feat: add OpenHarmony platform support

.github/CODEOWNERS

@@ -21,3 +21,7 @@
 
 # X11
 /src/x11.rs         @notgull
+
+
+# OpenHarmony
+/src/ohos.rs        @richerfu

Cargo.toml

@@ -48,7 +48,10 @@ tracing = { version = "0.1.41", default-features = false }
 bytemuck = "1.12.3"
 ndk = "0.9.0"
 
-[target.'cfg(all(unix, not(any(target_vendor = "apple", target_os = "android", target_os = "redox"))))'.dependencies]
+[target.'cfg(target_env = "ohos")'.dependencies]
+ohos-native-window-binding = { version = "0.1" }
+
+[target.'cfg(all(unix, not(any(target_vendor = "apple", target_os = "android", target_os = "redox", target_env = "ohos"))))'.dependencies]
 as-raw-xcb-connection = { version = "1.0.0", optional = true }
 bytemuck = { version = "1.12.3", optional = true }
 drm = { version = "0.14.1", default-features = false, optional = true }
@@ -145,6 +148,11 @@ winit = "0.30.0"
 winit = { version = "0.30.0", features = ["android-native-activity"] }
 android-activity = "0.6"
 
+[target.'cfg(target_env = "ohos")'.dev-dependencies]
+winit = { version = "0.30" }
+openharmony-ability = { version = "0.0.4" }
+openharmony-ability-derive = { version = "0.0.3" }
+
 [dev-dependencies.image]
 version = "0.25.0"
 # Disable rayon on web
@@ -169,6 +177,11 @@ members = ["run-wasm"]
 name = "winit_android"
 crate-type = ["cdylib"]
 
+[[example]]
+# Run with `ohrs build -- --example winit_android`
+name = "winit_ohos"
+crate-type = ["cdylib"]
+
 [[example]]
 # Run with `cargo apk r --example winit_multithread_android`
 name = "winit_multithread_android"

benches/buffer_mut.rs

@@ -9,7 +9,7 @@ fn buffer_mut(c: &mut Criterion) {
         let _ = c;
     }
 
-    #[cfg(not(any(target_arch = "wasm32", target_arch = "wasm64")))]
+    #[cfg(not(any(target_arch = "wasm32", target_arch = "wasm64", target_env = "ohos")))]
     {
         use criterion::black_box;
         use softbuffer::{Context, Surface};

build.rs

@@ -5,7 +5,7 @@ fn main() {
     println!("cargo:rustc-check-cfg=cfg(wayland_platform)");
 
     cfg_aliases::cfg_aliases! {
-        free_unix: { all(unix, not(any(target_vendor = "apple", target_os = "android", target_os = "redox"))) },
+        free_unix: { all(unix, not(any(target_vendor = "apple", target_os = "android", target_os = "redox", target_env = "ohos"))) },
         kms_platform: { all(feature = "kms", free_unix, not(target_arch = "wasm32")) },
         x11_platform: { all(feature = "x11", free_unix, not(target_arch = "wasm32")) },
         wayland_platform: { all(feature = "wayland", free_unix, not(target_arch = "wasm32")) },

examples/utils/winit_app.rs

@@ -10,11 +10,14 @@ use winit::window::{Window, WindowAttributes, WindowId};
 /// Run a Winit application.
 #[allow(unused_mut)]
 pub(crate) fn run_app(event_loop: EventLoop<()>, mut app: impl ApplicationHandler<()> + 'static) {
-    #[cfg(not(any(target_arch = "wasm32", target_arch = "wasm64")))]
+    #[cfg(not(any(target_arch = "wasm32", target_arch = "wasm64", target_env = "ohos")))]
     event_loop.run_app(&mut app).unwrap();
 
     #[cfg(any(target_arch = "wasm32", target_arch = "wasm64"))]
     winit::platform::web::EventLoopExtWebSys::spawn_app(event_loop, app);
+
+    #[cfg(target_env = "ohos")]
+    winit::platform::ohos::EventLoopExtOpenHarmony::spawn_app(event_loop, app);
 }
 
 /// Create a window from a set of window attributes.

examples/winit.rs

@@ -6,11 +6,14 @@ use winit::keyboard::{Key, NamedKey};
 #[path = "utils/winit_app.rs"]
 mod winit_app;
 
-#[cfg(not(target_os = "android"))]
+#[cfg(not(any(target_os = "android", target_env = "ohos")))]
 fn main() {
     entry(EventLoop::new().unwrap())
 }
 
