Auto merge of servo#21170 - gterzian:use_remote_event_task_source_for…

…_eventsource, r=jdm

Use remote-event task source in EventSource

<!-- Please describe your changes on the following line: -->
Follow up on servo#21126, this again 'changes nothing', but will be useful for servo#21114 in the context of servo#21111.

Trying to break up work into smaller PR's ;)

---
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- [ ] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix servo#21112 (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/script/dom/eventsource.rs

@@ -100,7 +100,7 @@ impl EventSourceContext {
         let global = event_source.global();
         let event_source = self.event_source.clone();
         // FIXME(nox): Why are errors silenced here?
-        let _ = global.networking_task_source().queue(
+        let _ = global.remote_event_task_source().queue(
             task!(announce_the_event_source_connection: move || {
                 let event_source = event_source.root();
                 if event_source.ready_state.get() != ReadyState::Closed {
@@ -121,7 +121,7 @@ impl EventSourceContext {
         let global = event_source.global();
         let event_source = self.event_source.clone();
         // FIXME(nox): Why are errors silenced here?
-        let _ = global.networking_task_source().queue(
+        let _ = global.remote_event_task_source().queue(
             task!(fail_the_event_source_connection: move || {
                 let event_source = event_source.root();
                 if event_source.ready_state.get() != ReadyState::Closed {
@@ -145,7 +145,7 @@ impl EventSourceContext {
         let action_sender = self.action_sender.clone();
         let global = event_source.global();
         // FIXME(nox): Why are errors silenced here?
-        let _ = global.networking_task_source().queue(
+        let _ = global.remote_event_task_source().queue(
             task!(reestablish_the_event_source_onnection: move || {
                 let event_source = trusted_event_source.root();
 
@@ -242,7 +242,7 @@ impl EventSourceContext {
         let event_source = self.event_source.clone();
         let event = Trusted::new(&*event);
         // FIXME(nox): Why are errors silenced here?
-        let _ = global.networking_task_source().queue(
+        let _ = global.remote_event_task_source().queue(
             task!(dispatch_the_event_source_event: move || {
                 let event_source = event_source.root();
                 if event_source.ready_state.get() != ReadyState::Closed {
@@ -423,6 +423,7 @@ impl EventSource {
         self.request.borrow().clone().unwrap()
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-eventsource
     pub fn Constructor(global: &GlobalScope,
                        url: DOMString,
                        event_source_init: &EventSourceInit) -> Fallible<DomRoot<EventSource>> {
@@ -482,8 +483,6 @@ impl EventSource {
             data: String::new(),
             last_event_id: String::new(),
         };
-        // TODO: use the "remote event task source", and canceller.
-        // https://html.spec.whatwg.org/multipage/#remote-event-task-source
         let listener = NetworkListener {
             context: Arc::new(Mutex::new(context)),
             task_source: global.networking_task_source(),

components/script/dom/globalscope.rs

@@ -56,6 +56,7 @@ use task_source::TaskSourceName;
 use task_source::file_reading::FileReadingTaskSource;
 use task_source::networking::NetworkingTaskSource;
 use task_source::performance_timeline::PerformanceTimelineTaskSource;
+use task_source::remote_event::RemoteEventTaskSource;
 use time::{Timespec, get_time};
 use timers::{IsInterval, OneshotTimerCallback, OneshotTimerHandle};
 use timers::{OneshotTimers, TimerCallback};
@@ -390,7 +391,7 @@ impl GlobalScope {
     }
 
     /// `ScriptChan` to send messages to the networking task source of
-    /// this of this global scope.
+    /// this global scope.
     pub fn networking_task_source(&self) -> NetworkingTaskSource {
         if let Some(window) = self.downcast::<Window>() {
             return window.networking_task_source();
@@ -401,6 +402,18 @@ impl GlobalScope {
         unreachable!();
     }
 
