Unify dart:isolate.

lib/isolate/dart2js/isolateimpl.dart

Index: lib/isolate/dart2js/isolateimpl.dart
diff --git a/lib/isolate/dart2js/isolateimpl.dart b/lib/isolate/dart2js/isolateimpl.dart
deleted file mode 100644
index bec8d1799154b5cae0a48c49ea59dee9352e2b40..0000000000000000000000000000000000000000
--- a/lib/isolate/dart2js/isolateimpl.dart
+++ /dev/null
@@ -1,545 +0,0 @@
-// 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.
-
-/**
- * Concepts used here:
- *
- * "manager" - A manager contains one or more isolates, schedules their
- * execution, and performs other plumbing on their behalf.  The isolate
- * present at the creation of the manager is designated as its "root isolate".
- * A manager may, for example, be implemented on a web Worker.
- *
- * [_Manager] - State present within a manager (exactly once, as a global).
- *
- * [_ManagerStub] - A handle held within one manager that allows interaction
- * with another manager.  A target manager may be addressed by zero or more
- * [_ManagerStub]s.
- *
- */
-
-/**
- * A native object that is shared across isolates. This object is visible to all
- * isolates running under the same manager (either UI or background web worker).
- *
- * This is code that is intended to 'escape' the isolate boundaries in order to
- * implement the semantics of isolates in JavaScript. Without this we would have
- * been forced to implement more code (including the top-level event loop) in
- * JavaScript itself.
- */
-// TODO(eub, sigmund): move the "manager" to be entirely in JS.
-// Running any Dart code outside the context of an isolate gives it
-// the change to break the isolate abstraction.
-_Manager get _globalState() native "return \$globalState;";
-set _globalState(_Manager val) native "\$globalState = val;";
-
-void _fillStatics(context) native @"""
-  $globals = context.isolateStatics;
-  $static_init();
-""";
-
-ReceivePort _lazyPort;
-ReceivePort get _port() {
-  if (_lazyPort === null) {
-    _lazyPort = new ReceivePort();
-  }
-  return _lazyPort;
-}
-
-SendPort _spawnFunction(void topLevelFunction()) {
-  final name = _IsolateNatives._getJSFunctionName(topLevelFunction);
-  if (name == null) {
-    throw new UnsupportedOperationException(
-        "only top-level functions can be spawned.");
-  }
-  return _IsolateNatives._spawn(name, null, false);
-}
-
-SendPort _spawnUri(String uri) {
-  return _IsolateNatives._spawn(null, uri, false);
-}
-
-/** State associated with the current manager. See [globalState]. */
-// TODO(sigmund): split in multiple classes: global, thread, main-worker states?
-class _Manager {
-
-  /** Next available isolate id within this [_Manager]. */
-  int nextIsolateId = 0;
-
-  /** id assigned to this [_Manager]. */
-  int currentManagerId = 0;
-
-  /**
-   * Next available manager id. Only used by the main manager to assign a unique
-   * id to each manager created by it.
-   */
-  int nextManagerId = 1;
-
-  /** Context for the currently running [Isolate]. */
-  _IsolateContext currentContext = null;
-
-  /** Context for the root [Isolate] that first run in this [_Manager]. */
-  _IsolateContext rootContext = null;
-
-  /** The top-level event loop. */
-  _EventLoop topEventLoop;
-
-  /** Whether this program is running from the command line. */
-  bool fromCommandLine;
-
-  /** Whether this [_Manager] is running as a web worker. */
-  bool isWorker;
-
-  /** Whether we support spawning web workers. */
-  bool supportsWorkers;
-
-  /**
-   * Whether to use web workers when implementing isolates. Set to false for
-   * debugging/testing.
-   */
-  bool get useWorkers() => supportsWorkers;
-
-  /**
-   * Whether to use the web-worker JSON-based message serialization protocol. By
-   * default this is only used with web workers. For debugging, you can force
-   * using this protocol by changing this field value to [true].
-   */
-  bool get needSerialization() => useWorkers;
-
-  /**
-   * Registry of isolates. Isolates must be registered if, and only if, receive
-   * ports are alive.  Normally no open receive-ports means that the isolate is
-   * dead, but DOM callbacks could resurrect it.
-   */
-  Map<int, _IsolateContext> isolates;
-
-  /** Reference to the main [_Manager].  Null in the main [_Manager] itself. */
-  _ManagerStub mainManager;
-
-  /** Registry of active [_ManagerStub]s.  Only used in the main [_Manager]. */
-  Map<int, _ManagerStub> managers;
-
-  _Manager() {
-    _nativeDetectEnvironment();
-    topEventLoop = new _EventLoop();
-    isolates = new Map<int, _IsolateContext>();
-    managers = new Map<int, _ManagerStub>();
-    if (isWorker) {  // "if we are not the main manager ourself" is the intent.
