display_utils/
controller.rs

1// Copyright 2021 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5use anyhow::Context;
6use display_types::IMAGE_TILING_TYPE_LINEAR;
7
8use fidl::endpoints::ClientEnd;
9use fidl_fuchsia_hardware_display::{
10    self as display, CoordinatorListenerRequest, LayerId as FidlLayerId,
11};
12use fidl_fuchsia_hardware_display_types::{self as display_types};
13use fuchsia_async::{DurationExt as _, TimeoutExt as _};
14use fuchsia_component::client::Service;
15use fuchsia_sync::RwLock;
16use futures::channel::mpsc;
17use futures::{TryFutureExt, TryStreamExt, future};
18use std::fmt;
19use std::sync::Arc;
20
21use crate::INVALID_EVENT_ID;
22use crate::config::{DisplayConfig, LayerConfig};
23use crate::error::{ConfigError, Error, Result};
24use crate::types::{
25    BufferCollectionId, ClientPriority, DisplayId, DisplayInfo, Event, EventId, ImageId, LayerId,
26};
27
28const TIMEOUT: zx::MonotonicDuration = zx::MonotonicDuration::from_seconds(2);
29
30/// Client abstraction for the `fuchsia.hardware.display.Coordinator` protocol. Instances can be
31/// safely cloned and passed across threads.
32#[derive(Clone)]
33pub struct Coordinator {
34    inner: Arc<RwLock<CoordinatorInner>>,
35}
36
37struct CoordinatorInner {
38    displays: Vec<DisplayInfo>,
39    proxy: display::CoordinatorProxy,
40    listener_requests: Option<display::CoordinatorListenerRequestStream>,
41
42    // All subscribed vsync listeners and their optional ID filters.
43    vsync_listeners: Vec<(mpsc::UnboundedSender<VsyncEvent>, Option<DisplayId>)>,
44
45    // Simple counter to generate client-assigned integer identifiers.
46    id_counter: u64,
47
48    // Generate stamps for `commit_config()`.
49    stamp_counter: u64,
50}
51
52/// A vsync event payload.
53#[derive(Debug)]
54pub struct VsyncEvent {
55    /// The ID of the display that generated the vsync event.
56    pub id: DisplayId,
57
58    /// The monotonic timestamp of the vsync event.
59    pub timestamp: zx::MonotonicInstant,
60
61    /// The stamp of the latest fully applied display configuration.
62    pub config: display::ConfigStamp,
63}
64
65impl Coordinator {
66    /// Establishes a connection to the display-coordinator device and initialize a `Coordinator`
67    /// instance with the initial set of available displays. The returned `Coordinator` will
68    /// maintain FIDL connection to the underlying device as long as it is alive or the connection
69    /// is closed by the peer.
70    ///
71    /// Returns an error if
72    /// - No display-coordinator device is found within `TIMEOUT`.
73    /// - An initial OnDisplaysChanged event is not received from the display driver within
74    ///   `TIMEOUT` seconds.
75    ///
76    /// Current limitations:
77    ///   - This function connects to the first display-coordinator device that it observes. It
78    ///   currently does not support selection of a specific device if multiple display-coordinator
79    ///   devices are present.
80    // TODO(https://fxbug.dev/42168593): This will currently result in an error if no displays are present on
81    // the system (or if one is not attached within `TIMEOUT`). It wouldn't be neceesary to rely on
82    // a timeout if the display driver sent en event with no displays.
83    pub async fn init(client_priority: ClientPriority) -> Result<Coordinator> {
84        let service_proxy = Service::open(display::ServiceMarker)
85            .context("failed to open display Service")
86            .map_err(Error::DeviceConnectionError)?
