| // 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:_js_embedded_names' |
| show |
| CLASS_ID_EXTRACTOR, |
| CLASS_FIELDS_EXTRACTOR, |
| CREATE_NEW_ISOLATE, |
| CURRENT_SCRIPT, |
| INITIALIZE_EMPTY_INSTANCE, |
| INSTANCE_FROM_CLASS_ID, |
| STATIC_FUNCTION_NAME_PROPERTY_NAME; |
| |
| import 'dart:async'; |
| import 'dart:collection' show Queue; |
| import 'dart:isolate'; |
| import 'dart:_native_typed_data' show NativeByteBuffer, NativeTypedData; |
| |
| import 'dart:_js_helper' |
| show |
| Closure, |
| InternalMap, |
| Primitives, |
| convertDartClosureToJS, |
| createDartClosureFromNameOfStaticFunction, |
| isDartObject, |
| random64, |
| requiresPreamble; |
| |
| import 'dart:_foreign_helper' |
| show |
| DART_CLOSURE_TO_JS, |
| JS, |
| JS_CURRENT_ISOLATE_CONTEXT, |
| JS_EMBEDDED_GLOBAL, |
| JS_SET_STATIC_STATE, |
| IsolateContext; |
| |
| import 'dart:_interceptors' |
| show |
| Interceptor, |
| JSArray, |
| JSExtendableArray, |
| JSFixedArray, |
| JSIndexable, |
| JSMutableArray, |
| JSObject; |
| |
| part 'isolate_serialization.dart'; |
| |
| /** |
| * 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); |
| // If we are not already running the event-loop start it now. |
| if (!_currentIsolate()._isExecutingEvent) _globalState.topEventLoop.run(); |
| return result; |
| } |
| |
| /// 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). |
| enterJsAsync() { |
| _globalState.topEventLoop._activeJsAsyncCount++; |
| } |
| |
| /// Marks leaving a javascript async operation. |
| /// |
| /// See [enterJsAsync]. |
| leaveJsAsync() { |
| _globalState.topEventLoop._activeJsAsyncCount--; |
| assert(_globalState.topEventLoop._activeJsAsyncCount >= 0); |
| } |
| |
| /// Returns true if we are currently in a worker context. |
| bool isWorker() => _globalState.isWorker; |
| |
| /** |
| * Called by the compiler to fetch the current isolate context. |
| */ |
| _IsolateContext _currentIsolate() => _globalState.currentContext; |
| |
| /** |
| * Wrapper that takes the dart entry point and runs it within an isolate. The |
| * dart2js compiler will inject a call of the form |
| * [: startRootIsolate(main); :] when it determines that this wrapping |
| * is needed. For single-isolate applications (e.g. hello world), this |
| * call is not emitted. |
| */ |
| void startRootIsolate(entry, args) { |
| if (args == null) args = []; |
| if (args is! List) { |
| throw new ArgumentError("Arguments to main must be a List: $args"); |
| } |
| _globalState = new _Manager(entry); |
| _globalState._initialize(); |
| |
| // Don't start the main loop again, if we are in a worker. |
| if (_globalState.isWorker) return; |
| final rootContext = new _IsolateContext(); |
| _globalState.rootContext = rootContext; |
| _globalState.isolates[rootContext.id] = rootContext; |
| |
| // BUG(5151491): Setting currentContext should not be necessary, but |
| // because closures passed to the DOM as event handlers do not bind their |
| // isolate automatically we try to give them a reasonable context to live in |
| // by having a "default" isolate (the first one created). |
| _globalState.currentContext = rootContext; |
| if (entry is _MainFunctionArgs) { |
| rootContext.eval(() { |
| entry(args); |
| }); |
| } else if (entry is _MainFunctionArgsMessage) { |
| rootContext.eval(() { |
| entry(args, null); |
| }); |
| } else { |
| rootContext.eval(entry); |
| } |
| _globalState.topEventLoop.run(); |
| } |
| |
| /******************************************************** |
| Inserted from lib/isolate/dart2js/isolateimpl.dart |
| ********************************************************/ |
| |
| /** |
| * 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. |
| * TODO(ahe): The _ManagerStub concept is broken. It was an attempt |
| * to create a common interface between the native Worker class and |
| * _MainManagerStub. |
| */ |
| |
| /** |
| * 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 chance to break the isolate abstraction. |
| _Manager get _globalState => JS('_Manager', 'init.globalState'); |
| |
| set _globalState(_Manager val) { |
| JS('void', 'init.globalState = #', val); |
| } |
| |
| /** 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; |
| |
| /** |
| * 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. */ |
| _MainManagerStub mainManager; |
| |
| /// Registry of active Web Workers. Only used in the main [_Manager]. |
| Map<int, dynamic /* Worker */ > managers; |
| |
| /** The entry point given by [startRootIsolate]. */ |
| final Function entry; |
| |
| _Manager(this.entry); |
| |
| _initialize() { |
| _nativeDetectEnvironment(); |
| topEventLoop = new _EventLoop(); |
| isolates = new Map<int, _IsolateContext>(); |
| managers = new Map<int, dynamic>(); |
| if (isWorker) { |
| // "if we are not the main manager ourself" is the intent. |
| mainManager = new _MainManagerStub(); |
