* true when removing a connection from the pool; otherwise a racing caller might get it from the
   * pool when it shouldn't. Symmetrically, this must always be checked before returning a
   * connection from the pool.
   *
   * Once true this is always true. Guarded by this.
   */
  var noNewExchanges = false

  /**

    Previously OkHttp used its connection pool as a lock when making changes to connections and
    calls. With this change each connection is locked independently.

 *  Upgrade: [Okio 2.7.0][okio_2_7_0].

    ```kotlin
    implementation("com.squareup.okio:okio:2.7.0")
    ```

    callback.await(server.url("/a")).assertFailure("Canceled", "Socket closed", "Socket is closed")
  }

  @Test
  fun cancelAll() {
    val call = client.newCall(Request(server.url("/")))
    call.enqueue(callback)
    client.dispatcher.cancelAll()
    callback.await(server.url("/")).assertFailure("Canceled", "Socket closed", "Socket is closed")
  }

  @Test
  fun cancelWhileRequestHeadersAreSent() {

    private var closed: Boolean = false

    override fun timeout(): Timeout = timeout

    override fun write(
      source: Buffer,
      byteCount: Long,
    ) {
      check(!closed) { "closed" }
      checkOffsetAndCount(source.size, 0, byteCount)
      sink.write(source, byteCount)
    }

    override fun flush() {

 * server may not have had time to close the socket. The socket will be closed at an indeterminate
 * point before or during the second request. It may be closed after client has started sending the
 * request body. If a request body is not retryable then the client may fail the request, making
 * client behavior non-deterministic. Add delays in the client to improve the chances that the
 * server has closed the socket before follow up requests are made.
 */

   * Returns the name of the server the client requested via the SNI (Server Name Indication)
   * attribute in the TLS handshake. Unlike the rest of the HTTP exchange, this name is sent in
   * cleartext and may be monitored or blocked by a proxy or other middlebox.
   */
  val handshakeServerNames: List<String>

  init {
    if (socket is SSLSocket) {
      try {
        this.handshake = socket.session.handshake()

    val delegate = delegate
    if (delegate != null) {
      this.delegate = null
      delegate.onClosed(webSocket, code, reason)
    } else {
      events.add(Closed(code, reason))
    }
  }

  override fun onFailure(
    webSocket: WebSocket,
    t: Throwable,
    response: Response?,
  ) {
    Platform.get().log("[WS $name] onFailure", Platform.INFO, t)

    assertThat(source1.readUtf8(10)).isEqualTo("abcdefghij")
    assertThat(source1.exhausted()).isTrue()
    source1.close()
    assertThat(relay1.isClosed).isTrue()

    // Since relay1 is closed, new sources cannot be created.
    assertThat(relay1.newSource()).isNull()
    val relay2 = read(file)
    assertThat(relay2.metadata()).isEqualTo(metadata)
    val source2 = relay2.newSource()!!.buffer()

    val partAbc = parts.nextPart()!!
    val partMno = parts.nextPart()!!

    assertFailsWith<IllegalStateException> {
      partAbc.body.request(20)
    }.also { expected ->
      assertThat(expected).hasMessage("closed")
    }

    assertThat(partMno.body.readUtf8()).isEqualTo("mnop")
    assertThat(parts.nextPart()).isNull()
  }

  @Test fun `cannot read part after calling close`() {
    val multipart =
      """

import okhttp3.internal.http.parseChallenges
import okio.Buffer

/**
 * An HTTP response. Instances of this class are not immutable: the response body is a one-shot
 * value that may be consumed only once and then closed. All other properties are immutable.
 *
 * This class implements [Closeable]. Closing it simply closes its response body. See
 * [ResponseBody] for an explanation and examples.
 */
class Response internal constructor(