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1 // Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file | |
2 // for details. All rights reserved. Use of this source code is governed by a | |
3 // BSD-style license that can be found in the LICENSE file. | |
4 | |
5 library _isolate_helper; | |
6 | |
7 import 'dart:_js_embedded_names' show | |
8 CLASS_ID_EXTRACTOR, | |
9 CLASS_FIELDS_EXTRACTOR, | |
10 CREATE_NEW_ISOLATE, | |
11 CURRENT_SCRIPT, | |
12 GLOBAL_FUNCTIONS, | |
13 INITIALIZE_EMPTY_INSTANCE, | |
14 INSTANCE_FROM_CLASS_ID; | |
15 | |
16 import 'dart:async'; | |
17 import 'dart:collection' show Queue; | |
18 import 'dart:isolate'; | |
19 import 'dart:_native_typed_data' show NativeByteBuffer, NativeTypedData; | |
20 | |
21 import 'dart:_js_helper' show | |
22 Closure, | |
23 InternalMap, | |
24 Null, | |
25 Primitives, | |
26 convertDartClosureToJS, | |
27 isDartObject, | |
28 random64, | |
29 requiresPreamble; | |
30 | |
31 import 'dart:_foreign_helper' show DART_CLOSURE_TO_JS, | |
32 JS, | |
33 JS_CURRENT_ISOLATE_CONTEXT, | |
34 JS_CURRENT_ISOLATE, | |
35 JS_EMBEDDED_GLOBAL, | |
36 JS_SET_CURRENT_ISOLATE, | |
37 IsolateContext; | |
38 | |
39 import 'dart:_interceptors' show Interceptor, | |
40 JSArray, | |
41 JSExtendableArray, | |
42 JSFixedArray, | |
43 JSIndexable, | |
44 JSMutableArray, | |
45 JSObject; | |
46 | |
47 | |
48 part 'isolate_serialization.dart'; | |
49 | |
50 /** | |
51 * Called by the compiler to support switching | |
52 * between isolates when we get a callback from the DOM. | |
53 */ | |
54 _callInIsolate(_IsolateContext isolate, Function function) { | |
55 var result = isolate.eval(function); | |
56 // If we are not already running the event-loop start it now. | |
57 if (!_currentIsolate()._isExecutingEvent) _globalState.topEventLoop.run(); | |
58 return result; | |
59 } | |
60 | |
61 /// Marks entering a JavaScript async operation to keep the worker alive. | |
62 /// | |
63 /// To be called by library code before starting an async operation controlled | |
64 /// by the JavaScript event handler. | |
65 /// | |
66 /// Also call [leaveJsAsync] in all callback handlers marking the end of that | |
67 /// async operation (also error handlers) so the worker can be released. | |
68 /// | |
69 /// These functions only has to be called for code that can be run from a | |
70 /// worker-isolate (so not for general dom operations). | |
71 enterJsAsync() { | |
72 _globalState.topEventLoop._activeJsAsyncCount++; | |
73 } | |
74 | |
75 /// Marks leaving a javascript async operation. | |
76 /// | |
77 /// See [enterJsAsync]. | |
78 leaveJsAsync() { | |
79 _globalState.topEventLoop._activeJsAsyncCount--; | |
80 assert(_globalState.topEventLoop._activeJsAsyncCount >= 0); | |
81 } | |
82 | |
83 /// Returns true if we are currently in a worker context. | |
84 bool isWorker() => _globalState.isWorker; | |
85 | |
86 /** | |
87 * Called by the compiler to fetch the current isolate context. | |
88 */ | |
89 _IsolateContext _currentIsolate() => _globalState.currentContext; | |
90 | |
91 /** | |
92 * Wrapper that takes the dart entry point and runs it within an isolate. The | |
93 * dart2js compiler will inject a call of the form | |
94 * [: startRootIsolate(main); :] when it determines that this wrapping | |
95 * is needed. For single-isolate applications (e.g. hello world), this | |
96 * call is not emitted. | |
97 */ | |
98 void startRootIsolate(entry, args) { | |
99 // The dartMainRunner can inject a new arguments array. We pass the arguments | |
100 // through a "JS", so that the type-inferrer loses track of it. | |
101 args = JS("", "#", args); | |
102 if (args == null) args = []; | |
103 if (args is! List) { | |
104 throw new ArgumentError("Arguments to main must be a List: $args"); | |
105 } | |
106 _globalState = new _Manager(entry); | |
107 | |
108 // Don't start the main loop again, if we are in a worker. | |
109 if (_globalState.isWorker) return; | |
110 final rootContext = new _IsolateContext(); | |
111 _globalState.rootContext = rootContext; | |
112 | |
113 // BUG(5151491): Setting currentContext should not be necessary, but | |
114 // because closures passed to the DOM as event handlers do not bind their | |
115 // isolate automatically we try to give them a reasonable context to live in | |
116 // by having a "default" isolate (the first one created). | |
117 _globalState.currentContext = rootContext; | |
118 if (entry is _MainFunctionArgs) { | |
119 rootContext.eval(() { entry(args); }); | |
120 } else if (entry is _MainFunctionArgsMessage) { | |
121 rootContext.eval(() { entry(args, null); }); | |
122 } else { | |
123 rootContext.eval(entry); | |
124 } | |
125 _globalState.topEventLoop.run(); | |
126 } | |
127 | |
128 /******************************************************** | |
129 Inserted from lib/isolate/dart2js/isolateimpl.dart | |
130 ********************************************************/ | |
131 | |
132 /** | |
133 * Concepts used here: | |
134 * | |
135 * "manager" - A manager contains one or more isolates, schedules their | |
136 * execution, and performs other plumbing on their behalf. The isolate | |
137 * present at the creation of the manager is designated as its "root isolate". | |
138 * A manager may, for example, be implemented on a web Worker. | |
139 * | |
140 * [_Manager] - State present within a manager (exactly once, as a global). | |
141 * | |
142 * [_ManagerStub] - A handle held within one manager that allows interaction | |
143 * with another manager. A target manager may be addressed by zero or more | |
144 * [_ManagerStub]s. | |
145 * TODO(ahe): The _ManagerStub concept is broken. It was an attempt | |
146 * to create a common interface between the native Worker class and | |
147 * _MainManagerStub. | |
148 */ | |
149 | |
150 /** | |
151 * A native object that is shared across isolates. This object is visible to all | |
152 * isolates running under the same manager (either UI or background web worker). | |
153 * | |
154 * This is code that is intended to 'escape' the isolate boundaries in order to | |
155 * implement the semantics of isolates in JavaScript. Without this we would have | |
156 * been forced to implement more code (including the top-level event loop) in | |
157 * JavaScript itself. | |
158 */ | |
159 // TODO(eub, sigmund): move the "manager" to be entirely in JS. | |
160 // Running any Dart code outside the context of an isolate gives it | |
161 // the chance to break the isolate abstraction. | |
162 _Manager get _globalState => JS("_Manager", "init.globalState"); | |
163 | |
164 set _globalState(_Manager val) { | |
