protected virtual void GetMetadata(out Guid eventSourceGuid, out string eventSourceName, out EventDescriptor[] eventDescriptors, out byte[] manifestBytes)
{
//
// Subclasses need to override this method, and return the data from their EventSourceAttribute and EventAttribute annotations.
//
// eventDescriptors needs to contain one EventDescriptor for each event; the event's ID should be the same as its index in this array.
// manifestBytes is a UTF-8 encoding of the ETW manifest for the type.
//
// This will be implemented by an IL rewriter, so we can't make this method abstract or the initial build of the subclass would fail.
//
throw new InvalidOperationException(SR.EventSource_ImplementGetMetadata);
}
public bool Equals(EventDescriptor other)
{
if ((m_id != other.m_id) ||
(m_version != other.m_version) ||
(m_channel != other.m_channel) ||
(m_level != other.m_level) ||
(m_opcode != other.m_opcode) ||
(m_task != other.m_task) ||
(m_keywords != other.m_keywords))
{
return false;
}
return true;
}
internal unsafe bool WriteEvent(ref EventDescriptor eventDescriptor, Guid* childActivityID, params object[] eventPayload)
{
int status = 0;
if (IsEnabled(eventDescriptor.Level, eventDescriptor.Keywords))
{
int argCount = 0;
unsafe
{
argCount = eventPayload.Length;
if (argCount > s_etwMaxMumberArguments)
{
s_returnCode = WriteEventErrorCode.TooManyArgs;
return false;
}
uint totalEventSize = 0;
int index;
int stringIndex = 0;
List<int> stringPosition = new List<int>(s_etwAPIMaxStringCount);
List<string> dataString = new List<string>(s_etwAPIMaxStringCount);
EventData* userData = stackalloc EventData[argCount];
EventData* userDataPtr = (EventData*)userData;
byte* dataBuffer = stackalloc byte[s_basicTypeAllocationBufferSize * argCount]; // Assume 16 chars for non-string argument
byte* currentBuffer = dataBuffer;
//
// The loop below goes through all the arguments and fills in the data
// descriptors. For strings save the location in the dataString array.
// Calculates the total size of the event by adding the data descriptor
// size value set in EncodeObject method.
//
for (index = 0; index < eventPayload.Length; index++)
{
if (eventPayload[index] != null)
{
string isString;
isString = EncodeObject(ref eventPayload[index], userDataPtr, currentBuffer);
currentBuffer += s_basicTypeAllocationBufferSize;
totalEventSize += userDataPtr->Size;
userDataPtr++;
if (isString != null)
{
dataString.Add(isString);
stringPosition.Add(index);
stringIndex++;
}
}
else
{
s_returnCode = WriteEventErrorCode.NullInput;
return false;
}
}
if (totalEventSize > s_traceEventMaximumSize)
{
s_returnCode = WriteEventErrorCode.EventTooBig;
return false;
}
if (stringIndex < s_etwAPIMaxStringCount)
{
// Fast path: at most 8 string arguments
// ensure we have at least s_etwAPIMaxStringCount in dataString, so that
// the "fixed" statement below works
while (stringIndex < s_etwAPIMaxStringCount)
{
dataString.Add(null);
++stringIndex;
}
//
// now fix any string arguments and set the pointer on the data descriptor
//
fixed (char* v0 = dataString[0], v1 = dataString[1], v2 = dataString[2], v3 = dataString[3],
v4 = dataString[4], v5 = dataString[5], v6 = dataString[6], v7 = dataString[7])
{
userDataPtr = (EventData*)userData;
if (dataString[0] != null)
{
userDataPtr[stringPosition[0]].Ptr = (ulong)v0;
}
if (dataString[1] != null)
{
userDataPtr[stringPosition[1]].Ptr = (ulong)v1;
}
if (dataString[2] != null)
{
userDataPtr[stringPosition[2]].Ptr = (ulong)v2;
}
if (dataString[3] != null)
{
userDataPtr[stringPosition[3]].Ptr = (ulong)v3;
}
