Add Isolate.onExit.

sdk/lib/_internal/lib/isolate_helper.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library _isolate_helper;
 
 import 'dart:async';
 import 'dart:collection' show Queue, HashMap;
 import 'dart:isolate';
 import 'dart:_js_helper' show
@@ skipping 14 matching lines @@
 /**
  * Called by the compiler to support switching
  * between isolates when we get a callback from the DOM.
  */
 _callInIsolate(_IsolateContext isolate, Function function) {
   var result = isolate.eval(function);
   _globalState.topEventLoop.run();
   return result;
 }
 
-/// Marks entering a javascript async operation to keep the worker alive.
 /// Marks entering a JavaScript async operation to keep the worker alive.
 ///
 /// To be called by library code before starting an async operation controlled
 /// by the JavaScript event handler.
 ///
 /// Also call [leaveJsAsync] in all callback handlers marking the end of that
 /// async operation (also error handlers) so the worker can be released.
 ///
 /// These functions only has to be called for code that can be run from a
 /// worker-isolate (so not for general dom operations).
@@ skipping 217 matching lines @@
   /** Registry of weak receive ports currently active on this isolate. */
   final Set<int> weakPorts = new Set<int>();
 
   /** Holds isolate globals (statics and top-level properties). */
   // native object containing all globals of an isolate.
   final isolateStatics = JS_CREATE_ISOLATE();
 
   final RawReceivePortImpl controlPort = new RawReceivePortImpl._controlPort();
 
   final Capability pauseCapability = new Capability();
+  final Capability inspectCapability = new Capability();
 
   // TODO(lrn): Store these in single "PauseState" object, so they don't take
   // up as much room when not pausing.
   bool isPaused = false;
   List<_IsolateEvent> delayedEvents = [];
   Set<Capability> pauseTokens = new Set();
 
+  // Container with the "on exit" handler send-ports.
+  var doneHandlers;
+
   _IsolateContext() {
     this.registerWeak(controlPort._id, controlPort);
   }
 
   void addPause(Capability authentification, Capability resume) {
     if (pauseCapability != authentification) return;
     if (pauseTokens.add(resume) && !isPaused) {
       isPaused = true;
     }
     _updateGlobalState();
   }
 
   void removePause(Capability resume) {
     if (!isPaused) return;
     pauseTokens.remove(resume);
     if (pauseTokens.isEmpty) {
       while(delayedEvents.isNotEmpty) {
         _IsolateEvent event = delayedEvents.removeLast();
         _globalState.topEventLoop.prequeue(event);
       }
       isPaused = false;
     }
     _updateGlobalState();
   }
 
+  void addDoneListener(Capability inspect, SendPort response) {
+    if (inspectCapability != inspect) return;
+    if (doneHandlers == null) {
+      doneHandlers = [];
+    }
+    // If necessary, we can switch doneHandlers to a Set if it gets larget.

[floitsch, 2014/02/25 19:25:48]

larger.

+    // That is not expected to happen in practice.
+    if (doneHandlers.contains(response)) return;
+    doneHandlers.add(response);
+  }
+
   /**
    * Run [code] in the context of the isolate represented by [this].
    */
   dynamic eval(Function code) {
     var old = _globalState.currentContext;
     _globalState.currentContext = this;
     this._setGlobals();
     var result = null;
     try {
       result = code();
     } finally {
       _globalState.currentContext = old;
       if (old != null) old._setGlobals();
     }
     return result;
   }
 
   void _setGlobals() {
     JS_SET_CURRENT_ISOLATE(isolateStatics);
   }
 
   void handleControlMessage(message) {
     switch (message[0]) {
       case "pause":
         addPause(message[1], message[2]);
         break;
       case "resume":
         removePause(message[1]);
         break;
+      case 'ondone':
+        addDoneListener(message[1], message[2]);
+        break;
       default:
-        print("UNKOWN MESSAGE: $message");
+        print("UNKNOWN MESSAGE: $message");
     }
   }
 
