render_texture(
                                             &mut frame,
-                                            contents,
-                                            (w, h),
+                                            texture,
+                                            match *attributes.user_data.buffer.as_ref().unwrap() {
+                                                Buffer::Egl { ref images } => images.y_inverted,
+                                                Buffer::Shm { .. } => false,
+                                            },
+                                            match *attributes.user_data.buffer.as_ref().unwrap() {
+                                                Buffer::Egl { ref images } => (images.width, images.height),
+                                                Buffer::Shm { ref size, .. } => *size,
+                                            },
                                             (x, y),
                                             screen_dimensions,
+                                            Blend::alpha_blending(),
                                         );
                                         TraversalAction::DoChildren((x, y))
                                     } else {
@@ -186,8 +246,7 @@ impl DrmHandler<GliumDrawer<DrmBackend>> for DrmHandlerImpl {
         frame.finish().unwrap();
     }
 
-    fn error<'a, S: Into<StateProxy<'a>>>(&mut self, _state: S, _device: &mut DrmDevice<GliumDrawer<DrmBackend>>,
-             error: DrmError) {
+    fn error(&mut self, _device: &mut DrmDevice<Card>, error: DrmError) {
         panic!("{:?}", error);
     }
 }

examples/helpers/glium.rs

@@ -1,10 +1,14 @@
 use glium;
-use glium::{Frame, Surface};
+use glium::{Frame, GlObject, Surface};
 use glium::index::PrimitiveType;
+use glium::texture::{MipmapsOption, Texture2d, UncompressedFloatFormat};
 use smithay::backend::graphics::egl::EGLGraphicsBackend;
+use smithay::backend::graphics::egl::error::Result as EGLResult;
+use smithay::backend::graphics::egl::wayland::{EGLDisplay, EGLImages, EGLWaylandExtensions, Format};
 use smithay::backend::graphics::glium::GliumGraphicsBackend;
 use std::borrow::Borrow;
 use std::ops::Deref;
+use wayland_server::Display;
 
 #[derive(Copy, Clone)]
 struct Vertex {
@@ -106,21 +110,53 @@ impl<T: Into<GliumGraphicsBackend<T>> + EGLGraphicsBackend + 'static> From<T> fo
 }
 
 impl<F: EGLGraphicsBackend + 'static> GliumDrawer<F> {
-    pub fn render(&self, target: &mut glium::Frame, contents: &[u8], surface_dimensions: (u32, u32),
-                  surface_location: (i32, i32), screen_size: (u32, u32)) {
+    pub fn texture_from_mem(&self, contents: &[u8], surface_dimensions: (u32, u32)) -> Texture2d {
         let image = glium::texture::RawImage2d {
             data: contents.into(),
             width: surface_dimensions.0,
             height: surface_dimensions.1,
             format: glium::texture::ClientFormat::U8U8U8U8,
         };
-        let opengl_texture = glium::texture::Texture2d::new(&self.display, image).unwrap();
+        Texture2d::new(&self.display, image).unwrap()
+    }
 
+    pub fn texture_from_egl(&self, images: &EGLImages) -> Option<Texture2d> {
+        let format = match images.format {
+            Format::RGB => UncompressedFloatFormat::U8U8U8,
+            Format::RGBA => UncompressedFloatFormat::U8U8U8U8,
+            _ => return None,
+        };
+
+        let opengl_texture = Texture2d::empty_with_format(
+            &self.display,
+            format,
+            MipmapsOption::NoMipmap,
+            images.width,
+            images.height,
+        ).unwrap();
+        unsafe {
+            images
+                .bind_to_texture(0, opengl_texture.get_id())
+                .expect("Failed to bind to texture");
+        }
+        Some(opengl_texture)
+    }
+
+    pub fn render_texture(
+        &self, target: &mut glium::Frame, texture: &Texture2d, y_inverted: bool,
+        surface_dimensions: (u32, u32), surface_location: (i32, i32), screen_size: (u32, u32),
+        blending: glium::Blend,
+    ) {
         let xscale = 2.0 * (surface_dimensions.0 as f32) / (screen_size.0 as f32);
-        let yscale = -2.0 * (surface_dimensions.1 as f32) / (screen_size.1 as f32);
+        let mut yscale = -2.0 * (surface_dimensions.1 as f32) / (screen_size.1 as f32);
 
         let x = 2.0 * (surface_location.0 as f32) / (screen_size.0 as f32) - 1.0;
-        let y = 1.0 - 2.0 * (surface_location.1 as f32) / (screen_size.1 as f32);
+        let mut y = 1.0 - 2.0 * (surface_location.1 as f32) / (screen_size.1 as f32);
+
+        if y_inverted {
+            yscale = -yscale;
+            y -= surface_dimensions.1 as f32;
+        }
 
         let uniforms = uniform! {
             matrix: [
@@ -129,7 +165,7 @@ impl<F: EGLGraphicsBackend + 'static> GliumDrawer<F> {
                 [  0.0 ,   0.0  , 1.0, 0.0],
                 [   x  ,    y   , 0.0, 1.0]
             ],
-            tex: &opengl_texture
+            tex: texture,
         };
 
         target
@@ -138,7 +174,10 @@ impl<F: EGLGraphicsBackend + 'static> GliumDrawer<F> {
                 &self.index_buffer,
                 &self.program,
                 &uniforms,
-                &Default::default(),
+                &glium::DrawParameters {
+                    blend: blending,
+                    ..Default::default()
+                },
             )
             .unwrap();
     }
@@ -148,3 +187,9 @@ impl<F: EGLGraphicsBackend + 'static> GliumDrawer<F> {
         self.display.draw()
     }
 }
+
+impl<G: EGLWaylandExtensions + EGLGraphicsBackend + 'static> EGLWaylandExtensions for GliumDrawer<G> {
+    fn bind_wl_display(&self, display: &Display) -> EGLResult<EGLDisplay> {
+        self.display.bind_wl_display(display)
+    }
+}

examples/helpers/implementations.rs

@@ -1,10 +1,13 @@
 use super::WindowMap;
+use glium::texture::Texture2d;
 use rand;
+use smithay::backend::graphics::egl::wayland::{BufferAccessError, Format};
+use smithay::backend::graphics::egl::wayland::{EGLDisplay, EGLImages};
 use smithay::wayland::compositor::{compositor_init, CompositorToken, SurfaceAttributes,
                                    SurfaceUserImplementation};
 use smithay::wayland::shell::{shell_init, PopupConfigure, ShellState, ShellSurfaceRole,
                               ShellSurfaceUserImplementation, ToplevelConfigure};
-use smithay::wayland::shm::with_buffer_contents;
+use smithay::wayland::shm::with_buffer_contents as shm_buffer_contents;
 use std::cell::RefCell;
 use std::rc::Rc;
 use wayland_server::{EventLoop, StateToken};
@@ -13,18 +16,45 @@ define_roles!(Roles => [ ShellSurface, ShellSurfaceRole ] );
 
 #[derive(Default)]
 pub struct SurfaceData {
-    pub buffer: Option<(Vec<u8>, (u32, u32))>,
+    pub buffer: Option<Buffer>,
+    pub texture: Option<Texture2d>,
 }
 
-pub fn surface_implementation() -> SurfaceUserImplementation<SurfaceData, Roles, ()> {
+pub enum Buffer {
+    Egl { images: EGLImages },
+    Shm { data: Vec<u8>, size: (u32, u32) },
+}
+
+pub fn surface_implementation(
+) -> SurfaceUserImplementation<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>> {
     SurfaceUserImplementation {
-        commit: |_, _, surface, token| {
+        commit: |_, display, surface, token| {
             // we retrieve the contents of the associated buffer and copy it
             token.with_surface_data(surface, |attributes| {
                 match attributes.buffer.take() {
                     Some(Some((buffer, (_x, _y)))) => {
                         // we ignore hotspot coordinates in this simple example
-                        with_buffer_contents(&buffer, |slice, data| {
+                        match if let Some(display) = display.borrow().as_ref() {
+                            display.egl_buffer_contents(buffer)
+                        } else {
+                            Err(BufferAccessError::NotManaged(buffer))
+                        } {
+                            Ok(images) => {
+                                match images.format {
+                                    Format::RGB => {}
+                                    Format::RGBA => {}
+                                    _ => {
+                                        // we don't handle the more complex formats here.
+                                        attributes.user_data.buffer = None;
+                                        attributes.user_data.texture = None;
+                                        return;
+                                    }
+                                };
+                                attributes.user_data.texture = None;
+                                attributes.user_data.buffer = Some(Buffer::Egl { images });
+                            }
+                            Err(BufferAccessError::NotManaged(buffer)) => {
+                                shm_buffer_contents(&buffer, |slice, data| {
                                     let offset = data.offset as usize;
                                     let stride = data.stride as usize;
                                     let width = data.width as usize;
@@ -34,14 +64,18 @@ pub fn surface_implementation() -> SurfaceUserImplementation<SurfaceData, Roles,
                                         new_vec
                                             .extend(&slice[(offset + i * stride)..(offset + i * stride + width * 4)]);
                                     }
-                            attributes.user_data.buffer =
-                                Some((new_vec, (data.width as u32, data.height as u32)));
-                        }).unwrap();
+                                    attributes.user_data.texture = None;
+                                    attributes.user_data.buffer = Some(Buffer::Shm { data: new_vec, size: (data.width as u32, data.height as u32) });
+                                }).expect("Got EGL buffer with no set EGLDisplay. You need to unbind your EGLContexts before dropping them!");
                                 buffer.release();
                             }
+                            Err(err) => panic!("EGL error: {}", err),
+                        }
+                    }
                     Some(None) => {
                         // erase the contents
                         attributes.user_data.buffer = None;
+                        attributes.user_data.texture = None;
                     }
                     None => {}
                 }
@@ -54,11 +88,12 @@ pub fn surface_implementation() -> SurfaceUserImplementation<SurfaceData, Roles,
 }
 
 pub struct ShellIData<F> {
-    pub token: CompositorToken<SurfaceData, Roles, ()>,
-    pub window_map: Rc<RefCell<super::WindowMap<SurfaceData, Roles, (), (), F>>>,
+    pub token: CompositorToken<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>>,
+    pub window_map: Rc<RefCell<super::WindowMap<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>, (), F>>>,
 }
 
-pub fn shell_implementation<F>() -> ShellSurfaceUserImplementation<SurfaceData, Roles, (), ShellIData<F>, ()>
+pub fn shell_implementation<F>(
+) -> ShellSurfaceUserImplementation<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>, ShellIData<F>, ()>
 where
     F: Fn(&SurfaceAttributes<SurfaceData>) -> Option<(i32, i32)>,
 {
@@ -79,22 +114,18 @@ where
                 serial: 42,
             }
         },
-        new_popup: |_, _, _| {
-            PopupConfigure {
+        new_popup: |_, _, _| PopupConfigure {
             size: (10, 10),
             position: (10, 10),
             serial: 42,
-            }
         },
         move_: |_, _, _, _, _| {},
         resize: |_, _, _, _, _, _| {},
         grab: |_, _, _, _, _| {},
-        change_display_state: |_, _, _, _, _, _, _| {
-            ToplevelConfigure {
+        change_display_state: |_, _, _, _, _, _, _| ToplevelConfigure {
             size: None,
             states: vec![],
             serial: 42,
-            }
         },
         show_window_menu: |_, _, _, _, _, _, _| {},
     }
@@ -105,25 +136,29 @@ fn get_size(attrs: &SurfaceAttributes<SurfaceData>) -> Option<(i32, i32)> {
         .user_data
         .buffer
         .as_ref()
-        .map(|&(_, (w, h))| (w as i32, h as i32))
+        .map(|ref buffer| match **buffer {
+            Buffer::Shm { ref size, .. } => *size,
+            Buffer::Egl { ref images } => (images.width, images.height),
+        })
+        .map(|(x, y)| (x as i32, y as i32))
 }
 
 pub type MyWindowMap = WindowMap<
     SurfaceData,
     Roles,
-    (),
+    Rc<RefCell<Option<EGLDisplay>>>,
     (),
     fn(&SurfaceAttributes<SurfaceData>) -> Option<(i32, i32)>,
 >;
 
 pub fn init_shell(
-    evl: &mut EventLoop, log: ::slog::Logger)
-    -> (
-        CompositorToken<SurfaceData, Roles, ()>,
-        StateToken<ShellState<SurfaceData, Roles, (), ()>>,
+    evl: &mut EventLoop, log: ::slog::Logger, data: Rc<RefCell<Option<EGLDisplay>>>
+) -> (
+    CompositorToken<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>>,
+    StateToken<ShellState<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>, ()>>,
     Rc<RefCell<MyWindowMap>>,
 ) {
-    let (compositor_token, _, _) = compositor_init(evl, surface_implementation(), (), log.clone());
+    let (compositor_token, _, _) = compositor_init(evl, surface_implementation(), data, log.clone());
 
     let window_map = Rc::new(RefCell::new(WindowMap::<_, _, _, (), _>::new(
         compositor_token,

examples/helpers/window_map.rs

@@ -19,8 +19,9 @@ where
     SD: 'static,
 {
     // Find the topmost surface under this point if any and the location of this point in the surface
-    fn matching<F>(&self, point: (f64, f64), ctoken: CompositorToken<U, R, CID>, get_size: F)
-                   -> Option<(wl_surface::WlSurface, (f64, f64))>
+    fn matching<F>(
+        &self, point: (f64, f64), ctoken: CompositorToken<U, R, CID>, get_size: F
+    ) -> Option<(wl_surface::WlSurface, (f64, f64))>
     where
         F: Fn(&SurfaceAttributes<U>) -> Option<(i32, i32)>,
     {
@@ -33,7 +34,8 @@ where
             let _ = ctoken.with_surface_tree_downward(
                 wl_surface,
                 self.location,
-                |wl_surface, attributes, role, &(mut x, mut y)| if let Some((w, h)) = get_size(attributes) {
+                |wl_surface, attributes, role, &(mut x, mut y)| {
+                    if let Some((w, h)) = get_size(attributes) {
                         if let Ok(subdata) = Role::<SubsurfaceRole>::data(role) {
                             x += subdata.x;
                             y += subdata.y;
@@ -45,15 +47,16 @@ where
                             height: h,
                         };
                         if my_rect.contains((point.0 as i32, point.1 as i32)) {
-                        found = wl_surface.clone().map(|s| {
-                            (s, (point.0 - my_rect.x as f64, point.1 - my_rect.y as f64))
-                        });
+                            found = wl_surface
+                                .clone()
+                                .map(|s| (s, (point.0 - my_rect.x as f64, point.1 - my_rect.y as f64)));
                             TraversalAction::Break
                         } else {
                             TraversalAction::DoChildren((x, y))
                         }
                     } else {
                         TraversalAction::SkipChildren
+                    }
                 },
             );
         }
@@ -151,8 +154,9 @@ where
         None
     }
 
-    pub fn get_surface_and_bring_to_top(&mut self, point: (f64, f64))
-                                        -> Option<(wl_surface::WlSurface, (f64, f64))> {
+    pub fn get_surface_and_bring_to_top(
+        &mut self, point: (f64, f64)
+    ) -> Option<(wl_surface::WlSurface, (f64, f64))> {
         let mut found = None;
         for (i, w) in self.windows.iter().enumerate() {
             if let Some(surface) = w.matching(point, self.ctoken, &self.get_size) {

examples/udev.rs

@@ -1,14 +1,14 @@
 extern crate drm;
 #[macro_use]
 extern crate glium;
-extern crate rand;
-extern crate input as libinput;
 extern crate image;
-extern crate udev;
+extern crate input as libinput;
+extern crate rand;
 #[macro_use(define_roles)]
 extern crate smithay;
-extern crate xkbcommon;
+extern crate udev;
 extern crate wayland_server;
+extern crate xkbcommon;
 
 #[macro_use]
 extern crate slog;
@@ -21,41 +21,43 @@ mod helpers;
 
 use drm::control::{Device as ControlDevice, ResourceInfo};
 use drm::control::connector::{Info as ConnectorInfo, State as ConnectorState};
-use drm::control::encoder::Info as EncoderInfo;
 use drm::control::crtc;
+use drm::control::encoder::Info as EncoderInfo;
 use drm::result::Error as DrmError;
-use glium::Surface;
+use glium::{Blend, Surface};
+use helpers::{init_shell, Buffer, GliumDrawer, MyWindowMap, Roles, SurfaceData};
 use image::{ImageBuffer, Rgba};
-use libinput::{Libinput, Device as LibinputDevice, event};
+use libinput::{event, Device as LibinputDevice, Libinput};
 use libinput::event::keyboard::KeyboardEventTrait;
-use helpers::{init_shell, GliumDrawer, MyWindowMap, Roles, SurfaceData};
 use slog::{Drain, Logger};
-use smithay::backend::drm::{DrmBackend, DrmDevice, DrmHandler};
+use smithay::backend::drm::{DevPath, DrmBackend, DrmDevice, DrmHandler};
 use smithay::backend::graphics::GraphicsBackend;
 use smithay::backend::graphics::egl::EGLGraphicsBackend;
-use smithay::backend::input::{self, Event, InputBackend, InputHandler, KeyboardKeyEvent, PointerButtonEvent,
-                              PointerAxisEvent, KeyState};
-use smithay::backend::libinput::{LibinputInputBackend, libinput_bind, PointerAxisEvent as LibinputPointerAxisEvent, LibinputSessionInterface};
-use smithay::backend::udev::{UdevBackend, UdevHandler, udev_backend_bind};
+use smithay::backend::graphics::egl::wayland::{EGLDisplay, EGLWaylandExtensions, Format};
+use smithay::backend::input::{self, Event, InputBackend, InputHandler, KeyState, KeyboardKeyEvent,
+                              PointerAxisEvent, PointerButtonEvent};
+use smithay::backend::libinput::{libinput_bind, LibinputInputBackend, LibinputSessionInterface,
+                                 PointerAxisEvent as LibinputPointerAxisEvent};
 use smithay::backend::session::{Session, SessionNotifier};
 use smithay::backend::session::direct::{direct_session_bind, DirectSession};
+use smithay::backend::udev::{primary_gpu, udev_backend_bind, SessionFdDrmDevice, UdevBackend, UdevHandler};
 use smithay::wayland::compositor::{CompositorToken, SubsurfaceRole, TraversalAction};
 use smithay::wayland::compositor::roles::Role;
 use smithay::wayland::output::{Mode, Output, PhysicalProperties};
 use smithay::wayland::seat::{KeyboardHandle, PointerHandle, Seat};
-use smithay::wayland::shell::ShellState;
 use smithay::wayland::shm::init_shm_global;
 use std::cell::RefCell;
-use std::collections::HashSet;
+use std::collections::HashMap;
 use std::io::Error as IoError;
+use std::path::PathBuf;
+use std::process::Command;
 use std::rc::Rc;
 use std::sync::Arc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::time::Duration;
-use std::process::Command;
-use xkbcommon::xkb::keysyms as xkb;
-use wayland_server::{StateToken, StateProxy};
+use wayland_server::{Display, StateProxy, StateToken};
 use wayland_server::protocol::{wl_output, wl_pointer};
+use xkbcommon::xkb::keysyms as xkb;
 
 struct LibinputInputHandler {
     log: Logger,
@@ -91,7 +93,8 @@ impl InputHandler<LibinputInputBackend> for LibinputInputHandler {
         debug!(self.log, "key"; "keycode" => keycode, "state" => format!("{:?}", state));
 
         let serial = self.next_serial();
-        self.keyboard.input(keycode, state, serial, |modifiers, keysym| {
+        self.keyboard
+            .input(keycode, state, serial, |modifiers, keysym| {
                 if modifiers.ctrl && modifiers.alt && keysym == xkb::KEY_BackSpace {
                     self.running.store(false, Ordering::SeqCst);
                     false
@@ -109,7 +112,9 @@ impl InputHandler<LibinputInputBackend> for LibinputInputHandler {
         let mut location = self.pointer_location.borrow_mut();
         location.0 += x;
         location.1 += y;
-        let under = self.window_map.borrow().get_surface_under((location.0, location.1));
+        let under = self.window_map
+            .borrow()
+            .get_surface_under((location.0, location.1));
         self.pointer.motion(
             under.as_ref().map(|&(ref s, (x, y))| (s, x, y)),
             serial,
@@ -117,7 +122,10 @@ impl InputHandler<LibinputInputBackend> for LibinputInputHandler {
         );
     }
     fn on_pointer_move_absolute(&mut self, _: &input::Seat, evt: event::pointer::PointerMotionAbsoluteEvent) {
-        let (x, y) = (evt.absolute_x_transformed(self.screen_size.0), evt.absolute_y_transformed(self.screen_size.1));
+        let (x, y) = (
+            evt.absolute_x_transformed(self.screen_size.0),
+            evt.absolute_y_transformed(self.screen_size.1),
+        );
         *self.pointer_location.borrow_mut() = (x, y);
         let serial = self.next_serial();
         let under = self.window_map.borrow().get_surface_under((x, y));
@@ -172,21 +180,33 @@ impl InputHandler<LibinputInputBackend> for LibinputInputHandler {
 }
 
 fn main() {
+    let active_egl_context = Rc::new(RefCell::new(None));
+
     // A logger facility, here we use the terminal for this example
     let log = Logger::root(
-        slog_term::FullFormat::new(slog_term::PlainSyncDecorator::new(std::io::stdout())).build().fuse(),
+        slog_term::FullFormat::new(slog_term::PlainSyncDecorator::new(std::io::stdout()))
+            .build()
+            .fuse(),
         o!(),
     );
 
     // Initialize the wayland server
     let (mut display, mut event_loop) = wayland_server::create_display();
 
+    /*
+     * Add a listening socket
+     */
+    let name = display.add_socket_auto().unwrap().into_string().unwrap();
+    println!("Listening on socket: {}", name);
+    let display = Rc::new(display);
+
     /*
      * Initialize the compositor
      */
     init_shm_global(&mut event_loop, vec![], log.clone());
 
-    let (compositor_token, shell_state_token, window_map) = init_shell(&mut event_loop, log.clone());
+    let (compositor_token, _shell_state_token, window_map) =
+        init_shell(&mut event_loop, log.clone(), active_egl_context.clone());
 
     /*
      * Initialize session on the current tty
@@ -206,16 +226,28 @@ fn main() {
      * Initialize the udev backend
      */
     let context = udev::Context::new().unwrap();
+    let seat = session.seat();
+
+    let primary_gpu = primary_gpu(&context, &seat).unwrap_or_default();
+
     let bytes = include_bytes!("resources/cursor2.rgba");
-    let udev_token
-        = UdevBackend::new(&mut event_loop, &context, session.clone(), UdevHandlerImpl {
-            shell_state_token,
+    let udev_token = UdevBackend::new(
+        &mut event_loop,
+        &context,
+        session.clone(),
+        UdevHandlerImpl {
             compositor_token,
+            active_egl_context,
+            backends: HashMap::new(),
+            display: display.clone(),
+            primary_gpu,
             window_map: window_map.clone(),
             pointer_location: pointer_location.clone(),
             pointer_image: ImageBuffer::from_raw(64, 64, bytes.to_vec()).unwrap(),
             logger: log.clone(),
-        }, log.clone()).unwrap();
+        },
+        log.clone(),
+    ).unwrap();
 
     let udev_session_id = notifier.register(udev_token.clone());
 
@@ -266,8 +298,9 @@ fn main() {
     /*
      * Initialize libinput backend
      */
-    let seat = session.seat();
-    let mut libinput_context = Libinput::new_from_udev::<LibinputSessionInterface<Rc<RefCell<DirectSession>>>>(session.into(), &context);
+    let mut libinput_context = Libinput::new_from_udev::<
+        LibinputSessionInterface<Rc<RefCell<DirectSession>>>,
+    >(session.into(), &context);
     let libinput_session_id = notifier.register(libinput_context.clone());
     libinput_context.udev_assign_seat(&seat).unwrap();
     let mut libinput_backend = LibinputInputBackend::new(libinput_context, log.clone());
@@ -286,17 +319,14 @@ fn main() {
     let session_event_source = direct_session_bind(notifier, &mut event_loop, log.clone()).unwrap();
     let udev_event_source = udev_backend_bind(&mut event_loop, udev_token).unwrap();
 
-    /*
-     * Add a listening socket
-     */
-    let name = display.add_socket_auto().unwrap().into_string().unwrap();
-    println!("Listening on socket: {}", name);
-
     while running.load(Ordering::SeqCst) {
-        event_loop.dispatch(Some(16));
+        if let Err(_) = event_loop.dispatch(Some(16)) {
+            running.store(false, Ordering::SeqCst);
+        } else {
             display.flush_clients();
             window_map.borrow_mut().refresh();
         }
+    }
 
     println!("Bye Bye");
 
@@ -312,8 +342,11 @@ fn main() {
 }
 
 struct UdevHandlerImpl {
-    shell_state_token: StateToken<ShellState<SurfaceData, Roles, (), ()>>,
-    compositor_token: CompositorToken<SurfaceData, Roles, ()>,
+    compositor_token: CompositorToken<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>>,
+    active_egl_context: Rc<RefCell<Option<EGLDisplay>>>,
+    backends: HashMap<u64, Rc<RefCell<HashMap<crtc::Handle, GliumDrawer<DrmBackend<SessionFdDrmDevice>>>>>>,
+    display: Rc<Display>,
+    primary_gpu: Option<PathBuf>,
     window_map: Rc<RefCell<MyWindowMap>>,
     pointer_location: Rc<RefCell<(f64, f64)>>,
     pointer_image: ImageBuffer<Rgba<u8>, Vec<u8>>,
@@ -321,7 +354,9 @@ struct UdevHandlerImpl {
 }
 
 impl UdevHandlerImpl {
-    pub fn scan_connectors<'a, S: Into<StateProxy<'a>>>(&self, state: S, device: &mut DrmDevice<GliumDrawer<DrmBackend>>) {
+    pub fn scan_connectors(
+        &self, device: &mut DrmDevice<SessionFdDrmDevice>
+    ) -> HashMap<crtc::Handle, GliumDrawer<DrmBackend<SessionFdDrmDevice>>> {
         // Get a set of all modesetting resource handles (excluding planes):
         let res_handles = device.resource_handles().unwrap();
 
