* @throws SmbException
     */
    synchronized SmbFileHandleImpl ensureOpen() throws CIFSException {
        if (this.handle == null || !this.handle.isValid()) {
            // one extra acquire to keep this open till the stream is released
            if (this.file instanceof SmbNamedPipe) {
                this.handle = this.file.openUnshared(SmbConstants.O_EXCL, ((SmbNamedPipe) this.file).getPipeType() & 0xFF0000, this.sharing,

            assertEquals(16, bytesRead);
            assertEquals(2048, response.getCount());
            assertEquals(1024, response.getRemaining());
        }

        @Test
        @DisplayName("Should handle zero count and remaining")
        void testReadZeroValues() throws SMBProtocolDecodingException {
            byte[] buffer = createValidWriteResponse(0, 0);

	// There is flow control in both directions.
	StreamHandler struct {
		// Handle an incoming request. Initial payload is sent.
		// Additional input packets (if any) are streamed to request.
		// Upstream will block when request channel is full.
		// Response packets can be sent at any time.
		// Any non-nil error sent as response means no more responses are sent.
		Handle StreamHandlerFn

		// Subroute for handler.

        // When
        int bytesWritten = response.writeBytesWireFormat(buffer, offset);

        // Then
        assertEquals(0, bytesWritten);
    }

    @Test
    @DisplayName("Should handle error response structure size 9")
    void testReadBytesWireFormatErrorResponse() throws Exception {
        // Given
        byte[] buffer = new byte[256];
        int bufferIndex = 0;

        // Then
        assertNotNull(exception);
        assertEquals(message, exception.getMessage());
        assertEquals(cause, exception.getCause());
    }

    @Test
    @DisplayName("Should handle null message gracefully")
    void testNullMessage() {
        // When/Then
        assertDoesNotThrow(() -> {
            RuntimeCIFSException exception = new RuntimeCIFSException((String) null);

     * @param host
     * @return tree handle
     * @throws IOException
     */
    public synchronized SmbTreeHandleImpl connectHost(final SmbResourceLocatorImpl loc, final String host) throws IOException {
        return connectHost(loc, host, null);
    }

    /**
     *
     * @param loc
     * @param host
     * @param referral
     * @return tree handle
     * @throws IOException
     */

        assertEquals(0xDE, buffer[1] & 0xFF);
        assertEquals(0xBC, buffer[2] & 0xFF);
        assertEquals(0x9A, buffer[3] & 0xFF);
    }

    @Test
    @DisplayName("Should handle big endian encoding/decoding")
    void testBigEndianOperations() {
        // Given
        int value = 0x12345678;
        byte[] buffer = new byte[4];

        // When - encode big endian

        @Test
        @DisplayName("Should handle null buffer in decode")
        void testNullBuffer() {
            FileFsSizeInformation info = new FileFsSizeInformation();

            assertThrows(NullPointerException.class, () -> {
                info.decode(null, 0, 0);
            });
        }

        @Test
        @DisplayName("Should handle insufficient buffer length")

        assertEquals("Expected structureSize = 9", exception.getMessage());
    }

    @Test
    @DisplayName("Should handle empty notification list")
    void testEmptyNotificationList() throws Exception {
        // Given
        byte[] buffer = new byte[256];
        int offset = 0;

        setHeaderStart(response, 64);

    setDefault(Dispatcher.class, Dispatcher.immediate());
  }

  private static class DummySubscriber {

    private final EventBus eventBus = new EventBus();

    @Subscribe
    public void handle(@Nullable Object unused) {}

    Subscriber toSubscriber() throws Exception {
      return Subscriber.create(eventBus, this, subscriberMethod());
    }

    SubscriberExceptionContext toContext() {