165 JS("void", "init.globalState = #", val); | |
166 } | |
167 | |
168 /** State associated with the current manager. See [globalState]. */ | |
169 // TODO(sigmund): split in multiple classes: global, thread, main-worker states? | |
170 class _Manager { | |
171 | |
172 /** Next available isolate id within this [_Manager]. */ | |
173 int nextIsolateId = 0; | |
174 | |
175 /** id assigned to this [_Manager]. */ | |
176 int currentManagerId = 0; | |
177 | |
178 /** | |
179 * Next available manager id. Only used by the main manager to assign a unique | |
180 * id to each manager created by it. | |
181 */ | |
182 int nextManagerId = 1; | |
183 | |
184 /** Context for the currently running [Isolate]. */ | |
185 _IsolateContext currentContext = null; | |
186 | |
187 /** Context for the root [Isolate] that first run in this [_Manager]. */ | |
188 _IsolateContext rootContext = null; | |
189 | |
190 /** The top-level event loop. */ | |
191 _EventLoop topEventLoop; | |
192 | |
193 /** Whether this program is running from the command line. */ | |
194 bool fromCommandLine; | |
195 | |
196 /** Whether this [_Manager] is running as a web worker. */ | |
197 bool isWorker; | |
198 | |
199 /** Whether we support spawning web workers. */ | |
200 bool supportsWorkers; | |
201 | |
202 /** | |
203 * Whether to use web workers when implementing isolates. Set to false for | |
204 * debugging/testing. | |
205 */ | |
206 bool get useWorkers => supportsWorkers; | |
207 | |
208 /** | |
209 * Registry of isolates. Isolates must be registered if, and only if, receive | |
210 * ports are alive. Normally no open receive-ports means that the isolate is | |
211 * dead, but DOM callbacks could resurrect it. | |
212 */ | |
213 Map<int, _IsolateContext> isolates; | |
214 | |
215 /** Reference to the main [_Manager]. Null in the main [_Manager] itself. */ | |
216 _MainManagerStub mainManager; | |
217 | |
218 /// Registry of active Web Workers. Only used in the main [_Manager]. | |
219 Map<int, dynamic /* Worker */> managers; | |
220 | |
221 /** The entry point given by [startRootIsolate]. */ | |
222 final Function entry; | |
223 | |
224 _Manager(this.entry) { | |
225 _nativeDetectEnvironment(); | |
226 topEventLoop = new _EventLoop(); | |
227 isolates = new Map<int, _IsolateContext>(); | |
228 managers = new Map<int, dynamic>(); | |
229 if (isWorker) { // "if we are not the main manager ourself" is the intent. | |
230 mainManager = new _MainManagerStub(); | |
231 _nativeInitWorkerMessageHandler(); | |
232 } | |
233 } | |
234 | |
235 void _nativeDetectEnvironment() { | |
236 bool isWindowDefined = globalWindow != null; | |
237 bool isWorkerDefined = globalWorker != null; | |
238 | |
239 isWorker = !isWindowDefined && globalPostMessageDefined; | |
240 supportsWorkers = isWorker | |
241 || (isWorkerDefined && IsolateNatives.thisScript != null); | |
242 fromCommandLine = !isWindowDefined && !isWorker; | |
243 } | |
244 | |
245 void _nativeInitWorkerMessageHandler() { | |
246 var function = JS('', | |
247 "(function (f, a) { return function (e) { f(a, e); }})(#, #)", | |
248 DART_CLOSURE_TO_JS(IsolateNatives._processWorkerMessage), | |
249 mainManager); | |
250 JS("void", r"self.onmessage = #", function); | |
251 // We ensure dartPrint is defined so that the implementation of the Dart | |
252 // print method knows what to call. | |
253 JS('', '''self.dartPrint = self.dartPrint || (function(serialize) { | |
254 return function (object) { | |
255 if (self.console && self.console.log) { | |
256 self.console.log(object) | |
257 } else { | |
258 self.postMessage(serialize(object)); | |
259 } | |
260 } | |
261 })(#)''', DART_CLOSURE_TO_JS(_serializePrintMessage)); | |
262 } | |
263 | |
264 static _serializePrintMessage(object) { | |
265 return _serializeMessage({"command": "print", "msg": object}); | |
266 } | |
267 | |
268 /** | |
269 * Close the worker running this code if all isolates are done and | |
270 * there are no active async JavaScript tasks still running. | |
271 */ | |
272 void maybeCloseWorker() { | |
273 if (isWorker | |
274 && isolates.isEmpty | |
275 && topEventLoop._activeJsAsyncCount == 0) { | |
276 mainManager.postMessage(_serializeMessage({'command': 'close'})); | |
277 } | |
278 } | |
279 } | |
280 | |
281 /** Context information tracked for each isolate. */ | |
282 class _IsolateContext implements IsolateContext { | |
283 /** Current isolate id. */ | |
284 final int id = _globalState.nextIsolateId++; | |
285 | |
286 /** Registry of receive ports currently active on this isolate. */ | |
287 final Map<int, RawReceivePortImpl> ports = new Map<int, RawReceivePortImpl>(); | |
288 | |
289 /** Registry of weak receive ports currently active on this isolate. */ | |
290 final Set<int> weakPorts = new Set<int>(); | |
291 | |
292 /** Holds isolate globals (statics and top-level properties). */ | |
293 // native object containing all globals of an isolate. | |
294 final isolateStatics = | |
295 JS('', "#()", JS_EMBEDDED_GLOBAL('', CREATE_NEW_ISOLATE)); | |
296 | |
297 final RawReceivePortImpl controlPort = new RawReceivePortImpl._controlPort(); | |
298 | |
299 final Capability pauseCapability = new Capability(); | |
300 final Capability terminateCapability = new Capability(); // License to kill. | |
301 | |
302 /// Boolean flag set when the initial method of the isolate has been executed. | |
303 /// | |
304 /// Used to avoid considering the isolate dead when it has no open | |
305 /// receive ports and no scheduled timers, because it hasn't had time to | |
306 /// create them yet. | |
307 bool initialized = false; | |
308 | |
309 // TODO(lrn): Store these in single "PauseState" object, so they don't take | |
310 // up as much room when not pausing. | |
311 bool isPaused = false; | |
312 List<_IsolateEvent> delayedEvents = []; | |
313 Set<Capability> pauseTokens = new Set(); | |
314 | |
315 // Container with the "on exit" handler send-ports and responses. | |
316 var doneHandlers; | |
317 | |
318 /** | |
319 * Queue of functions to call when the current event is complete. | |
320 * | |
321 * These events are not just put at the front of the event queue, because | |
322 * they represent control messages, and should be handled even if the | |
323 * event queue is paused. | |
324 */ | |
325 var _scheduledControlEvents; | |
326 bool _isExecutingEvent = false; | |
327 | |
328 /** Whether uncaught errors are considered fatal. */ | |
329 bool errorsAreFatal = true; | |
330 | |
331 // Set of ports that listen to uncaught errors. | |
332 Set<SendPort> errorPorts = new Set(); | |
333 | |
334 _IsolateContext() { | |