@@ -329,79 +364,97 @@ impl UdevHandlerImpl {
         let connector_infos: Vec<ConnectorInfo> = res_handles
             .connectors()
             .iter()
-            .map(|conn| {
-                ConnectorInfo::load_from_device(device, *conn).unwrap()
-            })
+            .map(|conn| ConnectorInfo::load_from_device(device, *conn).unwrap())
             .filter(|conn| conn.connection_state() == ConnectorState::Connected)
             .inspect(|conn| info!(self.logger, "Connected: {:?}", conn.connector_type()))
             .collect();
 
-        let mut used_crtcs: HashSet<crtc::Handle> = HashSet::new();
-
-        let mut state = state.into();
+        let mut backends = HashMap::new();
 
         // very naive way of finding good crtc/encoder/connector combinations. This problem is np-complete
         for connector_info in connector_infos {
-            let encoder_infos = connector_info.encoders().iter().flat_map(|encoder_handle| EncoderInfo::load_from_device(device, *encoder_handle)).collect::<Vec<EncoderInfo>>();
+            let encoder_infos = connector_info
+                .encoders()
+                .iter()
+                .flat_map(|encoder_handle| EncoderInfo::load_from_device(device, *encoder_handle))
+                .collect::<Vec<EncoderInfo>>();
             for encoder_info in encoder_infos {
                 for crtc in res_handles.filter_crtcs(encoder_info.possible_crtcs()) {
-                    if !used_crtcs.contains(&crtc) {
+                    if !backends.contains_key(&crtc) {
                         let mode = connector_info.modes()[0]; // Use first mode (usually highest resoltion, but in reality you should filter and sort and check and match with other connectors, if you use more then one.)
                                                               // create a backend
-                        let renderer_token = device.create_backend(&mut state, crtc, mode, vec![connector_info.handle()]).unwrap();
+                        let renderer = GliumDrawer::from(
+                            device
+                                .create_backend(crtc, mode, vec![connector_info.handle()])
+                                .unwrap(),
+                        );
 
                         // create cursor
-                        {
-                            let renderer = state.get_mut(renderer_token);
-                            renderer.set_cursor_representation(&self.pointer_image, (2, 2)).unwrap();
-                        }
+                        renderer
+                            .set_cursor_representation(&self.pointer_image, (2, 2))
+                            .unwrap();
 
                         // render first frame
                         {
-                            let renderer = state.get_mut(renderer_token);
                             let mut frame = renderer.draw();
                             frame.clear_color(0.8, 0.8, 0.9, 1.0);
                             frame.finish().unwrap();
                         }
 
-                        used_crtcs.insert(crtc);
+                        backends.insert(crtc, renderer);
                         break;
                     }
                 }
             }
         }
+
+        backends
     }
 }
 
-impl UdevHandler<GliumDrawer<DrmBackend>, DrmHandlerImpl> for UdevHandlerImpl {
-    fn device_added<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &mut DrmDevice<GliumDrawer<DrmBackend>>) -> Option<DrmHandlerImpl>
-    {
-        self.scan_connectors(state, device);
+impl UdevHandler<DrmHandlerImpl> for UdevHandlerImpl {
+    fn device_added<'a, S: Into<StateProxy<'a>>>(
+        &mut self, _state: S, device: &mut DrmDevice<SessionFdDrmDevice>
+    ) -> Option<DrmHandlerImpl> {
+        // init hardware acceleration on the primary gpu.
+        if device.dev_path().and_then(|path| path.canonicalize().ok()) == self.primary_gpu {
+            *self.active_egl_context.borrow_mut() = device.bind_wl_display(&*self.display).ok();
+        }
+
+        let backends = Rc::new(RefCell::new(self.scan_connectors(device)));
+        self.backends.insert(device.device_id(), backends.clone());
 
         Some(DrmHandlerImpl {
-            shell_state_token: self.shell_state_token.clone(),
             compositor_token: self.compositor_token.clone(),
+            backends,
             window_map: self.window_map.clone(),
             pointer_location: self.pointer_location.clone(),
             logger: self.logger.clone(),
         })
     }
 
-    fn device_changed<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &StateToken<DrmDevice<GliumDrawer<DrmBackend>>>) {
-        //quick and dirt, just re-init the device
+    fn device_changed<'a, S: Into<StateProxy<'a>>>(
+        &mut self, state: S, device: &StateToken<DrmDevice<SessionFdDrmDevice>>
+    ) {
+        //quick and dirt, just re-init all backends
         let mut state = state.into();
-        self.device_removed(&mut state, device);
-        state.with_value(device, |state, device| self.scan_connectors(state, device));
+        let backends = self.backends.get(&state.get(device).device_id()).unwrap();
+        *backends.borrow_mut() = self.scan_connectors(state.get_mut(device));
     }
 
-    fn device_removed<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &StateToken<DrmDevice<GliumDrawer<DrmBackend>>>) {
-        state.into().with_value(device, |state, device| {
-            let crtcs = device.current_backends().into_iter().map(|backend| state.get(backend).crtc()).collect::<Vec<crtc::Handle>>();
-            let mut state: StateProxy = state.into();
-            for crtc in crtcs {
-                device.destroy_backend(&mut state, &crtc);
+    fn device_removed<'a, S: Into<StateProxy<'a>>>(
+        &mut self, state: S, device: &StateToken<DrmDevice<SessionFdDrmDevice>>
+    ) {
+        let state = state.into();
+        let device = state.get(device);
+
+        // drop the backends on this side
+        self.backends.remove(&device.device_id());
+
+        // don't use hardware acceleration anymore, if this was the primary gpu
+        if device.dev_path().and_then(|path| path.canonicalize().ok()) == self.primary_gpu {
+            *self.active_egl_context.borrow_mut() = None;
         }
-        });
     }
 
     fn error<'a, S: Into<StateProxy<'a>>>(&mut self, _state: S, error: IoError) {
@@ -410,30 +463,30 @@ impl UdevHandler<GliumDrawer<DrmBackend>, DrmHandlerImpl> for UdevHandlerImpl {
 }
 
 pub struct DrmHandlerImpl {
-    shell_state_token: StateToken<ShellState<SurfaceData, Roles, (), ()>>,
-    compositor_token: CompositorToken<SurfaceData, Roles, ()>,
+    compositor_token: CompositorToken<SurfaceData, Roles, Rc<RefCell<Option<EGLDisplay>>>>,
+    backends: Rc<RefCell<HashMap<crtc::Handle, GliumDrawer<DrmBackend<SessionFdDrmDevice>>>>>,
     window_map: Rc<RefCell<MyWindowMap>>,
     pointer_location: Rc<RefCell<(f64, f64)>>,
     logger: ::slog::Logger,
 }
 
-impl DrmHandler<GliumDrawer<DrmBackend>> for DrmHandlerImpl {
-    fn ready<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, _device: &mut DrmDevice<GliumDrawer<DrmBackend>>,
-             backend: &StateToken<GliumDrawer<DrmBackend>>, _crtc: crtc::Handle, _frame: u32, _duration: Duration) {
-        let state = state.into();
-        let drawer = state.get(backend);
+impl DrmHandler<SessionFdDrmDevice> for DrmHandlerImpl {
+    fn ready(
+        &mut self, _device: &mut DrmDevice<SessionFdDrmDevice>, crtc: crtc::Handle, _frame: u32,
+        _duration: Duration,
+    ) {
+        if let Some(drawer) = self.backends.borrow().get(&crtc) {
             {
                 let (x, y) = *self.pointer_location.borrow();
-            let _ = (**drawer).set_cursor_position(x.trunc().abs() as u32, y.trunc().abs() as u32);
+                let _ = drawer.set_cursor_position(x.trunc().abs() as u32, y.trunc().abs() as u32);
             }
             let mut frame = drawer.draw();
             frame.clear_color(0.8, 0.8, 0.9, 1.0);
             // redraw the frame, in a simple but inneficient way
             {
                 let screen_dimensions = drawer.get_framebuffer_dimensions();
-            self.window_map
-                .borrow()
-                .with_windows_from_bottom_to_top(|toplevel_surface, initial_place| {
+                self.window_map.borrow().with_windows_from_bottom_to_top(
+                    |toplevel_surface, initial_place| {
                         if let Some(wl_surface) = toplevel_surface.get_surface() {
                             // this surface is a root of a subsurface tree that needs to be drawn
                             self.compositor_token
@@ -441,18 +494,56 @@ impl DrmHandler<GliumDrawer<DrmBackend>> for DrmHandlerImpl {
                                     wl_surface,
                                     initial_place,
                                     |_surface, attributes, role, &(mut x, mut y)| {
-                                    if let Some((ref contents, (w, h))) = attributes.user_data.buffer {
                                         // there is actually something to draw !
+                                        if attributes.user_data.texture.is_none() {
+                                            let mut remove = false;
+                                            match attributes.user_data.buffer {
+                                                Some(Buffer::Egl { ref images }) => {
+                                                    match images.format {
+                                                        Format::RGB | Format::RGBA => {
+                                                            attributes.user_data.texture =
+                                                                drawer.texture_from_egl(&images);
+                                                        }
+                                                        _ => {
+                                                            // we don't handle the more complex formats here.
+                                                            attributes.user_data.texture = None;
+                                                            remove = true;
+                                                        }
+                                                    };
+                                                }
+                                                Some(Buffer::Shm { ref data, ref size }) => {
+                                                    attributes.user_data.texture =
+                                                        Some(drawer.texture_from_mem(data, *size));
+                                                }
+                                                _ => {}
+                                            }
+                                            if remove {
+                                                attributes.user_data.buffer = None;
+                                            }
+                                        }
+
+                                        if let Some(ref texture) = attributes.user_data.texture {
                                             if let Ok(subdata) = Role::<SubsurfaceRole>::data(role) {
                                                 x += subdata.x;
                                                 y += subdata.y;
                                             }
-                                        drawer.render(
+                                            info!(self.logger, "Render window");
+                                            drawer.render_texture(
                                                 &mut frame,
-                                            contents,
-                                            (w, h),
+                                                texture,
+                                                match *attributes.user_data.buffer.as_ref().unwrap() {
+                                                    Buffer::Egl { ref images } => images.y_inverted,
+                                                    Buffer::Shm { .. } => false,
+                                                },
+                                                match *attributes.user_data.buffer.as_ref().unwrap() {
+                                                    Buffer::Egl { ref images } => {
+                                                        (images.width, images.height)
+                                                    }
+                                                    Buffer::Shm { ref size, .. } => *size,
+                                                },
                                                 (x, y),
                                                 screen_dimensions,
+                                                Blend::alpha_blending(),
                                             );
                                             TraversalAction::DoChildren((x, y))
                                         } else {
@@ -463,15 +554,16 @@ impl DrmHandler<GliumDrawer<DrmBackend>> for DrmHandlerImpl {
                                 )
                                 .unwrap();
                         }
-                });
+                    },
+                );
             }
             if let Err(err) = frame.finish() {
                 error!(self.logger, "Error during rendering: {:?}", err);
             }
         }
+    }
 
-    fn error<'a, S: Into<StateProxy<'a>>>(&mut self, _state: S, _device: &mut DrmDevice<GliumDrawer<DrmBackend>>,
-             error: DrmError) {
+    fn error(&mut self, _device: &mut DrmDevice<SessionFdDrmDevice>, error: DrmError) {
         error!(self.logger, "{:?}", error);
     }
 }

examples/winit.rs

@@ -12,9 +12,10 @@ extern crate wayland_server;
 mod helpers;
 
 use glium::Surface;
-use helpers::{init_shell, GliumDrawer, MyWindowMap};
+use helpers::{init_shell, Buffer, GliumDrawer, MyWindowMap};
 use slog::{Drain, Logger};
 use smithay::backend::graphics::egl::EGLGraphicsBackend;
+use smithay::backend::graphics::egl::wayland::{EGLWaylandExtensions, Format};
 use smithay::backend::input::{self, Event, InputBackend, InputHandler, KeyboardKeyEvent, PointerAxisEvent,
                               PointerButtonEvent, PointerMotionAbsoluteEvent};
 use smithay::backend::winit;
@@ -136,13 +137,26 @@ fn main() {
 
     let (mut display, mut event_loop) = wayland_server::create_display();
 
+    let egl_display = Rc::new(RefCell::new(
+        if let Ok(egl_display) = renderer.bind_wl_display(&display) {
+            info!(log, "EGL hardware-acceleration enabled");
+            Some(egl_display)
+        } else {
+            None
+        },
+    ));
+
+    let (w, h) = renderer.get_framebuffer_dimensions();
+    let drawer = GliumDrawer::from(renderer);
+
     /*
      * Initialize the globals
      */
 
     init_shm_global(&mut event_loop, vec![], log.clone());
 
-    let (compositor_token, _shell_state_token, window_map) = init_shell(&mut event_loop, log.clone());
+    let (compositor_token, _shell_state_token, window_map) =
+        init_shell(&mut event_loop, log.clone(), egl_display);
 
     let (seat_token, _) = Seat::new(&mut event_loop, "winit".into(), log.clone());
 
@@ -166,7 +180,6 @@ fn main() {
         log.clone(),
     );
 
-    let (w, h) = renderer.get_framebuffer_dimensions();
     event_loop
         .state()
         .get_mut(&output_token)
@@ -188,11 +201,6 @@ fn main() {
             refresh: 60_000,
         });
 
-    /*
-     * Initialize glium
-     */
-    let drawer = GliumDrawer::from(renderer);
-
     input.set_handler(WinitInputHandler {
         log: log.clone(),
         pointer,
@@ -212,7 +220,7 @@ fn main() {
         input.dispatch_new_events().unwrap();
 
         let mut frame = drawer.draw();
-        frame.clear(None, Some((0.8, 0.8, 0.9, 1.0)), false, None, None);
+        frame.clear(None, Some((0.8, 0.8, 0.9, 1.0)), false, Some(1.0), None);
         // redraw the frame, in a simple but inneficient way
         {
             let screen_dimensions = drawer.get_framebuffer_dimensions();
@@ -226,18 +234,65 @@ fn main() {
                                 wl_surface,
                                 initial_place,
                                 |_surface, attributes, role, &(mut x, mut y)| {
-                                    if let Some((ref contents, (w, h))) = attributes.user_data.buffer {
                                     // there is actually something to draw !
+                                    if attributes.user_data.texture.is_none() {
+                                        let mut remove = false;
+                                        match attributes.user_data.buffer {
+                                            Some(Buffer::Egl { ref images }) => {
+                                                match images.format {
+                                                    Format::RGB | Format::RGBA => {
+                                                        attributes.user_data.texture =
+                                                            drawer.texture_from_egl(&images);
+                                                    }
+                                                    _ => {
+                                                        // we don't handle the more complex formats here.
+                                                        attributes.user_data.texture = None;
+                                                        remove = true;
+                                                    }
+                                                };
+                                            }
+                                            Some(Buffer::Shm { ref data, ref size }) => {
+                                                attributes.user_data.texture =
+                                                    Some(drawer.texture_from_mem(data, *size));
+                                            }
+                                            _ => {}
+                                        }
+                                        if remove {
+                                            attributes.user_data.buffer = None;
+                                        }
+                                    }
+
+                                    if let Some(ref texture) = attributes.user_data.texture {
                                         if let Ok(subdata) = Role::<SubsurfaceRole>::data(role) {
                                             x += subdata.x;
                                             y += subdata.y;
                                         }
-                                        drawer.render(
+                                        drawer.render_texture(
                                             &mut frame,
-                                            contents,
-                                            (w, h),
+                                            texture,
+                                            match *attributes.user_data.buffer.as_ref().unwrap() {
+                                                Buffer::Egl { ref images } => images.y_inverted,
+                                                Buffer::Shm { .. } => false,
+                                            },
+                                            match *attributes.user_data.buffer.as_ref().unwrap() {
+                                                Buffer::Egl { ref images } => (images.width, images.height),
+                                                Buffer::Shm { ref size, .. } => *size,
+                                            },
                                             (x, y),
                                             screen_dimensions,
+                                            glium::Blend {
+                                                color: glium::BlendingFunction::Addition {
+                                                    source: glium::LinearBlendingFactor::One,
+                                                    destination:
+                                                        glium::LinearBlendingFactor::OneMinusSourceAlpha,
+                                                },
+                                                alpha: glium::BlendingFunction::Addition {
+                                                    source: glium::LinearBlendingFactor::One,
+                                                    destination:
+                                                        glium::LinearBlendingFactor::OneMinusSourceAlpha,
+                                                },
+                                                ..Default::default()
+                                            },
                                         );
                                         TraversalAction::DoChildren((x, y))
                                     } else {

src/backend/drm/backend.rs

@@ -1,129 +1,65 @@
-use super::devices;
+use super::DevPath;
 use super::error::*;
 use backend::graphics::GraphicsBackend;
-use backend::graphics::egl::{EGLGraphicsBackend, EGLSurface, PixelFormat, SwapBuffersError};
+use backend::graphics::egl::{EGLContext, EGLGraphicsBackend, EGLSurface, PixelFormat, SwapBuffersError};
+use backend::graphics::egl::error::Result as EGLResult;
+use backend::graphics::egl::native::{Gbm, GbmSurfaceArguments};
+use backend::graphics::egl::wayland::{EGLDisplay, EGLWaylandExtensions};
 use drm::control::{Device, ResourceInfo};
 use drm::control::{connector, crtc, encoder, framebuffer, Mode};
-use gbm::{BufferObject, BufferObjectFlags, Format as GbmFormat, Surface as GbmSurface, SurfaceBufferHandle};
+use gbm::{BufferObject, BufferObjectFlags, Device as GbmDevice, Format as GbmFormat, Surface as GbmSurface,
+          SurfaceBufferHandle};
 use image::{ImageBuffer, Rgba};
 use nix::libc::c_void;
 use std::cell::Cell;
-use std::rc::Rc;
-
-/*
-    Dependency graph
-    - drm
-        - gbm
-            - context
-            - gbm_surface
-                - egl_surface
-                - gbm_buffers
-            - cursor
-*/
-
-pub(crate) struct GbmTypes<'dev, 'context> {
-    cursor: Cell<BufferObject<'dev, ()>>,
-    surface: Surface<'context>,
-}
-
-pub(crate) struct EGL<'gbm, 'context> {
-    surface: EGLSurface<'context, 'gbm, GbmSurface<'context, framebuffer::Info>>,
-    buffers: GbmBuffers<'gbm>,
-}
-
-pub(crate) struct GbmBuffers<'gbm> {
-    front_buffer: Cell<SurfaceBufferHandle<'gbm, framebuffer::Info>>,
-    next_buffer: Cell<Option<SurfaceBufferHandle<'gbm, framebuffer::Info>>>,
-}
-
-rental! {
-    mod graphics {
-        use drm::control::framebuffer;
-        use gbm::Surface as GbmSurface;
-        use std::rc::Rc;
-        use super::devices::{Context, Context_Borrow};
-        use super::GbmTypes;
-
-        #[rental]
-        pub(crate) struct Surface<'context> {
-            gbm: Box<GbmSurface<'context, framebuffer::Info>>,
-            egl: super::EGL<'gbm, 'context>,
-        }
-
-        #[rental]
-        pub(crate) struct Graphics {
-            #[subrental(arity = 3)]
-            context: Rc<Context>,
-            gbm: GbmTypes<'context_1, 'context_2>,
-        }
-    }
-}
-use self::graphics::{Graphics, Surface};
+use std::rc::{Rc, Weak};
+use wayland_server::Display;
 
 /// Backend based on a `DrmDevice` and a given crtc
-pub struct DrmBackend {
-    graphics: Graphics,
-    crtc: crtc::Handle,
+pub struct DrmBackend<A: Device + 'static> {
+    backend: Rc<DrmBackendInternal<A>>,
+    surface: EGLSurface<GbmSurface<framebuffer::Info>>,
     mode: Mode,
     connectors: Vec<connector::Handle>,
+}
+
+pub(crate) struct DrmBackendInternal<A: Device + 'static> {
+    context: Rc<EGLContext<Gbm<framebuffer::Info>, GbmDevice<A>>>,
+    cursor: Cell<BufferObject<()>>,
+    current_frame_buffer: Cell<framebuffer::Info>,
+    front_buffer: Cell<SurfaceBufferHandle<framebuffer::Info>>,
+    next_buffer: Cell<Option<SurfaceBufferHandle<framebuffer::Info>>>,
+    crtc: crtc::Handle,
     logger: ::slog::Logger,
 }
 
-impl DrmBackend {
+impl<A: Device + 'static> DrmBackend<A> {
     pub(crate) fn new(
-        context: Rc<devices::Context>, crtc: crtc::Handle, mode: Mode, connectors: Vec<connector::Handle>,
-        logger: ::slog::Logger,
-    ) -> Result<DrmBackend> {
+        context: Rc<EGLContext<Gbm<framebuffer::Info>, GbmDevice<A>>>, crtc: crtc::Handle, mode: Mode,
+        connectors: Vec<connector::Handle>, log: ::slog::Logger,
+    ) -> Result<Self> {
         // logger already initialized by the DrmDevice
-        let log = ::slog_or_stdlog(logger);
         info!(log, "Initializing DrmBackend");
 
         let (w, h) = mode.size();
 
-        Ok(DrmBackend {
-            graphics: Graphics::try_new(context, |context| {
-                Ok(GbmTypes {
-                    cursor: {
-                        // Create an unused cursor buffer (we don't want an Option here)
-                        Cell::new(context
-                            .devices
-                            .gbm
-                            .create_buffer_object(
-                                1,
-                                1,
-                                GbmFormat::ARGB8888,
-                                BufferObjectFlags::CURSOR | BufferObjectFlags::WRITE,
-                            )
-                            .chain_err(|| ErrorKind::GbmInitFailed)?)
-                    },
-                    surface: Surface::try_new(
-                        {
-                            debug!(log, "Creating GbmSurface");
-                            // create a gbm surface
-                            Box::new(context
-                                .devices
-                                .gbm
-                                .create_surface(
-                                    w as u32,
-                                    h as u32,
-                                    GbmFormat::XRGB8888,
-                                    BufferObjectFlags::SCANOUT | BufferObjectFlags::RENDERING,
-                                )
-                                .chain_err(|| ErrorKind::GbmInitFailed)?)
-                        },
-                        |surface| {
-                            // create an egl surface from the gbm one
-                            debug!(log, "Creating EGLSurface");
-                            let egl_surface = context.egl.create_surface(surface)?;
+        debug!(log, "Creating Surface");
+        let surface = context
+            .create_surface(GbmSurfaceArguments {
+                size: (w as u32, h as u32),
+                format: GbmFormat::XRGB8888,
+                flags: BufferObjectFlags::SCANOUT | BufferObjectFlags::RENDERING,
+            })
+            .chain_err(|| ErrorKind::GbmInitFailed)?;
 
         // make it active for the first `crtc::set`
         // (which is needed before the first page_flip)
         unsafe {
-                                egl_surface
+            surface
                 .make_current()
                 .chain_err(|| ErrorKind::FailedToSwap)?
         };
-                            egl_surface
+        surface
             .swap_buffers()
             .chain_err(|| ErrorKind::FailedToSwap)?;
 
@@ -132,54 +68,61 @@ impl DrmBackend {
         let mut front_bo = surface
             .lock_front_buffer()
             .chain_err(|| ErrorKind::FailedToSwap)?;
+
         debug!(log, "FrontBuffer color format: {:?}", front_bo.format());
-                            // we need a framebuffer per front buffer
-                            let fb = framebuffer::create(context.devices.drm, &*front_bo)
-                                .chain_err(|| ErrorKind::DrmDev(format!("{:?}", context.devices.drm)))?;
+
+        // we need a framebuffer for the front buffer
+        let fb = framebuffer::create(&*context, &*front_bo).chain_err(|| {
+            ErrorKind::DrmDev(format!(
+                "Error creating framebuffer on {:?}",
+                context.dev_path()
+            ))
+        })?;
 
         debug!(log, "Initialize screen");
         crtc::set(
-                                context.devices.drm,
+            &*context,
             crtc,
             fb.handle(),
             &connectors,
             (0, 0),
             Some(mode),
-                            ).chain_err(|| ErrorKind::DrmDev(format!("{:?}", context.devices.drm)))?;
-                            front_bo.set_userdata(fb);
+        ).chain_err(|| {
+            ErrorKind::DrmDev(format!(
+                "Error setting crtc {:?} on {:?}",
+                crtc,
+                context.dev_path()
+            ))
+        })?;
+        front_bo.set_userdata(fb).unwrap();
 
-                            Ok(EGL {
-                                surface: egl_surface,
-                                buffers: GbmBuffers {
+        let cursor = Cell::new(context
+            .create_buffer_object(
+                1,
+                1,
+                GbmFormat::ARGB8888,
+                BufferObjectFlags::CURSOR | BufferObjectFlags::WRITE,
+            )
+            .chain_err(|| ErrorKind::GbmInitFailed)?);
+
+        Ok(DrmBackend {
+            backend: Rc::new(DrmBackendInternal {
+                context,
+                cursor,
+                current_frame_buffer: Cell::new(fb),
                 front_buffer: Cell::new(front_bo),
                 next_buffer: Cell::new(None),
-                                },
-                            })
-                        },
-                    ).map_err(Error::from)?,
-                })
-            })?,
                 crtc,
+                logger: log,
+            }),
+            surface,
             mode,
             connectors,
-            logger: log.clone(),
         })
     }
 
-    pub(crate) fn unlock_buffer(&self) {
-        // after the page swap is finished we need to release the rendered buffer.
-        // this is called from the PageFlipHandler
-        self.graphics.rent(|gbm| {
-            gbm.surface.rent(|egl| {
-                let next_bo = egl.buffers.next_buffer.replace(None);
-
-                if let Some(next_buffer) = next_bo {
-                    trace!(self.logger, "Releasing old front buffer");
-                    egl.buffers.front_buffer.set(next_buffer);
-                    // drop and release the old buffer
-                }
-            })
-        });
+    pub(crate) fn weak(&self) -> Weak<DrmBackendInternal<A>> {
+        Rc::downgrade(&self.backend)
     }
 
     /// Add a connector to backend
@@ -188,8 +131,12 @@ impl DrmBackend {
     ///
     /// Errors if the new connector does not support the currently set `Mode`
     pub fn add_connector(&mut self, connector: connector::Handle) -> Result<()> {
-        let info = connector::Info::load_from_device(self.graphics.head().head().head(), connector)
-            .chain_err(|| ErrorKind::DrmDev(format!("{:?}", self.graphics.head().head().head())))?;
+        let info = connector::Info::load_from_device(&*self.backend.context, connector).chain_err(|| {
+            ErrorKind::DrmDev(format!(
+                "Error loading connector info on {:?}",
+                self.backend.context.dev_path()
+            ))
+        })?;
 