| _nativeInitWorkerMessageHandler(); |
| } |
| } |
| |
| void _nativeDetectEnvironment() { |
| bool isWindowDefined = globalWindow != null; |
| bool isWorkerDefined = globalWorker != null; |
| |
| // `isWorker` must be initialized now, since `IsolateNatives.thisScript` |
| // may access it. |
| isWorker = !isWindowDefined && globalPostMessageDefined; |
| supportsWorkers = |
| isWorker || (isWorkerDefined && IsolateNatives.thisScript != null); |
| fromCommandLine = !isWindowDefined && !isWorker; |
| } |
| |
| void _nativeInitWorkerMessageHandler() { |
| var function = JS( |
| '', |
| '(function (f, a) { return function (e) { f(a, e); }})(#, #)', |
| DART_CLOSURE_TO_JS(IsolateNatives._processWorkerMessage), |
| mainManager); |
| JS('void', r'self.onmessage = #', function); |
| // We ensure dartPrint is defined so that the implementation of the Dart |
| // print method knows what to call. |
| JS( |
| '', |
| '''self.dartPrint = self.dartPrint || (function(serialize) { |
| return function (object) { |
| if (self.console && self.console.log) { |
| self.console.log(object) |
| } else { |
| self.postMessage(serialize(object)); |
| } |
| } |
| })(#)''', |
| DART_CLOSURE_TO_JS(_serializePrintMessage)); |
| } |
| |
| static _serializePrintMessage(object) { |
| return _serializeMessage({'command': 'print', 'msg': object}); |
| } |
| |
| /** |
| * Close the worker running this code if all isolates are done and |
| * there are no active async JavaScript tasks still running. |
| */ |
| void maybeCloseWorker() { |
| if (isWorker && isolates.isEmpty && topEventLoop._activeJsAsyncCount == 0) { |
| mainManager.postMessage(_serializeMessage({'command': 'close'})); |
| } |
| } |
| } |
| |
| /** Context information tracked for each isolate. */ |
| class _IsolateContext implements IsolateContext { |
| /** Current isolate id. */ |
| final int id = _globalState.nextIsolateId++; |
| |
| /** Registry of receive ports currently active on this isolate. */ |
| final Map<int, RawReceivePortImpl> ports = new Map<int, RawReceivePortImpl>(); |
| |
| /** 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('', '#()', JS_EMBEDDED_GLOBAL('', CREATE_NEW_ISOLATE)); |
| |
| final RawReceivePortImpl controlPort = new RawReceivePortImpl._controlPort(); |
| |
| final Capability pauseCapability = new Capability(); |
| final Capability terminateCapability = new Capability(); // License to kill. |
| |
| /// Boolean flag set when the initial method of the isolate has been executed. |
| /// |
| /// Used to avoid considering the isolate dead when it has no open |
| /// receive ports and no scheduled timers, because it hasn't had time to |
| /// create them yet. |
| bool initialized = false; |
| |
| // 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 and responses. |
| var doneHandlers; |
| |
| /** |
| * Queue of functions to call when the current event is complete. |
| * |
| * These events are not just put at the front of the event queue, because |
| * they represent control messages, and should be handled even if the |
| * event queue is paused. |
| */ |
| var _scheduledControlEvents; |
| bool _isExecutingEvent = false; |
| |
| /** Whether uncaught errors are considered fatal. */ |
| bool errorsAreFatal = true; |
| |
| // Set of ports that listen to uncaught errors. |
| Set<SendPort> errorPorts = new Set(); |
| |
| _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(SendPort responsePort, Object response) { |
| if (doneHandlers == null) { |
| doneHandlers = []; |
| } |
| for (int i = 0; i < doneHandlers.length; i += 2) { |
| if (responsePort == doneHandlers[i]) { |
| doneHandlers[i + 1] = response; |
| return; |
| } |
| } |
| doneHandlers.add(responsePort); |
| doneHandlers.add(response); |
| } |
| |
| void removeDoneListener(SendPort responsePort) { |
| if (doneHandlers == null) return; |
| for (int i = 0; i < doneHandlers.length; i += 2) { |
| if (responsePort == doneHandlers[i]) { |
| doneHandlers.removeRange(i, i + 2); |
| return; |
| } |
| } |
| } |
| |
| void setErrorsFatal(Capability authentification, bool errorsAreFatal) { |
| if (terminateCapability != authentification) return; |
| this.errorsAreFatal = errorsAreFatal; |
| } |
| |
| void handlePing(SendPort responsePort, int pingType, Object response) { |
| if (pingType == Isolate.IMMEDIATE || |
| (pingType == Isolate.BEFORE_NEXT_EVENT && !_isExecutingEvent)) { |
| responsePort.send(response); |
| return; |
| } |
| void respond() { |
| responsePort.send(response); |
| } |
| |
| assert(pingType == Isolate.BEFORE_NEXT_EVENT); |
| if (_scheduledControlEvents == null) { |
| _scheduledControlEvents = new Queue(); |
| } |
| _scheduledControlEvents.addLast(respond); |
| } |
| |
| void handleKill(Capability authentification, int priority) { |
| if (this.terminateCapability != authentification) return; |
| if (priority == Isolate.IMMEDIATE || |