87            .watch_for_any()
88            .map_err(Error::DeviceConnectionError)
89            .on_timeout(TIMEOUT.after_now(), || Err(Error::DeviceNotFound))
90            .await?;
91
92        let provider_proxy = service_proxy
93            .connect_to_provider()
94            .context("failed to connect to FIDL provider")
95            .map_err(|x| Error::DeviceConnectionError(x.into()))?;
96
97        let (coordinator_proxy, coordinator_server_end) =
98            fidl::endpoints::create_proxy::<display::CoordinatorMarker>();
99        let (coordinator_listener_client_end, coordinator_listener_requests) =
100            fidl::endpoints::create_request_stream::<display::CoordinatorListenerMarker>();
101
102        // TODO(https://fxbug.dev/42075865): Consider supporting virtcon client
103        // connections.
104        let payload = display::ProviderOpenCoordinatorRequest {
105            coordinator: Some(coordinator_server_end),
106            coordinator_listener: Some(coordinator_listener_client_end),
107            priority: Some(client_priority.into()),
108            __source_breaking: fidl::marker::SourceBreaking,
109        };
110        let () =
111            provider_proxy.open_coordinator(payload).await?.map_err(zx::Status::err_from_raw)?;
112
113        Self::init_with_proxy_and_listener_requests(
114            coordinator_proxy,
115            coordinator_listener_requests,
116        )
117        .await
118    }
119
120    /// Initialize a `Coordinator` instance from pre-established Coordinator and
121    /// CoordinatorListener channels.
122    ///
123    /// Returns an error if
124    /// - An initial OnDisplaysChanged event is not received from the display driver within
125    ///   `TIMEOUT` seconds.
126    // TODO(https://fxbug.dev/42168593): This will currently result in an error if no displays are
127    // present on the system (or if one is not attached within `TIMEOUT`). It wouldn't be neceesary
128    // to rely on a timeout if the display driver sent en event with no displays.
129    pub async fn init_with_proxy_and_listener_requests(
130        coordinator_proxy: display::CoordinatorProxy,
131        mut listener_requests: display::CoordinatorListenerRequestStream,
132    ) -> Result<Coordinator> {
133        let displays = wait_for_initial_displays(&mut listener_requests)
134            .on_timeout(TIMEOUT.after_now(), || Err(Error::NoDisplays))
135            .await?
136            .into_iter()
137            .map(DisplayInfo)
138            .collect::<Vec<_>>();
139        Ok(Coordinator {
140            inner: Arc::new(RwLock::new(CoordinatorInner {
141                proxy: coordinator_proxy,
142                listener_requests: Some(listener_requests),
143                displays,
144                vsync_listeners: Vec::new(),
145                id_counter: 0,
146                stamp_counter: 0,
147            })),
148        })
149    }
150
151    /// Returns a copy of the list of displays that are currently known to be present on the system.
152    pub fn displays(&self) -> Vec<DisplayInfo> {
153        self.inner.read().displays.clone()
154    }
155
156    /// Returns a clone of the underlying FIDL client proxy.
157    ///
158    /// Note: This can be helpful to prevent holding the inner RwLock when awaiting a chained FIDL
159    /// call over a proxy.
160    pub fn proxy(&self) -> display::CoordinatorProxy {
161        self.inner.read().proxy.clone()
162    }
163
164    /// Registers a channel to listen to vsync events.
165    pub fn add_vsync_listener(
166        &self,
167        id: Option<DisplayId>,
168    ) -> Result<mpsc::UnboundedReceiver<VsyncEvent>> {
169        // TODO(armansito): Switch to a bounded channel instead.
170        let (sender, receiver) = mpsc::unbounded::<VsyncEvent>();
171        self.inner.write().vsync_listeners.push((sender, id));
172        Ok(receiver)
173    }
174
175    /// Returns a Future that represents the FIDL event handling task. Once scheduled on an
176    /// executor, this task will continuously handle incoming FIDL events from the display stack
177    /// and the returned Future will not terminate until the FIDL channel is closed.
178    ///
179    /// This task can be scheduled safely on any thread.
