[misc] permit using SSL on localsocket

src/main/java/org/mariadb/jdbc/internal/io/socket/UnixDomainSocket.java

@@ -85,6 +85,7 @@ public class UnixDomainSocket extends Socket {
   private final int fd;
   private InputStream is;
   private OutputStream os;
+  private boolean connected;
 
   public UnixDomainSocket(String path) throws IOException {
     if (Platform.isWindows() || Platform.isWindowsCE()) {
@@ -99,6 +100,11 @@ public UnixDomainSocket(String path) throws IOException {
     }
   }
 
+  @Override
+  public boolean isConnected() {
+    return connected;
+  }
+
   public static native int socket(int domain, int type, int protocol) throws LastErrorException;
 
   public static native int connect(int sockfd, SockAddr sockaddr, int addrlen)
@@ -130,6 +136,7 @@ public void close() throws IOException {
       } catch (LastErrorException lee) {
         throw new IOException("native close() failed : " + formatError(lee));
       }
+      connected = false;
     }
   }
 
@@ -144,6 +151,7 @@ public void connect(SocketAddress endpoint, int timeout) throws IOException {
       if (ret != 0) {
         throw new IOException(strerror(Native.getLastError()));
       }
+      connected = true;
     } catch (LastErrorException lee) {
       throw new IOException("native connect() failed : " + formatError(lee));
     }

src/main/java/org/mariadb/jdbc/internal/protocol/AbstractConnectProtocol.java

@@ -706,7 +706,7 @@ private void handleConnectionPhases(String host) throws SQLException {
 
         SSLSocketFactory sslSocketFactory = SslFactory.getSslSocketFactory(options);
         SSLSocket sslSocket = (SSLSocket) sslSocketFactory.createSocket(socket,
-            socket.getInetAddress().getHostAddress(), socket.getPort(), true);
+                socket.getInetAddress() == null ? null : socket.getInetAddress().getHostAddress(), socket.getPort(), true);
 
         enabledSslProtocolSuites(sslSocket);
         enabledSslCipherSuites(sslSocket);