| (priority == Isolate.BEFORE_NEXT_EVENT && !_isExecutingEvent)) { |
| kill(); |
| return; |
| } |
| assert(priority == Isolate.BEFORE_NEXT_EVENT); |
| if (_scheduledControlEvents == null) { |
| _scheduledControlEvents = new Queue(); |
| } |
| _scheduledControlEvents.addLast(kill); |
| } |
| |
| void addErrorListener(SendPort port) { |
| errorPorts.add(port); |
| } |
| |
| void removeErrorListener(SendPort port) { |
| errorPorts.remove(port); |
| } |
| |
| /** Function called with an uncaught error. */ |
| void handleUncaughtError(error, StackTrace stackTrace) { |
| // Just print the error if there is no error listener registered. |
| if (errorPorts.isEmpty) { |
| // An uncaught error in the root isolate will terminate the program? |
| if (errorsAreFatal && identical(this, _globalState.rootContext)) { |
| // The error will be rethrown to reach the global scope, so |
| // don't print it. |
| return; |
| } |
| if (JS('bool', 'self.console && self.console.error')) { |
| JS('void', 'self.console.error(#, #)', error, stackTrace); |
| } else { |
| print(error); |
| if (stackTrace != null) print(stackTrace); |
| } |
| return; |
| } |
| List message = new List(2) |
| ..[0] = error.toString() |
| ..[1] = (stackTrace == null) ? null : stackTrace.toString(); |
| for (SendPort port in errorPorts) port.send(message); |
| } |
| |
| /** |
| * 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; |
| var oldIsExecutingEvent = _isExecutingEvent; |
| _isExecutingEvent = true; |
| try { |
| result = code(); |
| } catch (e, s) { |
| handleUncaughtError(e, s); |
| if (errorsAreFatal) { |
| kill(); |
| // An uncaught error in the root context terminates all isolates. |
| if (identical(this, _globalState.rootContext)) { |
| rethrow; |
| } |
| } |
| } finally { |
| _isExecutingEvent = oldIsExecutingEvent; |
| _globalState.currentContext = old; |
| if (old != null) old._setGlobals(); |
| if (_scheduledControlEvents != null) { |
| while (_scheduledControlEvents.isNotEmpty) { |
| (_scheduledControlEvents.removeFirst())(); |
| } |
| } |
| } |
| return result; |
| } |
| |
| void _setGlobals() { |
| JS_SET_STATIC_STATE(isolateStatics); |
| } |
| |
| /** |
| * Handle messages coming in on the control port. |
| * |
| * These events do not go through the event queue. |
| * The `_globalState.currentContext` context is not set to this context |
| * during the handling. |
| */ |
| void handleControlMessage(message) { |
| switch (message[0]) { |
| case 'pause': |
| addPause(message[1], message[2]); |
| break; |
| case 'resume': |
| removePause(message[1]); |
| break; |
| case 'add-ondone': |
| addDoneListener(message[1], message[2]); |
| break; |
| case 'remove-ondone': |
| removeDoneListener(message[1]); |
| break; |
| case 'set-errors-fatal': |
| setErrorsFatal(message[1], message[2]); |
| break; |
| case 'ping': |
| handlePing(message[1], message[2], message[3]); |
| break; |
| case 'kill': |
| handleKill(message[1], message[2]); |
| break; |
| case 'getErrors': |
| addErrorListener(message[1]); |
| break; |
| case 'stopErrors': |
| removeErrorListener(message[1]); |
| break; |
| default: |
| } |
| } |
| |
| /** 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); |
| } |
| |
| void _updateGlobalState() { |
| if (ports.length - weakPorts.length > 0 || isPaused || !initialized) { |
| _globalState.isolates[id] = this; // indicate this isolate is active |
| } else { |
| kill(); |
| } |
| } |
| |
| void kill() { |
| if (_scheduledControlEvents != null) { |
| // Kill all pending events. |
| _scheduledControlEvents.clear(); |
| } |
| // Stop listening on all ports. |
| // This should happen before sending events to done handlers, in case |
| // we are listening on ourselves. |
| // Closes all ports, including control port. |
| for (var port in ports.values) { |
| port._close(); |
| } |
| ports.clear(); |
| weakPorts.clear(); |
| _globalState.isolates.remove(id); // indicate this isolate is not active |
| errorPorts.clear(); |
| if (doneHandlers != null) { |
| for (int i = 0; i < doneHandlers.length; i += 2) { |
| SendPort responsePort = doneHandlers[i]; |
| Object response = doneHandlers[i + 1]; |
| responsePort.send(response); |
| } |
| doneHandlers = 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 { |
| final Queue<_IsolateEvent> events = new Queue<_IsolateEvent>(); |
| |
| /// The number of waiting callbacks not controlled by the dart event loop. |
| /// |
| /// This could be timers or http requests. The worker will only be killed if |
| /// this count reaches 0. |
| /// Access this by using [enterJsAsync] before starting a JavaScript async |
| /// operation and [leaveJsAsync] when the callback has fired. |
| int _activeJsAsyncCount = 0; |
| |
| _EventLoop(); |
| |
| void enqueue(isolate, fn, msg) { |
| events.addLast(new _IsolateEvent(isolate, fn, msg)); |
| } |
| |
| void prequeue(_IsolateEvent event) { |