+#[cfg(any(target_os = "android", target_env = "ohos"))]
+fn main() {}
+
 pub(crate) fn entry(event_loop: EventLoop<()>) {
     let app = winit_app::WinitAppBuilder::with_init(
         |elwt| {

examples/winit_ohos.rs

@@ -0,0 +1,18 @@
+#![cfg(target_env = "ohos")]
+
+pub use winit::platform::ohos::{ability::OpenHarmonyApp, EventLoopBuilderExtOpenHarmony};
+use winit::{event_loop::EventLoop, platform::ohos::ability::ability};
+
+#[path = "winit.rs"]
+mod desktop_example;
+
+/// Run with `ohrs build -- --example winit_ohos`
+#[ability]
+fn openharmony(app: OpenHarmonyApp) {
+    let mut builder = EventLoop::builder();
+
+    // Install the Android event loop extension if necessary.
+    builder.with_openharmony_app(app);
+
+    desktop_example::entry(builder.build().unwrap())
+}

src/backend_dispatch.rs

@@ -194,4 +194,6 @@ make_dispatch! {
     Web(backends::web::WebDisplayImpl<D>, backends::web::WebImpl<D, W>, backends::web::BufferImpl<'a, D, W>),
     #[cfg(target_os = "redox")]
     Orbital(D, backends::orbital::OrbitalImpl<D, W>, backends::orbital::BufferImpl<'a, D, W>),
+    #[cfg(target_env = "ohos")]
+    Ohos(D,backends::ohos::OpenHarmonyImpl<D, W>, backends::ohos::BufferImpl<'a, D, W>),
 }

src/backends/mod.rs

@@ -7,6 +7,8 @@ pub(crate) mod android;
 pub(crate) mod cg;
 #[cfg(kms_platform)]
 pub(crate) mod kms;
+#[cfg(target_env = "ohos")]
+pub(crate) mod ohos;
 #[cfg(target_os = "redox")]
 pub(crate) mod orbital;
 #[cfg(wayland_platform)]

