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etw/eventdata.go

@@ -5,10 +5,18 @@ import (
 	"encoding/binary"
 )
 
+// EventData maintains a buffer which builds up the data for an ETW event. It
+// needs to be paired with EventMetadata which describes the event.
 type EventData struct {
 	buffer bytes.Buffer
 }
 
+// NewEventData returns a new EventData with an empty buffer.
+func NewEventData() *EventData {
+	return &EventData{}
+}
+
+// AddString appends the data for a string to the end of the buffer.
 func (ed *EventData) AddString(data string) {
 	binary.Write(&ed.buffer, binary.LittleEndian, []byte(data))
 	binary.Write(&ed.buffer, binary.LittleEndian, byte(0))