| events.addFirst(event); |
| } |
| |
| _IsolateEvent dequeue() { |
| if (events.isEmpty) return null; |
| return events.removeFirst(); |
| } |
| |
| void checkOpenReceivePortsFromCommandLine() { |
| 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.'); |
| } |
| } |
| |
| /** Process a single event, if any. */ |
| bool runIteration() { |
| final event = dequeue(); |
| if (event == null) { |
| checkOpenReceivePortsFromCommandLine(); |
| _globalState.maybeCloseWorker(); |
| return false; |
| } |
| event.process(); |
| return true; |
| } |
| |
| /** |
| * Runs multiple iterations of the run-loop. If possible, each iteration is |
| * run asynchronously. |
| */ |
| void _runHelper() { |
| if (globalWindow != null) { |
| // Run each iteration from the browser's top event loop. |
| void next() { |
| if (!runIteration()) return; |
| Timer.run(next); |
| } |
| |
| next(); |
| } else { |
| // Run synchronously until no more iterations are available. |
| while (runIteration()) {} |
| } |
| } |
| |
| /** |
| * Call [_runHelper] but ensure that worker exceptions are propagated. |
| */ |
| void run() { |
| if (!_globalState.isWorker) { |
| _runHelper(); |
| } else { |
| try { |
| _runHelper(); |
| } catch (e, 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() { |
| if (isolate.isPaused) { |
| isolate.delayedEvents.add(this); |
| return; |
| } |
| isolate.eval(fn); |
| } |
| } |
| |
| /** A stub for interacting with the main manager. */ |
| class _MainManagerStub { |
| void postMessage(msg) { |
| // "self" is a way to refer to the global context object that |
| // works in HTML pages and in Web Workers. It does not work in d8 |
| // and Firefox jsshell, because that would have been too easy. |
| // |
| // See: http://www.w3.org/TR/workers/#the-global-scope |
| // and: http://www.w3.org/TR/Window/#dfn-self-attribute |
| requiresPreamble(); |
| JS('void', r'self.postMessage(#)', msg); |
| } |
| } |
| |
| const String _SPAWNED_SIGNAL = 'spawned'; |
| const String _SPAWN_FAILED_SIGNAL = 'spawn failed'; |
| |
| get globalWindow { |
| requiresPreamble(); |
| return JS('', 'self.window'); |
| } |
| |
| get globalWorker { |
| requiresPreamble(); |
| return JS('', 'self.Worker'); |
| } |
| |
| bool get globalPostMessageDefined { |
| requiresPreamble(); |
| return JS('bool', '!!self.postMessage'); |
| } |
| |
| typedef _MainFunction(); |
| typedef _MainFunctionArgs(args); |
| typedef _MainFunctionArgsMessage(args, message); |
| |
| /// Note: IsolateNatives depends on _globalState which is only set up correctly |
| /// when 'dart:isolate' has been imported. |
| class IsolateNatives { |
| // We set [enableSpawnWorker] to true (not null) when calling isolate |
| // primitives that require support for spawning workers. The field starts out |
| // by being null, and dart2js' type inference will track if it can have a |
| // non-null value. So by testing if this value is not null, we generate code |
| // that dart2js knows is dead when worker support isn't needed. |
| // TODO(herhut): Initialize this to false when able to track compile-time |
| // constants. |
| static var enableSpawnWorker; |
| |
| static String thisScript = computeThisScript(); |
| |
| /// Returns the base path added to Uri.base to resolve `package:` Uris. |
| /// |
| /// This is used by `Isolate.resolvePackageUri` to load resources. The default |
| /// value is `packages/` but users can override this by using the |
| /// `defaultPackagesBase` hook. |
| static String get packagesBase => |
| JS('String', r'self.defaultPackagesBase || "packages/"'); |
| |
| /// 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 function. |
| * |
| * Used to create JavaScript workers and load deferred libraries. |
| */ |
| static String computeThisScript() { |
| var currentScript = JS_EMBEDDED_GLOBAL('', CURRENT_SCRIPT); |
| if (currentScript != null) { |
| return JS('String', 'String(#.src)', currentScript); |
| } |
| // A worker has no script tag - so get an url from a stack-trace. |
| if (_globalState.isWorker) return computeThisScriptFromTrace(); |
| // An isolate that doesn't support workers, but doesn't have a |
| // currentScript either. This is most likely a Chrome extension. |
| return null; |
| } |
| |
| static String computeThisScriptFromTrace() { |
| var stack = JS('String|Null', 'new Error().stack'); |
| if (stack == null) { |
| // According to Internet Explorer documentation, the stack |
| // property is not set until the exception is thrown. The stack |
| // property was not provided until IE10. |
| stack = JS( |
| 'String|Null', |
| '(function() {' |
| 'try { throw new Error() } catch(e) { return e.stack }' |
| '})()'); |
| if (stack == null) throw new UnsupportedError('No stack trace'); |
| } |
| var pattern, matches; |
| |
| // This pattern matches V8, Chrome, and Internet Explorer stack |
| // traces that look like this: |
| // Error |