180    pub async fn handle_events(&self) -> Result<()> {
181        let inner = self.inner.clone();
182        let mut events = inner.write().listener_requests.take().ok_or(Error::AlreadyRequested)?;
183        while let Some(msg) = events.try_next().await? {
184            match msg {
185                CoordinatorListenerRequest::OnDisplaysChanged {
186                    added,
187                    removed,
188                    control_handle: _,
189                } => {
190                    let removed =
191                        removed.into_iter().map(|id| id.into()).collect::<Vec<DisplayId>>();
192                    inner.read().handle_displays_changed(added, removed);
193                }
194                CoordinatorListenerRequest::OnVsync {
195                    display_id,
196                    timestamp,
197                    displayed_config_stamp,
198                    cookie,
199                    control_handle: _,
200                } => {
201                    inner.write().handle_vsync(
202                        display_id.into(),
203                        timestamp,
204                        displayed_config_stamp,
205                        cookie,
206                    )?;
207                }
208                _ => continue,
209            }
210        }
211        Ok(())
212    }
213
214    /// Allocates a new virtual hardware layer that is not associated with any display and has no
215    /// configuration.
216    pub async fn create_layer(&self) -> Result<LayerId> {
217        let layer_id = self.inner.write().next_free_layer_id()?;
218        self.proxy().create_layer(&layer_id.into()).await?.map_err(zx::Status::err_from_raw)?;
219        Ok(layer_id)
220    }
221
222    /// Creates and registers a zircon event with the display driver. The returned event can be
223    /// used as a fence in a display configuration.
224    pub fn create_event(&self) -> Result<Event> {
225        let event = zx::Event::create();
226        let remote = event.duplicate_handle(zx::Rights::SAME_RIGHTS)?;
227        let id = self.inner.write().next_free_event_id()?;
228
229        self.inner.read().proxy.import_event(zx::Event::from(remote), &id.into())?;
230        Ok(Event::new(id, event))
231    }
232
233    /// Apply a display configuration. The client is expected to receive a vsync event once the
234    /// configuration is successfully applied. Returns an error if the FIDL message cannot be sent.
235    pub async fn commit_config(
236        &self,
237        configs: &[DisplayConfig],
238    ) -> std::result::Result<u64, ConfigError> {
239        let proxy = self.proxy();
240        for config in configs {
241            proxy.set_display_layers(
242                &config.id.into(),
243                &config.layers.iter().map(|l| l.id.into()).collect::<Vec<FidlLayerId>>(),
244            )?;
245            for layer in &config.layers {
246                match &layer.config {
247                    LayerConfig::Color { color, display_destination } => {
248                        let fidl_color = fidl_fuchsia_hardware_display_types::Color::from(color);
249                        proxy.set_layer_color_config(
250                            &layer.id.into(),
251                            &fidl_color,
252                            display_destination,
253                        )?;
254                    }
255                    LayerConfig::Primary { image_id, image_metadata, unblock_event, alpha } => {
256                        proxy.set_layer_primary_config(&layer.id.into(), &image_metadata)?;
257                        if let Some(alpha_config) = alpha {
258                            proxy.set_layer_primary_alpha(
259                                &layer.id.into(),
260                                alpha_config.mode,
261                                alpha_config.val,
262                            )?;
263                        }
264                        proxy.set_layer_image2(
265                            &layer.id.into(),
266                            &(*image_id).into(),
267                            &unblock_event.unwrap_or(INVALID_EVENT_ID).into(),
268                        )?;
269                    }
270                }
271            }
272        }
273
274        let result = proxy.check_config().await?;
275        if result != display_types::ConfigResult::Ok {
276            return Err(ConfigError::invalid(result));
277        }
278
279        let config_stamp = self.inner.write().next_config_stamp().unwrap();
280        let payload = fidl_fuchsia_hardware_display::CoordinatorCommitConfigRequest {
281            stamp: Some(fidl_fuchsia_hardware_display::ConfigStamp { value: config_stamp }),
282            ..Default::default()
283        };
284        match proxy.commit_config(payload) {
285            Ok(()) => Ok(config_stamp),
286            Err(err) => Err(ConfigError::from(err)),
287        }
288    }
289
290    /// Get the config stamp value of the most recent applied config in
291    /// `commit_config`. Returns an error if the FIDL message cannot be sent.