         // check if the connector can handle the current mode
         if info.modes().contains(&self.mode) {
@@ -197,31 +144,35 @@ impl DrmBackend {
             let encoders = info.encoders()
                 .iter()
                 .map(|encoder| {
-                    encoder::Info::load_from_device(self.graphics.head().head().head(), *encoder)
-                        .chain_err(|| ErrorKind::DrmDev(format!("{:?}", self.graphics.head().head().head())))
+                    encoder::Info::load_from_device(&*self.backend.context, *encoder).chain_err(|| {
+                        ErrorKind::DrmDev(format!(
+                            "Error loading encoder info on {:?}",
+                            self.backend.context.dev_path()
+                        ))
+                    })
                 })
                 .collect::<Result<Vec<encoder::Info>>>()?;
 
             // and if any encoder supports the selected crtc
-            let resource_handles = self.graphics
-                .head()
-                .head()
-                .head()
-                .resource_handles()
-                .chain_err(|| ErrorKind::DrmDev(format!("{:?}", self.graphics.head().head().head())))?;
+            let resource_handles = self.backend.context.resource_handles().chain_err(|| {
+                ErrorKind::DrmDev(format!(
+                    "Error loading resources on {:?}",
+                    self.backend.context.dev_path()
+                ))
+            })?;
             if !encoders
                 .iter()
                 .map(|encoder| encoder.possible_crtcs())
                 .all(|crtc_list| {
                     resource_handles
                         .filter_crtcs(crtc_list)
-                        .contains(&self.crtc)
+                        .contains(&self.backend.crtc)
                 }) {
-                bail!(ErrorKind::NoSuitableEncoder(info, self.crtc));
+                bail!(ErrorKind::NoSuitableEncoder(info, self.backend.crtc));
             }
 
             info!(
-                self.logger,
+                self.backend.logger,
                 "Adding new connector: {:?}",
                 info.connector_type()
             );
@@ -239,14 +190,14 @@ impl DrmBackend {
 
     /// Removes a currently set connector
     pub fn remove_connector(&mut self, connector: connector::Handle) {
-        if let Ok(info) = connector::Info::load_from_device(self.graphics.head().head().head(), connector) {
+        if let Ok(info) = connector::Info::load_from_device(&*self.backend.context, connector) {
             info!(
-                self.logger,
+                self.backend.logger,
                 "Removing connector: {:?}",
                 info.connector_type()
             );
         } else {
-            info!(self.logger, "Removing unknown connector");
+            info!(self.backend.logger, "Removing unknown connector");
         }
 
         self.connectors.retain(|x| *x != connector);
@@ -262,8 +213,13 @@ impl DrmBackend {
     pub fn use_mode(&mut self, mode: Mode) -> Result<()> {
         // check the connectors
         for connector in &self.connectors {
-            if !connector::Info::load_from_device(self.graphics.head().head().head(), *connector)
-                .chain_err(|| ErrorKind::DrmDev(format!("{:?}", self.graphics.head().head().head())))?
+            if !connector::Info::load_from_device(&*self.backend.context, *connector)
+                .chain_err(|| {
+                    ErrorKind::DrmDev(format!(
+                        "Error loading connector info on {:?}",
+                        self.backend.context.dev_path()
+                    ))
+                })?
                 .modes()
                 .contains(&mode)
             {
@@ -271,160 +227,198 @@ impl DrmBackend {
             }
         }
 
-        // borrow & clone stuff because rust cannot figure out the upcoming
-        // closure otherwise.
-        let crtc = self.crtc;
-        let connectors_ref = &self.connectors;
-        let logger_ref = &self.logger;
-
+        info!(self.backend.logger, "Setting new mode: {:?}", mode.name());
         let (w, h) = mode.size();
 
-        self.graphics.rent_all_mut(|graphics| -> Result<()> {
         // Recreate the surface and the related resources to match the new
         // resolution.
         debug!(
-                logger_ref,
+            self.backend.logger,
             "Reinitializing surface for new mode: {}:{}", w, h
         );
-            graphics.gbm.surface = Surface::try_new(
-                {
-                    // create a new gbm surface
-                    debug!(logger_ref, "Creating GbmSurface");
-                    Box::new(graphics
+        let surface = self.backend
             .context
-                        .devices
-                        .gbm
-                        .create_surface(
-                            w as u32,
-                            h as u32,
-                            GbmFormat::XRGB8888,
-                            BufferObjectFlags::SCANOUT | BufferObjectFlags::RENDERING,
-                        )
-                        .chain_err(|| ErrorKind::GbmInitFailed)?)
-                },
-                |surface| {
-                    // create an egl surface from the gbm one
-                    debug!(logger_ref, "Creating EGLSurface");
-                    let egl_surface = graphics.context.egl.create_surface(surface)?;
+            .create_surface(GbmSurfaceArguments {
+                size: (w as u32, h as u32),
+                format: GbmFormat::XRGB8888,
+                flags: BufferObjectFlags::SCANOUT | BufferObjectFlags::RENDERING,
+            })
+            .chain_err(|| ErrorKind::GbmInitFailed)?;
 
         // make it active for the first `crtc::set`
         // (which is needed before the first page_flip)
         unsafe {
-                        egl_surface
+            surface
                 .make_current()
                 .chain_err(|| ErrorKind::FailedToSwap)?
         };
-                    egl_surface
+        surface
             .swap_buffers()
             .chain_err(|| ErrorKind::FailedToSwap)?;
 
+        // Clean up next_buffer
+        {
+            if let Some(mut old_bo) = self.backend.next_buffer.take() {
+                if let Ok(Some(fb)) = old_bo.take_userdata() {
+                    if let Err(err) = framebuffer::destroy(&*self.backend.context, fb.handle()) {
+                        warn!(
+                            self.backend.logger,
+                            "Error releasing old back_buffer framebuffer: {:?}", err
+                        );
+                    }
+                }
+            }
+        }
+
+        // Cleanup front_buffer and init the first screen on the new front_buffer
+        // (must be done before calling page_flip for the first time)
+        let mut old_front_bo = self.backend.front_buffer.replace({
             let mut front_bo = surface
                 .lock_front_buffer()
                 .chain_err(|| ErrorKind::FailedToSwap)?;
+
             debug!(
-                        logger_ref,
+                self.backend.logger,
                 "FrontBuffer color format: {:?}",
                 front_bo.format()
             );
-                    // we need a framebuffer per front_buffer
-                    let fb = framebuffer::create(graphics.context.devices.drm, &*front_bo)
-                        .chain_err(|| ErrorKind::DrmDev(format!("{:?}", graphics.context.devices.drm)))?;
 
-                    debug!(logger_ref, "Initialize screen");
+            // we also need a new framebuffer for the front buffer
+            let dev_path = self.backend.context.dev_path();
+            let fb = framebuffer::create(&*self.backend.context, &*front_bo)
+                .chain_err(|| ErrorKind::DrmDev(format!("Error creating framebuffer on {:?}", dev_path)))?;
+
+            front_bo.set_userdata(fb).unwrap();
+
+            debug!(self.backend.logger, "Setting screen");
             crtc::set(
-                        graphics.context.devices.drm,
-                        crtc,
+                &*self.backend.context,
+                self.backend.crtc,
                 fb.handle(),
-                        connectors_ref,
+                &self.connectors,
                 (0, 0),
                 Some(mode),
-                    ).chain_err(|| ErrorKind::DrmDev(format!("{:?}", graphics.context.devices.drm)))?;
-                    front_bo.set_userdata(fb);
-
-                    Ok(EGL {
-                        surface: egl_surface,
-                        buffers: GbmBuffers {
-                            front_buffer: Cell::new(front_bo),
-                            next_buffer: Cell::new(None),
-                        },
-                    })
-                },
-            )?;
-
-            Ok(())
+            ).chain_err(|| {
+                ErrorKind::DrmDev(format!(
+                    "Error setting crtc {:?} on {:?}",
+                    self.backend.crtc,
+                    self.backend.context.dev_path()
+                ))
             })?;
 
-        info!(self.logger, "Setting new mode: {:?}", mode.name());
+            front_bo
+        });
+        if let Ok(Some(fb)) = old_front_bo.take_userdata() {
+            if let Err(err) = framebuffer::destroy(&*self.backend.context, fb.handle()) {
+                warn!(
+                    self.backend.logger,
+                    "Error releasing old front_buffer framebuffer: {:?}", err
+                );
+            }
+        }
+
+        // Drop the old surface after cleanup
+        self.surface = surface;
         self.mode = mode;
         Ok(())
     }
 
     /// Returns the crtc id used by this backend
     pub fn crtc(&self) -> crtc::Handle {
-        self.crtc
+        self.backend.crtc
     }
 }
 
-impl Drop for DrmBackend {
+impl<A: Device + 'static> DrmBackendInternal<A> {
+    pub(crate) fn unlock_buffer(&self) {
+        // after the page swap is finished we need to release the rendered buffer.
+        // this is called from the PageFlipHandler
+        if let Some(next_buffer) = self.next_buffer.replace(None) {
+            trace!(self.logger, "Releasing old front buffer");
+            self.front_buffer.set(next_buffer);
+            // drop and release the old buffer
+        }
+    }
+
+    pub(crate) fn page_flip(
+        &self, fb: Option<&framebuffer::Info>
+    ) -> ::std::result::Result<(), SwapBuffersError> {
+        trace!(self.logger, "Queueing Page flip");
+
+        let fb = *fb.unwrap_or(&self.current_frame_buffer.get());
+
+        // and flip
+        crtc::page_flip(
+            &*self.context,
+            self.crtc,
+            fb.handle(),
+            &[crtc::PageFlipFlags::PageFlipEvent],
+        ).map_err(|_| SwapBuffersError::ContextLost)?;
+
+        self.current_frame_buffer.set(fb);
+
+        Ok(())
+    }
+}
+
+impl<A: Device + 'static> Drop for DrmBackend<A> {
     fn drop(&mut self) {
         // Drop framebuffers attached to the userdata of the gbm surface buffers.
         // (They don't implement drop, as they need the device)
-        let crtc = self.crtc;
-        self.graphics.rent_all_mut(|graphics| {
-            if let Some(fb) = graphics.gbm.surface.rent(|egl| {
-                if let Some(mut next) = egl.buffers.next_buffer.take() {
+        if let Ok(Some(fb)) = {
+            if let Some(mut next) = self.backend.next_buffer.take() {
                 next.take_userdata()
-                } else if let Ok(mut next) = graphics.gbm.surface.head().lock_front_buffer() {
+            } else if let Ok(mut next) = self.surface.lock_front_buffer() {
                 next.take_userdata()
             } else {
-                    None
+                Ok(None)
             }
-            }) {
+        } {
             // ignore failure at this point
-                let _ = framebuffer::destroy(&*graphics.context.devices.drm, fb.handle());
+            let _ = framebuffer::destroy(&*self.backend.context, fb.handle());
         }
-
-            if let Some(fb) = graphics.gbm.surface.rent_mut(|egl| {
-                let first = egl.buffers.front_buffer.get_mut();
-                first.take_userdata()
-            }) {
-                // ignore failure at this point
-                let _ = framebuffer::destroy(&*graphics.context.devices.drm, fb.handle());
-            }
-
-            // ignore failure at this point
-            let _ = crtc::clear_cursor(&*graphics.context.devices.drm, crtc);
-        })
     }
 }
 
-impl GraphicsBackend for DrmBackend {
+impl<A: Device + 'static> Drop for DrmBackendInternal<A> {
+    fn drop(&mut self) {
+        if let Ok(Some(fb)) = self.front_buffer.get_mut().take_userdata() {
+            // ignore failure at this point
+            let _ = framebuffer::destroy(&*self.context, fb.handle());
+        }
+
+        // ignore failure at this point
+        let _ = crtc::clear_cursor(&*self.context, self.crtc);
+    }
+}
+
+impl<A: Device + 'static> GraphicsBackend for DrmBackend<A> {
     type CursorFormat = ImageBuffer<Rgba<u8>, Vec<u8>>;
     type Error = Error;
 
     fn set_cursor_position(&self, x: u32, y: u32) -> Result<()> {
-        trace!(self.logger, "Move the cursor to {},{}", x, y);
+        trace!(self.backend.logger, "Move the cursor to {},{}", x, y);
         crtc::move_cursor(
-            self.graphics.head().head().head(),
-            self.crtc,
+            &*self.backend.context,
+            self.backend.crtc,
             (x as i32, y as i32),
-        ).chain_err(|| ErrorKind::DrmDev(format!("{:?}", self.graphics.head().head().head())))
+        ).chain_err(|| {
+            ErrorKind::DrmDev(format!(
+                "Error moving cursor on {:?}",
+                self.backend.context.dev_path()
+            ))
+        })
     }
 
     fn set_cursor_representation(
         &self, buffer: &ImageBuffer<Rgba<u8>, Vec<u8>>, hotspot: (u32, u32)
     ) -> Result<()> {
         let (w, h) = buffer.dimensions();
+        debug!(self.backend.logger, "Importing cursor");
 
-        debug!(self.logger, "Importing cursor");
-
-        self.graphics.rent_all(|graphics| -> Result<()> {
-            graphics.gbm.cursor.set({
         // import the cursor into a buffer we can render
-                let mut cursor = graphics
+        let mut cursor = self.backend
             .context
-                    .devices
-                    .gbm
             .create_buffer_object(
                 w,
                 h,
@@ -434,88 +428,81 @@ impl GraphicsBackend for DrmBackend {
             .chain_err(|| ErrorKind::GbmInitFailed)?;
         cursor
             .write(&**buffer)
+            .chain_err(|| ErrorKind::GbmInitFailed)?
             .chain_err(|| ErrorKind::GbmInitFailed)?;
 
-                trace!(self.logger, "Set the new imported cursor");
+        trace!(self.backend.logger, "Setting the new imported cursor");
 
         // and set it
         if crtc::set_cursor2(
-                    self.graphics.head().head().head(),
-                    self.crtc,
+            &*self.backend.context,
+            self.backend.crtc,
             &cursor,
             (hotspot.0 as i32, hotspot.1 as i32),
         ).is_err()
         {
-                    crtc::set_cursor(self.graphics.head().head().head(), self.crtc, &cursor).chain_err(
-                        || ErrorKind::DrmDev(format!("{:?}", self.graphics.head().head().head())),
-                    )?;
+            crtc::set_cursor(&*self.backend.context, self.backend.crtc, &cursor).chain_err(|| {
+                ErrorKind::DrmDev(format!(
+                    "Failed to set cursor on {:?}",
+                    self.backend.context.dev_path()
+                ))
+            })?;
         }
 
         // and store it
-                cursor
-            });
+        self.backend.cursor.set(cursor);
         Ok(())
-        })
     }
 }
 
-impl EGLGraphicsBackend for DrmBackend {
+impl<A: Device + 'static> EGLGraphicsBackend for DrmBackend<A> {
     fn swap_buffers(&self) -> ::std::result::Result<(), SwapBuffersError> {
-        self.graphics.rent_all(|graphics| {
-            // We cannot call lock_front_buffer anymore without releasing the previous buffer, which will happen when the page flip is done
-            if graphics.gbm.surface.rent(|egl| {
-                let next = egl.buffers.next_buffer.take();
-                let res = next.is_some();
-                egl.buffers.next_buffer.set(next);
+        if {
+            let nb = self.backend.next_buffer.take();
+            let res = nb.is_some();
+            self.backend.next_buffer.set(nb);
             res
-            }) {
-                warn!(self.logger, "Tried to swap a DrmBackend with a queued flip");
+        } {
+            // We cannot call lock_front_buffer anymore without releasing the previous buffer, which will happen when the page flip is done
+            warn!(
+                self.backend.logger,
+                "Tried to swap a DrmBackend with a queued flip"
+            );
             return Err(SwapBuffersError::AlreadySwapped);
         }
 
         // flip normally
-            graphics.gbm.surface.rent(|egl| egl.surface.swap_buffers())?;
+        self.surface.swap_buffers()?;
 
-            graphics.gbm.surface.rent_all(|surface| {
-                // supporting this error would cause a lot of inconvinience and
+        // supporting only one buffer would cause a lot of inconvinience and
         // would most likely result in a lot of flickering.
         // neither weston, wlc or wlroots bother with that as well.
-                // so we just assume we got at least two buffers to do flipping
-                let mut next_bo = surface
-                    .gbm
+        // so we just assume we got at least two buffers to do flipping.
+        let mut next_bo = self.surface
             .lock_front_buffer()
             .expect("Surface only has one front buffer. Not supported by smithay");
 
         // create a framebuffer if the front buffer does not have one already
         // (they are reused by gbm)
-                let maybe_fb = next_bo.userdata().cloned();
+        let maybe_fb = next_bo
+            .userdata()
+            .map_err(|_| SwapBuffersError::ContextLost)?
+            .cloned();
         let fb = if let Some(info) = maybe_fb {
             info
         } else {
-                    let fb = framebuffer::create(graphics.context.devices.drm, &*next_bo)
+            let fb = framebuffer::create(&*self.backend.context, &*next_bo)
                 .map_err(|_| SwapBuffersError::ContextLost)?;
-                    next_bo.set_userdata(fb);
+            next_bo.set_userdata(fb).unwrap();
             fb
         };
-                surface.egl.buffers.next_buffer.set(Some(next_bo));
+        self.backend.next_buffer.set(Some(next_bo));
 
-                trace!(self.logger, "Queueing Page flip");
-
-                // and flip
-                crtc::page_flip(
-                    graphics.context.devices.drm,
-                    self.crtc,
-                    fb.handle(),
-                    &[crtc::PageFlipFlags::PageFlipEvent],
-                ).map_err(|_| SwapBuffersError::ContextLost)
-            })
-        })
+        self.backend.page_flip(Some(&fb))
     }
 
     unsafe fn get_proc_address(&self, symbol: &str) -> *const c_void {
-        self.graphics
-            .head()
-            .rent(|context| context.get_proc_address(symbol))
+        self.backend.context.get_proc_address(symbol)
     }
 
     fn get_framebuffer_dimensions(&self) -> (u32, u32) {
@@ -524,19 +511,20 @@ impl EGLGraphicsBackend for DrmBackend {
     }
 
     fn is_current(&self) -> bool {
-        self.graphics.rent_all(|graphics| {
-            graphics.context.egl.is_current() && graphics.gbm.surface.rent(|egl| egl.surface.is_current())
-        })
+        self.backend.context.is_current() && self.surface.is_current()
     }
 
     unsafe fn make_current(&self) -> ::std::result::Result<(), SwapBuffersError> {
-        self.graphics
-            .rent(|gbm| gbm.surface.rent(|egl| egl.surface.make_current()))
+        self.surface.make_current()
     }
 
     fn get_pixel_format(&self) -> PixelFormat {
-        self.graphics
-            .head()
-            .rent(|context| context.get_pixel_format())
+        self.backend.context.get_pixel_format()
+    }
+}
+
+impl<A: Device + 'static> EGLWaylandExtensions for DrmBackend<A> {
+    fn bind_wl_display(&self, display: &Display) -> EGLResult<EGLDisplay> {
+        self.backend.context.bind_wl_display(display)
     }
 }

src/backend/drm/error.rs

@@ -2,9 +2,8 @@
 //! Errors thrown by the `DrmDevice` and `DrmBackend`
 //!
 
-use backend::graphics::egl;
+use backend::graphics::egl::error as egl;
 use drm::control::{connector, crtc, Mode};
-use rental::TryNewError;
 
 error_chain! {
     errors {
@@ -19,6 +18,11 @@ error_chain! {
             display("The drm device ({:?}) encountered an access error", dev),
         }
 
+        #[doc = "Unable to determine device id of drm device"]
+        UnableToGetDeviceId {
+            description("Unable to determine device id of drm device"),
+        }
+
         #[doc = "Creation of gbm resource failed"]
         GbmInitFailed {
             description("Creation of gbm resource failed"),
@@ -60,9 +64,3 @@ error_chain! {
         EGL(egl::Error, egl::ErrorKind) #[doc = "EGL error"];
     }
 }
-
-impl<H> From<TryNewError<Error, H>> for Error {
-    fn from(err: TryNewError<Error, H>) -> Error {
-        err.0
-    }
-}

src/backend/drm/mod.rs

@@ -44,23 +44,37 @@
 //! extern crate smithay;
 //! extern crate wayland_server;
 //!
+//! use drm::Device as BasicDevice;
 //! use drm::control::{Device as ControlDevice, ResourceInfo};
 //! use drm::control::connector::{Info as ConnectorInfo, State as ConnectorState};
 //! use drm::control::encoder::{Info as EncoderInfo};
-//! use std::fs::OpenOptions;
+//! use std::fs::{File, OpenOptions};
+//! use std::os::unix::io::RawFd;
+//! use std::os::unix::io::AsRawFd;
 //! use smithay::backend::drm::{DrmDevice, DrmBackend};
 //! use wayland_server::StateToken;
 //!
-//! # fn main() {
+//! #[derive(Debug)]
+//! pub struct Card(File);
 //!
+//! impl AsRawFd for Card {
+//!     fn as_raw_fd(&self) -> RawFd {
+//!         self.0.as_raw_fd()
+//!     }
+//! }
+//!
+//! impl BasicDevice for Card {}
+//! impl ControlDevice for Card {}
+//!
+//! # fn main() {
 //! let (_display, mut event_loop) = wayland_server::create_display();
 //!
 //! // Open the drm device
 //! let mut options = OpenOptions::new();
 //! options.read(true);
 //! options.write(true);
-//! let mut device = DrmDevice::new_from_file(
-//!     options.open("/dev/dri/card0").unwrap(), // try to detect it properly
+//! let mut device = DrmDevice::new(
+//!     Card(options.open("/dev/dri/card0").unwrap()), // try to detect it properly
 //!     None /*put a logger here*/
 //! ).unwrap();
 //!
@@ -89,12 +103,11 @@
 //! let mode = connector_info.modes()[0];
 //!
 //! // Create the backend
-//! let backend: StateToken<DrmBackend> = device.create_backend(
-//!     event_loop.state(),
+//! let backend = device.create_backend(
 //!     crtc,
 //!     mode,
 //!     vec![connector_info.handle()]
-//! ).unwrap().clone();
+//! ).unwrap();
 //! # }
 //! ```
 //!
@@ -116,15 +129,27 @@
 //! # extern crate smithay;
 //! # extern crate wayland_server;
 //! #
+//! # use drm::Device as BasicDevice;
 //! # use drm::control::{Device as ControlDevice, ResourceInfo};
 //! # use drm::control::connector::{Info as ConnectorInfo, State as ConnectorState};
 //! use drm::control::crtc::{Handle as CrtcHandle};
 //! use drm::result::Error as DrmError;
-//! # use std::fs::OpenOptions;
+//! # use std::fs::{File, OpenOptions};
+//! # use std::os::unix::io::RawFd;
+//! # use std::os::unix::io::AsRawFd;
 //! # use std::time::Duration;
 //! use smithay::backend::drm::{DrmDevice, DrmBackend, DrmHandler, drm_device_bind};
 //! use smithay::backend::graphics::egl::EGLGraphicsBackend;
-//! use wayland_server::{StateToken, StateProxy};
+//! #
+//! # #[derive(Debug)]
+//! # pub struct Card(File);
+//! # impl AsRawFd for Card {
+//! #     fn as_raw_fd(&self) -> RawFd {
+//! #         self.0.as_raw_fd()
+//! #     }
+//! # }
+//! # impl BasicDevice for Card {}
+//! # impl ControlDevice for Card {}
 //! #
 //! # fn main() {
 //! #
@@ -133,8 +158,8 @@
 //! # let mut options = OpenOptions::new();
 //! # options.read(true);
 //! # options.write(true);
-//! # let mut device = DrmDevice::new_from_file(
-//! #     options.open("/dev/dri/card0").unwrap(), // try to detect it properly
+//! # let mut device = DrmDevice::new(
+//! #     Card(options.open("/dev/dri/card0").unwrap()), // try to detect it properly
 //! #     None /*put a logger here*/
 //! # ).unwrap();
 //! #
@@ -145,32 +170,28 @@
 //! #     .unwrap();
 //! # let crtc = res_handles.crtcs()[0];
 //! # let mode = connector_info.modes()[0];
-//! # let backend: StateToken<DrmBackend> = device.create_backend(
-//! #     event_loop.state(),
+//! # let backend = device.create_backend(
 //! #     crtc,
 //! #     mode,
 //! #     vec![connector_info.handle()]
-//! # ).unwrap().clone();
+//! # ).unwrap();
 //!
-//! struct MyDrmHandler;
+//! struct MyDrmHandler(DrmBackend<Card>);
 //!
-//! impl DrmHandler<DrmBackend> for MyDrmHandler {
-//!     fn ready<'a, S: Into<StateProxy<'a>>>(
+//! impl DrmHandler<Card> for MyDrmHandler {
+//!     fn ready(
 //!         &mut self,
-//!         state: S,
-//!         _device: &mut DrmDevice<DrmBackend>,
-//!         backend: &StateToken<DrmBackend>,
+//!         _device: &mut DrmDevice<Card>,
 //!         _crtc: CrtcHandle,
 //!         _frame: u32,
 //!         _duration: Duration)
 //!     {
 //!         // render surfaces and swap again
-//!         state.into().get(backend).swap_buffers().unwrap();
+//!         self.0.swap_buffers().unwrap();
 //!     }
-//!     fn error<'a, S: Into<StateProxy<'a>>>(
+//!     fn error(
 //!         &mut self,
-//!         _state: S,
-//!         device: &mut DrmDevice<DrmBackend>,
+//!         device: &mut DrmDevice<Card>,
 //!         error: DrmError)
 //!     {
 //!         panic!("DrmDevice errored: {}", error);
@@ -178,115 +199,72 @@
 //! }
 //!
 //! // render something (like clear_color)
-//! event_loop.state().get(&backend).swap_buffers().unwrap();
+//! backend.swap_buffers().unwrap();
 //!
 //! let device_token = event_loop.state().insert(device);
-//! let _source = drm_device_bind(&mut event_loop, device_token, MyDrmHandler).unwrap();
+//! let _source = drm_device_bind(&mut event_loop, device_token, MyDrmHandler(backend)).unwrap();
 //!
 //! event_loop.run().unwrap();
 //! # }
 //! ```
 
