TvnAssistServer.h

// Copyright (C) 2009,2010,2011,2012 GlavSoft LLC.
// All rights reserved.
//
//-------------------------------------------------------------------------
// This file is part of the TightVNC software.  Please visit our Web site:
//
//                       http://www.tightvnc.com/
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//-------------------------------------------------------------------------
//

#ifndef _TVN_ASSIST_SERVER_H_
#define _TVN_ASSIST_SERVER_H_

#include "util/CommonHeader.h"

#include "desktop/WinServiceDesktopFactory.h"
#include "desktop/ApplicationDesktopFactory.h"
#include "tvnserver-app/RfbClientManager.h"
#include "tvnserver-app/RfbServer.h"
#include "tvnserver-app/ExtraRfbServers.h"
#include "tvnserver-app/ControlServer.h"
#include "tvnserver-app/TvnServerListener.h"

#include "http-server-lib/HttpServer.h"

#include "thread/ZombieKiller.h"
#include "thread/LocalMutex.h"
#include "log-writer/LogWriter.h"
#include "util/Singleton.h"
#include "util/ListenerContainer.h"
#include "tvnserver-app/NewConnectionEvents.h"

#include "server-config-lib/Configurator.h"

#include "tvncontrol-app/TvnServerInfo.h"
#include "tvnserver-app/LogInitListener.h"

/**
 * TightVNC server singleton that includes serveral components:
 *   1) Zombie killer singleton.
 *   2) Configurator singleton.
 *   3) Log singleton.
 *   4) Rfb servers (main rfb server and extra servers).
 *   5) Http server.
 *   6) Control server.
 *   7) Other features:
     1) Do action when last client disconnects.
 */
class TvnAssistServer : public Singleton<TvnAssistServer>,
    public ListenerContainer<TvnServerListener*>,
    public ConfigReloadListener,
    public RfbClientManagerEventListener
{
public:
    bool runServer;
    /**
     * Creates and starts TightVNC server execution (in separate thread).
     *
     * Makes sereval steps:
     *  1) Instanizes zombie killer.
     *  2) Instanizes configurator and load configuration.
     *  3) Instanizes log.
     *  4) Starts all servers.
     *
     * @param runsInServiceContext must be set to true if TvnServer is running in service context,
     * false, if in context of single application. Parameter determinates control client behavour and
     * initial place for loading TightVNC configuration.
     *
     * @remark doesn't block calling thread execution cause all servers runs in it's own threads.
     * To know when need to shutdown TightVNC server you need to use addListener method.
     */
    TvnAssistServer(bool runsInServiceContext,
        NewConnectionEvents* newConnectionEvents,
        LogInitListener* logInitListener,
        Logger* logger);
    /**
     * Stops and destroys TightVNC server.
     * @remark don't generate shutdown signal(like shutdown() method does) for listeners.
     */
    virtual ~TvnAssistServer();

    /**
     * Fills structure with information of current state of TvnServer.
     * @param info [out] output parameter that will contain TightVNC server information
     * after call of this method.
     * @fixme place extended information to server info.
     */
    void getServerInfo(TvnServerInfo* info);

    RfbClientManager getRfbClientManager();
    /**
     * Inherited from ConfigReloadListener interface to catch configuration reload event.
     *
     * Make several things:
     *  1) Changes log level.
     *  2) Restarts rfb servers.
     *  3) Restarts http server.
     */
    virtual void onConfigReload(ServerConfig* serverConfig);

    /**
     * Only generates shutdown signal (event) for TvnServer listeners.
     *
     * @remark used by ControlClient, when it recieves command to shutdown TightVNC.
     * @remark doesn't stop TightVNC server.
     * @fixme rename this method.
     */
    void generateExternalShutdownSignal();

    /**
     * Checks if TightVNC server runs in service context.
     * @returns true if runs in service context.
     * @deprecated use getServerInfo() instead or move to private.
     */
    bool isRunningAsService() const;

    /**
     * Implemented from RfbClientManagerEventListener.
     *
     * Does nothing.
     */
    virtual void afterFirstClientConnect();

    /**
     * Implemented from RfbClientManagerEventListener.
     *
     * Does specifed in configuration action when last client disconnects from
     * rfb server.
     */
    virtual void afterLastClientDisconnect();

protected:
    void restartHttpServer();
    void restartControlServer();
    void restartMainRfbServer();

    void stopHttpServer();
    void stopControlServer();
    void stopMainRfbServer();

    // Calls a callback function to change update log properties.
    void changeLogProps();

protected:
    LogWriter m_log;
    ZombieKiller m_zombieKiller;

    Configurator m_config;
    /**
     * Shortcut to global server configuration.
     */
    ServerConfig* m_srvConfig;

    /**
     * Mutex for protecting servers.
     */
    LocalMutex m_mutex;

    /**
     * Flag that determitates if we run in server context.
     * true if service, false if application.
     */
    const bool m_runAsService;


    WinServiceDesktopFactory m_serviceDesktopFactory;
    ApplicationDesktopFactory m_applicationDesktopFactory;
    /**
     * Rfb client manager (for all rfb servers), used by rfb servers
     * rfb clients, control server and control clients.
     */
    RfbClientManager* m_rfbClientManager;
    /**
     * Control server.
     */
    ControlServer* m_controlServer;
    /**
     * Builtin http server.
     */
    HttpServer* m_httpServer;
    /**
     * Main rfb server.
     */
    RfbServer* m_rfbServer;
    /**
     * Extra servers for extra ports. This object is not protected by any mutex
     * and it does not implement any internal locking, so it should be used with
     * caution. Here we change its state on owner creation, on owner deletion
     * and on each configuration change (via a listener function called from
     * other threads). The listener function is registered after the object
     * creation and unregistered before the owner destruction, and its calls are
     * properly synchronized. Thus, we can be sure that m_extraRfbServers is not
     * used by different threads simultaneously.
     */
    ExtraRfbServers m_extraRfbServers;

    LogInitListener* m_logInitListener;

    UINT m_contextSwitchResolution; // in ms
};

#endif