unsafe void Initialize(Guid guid)
{
controlGuid = guid;
TraceGuidRegistration guidReg = new TraceGuidRegistration();
Guid dummyGuid = new Guid("{aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaabbb}");
etwProc = new EtwTraceCallback(EtwNotificationCallback);
guidReg.Guid = &dummyGuid;
guidReg.RegHandle = null;
uint status = EtwNativeMethods.RegisterTraceGuids(etwProc,
null,
ref controlGuid,
1,
ref guidReg,
null,
null,
out registrationHandle);
if (status != 0)
{
throw new Win32Exception((int)status);
}
this.isDisposed = false;
}
public void Dispose(bool disposing)
{
if (disposing)
{
int result = EtwNativeMethods.UnregisterTraceGuids(this.registrationHandle);
// PreSharp requires this: ignore result as we can neither trace nor throw
}
this.isDisposed = true;
}
internal unsafe uint Trace(MofEvent *evt)
{
bool shouldRedispose = this.isDisposed;
if (shouldRedispose)
{
this.Initialize(this.controlGuid);
}
uint retval = EtwNativeMethods.TraceEvent(traceHandle, (char *)evt);
if (shouldRedispose)
{
this.Dispose(true);
}
return(retval);
}
unsafe uint EtwNotificationCallback(uint requestCode, System.IntPtr context, System.IntPtr bufferSize, byte *buffer)
{
if (null == buffer)
{
//note that the return value will be ignored
return(uint.MaxValue);
}
EventTraceHeader *eventBuffer = (EventTraceHeader *)buffer;
switch (requestCode)
{
case RequestCodes.EnableEvents:
this.traceHandle = eventBuffer->HistoricalContext;
int flags = EtwNativeMethods.GetTraceEnableFlags((ulong)this.traceHandle);
int level = EtwNativeMethods.GetTraceEnableLevel((ulong)this.traceHandle);
using (Process process = Process.GetCurrentProcess())
{
if (flags == process.Id)
{
//TODO, vadim, if the listener is private, forward the level
//if not, consider using TraceFilter
//Level = LevelFromInt(level);
}
}
break;
case RequestCodes.DisableEvents:
this.traceHandle = 0;
break;
default:
this.traceHandle = 0;
break;
}
return(0);
}