private void OpenEtwEventCacheFile(object context)
{
ReadEventsFromFileParam param = (ReadEventsFromFileParam)context;
param.FileNotFound = false;
try
{
FileStream fileStream = FabricFile.Open(param.FileName, FileMode.Open, FileAccess.Read);
#if !DotNetCoreClr
Helpers.SetIoPriorityHint(fileStream.SafeFileHandle, Kernel32Types.PRIORITY_HINT.IoPriorityHintVeryLow);
#endif
param.StreamReader = new StreamReader(fileStream);
}
catch (FileNotFoundException e)
{
// The file was not found, most likely because it was deleted by
// the old logs deletion routine.
this.TraceSource.WriteWarning(
this.LogSourceId,
"Exception occurred while trying to open buffered event file {0} for read. The file may have been deleted. Exception information: {1}",
param.FileName,
e);
param.FileNotFound = true;
}
}
private void ProcessEventsFromFile(string fileName)
{
this.TraceSource.WriteInfo(
this.LogSourceId,
"Processing ETW events from file {0}.",
fileName);
// Open the file
ReadEventsFromFileParam readEventsParam = new ReadEventsFromFileParam();
readEventsParam.StreamReader = null;
readEventsParam.FileName = fileName;
try
{
Utility.PerformIOWithRetries(
this.OpenEtwEventCacheFile,
readEventsParam);
}
catch (Exception e)
{
this.TraceSource.WriteExceptionAsError(
this.LogSourceId,
e,
"Failed to open file {0} for read.",
fileName);
return;
}
if (readEventsParam.FileNotFound)
{
Debug.Assert(null == readEventsParam.StreamReader, "StreamReader should remain unset if file is not found.");
return;
}
// Read and process events from the file
try
{
// Check the DCA version to make sure we can parse this file
int version;
if (false == this.CanParseFile(readEventsParam.StreamReader, fileName, out version))
{
return;
}
// Upload the ETW events that we just retrieved
this.TraceSource.WriteInfo(
this.LogSourceId,
"Starting delivery of ETW events from file {0} ....",
fileName);
LineParam lineParam = new LineParam();
lineParam.Reader = readEventsParam.StreamReader;
for (;;)
{
// Read an event from the file
try
{
ReadLineFromFile(lineParam);
}
catch (Exception e)
{
this.TraceSource.WriteExceptionAsError(
this.LogSourceId,
e,
"Failed to read event from file {0}.",
fileName);
break;
}
if (null == lineParam.Line)
{
// End of file reached
break;
}
DecodedEtwEvent etwEventInfo = new DecodedEtwEvent();
string nodeUniqueEventId = null;
if (false == this.ParseEventInfo(fileName, version, lineParam.Line, ref etwEventInfo, ref nodeUniqueEventId))
{
// Couldn't parse this event, so skip it and continue with the
// remaining events.
continue;
}
// Deliver the event to the consumer
this.eventSink.OnEtwEventAvailable(etwEventInfo, nodeUniqueEventId);
this.perfHelper.EventDeliveredToConsumer();
// If the consumer has asked for the event delivery period to
// be aborted, then do so immediately.
if (this.eventDeliveryPeriodAborted)
{
this.TraceSource.WriteInfo(
this.LogSourceId,
"The event delivery pass is being aborted. Therefore, no more events will be read from file {0}.",
fileName);
break;
}
// If we are in the process of stopping, then don't process
// any more events
if (this.Stopping)
{
this.TraceSource.WriteInfo(
this.LogSourceId,
"The consumer is being stopped. Therefore, no more events will be read from file {0}.",
fileName);
break;
}
}
this.TraceSource.WriteInfo(
this.LogSourceId,
"Finished delivery of ETW events from file {0}.",
fileName);
}
finally
{
readEventsParam.StreamReader.Dispose();
}
}