335 this.registerWeak(controlPort._id, controlPort); | |
336 } | |
337 | |
338 void addPause(Capability authentification, Capability resume) { | |
339 if (pauseCapability != authentification) return; | |
340 if (pauseTokens.add(resume) && !isPaused) { | |
341 isPaused = true; | |
342 } | |
343 _updateGlobalState(); | |
344 } | |
345 | |
346 void removePause(Capability resume) { | |
347 if (!isPaused) return; | |
348 pauseTokens.remove(resume); | |
349 if (pauseTokens.isEmpty) { | |
350 while(delayedEvents.isNotEmpty) { | |
351 _IsolateEvent event = delayedEvents.removeLast(); | |
352 _globalState.topEventLoop.prequeue(event); | |
353 } | |
354 isPaused = false; | |
355 } | |
356 _updateGlobalState(); | |
357 } | |
358 | |
359 void addDoneListener(SendPort responsePort, Object response) { | |
360 if (doneHandlers == null) { | |
361 doneHandlers = []; | |
362 } | |
363 for (int i = 0; i < doneHandlers.length; i += 2) { | |
364 if (responsePort == doneHandlers[i]) { | |
365 doneHandlers[i + 1] = response; | |
366 return; | |
367 } | |
368 } | |
369 doneHandlers.add(responsePort); | |
370 doneHandlers.add(response); | |
371 } | |
372 | |
373 void removeDoneListener(SendPort responsePort) { | |
374 if (doneHandlers == null) return; | |
375 for (int i = 0; i < doneHandlers.length; i += 2) { | |
376 if (responsePort == doneHandlers[i]) { | |
377 doneHandlers.removeRange(i, i + 2); | |
378 return; | |
379 } | |
380 } | |
381 } | |
382 | |
383 void setErrorsFatal(Capability authentification, bool errorsAreFatal) { | |
384 if (terminateCapability != authentification) return; | |
385 this.errorsAreFatal = errorsAreFatal; | |
386 } | |
387 | |
388 void handlePing(SendPort responsePort, int pingType, Object response) { | |
389 if (pingType == Isolate.IMMEDIATE || | |
390 (pingType == Isolate.BEFORE_NEXT_EVENT && | |
391 !_isExecutingEvent)) { | |
392 responsePort.send(response); | |
393 return; | |
394 } | |
395 void respond() { responsePort.send(response); } | |
396 assert(pingType == Isolate.BEFORE_NEXT_EVENT); | |
397 if (_scheduledControlEvents == null) { | |
398 _scheduledControlEvents = new Queue(); | |
399 } | |
400 _scheduledControlEvents.addLast(respond); | |
401 } | |
402 | |
403 void handleKill(Capability authentification, int priority) { | |
404 if (this.terminateCapability != authentification) return; | |
405 if (priority == Isolate.IMMEDIATE || | |
406 (priority == Isolate.BEFORE_NEXT_EVENT && | |
407 !_isExecutingEvent)) { | |
408 kill(); | |
409 return; | |
410 } | |
411 assert(priority == Isolate.BEFORE_NEXT_EVENT); | |
412 if (_scheduledControlEvents == null) { | |
413 _scheduledControlEvents = new Queue(); | |
414 } | |
415 _scheduledControlEvents.addLast(kill); | |
416 } | |
417 | |
418 void addErrorListener(SendPort port) { | |
419 errorPorts.add(port); | |
420 } | |
421 | |
422 void removeErrorListener(SendPort port) { | |
423 errorPorts.remove(port); | |
424 } | |
425 | |
426 /** Function called with an uncaught error. */ | |
427 void handleUncaughtError(error, StackTrace stackTrace) { | |
428 // Just print the error if there is no error listener registered. | |
429 if (errorPorts.isEmpty) { | |
430 // An uncaught error in the root isolate will terminate the program? | |
431 if (errorsAreFatal && identical(this, _globalState.rootContext)) { | |
432 // The error will be rethrown to reach the global scope, so | |
433 // don't print it. | |
434 return; | |
435 } | |
436 if (JS('bool', 'self.console && self.console.error')) { | |
437 JS('void', 'self.console.error(#, #)', error, stackTrace); | |
438 } else { | |
439 print(error); | |
440 if (stackTrace != null) print(stackTrace); | |
441 } | |
442 return; | |
443 } | |
444 List message = new List(2) | |
445 ..[0] = error.toString() | |
446 ..[1] = (stackTrace == null) ? null : stackTrace.toString(); | |
447 for (SendPort port in errorPorts) port.send(message); | |
448 } | |
449 | |
450 /** | |
451 * Run [code] in the context of the isolate represented by [this]. | |
452 */ | |
453 dynamic eval(Function code) { | |
454 var old = _globalState.currentContext; | |
455 _globalState.currentContext = this; | |
456 this._setGlobals(); | |
457 var result = null; | |
458 var oldIsExecutingEvent = _isExecutingEvent; | |
459 _isExecutingEvent = true; | |
460 try { | |
461 result = code(); | |
462 } catch (e, s) { | |
463 handleUncaughtError(e, s); | |
464 if (errorsAreFatal) { | |
465 kill(); | |
466 // An uncaught error in the root context terminates all isolates. | |
467 if (identical(this, _globalState.rootContext)) { | |
468 rethrow; | |
469 } | |
470 } | |
471 } finally { | |
472 _isExecutingEvent = oldIsExecutingEvent; | |
473 _globalState.currentContext = old; | |
474 if (old != null) old._setGlobals(); | |
475 if (_scheduledControlEvents != null) { | |
476 while (_scheduledControlEvents.isNotEmpty) { | |
477 (_scheduledControlEvents.removeFirst())(); | |
478 } | |
479 } | |
480 } | |
481 return result; | |
482 } | |
483 | |
484 void _setGlobals() { | |
485 JS_SET_CURRENT_ISOLATE(isolateStatics); | |
486 } | |
487 | |
488 /** | |
489 * Handle messages comming in on the control port. | |
490 * | |
491 * These events do not go through the event queue. | |
492 * The `_globalState.currentContext` context is not set to this context | |
493 * during the handling. | |
494 */ | |
495 void handleControlMessage(message) { | |
496 switch (message[0]) { | |
497 case "pause": | |
498 addPause(message[1], message[2]); | |
499 break; | |
500 case "resume": | |
501 removePause(message[1]); | |
502 break; | |
503 case 'add-ondone': | |
504 addDoneListener(message[1], message[2]); | |
505 break; | |
506 case 'remove-ondone': | |
507 removeDoneListener(message[1]); | |
508 break; | |
509 case 'set-errors-fatal': | |
510 setErrorsFatal(message[1], message[2]); | |
511 break; | |
512 case "ping": | |
513 handlePing(message[1], message[2], message[3]); | |
514 break; | |
515 case "kill": | |
516 handleKill(message[1], message[2]); | |
517 break; | |
518 case "getErrors": | |
519 addErrorListener(message[1]); | |
520 break; | |
521 case "stopErrors": | |
522 removeErrorListener(message[1]); | |
523 break; | |
524 default: | |
525 } | |
526 } | |
527 | |
528 /** Looks up a port registered for this isolate. */ | |
529 RawReceivePortImpl lookup(int portId) => ports[portId]; | |
530 | |
531 void _addRegistration(int portId, RawReceivePortImpl port) { | |
532 if (ports.containsKey(portId)) { | |
533 throw new Exception("Registry: ports must be registered only once."); | |
534 } | |
535 ports[portId] = port; | |
536 } | |
537 | |
538 /** Registers a port on this isolate. */ | |
