{0x8, 0x4}: {0x1: 0x3ba5e9b41bf07f0}, {0x8, 0x5}: {0x1: 0xd7dabc15800f9d41}, {0x8, 0x6}: {0x1: 0xb482a6169fd270f}, {0x8, 0x7}: {0x1: 0x50748e0099d657e8}, {0x9, 0x1}: {0x1: 0xc77ae0144fcaeb6e}, {0x9, 0x2}: {0x1: 0x8a86c7dbebf27b68}, {0x9, 0x3}: {0x1: 0xa64e3be6d6fe7e92}, {0x9, 0x4}: {0x1: 0x239b71c41745d207}, {0x9, 0x5}: {0x1: 0x2d0803094c5a86ce}, {0x9, 0x6}: {0x1: 0xa3c2539b3af84874}, {0xa, 0x1}: {0x1: 0x7d30d91b89fcec21}, {0xa, 0x2}: {0x1: 0xfa5af9aa9f1857a3}, {0xa, 0x3}: {0x1: 0x84bc4bda8af81f90},...

  const val TYPE_SETTINGS = 0x4
  const val TYPE_PUSH_PROMISE = 0x5
  const val TYPE_PING = 0x6
  const val TYPE_GOAWAY = 0x7
  const val TYPE_WINDOW_UPDATE = 0x8
  const val TYPE_CONTINUATION = 0x9

  const val FLAG_NONE = 0x0
  const val FLAG_ACK = 0x1 // Used for settings and ping.
  const val FLAG_END_STREAM = 0x1 // Used for headers and data.
  const val FLAG_END_HEADERS = 0x4 // Used for headers and continuation.

     *
     * This method removes characters that are not allowed in XML documents
     * according to the XML 1.0 specification. Valid characters include:
     * - Tab (0x9)
     * - Line feed (0xA)
     * - Carriage return (0xD)
     * - Any character between 0x20 and 0xD7FF
     * - Any character between 0xE000 and 0xFFFD
     * - Any character between 0x10000 and 0x10FFFF
     *

  internal const val OPCODE_CONTINUATION = 0x0
  internal const val OPCODE_TEXT = 0x1
  internal const val OPCODE_BINARY = 0x2

  internal const val OPCODE_CONTROL_CLOSE = 0x8
  internal const val OPCODE_CONTROL_PING = 0x9
  internal const val OPCODE_CONTROL_PONG = 0xa

  /**
   * Maximum length of frame payload. Larger payloads, if supported by the frame type, can use the
   * special values [PAYLOAD_SHORT] or [PAYLOAD_LONG].
   */