static bool WaitInternal(int?msTimeout, Func <bool> condition)
{
bool timedOut = false;
Debug.Assert(SynchronizationContext.Current is DispatcherSynchronizationContext);
DispatcherFrame frame = new DispatcherFrame();
DispatcherHookEventHandler onOperationCompleted = null;
Action popFrame = () => {
frame.Continue = false;
Dispatcher.CurrentDispatcher.Hooks.OperationCompleted -= onOperationCompleted;
};
onOperationCompleted = (s, ea) => {
if (condition())
{
popFrame();
}
};
Dispatcher.CurrentDispatcher.BeginInvoke(new Action(() => {
Dispatcher.CurrentDispatcher.Hooks.OperationCompleted += onOperationCompleted;
}));
if (msTimeout != null)
{
PumpTimer.DoLater(msTimeout.Value, () => {
timedOut = true;
popFrame();
});
}
Dispatcher.PushFrame(frame);
return(!timedOut);
}
internal void EmitOperationPriorityChanged(DispatcherOperation op)
{
DispatcherHookEventHandler prio = this.OperationPriorityChanged;
if (prio != null)
{
prio(this.owner, new DispatcherHookEventArgs(op));
}
}
internal void EmitOperationAborted(DispatcherOperation op)
{
DispatcherHookEventHandler aborted = this.OperationAborted;
if (aborted != null)
{
aborted(this.owner, new DispatcherHookEventArgs(op));
}
}
internal void EmitOperationCompleted(DispatcherOperation op)
{
DispatcherHookEventHandler completed = this.OperationCompleted;
if (completed != null)
{
completed(this.owner, new DispatcherHookEventArgs(op));
}
}
internal void RaiseOperationAborted(Dispatcher dispatcher, DispatcherOperation operation)
{
DispatcherHookEventHandler operationAborted = _operationAborted;
if (operationAborted != null)
{
operationAborted(dispatcher, new DispatcherHookEventArgs(operation));
}
}
internal void EmitOperationPosted(DispatcherOperation op)
{
DispatcherHookEventHandler posted = OperationPosted;
if (posted != null)
{
posted(owner, new DispatcherHookEventArgs(op));
}
}
private void Watchdog()
{
while (!_shuttingDown)
{
_idleReached = false;
Thread.Sleep(MaxBusy);
if (!_idleReached && !Debugger.IsAttached)
{
//Make sure we don't see our own post monitoring!
//TODO: should we sample more than once?
#pragma warning disable 612,618
var thread = _dispatcher.Thread;
thread.Suspend();
var timedOutTrace = new StackTrace(thread, false);
thread.Resume();
#pragma warning restore 612,618
var postedOperations = new BlockingCollection <DispatcherOperation>();
DispatcherHookEventHandler hooksOnOperationPosted = null;
const int maxOperationToLog = 100;
hooksOnOperationPosted = delegate(object sender, DispatcherHookEventArgs e)
{
if (postedOperations.Count < maxOperationToLog)
{
postedOperations.Add(e.Operation);
}
else
{
_dispatcher.Hooks.OperationPosted -= hooksOnOperationPosted;
}
};
_dispatcher.Hooks.OperationPosted += hooksOnOperationPosted;
var sb = new StringBuilder();
sb.AppendLine("Dispatcher is blocked:");
sb.AppendLine(timedOutTrace.ToString());
Thread.Sleep(SamplePeriod); //wait for some posts
var nameGetter = typeof(DispatcherOperation).GetProperty("Name", BindingFlags.Default | BindingFlags.NonPublic | BindingFlags.Instance).GetGetMethod(true);
foreach (var operation in postedOperations)
{
sb.AppendLine(nameGetter.Invoke(operation, new object[] { }).ToString());
}
var message = sb.ToString();
Logger.Error(message);
throw new OpenGammaException(message); //Should be caught by general error handler
}
}
}
public static bool WaitOneAndPump(this WaitHandle handle, int millisecondsTimeout)
{
using (var operationPendingMre = new ManualResetEvent(false))
{
bool result = false;
Exception error = null;
var startTick = Environment.TickCount;
var handles = new[] {
handle.SafeWaitHandle.DangerousGetHandle(),
operationPendingMre.SafeWaitHandle.DangerousGetHandle()
};
var dispatcher = Dispatcher.CurrentDispatcher;
var frame = new DispatcherFrame();
var getTimeout = (Timeout.Infinite == millisecondsTimeout) ?