if (dataString[4] != null)
{
userDataPtr[stringPosition[4]].Ptr = (ulong)v4;
}
if (dataString[5] != null)
{
userDataPtr[stringPosition[5]].Ptr = (ulong)v5;
}
if (dataString[6] != null)
{
userDataPtr[stringPosition[6]].Ptr = (ulong)v6;
}
if (dataString[7] != null)
{
userDataPtr[stringPosition[7]].Ptr = (ulong)v7;
}
if (childActivityID == null)
status = UnsafeNativeMethods.ManifestEtw.EventWrite(m_regHandle, ref eventDescriptor, argCount, userData);
else
status = UnsafeNativeMethods.ManifestEtw.EventWriteTransfer(m_regHandle, ref eventDescriptor, null, childActivityID, argCount, userData);
}
}
else
{
// Slow path: use pinned handles
userDataPtr = (EventData*)userData;
GCHandle[] rgGCHandle = new GCHandle[stringIndex];
for (int i = 0; i < stringIndex; ++i)
{
rgGCHandle[i] = GCHandle.Alloc(dataString[i], GCHandleType.Pinned);
fixed (char* p = dataString[i])
userDataPtr[stringPosition[i]].Ptr = (ulong)p;
}
if (childActivityID == null)
status = UnsafeNativeMethods.ManifestEtw.EventWrite(m_regHandle, ref eventDescriptor, argCount, userData);
else
status = UnsafeNativeMethods.ManifestEtw.EventWriteTransfer(m_regHandle, ref eventDescriptor, null, childActivityID, argCount, userData);
for (int i = 0; i < stringIndex; ++i)
{
rgGCHandle[i].Free();
}
}
}
}
if (status != 0)
{
SetLastError((int)status);
return false;
}
return true;
}
internal unsafe protected bool WriteEvent(ref EventDescriptor eventDescriptor, Guid* childActivityID, int dataCount, IntPtr data)
{
int status;
if (childActivityID == null)
{
status = UnsafeNativeMethods.ManifestEtw.EventWrite(m_regHandle, ref eventDescriptor, dataCount, (EventData*)data);
}
else
{
// activity transfers are supported only for events that specify the Send or Receive opcode
Contract.Assert((EventOpcode)eventDescriptor.Opcode == EventOpcode.Send ||
(EventOpcode)eventDescriptor.Opcode == EventOpcode.Receive);
status = UnsafeNativeMethods.ManifestEtw.EventWriteTransfer(m_regHandle, ref eventDescriptor, null, childActivityID, dataCount, (EventData*)data);
}
if (status != 0)
{
SetLastError(status);
return false;
}
return true;
}
public EventMetadata(EventDescriptor descriptor,
EventTags tags,
bool enabledForAnyListener,
bool enabledForETW,
string name,
string message,
EventParameterType[] parameterTypes)
{
this.Descriptor = descriptor;
this.Tags = tags;
this.EnabledForAnyListener = enabledForAnyListener;
this.EnabledForETW = enabledForETW;
this.TriggersActivityTracking = 0;
this.Name = name;
this.Message = message;
this.Parameters = null;
this.TraceLoggingEventTypes = null;
this.ActivityOptions = EventActivityOptions.None;
this.ParameterTypes = parameterTypes;
this.HasRelatedActivityID = false;
}
/// <summary>
/// Call the ETW native API EventWriteTransfer and checks for invalid argument error.
/// The implementation of EventWriteTransfer on some older OSes (Windows 2008) does not accept null relatedActivityId.
/// So, for these cases we will retry the call with an empty Guid.
/// </summary>
internal static int EventWriteTransferWrapper(long registrationHandle,
ref EventDescriptor eventDescriptor,
Guid* activityId,
Guid* relatedActivityId,
int userDataCount,
EventProvider.EventData* userData)
{
int HResult = EventWriteTransfer(registrationHandle, ref eventDescriptor, activityId, relatedActivityId, userDataCount, userData);
if (HResult == ERROR_INVALID_PARAMETER && relatedActivityId == null)
{
Guid emptyGuid = Guid.Empty;
HResult = EventWriteTransfer(registrationHandle, ref eventDescriptor, activityId, &emptyGuid, userDataCount, userData);
}
return HResult;
}