-use backend::graphics::egl::{EGLContext, GlAttributes, PixelFormatRequirements};
-use backend::graphics::egl::EGLGraphicsBackend;
+use backend::graphics::egl::context::{EGLContext, GlAttributes};
+use backend::graphics::egl::error::Result as EGLResult;
+use backend::graphics::egl::native::Gbm;
+use backend::graphics::egl::wayland::{EGLDisplay, EGLWaylandExtensions};
 #[cfg(feature = "backend_session")]
 use backend::session::SessionObserver;
 use drm::Device as BasicDevice;
 use drm::control::{connector, crtc, encoder, Mode, ResourceInfo};
 use drm::control::Device as ControlDevice;
+use drm::control::framebuffer;
 use drm::result::Error as DrmError;
 use gbm::Device as GbmDevice;
 use nix;
-use nix::Result as NixResult;
-use nix::unistd::close;
-use std::borrow::Borrow;
+use nix::sys::stat::{dev_t, fstat};
 use std::collections::HashMap;
-use std::fs::File;
 use std::hash::{Hash, Hasher};
 use std::io::Result as IoResult;
-use std::mem;
-use std::os::unix::io::{AsRawFd, IntoRawFd, RawFd};
-use std::rc::Rc;
+use std::os::unix::io::{AsRawFd, RawFd};
+use std::path::PathBuf;
+use std::rc::{Rc, Weak};
+use std::sync::{Once, ONCE_INIT};
 use std::time::Duration;
-use wayland_server::{EventLoopHandle, StateProxy, StateToken};
+use wayland_server::{Display, EventLoopHandle, StateToken};
+#[cfg(feature = "backend_session")]
+use wayland_server::StateProxy;
 use wayland_server::sources::{FdEventSource, FdEventSourceImpl, FdInterest};
 
 mod backend;
 pub mod error;
 
 pub use self::backend::DrmBackend;
+use self::backend::DrmBackendInternal;
 use self::error::*;
 
-/// Internal struct as required by the drm crate
-#[derive(Debug)]
-pub(crate) struct DrmDev(RawFd);
-
-impl AsRawFd for DrmDev {
-    fn as_raw_fd(&self) -> RawFd {
-        self.0
-    }
-}
-impl BasicDevice for DrmDev {}
-impl ControlDevice for DrmDev {}
-
-impl DrmDev {
-    unsafe fn new_from_fd(fd: RawFd) -> Self {
-        DrmDev(fd)
-    }
-
-    fn new_from_file(file: File) -> Self {
-        DrmDev(file.into_raw_fd())
-    }
-}
-
-rental! {
-    mod devices {
-        use drm::control::framebuffer;
-        use gbm::{Device as GbmDevice, Surface as GbmSurface};
-
-        use ::backend::graphics::egl::EGLContext;
-        use super::DrmDev;
-
-        #[rental]
-        pub(crate) struct Context {
-            #[subrental(arity = 2)]
-            devices: Box<Devices>,
-            egl: EGLContext<'devices_1, GbmSurface<'devices_1, framebuffer::Info>>,
-        }
-
-        #[rental]
-        pub(crate) struct Devices {
-            drm: Box<DrmDev>,
-            gbm: GbmDevice<'drm>,
-        }
-    }
-}
-use self::devices::{Context, Devices};
+static LOAD: Once = ONCE_INIT;
 
 /// Representation of an open drm device node to create rendering backends
-pub struct DrmDevice<B: Borrow<DrmBackend> + 'static> {
-    context: Rc<Context>,
-    backends: HashMap<crtc::Handle, StateToken<B>>,
+pub struct DrmDevice<A: ControlDevice + 'static> {
+    context: Rc<EGLContext<Gbm<framebuffer::Info>, GbmDevice<A>>>,
     old_state: HashMap<crtc::Handle, (crtc::Info, Vec<connector::Handle>)>,
+    device_id: dev_t,
+    backends: HashMap<crtc::Handle, Weak<DrmBackendInternal<A>>>,
     active: bool,
     logger: ::slog::Logger,
 }
 
-impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
-    /// Create a new `DrmDevice` from a raw file descriptor
+impl<A: ControlDevice + 'static> DrmDevice<A> {
+    /// Create a new `DrmDevice` from an open drm node
     ///
-    /// Returns an error of opening the device failed or context creation was not
+    /// Returns an error if the file is no valid drm node or context creation was not
     /// successful.
-    ///
-    /// # Safety
-    /// The file descriptor might not be valid and needs to be owned by smithay,
-    /// make sure not to share it. Otherwise undefined behavior might occur.
-    pub unsafe fn new_from_fd<L>(fd: RawFd, logger: L) -> Result<Self>
+    pub fn new<L>(dev: A, logger: L) -> Result<Self>
     where
         L: Into<Option<::slog::Logger>>,
     {
-        DrmDevice::new(
-            DrmDev::new_from_fd(fd),
+        DrmDevice::new_with_gl_attr(
+            dev,
             GlAttributes {
                 version: None,
                 profile: None,
@@ -297,53 +275,11 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
         )
     }
 
-    /// Create a new `DrmDevice` from a raw file descriptor and given `GlAttributes`
-    ///
-    /// Returns an error of opening the device failed or context creation was not
-    /// successful.
-    ///
-    /// # Safety
-    /// The file descriptor might not be valid and needs to be owned by smithay,
-    /// make sure not to share it. Otherwise undefined behavior might occur.
-    pub unsafe fn new_from_fd_with_gl_attr<L>(fd: RawFd, attributes: GlAttributes, logger: L) -> Result<Self>
-    where
-        L: Into<Option<::slog::Logger>>,
-    {
-        DrmDevice::new(DrmDev::new_from_fd(fd), attributes, logger)
-    }
-
-    /// Create a new `DrmDevice` from a `File` of an open drm node
+    /// Create a new `DrmDevice` from an open drm node and given `GlAttributes`
     ///
     /// Returns an error if the file is no valid drm node or context creation was not
     /// successful.
-    pub fn new_from_file<L>(file: File, logger: L) -> Result<Self>
-    where
-        L: Into<Option<::slog::Logger>>,
-    {
-        DrmDevice::new(
-            DrmDev::new_from_file(file),
-            GlAttributes {
-                version: None,
-                profile: None,
-                debug: cfg!(debug_assertions),
-                vsync: true,
-            },
-            logger,
-        )
-    }
-
-    /// Create a new `DrmDevice` from a `File` of an open drm node and given `GlAttributes`
-    ///
-    /// Returns an error if the file is no valid drm node or context creation was not
-    /// successful.
-    pub fn new_from_file_with_gl_attr<L>(file: File, attributes: GlAttributes, logger: L) -> Result<Self>
-    where
-        L: Into<Option<::slog::Logger>>,
-    {
-        DrmDevice::new(DrmDev::new_from_file(file), attributes, logger)
-    }
-
-    fn new<L>(drm: DrmDev, attributes: GlAttributes, logger: L) -> Result<Self>
+    pub fn new_with_gl_attr<L>(dev: A, attributes: GlAttributes, logger: L) -> Result<Self>
     where
         L: Into<Option<::slog::Logger>>,
     {
@@ -355,31 +291,67 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
          * and loading the DRI driver fails.
          * Workaround this by dlopen()'ing libglapi with RTLD_GLOBAL.
          */
-        unsafe {
+        LOAD.call_once(|| unsafe {
             nix::libc::dlopen(
                 "libglapi.so.0".as_ptr() as *const _,
                 nix::libc::RTLD_LAZY | nix::libc::RTLD_GLOBAL,
             );
-        }
+        });
+
+        let device_id = fstat(dev.as_raw_fd())
+            .chain_err(|| ErrorKind::UnableToGetDeviceId)?
+            .st_rdev;
+
+        let mut drm = DrmDevice {
+            // Open the gbm device from the drm device and create a context based on that
+            context: Rc::new(EGLContext::new(
+                {
+                    debug!(log, "Creating gbm device");
+                    let gbm = GbmDevice::new(dev).chain_err(|| ErrorKind::GbmInitFailed)?;
+                    debug!(log, "Creating egl context from gbm device");
+                    gbm
+                },
+                attributes,
+                Default::default(),
+                log.clone(),
+            ).map_err(Error::from)?),
+            backends: HashMap::new(),
+            device_id,
+            old_state: HashMap::new(),
+            active: true,
+            logger: log.clone(),
+        };
 
         info!(log, "DrmDevice initializing");
 
         // we want to mode-set, so we better be the master
         drm.set_master().chain_err(|| ErrorKind::DrmMasterFailed)?;
 
-        let mut old_state = HashMap::new();
-        let res_handles = drm.resource_handles()
-            .chain_err(|| ErrorKind::DrmDev(format!("Loading drm resources on {:?}", drm)))?;
+        let res_handles = drm.resource_handles().chain_err(|| {
+            ErrorKind::DrmDev(format!(
+                "Error loading drm resources on {:?}",
+                drm.dev_path()
+            ))
+        })?;
         for &con in res_handles.connectors() {
-            let con_info = connector::Info::load_from_device(&drm, con)
-                .chain_err(|| ErrorKind::DrmDev(format!("Loading connector info on {:?}", drm)))?;
+            let con_info = connector::Info::load_from_device(&drm, con).chain_err(|| {
+                ErrorKind::DrmDev(format!(
+                    "Error loading connector info on {:?}",
+                    drm.dev_path()
+                ))
+            })?;
             if let Some(enc) = con_info.current_encoder() {
-                let enc_info = encoder::Info::load_from_device(&drm, enc)
-                    .chain_err(|| ErrorKind::DrmDev(format!("Loading encoder info on {:?}", drm)))?;
+                let enc_info = encoder::Info::load_from_device(&drm, enc).chain_err(|| {
+                    ErrorKind::DrmDev(format!(
+                        "Error loading encoder info on {:?}",
+                        drm.dev_path()
+                    ))
+                })?;
                 if let Some(crtc) = enc_info.current_crtc() {
-                    let info = crtc::Info::load_from_device(&drm, crtc)
-                        .chain_err(|| ErrorKind::DrmDev(format!("Loading crtc info on {:?}", drm)))?;
-                    old_state
+                    let info = crtc::Info::load_from_device(&drm, crtc).chain_err(|| {
+                        ErrorKind::DrmDev(format!("Error loading crtc info on {:?}", drm.dev_path()))
+                    })?;
+                    drm.old_state
                         .entry(crtc)
                         .or_insert((info, Vec::new()))
                         .1
@@ -388,33 +360,7 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
             }
         }
 
-        // Open the gbm device from the drm device and create a context based on that
-        Ok(DrmDevice {
-            context: Rc::new(Context::try_new(
-                Box::new(Devices::try_new(Box::new(drm), |drm| {
-                    debug!(log, "Creating gbm device");
-                    GbmDevice::new_from_drm(drm).chain_err(|| ErrorKind::GbmInitFailed)
-                })?),
-                |devices| {
-                    debug!(log, "Creating egl context from gbm device");
-                    EGLContext::new_from_gbm(
-                        devices.gbm,
-                        attributes,
-                        PixelFormatRequirements {
-                            hardware_accelerated: Some(true),
-                            color_bits: Some(24),
-                            alpha_bits: Some(8),
-                            ..Default::default()
-                        },
-                        log.clone(),
-                    ).map_err(Error::from)
-                },
-            )?),
-            backends: HashMap::new(),
-            old_state,
-            active: true,
-            logger: log,
-        })
+        Ok(drm)
     }
 
     /// Create a new backend on a given crtc with a given `Mode` for a given amount
@@ -422,12 +368,11 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
     ///
     /// Errors if initialization fails or the mode is not available on all given
     /// connectors.
-    pub fn create_backend<'a, I, S>(
-        &mut self, state: S, crtc: crtc::Handle, mode: Mode, connectors: I
-    ) -> Result<&StateToken<B>>
+    pub fn create_backend<I>(
+        &mut self, crtc: crtc::Handle, mode: Mode, connectors: I
+    ) -> Result<DrmBackend<A>>
     where
         I: Into<Vec<connector::Handle>>,
-        S: Into<StateProxy<'a>>,
     {
         if self.backends.contains_key(&crtc) {
             bail!(ErrorKind::CrtcAlreadyInUse(crtc));
@@ -442,11 +387,10 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
 
         // check if we have an encoder for every connector and the mode mode
         for connector in &connectors {
-            let con_info = connector::Info::load_from_device(self.context.head().head(), *connector)
-                .chain_err(|| {
+            let con_info = connector::Info::load_from_device(self, *connector).chain_err(|| {
                 ErrorKind::DrmDev(format!(
-                        "Loading connector info on {:?}",
-                        self.context.head().head()
+                    "Error loading connector info on {:?}",
+                    self.dev_path()
                 ))
             })?;
 
@@ -460,10 +404,10 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
                 .encoders()
                 .iter()
                 .map(|encoder| {
-                    encoder::Info::load_from_device(self.context.head().head(), *encoder).chain_err(|| {
+                    encoder::Info::load_from_device(self, *encoder).chain_err(|| {
                         ErrorKind::DrmDev(format!(
-                            "Loading encoder info on {:?}",
-                            self.context.head().head()
+                            "Error loading encoder info on {:?}",
+                            self.dev_path()
                         ))
                     })
                 })
@@ -472,8 +416,8 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
             // and if any encoder supports the selected crtc
             let resource_handles = self.resource_handles().chain_err(|| {
                 ErrorKind::DrmDev(format!(
-                    "Loading drm resources on {:?}",
-                    self.context.head().head()
+                    "Error loading drm resources on {:?}",
+                    self.dev_path()
                 ))
             })?;
             if !encoders
@@ -489,65 +433,67 @@ impl<B: From<DrmBackend> + Borrow<DrmBackend> + 'static> DrmDevice<B> {
 
         let logger = self.logger.new(o!("crtc" => format!("{:?}", crtc)));
         let backend = DrmBackend::new(self.context.clone(), crtc, mode, connectors, logger)?;
-        self.backends
-            .insert(crtc, state.into().insert(backend.into()));
-
-        Ok(self.backends.get(&crtc).unwrap())
+        self.backends.insert(crtc, backend.weak());
+        Ok(backend)
     }
 
-    /// Get the current backend for a given crtc if any
-    pub fn backend_for_crtc(&self, crtc: &crtc::Handle) -> Option<&StateToken<B>> {
-        self.backends.get(crtc)
-    }
-
-    /// Get all belonging backends
-    pub fn current_backends(&self) -> Vec<&StateToken<B>> {
-        self.backends.values().collect()
-    }
-
-    /// Destroy the backend using a given crtc if any
-    ///
-    /// ## Panics
-    /// Panics if the backend is already borrowed from the state
-    pub fn destroy_backend<'a, S>(&mut self, state: S, crtc: &crtc::Handle)
-    where
-        S: Into<StateProxy<'a>>,
-    {
-        if let Some(token) = self.backends.remove(crtc) {
-            state.into().remove(token);
+    /// Returns an internal device id, that is unique per boot per system
+    pub fn device_id(&self) -> u64 {
+        self.device_id
     }
 }
 
-    /// Close the device
-    ///
-    /// ## Warning
-    /// Never call this function if the device is managed by another backend e.g. the `UdevBackend`.
-    /// Only use this function for manually initialized devices.
-    pub fn close(self) -> NixResult<()> {
-        let fd = self.as_raw_fd();
-        mem::drop(self);
-        close(fd)
+/// Trait for types representing open devices
+pub trait DevPath {
+    /// Returns the path of the open device if possible
+    fn dev_path(&self) -> Option<PathBuf>;
+}
+
+impl<A: AsRawFd> DevPath for A {
+    fn dev_path(&self) -> Option<PathBuf> {
+        use std::fs;
+
+        fs::read_link(format!("/proc/self/fd/{:?}", self.as_raw_fd())).ok()
+    }
+}
+
+impl<A: ControlDevice + 'static> PartialEq for DrmDevice<A> {
+    fn eq(&self, other: &DrmDevice<A>) -> bool {
+        self.device_id == other.device_id
+    }
+}
+impl<A: ControlDevice + 'static> Eq for DrmDevice<A> {}
+
+impl<A: ControlDevice + 'static> Hash for DrmDevice<A> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.device_id.hash(state);
     }
 }
 
 // for users convinience and FdEventSource registering
-impl<B: Borrow<DrmBackend> + 'static> AsRawFd for DrmDevice<B> {
+impl<A: ControlDevice + 'static> AsRawFd for DrmDevice<A> {
     fn as_raw_fd(&self) -> RawFd {
-        self.context.head().head().as_raw_fd()
+        self.context.as_raw_fd()
     }
 }
 
-impl<B: Borrow<DrmBackend> + 'static> BasicDevice for DrmDevice<B> {}
-impl<B: Borrow<DrmBackend> + 'static> ControlDevice for DrmDevice<B> {}
+impl<A: ControlDevice + 'static> BasicDevice for DrmDevice<A> {}
+impl<A: ControlDevice + 'static> ControlDevice for DrmDevice<A> {}
 
-impl<B: Borrow<DrmBackend> + 'static> Drop for DrmDevice<B> {
+impl<A: ControlDevice + 'static> EGLWaylandExtensions for DrmDevice<A> {
+    fn bind_wl_display(&self, display: &Display) -> EGLResult<EGLDisplay> {
+        self.context.bind_wl_display(display)
+    }
+}
+
+impl<A: ControlDevice + 'static> Drop for DrmDevice<A> {
     fn drop(&mut self) {
         if Rc::strong_count(&self.context) > 1 {
-            panic!("Pending DrmBackends. Please free all backends before the DrmDevice gets destroyed");
+            panic!("Pending DrmBackends. You need to free all backends before the DrmDevice gets destroyed");
         }
         for (handle, (info, connectors)) in self.old_state.drain() {
             if let Err(err) = crtc::set(
-                self.context.head().head(),
+                &*self.context,
                 handle,
                 info.fb(),
                 &connectors,
@@ -569,49 +515,29 @@ impl<B: Borrow<DrmBackend> + 'static> Drop for DrmDevice<B> {
     }
 }
 
-impl<B: Borrow<DrmBackend> + 'static> Hash for DrmDevice<B> {
-    fn hash<H: Hasher>(&self, state: &mut H) {
-        self.as_raw_fd().hash(state)
-    }
-}
-
 /// Handler for drm node events
 ///
 /// See module-level documentation for its use
-pub trait DrmHandler<B: Borrow<DrmBackend> + 'static> {
-    /// A `DrmBackend` has finished swapping buffers and new frame can now
+pub trait DrmHandler<A: ControlDevice + 'static> {
+    /// The `DrmBackend` of crtc has finished swapping buffers and new frame can now
     /// (and should be immediately) be rendered.
-    ///
-    /// The `id` argument is the `Id` of the `DrmBackend` that finished rendering,
-    /// check using `DrmBackend::is`.
-    ///
-    /// ## Panics
-    /// The device is already borrowed from the given `state`. Borrowing it again will panic
-    /// and is not necessary as it is already provided via the `device` parameter.
-    fn ready<'a, S: Into<StateProxy<'a>>>(
-        &mut self, state: S, device: &mut DrmDevice<B>, backend: &StateToken<B>, crtc: crtc::Handle,
-        frame: u32, duration: Duration,
-    );
+    fn ready(&mut self, device: &mut DrmDevice<A>, crtc: crtc::Handle, frame: u32, duration: Duration);
     /// The `DrmDevice` has thrown an error.
     ///
     /// The related backends are most likely *not* usable anymore and
     /// the whole stack has to be recreated..
-    ///
-    /// ## Panics
-    /// The device is already borrowed from the given `state`. Borrowing it again will panic
-    /// and is not necessary as it is already provided via the `device` parameter.
-    fn error<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &mut DrmDevice<B>, error: DrmError);
+    fn error(&mut self, device: &mut DrmDevice<A>, error: DrmError);
 }
 
 /// Bind a `DrmDevice` to an `EventLoop`,
 ///
 /// This will cause it to recieve events and feed them into an `DrmHandler`
-pub fn drm_device_bind<B, H>(
-    evlh: &mut EventLoopHandle, device: StateToken<DrmDevice<B>>, handler: H
-) -> IoResult<FdEventSource<(StateToken<DrmDevice<B>>, H)>>
+pub fn drm_device_bind<A, H>(
+    evlh: &mut EventLoopHandle, device: StateToken<DrmDevice<A>>, handler: H
+) -> IoResult<FdEventSource<(StateToken<DrmDevice<A>>, H)>>
 where
-    B: From<DrmBackend> + Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
+    A: ControlDevice + 'static,
+    H: DrmHandler<A> + 'static,
 {
     let fd = evlh.state().get(&device).as_raw_fd();
     evlh.add_fd_event_source(
@@ -622,10 +548,10 @@ where
     )
 }
 
-fn fd_event_source_implementation<B, H>() -> FdEventSourceImpl<(StateToken<DrmDevice<B>>, H)>
+fn fd_event_source_implementation<A, H>() -> FdEventSourceImpl<(StateToken<DrmDevice<A>>, H)>
 where
-    B: From<DrmBackend> + Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
+    A: ControlDevice + 'static,
+    H: DrmHandler<A> + 'static,
 {
     FdEventSourceImpl {
         ready: |evlh, &mut (ref mut dev_token, ref mut handler), _, _| {
@@ -639,44 +565,40 @@ where
             match events {
                 Ok(events) => for event in events {
                     if let crtc::Event::PageFlip(event) = event {
-                        evlh.state().with_value(dev_token, |state, mut dev| {
+                        let dev = evlh.state().get_mut(dev_token);
                         if dev.active {
-                                if let Some(backend_token) = dev.backend_for_crtc(&event.crtc).cloned() {
+                            if let Some(backend) = dev.backends
+                                .get(&event.crtc)
+                                .iter()
+                                .flat_map(|x| x.upgrade())
+                                .next()
+                            {
                                 // we can now unlock the buffer
-                                    state.get(&backend_token).borrow().unlock_buffer();
+                                backend.unlock_buffer();
                                 trace!(logger, "Handling event for backend {:?}", event.crtc);
                                 // and then call the user to render the next frame
-                                    handler.ready(
-                                        state,
-                                        &mut dev,
-                                        &backend_token,
-                                        event.crtc,
-                                        event.frame,
-                                        event.duration,
-                                    );
+                                handler.ready(dev, event.crtc, event.frame, event.duration);
+                            } else {
+                                dev.backends.remove(&event.crtc);
                             }
                         }
-                        });
                     }
                 },
-                Err(err) => evlh.state().with_value(dev_token, |state, mut dev| {
-                    handler.error(state, &mut dev, err)
-                }),
+                Err(err) => handler.error(evlh.state().get_mut(dev_token), err),
             };
         },
         error: |evlh, &mut (ref mut dev_token, ref mut handler), _, error| {
-            evlh.state().with_value(dev_token, |state, mut dev| {
+            let mut dev = evlh.state().get_mut(dev_token);
             warn!(dev.logger, "DrmDevice errored: {}", error);
-                handler.error(state, &mut dev, error.into());
-            })
+            handler.error(&mut dev, error.into());
         },
     }
 }
 
