* should give up.
 *
 * When reactive authentication is requested by an origin web server, the response code is 401
 * and the implementation should respond with a new request that sets the "Authorization" header.
 *
 * ```java
 * if (response.request().header("Authorization") != null) {
 *   return null; // Give up, we've already failed to authenticate.
 * }
 *

          override fun authenticate(
            route: Route?,
            response: Response,
          ): Request? {
            if (response.request.header("Authorization") != null) {
              return null // Give up, we've already attempted to authenticate.
            }

            println("Authenticating for response: $response")
            println("Challenges: ${response.challenges()}")

        init(null, arrayOf<TrustManager>(trustManager), null)
      }.socketFactory
    } catch (e: GeneralSecurityException) {
      throw AssertionError("No System TLS: $e", e) // The system has no TLS. Just give up.
    }
  }

  override fun toString(): String = javaClass.simpleName

  companion object {
    @Volatile private var platform = findPlatform()

    const val INFO = 4
    const val WARN = 5

    while (pos < limit) {
      var dot = string.indexOf('.', startIndex = pos)
      if (dot == -1) dot = limit

      if (!encodeLabel(string, pos, dot, result)) {
        // If we couldn't encode the label, give up.
        return null
      }

      if (dot < limit) {
        result.writeByte('.'.code)
        pos = dot + 1
      } else {
        break
      }
    }

    return result.readUtf8()
  }

    response1.body.source().timeout().timeout(100, TimeUnit.MILLISECONDS)
    assertContent("This connection won't pool properly", response1)
    assertThat(server.takeRequest().sequenceNumber).isEqualTo(0)

    // Give the server time to enact the socket policy if it's one that could happen after the
    // client has received the response.
    Thread.sleep(500)
    val response2 = getResponse(newRequest("/b"))

        .addInterceptor(BrotliInterceptor)
        .build()
    ```

    This artifact has a dependency on Google's Brotli decoder (95 KiB).

 *  New: `EventListener.proxySelectStart()`, `proxySelectEnd()` events give visibility into the
    proxy selection process.
 *  New: `Response.byteString()` reads the entire response into memory as a byte string.
 *  New: `OkHttpClient.x509TrustManager` accessor.

    val key = key(request.url)
    val snapshot: DiskLruCache.Snapshot =
      try {
        cache[key] ?: return null
      } catch (_: IOException) {
        return null // Give up because the cache cannot be read.
      }

    val entry: Entry =
      try {
        Entry(snapshot.getSource(ENTRY_METADATA))
      } catch (_: IOException) {
        snapshot.closeQuietly()

        }
        val priorResponse = userResponse.priorResponse
        if (priorResponse != null && priorResponse.code == HTTP_CLIENT_TIMEOUT) {
          // We attempted to retry and got another timeout. Give up.
          return null
        }

        if (retryAfter(userResponse, 0) > 0) {
          return null
        }

        return userResponse.request
      }

      HTTP_UNAVAILABLE -> {

    e: IOException,
  )

  /**
   * Called when the HTTP response was successfully returned by the remote server. The callback may
   * proceed to read the response body with [Response.body]. The response is still live until its
   * response body is [closed][ResponseBody]. The recipient of the callback may consume the response
   * body on another thread.
   *

    @JvmField val PREFIX_DIRTY = "OkHttp DIRTY :(\n".encodeUtf8()
    private const val FILE_HEADER_SIZE = 32L

    /**
     * Creates a new relay that reads a live stream from [upstream], using [file] to share that data
     * with other sources.
     *
     * **Warning:** callers to this method must immediately call [newSource] to create a source and