539 void register(int portId, RawReceivePortImpl port) { | |
540 _addRegistration(portId, port); | |
541 _updateGlobalState(); | |
542 } | |
543 | |
544 /** | |
545 * Registers a weak port on this isolate. | |
546 * | |
547 * The port does not keep the isolate active. | |
548 */ | |
549 void registerWeak(int portId, RawReceivePortImpl port) { | |
550 weakPorts.add(portId); | |
551 _addRegistration(portId, port); | |
552 } | |
553 | |
554 void _updateGlobalState() { | |
555 if (ports.length - weakPorts.length > 0 || isPaused || !initialized) { | |
556 _globalState.isolates[id] = this; // indicate this isolate is active | |
557 } else { | |
558 kill(); | |
559 } | |
560 } | |
561 | |
562 void kill() { | |
563 if (_scheduledControlEvents != null) { | |
564 // Kill all pending events. | |
565 _scheduledControlEvents.clear(); | |
566 } | |
567 // Stop listening on all ports. | |
568 // This should happen before sending events to done handlers, in case | |
569 // we are listening on ourselves. | |
570 // Closes all ports, including control port. | |
571 for (var port in ports.values) { | |
572 port._close(); | |
573 } | |
574 ports.clear(); | |
575 weakPorts.clear(); | |
576 _globalState.isolates.remove(id); // indicate this isolate is not active | |
577 errorPorts.clear(); | |
578 if (doneHandlers != null) { | |
579 for (int i = 0; i < doneHandlers.length; i += 2) { | |
580 SendPort responsePort = doneHandlers[i]; | |
581 Object response = doneHandlers[i + 1]; | |
582 responsePort.send(response); | |
583 } | |
584 doneHandlers = null; | |
585 } | |
586 } | |
587 | |
588 /** Unregister a port on this isolate. */ | |
589 void unregister(int portId) { | |
590 ports.remove(portId); | |
591 weakPorts.remove(portId); | |
592 _updateGlobalState(); | |
593 } | |
594 } | |
595 | |
596 /** Represent the event loop on a javascript thread (DOM or worker). */ | |
597 class _EventLoop { | |
598 final Queue<_IsolateEvent> events = new Queue<_IsolateEvent>(); | |
599 | |
600 /// The number of waiting callbacks not controlled by the dart event loop. | |
601 /// | |
602 /// This could be timers or http requests. The worker will only be killed if | |
603 /// this count reaches 0. | |
604 /// Access this by using [enterJsAsync] before starting a JavaScript async | |
605 /// operation and [leaveJsAsync] when the callback has fired. | |
606 int _activeJsAsyncCount = 0; | |
607 | |
608 _EventLoop(); | |
609 | |
610 void enqueue(isolate, fn, msg) { | |
611 events.addLast(new _IsolateEvent(isolate, fn, msg)); | |
612 } | |
613 | |
614 void prequeue(_IsolateEvent event) { | |
615 events.addFirst(event); | |
616 } | |
617 | |
618 _IsolateEvent dequeue() { | |
619 if (events.isEmpty) return null; | |
620 return events.removeFirst(); | |
621 } | |
622 | |
623 void checkOpenReceivePortsFromCommandLine() { | |
624 if (_globalState.rootContext != null | |
625 && _globalState.isolates.containsKey(_globalState.rootContext.id) | |
626 && _globalState.fromCommandLine | |
627 && _globalState.rootContext.ports.isEmpty) { | |
628 // We want to reach here only on the main [_Manager] and only | |
629 // on the command-line. In the browser the isolate might | |
630 // still be alive due to DOM callbacks, but the presumption is | |
631 // that on the command-line, no future events can be injected | |
632 // into the event queue once it's empty. Node has setTimeout | |
633 // so this presumption is incorrect there. We think(?) that | |
634 // in d8 this assumption is valid. | |
635 throw new Exception("Program exited with open ReceivePorts."); | |
636 } | |
637 } | |
638 | |
639 /** Process a single event, if any. */ | |
640 bool runIteration() { | |
641 final event = dequeue(); | |
642 if (event == null) { | |
643 checkOpenReceivePortsFromCommandLine(); | |
644 _globalState.maybeCloseWorker(); | |
645 return false; | |
646 } | |
647 event.process(); | |
648 return true; | |
649 } | |
650 | |
651 /** | |
652 * Runs multiple iterations of the run-loop. If possible, each iteration is | |
653 * run asynchronously. | |
654 */ | |
655 void _runHelper() { | |
656 if (globalWindow != null) { | |
657 // Run each iteration from the browser's top event loop. | |
658 void next() { | |
659 if (!runIteration()) return; | |
660 Timer.run(next); | |
661 } | |
662 next(); | |
663 } else { | |
664 // Run synchronously until no more iterations are available. | |
665 while (runIteration()) {} | |
666 } | |
667 } | |
668 | |
669 /** | |
670 * Call [_runHelper] but ensure that worker exceptions are propagated. | |
671 */ | |
672 void run() { | |
673 if (!_globalState.isWorker) { | |
674 _runHelper(); | |
675 } else { | |
676 try { | |
677 _runHelper(); | |
678 } catch (e, trace) { | |
679 _globalState.mainManager.postMessage(_serializeMessage( | |
680 {'command': 'error', 'msg': '$e\n$trace' })); | |
681 } | |
682 } | |
683 } | |
684 } | |
685 | |
686 /** An event in the top-level event queue. */ | |
687 class _IsolateEvent { | |
688 _IsolateContext isolate; | |
689 Function fn; | |
690 String message; | |
691 | |
692 _IsolateEvent(this.isolate, this.fn, this.message); | |
693 | |
694 void process() { | |
695 if (isolate.isPaused) { | |
696 isolate.delayedEvents.add(this); | |
697 return; | |
698 } | |
699 isolate.eval(fn); | |
700 } | |
701 } | |
702 | |
703 /** A stub for interacting with the main manager. */ | |
704 class _MainManagerStub { | |
705 void postMessage(msg) { | |
706 // "self" is a way to refer to the global context object that | |
707 // works in HTML pages and in Web Workers. It does not work in d8 | |
708 // and Firefox jsshell, because that would have been too easy. | |
709 // | |
710 // See: http://www.w3.org/TR/workers/#the-global-scope | |
711 // and: http://www.w3.org/TR/Window/#dfn-self-attribute | |
712 requiresPreamble(); | |
713 JS("void", r"self.postMessage(#)", msg); | |
714 } | |
715 } | |
716 | |
717 const String _SPAWNED_SIGNAL = "spawned"; | |
718 const String _SPAWN_FAILED_SIGNAL = "spawn failed"; | |
719 | |
720 get globalWindow { | |
721 requiresPreamble(); | |
722 return JS('', "self.window"); | |
723 } | |
724 | |
725 get globalWorker { | |
726 requiresPreamble(); | |
727 return JS('', "self.Worker"); | |
728 } | |
729 bool get globalPostMessageDefined { | |
730 requiresPreamble(); | |
731 return JS('bool', "!!self.postMessage"); | |
732 } | |
733 | |
734 typedef _MainFunction(); | |
735 typedef _MainFunctionArgs(args); | |
736 typedef _MainFunctionArgsMessage(args, message); | |
737 | |
738 /// Note: IsolateNatives depends on _globalState which is only set up correctly | |
