Use patching for dart:io.

runtime/bin/timer_impl.dart

-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-class _Timer implements Timer {
-  // Set jitter to wake up timer events that would happen in _TIMER_JITTER ms.
-  static const int _TIMER_JITTER = 0;
-
-  // Disables the timer.
-  static const int _NO_TIMER = -1;
-
-  static Timer _createTimer(void callback(Timer timer),
-                           int milliSeconds,
-                           bool repeating) {
-    _EventHandler._start();
-    if (_timers === null) {
-      _timers = new DoubleLinkedQueue<_Timer>();
-    }
-    Timer timer = new _Timer._internal();
-    timer._callback = callback;
-    timer._milliSeconds = milliSeconds;
-    timer._wakeupTime = (new Date.now()).millisecondsSinceEpoch + milliSeconds;
-    timer._repeating = repeating;
-    timer._addTimerToList();
-    timer._notifyEventHandler();
-    return timer;
-  }
-
-  factory _Timer(int milliSeconds, void callback(Timer timer)) {
-    return _createTimer(callback, milliSeconds, false);
-  }
-
-  factory _Timer.repeating(int milliSeconds, void callback(Timer timer)) {
-    return _createTimer(callback, milliSeconds, true);
-  }
-
-  _Timer._internal() {}
-
-  void _clear() {
-    _callback = null;
-    _milliSeconds = 0;
-    _wakeupTime = 0;
-    _repeating = false;
-  }
-
-
-  // Cancels a set timer. The timer is removed from the timer list and if
-  // the given timer is the earliest timer the native timer is reset.
-  void cancel() {
-    _clear();
-    DoubleLinkedQueueEntry<_Timer> entry = _timers.firstEntry();
-    DoubleLinkedQueueEntry<_Timer> first = _timers.firstEntry();
-
-     while (entry !== null) {
-      if (entry.element === this) {
-        entry.remove();
-        if (first.element == this) {
-          entry = _timers.firstEntry();
-          _notifyEventHandler();
-        }
-        return;
-      }
-      entry = entry.nextEntry();
-    }
-  }
-
-  void _advanceWakeupTime() {
-    _wakeupTime += _milliSeconds;
-  }
-
-  // Adds a timer to the timer list and resets the native timer if it is the
-  // earliest timer in the list.  Timers with the same wakeup time are enqueued
-  // in order and notified in FIFO order.
-  void _addTimerToList() {
-    if (_callback !== null) {
-
-      DoubleLinkedQueueEntry<_Timer> entry = _timers.firstEntry();
-      while (entry !== null) {
-        if (_wakeupTime < entry.element._wakeupTime) {
-          entry.prepend(this);
-          return;
-        }
-        entry = entry.nextEntry();
-      }
-      _timers.addLast(this);
-    }
-  }
-
-
-  void _notifyEventHandler() {
-    if (_handling_callbacks) {
-      // While we are already handling callbacks we will not notify the event
-      // handler. _handleTimeout will call _notifyEventHandler once all pending
-      // timers are processed.
-      return;
-    }
-
-    if (_timers.firstEntry() === null) {
-      // No pending timers: Close the receive port and let the event handler
-      // know.
-      if (_receivePort !== null) {
-        _EventHandler._sendData(null, _receivePort, _NO_TIMER);
-        _shutdownTimerHandler();
-      }
-    } else {
-      if (_receivePort === null) {
-        // Create a receive port and register a message handler for the timer
-        // events.
-        _createTimerHandler();
-      }
-      _EventHandler._sendData(null,
-                              _receivePort,
-                              _timers.firstEntry().element._wakeupTime);
-    }
-  }
-
-
-  // Creates a receive port and registers the timer handler on that
-  // receive port.
-  void _createTimerHandler() {
-
-    void _handleTimeout() {
-      int currentTime =
-          (new Date.now()).millisecondsSinceEpoch + _TIMER_JITTER;
-
-      // Collect all pending timers.
-      DoubleLinkedQueueEntry<_Timer> entry = _timers.firstEntry();
-      var pending_timers = new List();
-      while (entry !== null) {
-        _Timer timer = entry.element;
-        if (timer._wakeupTime <= currentTime) {
-          entry.remove();
-          pending_timers.addLast(timer);
-          entry = _timers.firstEntry();
-        } else {
-          break;
-        }
-      }
-
-      // Trigger all of the pending timers. New timers added as part of the
-      // callbacks will be enqueued now and notified in the next spin at the
-      // earliest.
-      _handling_callbacks = true;
-      try {
-        for (var timer in pending_timers) {
-          // One of the timers in the pending_timers list can cancel
-          // one of the later timers which will set the callback to
-          // null.
-          if (timer._callback != null) {
-            timer._callback(timer);
-            if (timer._repeating) {
-              timer._advanceWakeupTime();
-              timer._addTimerToList();
-            }
-          }
-        }
-      } finally {
-        _handling_callbacks = false;
-      }
-      _notifyEventHandler();
-    }
-
-    if(_receivePort === null) {
-      _receivePort = new ReceivePort();
-      _receivePort.receive((var message, ignored) {
-        _handleTimeout();
-      });
-    }
-  }
-
-  void _shutdownTimerHandler() {
-    _receivePort.close();
-    _receivePort = null;
-  }
-
-
-  // Timers are ordered by wakeup time.
-  static DoubleLinkedQueue<_Timer> _timers;
-
-  static ReceivePort _receivePort;
-  static bool _handling_callbacks = false;
-
-  var _callback;
-  int _milliSeconds;
-  int _wakeupTime;
-  bool _repeating;
-}
-
-// Provide a closure which will allocate a Timer object to be able to hook
-// up the Timer interface in dart:isolate with the implementation here.
-_getTimerFactoryClosure() {
-  return (int milliSeconds, void callback(Timer timer), bool repeating) {
-    if (repeating) {
-      return new _Timer.repeating(milliSeconds, callback);
-    }
-    return new _Timer(milliSeconds, callback);
-  };
-}
-
-