 #[cfg(feature = "backend_session")]
-impl<B: Borrow<DrmBackend> + 'static> SessionObserver for StateToken<DrmDevice<B>> {
+impl<A: ControlDevice + 'static> SessionObserver for StateToken<DrmDevice<A>> {
     fn pause<'a>(&mut self, state: &mut StateProxy<'a>) {
-        let device: &mut DrmDevice<B> = state.get_mut(self);
+        let device = state.get_mut(self);
         device.active = false;
         if let Err(err) = device.drop_master() {
             error!(
@@ -687,7 +609,7 @@ impl<B: Borrow<DrmBackend> + 'static> SessionObserver for StateToken<DrmDevice<B
     }
 
     fn activate<'a>(&mut self, state: &mut StateProxy<'a>) {
-        state.with_value(self, |state, device| {
+        let device = state.get_mut(self);
         device.active = true;
         if let Err(err) = device.set_master() {
             crit!(
@@ -696,18 +618,22 @@ impl<B: Borrow<DrmBackend> + 'static> SessionObserver for StateToken<DrmDevice<B
                 err
             );
         }
-            for token in device.backends.values() {
-                let backend = state.get(token);
-                if let Err(err) = backend.borrow().swap_buffers() {
-                    // TODO handle this better?
+        let mut crtcs = Vec::new();
+        for (crtc, backend) in device.backends.iter() {
+            if let Some(backend) = backend.upgrade() {
+                backend.unlock_buffer();
+                if let Err(err) = backend.page_flip(None) {
                     error!(
                         device.logger,
-                        "Failed to activate crtc ({:?}) again. Error: {}",
-                        backend.borrow().crtc(),
-                        err
+                        "Failed to activate crtc ({:?}) again. Error: {}", crtc, err
                     );
                 }
-            }
-        })
+            } else {
+                crtcs.push(*crtc);
+            }
+        }
+        for crtc in crtcs {
+            device.backends.remove(&crtc);
+        }
     }
 }

src/backend/graphics/egl/context.rs

@@ -0,0 +1,613 @@
+//! EGL context related structs
+
+use super::{ffi, EGLSurface, PixelFormat};
+use super::error::*;
+use super::native;
+#[cfg(feature = "backend_drm")]
+use drm::Device as BasicDevice;
+#[cfg(feature = "backend_drm")]
+use drm::control::Device as ControlDevice;
+#[cfg(feature = "backend_drm")]
+use gbm::Device as GbmDevice;
+use nix::libc::{c_int, c_void};
+use slog;
+use std::ffi::{CStr, CString};
+use std::marker::PhantomData;
+use std::mem;
+use std::ops::{Deref, DerefMut};
+#[cfg(feature = "backend_drm")]
+use std::os::unix::io::{AsRawFd, RawFd};
+use std::ptr;
+use std::rc::Rc;
+
+/// EGL context for rendering
+pub struct EGLContext<B: native::Backend, N: native::NativeDisplay<B>> {
+    native: N,
+    pub(crate) context: Rc<ffi::egl::types::EGLContext>,
+    pub(crate) display: Rc<ffi::egl::types::EGLDisplay>,
+    pub(crate) config_id: ffi::egl::types::EGLConfig,
+    pub(crate) surface_attributes: Vec<c_int>,
+    pixel_format: PixelFormat,
+    pub(crate) wl_drm_support: bool,
+    pub(crate) egl_to_texture_support: bool,
+    logger: slog::Logger,
+    _backend: PhantomData<B>,
+}
+
+impl<B: native::Backend, N: native::NativeDisplay<B>> Deref for EGLContext<B, N> {
+    type Target = N;
+    fn deref(&self) -> &N {
+        &self.native
+    }
+}
+
+impl<B: native::Backend, N: native::NativeDisplay<B>> DerefMut for EGLContext<B, N> {
+    fn deref_mut(&mut self) -> &mut N {
+        &mut self.native
+    }
+}
+
+impl<B: native::Backend, N: native::NativeDisplay<B>> EGLContext<B, N> {
+    /// Create a new `EGLContext` from a given `NativeDisplay`
+    pub fn new<L>(
+        native: N, attributes: GlAttributes, reqs: PixelFormatRequirements, logger: L
+    ) -> Result<EGLContext<B, N>>
+    where
+        L: Into<Option<::slog::Logger>>,
+    {
+        let log = ::slog_or_stdlog(logger.into()).new(o!("smithay_module" => "renderer_egl"));
+        let ptr = native.ptr()?;
+        let (
+            context,
+            display,
+            config_id,
+            surface_attributes,
+            pixel_format,
+            wl_drm_support,
+            egl_to_texture_support,
+        ) = unsafe { EGLContext::<B, N>::new_internal(ptr, attributes, reqs, log.clone()) }?;
+
+        Ok(EGLContext {
+            native,
+            context,
+            display,
+            config_id,
+            surface_attributes,
+            pixel_format,
+            wl_drm_support,
+            egl_to_texture_support,
+            logger: log,
+            _backend: PhantomData,
+        })
+    }
+
+    unsafe fn new_internal(
+        ptr: ffi::NativeDisplayType, mut attributes: GlAttributes, reqs: PixelFormatRequirements,
+        log: ::slog::Logger,
+    ) -> Result<
+        (
+            Rc<ffi::egl::types::EGLContext>,
+            Rc<ffi::egl::types::EGLDisplay>,
+            ffi::egl::types::EGLConfig,
+            Vec<c_int>,
+            PixelFormat,
+            bool,
+            bool,
+        ),
+    > {
+        // If no version is given, try OpenGLES 3.0, if available,
+        // fallback to 2.0 otherwise
+        let version = match attributes.version {
+            Some((3, x)) => (3, x),
+            Some((2, x)) => (2, x),
+            None => {
+                debug!(log, "Trying to initialize EGL with OpenGLES 3.0");
+                attributes.version = Some((3, 0));
+                match EGLContext::<B, N>::new_internal(ptr, attributes, reqs, log.clone()) {
+                    Ok(x) => return Ok(x),
+                    Err(err) => {
+                        warn!(log, "EGL OpenGLES 3.0 Initialization failed with {}", err);
+                        debug!(log, "Trying to initialize EGL with OpenGLES 2.0");
+                        attributes.version = Some((2, 0));
+                        return EGLContext::<B, N>::new_internal(ptr, attributes, reqs, log);
+                    }
+                }
+            }
+            Some((1, x)) => {
+                error!(
+                    log,
+                    "OpenGLES 1.* is not supported by the EGL renderer backend"
+                );
+                bail!(ErrorKind::OpenGlVersionNotSupported((1, x)));
+            }
+            Some(version) => {
+                error!(
+                    log,
+                    "OpenGLES {:?} is unknown and not supported by the EGL renderer backend", version
+                );
+                bail!(ErrorKind::OpenGlVersionNotSupported(version));
+            }
+        };
+
+        ffi::egl::LOAD.call_once(|| {
+            fn constrain<F>(f: F) -> F
+            where
+                F: for<'a> Fn(&'a str) -> *const ::std::os::raw::c_void,
+            {
+                f
+            };
+            ffi::egl::load_with(|sym| {
+                let name = CString::new(sym).unwrap();
+                let symbol = ffi::egl::LIB.get::<*mut c_void>(name.as_bytes());
+                match symbol {
+                    Ok(x) => *x as *const _,
+                    Err(_) => ptr::null(),
+                }
+            });
+            let proc_address = constrain(|sym| {
+                let addr = CString::new(sym).unwrap();
+                let addr = addr.as_ptr();
+                ffi::egl::GetProcAddress(addr) as *const _
+            });
+            ffi::egl::load_with(&proc_address);
+            ffi::egl::BindWaylandDisplayWL::load_with(&proc_address);
+            ffi::egl::UnbindWaylandDisplayWL::load_with(&proc_address);
+            ffi::egl::QueryWaylandBufferWL::load_with(&proc_address);
+            ffi::gl::load_with(&proc_address);
+        });
+
+        // the first step is to query the list of extensions without any display, if supported
+        let dp_extensions = {
+            let p = ffi::egl::QueryString(ffi::egl::NO_DISPLAY, ffi::egl::EXTENSIONS as i32);
+
+            // this possibility is available only with EGL 1.5 or EGL_EXT_platform_base, otherwise
+            // `eglQueryString` returns an error
+            if p.is_null() {
+                vec![]
+            } else {
+                let p = CStr::from_ptr(p);
+                let list = String::from_utf8(p.to_bytes().to_vec()).unwrap_or_else(|_| String::new());
+                list.split(' ').map(|e| e.to_string()).collect::<Vec<_>>()
+            }
+        };
+
+        debug!(log, "EGL No-Display Extensions: {:?}", dp_extensions);
+
+        let display = B::get_display(
+            ptr,
+            |e: &str| dp_extensions.iter().any(|s| s == e),
+            log.clone(),
+        );
+        if display == ffi::egl::NO_DISPLAY {
+            error!(log, "EGL Display is not valid");
+            bail!(ErrorKind::DisplayNotSupported);
+        }
+
+        let egl_version = {
+            let mut major: ffi::egl::types::EGLint = mem::uninitialized();
+            let mut minor: ffi::egl::types::EGLint = mem::uninitialized();
+
+            if ffi::egl::Initialize(display, &mut major, &mut minor) == 0 {
+                bail!(ErrorKind::InitFailed);
+            }
+
+            info!(log, "EGL Initialized");
+            info!(log, "EGL Version: {:?}", (major, minor));
+
+            (major, minor)
+        };
+
+        // the list of extensions supported by the client once initialized is different from the
+        // list of extensions obtained earlier
+        let extensions = if egl_version >= (1, 2) {
+            let p = CStr::from_ptr(ffi::egl::QueryString(display, ffi::egl::EXTENSIONS as i32));
+            let list = String::from_utf8(p.to_bytes().to_vec()).unwrap_or_else(|_| String::new());
+            list.split(' ').map(|e| e.to_string()).collect::<Vec<_>>()
+        } else {
+            vec![]
+        };
+
+        info!(log, "EGL Extensions: {:?}", extensions);
+
+        if egl_version >= (1, 2) && ffi::egl::BindAPI(ffi::egl::OPENGL_ES_API) == 0 {
+            error!(
+                log,
+                "OpenGLES not supported by the underlying EGL implementation"
+            );
+            bail!(ErrorKind::OpenGlesNotSupported);
+        }
+
+        let descriptor = {
+            let mut out: Vec<c_int> = Vec::with_capacity(37);
+
+            if egl_version >= (1, 2) {
+                trace!(log, "Setting COLOR_BUFFER_TYPE to RGB_BUFFER");
+                out.push(ffi::egl::COLOR_BUFFER_TYPE as c_int);
+                out.push(ffi::egl::RGB_BUFFER as c_int);
+            }
+
+            trace!(log, "Setting SURFACE_TYPE to WINDOW");
+
+            out.push(ffi::egl::SURFACE_TYPE as c_int);
+            // TODO: Some versions of Mesa report a BAD_ATTRIBUTE error
+            // if we ask for PBUFFER_BIT as well as WINDOW_BIT
+            out.push((ffi::egl::WINDOW_BIT) as c_int);
+
+            match version {
+                (3, _) => {
+                    if egl_version < (1, 3) {
+                        error!(
+                            log,
+                            "OpenglES 3.* is not supported on EGL Versions lower then 1.3"
+                        );
+                        bail!(ErrorKind::NoAvailablePixelFormat);
+                    }
+                    trace!(log, "Setting RENDERABLE_TYPE to OPENGL_ES3");
+                    out.push(ffi::egl::RENDERABLE_TYPE as c_int);
+                    out.push(ffi::egl::OPENGL_ES3_BIT as c_int);
+                    trace!(log, "Setting CONFORMANT to OPENGL_ES3");
+                    out.push(ffi::egl::CONFORMANT as c_int);
+                    out.push(ffi::egl::OPENGL_ES3_BIT as c_int);
+                }
+                (2, _) => {
+                    if egl_version < (1, 3) {
+                        error!(
+                            log,
+                            "OpenglES 2.* is not supported on EGL Versions lower then 1.3"
+                        );
+                        bail!(ErrorKind::NoAvailablePixelFormat);
+                    }
+                    trace!(log, "Setting RENDERABLE_TYPE to OPENGL_ES2");
+                    out.push(ffi::egl::RENDERABLE_TYPE as c_int);
+                    out.push(ffi::egl::OPENGL_ES2_BIT as c_int);
+                    trace!(log, "Setting CONFORMANT to OPENGL_ES2");
+                    out.push(ffi::egl::CONFORMANT as c_int);
+                    out.push(ffi::egl::OPENGL_ES2_BIT as c_int);
+                }
+                (_, _) => unreachable!(),
+            };
+
+            if let Some(hardware_accelerated) = reqs.hardware_accelerated {
+                out.push(ffi::egl::CONFIG_CAVEAT as c_int);
+                out.push(if hardware_accelerated {
+                    trace!(log, "Setting CONFIG_CAVEAT to NONE");
+                    ffi::egl::NONE as c_int
+                } else {
+                    trace!(log, "Setting CONFIG_CAVEAT to SLOW_CONFIG");
+                    ffi::egl::SLOW_CONFIG as c_int
+                });
+            }
+
+            if let Some(color) = reqs.color_bits {
+                trace!(log, "Setting RED_SIZE to {}", color / 3);
+                out.push(ffi::egl::RED_SIZE as c_int);
+                out.push((color / 3) as c_int);
+                trace!(
+                    log,
+                    "Setting GREEN_SIZE to {}",
+                    color / 3 + if color % 3 != 0 { 1 } else { 0 }
+                );
+                out.push(ffi::egl::GREEN_SIZE as c_int);
+                out.push((color / 3 + if color % 3 != 0 { 1 } else { 0 }) as c_int);
+                trace!(
+                    log,
+                    "Setting BLUE_SIZE to {}",
+                    color / 3 + if color % 3 == 2 { 1 } else { 0 }
+                );
+                out.push(ffi::egl::BLUE_SIZE as c_int);
+                out.push((color / 3 + if color % 3 == 2 { 1 } else { 0 }) as c_int);
+            }
+
+            if let Some(alpha) = reqs.alpha_bits {
+                trace!(log, "Setting ALPHA_SIZE to {}", alpha);
+                out.push(ffi::egl::ALPHA_SIZE as c_int);
+                out.push(alpha as c_int);
+            }
+
+            if let Some(depth) = reqs.depth_bits {
+                trace!(log, "Setting DEPTH_SIZE to {}", depth);
+                out.push(ffi::egl::DEPTH_SIZE as c_int);
+                out.push(depth as c_int);
+            }
+
+            if let Some(stencil) = reqs.stencil_bits {
+                trace!(log, "Setting STENCIL_SIZE to {}", stencil);
+                out.push(ffi::egl::STENCIL_SIZE as c_int);
+                out.push(stencil as c_int);
+            }
+
+            if let Some(multisampling) = reqs.multisampling {
+                trace!(log, "Setting SAMPLES to {}", multisampling);
+                out.push(ffi::egl::SAMPLES as c_int);
+                out.push(multisampling as c_int);
+            }
+
+            if reqs.stereoscopy {
+                error!(log, "Stereoscopy is currently unsupported (sorry!)");
+                bail!(ErrorKind::NoAvailablePixelFormat);
+            }
+
+            out.push(ffi::egl::NONE as c_int);
+            out
+        };
+
+        // calling `eglChooseConfig`
+        let mut config_id = mem::uninitialized();
+        let mut num_configs = mem::uninitialized();
+        if ffi::egl::ChooseConfig(
+            display,
+            descriptor.as_ptr(),
+            &mut config_id,
+            1,
+            &mut num_configs,
+        ) == 0
+        {
+            bail!(ErrorKind::ConfigFailed);
+        }
+        if num_configs == 0 {
+            error!(log, "No matching color format found");
+            bail!(ErrorKind::NoAvailablePixelFormat);
+        }
+
+        // analyzing each config
+        macro_rules! attrib {
+            ($display:expr, $config:expr, $attr:expr) => (
+                {
+                    let mut value = mem::uninitialized();
+                    let res = ffi::egl::GetConfigAttrib($display, $config,
+                                                   $attr as ffi::egl::types::EGLint, &mut value);
+                    if res == 0 {
+                        bail!(ErrorKind::ConfigFailed);
+                    }
+                    value
+                }
+            )
+        };
+
+        let desc = PixelFormat {
+            hardware_accelerated: attrib!(display, config_id, ffi::egl::CONFIG_CAVEAT)
+                != ffi::egl::SLOW_CONFIG as i32,
+            color_bits: attrib!(display, config_id, ffi::egl::RED_SIZE) as u8
+                + attrib!(display, config_id, ffi::egl::BLUE_SIZE) as u8
+                + attrib!(display, config_id, ffi::egl::GREEN_SIZE) as u8,
+            alpha_bits: attrib!(display, config_id, ffi::egl::ALPHA_SIZE) as u8,
+            depth_bits: attrib!(display, config_id, ffi::egl::DEPTH_SIZE) as u8,
+            stencil_bits: attrib!(display, config_id, ffi::egl::STENCIL_SIZE) as u8,
+            stereoscopy: false,
+            double_buffer: true,
+            multisampling: match attrib!(display, config_id, ffi::egl::SAMPLES) {
+                0 | 1 => None,
+                a => Some(a as u16),
+            },
+            srgb: false, // TODO: use EGL_KHR_gl_colorspace to know that
+        };
+
+        info!(log, "Selected color format: {:?}", desc);
+
+        let mut context_attributes = Vec::with_capacity(10);
+
+        if egl_version >= (1, 5) || extensions.iter().any(|s| *s == "EGL_KHR_create_context") {
+            trace!(log, "Setting CONTEXT_MAJOR_VERSION to {}", version.0);
+            context_attributes.push(ffi::egl::CONTEXT_MAJOR_VERSION as i32);
+            context_attributes.push(version.0 as i32);
+            trace!(log, "Setting CONTEXT_MINOR_VERSION to {}", version.1);
+            context_attributes.push(ffi::egl::CONTEXT_MINOR_VERSION as i32);
+            context_attributes.push(version.1 as i32);
+
+            if attributes.debug && egl_version >= (1, 5) {
+                trace!(log, "Setting CONTEXT_OPENGL_DEBUG to TRUE");
+                context_attributes.push(ffi::egl::CONTEXT_OPENGL_DEBUG as i32);
+                context_attributes.push(ffi::egl::TRUE as i32);
+            }
+
+            context_attributes.push(ffi::egl::CONTEXT_FLAGS_KHR as i32);
+            context_attributes.push(0);
+        } else if egl_version >= (1, 3) {
+            trace!(log, "Setting CONTEXT_CLIENT_VERSION to {}", version.0);
+            context_attributes.push(ffi::egl::CONTEXT_CLIENT_VERSION as i32);
+            context_attributes.push(version.0 as i32);
+        }
+
+        context_attributes.push(ffi::egl::NONE as i32);
+
+        trace!(log, "Creating EGL context...");
+        let context = ffi::egl::CreateContext(display, config_id, ptr::null(), context_attributes.as_ptr());
+
+        if context.is_null() {
+            match ffi::egl::GetError() as u32 {
+                ffi::egl::BAD_ATTRIBUTE => bail!(ErrorKind::CreationFailed),
+                err_no => bail!(ErrorKind::Unknown(err_no)),
+            }
+        }
+        debug!(log, "EGL context successfully created");
+
+        let surface_attributes = {
+            let mut out: Vec<c_int> = Vec::with_capacity(3);
+
+            match reqs.double_buffer {
+                Some(true) => {
+                    trace!(log, "Setting RENDER_BUFFER to BACK_BUFFER");
+                    out.push(ffi::egl::RENDER_BUFFER as c_int);
+                    out.push(ffi::egl::BACK_BUFFER as c_int);
+                }
+                Some(false) => {
+                    trace!(log, "Setting RENDER_BUFFER to SINGLE_BUFFER");
+                    out.push(ffi::egl::RENDER_BUFFER as c_int);
+                    out.push(ffi::egl::SINGLE_BUFFER as c_int);
+                }
+                None => {}
+            }
+
+            out.push(ffi::egl::NONE as i32);
+            out
+        };
+
+        info!(log, "EGL context created");
+
+        // make current and get list of gl extensions
+        ffi::egl::MakeCurrent(
+            display as *const _,
+            ptr::null(),
+            ptr::null(),
+            context as *const _,
+        );
+
+        // the list of gl extensions supported by the context
+        let gl_extensions = {
+            let data = CStr::from_ptr(ffi::gl::GetString(ffi::gl::EXTENSIONS) as *const _)
+                .to_bytes()
+                .to_vec();
+            let list = String::from_utf8(data).unwrap();
+            list.split(' ').map(|e| e.to_string()).collect::<Vec<_>>()
+        };
+
+        info!(log, "GL Extensions: {:?}", gl_extensions);
+
+        Ok((
+            Rc::new(context as *const _),
+            Rc::new(display as *const _),
+            config_id,
+            surface_attributes,
+            desc,
+            extensions
+                .iter()
+                .any(|s| *s == "EGL_WL_bind_wayland_display"),
+            gl_extensions
+                .iter()
+                .any(|s| *s == "GL_OES_EGL_image" || *s == "GL_OES_EGL_image_base"),
+        ))
+    }
+
+    /// Creates a surface for rendering
+    pub fn create_surface(&self, args: N::Arguments) -> Result<EGLSurface<B::Surface>> {
+        trace!(self.logger, "Creating EGL window surface.");
+        let res = EGLSurface::new(
+            self,
+            self.native
+                .create_surface(args)
+                .chain_err(|| ErrorKind::SurfaceCreationFailed)?,
+        );
+        if res.is_ok() {
+            debug!(self.logger, "EGL surface successfully created");
+        }
+        res
+    }
+
+    /// Returns the address of an OpenGL function.
+    ///
+    /// Supposes that the context has been made current before this function is called.
+    pub unsafe fn get_proc_address(&self, symbol: &str) -> *const c_void {
+        let addr = CString::new(symbol.as_bytes()).unwrap();
+        let addr = addr.as_ptr();
+        ffi::egl::GetProcAddress(addr) as *const _
+    }
+
+    /// Returns true if the OpenGL context is the current one in the thread.
+    pub fn is_current(&self) -> bool {
+        unsafe { ffi::egl::GetCurrentContext() == (*self.context) as *const _ }
+    }
+
+    /// Returns the pixel format of the main framebuffer of the context.
+    pub fn get_pixel_format(&self) -> PixelFormat {
+        self.pixel_format
+    }
+}
+
+unsafe impl<B: native::Backend, N: native::NativeDisplay<B> + Send> Send for EGLContext<B, N> {}
+unsafe impl<B: native::Backend, N: native::NativeDisplay<B> + Sync> Sync for EGLContext<B, N> {}
+
+impl<B: native::Backend, N: native::NativeDisplay<B>> Drop for EGLContext<B, N> {
+    fn drop(&mut self) {
+        unsafe {
+            // we don't call MakeCurrent(0, 0) because we are not sure that the context
+            // is still the current one
+            ffi::egl::DestroyContext((*self.display) as *const _, (*self.context) as *const _);
+            ffi::egl::Terminate((*self.display) as *const _);
+        }
+    }
+}
+
+#[cfg(feature = "backend_drm")]
+impl<T: 'static, A: AsRawFd + 'static> AsRawFd for EGLContext<native::Gbm<T>, GbmDevice<A>> {
+    fn as_raw_fd(&self) -> RawFd {
+        self.native.as_raw_fd()
+    }
+}
+
+#[cfg(feature = "backend_drm")]
+impl<T: 'static, A: BasicDevice + 'static> BasicDevice for EGLContext<native::Gbm<T>, GbmDevice<A>> {}
+#[cfg(feature = "backend_drm")]
+impl<T: 'static, A: ControlDevice + 'static> ControlDevice for EGLContext<native::Gbm<T>, GbmDevice<A>> {}
+
+/// Attributes to use when creating an OpenGL context.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct GlAttributes {
+    /// Describes the OpenGL API and version that are being requested when a context is created.
+    ///
+    /// `Some(3, 0)` will request a OpenGL ES 3.0 context for example.
+    /// `None` means "don't care" (minimum will be 2.0).
+    pub version: Option<(u8, u8)>,
+    /// OpenGL profile to use
+    pub profile: Option<GlProfile>,
+    /// Whether to enable the debug flag of the context.
+    ///
+    /// Debug contexts are usually slower but give better error reporting.
+    pub debug: bool,
+    /// Whether to use vsync. If vsync is enabled, calling swap_buffers will block until the screen refreshes.
+    /// This is typically used to prevent screen tearing.
+    pub vsync: bool,
+}
+
+/// Describes the requested OpenGL context profiles.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum GlProfile {
+    /// Include all the immediate more functions and definitions.
+    Compatibility,
+    /// Include all the future-compatible functions and definitions.
+    Core,
+}
+
+/// Describes how the backend should choose a pixel format.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct PixelFormatRequirements {
+    /// If `true`, only hardware-accelerated formats will be conisdered. If `false`, only software renderers.
+    /// `None` means "don't care". Default is `None`.
+    pub hardware_accelerated: Option<bool>,
+    /// Minimum number of bits for the color buffer, excluding alpha. None means "don't care". The default is `None``.
+    pub color_bits: Option<u8>,
+    /// If `true`, the color buffer must be in a floating point format. Default is `false`.
+    ///
+    /// Using floating points allows you to write values outside of the `[0.0, 1.0]` range.
+    pub float_color_buffer: bool,
+    /// Minimum number of bits for the alpha in the color buffer. `None` means "don't care". The default is `None`.
+    pub alpha_bits: Option<u8>,
+    /// Minimum number of bits for the depth buffer. `None` means "don't care". The default value is `None`.
+    pub depth_bits: Option<u8>,
+    /// Minimum number of bits for the depth buffer. `None` means "don't care". The default value is `None`.
+    pub stencil_bits: Option<u8>,
+    /// If `true`, only double-buffered formats will be considered. If `false`, only single-buffer formats.
+    /// `None` means "don't care". The default is `None`.
+    pub double_buffer: Option<bool>,
+    /// Contains the minimum number of samples per pixel in the color, depth and stencil buffers.
+    /// `None` means "don't care". Default is `None`. A value of `Some(0)` indicates that multisampling must not be enabled.
+    pub multisampling: Option<u16>,
+    /// If `true`, only stereoscopic formats will be considered. If `false`, only non-stereoscopic formats.
+    /// The default is `false`.
+    pub stereoscopy: bool,
+}
+
+impl Default for PixelFormatRequirements {
+    fn default() -> Self {
+        PixelFormatRequirements {
+            hardware_accelerated: Some(true),
+            color_bits: Some(24),
+            float_color_buffer: false,
+            alpha_bits: Some(8),
+            depth_bits: Some(24),
+            stencil_bits: Some(8),
+            double_buffer: Some(true),
+            multisampling: None,
+            stereoscopy: false,
+        }
+    }
+}

src/backend/graphics/egl/error.rs

@@ -0,0 +1,82 @@
+//! EGL error types
+
+error_chain! {
+    errors {
+        #[doc = "The requested OpenGL version is not supported"]
+        OpenGlVersionNotSupported(version: (u8, u8)) {
+            description("The requested OpenGL version is not supported."),
+            display("The requested OpenGL version {:?} is not supported.", version),
+        }
+
+        #[doc = "The EGL implementation does not support creating OpenGL ES contexts"]
+        OpenGlesNotSupported {
+            description("The EGL implementation does not support creating OpenGL ES contexts")
+        }
+
+        #[doc = "No available pixel format matched the criteria"]
+        NoAvailablePixelFormat {
+            description("No available pixel format matched the criteria.")
+        }
+
+        #[doc = "Backend does not match the context type"]
+        NonMatchingBackend(expected: &'static str) {
+            description("The expected backend did not match the runtime."),
+            display("The expected backend '{:?}' does not match the runtime.", expected),
+        }
+
+        #[doc = "EGL was unable to optain a valid EGL Display"]
+        DisplayNotSupported {
+            description("EGL was unable to optain a valid EGL Display")
+        }
+
+        #[doc = "eglInitialize returned an error"]
+        InitFailed {
+            description("Failed to initialize EGL")
+        }
+
+        #[doc = "Failed to configure the EGL context"]
+        ConfigFailed {
+            description("Failed to configure the EGL context")
+        }
+
+        #[doc = "Context creation failed as one or more requirements could not be met. Try removing some gl attributes or pixel format requirements"]
+        CreationFailed {
+            description("Context creation failed as one or more requirements could not be met. Try removing some gl attributes or pixel format requirements")
+        }
+
+        #[doc = "eglCreateWindowSurface failed"]
+        SurfaceCreationFailed {
+            description("Failed to create a new EGLSurface")
+        }
+
+        #[doc = "The required EGL extension is not supported by the underlying EGL implementation"]
+        EglExtensionNotSupported(extensions: &'static [&'static str]) {
+            description("The required EGL extension is not supported by the underlying EGL implementation"),
+            display("None of the following EGL extensions is supported by the underlying EGL implementation,
+                     at least one is required: {:?}", extensions)
+        }
+
+        #[doc = "Only one EGLDisplay may be bound to a given WlDisplay at any time"]
+        OtherEGLDisplayAlreadyBound {
+            description("Only one EGLDisplay may be bound to a given WlDisplay at any time")
+        }
+
+        #[doc = "No EGLDisplay is currently bound to this WlDisplay"]
+        NoEGLDisplayBound {
+            description("No EGLDisplay is currently bound to this WlDisplay")
+        }
+
+        #[doc = "Index of plane is out of bounds for EGLImages"]
+        PlaneIndexOutOfBounds {
+            description("Index of plane is out of bounds for EGLImages")
+        }
+
+        #[doc = "Failed to create EGLImages from the buffer"]
+        EGLImageCreationFailed {
+            description("Failed to create EGLImages from the buffer")
+        }
+
+        #[doc = "The reason of failure could not be determined"]
+        Unknown(err_no: u32)
+    }
+}

