/**
         * Verifies that the isOpen method returns true for an open handle.
         */
        @Test
        public void testIsOpen_ReturnsTrueWhenOpen() {
            when(smbPipeHandle.isOpen()).thenReturn(true);
            assertTrue(smbPipeHandle.isOpen(), "isOpen() should return true when the handle is open.");
        }

        /**
         * Verifies that the isOpen method returns false for a closed handle.

    @DisplayName("isOpen delegates to handle.isOpen")
    void isOpen_delegates(boolean state) throws Exception {
        // Arrange
        SmbPipeOutputStream out = newStream();
        when(handle.isOpen()).thenReturn(state);

        // Act
        boolean result = out.isOpen();

        // Assert
        assertEquals(state, result, "isOpen should reflect handle state");

        super(handle.getPipe(), th, null, 0, 0, 0);
        this.handle = handle;
    }

    /**
     * {@inheritDoc}
     *
     * @see jcifs.smb.SmbFileOutputStream#isOpen()
     */
    @Override
    public boolean isOpen() {
        return this.handle.isOpen();
    }

    @Override
    protected synchronized SmbTreeHandleImpl ensureTreeConnected() throws CIFSException {
        return this.handle.ensureTreeConnected();
    }

    }

    @Test
    void testClose() throws SmbException {
        // Mock isOpen to return false after close
        doAnswer(new Answer<Void>() {
            @Override
            public Void answer(InvocationOnMock invocation) throws Throwable {
                when(smbFile.isOpen()).thenReturn(false);
                return null;
            }
        }).when(smbFile).close(anyLong());

     */
    @Override
    void close() throws CIFSException;

    /**
     * Tests whether this file descriptor is open and valid.
     *
     * @return whether the FD is open and valid
     */
    boolean isOpen();

    /**
     * Tests whether this file descriptor was previously open but has become invalid.
     *
     * @return whether the FD was previously open but became invalid
     */
    boolean isStale();

                  override fun peek() = exchange.peekTrailers()

                  override fun get(): Headers {
                    val source = responseBody.source()
                    if (source.isOpen) {
                      source.skipAll()
                    }
                    return peek() ?: error("null trailers after exhausting response body?!")
                  }
                },

     */
    int connectionState;
    int tid;

    String share;
    String service = "?????";
    String service0;
    SmbSession session;
    boolean inDfs, inDomainDfs;
    int tree_num; // used by SmbFile.isOpen

    SmbTree(final SmbSession session, final String share, final String service) {
        this.session = session;
        this.share = share.toUpperCase();
        if (service != null && !service.startsWith("??")) {

    }

    @Override
    protected void doSendFragment(final byte[] buf, final int off, final int length, final boolean isDirect) throws IOException {
        if (out != null && !out.isOpen()) {
            throw new IOException("DCERPC pipe is no longer open");
        }

        if (in == null) {
            in = (SmbFileInputStream) pipe.getNamedPipeInputStream();
        }
        if (out == null) {

        return response;
    }

    @Override
    public void reset() throws IOException {
        if (socketChannel != null && socketChannel.isOpen()) {
            socketChannel.close();
        }
        connect();
    }

    @Override
    public int read(ByteBuffer buffer, long remoteAddress, int remoteKey, int length) throws IOException {

	// .... add more

	osMetricLast
)

var globalOSMetrics osMetrics

func init() {
	// Inject metrics.
	ioutilx.OsOpenFile = OpenFile
	ioutilx.OpenFileDirectIO = OpenFileDirectIO
	ioutilx.OsOpen = Open
}

type osMetrics struct {
	// All fields must be accessed atomically and aligned.
	operations [osMetricLast]uint64
	latency    [osMetricLast]lockedLastMinuteLatency
}

// time an os action.