| // at methodName (URI:LINE:COLUMN) |
| pattern = |
| JS('', r'new RegExp("^ *at [^(]*\\((.*):[0-9]*:[0-9]*\\)$", "m")'); |
| |
| matches = JS('JSExtendableArray|Null', '#.match(#)', stack, pattern); |
| if (matches != null) return JS('String', '#[1]', matches); |
| |
| // This pattern matches Firefox stack traces that look like this: |
| // methodName@URI:LINE |
| pattern = JS('', r'new RegExp("^[^@]*@(.*):[0-9]*$", "m")'); |
| |
| matches = JS('JSExtendableArray|Null', '#.match(#)', stack, pattern); |
| if (matches != null) return JS('String', '#[1]', matches); |
| |
| throw new UnsupportedError('Cannot extract URI from "$stack"'); |
| } |
| |
| /** |
| * 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) => JS('', '#.data', e); |
| |
| /** |
| * 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(/* Worker */ sender, e) { |
| var msg = _deserializeMessage(_getEventData(e)); |
| switch (msg['command']) { |
| case 'start': |
| _globalState.currentManagerId = msg['id']; |
| String functionName = msg['functionName']; |
| Function entryPoint = (functionName == null) |
| ? _globalState.entry |
| : _getJSFunctionFromName(functionName); |
| var args = msg['args']; |
| var message = _deserializeMessage(msg['msg']); |
| var isSpawnUri = msg['isSpawnUri']; |
| var startPaused = msg['startPaused']; |
| var replyTo = _deserializeMessage(msg['replyTo']); |
| var context = new _IsolateContext(); |
| _globalState.topEventLoop.enqueue(context, () { |
| _startIsolate( |
| entryPoint, args, message, isSpawnUri, startPaused, replyTo); |
| }, 'worker-start'); |
| // Make sure we always have a current context in this worker. |
| // TODO(7907): This is currently needed because we're using |
| // Timers to implement Futures, and this isolate library |
| // implementation uses Futures. We should either stop using |
| // Futures in this library, or re-adapt if Futures get a |
| // different implementation. |
| _globalState.currentContext = context; |
| _globalState.topEventLoop.run(); |
| break; |
| case 'spawn-worker': |
| if (enableSpawnWorker != null) handleSpawnWorkerRequest(msg); |
| break; |
| case 'message': |
| SendPort port = msg['port']; |
| // If the port has been closed, we ignore the message. |
| if (port != null) { |
| msg['port'].send(msg['msg']); |
| } |
| _globalState.topEventLoop.run(); |
| break; |
| case 'close': |
| _globalState.managers.remove(workerIds[sender]); |
| JS('void', '#.terminate()', sender); |
| _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']; |
| } |
| } |
| |
| static handleSpawnWorkerRequest(msg) { |
| var replyPort = msg['replyPort']; |
| spawn(msg['functionName'], msg['uri'], msg['args'], msg['msg'], false, |
| msg['isSpawnUri'], msg['startPaused']).then((msg) { |
| replyPort.send(msg); |
| }, onError: (String errorMessage) { |
| replyPort.send([_SPAWN_FAILED_SIGNAL, errorMessage]); |
| }); |
| } |
| |
| /** 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 (e, trace) { |
| throw new Exception(trace); |
| } |
| } |
| } |
| |
| static void _consoleLog(msg) { |
| requiresPreamble(); |
| JS('void', r'self.console.log(#)', msg); |
| } |
| |
| static _getJSFunctionFromName(String functionName) { |
| return createDartClosureFromNameOfStaticFunction(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) { |
| return (f is Closure) |
| ? JS('String|Null', r'#[#]', f, STATIC_FUNCTION_NAME_PROPERTY_NAME) |
| : null; |
| } |
| |
| /** Create a new JavaScript object instance given its constructor. */ |
| static dynamic _allocate(var ctor) { |
| return JS('', 'new #()', ctor); |
| } |
| |
| static Future<List> spawnFunction( |
| void topLevelFunction(message), var message, bool startPaused) { |
| IsolateNatives.enableSpawnWorker = true; |
| final name = _getJSFunctionName(topLevelFunction); |
| if (name == null) { |
| throw new UnsupportedError('only top-level functions can be spawned.'); |
| } |
| bool isLight = false; |
| bool isSpawnUri = false; |
| return spawn(name, null, null, message, isLight, isSpawnUri, startPaused); |
| } |
| |
| static Future<List> spawnUri( |
| Uri uri, List<String> args, var message, bool startPaused) { |
| IsolateNatives.enableSpawnWorker = true; |
| bool isLight = false; |
| bool isSpawnUri = true; |
| return spawn( |
| null, uri.toString(), args, message, isLight, isSpawnUri, startPaused); |
| } |
| |
| // TODO(sigmund): clean up above, after we make the new API the default: |
| |
| /// If [uri] is `null` it is replaced with the current script. |
| static Future<List> spawn(String functionName, String uri, List<String> args, |
| message, bool isLight, bool isSpawnUri, bool startPaused) { |
| // Assume that the compiled version of the Dart file lives just next to the |
| // dart file. |
| // TODO(floitsch): support precompiled version of dart2js output. |
| if (uri != null && uri.endsWith('.dart')) uri += '.js'; |