src/backend/graphics/egl/ffi.rs

@@ -0,0 +1,182 @@
+#![allow(missing_docs)]
+
+pub use nix::libc::{c_long, c_uint, c_void, int32_t, uint64_t};
+
+pub type khronos_utime_nanoseconds_t = khronos_uint64_t;
+pub type khronos_uint64_t = uint64_t;
+pub type khronos_ssize_t = c_long;
+pub type EGLint = int32_t;
+pub type EGLNativeDisplayType = NativeDisplayType;
+pub type EGLNativePixmapType = NativePixmapType;
+pub type EGLNativeWindowType = NativeWindowType;
+pub type NativeDisplayType = *const c_void;
+pub type NativePixmapType = *const c_void;
+pub type NativeWindowType = *const c_void;
+
+#[cfg_attr(feature = "cargo-clippy", allow(clippy))]
+pub mod gl {
+    include!(concat!(env!("OUT_DIR"), "/gl_bindings.rs"));
+}
+
+#[cfg_attr(feature = "cargo-clippy", allow(clippy))]
+pub mod egl {
+    use super::*;
+    use libloading::Library;
+    use std::sync::{Once, ONCE_INIT};
+
+    lazy_static! {
+        pub static ref LIB: Library = {
+            Library::new("libEGL.so.1").expect("Failed to load LibEGL")
+        };
+    }
+
+    pub static LOAD: Once = ONCE_INIT;
+
+    include!(concat!(env!("OUT_DIR"), "/egl_bindings.rs"));
+
+    /*
+     * `gl_generator` cannot generate bindings for the `EGL_WL_bind_wayland_display` extension.
+     *  Lets do it ourselves...
+     */
+
+    #[allow(non_snake_case, unused_variables, dead_code)]
+    #[inline]
+    pub unsafe fn BindWaylandDisplayWL(
+        dpy: types::EGLDisplay, display: *mut __gl_imports::raw::c_void
+    ) -> types::EGLBoolean {
+        __gl_imports::mem::transmute::<
+            _,
+            extern "system" fn(types::EGLDisplay, *mut __gl_imports::raw::c_void) -> types::EGLBoolean,
+        >(wayland_storage::BindWaylandDisplayWL.f)(dpy, display)
+    }
+
+    #[allow(non_snake_case, unused_variables, dead_code)]
+    #[inline]
+    pub unsafe fn UnbindWaylandDisplayWL(
+        dpy: types::EGLDisplay, display: *mut __gl_imports::raw::c_void
+    ) -> types::EGLBoolean {
+        __gl_imports::mem::transmute::<
+            _,
+            extern "system" fn(types::EGLDisplay, *mut __gl_imports::raw::c_void) -> types::EGLBoolean,
+        >(wayland_storage::UnbindWaylandDisplayWL.f)(dpy, display)
+    }
+
+    #[allow(non_snake_case, unused_variables, dead_code)]
+    #[inline]
+    pub unsafe fn QueryWaylandBufferWL(
+        dpy: types::EGLDisplay, buffer: *mut __gl_imports::raw::c_void, attribute: types::EGLint,
+        value: *mut types::EGLint,
+    ) -> types::EGLBoolean {
+        __gl_imports::mem::transmute::<
+            _,
+            extern "system" fn(
+                types::EGLDisplay,
+                *mut __gl_imports::raw::c_void,
+                types::EGLint,
+                *mut types::EGLint,
+            ) -> types::EGLBoolean,
+        >(wayland_storage::QueryWaylandBufferWL.f)(dpy, buffer, attribute, value)
+    }
+
+    mod wayland_storage {
+        use super::FnPtr;
+        use super::__gl_imports::raw;
+        pub static mut BindWaylandDisplayWL: FnPtr = FnPtr {
+            f: super::missing_fn_panic as *const raw::c_void,
+            is_loaded: false,
+        };
+        pub static mut UnbindWaylandDisplayWL: FnPtr = FnPtr {
+            f: super::missing_fn_panic as *const raw::c_void,
+            is_loaded: false,
+        };
+        pub static mut QueryWaylandBufferWL: FnPtr = FnPtr {
+            f: super::missing_fn_panic as *const raw::c_void,
+            is_loaded: false,
+        };
+    }
+
+    #[allow(non_snake_case)]
+    pub mod BindWaylandDisplayWL {
+        use super::{metaloadfn, wayland_storage};
+        use super::FnPtr;
+        use super::__gl_imports::raw;
+
+        #[inline]
+        #[allow(dead_code)]
+        pub fn is_loaded() -> bool {
+            unsafe { wayland_storage::BindWaylandDisplayWL.is_loaded }
+        }
+
+        #[allow(dead_code)]
+        pub fn load_with<F>(mut loadfn: F)
+        where
+            F: FnMut(&str) -> *const raw::c_void,
+        {
+            unsafe {
+                wayland_storage::BindWaylandDisplayWL =
+                    FnPtr::new(metaloadfn(&mut loadfn, "eglBindWaylandDisplayWL", &[]))
+            }
+        }
+    }
+
+    #[allow(non_snake_case)]
+    pub mod UnbindWaylandDisplayWL {
+        use super::{metaloadfn, wayland_storage};
+        use super::FnPtr;
+        use super::__gl_imports::raw;
+
+        #[inline]
+        #[allow(dead_code)]
+        pub fn is_loaded() -> bool {
+            unsafe { wayland_storage::UnbindWaylandDisplayWL.is_loaded }
+        }
+
+        #[allow(dead_code)]
+        pub fn load_with<F>(mut loadfn: F)
+        where
+            F: FnMut(&str) -> *const raw::c_void,
+        {
+            unsafe {
+                wayland_storage::UnbindWaylandDisplayWL =
+                    FnPtr::new(metaloadfn(&mut loadfn, "eglUnbindWaylandDisplayWL", &[]))
+            }
+        }
+    }
+
+    #[allow(non_snake_case)]
+    pub mod QueryWaylandBufferWL {
+        use super::{metaloadfn, wayland_storage};
+        use super::FnPtr;
+        use super::__gl_imports::raw;
+
+        #[inline]
+        #[allow(dead_code)]
+        pub fn is_loaded() -> bool {
+            unsafe { wayland_storage::QueryWaylandBufferWL.is_loaded }
+        }
+
+        #[allow(dead_code)]
+        pub fn load_with<F>(mut loadfn: F)
+        where
+            F: FnMut(&str) -> *const raw::c_void,
+        {
+            unsafe {
+                wayland_storage::QueryWaylandBufferWL =
+                    FnPtr::new(metaloadfn(&mut loadfn, "eglQueryWaylandBufferWL", &[]))
+            }
+        }
+    }
+
+    // Accepted as <target> in eglCreateImageKHR
+    pub const WAYLAND_BUFFER_WL: c_uint = 0x31D5;
+    // Accepted in the <attrib_list> parameter of eglCreateImageKHR:
+    pub const WAYLAND_PLANE_WL: c_uint = 0x31D6;
+    // Possible values for EGL_TEXTURE_FORMAT:
+    pub const TEXTURE_Y_U_V_WL: int32_t = 0x31D7;
+    pub const TEXTURE_Y_UV_WL: int32_t = 0x31D8;
+    pub const TEXTURE_Y_XUXV_WL: int32_t = 0x31D9;
+    pub const TEXTURE_EXTERNAL_WL: int32_t = 0x31DA;
+    // Accepted in the <attribute> parameter of eglQueryWaylandBufferWL:
+    pub const EGL_TEXTURE_FORMAT: int32_t = 0x3080;
+    pub const WAYLAND_Y_INVERTED_WL: int32_t = 0x31DB;
+}

src/backend/graphics/egl/mod.rs

@@ -0,0 +1,150 @@
+//! Common traits and types for egl rendering
+
+// Large parts of this module are taken from
+// https://github.com/tomaka/glutin/tree/044e651edf67a2029eecc650dd42546af1501414/src/api/egl/
+//
+// It therefore falls under glutin's Apache 2.0 license
+// (see https://github.com/tomaka/glutin/tree/044e651edf67a2029eecc650dd42546af1501414/LICENSE)
+
+use super::GraphicsBackend;
+use nix::libc::c_void;
+use std::fmt;
+
+pub mod context;
+pub use self::context::EGLContext;
+pub mod error;
+#[allow(non_camel_case_types, dead_code, unused_mut, non_upper_case_globals)]
+pub mod ffi;
+pub mod native;
+pub mod surface;
+pub use self::surface::EGLSurface;
+pub mod wayland;
+pub use self::wayland::{BufferAccessError, EGLImages, EGLWaylandExtensions};
+
+/// Error that can happen when swapping buffers.
+#[derive(Debug, Clone, PartialEq)]
+pub enum SwapBuffersError {
+    /// The OpenGL context has been lost and needs to be recreated.
+    ///
+    /// All the objects associated to it (textures, buffers, programs, etc.)
+    /// need to be recreated from scratch.
+    ///
+    /// Operations will have no effect. Functions that read textures, buffers, etc.
+    /// from OpenGL will return uninitialized data instead.
+    ///
+    /// A context loss usually happens on mobile devices when the user puts the
+    /// application on sleep and wakes it up later. However any OpenGL implementation
+    /// can theoretically lose the context at any time.
+    ContextLost,
+    /// The buffers have already been swapped.
+    ///
+    /// This error can be returned when `swap_buffers` has been called multiple times
+    /// without any modification in between.
+    AlreadySwapped,
+    /// Unknown GL error
+    Unknown(u32),
+}
+
+impl fmt::Display for SwapBuffersError {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> ::std::result::Result<(), fmt::Error> {
+        use std::error::Error;
+        write!(formatter, "{}", self.description())
+    }
+}
+
+impl ::std::error::Error for SwapBuffersError {
+    fn description(&self) -> &str {
+        match *self {
+            SwapBuffersError::ContextLost => "The context has been lost, it needs to be recreated",
+            SwapBuffersError::AlreadySwapped => {
+                "Buffers are already swapped, swap_buffers was called too many times"
+            }
+            SwapBuffersError::Unknown(_) => "Unknown Open GL error occurred",
+        }
+    }
+
+    fn cause(&self) -> Option<&::std::error::Error> {
+        None
+    }
+}
+
+/// Error that can happen on optional EGL features
+#[derive(Debug, Clone, PartialEq)]
+pub struct EglExtensionNotSupportedError(&'static [&'static str]);
+
+impl fmt::Display for EglExtensionNotSupportedError {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> ::std::result::Result<(), fmt::Error> {
+        write!(
+            formatter,
+            "None of the following EGL extensions is supported by the underlying EGL implementation,
+                     at least one is required: {:?}",
+            self.0
+        )
+    }
+}
+
+impl ::std::error::Error for EglExtensionNotSupportedError {
+    fn description(&self) -> &str {
+        "The required EGL extension is not supported by the underlying EGL implementation"
+    }
+
+    fn cause(&self) -> Option<&::std::error::Error> {
+        None
+    }
+}
+
+/// Describes the pixel format of the main framebuffer
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct PixelFormat {
+    /// is the format hardware accelerated
+    pub hardware_accelerated: bool,
+    /// number of bits used for colors
+    pub color_bits: u8,
+    /// number of bits used for alpha channel
+    pub alpha_bits: u8,
+    /// number of bits used for depth channel
+    pub depth_bits: u8,
+    /// number of bits used for stencil buffer
+    pub stencil_bits: u8,
+    /// is stereoscopy enabled
+    pub stereoscopy: bool,
+    /// is double buffering enabled
+    pub double_buffer: bool,
+    /// number of samples used for multisampling if enabled
+    pub multisampling: Option<u16>,
+    /// is srgb enabled
+    pub srgb: bool,
+}
+
+/// Trait that describes objects that have an OpenGL context
+/// and can be used to render upon
+pub trait EGLGraphicsBackend: GraphicsBackend {
+    /// Swaps buffers at the end of a frame.
+    fn swap_buffers(&self) -> ::std::result::Result<(), SwapBuffersError>;
+
+    /// Returns the address of an OpenGL function.
+    ///
+    /// Supposes that the context has been made current before this function is called.
+    unsafe fn get_proc_address(&self, symbol: &str) -> *const c_void;
+
+    /// Returns the dimensions of the window, or screen, etc in points.
+    ///
+    /// That are the scaled pixels of the underlying graphics backend.
+    /// For nested compositors this will respect the scaling of the root compositor.
+    /// For drawing directly onto hardware this unit will be equal to actual pixels.
+    fn get_framebuffer_dimensions(&self) -> (u32, u32);
+
+    /// Returns true if the OpenGL context is the current one in the thread.
+    fn is_current(&self) -> bool;
+
+    /// Makes the OpenGL context the current context in the current thread.
+    ///
+    /// # Unsafety
+    ///
+    /// This function is marked unsafe, because the context cannot be made current
+    /// on multiple threads.
+    unsafe fn make_current(&self) -> ::std::result::Result<(), SwapBuffersError>;
+
+    /// Returns the pixel format of the main framebuffer of the context.
+    fn get_pixel_format(&self) -> PixelFormat;
+}

src/backend/graphics/egl/native.rs

@@ -0,0 +1,267 @@
+//! Type safe native types for safe context/surface creation
+
+use super::error::*;
+use super::ffi;
+#[cfg(feature = "backend_drm")]
+use backend::drm::error::{Error as DrmError, ErrorKind as DrmErrorKind, Result as DrmResult};
+#[cfg(feature = "backend_drm")]
+use gbm::{AsRaw, BufferObjectFlags, Device as GbmDevice, Format as GbmFormat, Surface as GbmSurface};
+#[cfg(feature = "backend_drm")]
+use std::marker::PhantomData;
+#[cfg(feature = "backend_drm")]
+use std::os::unix::io::AsRawFd;
+#[cfg(any(feature = "backend_drm", feature = "backend_winit"))]
+use std::ptr;
+#[cfg(feature = "backend_winit")]
+use wayland_client::egl as wegl;
+#[cfg(feature = "backend_winit")]
+use winit::Window as WinitWindow;
+#[cfg(feature = "backend_winit")]
+use winit::os::unix::WindowExt;
+
+/// Trait for typed backend variants (X11/Wayland/GBM)
+pub trait Backend {
+    /// Surface type created by this backend
+    type Surface: NativeSurface;
+
+    /// Return an `EGLDisplay` based on this backend
+    ///
+    /// # Unsafety
+    ///
+    /// The returned `EGLDisplay` needs to be a valid ptr for egl,
+    /// but there is no way to test that.
+    unsafe fn get_display<F: Fn(&str) -> bool>(
+        display: ffi::NativeDisplayType, has_dp_extension: F, log: ::slog::Logger
+    ) -> ffi::egl::types::EGLDisplay;
+}
+
+#[cfg(feature = "backend_winit")]
+/// Wayland backend type
+pub enum Wayland {}
+#[cfg(feature = "backend_winit")]
+impl Backend for Wayland {
+    type Surface = wegl::WlEglSurface;
+
+    unsafe fn get_display<F>(
+        display: ffi::NativeDisplayType, has_dp_extension: F, log: ::slog::Logger
+    ) -> ffi::egl::types::EGLDisplay
+    where
+        F: Fn(&str) -> bool,
+    {
+        if has_dp_extension("EGL_KHR_platform_wayland") && ffi::egl::GetPlatformDisplay::is_loaded() {
+            trace!(
+                log,
+                "EGL Display Initialization via EGL_KHR_platform_wayland"
+            );
+            ffi::egl::GetPlatformDisplay(
+                ffi::egl::PLATFORM_WAYLAND_KHR,
+                display as *mut _,
+                ptr::null(),
+            )
+        } else if has_dp_extension("EGL_EXT_platform_wayland") && ffi::egl::GetPlatformDisplayEXT::is_loaded()
+        {
+            trace!(
+                log,
+                "EGL Display Initialization via EGL_EXT_platform_wayland"
+            );
+            ffi::egl::GetPlatformDisplayEXT(
+                ffi::egl::PLATFORM_WAYLAND_EXT,
+                display as *mut _,
+                ptr::null(),
+            )
+        } else {
+            trace!(log, "Default EGL Display Initialization via GetDisplay");
+            ffi::egl::GetDisplay(display as *mut _)
+        }
+    }
+}
+
+#[cfg(feature = "backend_winit")]
+/// Typed Xlib window for the `X11` backend
+pub struct XlibWindow(u64);
+#[cfg(feature = "backend_winit")]
+/// X11 backend type
+pub enum X11 {}
+#[cfg(feature = "backend_winit")]
+impl Backend for X11 {
+    type Surface = XlibWindow;
+
+    unsafe fn get_display<F>(
+        display: ffi::NativeDisplayType, has_dp_extension: F, log: ::slog::Logger
+    ) -> ffi::egl::types::EGLDisplay
+    where
+        F: Fn(&str) -> bool,
+    {
+        if has_dp_extension("EGL_KHR_platform_x11") && ffi::egl::GetPlatformDisplay::is_loaded() {
+            trace!(log, "EGL Display Initialization via EGL_KHR_platform_x11");
+            ffi::egl::GetPlatformDisplay(ffi::egl::PLATFORM_X11_KHR, display as *mut _, ptr::null())
+        } else if has_dp_extension("EGL_EXT_platform_x11") && ffi::egl::GetPlatformDisplayEXT::is_loaded() {
+            trace!(log, "EGL Display Initialization via EGL_EXT_platform_x11");
+            ffi::egl::GetPlatformDisplayEXT(ffi::egl::PLATFORM_X11_EXT, display as *mut _, ptr::null())
+        } else {
+            trace!(log, "Default EGL Display Initialization via GetDisplay");
+            ffi::egl::GetDisplay(display as *mut _)
+        }
+    }
+}
+#[cfg(feature = "backend_drm")]
+/// Gbm backend type
+pub struct Gbm<T: 'static> {
+    _userdata: PhantomData<T>,
+}
+#[cfg(feature = "backend_drm")]
+impl<T: 'static> Backend for Gbm<T> {
+    type Surface = GbmSurface<T>;
+
+    unsafe fn get_display<F>(
+        display: ffi::NativeDisplayType, has_dp_extension: F, log: ::slog::Logger
+    ) -> ffi::egl::types::EGLDisplay
+    where
+        F: Fn(&str) -> bool,
+    {
+        if has_dp_extension("EGL_KHR_platform_gbm") && ffi::egl::GetPlatformDisplay::is_loaded() {
+            trace!(log, "EGL Display Initialization via EGL_KHR_platform_gbm");
+            ffi::egl::GetPlatformDisplay(ffi::egl::PLATFORM_GBM_KHR, display as *mut _, ptr::null())
+        } else if has_dp_extension("EGL_MESA_platform_gbm") && ffi::egl::GetPlatformDisplayEXT::is_loaded() {
+            trace!(log, "EGL Display Initialization via EGL_MESA_platform_gbm");
+            ffi::egl::GetPlatformDisplayEXT(ffi::egl::PLATFORM_GBM_MESA, display as *mut _, ptr::null())
+        } else if has_dp_extension("EGL_MESA_platform_gbm") && ffi::egl::GetPlatformDisplay::is_loaded() {
+            trace!(log, "EGL Display Initialization via EGL_MESA_platform_gbm");
+            ffi::egl::GetPlatformDisplay(ffi::egl::PLATFORM_GBM_MESA, display as *mut _, ptr::null())
+        } else {
+            trace!(log, "Default EGL Display Initialization via GetDisplay");
+            ffi::egl::GetDisplay(display as *mut _)
+        }
+    }
+}
+
+/// Trait for types returning Surfaces which can be used to initialize `EGLSurface`s
+///
+/// ## Unsafety
+///
+/// The returned `NativeDisplayType` must be valid for egl and there is no way to test that.
+pub unsafe trait NativeDisplay<B: Backend> {
+    /// Arguments used to surface creation.
+    type Arguments;
+    /// Error type thrown by the surface creation in case of failure.
+    type Error: ::std::error::Error + Send + 'static;
+    /// Because one typ might implement multiple `Backend` this function must be called to check
+    /// if the expected `Backend` is used at runtime.
+    fn is_backend(&self) -> bool;
+    /// Return a raw pointer egl will accept for context creation.
+    fn ptr(&self) -> Result<ffi::NativeDisplayType>;
+    /// Create a surface
+    fn create_surface(&self, args: Self::Arguments) -> ::std::result::Result<B::Surface, Self::Error>;
+}
+
+#[cfg(feature = "backend_winit")]
+unsafe impl NativeDisplay<X11> for WinitWindow {
+    type Arguments = ();
+    type Error = Error;
+
+    fn is_backend(&self) -> bool {
+        self.get_xlib_display().is_some()
+    }
+
+    fn ptr(&self) -> Result<ffi::NativeDisplayType> {
+        self.get_xlib_display()
+            .map(|ptr| ptr as *const _)
+            .ok_or(ErrorKind::NonMatchingBackend("X11").into())
+    }
+
+    fn create_surface(&self, _args: ()) -> Result<XlibWindow> {
+        self.get_xlib_window()
+            .map(|ptr| XlibWindow(ptr))
+            .ok_or(ErrorKind::NonMatchingBackend("X11").into())
+    }
+}
+
+#[cfg(feature = "backend_winit")]
+unsafe impl NativeDisplay<Wayland> for WinitWindow {
+    type Arguments = ();
+    type Error = Error;
+
+    fn is_backend(&self) -> bool {
+        self.get_wayland_display().is_some()
+    }
+
+    fn ptr(&self) -> Result<ffi::NativeDisplayType> {
+        self.get_wayland_display()
+            .map(|ptr| ptr as *const _)
+            .ok_or(ErrorKind::NonMatchingBackend("Wayland").into())
+    }
+
+    fn create_surface(&self, _args: ()) -> Result<wegl::WlEglSurface> {
+        if let Some(surface) = self.get_wayland_surface() {
+            let (w, h) = self.get_inner_size().unwrap();
+            Ok(unsafe { wegl::WlEglSurface::new_from_raw(surface as *mut _, w as i32, h as i32) })
+        } else {
+            bail!(ErrorKind::NonMatchingBackend("Wayland"))
+        }
+    }
+}
+
+#[cfg(feature = "backend_drm")]
+/// Arguments necessary to construct a `GbmSurface`
+pub struct GbmSurfaceArguments {
+    /// Size of the surface
+    pub size: (u32, u32),
+    /// Pixel format of the surface
+    pub format: GbmFormat,
+    /// Flags for surface creation
+    pub flags: BufferObjectFlags,
+}
+
+#[cfg(feature = "backend_drm")]
+unsafe impl<A: AsRawFd + 'static, T: 'static> NativeDisplay<Gbm<T>> for GbmDevice<A> {
+    type Arguments = GbmSurfaceArguments;
+    type Error = DrmError;
+
+    fn is_backend(&self) -> bool {
+        true
+    }
+
+    fn ptr(&self) -> Result<ffi::NativeDisplayType> {
+        Ok(self.as_raw() as *const _)
+    }
+
+    fn create_surface(&self, args: GbmSurfaceArguments) -> DrmResult<GbmSurface<T>> {
+        use backend::drm::error::ResultExt as DrmResultExt;
+
+        DrmResultExt::chain_err(
+            GbmDevice::create_surface(self, args.size.0, args.size.1, args.format, args.flags),
+            || DrmErrorKind::GbmInitFailed,
+        )
+    }
+}
+
+/// Trait for types returning valid surface pointers for initializing egl
+///
+/// ## Unsafety
+///
+/// The returned `NativeWindowType` must be valid for egl and there is no way to test that.
+pub unsafe trait NativeSurface {
+    /// Return a raw pointer egl will accept for surface creation.
+    fn ptr(&self) -> ffi::NativeWindowType;
+}
+
+#[cfg(feature = "backend_winit")]
+unsafe impl NativeSurface for XlibWindow {
+    fn ptr(&self) -> ffi::NativeWindowType {
+        self.0 as *const _
+    }
+}
+
+#[cfg(feature = "backend_winit")]
+unsafe impl NativeSurface for wegl::WlEglSurface {
+    fn ptr(&self) -> ffi::NativeWindowType {
+        self.ptr() as *const _
+    }
+}
+
+#[cfg(feature = "backend_drm")]
+unsafe impl<T: 'static> NativeSurface for GbmSurface<T> {
+    fn ptr(&self) -> ffi::NativeWindowType {
+        self.as_raw() as *const _
+    }
+}

