Qtの基礎 - シャットダウン

概要

Qtライブラリを使用して、ソフトウェアからOSのシャットダウンや再起動等を行う方法を記載する。

シャットダウン

 void Converter::shutdown()
 {
    bool shutdown_works = false;
    bool gnome_power1 = false;
    bool gnome_power2 = false;
    bool hal_works = false;
    QDBusMessage response;
 
    // GNOME
    QDBusInterface gnomeSessionManager("org.gnome.SessionManager", "/org/gnome/SessionManager", "org.gnome.SessionManager", QDBusConnection::sessionBus());
 
    response = gnomeSessionManager.call("RequestShutdown");
 
    if(response.type() == QDBusMessage::ErrorMessage)
    {
       if(verbose)
          qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
       gnome_power1 = QProcess::startDetached("gnome-power-cmd.sh shutdown");
       gnome_power2 = QProcess::startDetached("gnome-power-cmd shutdown");
 
       if(verbose && !gnome_power1 && !gnome_power2)
          qWarning() << "W: gnome-power-cmd and gnome-power-cmd.sh didn't work";
    }
    else
    {
       shutdown_works = true;
    }
 
    // KDE
    QDBusInterface kdeSessionManager("org.kde.ksmserver", "/KSMServer", "org.kde.KSMServerInterface", QDBusConnection::sessionBus());
 
    response = kdeSessionManager.call("logout", 0, 2, 2);
 
    if(response.type() == QDBusMessage::ErrorMessage)
    {
       if(verbose)
       {
          qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
       }
    }
    else
    {
       shutdown_works = true;
    }
 
    if(!shutdown_works && !gnome_power1 && !gnome_power2)
    {
       QDBusInterface powermanagement("org.freedesktop.Hal", "/org/freedesktop/Hal/devices/computer",
                                      "org.freedesktop.Hal.Device.SystemPowerManagement", QDBusConnection::systemBus());
 
       response = powermanagement.call("Shutdown");
       if(response.type() == QDBusMessage::ErrorMessage)
       {
          if(verbose)
          {
             qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
          }
       }
       else
       {
          hal_works = true;
       }
    }
 
    if(!hal_works && !shutdown_works && !gnome_power1 && !gnome_power2)
    {
       QDBusInterface powermanagement("org.freedesktop.ConsoleKit", "/org/freedesktop/ConsoleKit/Manager",
                                      "org.freedesktop.ConsoleKit.Manager", QDBusConnection::systemBus());
 
       response = powermanagement.call("Stop");
 
       if(response.type() == QDBusMessage::ErrorMessage)
       {
          if(verbose)
          {
             qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
          }
          QProcess::startDetached("sudo shutdown -P now");
       }
    }
 }

再起動

 void Converter::reboot()
 {
    bool reboot_works = false;
    bool gnome_power1 = false;
    bool gnome_power2 = false;
    bool hal_works = false;
    QDBusMessage response;
 
    // GNOME
    QDBusInterface gnomeSessionManager("org.gnome.SessionManager", "/org/gnome/SessionManager", "org.gnome.SessionManager", QDBusConnection::sessionBus());
    response = gnomeSessionManager.call("RequestReboot");
    if(response.type() == QDBusMessage::ErrorMessage)
    {
       if(verbose)
       {
          qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
       }
       gnome_power1 = QProcess::startDetached("gnome-power-cmd.sh reboot");
       gnome_power2 = QProcess::startDetached("gnome-power-cmd reboot");
       if(verbose && !gnome_power1 && !gnome_power2)
       {
          qWarning() << "W: gnome-power-cmd and gnome-power-cmd.sh didn't work";
       }
    }
    else
    {
       reboot_works = true;
    }
 
    // KDE
    QDBusInterface kdeSessionManager("org.kde.ksmserver", "/KSMServer", "org.kde.KSMServerInterface", QDBusConnection::sessionBus());
    response = kdeSessionManager.call("logout", 0, 2, 1);
 
    if(response.type() == QDBusMessage::ErrorMessage)
    {
       if(verbose)
       {
          qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
       }
    }
    else
    {
       reboot_works = true;
    }
 
    if(!reboot_works && !gnome_power1 && !gnome_power2)
    {
       QDBusInterface powermanagement("org.freedesktop.Hal", "/org/freedesktop/Hal/devices/computer", "org.freedesktop.Hal.Device.SystemPowerManagement",
                                      QDBusConnection::systemBus());
       response = powermanagement.call("Reboot");
       if(response.type() == QDBusMessage::ErrorMessage)
       {
          if(verbose)
          {
             qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
          }
       }
       else
       {
          hal_works = true;
       }
    }
 
    if(!hal_works && !reboot_works && !gnome_power1 && !gnome_power2)
    {
       QDBusInterface powermanagement("org.freedesktop.ConsoleKit", "/org/freedesktop/ConsoleKit/Manager", "org.freedesktop.ConsoleKit.Manager",
                                      QDBusConnection::systemBus());
       response = powermanagement.call("Restart");
 
       if(response.type() == QDBusMessage::ErrorMessage)
       {
          if(verbose)
          {
             qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
          }
          QProcess::startDetached("sudo shutdown -r now");
       }
    }
 }