new Func <uint>(() => INFINITE) :
new Func <uint>(() => (uint)Math.Max(0,
millisecondsTimeout + startTick - Environment.TickCount));
DispatcherHookEventHandler onOperationPosted = (s, e) =>
{
// this may occur on a random thread,
// trigger a helper event and
// unblock MsgWaitForMultipleObjectsEx inside onDispatcherInactive
operationPendingMre.Set();
};
DispatcherHookEventHandler onOperationCompleted = (s, e) =>
{
// this should occur on the Dispather thread
Debug.Assert(Thread.CurrentThread == dispatcher.Thread);
// do an instant handle check
var nativeResult = WaitForSingleObject(handles[0], 0);
if (nativeResult == WAIT_OBJECT_0)
{
result = true;
}
else if (nativeResult == WAIT_ABANDONED_0)
{
error = new AbandonedMutexException(-1, handle);
}
else if (getTimeout() == 0)
{
result = false;
}
else if (nativeResult == WAIT_TIMEOUT)
{
return;
}
else
{
error = new InvalidOperationException("WaitForSingleObject");
}
// end the nested Dispatcher loop
frame.Continue = false;
};
EventHandler onDispatcherInactive = (s, e) =>
{
operationPendingMre.Reset();
// wait for the handle or a message
var timeout = getTimeout();
var nativeResult = MsgWaitForMultipleObjectsEx(
(uint)handles.Length, handles,
timeout,
QS_EVENTMASK,
MWMO_INPUTAVAILABLE);
if (nativeResult == WAIT_OBJECT_0)
{
result = true; // handle signalled
}
else if (nativeResult == WAIT_TIMEOUT)
{
result = false; // timed-out
}
else if (nativeResult == WAIT_ABANDONED_0)
{
error = new AbandonedMutexException(-1, handle);
}
else if (nativeResult != WAIT_OBJECT_0 + 1 && nativeResult != WAIT_OBJECT_0 + 2)
{
error = new InvalidOperationException("MsgWaitForMultipleObjectsEx");
}
else
{
// a Windows message or a Dispatcher operation is pending
if (timeout == 0)
{
result = false; // timed-out
}
else
{
return;
}
}
// end the nested Dispatcher loop
frame.Continue = false;
};
dispatcher.Hooks.OperationCompleted += onOperationCompleted;
dispatcher.Hooks.OperationPosted += onOperationPosted;
dispatcher.Hooks.DispatcherInactive += onDispatcherInactive;
try
{
// onDispatcherInactive will be called on the new frame,
// as soon as Dispatcher becomes idle
Dispatcher.PushFrame(frame);
}
finally
{
dispatcher.Hooks.OperationCompleted -= onOperationCompleted;
dispatcher.Hooks.OperationPosted -= onOperationPosted;
dispatcher.Hooks.DispatcherInactive -= onDispatcherInactive;
}
if (error != null)
{
throw error;
}
return(result);
}
}
public static bool WaitOneAndPump(this WaitHandle handle, int millisecondsTimeout)
{
using (var operationPendingMre = new ManualResetEvent(false))
{
var result = false;
var startTick = Environment.TickCount;
var dispatcher = Dispatcher.CurrentDispatcher;
var frame = new DispatcherFrame();
var handles = new[] {
handle.SafeWaitHandle.DangerousGetHandle(),
operationPendingMre.SafeWaitHandle.DangerousGetHandle()
};
Action idleAction = () => operationPendingMre.Set();
DispatcherOperation idleOperation = null;
Func <uint> getTimeout;
if (Timeout.Infinite == millisecondsTimeout)
{
getTimeout = () => INFINITE;
}
else
{
getTimeout = () => (uint)Math.Max(0, millisecondsTimeout + startTick - Environment.TickCount);
}
DispatcherHookEventHandler onOperationPosted = (s, e) =>
{
// this may occur on a random thread,
// trigger a helper event and
// unblock MsgWaitForMultipleObjectsEx inside onDispatcherInactive
operationPendingMre.Set();
};
DispatcherHookEventHandler onOperationCompleted = (s, e) =>
{
// this should be fired on the Dispather thread
Debug.Assert(Thread.CurrentThread == dispatcher.Thread);
// do an instant handle check
var nativeResult = WaitForSingleObject(handles[0], 0);
if (nativeResult == WAIT_OBJECT_0)
{
result = true;
}
else if (nativeResult == WAIT_ABANDONED_0)
{
throw new AbandonedMutexException(-1, handle);
}
else if (getTimeout() == 0)
{
result = false;
}
else if (nativeResult == WAIT_TIMEOUT)
{
return;
}
else
{
throw new InvalidOperationException("WaitForSingleObject");
}
// end the nested Dispatcher loop
frame.Continue = false;
};
EventHandler onDispatcherInactive = (s, e) =>
{
operationPendingMre.Reset();
// wait for the handle or a message
var timeout = getTimeout();
var nativeResult = MsgWaitForMultipleObjectsEx(
(uint)handles.Length, handles,
timeout,
QS_EVENTMASK,
MWMO_INPUTAVAILABLE);
if (nativeResult == WAIT_OBJECT_0)
{
// handle signalled
result = true;
}
else if (nativeResult == WAIT_TIMEOUT)
{
// timed out
result = false;
}
else if (nativeResult == WAIT_ABANDONED_0)
{
// abandonded mutex
throw new AbandonedMutexException(-1, handle);
}
else if (nativeResult == WAIT_OBJECT_0 + 1)
{
// operation posted from another thread, yield to the frame loop
return;
}
else if (nativeResult == WAIT_OBJECT_0 + 2)
{
// a Windows message
if (getTimeout() > 0)
{
// message pending, yield to the frame loop
idleOperation.Abort();
idleOperation = dispatcher.BeginInvoke(idleAction, DispatcherPriority.ApplicationIdle);
return;
}
// timed out
result = false;
}
else
{
// unknown result
throw new InvalidOperationException("MsgWaitForMultipleObjectsEx");
}
// end the nested Dispatcher loop
frame.Continue = false;
};
dispatcher.Hooks.OperationCompleted += onOperationCompleted;
dispatcher.Hooks.OperationPosted += onOperationPosted;
dispatcher.Hooks.DispatcherInactive += onDispatcherInactive;
idleOperation = dispatcher.BeginInvoke(idleAction, DispatcherPriority.ApplicationIdle);
try
{
// onDispatcherInactive will be called on the new frame,
// as soon as Dispatcher becomes idle
Dispatcher.PushFrame(frame);
}
finally
{
idleOperation.Abort();
dispatcher.Hooks.OperationCompleted -= onOperationCompleted;
dispatcher.Hooks.OperationPosted -= onOperationPosted;
dispatcher.Hooks.DispatcherInactive -= onDispatcherInactive;
}
return(result);
}
}