739 /// when 'dart:isolate' has been imported. | |
740 class IsolateNatives { | |
741 | |
742 // We set [enableSpawnWorker] to true (not null) when calling isolate | |
743 // primitives that require support for spawning workers. The field starts out | |
744 // by being null, and dart2js' type inference will track if it can have a | |
745 // non-null value. So by testing if this value is not null, we generate code | |
746 // that dart2js knows is dead when worker support isn't needed. | |
747 // TODO(herhut): Initialize this to false when able to track compile-time | |
748 // constants. | |
749 static var enableSpawnWorker; | |
750 | |
751 static String thisScript = computeThisScript(); | |
752 | |
753 /// Associates an ID with a native worker object. | |
754 static final Expando<int> workerIds = new Expando<int>(); | |
755 | |
756 /** | |
757 * The src url for the script tag that loaded this function. | |
758 * | |
759 * Used to create JavaScript workers and load deferred libraries. | |
760 */ | |
761 static String computeThisScript() { | |
762 var currentScript = JS_EMBEDDED_GLOBAL('', CURRENT_SCRIPT); | |
763 if (currentScript != null) { | |
764 return JS('String', 'String(#.src)', currentScript); | |
765 } | |
766 // A worker has no script tag - so get an url from a stack-trace. | |
767 if (_globalState.isWorker) return computeThisScriptFromTrace(); | |
768 return null; | |
769 } | |
770 | |
771 static String computeThisScriptFromTrace() { | |
772 var stack = JS('String|Null', 'new Error().stack'); | |
773 if (stack == null) { | |
774 // According to Internet Explorer documentation, the stack | |
775 // property is not set until the exception is thrown. The stack | |
776 // property was not provided until IE10. | |
777 stack = JS('String|Null', | |
778 '(function() {' | |
779 'try { throw new Error() } catch(e) { return e.stack }' | |
780 '})()'); | |
781 if (stack == null) throw new UnsupportedError('No stack trace'); | |
782 } | |
783 var pattern, matches; | |
784 | |
785 // This pattern matches V8, Chrome, and Internet Explorer stack | |
786 // traces that look like this: | |
787 // Error | |
788 // at methodName (URI:LINE:COLUMN) | |
789 pattern = JS('', | |
790 r'new RegExp("^ *at [^(]*\\((.*):[0-9]*:[0-9]*\\)$", "m")'); | |
791 | |
792 | |
793 matches = JS('JSExtendableArray|Null', '#.match(#)', stack, pattern); | |
794 if (matches != null) return JS('String', '#[1]', matches); | |
795 | |
796 // This pattern matches Firefox stack traces that look like this: | |
797 // methodName@URI:LINE | |
798 pattern = JS('', r'new RegExp("^[^@]*@(.*):[0-9]*$", "m")'); | |
799 | |
800 matches = JS('JSExtendableArray|Null', '#.match(#)', stack, pattern); | |
801 if (matches != null) return JS('String', '#[1]', matches); | |
802 | |
803 throw new UnsupportedError('Cannot extract URI from "$stack"'); | |
804 } | |
805 | |
806 /** | |
807 * Assume that [e] is a browser message event and extract its message data. | |
808 * We don't import the dom explicitly so, when workers are disabled, this | |
809 * library can also run on top of nodejs. | |
810 */ | |
811 static _getEventData(e) => JS("", "#.data", e); | |
812 | |
813 /** | |
814 * Process messages on a worker, either to control the worker instance or to | |
815 * pass messages along to the isolate running in the worker. | |
816 */ | |
817 static void _processWorkerMessage(/* Worker */ sender, e) { | |
818 var msg = _deserializeMessage(_getEventData(e)); | |
819 switch (msg['command']) { | |
820 case 'start': | |
821 _globalState.currentManagerId = msg['id']; | |
822 String functionName = msg['functionName']; | |
823 Function entryPoint = (functionName == null) | |
824 ? _globalState.entry | |
825 : _getJSFunctionFromName(functionName); | |
826 var args = msg['args']; | |
827 var message = _deserializeMessage(msg['msg']); | |
828 var isSpawnUri = msg['isSpawnUri']; | |
829 var startPaused = msg['startPaused']; | |
830 var replyTo = _deserializeMessage(msg['replyTo']); | |
831 var context = new _IsolateContext(); | |
832 _globalState.topEventLoop.enqueue(context, () { | |
833 _startIsolate(entryPoint, args, message, | |
834 isSpawnUri, startPaused, replyTo); | |
835 }, 'worker-start'); | |
836 // Make sure we always have a current context in this worker. | |
837 // TODO(7907): This is currently needed because we're using | |
838 // Timers to implement Futures, and this isolate library | |
839 // implementation uses Futures. We should either stop using | |
840 // Futures in this library, or re-adapt if Futures get a | |
841 // different implementation. | |
842 _globalState.currentContext = context; | |
843 _globalState.topEventLoop.run(); | |
844 break; | |
845 case 'spawn-worker': | |
846 if (enableSpawnWorker != null) handleSpawnWorkerRequest(msg); | |
847 break; | |
848 case 'message': | |
849 SendPort port = msg['port']; | |
850 // If the port has been closed, we ignore the message. | |
851 if (port != null) { | |
852 msg['port'].send(msg['msg']); | |
853 } | |
854 _globalState.topEventLoop.run(); | |
855 break; | |
856 case 'close': | |
857 _globalState.managers.remove(workerIds[sender]); | |
858 JS('void', '#.terminate()', sender); | |
859 _globalState.topEventLoop.run(); | |
860 break; | |
861 case 'log': | |
862 _log(msg['msg']); | |
863 break; | |
864 case 'print': | |
865 if (_globalState.isWorker) { | |
866 _globalState.mainManager.postMessage( | |
867 _serializeMessage({'command': 'print', 'msg': msg})); | |
868 } else { | |
869 print(msg['msg']); | |
870 } | |
871 break; | |
872 case 'error': | |
873 throw msg['msg']; | |
874 } | |
875 } | |
876 | |
877 static handleSpawnWorkerRequest(msg) { | |
878 var replyPort = msg['replyPort']; | |
879 spawn(msg['functionName'], msg['uri'], | |
880 msg['args'], msg['msg'], | |
881 false, msg['isSpawnUri'], msg['startPaused']).then((msg) { | |
882 replyPort.send(msg); | |
883 }, onError: (String errorMessage) { | |
884 replyPort.send([_SPAWN_FAILED_SIGNAL, errorMessage]); | |
885 }); | |
886 } | |
887 | |
888 /** Log a message, forwarding to the main [_Manager] if appropriate. */ | |
889 static _log(msg) { | |
890 if (_globalState.isWorker) { | |
891 _globalState.mainManager.postMessage( | |
892 _serializeMessage({'command': 'log', 'msg': msg })); | |
893 } else { | |
894 try { | |
895 _consoleLog(msg); | |
896 } catch (e, trace) { | |
897 throw new Exception(trace); | |
898 } | |
899 } | |
900 } | |
901 | |
902 static void _consoleLog(msg) { | |
903 requiresPreamble(); | |
904 JS("void", r"self.console.log(#)", msg); | |
905 } | |
906 | |
907 static _getJSFunctionFromName(String functionName) { | |