-      mainManager = new _MainManagerStub();
-      _nativeInitWorkerMessageHandler();
-    }
-  }
-
-  void _nativeDetectEnvironment() native @"""
-    this.isWorker = $isWorker;
-    this.supportsWorkers = $supportsWorkers;
-    this.fromCommandLine = typeof(window) == 'undefined';
-  """;
-
-  void _nativeInitWorkerMessageHandler() native @"""
-    $globalThis.onmessage = function (e) {
-      _IsolateNatives._processWorkerMessage(this.mainManager, e);
-    }
-  """;
-  /*: TODO: check that _processWorkerMessage is not discarded while treeshaking.
-  """ {
-    _IsolateNatives._processWorkerMessage(null, null);
-  }
-  */
-
-
-  /** Close the worker running this code if all isolates are done. */
-  void maybeCloseWorker() {
-    if (isolates.isEmpty()) {
-      mainManager.postMessage(_serializeMessage({'command': 'close'}));
-    }
-  }
-}
-
-/** Context information tracked for each isolate. */
-class _IsolateContext {
-  /** Current isolate id. */
-  int id;
-
-  /** Registry of receive ports currently active on this isolate. */
-  Map<int, ReceivePort> ports;
-
-  /** Holds isolate globals (statics and top-level properties). */
-  var isolateStatics; // native object containing all globals of an isolate.
-
-  _IsolateContext() {
-    id = _globalState.nextIsolateId++;
-    ports = new Map<int, ReceivePort>();
-    initGlobals();
-  }
-
-  // these are filled lazily the first time the isolate starts running.
-  void initGlobals() native @'$initGlobals(this);';
-
-  /**
-   * Run [code] in the context of the isolate represented by [this]. Note this
-   * is called from JavaScript (see $wrap_call in corejs.dart).
-   */
-  Dynamic eval(Function code) {
-    var old = _globalState.currentContext;
-    _globalState.currentContext = this;
-    this._setGlobals();
-    var result = null;
-    try {
-      result = code();
-    } finally {
-      _globalState.currentContext = old;
-      if (old != null) old._setGlobals();
-    }
-    return result;
-  }
-
-  void _setGlobals() native @'$setGlobals(this);';
-
-  /** Lookup a port registered for this isolate. */
-  ReceivePort lookup(int portId) => ports[portId];
-
-  /** Register a port on this isolate. */
-  void register(int portId, ReceivePort port)  {
-    if (ports.containsKey(portId)) {
-      throw new Exception("Registry: ports must be registered only once.");
-    }
-    ports[portId] = port;
-    _globalState.isolates[id] = this; // indicate this isolate is active
-  }
-
-  /** Unregister a port on this isolate. */
-  void unregister(int portId) {
-    ports.remove(portId);
-    if (ports.isEmpty()) {
-      _globalState.isolates.remove(id); // indicate this isolate is not active
-    }
-  }
-}
-
-/** Represent the event loop on a javascript thread (DOM or worker). */
-class _EventLoop {
-  Queue<_IsolateEvent> events;
-
-  _EventLoop() : events = new Queue<_IsolateEvent>();
-
-  void enqueue(isolate, fn, msg) {
-    events.addLast(new _IsolateEvent(isolate, fn, msg));
-  }
-
-  _IsolateEvent dequeue() {
-    if (events.isEmpty()) return null;
-    return events.removeFirst();
-  }
-
-  /** Process a single event, if any. */
-  bool runIteration() {
-    final event = dequeue();
-    if (event == null) {
-      if (_globalState.isWorker) {
-        _globalState.maybeCloseWorker();
-      } else if (_globalState.rootContext != null &&
-                 _globalState.isolates.containsKey(
-                     _globalState.rootContext.id) &&
-                 _globalState.fromCommandLine &&
-                 _globalState.rootContext.ports.isEmpty()) {
-        // We want to reach here only on the main [_Manager] and only
-        // on the command-line.  In the browser the isolate might
-        // still be alive due to DOM callbacks, but the presumption is
-        // that on the command-line, no future events can be injected
-        // into the event queue once it's empty.  Node has setTimeout
-        // so this presumption is incorrect there.  We think(?) that
-        // in d8 this assumption is valid.
-        throw new Exception("Program exited with open ReceivePorts.");
-      }
-      return false;
-    }
-    event.process();
-    return true;
-  }
-
-  /**
-   * Runs multiple iterations of the run-loop. If possible, each iteration is
-   * run asynchronously.
-   */
-  void _runHelper() {
-    // [_window] is defined in timer_provider.dart.
-    if (_window != null) {
-      // Run each iteration from the browser's top event loop.
-      void next() {
-        if (!runIteration()) return;
-        _window.setTimeout(next, 0);
-      }
-      next();
-    } else {
-      // Run synchronously until no more iterations are available.