src/backends/ohos.rs

@@ -0,0 +1,166 @@
+//! Implementation of software buffering for OpenHarmony.
+
+use std::marker::PhantomData;
+use std::num::{NonZeroI32, NonZeroU32};
+
+#[cfg(doc)]
+use raw_window_handle::OhosNdkWindowHandle;
+use raw_window_handle::{HasDisplayHandle, HasWindowHandle, RawWindowHandle};
+
+use crate::error::InitError;
+use crate::{BufferInterface, Rect, SoftBufferError, SurfaceInterface};
+use ohos_native_window_binding::{NativeBufferFormat, NativeWindow, NativeWindowBuffer};
+
+/// The handle to a window for software buffering.
+pub struct OpenHarmonyImpl<D, W> {
+    native_window: NativeWindow,
+    window: W,
+    _display: PhantomData<D>,
+}
+
+impl<D: HasDisplayHandle, W: HasWindowHandle> SurfaceInterface<D, W> for OpenHarmonyImpl<D, W> {
+    type Context = D;
+    type Buffer<'a>
+        = BufferImpl<'a, D, W>
+    where
+        Self: 'a;
+
+    /// Create a new [`OpenHarmonyImpl`] from an [`OhosNdkWindowHandle`].
+    fn new(window: W, _display: &Self::Context) -> Result<Self, InitError<W>> {
+        let raw = window.window_handle()?.as_raw();
+        let RawWindowHandle::OhosNdk(a) = raw else {
+            return Err(InitError::Unsupported(window));
+        };
+
+        // Acquire a new owned reference to the window, that will be freed on drop.
+        // SAFETY: We have confirmed that the window handle is valid.
+        let native_window = NativeWindow::clone_from_ptr(a.native_window.as_ptr());
+
+        Ok(Self {
+            native_window,
+            _display: PhantomData,
+            window,
+        })
+    }
+
+    #[inline]
+    fn window(&self) -> &W {
+        &self.window
+    }
+
+    /// Also changes the pixel format to [`HardwareBufferFormat::R8G8B8A8_UNORM`].
+    fn resize(&mut self, width: NonZeroU32, height: NonZeroU32) -> Result<(), SoftBufferError> {
+        let (width, height) = (|| {
+            let width = NonZeroI32::try_from(width).ok()?;
+            let height = NonZeroI32::try_from(height).ok()?;
+            Some((width, height))
+        })()
+        .ok_or(SoftBufferError::SizeOutOfRange { width, height })?;
+
+        self.native_window
+            .set_buffer_geometry(width.into(), height.into())
+            .map_err(|err| {
+                SoftBufferError::PlatformError(
+                    Some("Failed to set buffer geometry on NativeWindow".to_owned()),
+                    Some(Box::new(err)),
+                )
+            })
+    }
+
+    fn buffer_mut(&mut self) -> Result<BufferImpl<'_, D, W>, SoftBufferError> {
+        let native_window_buffer = self.native_window.request_buffer(None).map_err(|err| {
+            SoftBufferError::PlatformError(
+                Some("Failed to request native window buffer".to_owned()),
+                Some(Box::new(err)),
+            )
+        })?;
+
+        if !matches!(
+            native_window_buffer.format(),
+            // These are the only formats we support
+            NativeBufferFormat::RGBA_8888 | NativeBufferFormat::RGBX_8888
+        ) {
+            return Err(SoftBufferError::PlatformError(
+                Some(format!(
+                    "Unexpected buffer format {:?}, please call \
+                    .resize() first to change it to RGBx8888",
+                    native_window_buffer.format()
+                )),
+                None,
+            ));
+        }
+        let size = (native_window_buffer.width() * native_window_buffer.height())
+            .try_into()
+            .map_err(|e| {
+                SoftBufferError::PlatformError(
+                    Some("Failed to convert width to u32".to_owned()),
+                    Some(Box::new(e)),
+                )
+            })?;
+        let buffer = vec![0; size];
+
+        Ok(BufferImpl {
+            native_window_buffer,
+            buffer,
+            marker: PhantomData,
+        })
+    }
+
+    /// Fetch the buffer from the window.
+    fn fetch(&mut self) -> Result<Vec<u32>, SoftBufferError> {
+        Err(SoftBufferError::Unimplemented)
+    }
+}
+
+pub struct BufferImpl<'a, D: ?Sized, W> {
+    native_window_buffer: NativeWindowBuffer<'a>,
+    buffer: Vec<u32>,
+    marker: PhantomData<(&'a D, &'a W)>,
+}
+
+unsafe impl<'a, D, W> Send for BufferImpl<'a, D, W> {}
+
+impl<'a, D: HasDisplayHandle, W: HasWindowHandle> BufferInterface for BufferImpl<'a, D, W> {
+    #[inline]
+    fn pixels(&self) -> &[u32] {
+        &self.buffer
+    }
+
+    #[inline]
+    fn pixels_mut(&mut self) -> &mut [u32] {
+        &mut self.buffer
+    }
+
+    #[inline]
+    fn age(&self) -> u8 {
+        0
+    }
+
+    // TODO: This function is pretty slow this way
+    fn present(mut self) -> Result<(), SoftBufferError> {
+        let input_lines = self.buffer.chunks(self.native_window_buffer.width() as _);
+        for (output, input) in self
+            .native_window_buffer
+            .lines()
+            // Unreachable as we checked before that this is a valid, mappable format
+            .unwrap()
+            .zip(input_lines)
+        {
+            // .lines() removed the stride
+            assert_eq!(output.len(), input.len() * 4);
+
+            for (i, pixel) in input.iter().enumerate() {
+                // Swizzle colors from RGBX to BGR
+                let [b, g, r, _] = pixel.to_le_bytes();
+                output[i * 4].write(b);
+                output[i * 4 + 1].write(g);
+                output[i * 4 + 2].write(r);
+            }
+        }
+        Ok(())
+    }
+
+    fn present_with_damage(self, _damage: &[Rect]) -> Result<(), SoftBufferError> {
+        self.present()
+    }
+}

src/lib.rs

@@ -303,6 +303,7 @@ fn window_handle_type_name(handle: &RawWindowHandle) -> &'static str {
         RawWindowHandle::Drm(_) => "DRM",
         RawWindowHandle::Gbm(_) => "GBM",
         RawWindowHandle::Haiku(_) => "Haiku",
+        RawWindowHandle::OhosNdk(_) => "OhosNdk",
         _ => "Unknown Name", //don't completely fail to compile if there is a new raw window handle type that's added at some point
     }
 }
@@ -321,6 +322,7 @@ fn display_handle_type_name(handle: &RawDisplayHandle) -> &'static str {
         RawDisplayHandle::Haiku(_) => "Haiku",
         RawDisplayHandle::Windows(_) => "Windows",
         RawDisplayHandle::Android(_) => "Android",
+        RawDisplayHandle::Ohos(_) => "Ohos",
         _ => "Unknown Name", //don't completely fail to compile if there is a new raw window handle type that's added at some point
     }
 }