* server's hostname is sent to the proxy.
 *
 * Prior to sending any CONNECT request OkHttp always calls the proxy authenticator so that it may
 * prepare preemptive authentication. OkHttp will call [authenticate] with a fake `HTTP/1.1 407
 * Proxy Authentication Required` response that has a `Proxy-Authenticate: OkHttp-Preemptive`

        // If we've exhausted upstream, we're done.
        if (upstreamBytesRead == -1L) {
          commit(upstreamPos)
          return -1L
        }

        // Update this source and prepare this call's result.
        val bytesRead = minOf(upstreamBytesRead, byteCount)
        upstreamBuffer.copyTo(sink, 0, bytesRead)
        sourcePos += bytesRead

        // Append the upstream bytes to the file.

      throw noMoreExchanges(e) as Throwable
    } finally {
      if (!calledNoMoreExchanges) {
        noMoreExchanges(null)
      }
    }
  }

  /**
   * Prepare for a potential trip through all of this call's network interceptors. This prepares to
   * find an exchange to carry the request.
   *
   * Note that an exchange will not be needed if the request is satisfied by the cache.
   *

    ```

4. Tag the release and push to GitHub.

    ```
    git commit -am "Prepare for release $RELEASE_VERSION."
    git tag -a parent-$RELEASE_VERSION -m "Version $RELEASE_VERSION"
    git push && git push --tags
    ```

5. Wait for [GitHub Actions][github_actions] to start the publish job.

6. Prepare for ongoing development and push to GitHub.

    ```
    sed -i "" \

            if (errorCode != null && !finished) {
              // Prepare to deliver an error.
              errorExceptionToDeliver = errorException ?: StreamResetException(errorCode!!)
            }

            if (closed) {
              throw IOException("stream closed")
            } else if (readBuffer.size > 0L) {
              // Prepare to read bytes. Start by moving them to the caller's buffer.

        .serialNumber(1L)
        .certificateAuthority(1)
        .commonName("root")
        .build()

    // Add a good intermediate CA, and have that issue a good certificate to localhost. Prepare an
    // SSL context for an HTTP client under attack. It includes the trusted CA and a pinned
    // certificate.
    val goodIntermediateCa =
      HeldCertificate.Builder()
        .signedBy(rootCa)

      this License, each Contributor hereby grants to You a perpetual,
      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
      copyright license to reproduce, prepare Derivative Works of,
      publicly display, publicly perform, sublicense, and distribute the
      Work and such Derivative Works in Source or Object form.

   3. Grant of Patent License. Subject to the terms and conditions of

/**
 * Unit test for [FastFallbackExchangeFinder] implementation details.
 *
 * This test uses [TaskFaker] to deterministically test racy code. Each function in this test has
 * the same structure:
 *
 *  * prepare a set of plans, each with a predictable connect delay
 *  * attempt to find a connection
 *  * step through time, asserting that the expected side effects are performed.
 */
internal class FastFallbackExchangeFinderTest {

          exchange.responseHeadersStart()
          invokeStartEvent = false
        }
        if (responseBuilder == null) {
          if (requestBody.isDuplex()) {
            // Prepare a duplex body so that the application can send a request body later.
            exchange.flushRequest()
            val bufferedRequestBody = exchange.createRequestBody(request, true).buffer()

 * limitations under the License.
 */
package okhttp3.internal.http2

import okhttp3.internal.format
import okio.ByteString.Companion.encodeUtf8

object Http2 {
  @JvmField
  val CONNECTION_PREFACE = "PRI * HTTP/2.0\r\n\r\nSM\r\n\r\n".encodeUtf8()

  /** The initial max frame size, applied independently writing to, or reading from the peer. */
  const val INITIAL_MAX_FRAME_SIZE = 0x4000 // 16384