src/backend/graphics/egl/surface.rs

@@ -0,0 +1,123 @@
+//! EGL surface related structs
+
+use super::{EGLContext, SwapBuffersError};
+use super::error::*;
+use super::ffi;
+use super::native;
+use std::ops::{Deref, DerefMut};
+use std::rc::{Rc, Weak};
+
+/// EGL surface of a given egl context for rendering
+pub struct EGLSurface<N: native::NativeSurface> {
+    context: Weak<ffi::egl::types::EGLContext>,
+    display: Weak<ffi::egl::types::EGLDisplay>,
+    native: N,
+    surface: ffi::egl::types::EGLSurface,
+}
+
+impl<N: native::NativeSurface> Deref for EGLSurface<N> {
+    type Target = N;
+    fn deref(&self) -> &N {
+        &self.native
+    }
+}
+
+impl<N: native::NativeSurface> DerefMut for EGLSurface<N> {
+    fn deref_mut(&mut self) -> &mut N {
+        &mut self.native
+    }
+}
+
+impl<N: native::NativeSurface> EGLSurface<N> {
+    pub(crate) fn new<B: native::Backend<Surface = N>, D: native::NativeDisplay<B>>(
+        context: &EGLContext<B, D>, native: N
+    ) -> Result<EGLSurface<N>> {
+        let surface = unsafe {
+            ffi::egl::CreateWindowSurface(
+                *context.display,
+                context.config_id,
+                native.ptr(),
+                context.surface_attributes.as_ptr(),
+            )
+        };
+
+        if surface.is_null() {
+            bail!(ErrorKind::SurfaceCreationFailed);
+        }
+
+        Ok(EGLSurface {
+            context: Rc::downgrade(&context.context),
+            display: Rc::downgrade(&context.display),
+            native,
+            surface,
+        })
+    }
+
+    /// Swaps buffers at the end of a frame.
+    pub fn swap_buffers(&self) -> ::std::result::Result<(), SwapBuffersError> {
+        if let Some(display) = self.display.upgrade() {
+            let ret = unsafe { ffi::egl::SwapBuffers((*display) as *const _, self.surface as *const _) };
+
+            if ret == 0 {
+                match unsafe { ffi::egl::GetError() } as u32 {
+                    ffi::egl::CONTEXT_LOST => Err(SwapBuffersError::ContextLost),
+                    err => Err(SwapBuffersError::Unknown(err)),
+                }
+            } else {
+                Ok(())
+            }
+        } else {
+            Err(SwapBuffersError::ContextLost)
+        }
+    }
+
+    /// Makes the OpenGL context the current context in the current thread.
+    ///
+    /// # Unsafety
+    ///
+    /// This function is marked unsafe, because the context cannot be made current
+    /// on multiple threads.
+    pub unsafe fn make_current(&self) -> ::std::result::Result<(), SwapBuffersError> {
+        if let (Some(display), Some(context)) = (self.display.upgrade(), self.context.upgrade()) {
+            let ret = ffi::egl::MakeCurrent(
+                (*display) as *const _,
+                self.surface as *const _,
+                self.surface as *const _,
+                (*context) as *const _,
+            );
+
+            if ret == 0 {
+                match ffi::egl::GetError() as u32 {
+                    ffi::egl::CONTEXT_LOST => Err(SwapBuffersError::ContextLost),
+                    err => panic!("eglMakeCurrent failed (eglGetError returned 0x{:x})", err),
+                }
+            } else {
+                Ok(())
+            }
+        } else {
+            Err(SwapBuffersError::ContextLost)
+        }
+    }
+
+    /// Returns true if the OpenGL surface is the current one in the thread.
+    pub fn is_current(&self) -> bool {
+        if self.context.upgrade().is_some() {
+            unsafe {
+                ffi::egl::GetCurrentSurface(ffi::egl::DRAW as _) == self.surface as *const _
+                    && ffi::egl::GetCurrentSurface(ffi::egl::READ as _) == self.surface as *const _
+            }
+        } else {
+            false
+        }
+    }
+}
+
+impl<N: native::NativeSurface> Drop for EGLSurface<N> {
+    fn drop(&mut self) {
+        if let Some(display) = self.display.upgrade() {
+            unsafe {
+                ffi::egl::DestroySurface((*display) as *const _, self.surface as *const _);
+            }
+        }
+    }
+}

src/backend/graphics/egl/wayland.rs

@@ -0,0 +1,403 @@
+//! Wayland specific EGL functionality - EGL based `WlBuffer`s.
+//!
+//! The types of this module can be used to initialize hardware acceleration rendering
+//! based on EGL for clients as it may enabled usage of `EGLImage` based `WlBuffer`s.
+//!
+//! To use it bind any backend implementing the `EGLWaylandExtensions` trait, that shall do the
+//! rendering (so pick a fast one), to the `wayland_server::Display` of your compositor.
+//! Note only one backend may be bould to any `Display` at any time.
+//!
+//! You may then use the resulting `EGLDisplay` to recieve `EGLImages` of an egl-based `WlBuffer`
+//! for rendering.
+
+use backend::graphics::egl::{ffi, native, EGLContext, EglExtensionNotSupportedError};
+use backend::graphics::egl::error::*;
+use backend::graphics::egl::ffi::egl::types::EGLImage;
+use nix::libc::c_uint;
+use std::fmt;
+use std::rc::{Rc, Weak};
+use wayland_server::{Display, Resource};
+use wayland_server::protocol::wl_buffer::WlBuffer;
+use wayland_sys::server::wl_display;
+
+/// Error that can occur when accessing an EGL buffer
+pub enum BufferAccessError {
+    /// The corresponding Context is not alive anymore
+    ContextLost,
+    /// This buffer is not managed by the EGL buffer
+    NotManaged(WlBuffer),
+    /// Failed to create EGLImages from the buffer
+    EGLImageCreationFailed,
+    /// The required EGL extension is not supported by the underlying EGL implementation
+    EglExtensionNotSupported(EglExtensionNotSupportedError),
+}
+
+impl fmt::Debug for BufferAccessError {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> ::std::result::Result<(), fmt::Error> {
+        match *self {
+            BufferAccessError::ContextLost => write!(formatter, "BufferAccessError::ContextLost"),
+            BufferAccessError::NotManaged(_) => write!(formatter, "BufferAccessError::NotManaged"),
+            BufferAccessError::EGLImageCreationFailed => {
+                write!(formatter, "BufferAccessError::EGLImageCreationFailed")
+            }
+            BufferAccessError::EglExtensionNotSupported(ref err) => write!(formatter, "{:?}", err),
+        }
+    }
+}
+
+impl fmt::Display for BufferAccessError {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> ::std::result::Result<(), fmt::Error> {
+        use std::error::Error;
+        match *self {
+            BufferAccessError::ContextLost
+            | BufferAccessError::NotManaged(_)
+            | BufferAccessError::EGLImageCreationFailed => write!(formatter, "{}", self.description()),
+            BufferAccessError::EglExtensionNotSupported(ref err) => err.fmt(formatter),
+        }
+    }
+}
+
+impl ::std::error::Error for BufferAccessError {
+    fn description(&self) -> &str {
+        match *self {
+            BufferAccessError::ContextLost => "The corresponding context was lost",
+            BufferAccessError::NotManaged(_) => "This buffer is not mananged by EGL",
+            BufferAccessError::EGLImageCreationFailed => "Failed to create EGLImages from the buffer",
+            BufferAccessError::EglExtensionNotSupported(ref err) => err.description(),
+        }
+    }
+
+    fn cause(&self) -> Option<&::std::error::Error> {
+        match *self {
+            BufferAccessError::EglExtensionNotSupported(ref err) => Some(err),
+            _ => None,
+        }
+    }
+}
+
+impl From<EglExtensionNotSupportedError> for BufferAccessError {
+    fn from(error: EglExtensionNotSupportedError) -> Self {
+        BufferAccessError::EglExtensionNotSupported(error)
+    }
+}
+
+/// Error that might happen when binding an `EGLImage` to a gl texture
+#[derive(Debug, Clone, PartialEq)]
+pub enum TextureCreationError {
+    /// The given plane index is out of bounds
+    PlaneIndexOutOfBounds,
+    /// The OpenGL context has been lost and needs to be recreated.
+    ///
+    /// All the objects associated to it (textures, buffers, programs, etc.)
+    /// need to be recreated from scratch.
+    ///
+    /// Operations will have no effect. Functions that read textures, buffers, etc.
+    /// from OpenGL will return uninitialized data instead.
+    ///
+    /// A context loss usually happens on mobile devices when the user puts the
+    /// application on sleep and wakes it up later. However any OpenGL implementation
+    /// can theoretically lose the context at any time.
+    ContextLost,
+    /// Failed to bind the EGLImage to the given texture
+    ///
+    /// The given argument is the gl error code
+    TextureBindingFailed(u32),
+}
+
+impl fmt::Display for TextureCreationError {
+    fn fmt(&self, formatter: &mut fmt::Formatter) -> ::std::result::Result<(), fmt::Error> {
+        use std::error::Error;
+        match *self {
+            TextureCreationError::ContextLost => write!(formatter, "{}", self.description()),
+            TextureCreationError::PlaneIndexOutOfBounds => write!(formatter, "{}", self.description()),
+            TextureCreationError::TextureBindingFailed(code) => write!(
+                formatter,
+                "{}. Gl error code: {:?}",
+                self.description(),
+                code
+            ),
+        }
+    }
+}
+
+impl ::std::error::Error for TextureCreationError {
+    fn description(&self) -> &str {
+        match *self {
+            TextureCreationError::ContextLost => "The context has been lost, it needs to be recreated",
+            TextureCreationError::PlaneIndexOutOfBounds => "This buffer is not mananged by EGL",
+            TextureCreationError::TextureBindingFailed(_) => "Failed to create EGLImages from the buffer",
+        }
+    }
+
+    fn cause(&self) -> Option<&::std::error::Error> {
+        None
+    }
+}
+
+/// Texture format types
+#[repr(i32)]
+#[allow(non_camel_case_types)]
+pub enum Format {
+    /// RGB format
+    RGB = ffi::egl::TEXTURE_RGB as i32,
+    /// RGB + alpha channel format
+    RGBA = ffi::egl::TEXTURE_RGBA as i32,
+    /// External format
+    External = ffi::egl::TEXTURE_EXTERNAL_WL,
+    /// 2-plane Y and UV format
+    Y_UV = ffi::egl::TEXTURE_Y_UV_WL,
+    /// 3-plane Y, U and V format
+    Y_U_V = ffi::egl::TEXTURE_Y_U_V_WL,
+    /// 2-plane Y and XUXV format
+    Y_XUXV = ffi::egl::TEXTURE_Y_XUXV_WL,
+}
+
+impl Format {
+    /// Amount of planes this format uses
+    pub fn num_planes(&self) -> usize {
+        match *self {
+            Format::RGB | Format::RGBA | Format::External => 1,
+            Format::Y_UV | Format::Y_XUXV => 2,
+            Format::Y_U_V => 3,
+        }
+    }
+}
+
+/// Images of the egl-based `WlBuffer`.
+pub struct EGLImages {
+    display: Weak<ffi::egl::types::EGLDisplay>,
+    /// Width in pixels
+    pub width: u32,
+    /// Height in pixels
+    pub height: u32,
+    /// If the y-axis is inverted or not
+    pub y_inverted: bool,
+    /// Format of these images
+    pub format: Format,
+    images: Vec<EGLImage>,
+    buffer: WlBuffer,
+}
+
+impl EGLImages {
+    /// Amount of planes of these `EGLImages`
+    pub fn num_planes(&self) -> usize {
+        self.format.num_planes()
+    }
+
+    /// Bind plane to an OpenGL texture id
+    ///
+    /// This does only temporarily modify the OpenGL state any changes are reverted before returning.
+    ///
+    /// # Unsafety
+    ///
+    /// The given `tex_id` needs to be a valid GL texture otherwise undefined behavior might occur.
+    pub unsafe fn bind_to_texture(
+        &self, plane: usize, tex_id: c_uint
+    ) -> ::std::result::Result<(), TextureCreationError> {
+        if self.display.upgrade().is_some() {
+            let mut old_tex_id: i32 = 0;
+            ffi::gl::GetIntegerv(ffi::gl::TEXTURE_BINDING_2D, &mut old_tex_id);
+            ffi::gl::BindTexture(ffi::gl::TEXTURE_2D, tex_id);
+            ffi::gl::EGLImageTargetTexture2DOES(
+                ffi::gl::TEXTURE_2D,
+                *self.images
+                    .get(plane)
+                    .ok_or(TextureCreationError::PlaneIndexOutOfBounds)?,
+            );
+            let res = match ffi::egl::GetError() as u32 {
+                ffi::egl::SUCCESS => Ok(()),
+                err => Err(TextureCreationError::TextureBindingFailed(err)),
+            };
+            ffi::gl::BindTexture(ffi::gl::TEXTURE_2D, old_tex_id as u32);
+            res
+        } else {
+            Err(TextureCreationError::ContextLost)
+        }
+    }
+}
+
+impl Drop for EGLImages {
+    fn drop(&mut self) {
+        if let Some(display) = self.display.upgrade() {
+            for image in self.images.drain(..) {
+                unsafe {
+                    ffi::egl::DestroyImageKHR(*display, image);
+                }
+            }
+        }
+        self.buffer.release();
+    }
+}
+
+/// Trait any backend type may implement that allows binding a `wayland_server::Display`
+/// to create an `EGLDisplay` for egl-based `WlBuffer`s.
+pub trait EGLWaylandExtensions {
+    /// Binds this EGL context to the given Wayland display.
+    ///
+    /// This will allow clients to utilize EGL to create hardware-accelerated
+    /// surfaces. The server will need to be able to handle egl-wl_buffers.
+    /// See the `wayland::drm` module.
+    ///
+    /// ## Errors
+    ///
+    /// This might return `WlExtensionNotSupported` if binding is not supported
+    /// by the EGL implementation.
+    ///
+    /// This might return `OtherEGLDisplayAlreadyBound` if called for the same
+    /// `Display` multiple times, as only one context may be bound at any given time.
+    fn bind_wl_display(&self, display: &Display) -> Result<EGLDisplay>;
+}
+
+/// Type to recieve `EGLImages` for egl-based `WlBuffer`s.
+///
+/// Can be created by using `EGLWaylandExtensions::bind_wl_display`.
+pub struct EGLDisplay(Weak<ffi::egl::types::EGLDisplay>, *mut wl_display);
+
+impl EGLDisplay {
+    fn new<B: native::Backend, N: native::NativeDisplay<B>>(
+        context: &EGLContext<B, N>, display: *mut wl_display
+    ) -> EGLDisplay {
+        EGLDisplay(Rc::downgrade(&context.display), display)
+    }
+
+    /// Try to recieve `EGLImages` from a given `WlBuffer`.
+    ///
+    /// In case the buffer is not managed by egl (but e.g. the wayland::shm module)
+    /// a `BufferAccessError::NotManaged(WlBuffer)` is returned with the original buffer
+    /// to render it another way.
+    pub fn egl_buffer_contents(
+        &self, buffer: WlBuffer
+    ) -> ::std::result::Result<EGLImages, BufferAccessError> {
+        if let Some(display) = self.0.upgrade() {
+            let mut format: i32 = 0;
+            if unsafe {
+                ffi::egl::QueryWaylandBufferWL(
+                    *display,
+                    buffer.ptr() as *mut _,
+                    ffi::egl::EGL_TEXTURE_FORMAT,
+                    &mut format as *mut _,
+                ) == 0
+            } {
+                return Err(BufferAccessError::NotManaged(buffer));
+            }
+            let format = match format {
+                x if x == ffi::egl::TEXTURE_RGB as i32 => Format::RGB,
+                x if x == ffi::egl::TEXTURE_RGBA as i32 => Format::RGBA,
+                ffi::egl::TEXTURE_EXTERNAL_WL => Format::External,
+                ffi::egl::TEXTURE_Y_UV_WL => Format::Y_UV,
+                ffi::egl::TEXTURE_Y_U_V_WL => Format::Y_U_V,
+                ffi::egl::TEXTURE_Y_XUXV_WL => Format::Y_XUXV,
+                _ => panic!("EGL returned invalid texture type"),
+            };
+
+            let mut width: i32 = 0;
+            if unsafe {
+                ffi::egl::QueryWaylandBufferWL(
+                    *display,
+                    buffer.ptr() as *mut _,
+                    ffi::egl::WIDTH as i32,
+                    &mut width as *mut _,
+                ) == 0
+            } {
+                return Err(BufferAccessError::NotManaged(buffer));
+            }
+
+            let mut height: i32 = 0;
+            if unsafe {
+                ffi::egl::QueryWaylandBufferWL(
+                    *display,
+                    buffer.ptr() as *mut _,
+                    ffi::egl::HEIGHT as i32,
+                    &mut height as *mut _,
+                ) == 0
+            } {
+                return Err(BufferAccessError::NotManaged(buffer));
+            }
+
+            let mut inverted: i32 = 0;
+            if unsafe {
+                ffi::egl::QueryWaylandBufferWL(
+                    *display,
+                    buffer.ptr() as *mut _,
+                    ffi::egl::WAYLAND_Y_INVERTED_WL,
+                    &mut inverted as *mut _,
+                ) != 0
+            } {
+                inverted = 1;
+            }
+
+            let mut images = Vec::with_capacity(format.num_planes());
+            for i in 0..format.num_planes() {
+                let mut out = Vec::with_capacity(3);
+                out.push(ffi::egl::WAYLAND_PLANE_WL as i32);
+                out.push(i as i32);
+                out.push(ffi::egl::NONE as i32);
+
+                images.push({
+                    let image = unsafe {
+                        ffi::egl::CreateImageKHR(
+                            *display,
+                            ffi::egl::NO_CONTEXT,
+                            ffi::egl::WAYLAND_BUFFER_WL,
+                            buffer.ptr() as *mut _,
+                            out.as_ptr(),
+                        )
+                    };
+                    if image == ffi::egl::NO_IMAGE_KHR {
+                        return Err(BufferAccessError::EGLImageCreationFailed);
+                    } else {
+                        image
+                    }
+                });
+            }
+
+            Ok(EGLImages {
+                display: Rc::downgrade(&display),
+                width: width as u32,
+                height: height as u32,
+                y_inverted: inverted != 0,
+                format,
+                images,
+                buffer,
+            })
+        } else {
+            Err(BufferAccessError::ContextLost)
+        }
+    }
+}
+
+impl Drop for EGLDisplay {
+    fn drop(&mut self) {
+        if let Some(display) = self.0.upgrade() {
+            if !self.1.is_null() {
+                unsafe {
+                    ffi::egl::UnbindWaylandDisplayWL(*display, self.1 as *mut _);
+                }
+            }
+        }
+    }
+}
+
+impl<E: EGLWaylandExtensions> EGLWaylandExtensions for Rc<E> {
+    fn bind_wl_display(&self, display: &Display) -> Result<EGLDisplay> {
+        (**self).bind_wl_display(display)
+    }
+}
+
+impl<B: native::Backend, N: native::NativeDisplay<B>> EGLWaylandExtensions for EGLContext<B, N> {
+    fn bind_wl_display(&self, display: &Display) -> Result<EGLDisplay> {
+        if !self.wl_drm_support {
+            bail!(ErrorKind::EglExtensionNotSupported(&[
+                "EGL_WL_bind_wayland_display"
+            ]));
+        }
+        if !self.egl_to_texture_support {
+            bail!(ErrorKind::EglExtensionNotSupported(&["GL_OES_EGL_image"]));
+        }
+        let res = unsafe { ffi::egl::BindWaylandDisplayWL(*self.display, display.ptr() as *mut _) };
+        if res == 0 {
+            bail!(ErrorKind::OtherEGLDisplayAlreadyBound);
+        }
+        Ok(EGLDisplay::new(self, unsafe { display.ptr() }))
+    }
+}

src/backend/graphics/glium.rs

@@ -1,6 +1,8 @@
 //! Glium compatibility module
 
 use backend::graphics::egl::{EGLGraphicsBackend, SwapBuffersError};
+use backend::graphics::egl::error::Result as EGLResult;
+use backend::graphics::egl::wayland::{EGLDisplay, EGLWaylandExtensions};
 use glium::Frame;
 use glium::SwapBuffersError as GliumSwapBuffersError;
 use glium::backend::{Backend, Context, Facade};
@@ -8,6 +10,7 @@ use glium::debug::DebugCallbackBehavior;
 use std::borrow::Borrow;
 use std::os::raw::c_void;
 use std::rc::Rc;
+use wayland_server::Display;
 
 impl From<SwapBuffersError> for GliumSwapBuffersError {
     fn from(error: SwapBuffersError) -> Self {
@@ -73,6 +76,13 @@ impl<T: EGLGraphicsBackend + 'static> From<T> for GliumGraphicsBackend<T> {
     }
 }
 
+impl<T: EGLGraphicsBackend + EGLWaylandExtensions + 'static> EGLWaylandExtensions
+    for GliumGraphicsBackend<T> {
+    fn bind_wl_display(&self, display: &Display) -> EGLResult<EGLDisplay> {
+        (*self.backend).0.bind_wl_display(display)
+    }
+}
+
 unsafe impl<T: EGLGraphicsBackend> Backend for InternalBackend<T> {
     fn swap_buffers(&self) -> Result<(), GliumSwapBuffersError> {
         self.0.swap_buffers().map_err(Into::into)

src/backend/udev.rs

@@ -9,37 +9,48 @@
 //! See also `examples/udev.rs` for pure hardware backed example of a compositor utilizing this
 //! backend.
 
-use backend::drm::{drm_device_bind, DrmBackend, DrmDevice, DrmHandler};
+use backend::drm::{drm_device_bind, DrmDevice, DrmHandler};
 use backend::session::{Session, SessionObserver};
+use drm::Device as BasicDevice;
+use drm::control::Device as ControlDevice;
 use nix::fcntl;
-use nix::sys::stat::{dev_t, fstat};
-use std::borrow::Borrow;
+use nix::sys::stat::dev_t;
 use std::collections::HashMap;
 use std::ffi::OsString;
 use std::io::{Error as IoError, Result as IoResult};
 use std::mem::drop;
-use std::os::unix::io::AsRawFd;
+use std::os::unix::io::{AsRawFd, RawFd};
 use std::path::{Path, PathBuf};
 use udev::{Context, Enumerator, Event, EventType, MonitorBuilder, MonitorSocket, Result as UdevResult};
 use wayland_server::{EventLoopHandle, StateProxy, StateToken};
 use wayland_server::sources::{FdEventSource, FdEventSourceImpl, FdInterest};
 
+/// Udev's `DrmDevice` type based on the underlying session
+pub struct SessionFdDrmDevice(RawFd);
+
+impl AsRawFd for SessionFdDrmDevice {
+    fn as_raw_fd(&self) -> RawFd {
+        self.0
+    }
+}
+impl BasicDevice for SessionFdDrmDevice {}
+impl ControlDevice for SessionFdDrmDevice {}
+
 /// Graphical backend that monitors available drm devices.
 ///
 /// Provides a way to automatically initialize a `DrmDevice` for available gpus and notifies the
 /// given handler of any changes. Can be used to provide hot-plug functionality for gpus and
 /// attached monitors.
 pub struct UdevBackend<
-    B: Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
+    H: DrmHandler<SessionFdDrmDevice> + 'static,
     S: Session + 'static,
-    T: UdevHandler<B, H> + 'static,
+    T: UdevHandler<H> + 'static,
 > {
     devices: HashMap<
         dev_t,
         (
-            StateToken<DrmDevice<B>>,
-            FdEventSource<(StateToken<DrmDevice<B>>, H)>,
+            StateToken<DrmDevice<SessionFdDrmDevice>>,
+            FdEventSource<(StateToken<DrmDevice<SessionFdDrmDevice>>, H)>,
         ),
     >,
     monitor: MonitorSocket,
@@ -48,12 +59,8 @@ pub struct UdevBackend<
     logger: ::slog::Logger,
 }
 
-impl<
-    B: From<DrmBackend> + Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
-    S: Session + 'static,
-    T: UdevHandler<B, H> + 'static,
-> UdevBackend<B, H, S, T> {
+impl<H: DrmHandler<SessionFdDrmDevice> + 'static, S: Session + 'static, T: UdevHandler<H> + 'static>
+    UdevBackend<H, S, T> {
     /// Creates a new `UdevBackend` and adds it to the given `EventLoop`'s state.
     ///
     /// ## Arguments
@@ -64,7 +71,7 @@ impl<
     /// `logger`  - slog Logger to be used by the backend and its `DrmDevices`.
     pub fn new<'a, L>(
         mut evlh: &mut EventLoopHandle, context: &Context, mut session: S, mut handler: T, logger: L
-    ) -> Result<StateToken<UdevBackend<B, H, S, T>>>
+    ) -> Result<StateToken<UdevBackend<H, S, T>>>
     where
         L: Into<Option<::slog::Logger>>,
     {
@@ -75,43 +82,29 @@ impl<
             .into_iter()
             // Create devices
             .flat_map(|path| {
-                match unsafe { DrmDevice::new_from_fd(
+                match DrmDevice::new(
                     {
                         match session.open(&path, fcntl::O_RDWR | fcntl::O_CLOEXEC | fcntl::O_NOCTTY | fcntl::O_NONBLOCK) {
-                            Ok(fd) => fd,
+                            Ok(fd) => SessionFdDrmDevice(fd),
                             Err(err) => {
                                 warn!(logger, "Unable to open drm device {:?}, Error: {:?}. Skipping", path, err);
                                 return None;
                             }
                         }
                     }, logger.clone()
-                ) } {
+                ) {
                     // Call the handler, which might add it to the runloop
-                    Ok(mut device) => match handler.device_added(&mut evlh.state().as_proxy(), &mut device) {
-                        // fstat them
-                        Some(drm_handler) => match fstat(device.as_raw_fd()) {
-                            Ok(stat) => {
+                    Ok(mut device) => {
+                        let fd = device.as_raw_fd();
+                        let devnum = device.device_id();
+                        match handler.device_added(&mut evlh.state().as_proxy(), &mut device) {
+                            Some(drm_handler) => {
                                 let token = evlh.state().insert(device);
                                 if let Ok(event_source) = drm_device_bind(&mut evlh, token.clone(), drm_handler) {
-                                    Some((stat.st_rdev, (token, event_source)))
+                                    Some((devnum, (token, event_source)))
                                 } else {
                                     handler.device_removed(evlh.state(), &token);
                                     let device = evlh.state().remove(token);
-                                    let fd = device.as_raw_fd();
-                                    drop(device);
-                                    if let Err(err) = session.close(fd) {
-                                        warn!(logger, "Failed to close dropped device. Error: {:?}. Ignoring", err);
-                                    };
-                                    None
-                                }
-                            },
-                            Err(err) => {
-                                // almost impossible to hit, but lets do it as good as possible
-                                error!(logger, "Failed to get devnum of newly initialized device, dropping. Error: {:?}", err);
-                                let token = evlh.state().insert(device);
-                                handler.device_removed(evlh.state(), &token);
-                                let device = evlh.state().remove(token);
-                                let fd = device.as_raw_fd();
                                     drop(device);
                                     if let Err(err) = session.close(fd) {
                                         warn!(logger, "Failed to close dropped device. Error: {:?}. Ignoring", err);
@@ -120,21 +113,21 @@ impl<
                                 }
                             },
                             None => {
-                            let fd = device.as_raw_fd();
                                 drop(device); //drops master
                                 if let Err(err) = session.close(fd) {
                                     warn!(logger, "Failed to close device. Error: {:?}. Ignoring", err);
                                 }
                                 None
                             }
+                        }
                     },
                     Err(err) => {
                         warn!(logger, "Failed to initialize device {:?}. Error: {:?}. Skipping", path, err);
-                        return None;
+                        None
                     }
                 }
             })
-            .collect::<HashMap<dev_t, (StateToken<DrmDevice<B>>, FdEventSource<(StateToken<DrmDevice<B>>, H)>)>>();
+            .collect::<HashMap<dev_t, (StateToken<DrmDevice<SessionFdDrmDevice>>, FdEventSource<(StateToken<DrmDevice<SessionFdDrmDevice>>, H)>)>>();
 
         let mut builder = MonitorBuilder::new(context).chain_err(|| ErrorKind::FailedToInitMonitor)?;
         builder
@@ -181,11 +174,10 @@ impl<
 }
 
 impl<
-    B: Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
+    H: DrmHandler<SessionFdDrmDevice> + 'static,
     S: Session + 'static,
-    T: UdevHandler<B, H> + 'static,
-> SessionObserver for StateToken<UdevBackend<B, H, S, T>> {
+    T: UdevHandler<H> + 'static,
+> SessionObserver for StateToken<UdevBackend<H, S, T>> {
     fn pause<'a>(&mut self, state: &mut StateProxy<'a>) {
         state.with_value(self, |state, udev| {
             for &mut (ref mut device, _) in udev.devices.values_mut() {
@@ -207,24 +199,22 @@ impl<
 ///
 /// Allows the backend to recieve kernel events and thus to drive the `UdevHandler`.
 /// No runtime functionality can be provided without using this function.
-pub fn udev_backend_bind<B, S, H, T>(
-    evlh: &mut EventLoopHandle, udev: StateToken<UdevBackend<B, H, S, T>>
-) -> IoResult<FdEventSource<StateToken<UdevBackend<B, H, S, T>>>>
+pub fn udev_backend_bind<S, H, T>(
+    evlh: &mut EventLoopHandle, udev: StateToken<UdevBackend<H, S, T>>
+) -> IoResult<FdEventSource<StateToken<UdevBackend<H, S, T>>>>
 where
-    B: From<DrmBackend> + Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
-    T: UdevHandler<B, H> + 'static,
+    H: DrmHandler<SessionFdDrmDevice> + 'static,
+    T: UdevHandler<H> + 'static,
     S: Session + 'static,
 {
     let fd = evlh.state().get(&udev).monitor.as_raw_fd();
     evlh.add_fd_event_source(fd, fd_event_source_implementation(), udev, FdInterest::READ)
 }
 
