private DynamicTraceEventData.PayloadFetchClassInfo ParseFields(PinnedStreamReader reader, int numFields)
{
string[] fieldNames = new string[numFields];
DynamicTraceEventData.PayloadFetch[] fieldFetches = new DynamicTraceEventData.PayloadFetch[numFields];
ushort offset = 0;
for (int fieldIndex = 0; fieldIndex < numFields; fieldIndex++)
{
DynamicTraceEventData.PayloadFetch payloadFetch = new DynamicTraceEventData.PayloadFetch();
// Read the TypeCode for the current field.
TypeCode typeCode = (TypeCode)reader.ReadInt32();
// Fill out the payload fetch object based on the TypeCode.
switch (typeCode)
{
case TypeCode.Boolean:
{
payloadFetch.Type = typeof(bool);
payloadFetch.Size = 4; // We follow windows conventions and use 4 bytes for bool.
payloadFetch.Offset = offset;
break;
}
case TypeCode.Char:
{
payloadFetch.Type = typeof(char);
payloadFetch.Size = sizeof(char);
payloadFetch.Offset = offset;
break;
}
case TypeCode.SByte:
{
payloadFetch.Type = typeof(SByte);
payloadFetch.Size = sizeof(SByte);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Byte:
{
payloadFetch.Type = typeof(byte);
payloadFetch.Size = sizeof(byte);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Int16:
{
payloadFetch.Type = typeof(Int16);
payloadFetch.Size = sizeof(Int16);
payloadFetch.Offset = offset;
break;
}
case TypeCode.UInt16:
{
payloadFetch.Type = typeof(UInt16);
payloadFetch.Size = sizeof(UInt16);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Int32:
{
payloadFetch.Type = typeof(Int32);
payloadFetch.Size = sizeof(Int32);
payloadFetch.Offset = offset;
break;
}
case TypeCode.UInt32:
{
payloadFetch.Type = typeof(UInt32);
payloadFetch.Size = sizeof(UInt32);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Int64:
{
payloadFetch.Type = typeof(Int64);
payloadFetch.Size = sizeof(Int64);
payloadFetch.Offset = offset;
break;
}
case TypeCode.UInt64:
{
payloadFetch.Type = typeof(UInt64);
payloadFetch.Size = sizeof(UInt64);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Single:
{
payloadFetch.Type = typeof(Single);
payloadFetch.Size = sizeof(Single);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Double:
{
payloadFetch.Type = typeof(Double);
payloadFetch.Size = sizeof(Double);
payloadFetch.Offset = offset;
break;
}
case TypeCode.Decimal:
{
payloadFetch.Type = typeof(Decimal);
payloadFetch.Size = sizeof(Decimal);
payloadFetch.Offset = offset;
break;
}
case TypeCode.DateTime:
{
payloadFetch.Type = typeof(DateTime);
payloadFetch.Size = 8;
payloadFetch.Offset = offset;
break;
}
case EventPipeEventSource.GuidTypeCode:
{
payloadFetch.Type = typeof(Guid);
payloadFetch.Size = 16;
payloadFetch.Offset = offset;
break;
}
case TypeCode.String:
{
payloadFetch.Type = typeof(String);
payloadFetch.Size = DynamicTraceEventData.NULL_TERMINATED;
payloadFetch.Offset = offset;
break;
}
case TypeCode.Object:
{
// TypeCode.Object represents an embedded struct.
// Read the number of fields in the struct. Each of these fields could be an embedded struct,
// but these embedded structs are still counted as single fields. They will be expanded when they are handled.
int structFieldCount = reader.ReadInt32();
DynamicTraceEventData.PayloadFetchClassInfo embeddedStructClassInfo = ParseFields(reader, structFieldCount);
if (embeddedStructClassInfo == null)
{
throw new Exception("Unable to parse metadata for embedded struct.");
}
payloadFetch = DynamicTraceEventData.PayloadFetch.StructPayloadFetch(offset, embeddedStructClassInfo);
break;
}
default:
{
throw new NotSupportedException($"{typeCode} is not supported.");
}
}
// Read the string name of the event payload field.
fieldNames[fieldIndex] = reader.ReadNullTerminatedUnicodeString();
// Update the offset into the event for the next payload fetch.
if (payloadFetch.Size >= DynamicTraceEventData.SPECIAL_SIZES || offset == ushort.MaxValue)
{
offset = ushort.MaxValue; // Indicate that the offset must be computed at run time.
