Return empty string when can't take slice for snippet from buffer

server/parser.go

@@ -663,7 +663,7 @@ parseErr:
 func protoSnippet(start int, buf []byte) string {
 	stop := start + PROTO_SNIPPET_SIZE
 	bufSize := len(buf)
-	if start == bufSize {
+	if start <= bufSize {
 		return ""
 	}
 	if stop > bufSize {