-fn fd_event_source_implementation<B, S, H, T>() -> FdEventSourceImpl<StateToken<UdevBackend<B, H, S, T>>>
+fn fd_event_source_implementation<S, H, T>() -> FdEventSourceImpl<StateToken<UdevBackend<H, S, T>>>
 where
-    B: From<DrmBackend> + Borrow<DrmBackend> + 'static,
-    H: DrmHandler<B> + 'static,
-    T: UdevHandler<B, H> + 'static,
+    H: DrmHandler<SessionFdDrmDevice> + 'static,
+    T: UdevHandler<H> + 'static,
     S: Session + 'static,
 {
     FdEventSourceImpl {
@@ -241,8 +231,7 @@ where
                         info!(evlh.state().get(token).logger, "Device Added");
                         if let (Some(path), Some(devnum)) = (event.devnode(), event.devnum()) {
                             let mut device = {
-                                match unsafe {
-                                    DrmDevice::new_from_fd(
+                                match DrmDevice::new(
                                     {
                                         let logger = evlh.state().get(token).logger.clone();
                                         match evlh.state().get_mut(token).session.open(
@@ -250,16 +239,20 @@ where
                                             fcntl::O_RDWR | fcntl::O_CLOEXEC | fcntl::O_NOCTTY
                                                 | fcntl::O_NONBLOCK,
                                         ) {
-                                                Ok(fd) => fd,
+                                            Ok(fd) => SessionFdDrmDevice(fd),
                                             Err(err) => {
-                                                    warn!(logger, "Unable to open drm device {:?}, Error: {:?}. Skipping", path, err);
+                                                warn!(
+                                                    logger,
+                                                    "Unable to open drm device {:?}, Error: {:?}. Skipping",
+                                                    path,
+                                                    err
+                                                );
                                                 continue;
                                             }
                                         }
                                     },
                                     evlh.state().get(token).logger.clone(),
-                                    )
-                                } {
+                                ) {
                                     Ok(dev) => dev,
                                     Err(err) => {
                                         warn!(
@@ -272,6 +265,7 @@ where
                                     }
                                 }
                             };
+                            let fd = device.as_raw_fd();
                             match evlh.state().with_value(token, |state, udev| {
                                 udev.handler.device_added(state, &mut device)
                             }) {
@@ -289,7 +283,6 @@ where
                                             let mut state: StateProxy = state.into();
                                             udev.handler.device_removed(&mut state, &dev_token);
                                             let device = state.remove(dev_token);
-                                            let fd = device.as_raw_fd();
                                             drop(device);
                                             if let Err(err) = udev.session.close(fd) {
                                                 warn!(
@@ -302,7 +295,6 @@ where
                                     }
                                 }
                                 None => {
-                                    let fd = device.as_raw_fd();
                                     drop(device);
                                     evlh.state().with_value(token, |_state, udev| {
                                         if let Err(err) = udev.session.close(fd) {
@@ -365,16 +357,16 @@ where
 }
 
 /// Handler for the `UdevBackend`, allows to open, close and update drm devices as they change during runtime.
-pub trait UdevHandler<B: Borrow<DrmBackend> + 'static, H: DrmHandler<B> + 'static>
-     {
+pub trait UdevHandler<H: DrmHandler<SessionFdDrmDevice> + 'static> {
     /// Called on initialization for every known device and when a new device is detected.
     ///
     /// Returning a `DrmHandler` will initialize the device, returning `None` will ignore the device.
     ///
     /// ## Panics
     /// Panics if you try to borrow the token of the belonging `UdevBackend` using this `StateProxy`.
-    fn device_added<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &mut DrmDevice<B>)
-        -> Option<H>;
+    fn device_added<'a, S: Into<StateProxy<'a>>>(
+        &mut self, state: S, device: &mut DrmDevice<SessionFdDrmDevice>
+    ) -> Option<H>;
     /// Called when an open device is changed.
     ///
     /// This usually indicates that some connectors did become available or were unplugged. The handler
@@ -382,7 +374,9 @@ pub trait UdevHandler<B: Borrow<DrmBackend> + 'static, H: DrmHandler<B> + 'stati
     ///
     /// ## Panics
     /// Panics if you try to borrow the token of the belonging `UdevBackend` using this `StateProxy`.
-    fn device_changed<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &StateToken<DrmDevice<B>>);
+    fn device_changed<'a, S: Into<StateProxy<'a>>>(
+        &mut self, state: S, device: &StateToken<DrmDevice<SessionFdDrmDevice>>
+    );
     /// Called when a device was removed.
     ///
     /// The device will not accept any operations anymore and its file descriptor will be closed once
@@ -390,7 +384,9 @@ pub trait UdevHandler<B: Borrow<DrmBackend> + 'static, H: DrmHandler<B> + 'stati
     ///
     /// ## Panics
     /// Panics if you try to borrow the token of the belonging `UdevBackend` using this `StateProxy`.
-    fn device_removed<'a, S: Into<StateProxy<'a>>>(&mut self, state: S, device: &StateToken<DrmDevice<B>>);
+    fn device_removed<'a, S: Into<StateProxy<'a>>>(
+        &mut self, state: S, device: &StateToken<DrmDevice<SessionFdDrmDevice>>
+    );
     /// Called when the udev context has encountered and error.
     ///
     /// ## Panics

src/backend/winit.rs

@@ -1,44 +1,25 @@
 //! Implementation of backend traits for types provided by `winit`
 
 use backend::graphics::GraphicsBackend;
-use backend::graphics::egl::{self, EGLContext, EGLGraphicsBackend, GlAttributes, PixelFormat,
-                             PixelFormatRequirements, SwapBuffersError};
+use backend::graphics::egl::{EGLContext, EGLGraphicsBackend, EGLSurface, PixelFormat, SwapBuffersError};
+use backend::graphics::egl::context::GlAttributes;
+use backend::graphics::egl::error as egl_error;
+use backend::graphics::egl::error::Result as EGLResult;
+use backend::graphics::egl::native;
+use backend::graphics::egl::wayland::{EGLDisplay, EGLWaylandExtensions};
 use backend::input::{Axis, AxisSource, Event as BackendEvent, InputBackend, InputHandler, KeyState,
                      KeyboardKeyEvent, MouseButton, MouseButtonState, PointerAxisEvent, PointerButtonEvent,
                      PointerMotionAbsoluteEvent, Seat, SeatCapabilities, TouchCancelEvent, TouchDownEvent,
                      TouchMotionEvent, TouchSlot, TouchUpEvent, UnusedEvent};
 use nix::libc::c_void;
-use rental::TryNewError;
-use std::cell::Cell;
 use std::cmp;
 use std::error;
 use std::fmt;
 use std::rc::Rc;
+use wayland_client::egl as wegl;
+use wayland_server::Display;
 use winit::{ElementState, Event, EventsLoop, KeyboardInput, MouseButton as WinitMouseButton, MouseCursor,
-            MouseScrollDelta, Touch, TouchPhase, WindowBuilder, WindowEvent};
-use winit::os::unix::WindowExt;
-
-rental! {
-    mod rental {
-        use std::boxed::Box;
-        use ::winit::{Window as WinitWindow};
-        use ::backend::graphics::egl::{EGLContext, EGLSurface};
-
-        #[rental]
-        pub struct Window {
-            window: Box<WinitWindow>,
-            egl: EGL<'window>,
-        }
-
-        #[rental]
-        pub struct EGL<'a> {
-            context: Box<EGLContext<'a, WinitWindow>>,
-            surface: EGLSurface<'context, 'a, WinitWindow>,
-        }
-    }
-}
-
-use self::rental::{Window, EGL};
+            MouseScrollDelta, Touch, TouchPhase, Window as WinitWindow, WindowBuilder, WindowEvent};
 
 error_chain! {
     errors {
@@ -46,23 +27,42 @@ error_chain! {
         InitFailed {
             description("Failed to initialize a window")
         }
+
+        #[doc = "Context creation is not supported on the current window system"]
+        NotSupported {
+            description("Context creation is not supported on the current window system.")
+        }
     }
 
     links {
-        EGL(egl::Error, egl::ErrorKind) #[doc = "EGL error"];
+        EGL(egl_error::Error, egl_error::ErrorKind) #[doc = "EGL error"];
     }
 }
 
-impl<H> From<TryNewError<Error, H>> for Error {
-    fn from(err: TryNewError<Error, H>) -> Error {
-        err.0
+enum Window {
+    Wayland {
+        context: EGLContext<native::Wayland, WinitWindow>,
+        surface: EGLSurface<wegl::WlEglSurface>,
+    },
+    X11 {
+        context: EGLContext<native::X11, WinitWindow>,
+        surface: EGLSurface<native::XlibWindow>,
+    },
+}
+
+impl Window {
+    fn window(&self) -> &WinitWindow {
+        match self {
+            &Window::Wayland { ref context, .. } => &**context,
+            &Window::X11 { ref context, .. } => &**context,
         }
     }
+}
+
 /// Window with an active EGL Context created by `winit`. Implements the
 /// `EGLGraphicsBackend` graphics backend trait
 pub struct WinitGraphicsBackend {
     window: Rc<Window>,
-    ready: Cell<bool>,
     logger: ::slog::Logger,
 }
 
@@ -136,31 +136,26 @@ where
         .chain_err(|| ErrorKind::InitFailed)?;
     debug!(log, "Window created");
 
-    let window = Rc::new(Window::try_new(Box::new(winit_window), |window| {
-        EGL::try_new(
-            Box::new(match EGLContext::new_from_winit(
-                &*window,
-                attributes,
-                PixelFormatRequirements {
-                    hardware_accelerated: Some(true),
-                    color_bits: Some(24),
-                    alpha_bits: Some(8),
-                    ..Default::default()
+    let reqs = Default::default();
+    let window = Rc::new(
+        if native::NativeDisplay::<native::Wayland>::is_backend(&winit_window) {
+            let context =
+                EGLContext::<native::Wayland, WinitWindow>::new(winit_window, attributes, reqs, log.clone())?;
+            let surface = context.create_surface(())?;
+            Window::Wayland { context, surface }
+        } else if native::NativeDisplay::<native::X11>::is_backend(&winit_window) {
+            let context =
+                EGLContext::<native::X11, WinitWindow>::new(winit_window, attributes, reqs, log.clone())?;
+            let surface = context.create_surface(())?;
+            Window::X11 { context, surface }
+        } else {
+            bail!(ErrorKind::NotSupported);
         },
-                log.clone(),
-            ) {
-                Ok(context) => context,
-                Err(err) => bail!(err),
-            }),
-            |context| context.create_surface(window),
-        ).map_err(egl::Error::from)
-            .map_err(Error::from)
-    })?);
+    );
 
     Ok((
         WinitGraphicsBackend {
             window: window.clone(),
-            ready: Cell::new(false),
             logger: log.new(o!("smithay_winit_component" => "graphics")),
         },
         WinitInputBackend {
@@ -189,7 +184,7 @@ impl GraphicsBackend for WinitGraphicsBackend {
 
     fn set_cursor_position(&self, x: u32, y: u32) -> ::std::result::Result<(), ()> {
         debug!(self.logger, "Setting cursor position to {:?}", (x, y));
-        self.window.head().set_cursor_position(x as i32, y as i32)
+        self.window.window().set_cursor_position(x as i32, y as i32)
     }
 
     fn set_cursor_representation(
@@ -197,7 +192,7 @@ impl GraphicsBackend for WinitGraphicsBackend {
     ) -> ::std::result::Result<(), ()> {
         // Cannot log this one, as `CursorFormat` is not `Debug` and should not be
         debug!(self.logger, "Changing cursor representation");
-        self.window.head().set_cursor(*cursor);
+        self.window.window().set_cursor(*cursor);
         Ok(())
     }
 }
@@ -205,44 +200,62 @@ impl GraphicsBackend for WinitGraphicsBackend {
 impl EGLGraphicsBackend for WinitGraphicsBackend {
     fn swap_buffers(&self) -> ::std::result::Result<(), SwapBuffersError> {
         trace!(self.logger, "Swapping buffers");
-        if !self.ready.get() {
-            if self.window.head().is_ready() {
-                // avoid locking the mutex every time once the window is ready
-                self.ready.set(true);
-            } else {
-                // Not yet ready, just silently ignore the swap-buffers call
-                return Ok(());
+        match *self.window {
+            Window::Wayland { ref surface, .. } => surface.swap_buffers(),
+            Window::X11 { ref surface, .. } => surface.swap_buffers(),
         }
     }
-        self.window
-            .rent(|egl| egl.rent(|surface| surface.swap_buffers()))
-    }
 
     unsafe fn get_proc_address(&self, symbol: &str) -> *const c_void {
         trace!(self.logger, "Getting symbol for {:?}", symbol);
-        self.window.rent(|egl| egl.head().get_proc_address(symbol))
+        match *self.window {
+            Window::Wayland { ref context, .. } => context.get_proc_address(symbol),
+            Window::X11 { ref context, .. } => context.get_proc_address(symbol),
+        }
     }
 
     fn get_framebuffer_dimensions(&self) -> (u32, u32) {
         self.window
-            .head()
-            .get_inner_size_pixels()
+            .window()
+            .get_inner_size()
             .expect("Window does not exist anymore")
     }
 
     fn is_current(&self) -> bool {
-        self.window
-            .rent(|egl| egl.rent_all(|egl| egl.context.is_current() && egl.surface.is_current()))
+        match *self.window {
+            Window::Wayland {
+                ref context,
+                ref surface,
+            } => context.is_current() && surface.is_current(),
+            Window::X11 {
+                ref context,
+                ref surface,
+            } => context.is_current() && surface.is_current(),
+        }
     }
 
     unsafe fn make_current(&self) -> ::std::result::Result<(), SwapBuffersError> {
-        debug!(self.logger, "Setting EGL context to be the current context");
-        self.window
-            .rent(|egl| egl.rent(|surface| surface.make_current()))
+        trace!(self.logger, "Setting EGL context to be the current context");
+        match *self.window {
+            Window::Wayland { ref surface, .. } => surface.make_current(),
+            Window::X11 { ref surface, .. } => surface.make_current(),
+        }
     }
 
     fn get_pixel_format(&self) -> PixelFormat {
-        self.window.rent(|egl| egl.head().get_pixel_format())
+        match *self.window {
+            Window::Wayland { ref context, .. } => context.get_pixel_format(),
+            Window::X11 { ref context, .. } => context.get_pixel_format(),
+        }
+    }
+}
+
+impl EGLWaylandExtensions for WinitGraphicsBackend {
+    fn bind_wl_display(&self, display: &Display) -> EGLResult<EGLDisplay> {
+        match *self.window {
+            Window::Wayland { ref context, .. } => context.bind_wl_display(display),
+            Window::X11 { ref context, .. } => context.bind_wl_display(display),
+        }
     }
 }
 
@@ -326,8 +339,8 @@ impl PointerMotionAbsoluteEvent for WinitMouseMovedEvent {
         cmp::min(
             (self.x * width as f64
                 / self.window
-                    .head()
-                    .get_inner_size_points()
+                    .window()
+                    .get_inner_size()
                     .unwrap_or((width, 0))
                     .0 as f64) as u32,
             0,
@@ -338,8 +351,8 @@ impl PointerMotionAbsoluteEvent for WinitMouseMovedEvent {
         cmp::min(
             (self.y * height as f64
                 / self.window
-                    .head()
-                    .get_inner_size_points()
+                    .window()
+                    .get_inner_size()
                     .unwrap_or((0, height))
                     .1 as f64) as u32,
             0,
@@ -439,8 +452,8 @@ impl TouchDownEvent for WinitTouchStartedEvent {
         cmp::min(
             self.location.0 as i32 * width as i32
                 / self.window
-                    .head()
-                    .get_inner_size_points()
+                    .window()
+                    .get_inner_size()
                     .unwrap_or((width, 0))
                     .0 as i32,
             0,
@@ -451,8 +464,8 @@ impl TouchDownEvent for WinitTouchStartedEvent {
         cmp::min(
             self.location.1 as i32 * height as i32
                 / self.window
-                    .head()
-                    .get_inner_size_points()
+                    .window()
+                    .get_inner_size()
                     .unwrap_or((0, height))
                     .1 as i32,
             0,
@@ -491,8 +504,8 @@ impl TouchMotionEvent for WinitTouchMovedEvent {
     fn x_transformed(&self, width: u32) -> u32 {
         self.location.0 as u32 * width
             / self.window
-                .head()
-                .get_inner_size_points()
+                .window()
+                .get_inner_size()
                 .unwrap_or((width, 0))
                 .0
     }
@@ -500,8 +513,8 @@ impl TouchMotionEvent for WinitTouchMovedEvent {
     fn y_transformed(&self, height: u32) -> u32 {
         self.location.1 as u32 * height
             / self.window
-                .head()
-                .get_inner_size_points()
+                .window()
+                .get_inner_size()
                 .unwrap_or((0, height))
                 .1
     }
@@ -626,14 +639,13 @@ impl InputBackend for WinitInputBackend {
                     match (event, handler.as_mut()) {
                         (WindowEvent::Resized(x, y), _) => {
                             trace!(logger, "Resizing window to {:?}", (x, y));
-                            window.head().set_inner_size(x, y);
-                            window.rent(|egl| {
-                                egl.rent(|surface| {
-                                    if let Some(wegl_surface) = (**surface).as_ref() {
-                                        wegl_surface.resize(x as i32, y as i32, 0, 0)
+                            window.window().set_inner_size(x, y);
+                            match **window {
+                                Window::Wayland { ref surface, .. } => {
+                                    surface.resize(x as i32, y as i32, 0, 0)
                                 }
-                                })
-                            });
+                                _ => {}
+                            };
                         }
                         (
                             WindowEvent::KeyboardInput {
@@ -667,7 +679,7 @@ impl InputBackend for WinitInputBackend {
                             )
                         }
                         (
-                            WindowEvent::MouseMoved {
+                            WindowEvent::CursorMoved {
                                 position: (x, y), ..
                             },
                             Some(handler),

src/lib.rs

@@ -8,13 +8,12 @@
 #![recursion_limit = "1024"]
 
 extern crate image;
-#[macro_use]
+#[cfg_attr(feature = "backend_session", macro_use)]
 extern crate nix;
-#[macro_use]
-extern crate rental;
 extern crate tempfile;
 extern crate wayland_protocols;
 extern crate wayland_server;
+extern crate wayland_sys;
 extern crate xkbcommon;
 
 #[cfg(feature = "backend_drm")]
@@ -48,6 +47,9 @@ extern crate slog_stdlog;
 #[macro_use]
 extern crate error_chain;
 
+#[macro_use]
+extern crate lazy_static;
+
 pub mod backend;
 pub mod wayland;
 pub mod utils;

src/wayland/compositor/mod.rs

@@ -72,9 +72,7 @@
 //!
 //! As you can see in the previous example, in the end we are retrieving a token from
 //! the init function. This token is necessary to retrieve the metadata associated with
-//! a surface. It can be cloned, and is sendable accross threads (as long as your
-//! `Mydata` and `MyRoles` are `Send` too). See `CompositorToken` for
-//! the details of what it enables you.
+//! a surface. It can be cloned. See `CompositorToken` for the details of what it enables you.
 //!
 //! The surface metadata is held in the `SurfaceAttributes` struct. In contains double-buffered
 //! state pending from the client as defined by the protocol for `wl_surface`, as well as your
@@ -248,9 +246,6 @@ pub struct CompositorToken<U, R, ID> {
     _idata: ::std::marker::PhantomData<*mut ID>,
 }
 
-unsafe impl<U: Send, R: Send, ID> Send for CompositorToken<U, R, ID> {}
-unsafe impl<U: Send, R: Send, ID> Sync for CompositorToken<U, R, ID> {}
-
 // we implement them manually because #[derive(..)] would require
 // U: Clone and R: Clone
 impl<U, R, ID> Copy for CompositorToken<U, R, ID> {}
@@ -270,7 +265,7 @@ impl<U, R, ID> CompositorToken<U, R, ID> {
     }
 }
 
-impl<U: Send + 'static, R: Send + 'static, ID: 'static> CompositorToken<U, R, ID> {
+impl<U: 'static, R: 'static, ID: 'static> CompositorToken<U, R, ID> {
     /// Access the data of a surface
     ///
     /// The closure will be called with the contents of the data associated with this surface.

src/wayland/seat/mod.rs

@@ -236,7 +236,9 @@ fn seat_global_bind(
 ) {
     evlh.register(&seat, seat_implementation(), token.clone(), None);
     let seat_mgr = evlh.state().get_mut(token);
+    if seat.version() >= 2 {
         seat.name(seat_mgr.name.clone());
+    }
     seat.capabilities(seat_mgr.compute_caps());
     seat_mgr.known_seats.push(seat);
 }

src/wayland/shell/mod.rs

@@ -449,8 +449,7 @@ impl<SD> ShellClient<SD> {
         }
         match self.kind {
             ShellClientKind::Wl(ref shell) => {
-                let mutex =
-                    unsafe { &*(shell.get_user_data() as *mut self::wl_handlers::ShellUserData<SD>) };
+                let mutex = unsafe { &*(shell.get_user_data() as *mut self::wl_handlers::ShellUserData<SD>) };
                 let mut guard = mutex.lock().unwrap();
                 if guard.0.pending_ping == 0 {
                     return Err(());
@@ -487,8 +486,7 @@ impl<SD> ShellClient<SD> {
         }
         match self.kind {
             ShellClientKind::Wl(ref shell) => {
-                let mutex =
-                    unsafe { &*(shell.get_user_data() as *mut self::wl_handlers::ShellUserData<SD>) };
+                let mutex = unsafe { &*(shell.get_user_data() as *mut self::wl_handlers::ShellUserData<SD>) };
                 let mut guard = mutex.lock().unwrap();
                 Ok(f(&mut guard.0.data))
             }

src/wayland/shell/wl_handlers.rs

@@ -271,8 +271,7 @@ where
 {
     wl_shell_surface::Implementation {
         pong: |evlh, idata, _, shell_surface, serial| {
-            let &(_, ref shell) =
-                unsafe { &*(shell_surface.get_user_data() as *mut ShellSurfaceUserData) };
+            let &(_, ref shell) = unsafe { &*(shell_surface.get_user_data() as *mut ShellSurfaceUserData) };
             let valid = {
                 let mutex = unsafe { &*(shell.get_user_data() as *mut ShellUserData<SD>) };
                 let mut guard = mutex.lock().unwrap();

src/wayland/shell/xdg_handlers.rs

@@ -230,9 +230,8 @@ fn destroy_surface(surface: &zxdg_surface_v6::ZxdgSurfaceV6) {
     let ptr = surface.get_user_data();
     surface.set_user_data(::std::ptr::null_mut());
     // drop the state
-    let data = unsafe {
-        Box::from_raw(ptr as *mut (zxdg_surface_v6::ZxdgSurfaceV6, zxdg_shell_v6::ZxdgShellV6))
-    };
+    let data =
+        unsafe { Box::from_raw(ptr as *mut (zxdg_surface_v6::ZxdgSurfaceV6, zxdg_shell_v6::ZxdgShellV6)) };
     // explicit call to drop to not forget what we're doing here
     ::std::mem::drop(data);
 }
@@ -544,9 +543,8 @@ where
             with_surface_toplevel_data(idata, toplevel, |toplevel_data| {
                 toplevel_data.parent = parent.map(|toplevel_surface_parent| {
                     let parent_ptr = toplevel_surface_parent.get_user_data();
-                    let &(ref parent_surface, _) = unsafe {
-                        &*(parent_ptr as *mut (wl_surface::WlSurface, zxdg_shell_v6::ZxdgShellV6))
-                    };
+                    let &(ref parent_surface, _) =
+                        unsafe { &*(parent_ptr as *mut (wl_surface::WlSurface, zxdg_shell_v6::ZxdgShellV6)) };
                     unsafe { parent_surface.clone_unchecked() }
                 })
             });

vagga.yaml

@@ -43,6 +43,9 @@ containers:
             - !Container base
             - !Env HOME: /work/.vagga/nightly-home
             - !Sh curl https://sh.rustup.rs -sSf | sh -s -- -y --default-host x86_64-unknown-linux-gnu --default-toolchain nightly --no-modify-path
+            - !Env PATH: /bin:/sbin:/usr/bin:/usr/sbin:/usr/local/bin:/usr/local/sbin:/work/.vagga/nightly-home/.cargo/bin:/work/.vagga/nightly-home/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/bin/
+            - !Sh rustup self update
+            - !Sh rustup component add rustfmt-preview
 
 commands:
     update-stable: !Command
@@ -58,8 +61,7 @@ commands:
     update-nightly: !Command
         description: Update container
         container: nightly
-        run: |
-            rustup update
+        run: rustup update
 
     cargo-stable: !Command
         description: Run cargo