static WebSocketHTTPD serveHttpsWithWebsockets_server;
static int serveHttpsWithWebsockets_port = 8443;

static new TreeSet<String> serveHttpsWithWebsockets_peers;

// factory: func(NanoHTTPD.IHTTPSession) -> WebSocket
static int serveHttpsWithWebsockets(int port, File keystore, S pass, O factory) ctex {
  serveHttpsWithWebsockets_port = port;
  serveHttpsWithWebsockets_server = new WebSocketHTTPD(port, factory);
  serveHttpsWithWebsockets_server.makeSecure(serveHttps_makeSSLSocketFactory(keystore, pass));
serveHttpsWithWebsockets_server.start();
  ret serveHttpsWithWebsockets_port();
}

// serve on random port, return port number used
static int serveHttpsWithWebsockets(File keystore, S pass, O factory) {
  serveHttpsWithWebsockets(0, keystore, pass, factory);
  ret serveHttpsWithWebsockets_port();
}

static int serveHttpsWithWebsockets_port() {
  ret serveHttpsWithWebsockets_server == null ? 0 : serveHttpsWithWebsockets_server.getListeningPort();
}

static void cleanMeUp_serveHttpsWithWebsockets() {
  if (serveHttpsWithWebsockets_server != null) {
    serveHttpsWithWebsockets_server.stop();
    serveHttpsWithWebsockets_server = null;
  }
}

Began life as a copy of #1009197