locality and performance OkHttp attempts to use the same pooled connection across redirects and
    follow-ups. It independently shares connections when the IP addresses and certificates match,
    even if the host names do not. In 4.4.0 we introduced a regression where we shared a connection

 *
 * This class supports [asynchronous canceling][cancel]. This is intended to have the smallest
 * blast radius possible. If an HTTP/2 stream is active, canceling will cancel that stream but not
 * the other streams sharing its connection. But if the TLS handshake is still in progress then
 * canceling may break the entire connection.
 */
class RealCall(
  val client: OkHttpClient,

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package okhttp3.tls.internal.der

import okio.ByteString

/**
 * Like a [ByteString], but whose bits are not necessarily a strict multiple of 8.
 */
internal data class BitString(
  val byteString: ByteString,
  /** 0-7 unused bits in the last byte. */
  val unusedBitsCount: Int,
) {

    expectedEvents += "ConnectEnd"
    expectedEvents += "ConnectionAcquired"
    expectedEvents += "RequestHeadersStart"
    expectedEvents += "RequestHeadersEnd"
    expectedEvents += "RequestBodyStart"
    // ... but we can read the response even after writing the request fails.
    expectedEvents += "RequestFailed"
    expectedEvents += "ResponseHeadersStart"
    expectedEvents += "ResponseHeadersEnd"

     * The pool will routinely try to pre-emptively open connections to satisfy this minimum.
     * Connections will still be closed if they idle beyond the keep-alive but will be replaced.
     */
    @JvmField val minimumConcurrentCalls: Int = 0,
    /** How long to wait to retry pre-emptive connection attempts that fail. */
    @JvmField val backoffDelayMillis: Long = 60 * 1000,

    if (address.url.host == this.route().address.url.host) {
      return true // This connection is a perfect match.
    }

    // At this point we don't have a hostname match. But we still be able to carry the request if
    // our connection coalescing requirements are met. See also:
    // https://hpbn.co/optimizing-application-delivery/#eliminate-domain-sharding

        importResults.writeOut(sink)
      }
    }

  /**
   * These assertions ensure the [PublicSuffixDatabase] remains correct. The specification is
   * very flexible regarding wildcard rules, but this flexibility is not something currently used
   * in practice. To simplify the implementation, we've avoided implementing the flexible rules in

    require(length < bytesOut.size - lastFrame.start)

    // Move everything from bytesOut into a new buffer.
    val fullBuffer = Buffer()
    bytesOut.read(fullBuffer, bytesOut.size)

    // Copy back all but what we're truncating.
    fullBuffer.read(bytesOut, lastFrame.start + length)
    outFrames.add(OutFrame(lastFrame.sequence, lastFrame.start, true))
    return writer
  }

  fun takeFrame(): InFrame = inFrames.take()

### EventListener.Factory

In the preceding example we used a field, `callStartNanos`, to track the elapsed time of each event. This is handy, but it won’t work if multiple calls are executing concurrently. To accommodate this, use a `Factory` to create a new `EventListener` instance for each `Call`. This allows each listener to keep call-specific state.

      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.
    val codePoints = mutableListOf<Int>()