-      while (runIteration()) {}
-    }
-  }
-
-  /**
-   * Call [_runHelper] but ensure that worker exceptions are propragated. Note
-   * this is called from JavaScript (see $wrap_call in corejs.dart).
-   */
-  void run() {
-    if (!_globalState.isWorker) {
-      _runHelper();
-    } else {
-      try {
-        _runHelper();
-      } catch(var e, var trace) {
-        _globalState.mainManager.postMessage(_serializeMessage(
-            {'command': 'error', 'msg': '$e\n$trace' }));
-      }
-    }
-  }
-}
-
-/** An event in the top-level event queue. */
-class _IsolateEvent {
-  _IsolateContext isolate;
-  Function fn;
-  String message;
-
-  _IsolateEvent(this.isolate, this.fn, this.message);
-
-  void process() {
-    isolate.eval(fn);
-  }
-}
-
-/** An interface for a stub used to interact with a manager. */
-interface _ManagerStub {
-  get id();
-  void set id(int i);
-  void set onmessage(Function f);
-  void postMessage(msg);
-  void terminate();
-}
-
-/** A stub for interacting with the main manager. */
-class _MainManagerStub implements _ManagerStub {
-  get id() => 0;
-  void set id(int i) { throw new NotImplementedException(); }
-  void set onmessage(f) {
-    throw new Exception("onmessage should not be set on MainManagerStub");
-  }
-  void postMessage(msg) native @"$globalThis.postMessage(msg);";
-  void terminate() {}  // Nothing useful to do here.
-}
-
-/**
- * A stub for interacting with a manager built on a web worker. The
- * type Worker is also defined in 'dart:dom_deprecated', but we define
- * it here to avoid introducing a dependency from corelib to dom. This
- * definition uses a 'hidden' type (* prefix on the native name) to
- * enforce that the type is defined dynamically only when web workers
- * are actually available.
- */
-class _WorkerStub implements _ManagerStub native "*Worker" {
-  get id() native "return this.id;";
-  void set id(i) native "this.id = i;";
-  void set onmessage(f) native "this.onmessage = f;";
-  void postMessage(msg) native "return this.postMessage(msg);";
-  // terminate() is implemented by Worker.
-  abstract void terminate();
-}
-
-final String _SPAWNED_SIGNAL = "spawned";
-
-class _IsolateNatives {
-
-  /**
-   * The src url for the script tag that loaded this code. Used to create
-   * JavaScript workers.
-   */
-  static String get _thisScript() native @"return $thisScriptUrl";
-
-  /** Starts a new worker with the given URL. */
-  static _WorkerStub _newWorker(url) native "return new Worker(url);";
-
-  /**
-   * Assume that [e] is a browser message event and extract its message data.
-   * We don't import the dom explicitly so, when workers are disabled, this
-   * library can also run on top of nodejs.
-   */
-  static _getEventData(e) native "return e.data";
-
-  /**
-   * Process messages on a worker, either to control the worker instance or to
-   * pass messages along to the isolate running in the worker.
-   */
-  static void _processWorkerMessage(sender, e) {
-    var msg = _deserializeMessage(_getEventData(e));
-    switch (msg['command']) {
-      case 'start':
-        _globalState.currentManagerId = msg['id'];
-        Function entryPoint = _getJSFunctionFromName(msg['functionName']);
-        var replyTo = _deserializeMessage(msg['replyTo']);
-        _globalState.topEventLoop.enqueue(new _IsolateContext(), function() {
-          _startIsolate(entryPoint, replyTo);
-        }, 'worker-start');
-        _globalState.topEventLoop.run();
-        break;
-      case 'spawn-worker':
-        _spawnWorker(msg['functionName'], msg['uri'], msg['replyPort']);
-        break;
-      case 'message':
-        msg['port'].send(msg['msg'], msg['replyTo']);
-        _globalState.topEventLoop.run();
-        break;
-      case 'close':
-        _log("Closing Worker");
-        _globalState.managers.remove(sender.id);
-        sender.terminate();
-        _globalState.topEventLoop.run();
-        break;
-      case 'log':
-        _log(msg['msg']);
-        break;
-      case 'print':
-        if (_globalState.isWorker) {
-          _globalState.mainManager.postMessage(
-              _serializeMessage({'command': 'print', 'msg': msg}));
-        } else {
-          print(msg['msg']);
-        }
-        break;
-      case 'error':
-        throw msg['msg'];
-    }
-  }
-
-  /** Log a message, forwarding to the main [_Manager] if appropriate. */
-  static _log(msg) {
-    if (_globalState.isWorker) {
-      _globalState.mainManager.postMessage(
-          _serializeMessage({'command': 'log', 'msg': msg }));
-    } else {
-      try {
-        _consoleLog(msg);
-      } catch(var e, var trace) {
-        throw new Exception(trace);
-      }
-    }
-  }
-
-  static void _consoleLog(msg) native "\$globalThis.console.log(msg);";
-
-  /**
-   * Extract the constructor of runnable, so it can be allocated in another
-   * isolate.