+    /// `ScriptChan` to send messages to the remote-event task source of
+    /// this global scope.
+    pub fn remote_event_task_source(&self) -> RemoteEventTaskSource {
+        if let Some(window) = self.downcast::<Window>() {
+            return window.remote_event_task_source();
+        }
+        if let Some(worker) = self.downcast::<WorkerGlobalScope>() {
+            return worker.remote_event_task_source();
+        }
+        unreachable!();
+    }
+
     /// Evaluate JS code on this global scope.
     pub fn evaluate_js_on_global_with_result(
             &self, code: &str, rval: MutableHandleValue) -> bool {

components/script/dom/window.rs

@@ -115,6 +115,7 @@ use task_source::file_reading::FileReadingTaskSource;
 use task_source::history_traversal::HistoryTraversalTaskSource;
 use task_source::networking::NetworkingTaskSource;
 use task_source::performance_timeline::PerformanceTimelineTaskSource;
+use task_source::remote_event::RemoteEventTaskSource;
 use task_source::user_interaction::UserInteractionTaskSource;
 use time;
 use timers::{IsInterval, TimerCallback};
@@ -172,6 +173,8 @@ pub struct Window {
     file_reading_task_source: FileReadingTaskSource,
     #[ignore_malloc_size_of = "task sources are hard"]
     performance_timeline_task_source: PerformanceTimelineTaskSource,
+    #[ignore_malloc_size_of = "task sources are hard"]
+    remote_event_task_source: RemoteEventTaskSource,
     navigator: MutNullableDom<Navigator>,
     #[ignore_malloc_size_of = "Arc"]
     image_cache: Arc<ImageCache>,
@@ -358,6 +361,10 @@ impl Window {
         self.performance_timeline_task_source.clone()
     }
 
+    pub fn remote_event_task_source(&self) -> RemoteEventTaskSource {
+        self.remote_event_task_source.clone()
+    }
+
     pub fn main_thread_script_chan(&self) -> &Sender<MainThreadScriptMsg> {
         &self.script_chan.0
     }
@@ -1798,6 +1805,7 @@ impl Window {
         history_traversal_task_source: HistoryTraversalTaskSource,
         file_reading_task_source: FileReadingTaskSource,
         performance_timeline_task_source: PerformanceTimelineTaskSource,
+        remote_event_task_source: RemoteEventTaskSource,
         image_cache_chan: Sender<ImageCacheMsg>,
         image_cache: Arc<ImageCache>,
         resource_threads: ResourceThreads,
@@ -1850,6 +1858,7 @@ impl Window {
             history_traversal_task_source,
             file_reading_task_source,
             performance_timeline_task_source,
+            remote_event_task_source,
             image_cache_chan,
             image_cache,
             navigator: Default::default(),

components/script/dom/workerglobalscope.rs

@@ -46,6 +46,7 @@ use task::TaskCanceller;
 use task_source::file_reading::FileReadingTaskSource;
 use task_source::networking::NetworkingTaskSource;
 use task_source::performance_timeline::PerformanceTimelineTaskSource;
+use task_source::remote_event::RemoteEventTaskSource;
 use time::precise_time_ns;
 use timers::{IsInterval, TimerCallback};
 
@@ -385,6 +386,10 @@ impl WorkerGlobalScope {
         PerformanceTimelineTaskSource(self.script_chan(), self.pipeline_id())
     }
 
+    pub fn remote_event_task_source(&self) -> RemoteEventTaskSource {
+        RemoteEventTaskSource(self.script_chan(), self.pipeline_id())
+    }
+
     pub fn new_script_pair(&self) -> (Box<ScriptChan + Send>, Box<ScriptPort + Send>) {
         let dedicated = self.downcast::<DedicatedWorkerGlobalScope>();
         if let Some(dedicated) = dedicated {