| |
| ReceivePort port = new ReceivePort(); |
| Completer<List> completer = new Completer(); |
| port.first.then((msg) { |
| if (msg[0] == _SPAWNED_SIGNAL) { |
| completer.complete(msg); |
| } else { |
| assert(msg[0] == _SPAWN_FAILED_SIGNAL); |
| completer.completeError(msg[1]); |
| } |
| }); |
| |
| SendPort signalReply = port.sendPort; |
| |
| if (_globalState.useWorkers && !isLight) { |
| _startWorker(functionName, uri, args, message, isSpawnUri, startPaused, |
| signalReply, (String message) => completer.completeError(message)); |
| } else { |
| _startNonWorker(functionName, uri, args, message, isSpawnUri, startPaused, |
| signalReply); |
| } |
| return completer.future; |
| } |
| |
| static void _startWorker( |
| String functionName, |
| String uri, |
| List<String> args, |
| message, |
| bool isSpawnUri, |
| bool startPaused, |
| SendPort replyPort, |
| void onError(String message)) { |
| // Make sure that the args list is a fresh generic list. A newly spawned |
| // isolate should be able to assume that the arguments list is an |
| // extendable list. |
| if (args != null) args = new List<String>.from(args); |
| if (_globalState.isWorker) { |
| _globalState.mainManager.postMessage(_serializeMessage({ |
| 'command': 'spawn-worker', |
| 'functionName': functionName, |
| 'args': args, |
| 'msg': message, |
| 'uri': uri, |
| 'isSpawnUri': isSpawnUri, |
| 'startPaused': startPaused, |
| 'replyPort': replyPort |
| })); |
| } else { |
| _spawnWorker(functionName, uri, args, message, isSpawnUri, startPaused, |
| replyPort, onError); |
| } |
| } |
| |
| static void _startNonWorker( |
| String functionName, |
| String uri, |
| List<String> args, |
| var message, |
| bool isSpawnUri, |
| bool startPaused, |
| SendPort replyPort) { |
| // TODO(eub): support IE9 using an iframe -- Dart issue 1702. |
| if (uri != null) { |
| throw new UnsupportedError( |
| 'Currently spawnUri is not supported without web workers.'); |
| } |
| // Clone the message to enforce the restrictions we have on isolate |
| // messages. |
| message = _clone(message); |
| // Make sure that the args list is a fresh generic list. A newly spawned |
| // isolate should be able to assume that the arguments list is an |
| // extendable list. |
| if (args != null) args = new List<String>.from(args); |
| _globalState.topEventLoop.enqueue(new _IsolateContext(), () { |
| final func = _getJSFunctionFromName(functionName); |
| _startIsolate(func, args, message, isSpawnUri, startPaused, replyPort); |
| }, 'nonworker start'); |
| } |
| |
| static Isolate get currentIsolate { |
| _IsolateContext context = JS_CURRENT_ISOLATE_CONTEXT(); |
| return new Isolate(context.controlPort.sendPort, |
| pauseCapability: context.pauseCapability, |
| terminateCapability: context.terminateCapability); |
| } |
| |
| 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.terminateCapability |
| ]); |
| |
| void runStartFunction() { |
| context.initialized = true; |
| if (!isSpawnUri) { |
| topLevel(message); |
| } else if (topLevel is _MainFunctionArgsMessage) { |
| topLevel(args, message); |
| } else if (topLevel is _MainFunctionArgs) { |
| topLevel(args); |
| } else { |
| topLevel(); |
| } |
| context._updateGlobalState(); |
| } |
| |
| if (startPaused) { |
| context.addPause(context.pauseCapability, context.pauseCapability); |
| _globalState.topEventLoop |
| .enqueue(context, runStartFunction, 'start isolate'); |
| } else { |
| runStartFunction(); |
| } |
| } |
| |
| /** |
| * Spawns an isolate in a worker. [factoryName] is the Javascript constructor |
| * name for the isolate entry point class. |
| */ |
| static void _spawnWorker( |
| functionName, |
| String uri, |
| List<String> args, |
| message, |
| bool isSpawnUri, |
| bool startPaused, |
| SendPort replyPort, |
| void onError(String message)) { |
| if (uri == null) uri = thisScript; |
| final worker = JS('var', 'new Worker(#)', uri); |
| // Trampolines are used when wanting to call a Dart closure from |
| // JavaScript. The helper function DART_CLOSURE_TO_JS only accepts |
| // top-level or static methods, and the trampoline allows us to capture |
| // arguments and values which can be passed to a static method. |
| final onerrorTrampoline = JS( |
| '', |
| ''' |
| (function (f, u, c) { |
| return function(e) { |
| return f(e, u, c) |
| } |
| })(#, #, #)''', |
| DART_CLOSURE_TO_JS(workerOnError), |
| uri, |
| onError); |
| JS('void', '#.onerror = #', worker, onerrorTrampoline); |
| |
| var processWorkerMessageTrampoline = JS( |
| '', |
| """ |
| (function (f, a) { |
| return function (e) { |
| // We can stop listening for errors when the first message is received as |
| // we only listen for messages to determine if the uri was bad. |
| e.onerror = null; |
| return f(a, e); |
| } |
| })(#, #)""", |
| DART_CLOSURE_TO_JS(_processWorkerMessage), |
| worker); |