908 var globalFunctionsContainer = JS_EMBEDDED_GLOBAL("", GLOBAL_FUNCTIONS); | |
909 return JS("", "#[#]()", globalFunctionsContainer, functionName); | |
910 } | |
911 | |
912 /** | |
913 * Get a string name for the function, if possible. The result for | |
914 * anonymous functions is browser-dependent -- it may be "" or "anonymous" | |
915 * but you should probably not count on this. | |
916 */ | |
917 static String _getJSFunctionName(Function f) { | |
918 return (f is Closure) ? JS("String|Null", r'#.$name', f) : null; | |
919 } | |
920 | |
921 /** Create a new JavaScript object instance given its constructor. */ | |
922 static dynamic _allocate(var ctor) { | |
923 return JS("", "new #()", ctor); | |
924 } | |
925 | |
926 static Future<List> spawnFunction(void topLevelFunction(message), | |
927 var message, | |
928 bool startPaused) { | |
929 IsolateNatives.enableSpawnWorker = true; | |
930 final name = _getJSFunctionName(topLevelFunction); | |
931 if (name == null) { | |
932 throw new UnsupportedError( | |
933 "only top-level functions can be spawned."); | |
934 } | |
935 bool isLight = false; | |
936 bool isSpawnUri = false; | |
937 return spawn(name, null, null, message, isLight, isSpawnUri, startPaused); | |
938 } | |
939 | |
940 static Future<List> spawnUri(Uri uri, List<String> args, var message, | |
941 bool startPaused) { | |
942 IsolateNatives.enableSpawnWorker = true; | |
943 bool isLight = false; | |
944 bool isSpawnUri = true; | |
945 return spawn(null, uri.toString(), args, message, | |
946 isLight, isSpawnUri, startPaused); | |
947 } | |
948 | |
949 // TODO(sigmund): clean up above, after we make the new API the default: | |
950 | |
951 /// If [uri] is `null` it is replaced with the current script. | |
952 static Future<List> spawn(String functionName, String uri, | |
953 List<String> args, message, | |
954 bool isLight, bool isSpawnUri, bool startPaused) { | |
955 // Assume that the compiled version of the Dart file lives just next to the | |
956 // dart file. | |
957 // TODO(floitsch): support precompiled version of dart2js output. | |
958 if (uri != null && uri.endsWith(".dart")) uri += ".js"; | |
959 | |
960 ReceivePort port = new ReceivePort(); | |
961 Completer<List> completer = new Completer(); | |
962 port.first.then((msg) { | |
963 if (msg[0] == _SPAWNED_SIGNAL) { | |
964 completer.complete(msg); | |
965 } else { | |
966 assert(msg[0] == _SPAWN_FAILED_SIGNAL); | |
967 completer.completeError(msg[1]); | |
968 } | |
969 }); | |
970 | |
971 SendPort signalReply = port.sendPort; | |
972 | |
973 if (_globalState.useWorkers && !isLight) { | |
974 _startWorker( | |
975 functionName, uri, args, message, isSpawnUri, startPaused, | |
976 signalReply, (String message) => completer.completeError(message)); | |
977 } else { | |
978 _startNonWorker( | |
979 functionName, uri, args, message, isSpawnUri, startPaused, | |
980 signalReply); | |
981 } | |
982 return completer.future; | |
983 } | |
984 | |
985 static void _startWorker( | |
986 String functionName, String uri, | |
987 List<String> args, message, | |
988 bool isSpawnUri, | |
989 bool startPaused, | |
990 SendPort replyPort, | |
991 void onError(String message)) { | |
992 // Make sure that the args list is a fresh generic list. A newly spawned | |
993 // isolate should be able to assume that the arguments list is an | |
994 // extendable list. | |
995 if (args != null) args = new List<String>.from(args); | |
996 if (_globalState.isWorker) { | |
997 _globalState.mainManager.postMessage(_serializeMessage({ | |
998 'command': 'spawn-worker', | |
999 'functionName': functionName, | |
1000 'args': args, | |
1001 'msg': message, | |
1002 'uri': uri, | |
1003 'isSpawnUri': isSpawnUri, | |
1004 'startPaused': startPaused, | |
1005 'replyPort': replyPort})); | |
1006 } else { | |
1007 _spawnWorker(functionName, uri, args, message, | |
1008 isSpawnUri, startPaused, replyPort, onError); | |
1009 } | |
1010 } | |
1011 | |
1012 static void _startNonWorker( | |
1013 String functionName, String uri, | |
1014 List<String> args, var message, | |
1015 bool isSpawnUri, | |
1016 bool startPaused, | |
1017 SendPort replyPort) { | |
1018 // TODO(eub): support IE9 using an iframe -- Dart issue 1702. | |
1019 if (uri != null) { | |
1020 throw new UnsupportedError( | |
1021 "Currently spawnUri is not supported without web workers."); | |
1022 } | |
1023 // Clone the message to enforce the restrictions we have on isolate | |
1024 // messages. | |
1025 message = _clone(message); | |
1026 // Make sure that the args list is a fresh generic list. A newly spawned | |
1027 // isolate should be able to assume that the arguments list is an | |
1028 // extendable list. | |
1029 if (args != null) args = new List<String>.from(args); | |
1030 _globalState.topEventLoop.enqueue(new _IsolateContext(), () { | |
1031 final func = _getJSFunctionFromName(functionName); | |
1032 _startIsolate(func, args, message, isSpawnUri, startPaused, replyPort); | |
1033 }, 'nonworker start'); | |
1034 } | |
1035 | |
1036 static Isolate get currentIsolate { | |
1037 _IsolateContext context = JS_CURRENT_ISOLATE_CONTEXT(); | |
1038 return new Isolate(context.controlPort.sendPort, | |
1039 pauseCapability: context.pauseCapability, | |
1040 terminateCapability: context.terminateCapability); | |
1041 } | |
1042 | |
1043 static void _startIsolate(Function topLevel, | |
1044 List<String> args, message, | |
1045 bool isSpawnUri, | |
1046 bool startPaused, | |
1047 SendPort replyTo) { | |
1048 _IsolateContext context = JS_CURRENT_ISOLATE_CONTEXT(); | |
1049 Primitives.initializeStatics(context.id); | |
1050 // The isolate's port does not keep the isolate open. | |
1051 replyTo.send([_SPAWNED_SIGNAL, | |
1052 context.controlPort.sendPort, | |
1053 context.pauseCapability, | |
1054 context.terminateCapability]); | |
1055 | |
1056 void runStartFunction() { | |
1057 context.initialized = true; | |
1058 if (!isSpawnUri) { | |
1059 topLevel(message); | |
1060 } else if (topLevel is _MainFunctionArgsMessage) { | |
1061 topLevel(args, message); | |
1062 } else if (topLevel is _MainFunctionArgs) { | |
1063 topLevel(args); | |
1064 } else { | |
1065 topLevel(); | |
1066 } | |
1067 } | |
1068 | |
1069 if (startPaused) { | |
1070 context.addPause(context.pauseCapability, context.pauseCapability); | |
1071 _globalState.topEventLoop.enqueue(context, runStartFunction, | |
1072 'start isolate'); | |
1073 } else { | |
1074 runStartFunction(); | |
1075 } | |
1076 } | |
1077 | |
1078 /** | |
1079 * Spawns an isolate in a worker. [factoryName] is the Javascript constructor | |