292    pub async fn get_recent_committed_config_stamp(&self) -> std::result::Result<u64, Error> {
293        let proxy = self.proxy();
294        let response = proxy.get_latest_committed_config_stamp().await?;
295        Ok(response.value)
296    }
297
298    /// Import a sysmem buffer collection. The returned `BufferCollectionId` can be used in future
299    /// API calls to refer to the imported collection.
300    pub(crate) async fn import_buffer_collection(
301        &self,
302        token: ClientEnd<fidl_fuchsia_sysmem2::BufferCollectionTokenMarker>,
303    ) -> Result<BufferCollectionId> {
304        let id = self.inner.write().next_free_collection_id()?;
305        let proxy = self.proxy();
306
307        // First import the token.
308        proxy
309            .import_buffer_collection(&id.into(), token)
310            .await?
311            .map_err(zx::Status::err_from_raw)?;
312
313        // Tell the driver to assign any device-specific constraints.
314        // TODO(https://fxbug.dev/42166207): These fields are effectively unused except for `type` in the case
315        // of IMAGE_TYPE_CAPTURE.
316        proxy
317            .set_buffer_collection_constraints(
318                &id.into(),
319                &display_types::ImageBufferUsage { tiling_type: IMAGE_TILING_TYPE_LINEAR },
320            )
321            .await?
322            .map_err(zx::Status::err_from_raw)?;
323        Ok(id)
324    }
325
326    /// Notify the display driver to release its handle on a previously imported buffer collection.
327    pub(crate) fn release_buffer_collection(&self, id: BufferCollectionId) -> Result<()> {
328        self.inner.read().proxy.release_buffer_collection(&id.into()).map_err(Error::from)
329    }
330
331    /// Register a sysmem buffer collection backed image to the display driver.
332    pub(crate) async fn import_image(
333        &self,
334        collection_id: BufferCollectionId,
335        image_id: ImageId,
336        image_metadata: display_types::ImageMetadata,
337    ) -> Result<()> {
338        self.proxy()
339            .import_image(
340                &image_metadata,
341                &collection_id.into(),
342                0, // buffer_index
343                &image_id.into(),
344            )
345            .await?
346            .map_err(zx::Status::err_from_raw)?;
347        Ok(())
348    }
349}
350
351// fmt::Debug implementation to allow a `Coordinator` instance to be used with a debug format
352// specifier. We use a custom implementation as not all `Coordinator` members derive fmt::Debug.
353impl fmt::Debug for Coordinator {
354    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
355        f.debug_struct("Coordinator").field("displays", &self.displays()).finish()
356    }
357}
358
359impl CoordinatorInner {
360    fn next_free_collection_id(&mut self) -> Result<BufferCollectionId> {
361        self.id_counter = self.id_counter.checked_add(1).ok_or(Error::IdsExhausted)?;
362        Ok(BufferCollectionId(self.id_counter))
363    }
364
365    fn next_free_event_id(&mut self) -> Result<EventId> {
366        self.id_counter = self.id_counter.checked_add(1).ok_or(Error::IdsExhausted)?;
367        Ok(EventId(self.id_counter))
368    }
369
370    fn next_free_layer_id(&mut self) -> Result<LayerId> {
371        self.id_counter = self.id_counter.checked_add(1).ok_or(Error::IdsExhausted)?;
372        Ok(LayerId(self.id_counter))
373    }
374
375    fn next_config_stamp(&mut self) -> Result<u64> {
376        self.stamp_counter = self.stamp_counter.checked_add(1).ok_or(Error::IdsExhausted)?;
377        Ok(self.stamp_counter)
378    }
379
380    fn handle_displays_changed(&self, _added: Vec<display::Info>, _removed: Vec<DisplayId>) {
381        // TODO(armansito): update the displays list and notify clients. Terminate vsync listeners
382        // that are attached to a removed display.
