plasma-workspace/shell/main.cpp

/*
    SPDX-FileCopyrightText: 2012 Marco Martin <mart@kde.org>
    SPDX-FileCopyrightText: 2013 Sebastian Kügler <sebas@kde.org>
    SPDX-FileCopyrightText: 2015 David Edmundson <davidedmundson@kde.org>

    SPDX-License-Identifier: GPL-2.0-or-later
*/

#include <QApplication>
#include <QCommandLineParser>
#include <QDBusConnection>
#include <QDBusMessage>
#include <QDebug>
#include <QLoggingCategory>
#include <QMessageBox>
#include <QProcess>
#include <QQmlDebuggingEnabler>
#include <QQuickWindow>
#include <QSessionManager>

#include <KAboutData>

#ifdef WITH_KUSERFEEDBACKCORE
#include "userfeedback.h"
#endif

#include <kcrash.h>
#include <kdbusservice.h>
#include <klocalizedstring.h>
#include <kworkspace.h>

#include "coronatesthelper.h"
#include "debug.h"
#include "shellcorona.h"
#include "softwarerendernotifier.h"
#include "standaloneappcorona.h"

#include <QDBusConnectionInterface>
#include <QDir>

static QLoggingCategory::CategoryFilter oldCategoryFilter;

// Qt 5.15 introduces a new syntax for connections
// framework code can't port away due to needing Qt5.12
// this filters out the warnings
// Remove this once we depend on Qt5.15 in frameworks
void filterConnectionSyntaxWarning(QLoggingCategory *category)
{
    if (qstrcmp(category->categoryName(), "qt.qml.connections") == 0) {
        category->setEnabled(QtWarningMsg, false);
    } else if (oldCategoryFilter) {
        oldCategoryFilter(category);
    }
}

int main(int argc, char *argv[])
{
#if QT_CONFIG(qml_debug)
    if (qEnvironmentVariableIsSet("PLASMA_ENABLE_QML_DEBUG")) {
        QQmlDebuggingEnabler debugger;
    }
#endif
    // Plasma scales itself to font DPI
    // on X, where we don't have compositor scaling, this generally works fine.
    // also there are bugs on older Qt, especially when it comes to fractional scaling
    // there's advantages to disabling, and (other than small context menu icons) few advantages in enabling

    // On wayland, it's different. Everything is simpler as all co-ordinates are in the same co-ordinate system
    // we don't have fractional scaling on the client so don't hit most the remaining bugs and
    // even if we don't use Qt scaling the compositor will try to scale us anyway so we have no choice
    if (!qEnvironmentVariableIsSet("PLASMA_USE_QT_SCALING")) {
        qunsetenv("QT_DEVICE_PIXEL_RATIO");
        QCoreApplication::setAttribute(Qt::AA_DisableHighDpiScaling);
    } else {
        QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
    }

    QQuickWindow::setDefaultAlphaBuffer(true);

    oldCategoryFilter = QLoggingCategory::installFilter(filterConnectionSyntaxWarning);

    const bool qpaVariable = qEnvironmentVariableIsSet("QT_QPA_PLATFORM");
    KWorkSpace::detectPlatform(argc, argv);
    QApplication app(argc, argv);
    if (!qpaVariable) {
        // don't leak the env variable to processes we start
        qunsetenv("QT_QPA_PLATFORM");
    }
    KLocalizedString::setApplicationDomain("plasmashell");

    // The executable's path is added to the library/plugin paths.
    // This does not make much sense for plasmashell.
    app.removeLibraryPath(QCoreApplication::applicationDirPath());

    KAboutData aboutData(QStringLiteral("plasmashell"), i18n("Plasma"), QStringLiteral(PROJECT_VERSION), i18n("Plasma Shell"), KAboutLicense::GPL);

    KAboutData::setApplicationData(aboutData);

    app.setQuitOnLastWindowClosed(false);

    bool replace = false;

    ShellCorona *corona;
    {
        QCommandLineParser cliOptions;

        QCommandLineOption dbgOption(QStringList() << QStringLiteral("d") << QStringLiteral("qmljsdebugger"), i18n("Enable QML Javascript debugger"));

        QCommandLineOption noRespawnOption(QStringList() << QStringLiteral("n") << QStringLiteral("no-respawn"),
                                           i18n("Do not restart plasma-shell automatically after a crash"));

        QCommandLineOption shellPluginOption(QStringList() << QStringLiteral("p") << QStringLiteral("shell-plugin"),
                                             i18n("Force loading the given shell plugin"),
                                             QStringLiteral("plugin"),
                                             ShellCorona::defaultShell());

        QCommandLineOption standaloneOption(QStringList() << QStringLiteral("a") << QStringLiteral("standalone"),
                                            i18n("Load plasmashell as a standalone application, needs the shell-plugin option to be specified"));

        QCommandLineOption replaceOption({QStringLiteral("replace")}, i18n("Replace an existing instance"));

