*
     */
    synchronized SmbTreeHandleImpl ensureTreeConnected() throws CIFSException {
        // Optimization: Check connection validity more efficiently
        if (this.treeHandle != null && this.treeHandle.isConnected()) {
            // Connection is still valid - reuse it
            return this.treeHandle.acquire();
        }

        // Clean up old handle if needed

    class StateManagementTests {

        @Test
        @DisplayName("should correctly identify disconnected states")
        void shouldIdentifyDisconnectedStates() {
            // States: 0=not connected, 1=connecting, 2=run connected, 3=connected,
            // 4=error, 5=disconnecting, 6=disconnected/invalid
            int[] disconnectedStates = { 0, 4, 5, 6 };
            int[] connectedStates = { 1, 2, 3 };

     * @throws IOException if an I/O error occurs
     */
    protected abstract void doSkip(Long key) throws IOException;

    /**
     * Checks if the transport is disconnected.
     *
     * @return whether the transport is disconnected
     */
    public boolean isDisconnected() {
        return this.state == 4 || this.state == 5 || this.state == 6 || this.state == 0;
    }

    /**

        assertEquals(ChannelState.DISCONNECTED, channelInfo.getState());
        assertFalse(channelInfo.isPrimary());
        assertEquals(0, channelInfo.getBytesSent());
        assertEquals(0, channelInfo.getBytesReceived());
    }

    @Test
    void testStateTransitions() {
        assertEquals(ChannelState.DISCONNECTED, channelInfo.getState());
        assertFalse(channelInfo.isHealthy());

    @DisplayName("available() on SMB1 returns 0 and marks closed on disconnected statuses")
    void available_smb1_disconnectedStatuses(int status) throws Exception {
        // Verify SMB1 path: disconnected/server-closed statuses yield 0 and mark fd closed
        SmbPipeInputStream stream = newStreamWithInit(false);

        verify(transport).hasCapability(42);
    }

    // Edge: disconnected status toggles
    @ParameterizedTest
    @DisplayName("isDisconnected reflects current mocked state")
    @ValueSource(booleans = { true, false })
    void isDisconnected_states(boolean disconnected) {
        when(transport.isDisconnected()).thenReturn(disconnected);
        assertEquals(disconnected, transport.isDisconnected());

     * @throws SmbException if an error occurs checking capabilities
     */
    boolean hasCapability(int cap) throws SmbException;

    /**
     * Checks if the transport has been disconnected.
     *
     * @return whether the transport has been disconnected
     */
    boolean isDisconnected();

    /**
     * Disconnects the transport from the remote server.
     *
     * @param hard if true, force immediate disconnection

 */
package jcifs.internal.smb2.multichannel;

/**
 * SMB3 Multi-Channel connection states
 */
public enum ChannelState {
    /**
     * Channel is not connected
     */
    DISCONNECTED(0),

    /**
     * Connection establishment in progress
     */
    CONNECTING(1),

    /**
     * Authentication in progress
     */
    AUTHENTICATING(2),

    /**

	"net"
	"syscall"
	"time"
)

// CheckPortAvailability - check if given host and port is already in use.
// Note: The check method tries to listen on given port and closes it.
// It is possible to have a disconnected client in this tiny window of time.
func CheckPortAvailability(host, port string, opts TCPOptions) (err error) {
	lc := &net.ListenConfig{
		Control: func(network, address string, c syscall.RawConn) error {

            assertTrue(
                    initialState == RdmaConnection.RdmaConnectionState.DISCONNECTED
                            || initialState == RdmaConnection.RdmaConnectionState.CONNECTING,
                    "Initial state should be DISCONNECTED or CONNECTING");

            // Test connection properties
            // Note: Local address may be null for TCP fallback provider