1080 * name for the isolate entry point class. | |
1081 */ | |
1082 static void _spawnWorker(functionName, String uri, | |
1083 List<String> args, message, | |
1084 bool isSpawnUri, | |
1085 bool startPaused, | |
1086 SendPort replyPort, | |
1087 void onError(String message)) { | |
1088 if (uri == null) uri = thisScript; | |
1089 final worker = JS('var', 'new Worker(#)', uri); | |
1090 // Trampolines are used when wanting to call a Dart closure from | |
1091 // JavaScript. The helper function DART_CLOSURE_TO_JS only accepts | |
1092 // top-level or static methods, and the trampoline allows us to capture | |
1093 // arguments and values which can be passed to a static method. | |
1094 final onerrorTrampoline = JS( | |
1095 '', | |
1096 ''' | |
1097 (function (f, u, c) { | |
1098 return function(e) { | |
1099 return f(e, u, c) | |
1100 } | |
1101 })(#, #, #)''', | |
1102 DART_CLOSURE_TO_JS(workerOnError), uri, onError); | |
1103 JS('void', '#.onerror = #', worker, onerrorTrampoline); | |
1104 | |
1105 var processWorkerMessageTrampoline = JS( | |
1106 '', | |
1107 """ | |
1108 (function (f, a) { | |
1109 return function (e) { | |
1110 // We can stop listening for errors when the first message is received as | |
1111 // we only listen for messages to determine if the uri was bad. | |
1112 e.onerror = null; | |
1113 return f(a, e); | |
1114 } | |
1115 })(#, #)""", | |
1116 DART_CLOSURE_TO_JS(_processWorkerMessage), | |
1117 worker); | |
1118 JS('void', '#.onmessage = #', worker, processWorkerMessageTrampoline); | |
1119 var workerId = _globalState.nextManagerId++; | |
1120 // We also store the id on the worker itself so that we can unregister it. | |
1121 workerIds[worker] = workerId; | |
1122 _globalState.managers[workerId] = worker; | |
1123 JS('void', '#.postMessage(#)', worker, _serializeMessage({ | |
1124 'command': 'start', | |
1125 'id': workerId, | |
1126 // Note: we serialize replyPort twice because the child worker needs to | |
1127 // first deserialize the worker id, before it can correctly deserialize | |
1128 // the port (port deserialization is sensitive to what is the current | |
1129 // workerId). | |
1130 'replyTo': _serializeMessage(replyPort), | |
1131 'args': args, | |
1132 'msg': _serializeMessage(message), | |
1133 'isSpawnUri': isSpawnUri, | |
1134 'startPaused': startPaused, | |
1135 'functionName': functionName })); | |
1136 } | |
1137 | |
1138 static bool workerOnError( | |
1139 /* Event */ event, | |
1140 String uri, | |
1141 void onError(String message)) { | |
1142 // Attempt to shut up the browser, as the error has been handled. Chrome | |
1143 // ignores this :-( | |
1144 JS('void', '#.preventDefault()', event); | |
1145 String message = JS('String|Null', '#.message', event); | |
1146 if (message == null) { | |
1147 // Some browsers, including Chrome, fail to provide a proper error | |
1148 // event. | |
1149 message = 'Error spawning worker for $uri'; | |
1150 } else { | |
1151 message = 'Error spawning worker for $uri ($message)'; | |
1152 } | |
1153 onError(message); | |
1154 return true; | |
1155 } | |
1156 } | |
1157 | |
1158 /******************************************************** | |
1159 Inserted from lib/isolate/dart2js/ports.dart | |
1160 ********************************************************/ | |
1161 | |
1162 /** Common functionality to all send ports. */ | |
1163 abstract class _BaseSendPort implements SendPort { | |
1164 /** Id for the destination isolate. */ | |
1165 final int _isolateId; | |
1166 | |
1167 const _BaseSendPort(this._isolateId); | |
1168 | |
1169 void _checkReplyTo(SendPort replyTo) { | |
1170 if (replyTo != null | |
1171 && replyTo is! _NativeJsSendPort | |
1172 && replyTo is! _WorkerSendPort) { | |
1173 throw new Exception("SendPort.send: Illegal replyTo port type"); | |
1174 } | |
1175 } | |
1176 | |
1177 void send(var message); | |
1178 bool operator ==(var other); | |
1179 int get hashCode; | |
1180 } | |
1181 | |
1182 /** A send port that delivers messages in-memory via native JavaScript calls. */ | |
1183 class _NativeJsSendPort extends _BaseSendPort implements SendPort { | |
1184 final RawReceivePortImpl _receivePort; | |
1185 | |
1186 const _NativeJsSendPort(this._receivePort, int isolateId) : super(isolateId); | |
1187 | |
1188 void send(var message) { | |
1189 // Check that the isolate still runs and the port is still open | |
1190 final isolate = _globalState.isolates[_isolateId]; | |
1191 if (isolate == null) return; | |
1192 if (_receivePort._isClosed) return; | |
1193 // Clone the message to enforce the restrictions we have on isolate | |
1194 // messages. | |
1195 var msg = _clone(message); | |
1196 if (isolate.controlPort == _receivePort) { | |
1197 isolate.handleControlMessage(msg); | |
1198 return; | |
1199 } | |
1200 _globalState.topEventLoop.enqueue(isolate, () { | |
1201 if (!_receivePort._isClosed) { | |
1202 _receivePort._add(msg); | |
1203 } | |
1204 }, 'receive $message'); | |
1205 } | |
1206 | |
1207 bool operator ==(var other) => (other is _NativeJsSendPort) && | |
1208 (_receivePort == other._receivePort); | |
1209 | |
1210 int get hashCode => _receivePort._id; | |
1211 } | |
1212 | |
1213 /** A send port that delivers messages via worker.postMessage. */ | |
1214 // TODO(eub): abstract this for iframes. | |
1215 class _WorkerSendPort extends _BaseSendPort implements SendPort { | |
1216 final int _workerId; | |
1217 final int _receivePortId; | |
1218 | |
1219 const _WorkerSendPort(this._workerId, int isolateId, this._receivePortId) | |
1220 : super(isolateId); | |
1221 | |
1222 void send(var message) { | |
1223 final workerMessage = _serializeMessage({ | |
1224 'command': 'message', | |
1225 'port': this, | |
1226 'msg': message}); | |
1227 | |
1228 if (_globalState.isWorker) { | |
1229 // Communication from one worker to another go through the | |
1230 // main worker. | |
1231 _globalState.mainManager.postMessage(workerMessage); | |
1232 } else { | |
1233 // Deliver the message only if the worker is still alive. | |
1234 /* Worker */ var manager = _globalState.managers[_workerId]; | |
1235 if (manager != null) { | |
1236 JS('void', '#.postMessage(#)', manager, workerMessage); | |
1237 } | |
1238 } | |
1239 } | |
1240 | |
1241 bool operator ==(var other) { | |
1242 return (other is _WorkerSendPort) && | |
1243 (_workerId == other._workerId) && | |
1244 (_isolateId == other._isolateId) && | |
1245 (_receivePortId == other._receivePortId); | |
1246 } | |
1247 | |
1248 int get hashCode { | |
1249 // TODO(sigmund): use a standard hash when we get one available in corelib. | |
1250 return (_workerId << 16) ^ (_isolateId << 8) ^ _receivePortId; | |
