char[] buf = new char[DEFAULT_BUF_SIZE];
    int nRead;
    long total = 0;
    while ((nRead = from.read(buf)) != -1) {
      to.write(buf, 0, nRead);
      total += nRead;
    }
    return total;
  }

  /**
   * Reads all characters from a {@link Readable} object into a {@link String}. Does not close the
   * {@code Readable}.
   *
   * @param r the object to read from

}

func (r *checksumReader) Read(b []byte) (n int, err error) {
	if r.err != nil {
		return 0, r.err
	}
	n, err = r.rc.Read(b)
	r.hash.Write(b[:n])
	r.nread += uint64(n)
	if r.nread > r.f.UncompressedSize64 {
		return 0, ErrFormat
	}
	if err == nil {
		return
	}
	if err == io.EOF {
		if r.nread != r.f.UncompressedSize64 {
			return 0, io.ErrUnexpectedEOF
		}

     *
     * @param b the byte array to read data into
     * @return the number of bytes read, or -1 if end of file is reached
     * @throws SmbException if an I/O error occurs
     */
    public int read(final byte b[]) throws SmbException {
        return read(b, 0, b.length);
    }

    /**
     * Reads up to len bytes from the file into the specified byte array.
     *

      }
    }

    override fun read(
      sink: Buffer,
      byteCount: Long,
    ): Long {
      require(byteCount >= 0L) { "byteCount < 0: $byteCount" }
      check(!closed) { "closed" }
      if (bytesRemaining == 0L) return -1

      val read = super.read(sink, minOf(bytesRemaining, byteCount))
      if (read == -1L) {

    /** The next byte to read. This is always less than or equal to [upstreamPos]. */
    private var sourcePos = 0L

    /**
     * Selects where to find the bytes for a read and read them. This is one of three sources.
     *
     * ## Upstream
     *
     * In this case the current thread is assigned as the upstream reader. We read bytes from

		Method: Deflate,
		Mode:   0755 | fs.ModeDevice | fs.ModeCharDevice,
	},
}

func TestWriter(t *testing.T) {
	largeData := make([]byte, 1<<17)
	if _, err := rand.Read(largeData); err != nil {
		t.Fatal("rand.Read failed:", err)
	}
	writeTests[1].Data = largeData
	defer func() {
		writeTests[1].Data = nil
	}()

	// write a zip file
	buf := new(bytes.Buffer)
	w := NewWriter(buf)

    }

    @Test
    @DisplayName("readn should handle multiple read calls")
    void testReadnMultipleCalls() throws IOException {
        when(mockInputStream.read(any(byte[].class), anyInt(), anyInt())).thenReturn(2) // First read returns 2 bytes
                .thenReturn(2) // Second read returns 2 bytes
                .thenReturn(1); // Third read returns 1 byte

        byte[] buffer = new byte[10];

        // Read first message
        assertEquals(1, sis.read());
        assertEquals(2, sis.read());

        // Read second message
        assertEquals(3, sis.read());
        assertEquals(4, sis.read());
        assertEquals(5, sis.read());

        // After all data is consumed, next read throws IOException
        assertThrows(IOException.class, () -> sis.read());
    }

    @Test

            SMBUtil.writeInt2(17, buffer, 0); // Structure size
            SMBUtil.writeInt2(0, buffer, 2); // Reserved
            SMBUtil.writeInt4(-1, buffer, 4); // Count (will be read as unsigned)
            SMBUtil.writeInt4(-2, buffer, 8); // Remaining (will be read as unsigned)
            SMBUtil.writeInt4(0, buffer, 12); // WriteChannelInfoOffset/Length

            int bytesRead = response.readBytesWireFormat(buffer, 0);

     * @param len length of data to read
     * @return number of bytes read
     */
    protected abstract int readSetupWireFormat(byte[] buffer, int bufferIndex, int len);

    /**
     * Reads parameters from wire format
     * @param buffer source buffer
     * @param bufferIndex starting index in source buffer
     * @param len length of data to read
     * @return number of bytes read