winit-orbital: Implement pump_app_events

Author: willnode

Cargo.toml

@@ -81,8 +81,8 @@ xkbcommon-dl = "0.4.2"
 
 # Orbital dependencies.
 libredox = "0.1.12"
-orbclient = { version = "0.3.47", default-features = false }
-redox_event = { package = "redox_event", version = "0.4.5" }
+orbclient = { version = "0.4.3", default-features = false }
+redox_event = { package = "redox_event", version = "0.4.8" }
 
 # Web dependencies.
 atomic-waker = "1"

winit-orbital/src/event_loop.rs

@@ -1,22 +1,22 @@
 use std::cell::Cell;
 use std::collections::VecDeque;
-use std::os::raw::c_long;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::{Arc, Mutex, mpsc};
-use std::time::Instant;
+use std::time::{Duration, Instant};
 use std::{iter, mem, slice};
 
 use bitflags::bitflags;
 use orbclient::{
     ButtonEvent, EventOption, FocusEvent, HoverEvent, KeyEvent, MouseEvent, MouseRelativeEvent,
     MoveEvent, QuitEvent, ResizeEvent, ScrollEvent, TextInputEvent,
 };
-use redox_event::{EventFlags, EventQueue};
+use redox_event::{EventFlags, EventQueue, UserData};
 use smol_str::SmolStr;
 use winit_core::application::ApplicationHandler;
 use winit_core::cursor::{CustomCursor, CustomCursorSource};
 use winit_core::error::{EventLoopError, NotSupportedError, RequestError};
 use winit_core::event::{self, Ime, Modifiers, StartCause};
+use winit_core::event_loop::pump_events::PumpStatus;
 use winit_core::event_loop::{
     ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents,
     EventLoopProxy as CoreEventLoopProxy, EventLoopProxyProvider,
@@ -31,6 +31,9 @@ use winit_core::window::{Theme, Window as CoreWindow, WindowId};
 use crate::window::Window;
 use crate::{RedoxSocket, TimeSocket, WindowProperties};
 
+/// timeout from redox_syscall
+const EVENT_TIMEOUT_ID: usize = usize::MAX - 2;
+
 fn convert_scancode(scancode: u8) -> (PhysicalKey, Option<NamedKey>) {
     // Key constants from https://docs.rs/orbclient/latest/orbclient/event/index.html
     let (key_code, named_key_opt) = match scancode {
@@ -157,6 +160,15 @@ fn convert_scancode(scancode: u8) -> (PhysicalKey, Option<NamedKey>) {
     (PhysicalKey::Code(key_code), named_key_opt)
 }
 
+pub fn scancode_to_physicalkey(scancode: u32) -> PhysicalKey {
+    convert_scancode(scancode.try_into().unwrap_or_default()).0
+}
+
+pub fn physicalkey_to_scancode(_physical_key: PhysicalKey) -> Option<u32> {
+    // TODO
+    None
+}
+
 fn element_state(pressed: bool) -> event::ElementState {
     if pressed { event::ElementState::Pressed } else { event::ElementState::Released }
 }
@@ -296,6 +308,8 @@ impl EventState {
 
 #[derive(Debug)]
 pub struct EventLoop {
+    /// Has `run` or `run_on_demand` been called or a call to `pump_events` that starts the loop
+    loop_running: bool,
     windows: Vec<(Arc<RedoxSocket>, EventState)>,
     window_target: ActiveEventLoop,
     user_events_receiver: mpsc::Receiver<()>,
@@ -323,6 +337,7 @@ impl EventLoop {
             .map_err(|error| os_error!(format!("{error}")))?;
 
         Ok(Self {
+            loop_running: false,
             windows: Vec::new(),
             window_target: ActiveEventLoop {
                 control_flow: Cell::new(ControlFlow::default()),
@@ -508,11 +523,28 @@ impl EventLoop {
         &mut self,
         mut app: A,
     ) -> Result<(), EventLoopError> {
-        let mut start_cause = StartCause::Init;
         loop {
-            app.new_events(&self.window_target, start_cause);
+            match self.pump_app_events(None, &mut app) {
+                PumpStatus::Exit(0) => {
+                    break Ok(());
+                },
+                PumpStatus::Exit(code) => {
+                    break Err(EventLoopError::ExitFailure(code));
+                },
+                _ => {
+                    continue;
+                },
+            }
+        }
+    }
+
+    fn single_iteration<A: ApplicationHandler>(&mut self, app: &mut A, cause: StartCause) {
+        // TODO: Unindent
+        {
+            app.new_events(&self.window_target, cause);
 