1251 } | |
1252 } | |
1253 | |
1254 class RawReceivePortImpl implements RawReceivePort { | |
1255 static int _nextFreeId = 1; | |
1256 | |
1257 final int _id; | |
1258 Function _handler; | |
1259 bool _isClosed = false; | |
1260 | |
1261 RawReceivePortImpl(this._handler) : _id = _nextFreeId++ { | |
1262 _globalState.currentContext.register(_id, this); | |
1263 } | |
1264 | |
1265 RawReceivePortImpl.weak(this._handler) : _id = _nextFreeId++ { | |
1266 _globalState.currentContext.registerWeak(_id, this); | |
1267 } | |
1268 | |
1269 // Creates the control port of an isolate. | |
1270 // This is created before the isolate context object itself, | |
1271 // so it cannot access the static _nextFreeId field. | |
1272 RawReceivePortImpl._controlPort() : _handler = null, _id = 0; | |
1273 | |
1274 void set handler(Function newHandler) { | |
1275 _handler = newHandler; | |
1276 } | |
1277 | |
1278 // Close the port without unregistering it. | |
1279 // Used by an isolate context to close all ports when shutting down. | |
1280 void _close() { | |
1281 _isClosed = true; | |
1282 _handler = null; | |
1283 } | |
1284 | |
1285 void close() { | |
1286 if (_isClosed) return; | |
1287 _isClosed = true; | |
1288 _handler = null; | |
1289 _globalState.currentContext.unregister(_id); | |
1290 } | |
1291 | |
1292 void _add(dataEvent) { | |
1293 if (_isClosed) return; | |
1294 _handler(dataEvent); | |
1295 } | |
1296 | |
1297 SendPort get sendPort { | |
1298 return new _NativeJsSendPort(this, _globalState.currentContext.id); | |
1299 } | |
1300 } | |
1301 | |
1302 class ReceivePortImpl extends Stream implements ReceivePort { | |
1303 final RawReceivePort _rawPort; | |
1304 StreamController _controller; | |
1305 | |
1306 ReceivePortImpl() : this.fromRawReceivePort(new RawReceivePortImpl(null)); | |
1307 | |
1308 ReceivePortImpl.weak() | |
1309 : this.fromRawReceivePort(new RawReceivePortImpl.weak(null)); | |
1310 | |
1311 ReceivePortImpl.fromRawReceivePort(this._rawPort) { | |
1312 _controller = new StreamController(onCancel: close, sync: true); | |
1313 _rawPort.handler = _controller.add; | |
1314 } | |
1315 | |
1316 StreamSubscription listen(void onData(var event), | |
1317 {Function onError, | |
1318 void onDone(), | |
1319 bool cancelOnError}) { | |
1320 return _controller.stream.listen(onData, onError: onError, onDone: onDone, | |
1321 cancelOnError: cancelOnError); | |
1322 } | |
1323 | |
1324 void close() { | |
1325 _rawPort.close(); | |
1326 _controller.close(); | |
1327 } | |
1328 | |
1329 SendPort get sendPort => _rawPort.sendPort; | |
1330 } | |
1331 | |
1332 class TimerImpl implements Timer { | |
1333 final bool _once; | |
1334 bool _inEventLoop = false; | |
1335 int _handle; | |
1336 | |
1337 TimerImpl(int milliseconds, void callback()) | |
1338 : _once = true { | |
1339 if (milliseconds == 0 && (!hasTimer() || _globalState.isWorker)) { | |
1340 | |
1341 void internalCallback() { | |
1342 _handle = null; | |
1343 callback(); | |
1344 } | |
1345 | |
1346 // Setting _handle to something different from null indicates that the | |
1347 // callback has not been run. Hence, the choice of 1 is arbitrary. | |
1348 _handle = 1; | |
1349 | |
1350 // This makes a dependency between the async library and the | |
1351 // event loop of the isolate library. The compiler makes sure | |
1352 // that the event loop is compiled if [Timer] is used. | |
1353 // TODO(7907): In case of web workers, we need to use the event | |
1354 // loop instead of setTimeout, to make sure the futures get executed in | |
1355 // order. | |
1356 _globalState.topEventLoop.enqueue( | |
1357 _globalState.currentContext, internalCallback, 'timer'); | |
1358 _inEventLoop = true; | |
1359 } else if (hasTimer()) { | |
1360 | |
1361 void internalCallback() { | |
1362 _handle = null; | |
1363 leaveJsAsync(); | |
1364 callback(); | |
1365 } | |
1366 | |
1367 enterJsAsync(); | |
1368 | |
1369 _handle = JS('int', 'self.setTimeout(#, #)', | |
1370 convertDartClosureToJS(internalCallback, 0), | |
1371 milliseconds); | |
1372 } else { | |
1373 assert(milliseconds > 0); | |
1374 throw new UnsupportedError("Timer greater than 0."); | |
1375 } | |
1376 } | |
1377 | |
1378 TimerImpl.periodic(int milliseconds, void callback(Timer timer)) | |
1379 : _once = false { | |
1380 if (hasTimer()) { | |
1381 enterJsAsync(); | |
1382 _handle = JS('int', 'self.setInterval(#, #)', | |
1383 convertDartClosureToJS(() { callback(this); }, 0), | |
1384 milliseconds); | |
1385 } else { | |
1386 throw new UnsupportedError("Periodic timer."); | |
1387 } | |
1388 } | |
1389 | |
1390 void cancel() { | |
1391 if (hasTimer()) { | |
1392 if (_inEventLoop) { | |
1393 throw new UnsupportedError("Timer in event loop cannot be canceled."); | |
1394 } | |
1395 if (_handle == null) return; | |
1396 leaveJsAsync(); | |
1397 if (_once) { | |
1398 JS('void', 'self.clearTimeout(#)', _handle); | |
1399 } else { | |
1400 JS('void', 'self.clearInterval(#)', _handle); | |
1401 } | |
1402 _handle = null; | |
1403 } else { | |
1404 throw new UnsupportedError("Canceling a timer."); | |
1405 } | |
1406 } | |
1407 | |
1408 bool get isActive => _handle != null; | |
1409 } | |
1410 | |
1411 bool hasTimer() { | |
1412 requiresPreamble(); | |
1413 return JS('', 'self.setTimeout') != null; | |
1414 } | |
1415 | |
1416 | |
1417 /** | |
1418 * Implementation class for [Capability]. | |
1419 * | |
1420 * It has the same name to make it harder for users to distinguish. | |
1421 */ | |
1422 class CapabilityImpl implements Capability { | |
1423 /** Internal random secret identifying the capability. */ | |
1424 final int _id; | |
1425 | |
1426 CapabilityImpl() : this._internal(random64()); | |
1427 | |
1428 CapabilityImpl._internal(this._id); | |
1429 | |
1430 int get hashCode { | |
1431 // Thomas Wang 32 bit Mix. | |
1432 // http://www.concentric.net/~Ttwang/tech/inthash.htm | |
1433 // (via https://gist.github.com/badboy/6267743) | |
1434 int hash = _id; | |
1435 hash = (hash >> 0) ^ (hash ~/ 0x100000000); // To 32 bit from ~64. | |
1436 hash = (~hash + (hash << 15)) & 0xFFFFFFFF; | |
1437 hash ^= hash >> 12; | |
1438 hash = (hash * 5) & 0xFFFFFFFF; | |
1439 hash ^= hash >> 4; | |
1440 hash = (hash * 2057) & 0xFFFFFFFF; | |
1441 hash ^= hash >> 16; | |
1442 return hash; | |
1443 } | |
1444 | |
1445 bool operator==(Object other) { | |
1446 if (identical(other, this)) return true; | |
1447 if (other is CapabilityImpl) { | |
1448 return identical(_id, other._id); | |
1449 } | |
1450 return false; | |
1451 } | |
1452 } | |
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