   /** Looks up a port registered for this isolate. */
   RawReceivePortImpl lookup(int portId) => ports[portId];
 
   void _addRegistration(int portId, RawReceivePortImpl port) {
     if (ports.containsKey(portId)) {
       throw new Exception("Registry: ports must be registered only once.");
     }
     ports[portId] = port;
   }
 
   /** Registers a port on this isolate. */
   void register(int portId, RawReceivePortImpl port)  {
     _addRegistration(portId, port);
     _updateGlobalState();
   }
 
   /**
    * Registers a weak port on this isolate.
    *
    * The port does not keep the isolate active.
    */
   void registerWeak(int portId, RawReceivePortImpl port)  {
     weakPorts.add(portId);
     _addRegistration(portId, port);
   }
 
-  _updateGlobalState() {
+  void _updateGlobalState() {
     if (ports.length - weakPorts.length > 0 || isPaused) {
       _globalState.isolates[id] = this; // indicate this isolate is active
     } else {
-      _globalState.isolates.remove(id); // indicate this isolate is not active
+      _shutdown();
     }
   }
 
+  void _shutdown() {
+    _globalState.isolates.remove(id); // indicate this isolate is not active

[floitsch, 2014/02/25 19:25:48]

"I"ndicate ... active"."

+    // Send "done" event to all listeners. This must be done after deactivating
+    // the current isolate, or it may get events if listening to itself.
+    if (doneHandlers != null) {
+      for (SendPort port in doneHandlers) {
+        port.send(null);
+      }
+    }
+  }
+
   /** Unregister a port on this isolate. */
   void unregister(int portId) {
     ports.remove(portId);
     weakPorts.remove(portId);
     _updateGlobalState();
   }
 }
 
 /** Represent the event loop on a javascript thread (DOM or worker). */
 class _EventLoop {
@@ skipping 130 matching lines @@
 /// Note: IsolateNatives depends on _globalState which is only set up correctly
 /// when 'dart:isolate' has been imported.
 class IsolateNatives {
 
   static String thisScript = computeThisScript();
 
   /// Associates an ID with a native worker object.
   static final Expando<int> workerIds = new Expando<int>();
 
   /**
-   * The src url for the script tag that loaded this code. Used to create
+   * The src url for the script tag that loaded this Used to create

[floitsch, 2014/02/25 19:25:48]

missing ".".

    * JavaScript workers.
    */
   static String computeThisScript() {
     var currentScript = JS('', r'init.currentScript');
     if (currentScript != null) {
       return JS('String', 'String(#.src)', currentScript);
     }
     if (Primitives.isD8) return computeThisScriptD8();
     if (Primitives.isJsshell) return computeThisScriptJsshell();
     // A worker has no script tag - so get an url from a stack-trace.
@@ skipping 247 matching lines @@
   static void _startIsolate(Function topLevel,
                             List<String> args, message,
                             bool isSpawnUri,
                             bool startPaused,
                             SendPort replyTo) {
     _IsolateContext context = JS_CURRENT_ISOLATE_CONTEXT();
     Primitives.initializeStatics(context.id);
     // The isolate's port does not keep the isolate open.
     replyTo.send([_SPAWNED_SIGNAL,
                   context.controlPort.sendPort,
-                  context.pauseCapability]);
+                  context.pauseCapability,
+                  context.inspectCapability]);
 
     void runStartFunction() {
       if (!isSpawnUri) {
         topLevel(message);
       } else if (topLevel is _MainFunctionArgsMessage) {
         topLevel(args, message);
       } else if (topLevel is _MainFunctionArgs) {
         topLevel(args);
       } else {
         topLevel();
@@ skipping 721 matching lines @@
   }
 
   bool operator==(Object other) {
     if (identical(other, this)) return true;
     if (other is CapabilityImpl) {
       return identical(_id, other._id);
     }
     return false;
   }
 }