383    }
384
385    fn handle_vsync(
386        &mut self,
387        display_id: DisplayId,
388        timestamp: zx::MonotonicInstant,
389        displayed_config_stamp: display::ConfigStamp,
390        cookie: display::VsyncAckCookie,
391    ) -> Result<()> {
392        if cookie.value != 0 {
393            self.proxy.acknowledge_vsync(cookie.value)?;
394        }
395
396        let mut listeners_to_remove = Vec::new();
397        for (pos, (sender, filter)) in self.vsync_listeners.iter().enumerate() {
398            // Skip the listener if it has a filter that does not match `display_id`.
399            if filter.as_ref().map_or(false, |id| *id != display_id) {
400                continue;
401            }
402            let payload = VsyncEvent { id: display_id, timestamp, config: displayed_config_stamp };
403            if let Err(e) = sender.unbounded_send(payload) {
404                if e.is_disconnected() {
405                    listeners_to_remove.push(pos);
406                } else {
407                    return Err(e.into());
408                }
409            }
410        }
411
412        // Clean up disconnected listeners.
413        listeners_to_remove.into_iter().for_each(|pos| {
414            self.vsync_listeners.swap_remove(pos);
415        });
416
417        Ok(())
418    }
419}
420
421// Waits for a single fuchsia.hardware.display.Coordinator.OnDisplaysChanged event and returns the
422// reported displays. By API contract, this event will fire at least once upon initial channel
423// connection if any displays are present. If no displays are present, then the returned Future
424// will not resolve until a display is plugged in.
425async fn wait_for_initial_displays(
426    listener_requests: &mut display::CoordinatorListenerRequestStream,
427) -> Result<Vec<display::Info>> {
428    let mut stream = listener_requests.try_filter_map(|event| match event {
429        CoordinatorListenerRequest::OnDisplaysChanged { added, removed: _, control_handle: _ } => {
430            future::ok(Some(added))
431        }
432        _ => future::ok(None),
433    });
434    stream.try_next().await?.ok_or(Error::NoDisplays)
435}
436
437#[cfg(test)]
438mod tests {
439    use super::{Coordinator, DisplayId, VsyncEvent};
440    use anyhow::{Context, Result, format_err};
441    use display_mocks::{MockCoordinator, create_proxy_and_mock};
442    use fidl_fuchsia_hardware_display as display;
443    use fidl_fuchsia_hardware_display_types as display_types;
444    use fuchsia_async::TestExecutor;
445    use futures::task::Poll;
446    use futures::{FutureExt, StreamExt, pin_mut, select};
447    use googletest::{assert_that, expect_eq, expect_that, gtest, matchers};
448
449    async fn init_with_proxy_and_listener_requests(
450        coordinator_proxy: display::CoordinatorProxy,
451        listener_requests: display::CoordinatorListenerRequestStream,
452    ) -> Result<Coordinator> {
453        Coordinator::init_with_proxy_and_listener_requests(coordinator_proxy, listener_requests)
454            .await
455            .context("failed to initialize Coordinator")
456    }
457
458    // Returns a Coordinator and a connected mock FIDL server. This function sets up the initial
459    // "OnDisplaysChanged" event with the given list of `displays`, which `Coordinator` requires
460    // before it can resolve its initialization Future.
461    async fn init_with_displays(
462        displays: &[display::Info],
463    ) -> Result<(Coordinator, MockCoordinator)> {
464        let (coordinator_proxy, listener_requests, mut mock) = create_proxy_and_mock()?;
465        mock.assign_displays(displays.to_vec())?;
466
467        Ok((
468            init_with_proxy_and_listener_requests(coordinator_proxy, listener_requests).await?,
469            mock,
470        ))
471    }
472
473    #[gtest]
474    #[fuchsia::test]
475    async fn test_init_fails_with_no_device_dir() {
476        let result = Coordinator::init(crate::types::ClientPriority(300)).await;
477        expect_that!(&result, matchers::err(matchers::anything()));
478    }
479
480    #[gtest]
481    #[fuchsia::test]
482    async fn test_init_with_no_displays() -> Result<()> {
483        let (coordinator_proxy, listener_requests, mut mock) = create_proxy_and_mock()?;
484        mock.assign_displays([].to_vec())?;
485
486        let coordinator =
487            init_with_proxy_and_listener_requests(coordinator_proxy, listener_requests).await?;
488        expect_that!(&coordinator.displays(), matchers::is_empty());
489
490        Ok(())
491    }
492
493    // TODO(https://fxbug.dev/42075852): We should have an automated test verifying that
494    // the service provided by driver framework can be opened correctly.