-            if start_cause == StartCause::Init {
+            if cause == StartCause::Init {
+                // NB: For consistency all platforms must call `can_create_surfaces`
                 app.can_create_surfaces(&self.window_target);
             }
 
@@ -572,7 +604,7 @@ impl EventLoop {
                         orbital_event.to_option(),
                         event_state,
                         &self.window_target,
-                        &mut app,
+                        app,
                     );
                 }
 
@@ -616,75 +648,82 @@ impl EventLoop {
             }
 
             app.about_to_wait(&self.window_target);
+        }
+    }
 
-            if self.window_target.exiting() {
-                break;
-            }
+    pub fn pump_app_events<A: ApplicationHandler>(
+        &mut self,
+        timeout: Option<Duration>,
+        mut app: A,
+    ) -> PumpStatus {
+        if !self.loop_running {
+            self.loop_running = true;
+
+            // Run the initial loop iteration.
+            self.single_iteration(&mut app, StartCause::Init);
+        }
+
+        if self.window_target.exit.get() {
+            self.loop_running = false;
+            // TODO: other exit codes
+            return PumpStatus::Exit(0);
+        }
 
+        let start = Instant::now();
+        let timeout = {
             let requested_resume = match self.window_target.control_flow() {
-                ControlFlow::Poll => {
-                    start_cause = StartCause::Poll;
-                    continue;
-                },
+                ControlFlow::Poll => Some(Duration::ZERO),
                 ControlFlow::Wait => None,
-                ControlFlow::WaitUntil(instant) => Some(instant),
+                ControlFlow::WaitUntil(instant) => Some(instant.saturating_duration_since(start)),
             };
+            min_timeout(timeout, requested_resume)
+        };
 
-            // Re-using wake socket caused extra wake events before because there were leftover
-            // timeouts, and then new timeouts were added each time a spurious timeout expired.
-            let timeout_socket = TimeSocket::open().unwrap();
-
+        if let Some(timeout) = timeout {
             self.window_target
                 .event_socket
-                .subscribe(timeout_socket.0.fd(), EventSource::Time, EventFlags::READ)
-                .unwrap();
-
-            let start = Instant::now();
-            if let Some(instant) = requested_resume {
-                let mut time = timeout_socket.current_time().unwrap();
-
-                if let Some(duration) = instant.checked_duration_since(start) {
-                    time.tv_sec += duration.as_secs() as i64;
-                    time.tv_nsec += duration.subsec_nanos() as c_long;
-                    // Normalize timespec so tv_nsec is not greater than one second.
-                    while time.tv_nsec >= 1_000_000_000 {
-                        time.tv_sec += 1;
-                        time.tv_nsec -= 1_000_000_000;
-                    }
-                }
+                .subscribe(
+                    EVENT_TIMEOUT_ID,
+                    UserData::from_user_data(timeout.as_millis() as usize),
+                    EventFlags::READ,
+                )
+                .expect("failed to register EVENT_TIMEOUT_ID")
+        }
 
-                timeout_socket.timeout(&time).unwrap();
+        // Wait for event if needed.
+        let event = loop {
+            match self.window_target.event_socket.next_event() {
+                Ok(event) => break event,
+                Err(err) if err.is_interrupt() => continue,
+                Err(err) => {
+                    panic!("failed to read event: {err}");
+                },
             }
+        };
 
-            // Wait for event if needed.
-            let event = loop {
-                match self.window_target.event_socket.next_event() {
-                    Ok(event) => break event,
-                    Err(err) if err.is_interrupt() => continue,
-                    Err(err) => {
-                        return Err(os_error!(format!("failed to read event: {err}")).into());
-                    },
+        if timeout.is_some() && event.fd == EVENT_TIMEOUT_ID {
+            // NB: EVENT_TIMEOUT_ID is not a regular event ID.
+            // Here nothing is happened yet.
+            return PumpStatus::Continue;
+        }
+
+        // Normal window event or spurious timeout.
+        let cause = match self.window_target.control_flow() {
+            ControlFlow::Poll => StartCause::Poll,
+            ControlFlow::Wait => StartCause::WaitCancelled { start, requested_resume: None },
+            ControlFlow::WaitUntil(deadline) => {
+                if Instant::now() < deadline {
+                    StartCause::WaitCancelled { start, requested_resume: Some(deadline) }
+                } else {
+                    StartCause::ResumeTimeReached { start, requested_resume: deadline }
                 }
-            };
+            },
+        };
 
