source: BufferedSource,
      length: Int,
    )

    /**
     * Create or update incoming headers, creating the corresponding streams if necessary. Frames
     * that trigger this are HEADERS and PUSH_PROMISE.
     *
     * @param inFinished true if the sender will not send further frames.
     * @param streamId the stream owning these headers.

      if (associatedStreamId == 0) {
        writer.headers(outFinished, streamId, requestHeaders)
      } else {
        require(!client) { "client streams shouldn't have associated stream IDs" }
        // HTTP/2 has a PUSH_PROMISE frame.
        writer.pushPromise(associatedStreamId, streamId, requestHeaders)
      }
    }

    if (flushHeaders) {
      writer.flush()
    }

    return stream
  }