        QCommandLineOption testOption(QStringList() << QStringLiteral("test"),
                                      i18n("Enables test mode and specifies the layout javascript file to set up the testing environment"),
                                      i18n("file"),
                                      QStringLiteral("layout.js"));

#ifdef WITH_KUSERFEEDBACKCORE
        QCommandLineOption feedbackOption(QStringList() << QStringLiteral("feedback"), i18n("Lists the available options for user feedback"));
#endif
        cliOptions.addOption(dbgOption);
        cliOptions.addOption(noRespawnOption);
        cliOptions.addOption(shellPluginOption);
        cliOptions.addOption(standaloneOption);
        cliOptions.addOption(testOption);
        cliOptions.addOption(replaceOption);
#ifdef WITH_KUSERFEEDBACKCORE
        cliOptions.addOption(feedbackOption);
#endif

        aboutData.setupCommandLine(&cliOptions);
        cliOptions.process(app);
        aboutData.processCommandLine(&cliOptions);

#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
        QGuiApplication::setFallbackSessionManagementEnabled(false);
#endif

        auto disableSessionManagement = [](QSessionManager &sm) {
            sm.setRestartHint(QSessionManager::RestartNever);
        };
        QObject::connect(&app, &QGuiApplication::commitDataRequest, disableSessionManagement);
        QObject::connect(&app, &QGuiApplication::saveStateRequest, disableSessionManagement);

        corona = new ShellCorona(&app);
        corona->setShell(cliOptions.value(shellPluginOption));
        if (!corona->kPackage().isValid()) {
            qCritical() << "starting invalid corona" << corona->shell();
            return 1;
        }

#ifdef WITH_KUSERFEEDBACKCORE
        auto userFeedback = new UserFeedback(corona, &app);
        if (cliOptions.isSet(feedbackOption)) {
            QTextStream(stdout) << userFeedback->describeDataSources();
            return 0;
        }
#endif

        QObject::connect(QCoreApplication::instance(), &QCoreApplication::aboutToQuit, corona, &QObject::deleteLater);

        if (!cliOptions.isSet(noRespawnOption) && !cliOptions.isSet(testOption)) {
            KCrash::setFlags(KCrash::AutoRestart);
        }

        if (cliOptions.isSet(testOption)) {
            const QUrl layoutUrl = QUrl::fromUserInput(cliOptions.value(testOption), {}, QUrl::AssumeLocalFile);
            if (!layoutUrl.isLocalFile()) {
                qCWarning(PLASMASHELL) << "ensure the layout file is local" << layoutUrl;
                cliOptions.showHelp(1);
            }

            QStandardPaths::setTestModeEnabled(true);
            QDir(QStandardPaths::writableLocation(QStandardPaths::ConfigLocation)).removeRecursively();
            corona->setTestModeLayout(layoutUrl.toLocalFile());

            qApp->setProperty("org.kde.KActivities.core.disableAutostart", true);

            new CoronaTestHelper(corona);
        }

        if (cliOptions.isSet(standaloneOption)) {
            if (cliOptions.isSet(shellPluginOption)) {
                app.setApplicationName(QStringLiteral("plasmashell_") + cliOptions.value(shellPluginOption));
                app.setQuitOnLastWindowClosed(true);

                KDBusService service(KDBusService::Unique);
                // This will not leak, because corona deletes itself on window close
                new StandaloneAppCorona(cliOptions.value(shellPluginOption));
                return app.exec();
            } else {
                cliOptions.showHelp(1);
            }
        } else {
            // Tells libnotificationmanager that we're the only true application that may own notification and job progress services
            qApp->setProperty("_plasma_dbus_master", true);
        }

        QObject::connect(corona, &ShellCorona::glInitializationFailed, &app, [&app]() {
            // scene graphs errors come from a thread
            // even though we process them in the main thread, app.exit could still process these events
            static bool s_multipleInvokations = false;
            if (s_multipleInvokations) {
                return;
            }
            s_multipleInvokations = true;

            qCritical("Open GL context could not be created");
            auto configGroup = KSharedConfig::openConfig()->group("QtQuickRendererSettings");
            if (configGroup.readEntry("SceneGraphBackend") != QLatin1String("software")) {
                configGroup.writeEntry("SceneGraphBackend", "software", KConfigBase::Global | KConfigBase::Persistent);
                configGroup.sync();
                QProcess::startDetached(QStringLiteral("plasmashell"), app.arguments());
            } else {
                QCoreApplication::setAttribute(Qt::AA_ForceRasterWidgets);
                QMessageBox::critical(nullptr,
                                      i18n("Plasma Failed To Start"),
                                      i18n("Plasma is unable to start as it could not correctly use OpenGL 2 or software fallback\nPlease check that your "
                                           "graphic drivers are set up correctly."));
            }
            app.exit(-1);
        });
        replace = cliOptions.isSet(replaceOption);
    }

    KDBusService service(KDBusService::Unique | KDBusService::StartupOption(replace ? KDBusService::Replace : 0));

    corona->init();
    SoftwareRendererNotifier::notifyIfRelevant();

    return app.exec();
}