-            // TODO: handle spurious wakeups (redraw caused wakeup but redraw already handled)
-            match requested_resume {
-                Some(requested_resume)
-                    if event.fd == timeout_socket.0.fd()
-                        && matches!(event.user_data, EventSource::Time) =>
-                {
-                    // If the event is from the special timeout socket, report that resume
-                    // time was reached.
-                    start_cause = StartCause::ResumeTimeReached { start, requested_resume };
-                },
-                _ => {
-                    // Normal window event or spurious timeout.
-                    start_cause = StartCause::WaitCancelled { start, requested_resume };
-                },
-            }
-        }
+        // Do actual event processing
+        self.single_iteration(&mut app, cause);
 
-        Ok(())
+        PumpStatus::Continue
     }
 
     pub fn window_target(&self) -> &dyn RootActiveEventLoop {
@@ -802,3 +841,10 @@ impl rwh_06::HasDisplayHandle for OwnedDisplayHandle {
 
 #[derive(Default, Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub struct PlatformSpecificEventLoopAttributes {}
+
+/// Returns the minimum `Option<Duration>`, taking into account that `None`
+/// equates to an infinite timeout, not a zero timeout (so can't just use
+/// `Option::min`)
+fn min_timeout(a: Option<Duration>, b: Option<Duration>) -> Option<Duration> {
+    a.map_or(b, |a_timeout| b.map_or(Some(a_timeout), |b_timeout| Some(a_timeout.min(b_timeout))))
+}

winit-orbital/src/lib.rs

@@ -66,6 +66,7 @@ impl TimeSocket {
     }
 
     // Read current time.
+    #[allow(unused)]
     fn current_time(&self) -> Result<TimeSpec> {
         let mut timespec: libredox::data::TimeSpec = unsafe { mem::zeroed() };
         let timespec_bytes = unsafe {

winit/examples/pump_events.rs

@@ -1,7 +1,14 @@
 #![allow(clippy::single_match)]
 
 // Limit this example to only compatible platforms.
-#[cfg(any(windows_platform, macos_platform, x11_platform, wayland_platform, android_platform,))]
+#[cfg(any(
+    windows_platform,
+    macos_platform,
+    x11_platform,
+    wayland_platform,
+    android_platform,
+    orbital_platform,
+))]
 fn main() -> std::process::ExitCode {
     use std::process::ExitCode;
     use std::thread::sleep;
@@ -81,7 +88,7 @@ fn main() -> std::process::ExitCode {
     }
 }
 
-#[cfg(any(ios_platform, web_platform, orbital_platform))]
+#[cfg(any(ios_platform, web_platform))]
 fn main() {
     panic!("This platform doesn't support pump_events.")
 }

winit/src/changelog/unreleased.md

@@ -45,6 +45,7 @@ changelog entry.
 - Add `keyboard` support for OpenHarmony.
 - On iOS, add Apple Pencil support with force, altitude, and azimuth data.
 - On Redox, add support for missing keyboard scancodes.
+- On Redox, add support for `EventLoopExtPumpEvents::pump_app_events`.
 - Implement `Send` and `Sync` for `OwnedDisplayHandle`.
 - Use new macOS 15 cursors for resize icons.
 - On Android, added scancode conversions for more obscure key codes.

winit/src/event_loop.rs

@@ -326,6 +326,7 @@ impl AsRawFd for EventLoop {
     windows_platform,
     macos_platform,
     android_platform,
+    orbital_platform,
     x11_platform,
     wayland_platform,
     docsrs,

winit/src/lib.rs

@@ -269,7 +269,7 @@
 //! [`raw_window_handle`]: ./window/struct.Window.html#method.raw_window_handle
 //! [`raw_display_handle`]: ./window/struct.Window.html#method.raw_display_handle
 //! [`EventLoopExtPumpEvents::pump_app_events()`]: crate::event_loop::pump_events::EventLoopExtPumpEvents::pump_app_events()
-//! [^1]: `EventLoopExtPumpEvents::pump_app_events()` is only available on Windows, macOS, Android, X11 and Wayland.
+//! [^1]: `EventLoopExtPumpEvents::pump_app_events()` is only available on Windows, macOS, Android, Redox, X11 and Wayland.
 
 #![deny(rust_2018_idioms)]
 #![deny(rustdoc::broken_intra_doc_links)]