サスペンド(スリープ)

 void Converter::suspend()
 {
    bool gnome_power1 = false;
    bool gnome_power2 = false;
    bool hal_works = false;
    QDBusMessage response;
 
    gnome_power1 = QProcess::startDetached("gnome-power-cmd.sh suspend");
    gnome_power2 = QProcess::startDetached("gnome-power-cmd suspend");
 
    if(!gnome_power1 && !gnome_power2 && verbose)
    {
       qWarning() << "W: gnome-power-cmd and gnome-power-cmd.sh didn't work";
    }
 
    if(!gnome_power1 && !gnome_power2)
    {
       QDBusInterface powermanagement("org.freedesktop.Hal", "/org/freedesktop/Hal/devices/computer",
                                      "org.freedesktop.Hal.Device.SystemPowerManagement", QDBusConnection::systemBus());
       response = powermanagement.call("Suspend", 0);
 
       if(response.type() == QDBusMessage::ErrorMessage)
       {
          if(verbose)
          {
             qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
          }
       }
       else
       {
          hal_works = true;
       }
    }
 
    if(!hal_works && !gnome_power1 && !gnome_power2)
    {
       QDBusInterface powermanagement("org.freedesktop.DeviceKit.Power", "/org/freedesktop/DeviceKit/Power",
                                      "org.freedesktop.DeviceKit.Power", QDBusConnection::systemBus());
       response = powermanagement.call("Suspend");
 
       if(response.type() == QDBusMessage::ErrorMessage)
       {
          if(verbose)
          {
             qWarning() << "W: " << response.errorName() << ":" << response.errorMessage();
          }
       }
    }
 }

ハイバネート

• GNOME Power Managementコマンドを実行する場合

 #include <QProcess>
 
 void Converter::hibernate()
 {
    // GNOME Power Management コマンドを試行
    if (QProcess::startDetached("gnome-power-cmd.sh hibernate") ||
       QProcess::startDetached("gnome-power-cmd hibernate")) {
       qInfo() << "Hibernation initiated via GNOME Power Management.";
       return;
    }
 
    qWarning() << "GNOME Power Management commands failed. Trying DBus methods.";
 }

• D-Busを使用する場合

 #include <QDBusInterface>
 #include <QDBusReply>
 #include <QDebug>
 
 void Converter::hibernate()
 {
    // HAL (Hardware Abstraction Layer) を試行
    QDBusInterface halPower("org.freedesktop.Hal", 
                            "/org/freedesktop/Hal/devices/computer",
                            "org.freedesktop.Hal.Device.SystemPowerManagement", 
                            QDBusConnection::systemBus());
 
    if (halPower.isValid()) {
       QDBusReply<void> reply = halPower.call("Hibernate");
       if (reply.isValid()) {
          qInfo() << "Hibernation initiated via HAL.";
          return;
       }
       qWarning() << "HAL hibernation failed:" << reply.error().message();
    }
    else {
       qWarning() << "Failed to connect to HAL power management.";
    }
 
    // DeviceKit Powerを試行
    QDBusInterface dkPower("org.freedesktop.DeviceKit.Power", 
                           "/org/freedesktop/DeviceKit/Power",
                           "org.freedesktop.DeviceKit.Power", 
                           QDBusConnection::systemBus());
    
    if (dkPower.isValid()) {
        QDBusReply<void> reply = dkPower.call("Hibernate");
        if (reply.isValid()) {
            qInfo() << "Hibernation initiated via DeviceKit Power.";
            return;
       }
       qWarning() << "DeviceKit Power hibernation failed:" << reply.error().message();
    }
    else {
       qWarning() << "Failed to connect to DeviceKit Power.";
    }
 
    qCritical() << "All hibernation methods failed.";
 }

画面のロック

QDBusモジュールを使用して、GNOMEスクリーンセーバーのD-Busインターフェースに接続して、Lockメソッドを呼び出してスクリーンをロックしている。

 #include <QDBus>
 #include <QMessageBox>
 
 void Converter::lock()
 {
    QDBusInterface screensaver("org.gnome.ScreenSaver", "/org/gnome/ScreenSaver", "org.gnome.ScreenSaver");
 
    if (!screensaver.isValid()) {
        QMessageBox::warning(this, "Error", "Unable to connect to GNOME ScreenSaver.", QMessageBox::Ok);
        return;
    }
 
    QDBusReply<void> reply = screensaver.call("Lock");
 
    if (!reply.isValid()) {
        QMessageBox::warning(this, "Error", "Unable to lock computer: " + reply.error().message(), QMessageBox::Ok);
    }
 }