| JS('void', '#.onmessage = #', worker, processWorkerMessageTrampoline); |
| var workerId = _globalState.nextManagerId++; |
| // We also store the id on the worker itself so that we can unregister it. |
| workerIds[worker] = workerId; |
| _globalState.managers[workerId] = worker; |
| JS( |
| 'void', |
| '#.postMessage(#)', |
| worker, |
| _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), |
| 'args': args, |
| 'msg': _serializeMessage(message), |
| 'isSpawnUri': isSpawnUri, |
| 'startPaused': startPaused, |
| 'functionName': functionName |
| })); |
| } |
| |
| static bool workerOnError( |
| /* Event */ event, |
| String uri, |
| void onError(String message)) { |
| // Attempt to shut up the browser, as the error has been handled. Chrome |
| // ignores this :-( |
| JS('void', '#.preventDefault()', event); |
| String message = JS('String|Null', '#.message', event); |
| if (message == null) { |
| // Some browsers, including Chrome, fail to provide a proper error |
| // event. |
| message = 'Error spawning worker for $uri'; |
| } else { |
| message = 'Error spawning worker for $uri ($message)'; |
| } |
| onError(message); |
| return true; |
| } |
| } |
| |
| /******************************************************** |
| Inserted from lib/isolate/dart2js/ports.dart |
| ********************************************************/ |
| |
| /** Common functionality to all send ports. */ |
| abstract class _BaseSendPort implements SendPort { |
| /** Id for the destination isolate. */ |
| final int _isolateId; |
| |
| const _BaseSendPort(this._isolateId); |
| |
| void _checkReplyTo(SendPort replyTo) { |
| if (replyTo != null && |
| replyTo is! _NativeJsSendPort && |
| replyTo is! _WorkerSendPort) { |
| throw new Exception('SendPort.send: Illegal replyTo port type'); |
| } |
| } |
| |
| void send(var message); |
| bool operator ==(var other); |
| int get hashCode; |
| } |
| |
| /** A send port that delivers messages in-memory via native JavaScript calls. */ |
| class _NativeJsSendPort extends _BaseSendPort implements SendPort { |
| final RawReceivePortImpl _receivePort; |
| |
| const _NativeJsSendPort(this._receivePort, int isolateId) : super(isolateId); |
| |
| void send(var message) { |
| // Check that the isolate still runs and the port is still open |
| final isolate = _globalState.isolates[_isolateId]; |
| if (isolate == null) return; |
| if (_receivePort._isClosed) return; |
| // Clone the message to enforce the restrictions we have on isolate |
| // messages. |
| var msg = _clone(message); |
| if (isolate.controlPort == _receivePort) { |
| isolate.handleControlMessage(msg); |
| return; |
| } |
| _globalState.topEventLoop.enqueue(isolate, () { |
| if (!_receivePort._isClosed) { |
| _receivePort._add(msg); |
| } |
| }, 'receive'); |
| } |
| |
| bool operator ==(var other) => |
| (other is _NativeJsSendPort) && (_receivePort == other._receivePort); |
| |
| int get hashCode => _receivePort._id; |
| } |
| |
| /** A send port that delivers messages via worker.postMessage. */ |
| // TODO(eub): abstract this for iframes. |
| class _WorkerSendPort extends _BaseSendPort implements SendPort { |
| final int _workerId; |
| final int _receivePortId; |
| |
| const _WorkerSendPort(this._workerId, int isolateId, this._receivePortId) |
| : super(isolateId); |
| |
| void send(var message) { |
| final workerMessage = |
| _serializeMessage({'command': 'message', 'port': this, 'msg': message}); |
| |
| if (_globalState.isWorker) { |
| // Communication from one worker to another go through the |
| // main worker. |
| _globalState.mainManager.postMessage(workerMessage); |
| } else { |
| // Deliver the message only if the worker is still alive. |
| /* Worker */ var manager = _globalState.managers[_workerId]; |
| if (manager != null) { |
| JS('void', '#.postMessage(#)', manager, workerMessage); |
| } |
| } |
| } |
| |
| bool operator ==(var other) { |
| return (other is _WorkerSendPort) && |
| (_workerId == other._workerId) && |
| (_isolateId == other._isolateId) && |
| (_receivePortId == other._receivePortId); |
| } |
| |
| int get hashCode { |
| // TODO(sigmund): use a standard hash when we get one available in corelib. |
| return (_workerId << 16) ^ (_isolateId << 8) ^ _receivePortId; |
| } |
| } |
| |
| class RawReceivePortImpl implements RawReceivePort { |
| static int _nextFreeId = 1; |
| |
| final int _id; |
| Function _handler; |
| bool _isClosed = false; |
| |
| RawReceivePortImpl(this._handler) : _id = _nextFreeId++ { |
| _globalState.currentContext.register(_id, this); |
| } |
| |
| RawReceivePortImpl.weak(this._handler) : _id = _nextFreeId++ { |
| _globalState.currentContext.registerWeak(_id, this); |
| } |
| |
| // Creates the control port of an isolate. |
| // This is created before the isolate context object itself, |
| // so it cannot access the static _nextFreeId field. |
| RawReceivePortImpl._controlPort() |