495
496    #[gtest]
497    #[fuchsia::test]
498    async fn test_init_with_displays() -> Result<()> {
499        let displays = [
500            display::Info {
501                id: display_types::DisplayId { value: 1 },
502                modes: Vec::new(),
503                pixel_format: Vec::new(),
504                manufacturer_name: "Foo".to_string(),
505                monitor_name: "what".to_string(),
506                monitor_serial: "".to_string(),
507                horizontal_size_mm: 0,
508                vertical_size_mm: 0,
509                using_fallback_size: false,
510                max_layer_count: 1,
511            },
512            display::Info {
513                id: display_types::DisplayId { value: 2 },
514                modes: Vec::new(),
515                pixel_format: Vec::new(),
516                manufacturer_name: "Bar".to_string(),
517                monitor_name: "who".to_string(),
518                monitor_serial: "".to_string(),
519                horizontal_size_mm: 0,
520                vertical_size_mm: 0,
521                using_fallback_size: false,
522                max_layer_count: 1,
523            },
524        ]
525        .to_vec();
526        let (coordinator_proxy, listener_requests, mut mock) = create_proxy_and_mock()?;
527        mock.assign_displays(displays.clone())?;
528
529        let coordinator =
530            init_with_proxy_and_listener_requests(coordinator_proxy, listener_requests).await?;
531        expect_eq!(coordinator.displays().len(), 2);
532        expect_eq!(coordinator.displays()[0].0, displays[0]);
533        expect_eq!(coordinator.displays()[1].0, displays[1]);
534
535        Ok(())
536    }
537
538    #[gtest]
539    #[test]
540    fn test_vsync_listener_single() -> Result<()> {
541        // Drive an executor directly for this test to avoid having to rely on timeouts for cases
542        // in which no events are received.
543        let mut executor = TestExecutor::new();
544        let (coordinator, mock) = executor.run_singlethreaded(init_with_displays(&[]))?;
545        let mut vsync = coordinator.add_vsync_listener(None)?;
546
547        const ID: DisplayId = DisplayId(1);
548        const STAMP: display::ConfigStamp = display::ConfigStamp { value: 1 };
549        let event_handlers = async {
550            select! {
551                event = vsync.next() => event.ok_or_else(|| format_err!("did not receive vsync event")),
552                result = coordinator.handle_events().fuse() => {
553                    result.context("FIDL event handler failed")?;
554                    Err(format_err!("FIDL event handler completed before client vsync event"))
555                },
556            }
557        };
558        pin_mut!(event_handlers);
559
560        // Send a single event.
561        mock.emit_vsync_event(ID.0, STAMP)?;
562        let vsync_event = executor.run_until_stalled(&mut event_handlers);
563        assert_that!(&vsync_event, matchers::matches_pattern!(Poll::Ready(matchers::anything())));
564        let Poll::Ready(result) = vsync_event else { unreachable!() };
565        let VsyncEvent { id, config, .. } = result.unwrap();
566        expect_eq!(id, ID);
567        expect_eq!(config, STAMP);
568
569        Ok(())
570    }
571
572    #[gtest]
573    #[test]
574    fn test_vsync_listener_multiple() -> Result<()> {
575        // Drive an executor directly for this test to avoid having to rely on timeouts for cases
576        // in which no events are received.
577        let mut executor = TestExecutor::new();
578        let (coordinator, mock) = executor.run_singlethreaded(init_with_displays(&[]))?;
579        let mut vsync = coordinator.add_vsync_listener(None)?;
580
581        let fidl_server = coordinator.handle_events().fuse();
582        pin_mut!(fidl_server);
583
584        const ID1: DisplayId = DisplayId(1);
585        const ID2: DisplayId = DisplayId(2);
586        const STAMP: display::ConfigStamp = display::ConfigStamp { value: 1 };
587
588        // Queue multiple events.
