private async Task EventLogPollingTaskAsync(int waitMillis)
{
try
{
LogHelper.Info($"Start security event log polling ...");
DateTime lastLogEntryTimeStamp = DateTime.Now;
CancellationToken cancellationToken = _eventLogPollingTaskCancellationTokenSource.Token;
while (true)
{
try
{
using (EventLog securityLog = new EventLog("security"))
{
List <EventLogEntry> newEntryList = new List <EventLogEntry>();
int entryIndex = securityLog.Entries.Count - 1;
DateTime newestEntryTimeWritten = securityLog.Entries[entryIndex].TimeWritten;
for (int i = entryIndex; i >= 0; i--)
{
CheckCancelTaskRequestedAndThrow(cancellationToken);
EventLogEntry entry = securityLog.Entries[i];
bool isNewEntry = entry.TimeWritten > lastLogEntryTimeStamp;
if (isNewEntry)
{
if (IsEventInstanceIdAccepted(entry.InstanceId))
{
WPFUtils.DispatchUI(() => App.GetActivityWindow().ShowActivity(ActivityWindow.ActivityEnum.Blocked));
newEntryList.Insert(0, entry);
}
else
{
WPFUtils.DispatchUI(() => App.GetActivityWindow().ShowActivity(ActivityWindow.ActivityEnum.Allowed));
}
}
else
{
break;
}
}
lastLogEntryTimeStamp = newestEntryTimeWritten;
foreach (EventLogEntry entry in newEntryList)
{
CheckCancelTaskRequestedAndThrow(cancellationToken);
Application.Current.Dispatcher.Invoke(() =>
{
// dispatch to ui thread
_application.HandleEventLogNotification(entry);
});
}
}
}
catch (ArgumentException e)
{
LogHelper.Warning($"Security log entry does not exist anymore:" + e.Message);
}
CheckCancelTaskRequestedAndThrow(cancellationToken);
await Task.Delay(waitMillis, cancellationToken).ConfigureAwait(false);
}
}
catch (SecurityException se)
{
LogHelper.Error($"Notifier cannot access security event log: { se.Message}. Notifier needs to be started with admin rights and will exit now", se);
MessageBox.Show($"Notifier cannot access security event log:\n{se.Message}\nNotifier needs to be started with admin rights.\nNotifier will exit.", "Error", MessageBoxButton.OK, MessageBoxImage.Error);
this._application.Shutdown();
}
catch (Exception e)
{
LogHelper.Error("EventLogPollingTaskAsync exception: " + e.Message, e);
MessageBox.Show($"Security event log polling exception:\n{e.Message}\nNotifier will exit", "Error", MessageBoxButton.OK, MessageBoxImage.Warning);
this._application.Shutdown();
}
}
