Update Dart bindings to support updated MojoWait and MojoWaitMany APIs.

mojo/public/dart/src/handle_watcher.dart

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 part of core;
 
 class _MojoHandleWatcherNatives {
   static int sendControlData(
       int controlHandle, int mojoHandle, SendPort port, int data)
       native "MojoHandleWatcher_SendControlData";
@@ skipping 81 matching lines @@
     _handles.add(_controlHandle);
     _ports.add(null);  // There is no port for the control handle.
     _signals.add(MojoHandleSignals.READABLE);
     _handleIndices[_controlHandle] = 0;
   }
 
   static void _handleWatcherIsolate(int consumerHandle) {
     MojoHandleWatcher watcher = new MojoHandleWatcher(consumerHandle);
     while (!watcher._shutdown) {
       int deadline = watcher._processTimerDeadlines();
-      int res = RawMojoHandle.waitMany(watcher._handles,
+      MojoWaitManyResult res = RawMojoHandle.waitMany(watcher._handles,
                                        watcher._signals,
                                        deadline);
-      if (res == 0) {
+      if (res.result.isOk && res.index == 0) {
         watcher._handleControlMessage();
-      } else if (res > 0) {
-        int handle = watcher._handles[res];
+      } else if (res.result.isOk && res.index > 0) {
+        int handle = watcher._handles[res.index];
         // Route event.
-        watcher._routeEvent(res);
+        watcher._routeEvent(res.index);
         // Remove the handle from the list.
         watcher._removeHandle(handle);
-      } else if (res != MojoResult.kDeadlineExceeded) {
+      } else if (res.areSignalStatesValid) {
         // Some handle was closed, but not by us.
-        // We have to go through the list and find it.
-        watcher._pruneClosedHandles();
+        // Find it and close it on our side.
+        watcher._pruneClosedHandles(res.states);
       }
     }
   }
 
   void _routeEvent(int idx) {
     int client_handle = _handles[idx];
     int signals = _signals[idx];
     SendPort port = _ports[idx];
 
     _tempHandle.h = client_handle;
@@ skipping 121 matching lines @@
     if (idx == null) {
       throw new Exception(
           "Toggle write on a non-existent handle: $mojoHandle.");
     }
     if (idx == 0) {
       throw new Exception("The control handle (idx = 0) cannot be toggled.");
     }
     _signals[idx] = MojoHandleSignals.toggleWrite(_signals[idx]);
   }
 
-  void _pruneClosedHandles() {
+  void _pruneClosedHandles(List<MojoHandleSignalsState> states) {
     List<int> closed = new List();
-    for (var h in _handles) {
-      _tempHandle.h = h;
-      MojoResult res = _tempHandle.wait(MojoHandleSignals.READWRITE, 0);
-      if ((!res.isOk) && (!res.isDeadlineExceeded)) {
-        closed.add(h);
+    for (var i=0; i<_handles.length; i++) {
+      if (MojoHandleSignals.isPeerClosed(states[i].satisfied_signals)) {
+        closed.add(_handles[i]);
       }
-      _tempHandle.h = RawMojoHandle.INVALID;
     }
     for (var h in closed) {
-      _close(h, pruning: true);
+      _close(h, pruning: true);  
     }
+    // _close updated the _handles array, so at this point the _handles array
+    // and the signals array are mismatched.

[zra, 2015/01/08 17:23:11]

This is not correct. _close() calls _removeHandle(), which keeps everything
consistent.

[jimbe, 2015/01/08 17:38:21]

Poor choice of words. There are two separate signals arrays, the second of which
is passed into this function. Fixed wording.

   }
 
   void _shutdownHandleWatcher() {
     _shutdown = true;
     _tempHandle.h = _controlHandle;
     _tempHandle.close();
     _tempHandle.h = RawMojoHandle.INVALID;
   }
 
   static MojoResult _sendControlData(RawMojoHandle mojoHandle,
@@ skipping 54 matching lines @@
   static MojoResult remove(RawMojoHandle mojoHandle) {
     return _sendControlData(mojoHandle, null, _encodeCommand(REMOVE));
   }
 
   static MojoResult timer(SendPort port, int deadline) {
     // The deadline will be unwrapped before sending to the handle watcher.
     return _sendControlData(
         new RawMojoHandle(deadline), port, _encodeCommand(TIMER));
   }
 }