589        mock.emit_vsync_event(ID1.0, STAMP)?;
590        mock.emit_vsync_event(ID2.0, STAMP)?;
591        mock.emit_vsync_event(ID1.0, STAMP)?;
592
593        // Process the FIDL events. The FIDL server Future should not complete as it runs
594        // indefinitely.
595        let fidl_server_result = executor.run_until_stalled(&mut fidl_server);
596        assert_that!(fidl_server_result, matchers::matches_pattern!(Poll::Pending));
597
598        // Process the vsync listener.
599        let vsync_event = executor.run_until_stalled(&mut Box::pin(async { vsync.next().await }));
600        assert_that!(&vsync_event, matchers::matches_pattern!(Poll::Ready(matchers::anything())));
601        let Poll::Ready(Some(VsyncEvent { id, config, .. })) = vsync_event else { unreachable!() };
602        expect_eq!(id, ID1);
603        expect_eq!(config, STAMP);
604
605        let vsync_event = executor.run_until_stalled(&mut Box::pin(async { vsync.next().await }));
606        assert_that!(&vsync_event, matchers::matches_pattern!(Poll::Ready(matchers::anything())));
607        let Poll::Ready(Some(VsyncEvent { id, config, .. })) = vsync_event else { unreachable!() };
608        expect_eq!(id, ID2);
609        expect_eq!(config, STAMP);
610
611        let vsync_event = executor.run_until_stalled(&mut Box::pin(async { vsync.next().await }));
612        assert_that!(&vsync_event, matchers::matches_pattern!(Poll::Ready(matchers::anything())));
613        let Poll::Ready(Some(VsyncEvent { id, config, .. })) = vsync_event else { unreachable!() };
614        expect_eq!(id, ID1);
615        expect_eq!(config, STAMP);
616
617        Ok(())
618    }
619
620    #[gtest]
621    #[test]
622    fn test_vsync_listener_display_id_filter() -> Result<()> {
623        // Drive an executor directly for this test to avoid having to rely on timeouts for cases
624        // in which no events are received.
625        let mut executor = TestExecutor::new();
626        let (coordinator, mock) = executor.run_singlethreaded(init_with_displays(&[]))?;
627
628        const ID1: DisplayId = DisplayId(1);
629        const ID2: DisplayId = DisplayId(2);
630        const STAMP: display::ConfigStamp = display::ConfigStamp { value: 1 };
631
632        // Listen to events from ID2.
633        let mut vsync = coordinator.add_vsync_listener(Some(ID2))?;
634        let event_handlers = async {
635            select! {
636                event = vsync.next() => event.ok_or_else(|| format_err!("did not receive vsync event")),
637                result = coordinator.handle_events().fuse() => {
638                    result.context("FIDL event handler failed")?;
639                    Err(format_err!("FIDL event handler completed before client vsync event"))
640                },
641            }
642        };
643        pin_mut!(event_handlers);
644
645        // Event from ID1 should get filtered out and the client should not receive any events.
646        mock.emit_vsync_event(ID1.0, STAMP)?;
647        let vsync_event = executor.run_until_stalled(&mut event_handlers);
648        assert_that!(vsync_event, matchers::matches_pattern!(Poll::Pending));
649
650        // Event from ID2 should be received.
651        mock.emit_vsync_event(ID2.0, STAMP)?;
652        let vsync_event = executor.run_until_stalled(&mut event_handlers);
653        assert_that!(&vsync_event, matchers::matches_pattern!(Poll::Ready(matchers::anything())));
654        let Poll::Ready(result) = vsync_event else { unreachable!() };
655        let VsyncEvent { id, config, .. } = result.unwrap();
656        expect_eq!(id, ID2);
657        expect_eq!(config, STAMP);
658
659        Ok(())
660    }
661}
display_utils/controller.rs

display_utils/
controller.rs
