* because we might close the socket during a
             * request. However the chances are slim and the
             * retry code should ensure the overall request
             * is serviced. The alternative complicates things
             * more than I think is worth it.
             */

            if (socket != null) {
                socket.close();
                socket = null;
            }

We can't rely on application threads to read data from the socket. Application threads are transient: sometimes they're reading and writing and sometimes they're off doing application-layer things. But the socket is permanent, and it needs constant attention: we dispatch all incoming frames so the connection is good-to-go when the application layer needs it.

So we have a dedicated thread for every socket that just reads frames and dispatches them.

  }

  /**
   * Returns `true` if the socket, as currently configured, supports this connection spec. In
   * order for a socket to be compatible the enabled cipher suites and protocols must intersect.
   *
   * For cipher suites, at least one of the [required cipher suites][cipherSuites] must match the
   * socket's enabled cipher suites. If there are no required cipher suites the socket must have at
   * least one cipher suite enabled.

import okio.Sink
import okio.Socket
import okio.Source

/** Encodes HTTP requests and decodes HTTP responses. */
interface ExchangeCodec {
  /** The connection or CONNECT tunnel that owns this codec. */
  val carrier: Carrier

  /** Returns true if the response body and (possibly empty) trailers have been received. */
  val isResponseComplete: Boolean

  /** The socket that carries this exchange. */
  val socket: Socket

    val eventListener =
      object : EventListener() {
        var socket: SSLSocket? = null
        var closed = false

        override fun connectionAcquired(
          call: Call,
          connection: Connection,
        ) {
          socket = connection.socket() as SSLSocket
        }

        override fun requestHeadersStart(call: Call) {
          if (closed) {

  override fun configureTlsExtensions(
    sslSocket: SSLSocket,
    hostname: String?,
    protocols: List<Protocol>,
  ) {
    // No TLS extensions if the socket class is custom.
    if (matchesSocket(sslSocket)) {
      try {
        // Enable session tickets.
        setUseSessionTickets.invoke(sslSocket, true)

        // Assume platform support on 24+

      RecordedRequest(
        "",
        headersOf(),
        listOf(),
        0L,
        Buffer(),
        0,
        Socket(),
      )
    recordedRequest = RecordedRequest("", headersOf(), listOf(), 0L, Buffer(), 0, Socket())
    var requestUrl: HttpUrl? = recordedRequest.requestUrl
    var requestLine: String = recordedRequest.requestLine
    var method: String? = recordedRequest.method

  /** Returns the route used by this connection. */
  fun route(): Route

  /**
   * Returns the socket that this connection is using. Returns an
   * [SSL socket][javax.net.ssl.SSLSocket] if this connection is HTTPS. If this is an HTTP/2
   * connection the socket may be shared by multiple concurrent calls.
   */
  fun socket(): Socket

  /**
   * Returns the TLS handshake used to establish this connection, or null if the connection is not

// TestCopyUnixpacket tests that we can use bufio when copying
// across a unixpacket socket. This used to fail due to an unnecessary
// empty Write call that was interpreted as an EOF.
func TestCopyUnixpacket(t *testing.T) {
	tmpDir := t.TempDir()
	socket := filepath.Join(tmpDir, "unixsock")

	// Start a unixpacket server.
	addr := &net.UnixAddr{
		Name: socket,
		Net:  "unixpacket",
	}
	server, err := net.ListenUnix("unixpacket", addr)

            @Throws(IOException::class)
            override fun configureSocket(socket: Socket): Socket {
              socket.sendBufferSize = SOCKET_BUFFER_SIZE
              socket.receiveBufferSize = SOCKET_BUFFER_SIZE
              return socket
            }
          },
        ).sslSocketFactory(
          handshakeCertificates.sslSocketFactory(),