* sequence. Returns the unescaped string, or null if the buffer isn't prefixed with a
 * double-quoted string.
 */
@Throws(EOFException::class)
private fun Buffer.readQuotedString(): String? {
  require(readByte() == '\"'.code.toByte())
  val result = Buffer()
  while (true) {
    val i = indexOfElement(QUOTED_STRING_DELIMITERS)
    if (i == -1L) return null // Unterminated quoted string.

      apply {
        val maxAgeSeconds = maxAge.inWholeSeconds
        require(maxAgeSeconds >= 0) { "maxAge < 0: $maxAgeSeconds" }
        this.maxAgeSeconds = maxAgeSeconds.commonClampToInt()
      }

    fun maxStale(maxStale: Duration) =
      apply {
        val maxStaleSeconds = maxStale.inWholeSeconds
        require(maxStaleSeconds >= 0) { "maxStale < 0: $maxStaleSeconds" }

  return null
}

internal fun Headers.Builder.commonBuild(): Headers = Headers(namesAndValues.toTypedArray())

internal fun headersCheckName(name: String) {
  require(name.isNotEmpty()) { "name is empty" }
  for (i in name.indices) {
    val c = name[i]
    require(c in '\u0021'..'\u007e') {
      "Unexpected char 0x${c.charCode()} at $i in header name: $name"
    }
  }
}

internal fun headersCheckValue(

    flags: Int,
  ) {
    if (type != TYPE_WINDOW_UPDATE && logger.isLoggable(FINE)) {
      logger.fine(frameLog(false, streamId, length, type, flags))
    }
    require(length <= maxFrameSize) { "FRAME_SIZE_ERROR length > $maxFrameSize: $length" }
    require(streamId and 0x80000000.toInt() == 0) { "reserved bit set: $streamId" }
    sink.writeMedium(length)
    sink.writeByte(type and 0xff)
    sink.writeByte(flags and 0xff)

  ) : SerialTask {
    override fun start() {
      taskRunner.assertThreadHoldsLock()
      require(currentTask == this)
      activeThreads++

      tasksExecutor.execute {
        taskRunner.assertThreadDoesntHoldLock()
        require(currentTask == this)
        try {
          runnable.run()
          require(currentTask == this) { "unexpected current task: $currentTask" }
        } finally {

  val millis = unit.toMillis(duration)
  require(millis <= Integer.MAX_VALUE) { "$name too large" }
  require(millis != 0L || duration <= 0L) { "$name too small" }
  return millis.toInt()
}

internal fun checkDuration(
  name: String,
  duration: Duration,
): Int {
  check(!duration.isNegative()) { "$name < 0" }
  val millis = duration.inWholeMilliseconds
  require(millis <= Integer.MAX_VALUE) { "$name too large" }

        if (currentPart == this) {
          currentPart = null
        }
      }

      override fun read(
        sink: Buffer,
        byteCount: Long,
      ): Long {
        require(byteCount >= 0L) { "byteCount < 0: $byteCount" }
        check(currentPart == this) { "closed" }

        source.timeout().intersectWith(timeout) {

lifetime based on Response cache headers.

 - CallStart 
 - **CacheMiss**
 - ProxySelectStart
 - ... Standard Events ...
 - CallEnd
        
### Conditional Cache Hit
 
When cache flags require checking the cache results are still valid an early cacheConditionalHit event is
received followed by a cache hit or miss.  Critically in the cache hit scenario the server won’t send the response body.

 * that makes `java.net.URL` unusable for many things. It shouldn't be used as a [Map] key or in a
 * [Set]. Doing so is both inefficient because equality may require a DNS lookup, and incorrect
 * because unequal URLs may be equal because of how they are hosted.
 *
 * ### Equal URLs should be equal
 *
 * These two URLs are semantically identical, but `java.net.URI` disagrees:
 *

    if (proxy.type() == Proxy.Type.DIRECT || proxy.type() == Proxy.Type.SOCKS) {
      socketHost = address.url.host
      socketPort = address.url.port
    } else {
      val proxyAddress = proxy.address()
      require(proxyAddress is InetSocketAddress) {
        "Proxy.address() is not an InetSocketAddress: ${proxyAddress.javaClass}"
      }
      socketHost = proxyAddress.socketHost
      socketPort = proxyAddress.port
    }