}
else
{
offset += payloadFetch.Size;
}
// Save the current payload fetch.
fieldFetches[fieldIndex] = payloadFetch;
}
return(new DynamicTraceEventData.PayloadFetchClassInfo()
{
FieldNames = fieldNames,
FieldFetches = fieldFetches
});
}
/// <summary>
/// Creates a new MetaData instance from the serialized data at the current position of 'reader'
/// of length 'length'. This typically points at the PAYLOAD AREA of a meta-data events)
/// 'fileFormatVersionNumber' is the version number of the file as a whole
/// (since that affects the parsing of this data) and 'processID' is the process ID for the
/// whole stream (since it needs to be put into the EVENT_RECORD.
///
/// When this constructor returns the reader has read all data given to it (thus it has
/// move the read pointer by 'length')
/// </summary>
public EventPipeEventMetaData(PinnedStreamReader reader, int length, int fileFormatVersionNumber, int pointerSize, int processId)
{
StreamLabel eventDataEnd = reader.Current.Add(length);
_eventRecord = (TraceEventNativeMethods.EVENT_RECORD *)Marshal.AllocHGlobal(sizeof(TraceEventNativeMethods.EVENT_RECORD));
ClearMemory(_eventRecord, sizeof(TraceEventNativeMethods.EVENT_RECORD));
if (pointerSize == 4)
{
_eventRecord->EventHeader.Flags = TraceEventNativeMethods.EVENT_HEADER_FLAG_32_BIT_HEADER;
}
else
{
_eventRecord->EventHeader.Flags = TraceEventNativeMethods.EVENT_HEADER_FLAG_64_BIT_HEADER;
}
_eventRecord->EventHeader.ProcessId = processId;
StreamLabel metaDataStart = reader.Current;
if (fileFormatVersionNumber == 1)
{
_eventRecord->EventHeader.ProviderId = reader.ReadGuid();
}
else
{
ProviderName = reader.ReadNullTerminatedUnicodeString();
_eventRecord->EventHeader.ProviderId = GetProviderGuidFromProviderName(ProviderName);
}
var eventId = (ushort)reader.ReadInt32();
_eventRecord->EventHeader.Id = eventId;
Debug.Assert(_eventRecord->EventHeader.Id == eventId); // No truncation
var version = reader.ReadInt32();
_eventRecord->EventHeader.Version = (byte)version;
Debug.Assert(_eventRecord->EventHeader.Version == version); // No truncation
if (fileFormatVersionNumber >= 3)
{
long keywords = reader.ReadInt64();
_eventRecord->EventHeader.Keyword = (ulong)keywords;
}
int metadataLength = reader.ReadInt32();
Debug.Assert(0 <= metadataLength && metadataLength < length);
if (0 < metadataLength)
{
// TODO why do we repeat the event number it is redundant.
eventId = (ushort)reader.ReadInt32();
Debug.Assert(_eventRecord->EventHeader.Id == eventId); // No truncation
EventName = reader.ReadNullTerminatedUnicodeString();
Debug.Assert(EventName.Length < length / 2);
// Deduce the opcode from the name.
if (EventName.EndsWith("Start", StringComparison.OrdinalIgnoreCase))
{
_eventRecord->EventHeader.Opcode = (byte)TraceEventOpcode.Start;
}
else if (EventName.EndsWith("Stop", StringComparison.OrdinalIgnoreCase))
{
_eventRecord->EventHeader.Opcode = (byte)TraceEventOpcode.Stop;
}
_eventRecord->EventHeader.Keyword = (ulong)reader.ReadInt64();
// TODO why do we repeat the event number it is redundant.
version = reader.ReadInt32();
Debug.Assert(_eventRecord->EventHeader.Version == version); // No truncation
_eventRecord->EventHeader.Level = (byte)reader.ReadInt32();
Debug.Assert(_eventRecord->EventHeader.Level <= 5);
// Fetch the parameter information
int parameterCount = reader.ReadInt32();
Debug.Assert(0 <= parameterCount && parameterCount < length / 8); // Each parameter takes at least 8 bytes.
if (parameterCount > 0)
{
ParameterDefinitions = new Tuple <TypeCode, string> [parameterCount];
for (int i = 0; i < parameterCount; i++)
{
var type = (TypeCode)reader.ReadInt32();
Debug.Assert((uint)type < 24); // There only a handful of type codes.
var name = reader.ReadNullTerminatedUnicodeString();
ParameterDefinitions[i] = new Tuple <TypeCode, string>(type, name);
Debug.Assert(reader.Current <= eventDataEnd);
}
}
}
Debug.Assert(reader.Current == eventDataEnd);
}