| : _handler = null, |
| _id = 0; |
| |
| void set handler(Function newHandler) { |
| _handler = newHandler; |
| } |
| |
| // Close the port without unregistering it. |
| // Used by an isolate context to close all ports when shutting down. |
| void _close() { |
| _isClosed = true; |
| _handler = null; |
| } |
| |
| void close() { |
| if (_isClosed) return; |
| _isClosed = true; |
| _handler = null; |
| _globalState.currentContext.unregister(_id); |
| } |
| |
| void _add(dataEvent) { |
| if (_isClosed) return; |
| _handler(dataEvent); |
| } |
| |
| SendPort get sendPort { |
| return new _NativeJsSendPort(this, _globalState.currentContext.id); |
| } |
| } |
| |
| class ReceivePortImpl extends Stream implements ReceivePort { |
| final RawReceivePort _rawPort; |
| StreamController _controller; |
| |
| ReceivePortImpl() : this.fromRawReceivePort(new RawReceivePortImpl(null)); |
| |
| ReceivePortImpl.weak() |
| : this.fromRawReceivePort(new RawReceivePortImpl.weak(null)); |
| |
| ReceivePortImpl.fromRawReceivePort(this._rawPort) { |
| _controller = new StreamController(onCancel: close, sync: true); |
| _rawPort.handler = _controller.add; |
| } |
| |
| StreamSubscription listen(void onData(var event), |
| {Function onError, void onDone(), bool cancelOnError}) { |
| return _controller.stream.listen(onData, |
| onError: onError, onDone: onDone, cancelOnError: cancelOnError); |
| } |
| |
| void close() { |
| _rawPort.close(); |
| _controller.close(); |
| } |
| |
| SendPort get sendPort => _rawPort.sendPort; |
| } |
| |
| class TimerImpl implements Timer { |
| final bool _once; |
| bool _inEventLoop = false; |
| int _handle; |
| |
| TimerImpl(int milliseconds, void callback()) : _once = true { |
| if (milliseconds == 0 && (!hasTimer() || _globalState.isWorker)) { |
| void internalCallback() { |
| _handle = null; |
| callback(); |
| } |
| |
| // Setting _handle to something different from null indicates that the |
| // callback has not been run. Hence, the choice of 1 is arbitrary. |
| _handle = 1; |
| |
| // This makes a dependency between the async library and the |
| // event loop of the isolate library. The compiler makes sure |
| // that the event loop is compiled if [Timer] is used. |
| // TODO(7907): In case of web workers, we need to use the event |
| // loop instead of setTimeout, to make sure the futures get executed in |
| // order. |
| _globalState.topEventLoop |
| .enqueue(_globalState.currentContext, internalCallback, 'timer'); |
| _inEventLoop = true; |
| } else if (hasTimer()) { |
| void internalCallback() { |
| _handle = null; |
| leaveJsAsync(); |
| callback(); |
| } |
| |
| enterJsAsync(); |
| |
| _handle = JS('int', 'self.setTimeout(#, #)', |
| convertDartClosureToJS(internalCallback, 0), milliseconds); |
| } else { |
| assert(milliseconds > 0); |
| throw new UnsupportedError('Timer greater than 0.'); |
| } |
| } |
| |
| TimerImpl.periodic(int milliseconds, void callback(Timer timer)) |
| : _once = false { |
| if (hasTimer()) { |
| enterJsAsync(); |
| _handle = JS( |
| 'int', |
| 'self.setInterval(#, #)', |
| convertDartClosureToJS(() { |
| callback(this); |
| }, 0), |
| milliseconds); |
| } else { |
| throw new UnsupportedError('Periodic timer.'); |
| } |
| } |
| |
| void cancel() { |
| if (hasTimer()) { |
| if (_inEventLoop) { |
| throw new UnsupportedError('Timer in event loop cannot be canceled.'); |
| } |
| if (_handle == null) return; |
| leaveJsAsync(); |
| if (_once) { |
| JS('void', 'self.clearTimeout(#)', _handle); |
| } else { |
| JS('void', 'self.clearInterval(#)', _handle); |
| } |
| _handle = null; |
| } else { |
| throw new UnsupportedError('Canceling a timer.'); |
| } |
| } |
| |
| bool get isActive => _handle != null; |
| } |
| |
| bool hasTimer() { |
| requiresPreamble(); |
| return JS('', 'self.setTimeout') != null; |
| } |
| |
| /** |
| * Implementation class for [Capability]. |
| * |
| * It has the same name to make it harder for users to distinguish. |
| */ |
| class CapabilityImpl implements Capability { |
| /** Internal random secret identifying the capability. */ |
| final int _id; |
| |
| CapabilityImpl() : this._internal(random64()); |
| |
| CapabilityImpl._internal(this._id); |
| |
| int get hashCode { |
| // Thomas Wang 32 bit Mix. |
| // http://www.concentric.net/~Ttwang/tech/inthash.htm |
| // (via https://gist.github.com/badboy/6267743) |
| int hash = _id; |
| hash = (hash >> 0) ^ (hash ~/ 0x100000000); // To 32 bit from ~64. |
| hash = (~hash + (hash << 15)) & 0xFFFFFFFF; |
| hash ^= hash >> 12; |
| hash = (hash * 5) & 0xFFFFFFFF; |
| hash ^= hash >> 4; |
| hash = (hash * 2057) & 0xFFFFFFFF; |
| hash ^= hash >> 16; |
| return hash; |
| } |
| |
| bool operator ==(Object other) { |
| if (identical(other, this)) return true; |
| if (other is CapabilityImpl) { |
| return identical(_id, other._id); |
| } |
| return false; |
| } |
| } |