components/script/script_thread.rs

@@ -121,6 +121,7 @@ use task_source::file_reading::FileReadingTaskSource;
 use task_source::history_traversal::HistoryTraversalTaskSource;
 use task_source::networking::NetworkingTaskSource;
 use task_source::performance_timeline::PerformanceTimelineTaskSource;
+use task_source::remote_event::RemoteEventTaskSource;
 use task_source::user_interaction::UserInteractionTaskSource;
 use time::{get_time, precise_time_ns, Tm};
 use url::Position;
@@ -436,6 +437,8 @@ pub struct ScriptThread {
 
     performance_timeline_task_sender: Box<ScriptChan>,
 
+    remote_event_task_sender: Box<ScriptChan>,
+
     /// A channel to hand out to threads that need to respond to a message from the script thread.
     control_chan: IpcSender<ConstellationControlMsg>,
 
@@ -850,6 +853,7 @@ impl ScriptThread {
             networking_task_sender: boxed_script_sender.clone(),
             file_reading_task_sender: boxed_script_sender.clone(),
             performance_timeline_task_sender: boxed_script_sender.clone(),
+            remote_event_task_sender: boxed_script_sender.clone(),
 
             history_traversal_task_source: HistoryTraversalTaskSource(chan),
 
@@ -1805,6 +1809,10 @@ impl ScriptThread {
         FileReadingTaskSource(self.file_reading_task_sender.clone(), pipeline_id)
     }
 
+    pub fn remote_event_task_source(&self, pipeline_id: PipelineId) -> RemoteEventTaskSource {
+        RemoteEventTaskSource(self.remote_event_task_sender.clone(), pipeline_id)
+    }
+
     /// Handles a request for the window title.
     fn handle_get_title_msg(&self, pipeline_id: PipelineId) {
         let document = match { self.documents.borrow().find_document(pipeline_id) } {
@@ -2113,6 +2121,7 @@ impl ScriptThread {
             HistoryTraversalTaskSource(history_sender.clone()),
             self.file_reading_task_source(incomplete.pipeline_id),
             self.performance_timeline_task_source(incomplete.pipeline_id).clone(),
+            self.remote_event_task_source(incomplete.pipeline_id),
             self.image_cache_channel.clone(),
             self.image_cache.clone(),
             self.resource_threads.clone(),

components/script/task_source/mod.rs

@@ -8,6 +8,7 @@ pub mod file_reading;
 pub mod history_traversal;
 pub mod networking;
 pub mod performance_timeline;
+pub mod remote_event;
 pub mod user_interaction;
 
 use dom::globalscope::GlobalScope;
@@ -26,7 +27,8 @@ pub enum TaskSourceName {
     HistoryTraversal,
     Networking,
     PerformanceTimeline,
-    UserInteraction
+    UserInteraction,
+    RemoteEvent
 }
 
 impl TaskSourceName {

components/script/task_source/remote_event.rs

@@ -0,0 +1,36 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use msg::constellation_msg::PipelineId;
+use script_runtime::{CommonScriptMsg, ScriptChan, ScriptThreadEventCategory};
+use task::{TaskCanceller, TaskOnce};
+use task_source::{TaskSource, TaskSourceName};
+
+#[derive(JSTraceable)]
+pub struct RemoteEventTaskSource(pub Box<ScriptChan + Send + 'static>, pub PipelineId);
+
+impl Clone for RemoteEventTaskSource {
+    fn clone(&self) -> RemoteEventTaskSource {
+        RemoteEventTaskSource(self.0.clone(), self.1.clone())
+    }
+}
+
+impl TaskSource for RemoteEventTaskSource {
+    const NAME: TaskSourceName = TaskSourceName::RemoteEvent;
+
+    fn queue_with_canceller<T>(
+        &self,
+        task: T,
+        canceller: &TaskCanceller,
+    ) -> Result<(), ()>
+    where
+        T: TaskOnce + 'static,
+    {
+        self.0.send(CommonScriptMsg::Task(
+            ScriptThreadEventCategory::NetworkEvent,
+            Box::new(canceller.wrap_task(task)),
+            Some(self.1),
+        ))
+    }
+}