*
   * If this does write a value, it will write a tag and a length and a full value.
   */
  fun toDer(
    writer: DerWriter,
    value: T,
  )

  fun toDer(value: T): ByteString {
    val buffer = Buffer()
    val writer = DerWriter(buffer)
    toDer(writer, value)
    return buffer.readByteString()
  }

  /**

  fun setClient(client: Boolean) {
    if (this.client == client) return
    this.client = client
    writer = Http2Writer(bytesOut, client)
  }

  fun acceptFrame() {
    frameCount++
  }

  /** Maximum length of an outbound data frame.  */
  fun maxOutboundDataLength(): Int = writer.maxDataLength()

  /** Count of frames sent or received.  */
  fun frameCount(): Int = frameCount

 * [system DNS service][SYSTEM], which is the default. Some applications may provide their own
 * implementation to use a different DNS server, to prefer IPv6 addresses, to prefer IPv4 addresses,
 * or to force a specific known IP address.
 *
 * Implementations of this interface must be safe for concurrent use.
 */
fun interface Dns {
  /**

            .withQueryStringParameter("name", "peter"),
        )
        .respond(response().withBody("Peter the person!"))

      val client =
        OkHttpClient.Builder()
          .proxy(Proxy(SOCKS, InetSocketAddress(socks5Proxy.host, socks5Proxy.firstMappedPort)))
          .build()

      val response =
        client.newCall(
          Request("http://mockserver:1080/person?name=peter".toHttpUrl()),
        ).execute()

  internal class StoriesTestProvider : SimpleProvider() {
    override fun arguments(): List<Any> = createStories(RAW_DATA)
  }

  private val bytesOut = Buffer()
  private val hpackWriter = Hpack.Writer(out = bytesOut)

  @ParameterizedTest
  @ArgumentsSource(StoriesTestProvider::class)
  fun testRoundTrip(story: Story) {
    assumeFalse(
      story === Story.MISSING,

    if (!string.regionMatches(pos, PREFIX_STRING, 0, 4, ignoreCase = true)) {
      result.writeUtf8(string, pos, limit)
      return true
    }

    var pos = pos + 4 // 'xn--'.size.

    // We'd prefer to operate directly on `result` but it doesn't offer insertCodePoint(), only
    // appendCodePoint(). The Punycode algorithm processes code points in increasing code-point
    // order, not in increasing index order.

/** Returns true if this string is not a host name and might be an IP address. */
fun String.canParseAsIpAddress(): Boolean = VERIFY_AS_IP_ADDRESS.matches(this)

/**
 * Returns true if the length is not valid for DNS (empty or greater than 253 characters), or if any
 * label is longer than 63 characters. Trailing dots are okay.
 */
internal fun String.containsInvalidLabelLengths(): Boolean {
  if (length !in 1..253) return true

  var labelStart = 0

## Version 4.7.0

_2020-05-17_

 *  New: `HandshakeCertificates.Builder.addInsecureHost()` makes it easy to turn off security in
    private development environments that only carry test data. Prefer this over creating an
    all-trusting `TrustManager` because only hosts on the allowlist are insecure. From
    [our DevServer sample][dev_server]:

    ```kotlin

    inputStream.close()
    val elapsedNanos = System.nanoTime() - startNanos
    val elapsedMillis = TimeUnit.NANOSECONDS.toMillis(elapsedNanos)

    // If we're working correctly, this should be greater than 100ms, but less than double that.
    // Previously we had a bug where we would download the entire response body as long as no
    // individual read took longer than 100ms.
    assertThat(elapsedMillis).isLessThan(500L)

      } catch (_: NumberFormatException) {
        invalidLengths(strings)
      }
    }

    /** Append space-prefixed lengths to [writer]. */
    @Throws(IOException::class)
    internal fun writeLengths(writer: BufferedSink) {
      for (length in lengths) {
        writer.writeByte(' '.code).writeDecimalLong(length)
      }
    }

    @Throws(IOException::class)