streamId: Int,
  ) {
    if (streamId == 0) throw IOException("PROTOCOL_ERROR: TYPE_DATA streamId == 0")

    // TODO: checkState open or half-closed (local) or raise STREAM_CLOSED
    val inFinished = flags and FLAG_END_STREAM != 0
    val gzipped = flags and FLAG_COMPRESSED != 0
    if (gzipped) {
      throw IOException("PROTOCOL_ERROR: FLAG_COMPRESSED without SETTINGS_COMPRESS_DATA")
    }

   */
  @Throws(IOException::class)
  fun checkLowercase(name: ByteString): ByteString {
    for (i in 0 until name.size) {
      if (name[i] in 'A'.code.toByte()..'Z'.code.toByte()) {
        throw IOException("PROTOCOL_ERROR response malformed: mixed case name: ${name.utf8()}")
      }
    }
    return name
  }