From df2722437259b708912017ac16c8e092d64b51fa Mon Sep 17 00:00:00 2001
From: Victor Brekenfeld <github@drakulix.de>
Date: Sun, 19 Apr 2020 01:26:45 +0200
Subject: [PATCH] gbm: implement CursorBackend generically

---
 src/backend/drm/gbm/surface.rs | 41 +++++++++-------------------------
 src/backend/winit.rs           | 15 +++++--------
 2 files changed, 17 insertions(+), 39 deletions(-)

diff --git a/src/backend/drm/gbm/surface.rs b/src/backend/drm/gbm/surface.rs
index dd2709f..ef682d5 100644
--- a/src/backend/drm/gbm/surface.rs
+++ b/src/backend/drm/gbm/surface.rs
@@ -6,11 +6,8 @@ use gbm::{self, BufferObject, BufferObjectFlags, Format as GbmFormat, SurfaceBuf
 use image::{ImageBuffer, Rgba};
 
 use std::cell::{Cell, RefCell};
-use std::os::unix::io::AsRawFd;
 use std::rc::Rc;
 
-#[cfg(feature = "backend_drm_legacy")]
-use crate::backend::drm::legacy::LegacyDrmDevice;
 use crate::backend::graphics::CursorBackend;
 use crate::backend::graphics::SwapBuffersError;
 
@@ -172,32 +169,12 @@ impl<D: RawDevice + 'static> Surface for GbmSurfaceInternal<D> {
     }
 }
 
-// FIXME:
-//
-// Option 1: When there is GAT support, impl `GraphicsBackend` for `LegacyDrmBackend`
-//           using a new generic `B: Buffer` and use this:
-/*
-impl<'a, D: RawDevice + 'static> CursorBackend<'a> for GbmSurfaceInternal<D>
+#[cfg(feature = "backend_drm")]
+impl<D: RawDevice + 'static> CursorBackend for GbmSurfaceInternal<D>
 where
-    <D as RawDevice>::Surface: CursorBackend<'a>,
-    <<D as RawDevice>::Surface as CursorBackend<'a>>::CursorFormat: Buffer,
-    <<D as RawDevice>::Surface as CursorBackend<'a>>::Error: ::std::error::Error + Send
+    <D as RawDevice>::Surface: CursorBackend<CursorFormat = dyn drm::buffer::Buffer>,
+    <<D as RawDevice>::Surface as CursorBackend>::Error: ::std::error::Error + Send,
 {
-*/
-//
-// Option 2: When equality checks in where clauses are supported, we could at least do this:
-/*
-impl<'a, D: RawDevice + 'static> GraphicsBackend<'a> for GbmSurfaceInternal<D>
-where
-    <D as RawDevice>::Surface: CursorBackend<'a>,
-    <<D as RawDevice>::Surface as CursorBackend<'a>>::CursorFormat=&'a Buffer,
-    <<D as RawDevice>::Surface as CursorBackend<'a>>::Error: ::std::error::Error + Send
-{
-*/
-// But for now got to do this:
-
-#[cfg(feature = "backend_drm_legacy")]
-impl<A: AsRawFd + 'static> CursorBackend for GbmSurfaceInternal<LegacyDrmDevice<A>> {
     type CursorFormat = ImageBuffer<Rgba<u8>, Vec<u8>>;
     type Error = Error<<<D as Device>::Surface as CursorBackend>::Error>;
 
@@ -346,10 +323,14 @@ impl<D: RawDevice + 'static> Surface for GbmSurface<D> {
     }
 }
 
-#[cfg(feature = "backend_drm_legacy")]
-impl<A: AsRawFd + 'static> CursorBackend for GbmSurface<LegacyDrmDevice<A>> {
+#[cfg(feature = "backend_drm")]
+impl<D: RawDevice + 'static> CursorBackend for GbmSurface<D>
+where
+    <D as RawDevice>::Surface: CursorBackend<CursorFormat = dyn drm::buffer::Buffer>,
+    <<D as RawDevice>::Surface as CursorBackend>::Error: ::std::error::Error + Send,
+{
     type CursorFormat = ImageBuffer<Rgba<u8>, Vec<u8>>;
-    type Error = <Self as Surface>::Error;
+    type Error = Error<<<D as Device>::Surface as CursorBackend>::Error>;
 
     fn set_cursor_position(&self, x: u32, y: u32) -> Result<(), Self::Error> {
         self.0.set_cursor_position(x, y)
diff --git a/src/backend/winit.rs b/src/backend/winit.rs
index 4c4e6ea..c1960bb 100644
--- a/src/backend/winit.rs
+++ b/src/backend/winit.rs
@@ -247,8 +247,8 @@ impl WinitGraphicsBackend {
     }
 }
 
-impl<'a> CursorBackend<'a> for WinitGraphicsBackend {
-    type CursorFormat = &'a CursorIcon;
+impl CursorBackend for WinitGraphicsBackend {
+    type CursorFormat = CursorIcon;
     type Error = ();
 
     fn set_cursor_position(&self, x: u32, y: u32) -> ::std::result::Result<(), ()> {
@@ -261,14 +261,11 @@ impl<'a> CursorBackend<'a> for WinitGraphicsBackend {
             })
     }
 
-    fn set_cursor_representation<'b>(
-        &'b self,
-        cursor: Self::CursorFormat,
+    fn set_cursor_representation(
+        &self,
+        cursor: &Self::CursorFormat,
         _hotspot: (u32, u32),
-    ) -> ::std::result::Result<(), ()>
-    where
-        'a: 'b,
-    {
+    ) -> ::std::result::Result<(), ()> {
         // Cannot log this one, as `CursorFormat` is not `Debug` and should not be
         debug!(self.logger, "Changing cursor representation");
         self.window.window().set_cursor_icon(*cursor);