-   */
-  static Dynamic _getJSConstructor(Isolate runnable) native """
-    return runnable.constructor;
-  """;
-
-  /** Extract the constructor name of a runnable */
-  // TODO(sigmund): find a browser-generic way to support this.
-  static Dynamic _getJSConstructorName(Isolate runnable) native """
-    return runnable.constructor.name;
-  """;
-
-  /** Find a constructor given its name. */
-  static Dynamic _getJSConstructorFromName(String factoryName) native """
-    return \$globalThis[factoryName];
-  """;
-
-  static Dynamic _getJSFunctionFromName(String functionName) native """
-    return \$globalThis[functionName];
-  """;
-
-  /**
-   * Get a string name for the function, if possible.  The result for
-   * anonymous functions is browser-dependent -- it may be "" or "anonymous"
-   * but you should probably not count on this.
-   */
-  static String _getJSFunctionName(Function f)
-    native @"return f.$name || (void 0);";
-
-  /** Create a new JavaScript object instance given its constructor. */
-  static Dynamic _allocate(var ctor) native "return new ctor();";
-
-  // TODO(sigmund): clean up above, after we make the new API the default:
-
-  static _spawn(String functionName, String uri, bool isLight) {
-    Completer<SendPort> completer = new Completer<SendPort>();
-    ReceivePort port = new ReceivePort();
-    port.receive((msg, SendPort replyPort) {
-      port.close();
-      assert(msg == _SPAWNED_SIGNAL);
-      completer.complete(replyPort);
-    });
-
-    SendPort signalReply = port.toSendPort();
-
-    if (_globalState.useWorkers && !isLight) {
-      _startWorker(functionName, uri, signalReply);
-    } else {
-      _startNonWorker(functionName, uri, signalReply);
-    }
-    return new _BufferingSendPort(
-        _globalState.currentContext.id, completer.future);
-  }
-
-  static SendPort _startWorker(
-      String functionName, String uri, SendPort replyPort) {
-    if (_globalState.isWorker) {
-      _globalState.mainManager.postMessage(_serializeMessage({
-          'command': 'spawn-worker',
-          'functionName': functionName,
-          'uri': uri,
-          'replyPort': replyPort}));
-    } else {
-      _spawnWorker(functionName, uri, replyPort);
-    }
-  }
-
-  static SendPort _startNonWorker(
-      String functionName, String uri, SendPort replyPort) {
-    // TODO(eub): support IE9 using an iframe -- Dart issue 1702.
-    if (uri != null) throw new UnsupportedOperationException(
-            "Currently spawnUri is not supported without web workers.");
-    _globalState.topEventLoop.enqueue(new _IsolateContext(), function() {
-      final func = _getJSFunctionFromName(functionName);
-      _startIsolate(func, replyPort);
-    }, 'nonworker start');
-  }
-
-  static void _startIsolate(Function topLevel, SendPort replyTo) {
-    _fillStatics(_globalState.currentContext);
-    _lazyPort = new ReceivePort();
-    replyTo.send(_SPAWNED_SIGNAL, port.toSendPort());
-    topLevel();
-  }
-
-  /**
-   * Spawns an isolate in a worker. [factoryName] is the Javascript constructor
-   * name for the isolate entry point class.
-   */
-  static void _spawnWorker(functionName, uri, replyPort) {
-    if (functionName == null) functionName = 'main';
-    if (uri == null) uri = _thisScript;
-    if (!(new Uri.fromString(uri).isAbsolute())) {
-      // The constructor of dom workers requires an absolute URL. If we use a
-      // relative path we will get a DOM exception.
-      String prefix = _thisScript.substring(0, _thisScript.lastIndexOf('/'));
-      uri = "$prefix/$uri";
-    }
-    final worker = _newWorker(uri);
-    worker.onmessage = (e) { _processWorkerMessage(worker, e); };
-    var workerId = _globalState.nextManagerId++;
-    // We also store the id on the worker itself so that we can unregister it.
-    worker.id = workerId;
-    _globalState.managers[workerId] = worker;
-    worker.postMessage(_serializeMessage({
-      'command': 'start',
-      'id': workerId,
-      // Note: we serialize replyPort twice because the child worker needs to
-      // first deserialize the worker id, before it can correctly deserialize
-      // the port (port deserialization is sensitive to what is the current
-      // workerId).
-      'replyTo': _serializeMessage(replyPort),
-      'functionName': functionName }));
-  }
-}