private Source source(Source source) {
      return new ForwardingSource(source) {
        long totalBytesRead = 0L;

        @Override public long read(Buffer sink, long byteCount) throws IOException {
          long bytesRead = super.read(sink, byteCount);
          // read() returns the number of bytes read, or -1 if this source is exhausted.
          totalBytesRead += bytesRead != -1 ? bytesRead : 0;

        var closed = false

        override fun close() {
          closed = true
        }

        override fun read(
          sink: Buffer,
          byteCount: Long,
        ): Long {
          check(!closed)
          return data.read(sink, byteCount)
        }

        override fun timeout(): Timeout = Timeout.NONE
      }
    return source.buffer().asResponseBody(null, -1)
  }

  private fun newResponse(

      contentType: MediaType? = null,
      offset: Int = 0,
      byteCount: Int = size,
    ): RequestBody {
      checkOffsetAndCount(size.toLong(), offset.toLong(), byteCount.toLong())
      return object : RequestBody() {
        override fun contentType() = contentType

        override fun contentLength() = byteCount.toLong()

        override fun writeTo(sink: BufferedSink) {

) : ForwardingSink(delegate) {
  private var hasErrors = false

  override fun write(
    source: Buffer,
    byteCount: Long,
  ) {
    if (hasErrors) {
      source.skip(byteCount)
      return
    }
    try {
      super.write(source, byteCount)
    } catch (e: IOException) {
      hasErrors = true
      onException(e)
    }
  }

  override fun flush() {
    if (hasErrors) {

   * @param source location of data corresponding with this stream ID.
   * @param byteCount number of bytes to read or skip from the source.
   * @param last when true, there are no data frames to follow.
   */
  @Throws(IOException::class)
  fun onData(
    streamId: Int,
    source: BufferedSource,
    byteCount: Int,
    last: Boolean,
  ): Boolean

  /** Indicates the reason why this stream was canceled. */

          private var completed = false

          override fun write(
            source: Buffer,
            byteCount: Long,
          ) {
            super.write(source, byteCount)
            totalBytesWritten += byteCount
            progressListener.update(totalBytesWritten, contentLength(), completed)
          }

          override fun close() {
            super.close()

    sink: Sink,
    private val file: Path,
  ) : ForwardingSink(sink) {
    override fun write(
      source: Buffer,
      byteCount: Long,
    ) {
      if (writeFaults.contains(file)) {
        throw IOException("boom!")
      } else {
        super.write(source, byteCount)
      }
    }
  }

  /**
   * Peeks up to [byteCount] bytes from the response body and returns them as a new response
   * body. If fewer than [byteCount] bytes are in the response body, the full response body is
   * returned. If more than [byteCount] bytes are in the response body, the returned value
   * will be truncated to [byteCount] bytes.
   *

      printEvent("requestHeadersEnd");
    }

    @Override public void requestBodyStart(Call call) {
      printEvent("requestBodyStart");
    }

    @Override public void requestBodyEnd(Call call, long byteCount) {
      printEvent("requestBodyEnd");
    }

    @Override public void requestFailed(Call call, IOException ioe) {
      printEvent("requestFailed");
    }

    countBytes: Boolean,
  ): Long {
    var byteCount = 0L
    val buffer: Buffer = if (countBytes) Buffer() else sink!!.buffer

    for (i in 0 until encodedNames.size) {
      if (i > 0) buffer.writeByte('&'.code)
      buffer.writeUtf8(encodedNames[i])
      buffer.writeByte('='.code)
      buffer.writeUtf8(encodedValues[i])
    }

    if (countBytes) {
      byteCount = buffer.size
      buffer.clear()
    }