kde-playground/plasma/applets/lsof/lsof.cpp

/* 
    This file is part of the KDE project
    Copyright (C) 2024 Ivailo Monev <xakepa10@gmail.com>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License version 2, as published by the Free Software Foundation.

    This library 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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/

#include "lsof.h"

#include <QMutex>
#include <QTimer>
#include <QProcess>
#include <QTreeWidget>
#include <QHeaderView>
#include <QApplication>
#include <QGraphicsLinearLayout>
#include <Plasma/TreeWidget>
#include <KStandardDirs>
#include <KIcon>
#include <KDebug>

// TODO: option for it
static const int s_updatetimeout = 2000; // ms
static const QStringList s_lsofargs = QStringList() << QLatin1String("-Fftn");
// keeps things interactive, somewhat
static const int s_processtime = 50;

class LsofData
{
public:
    LsofData();

    QByteArray lsoffd;
    QByteArray lsoftype;
    QByteArray lsofpid;
    QByteArray lsofname;
    QTreeWidgetItem* lsofitem;

    bool operator==(const LsofData &other) const;
};

LsofData::LsofData()
    : lsofitem(nullptr)
{
}

bool LsofData::operator==(const LsofData &other) const
{
    return (
        lsoffd == other.lsoffd && lsoftype == other.lsoftype
        && lsofpid == other.lsofpid && lsofname == other.lsofname
        && lsofitem == other.lsofitem
    );
}

class LsofWidget : public QGraphicsWidget
{
    Q_OBJECT
public:
    LsofWidget(Lsof* lsof);
    ~LsofWidget();

public Q_SLOTS:
    void slotUpdateLayout();

private Q_SLOTS:
    void slotFinished(int exitcode);
    void slotTimeout();

private:
    QMutex m_mutex;
    Lsof* m_lsof;
    QGraphicsLinearLayout* m_layout;
    Plasma::TreeWidget* m_treewidget;
    QTreeWidget* m_treewidgetnative;
    QProcess* m_lsofproc;
    QTimer* m_timer;
    QString m_lsofexe;
    QList<LsofData> m_lsofdata;
};


LsofWidget::LsofWidget(Lsof* lsof)
    : QGraphicsWidget(lsof),
    m_lsof(lsof),
    m_layout(nullptr),
    m_treewidget(nullptr),
    m_treewidgetnative(nullptr),
    m_lsofproc(nullptr)
{
    m_layout = new QGraphicsLinearLayout(this);

    const QStringList treeheaders = QStringList()
        << i18n("File Descriptor")
        << i18n("Type")
        << i18n("PID")
        << i18n("Name");
    m_treewidget = new Plasma::TreeWidget(this);
    m_treewidgetnative = m_treewidget->nativeWidget();
    m_treewidgetnative->setHeaderLabels(treeheaders);
    m_treewidgetnative->setRootIsDecorated(false);
    m_treewidgetnative->header()->setMovable(false);
    m_treewidgetnative->header()->setStretchLastSection(true);
    m_treewidgetnative->header()->setResizeMode(0, QHeaderView::ResizeToContents);
    m_treewidgetnative->header()->setResizeMode(1, QHeaderView::ResizeToContents);
    m_treewidgetnative->header()->setResizeMode(2, QHeaderView::ResizeToContents);
    m_treewidgetnative->header()->setResizeMode(3, QHeaderView::Stretch);
    m_layout->addItem(m_treewidget);

    setLayout(m_layout);

    m_lsofproc = new QProcess(this);
    connect(m_lsofproc, SIGNAL(finished(int)), this, SLOT(slotFinished(int)));

    m_timer = new QTimer(this);
    m_timer->setInterval(s_updatetimeout);
    connect(m_timer, SIGNAL(timeout()), this, SLOT(slotTimeout()));
}

LsofWidget::~LsofWidget()
{
    m_timer->stop();
}

void LsofWidget::slotUpdateLayout()
{
    m_timer->stop();
    m_treewidgetnative->clear();
    m_lsofexe = KStandardDirs::findExe("lsof");
    if (m_lsofexe.isEmpty()) {
        m_lsof->showMessage(
            KIcon("dialog-warning"),
            i18n("Could not find lsof program"),
            Plasma::ButtonOk
        );
        return;
    }
    m_timer->start();
}

void LsofWidget::slotFinished(int exitcode)
{
    kDebug() << "lsof finished" << exitcode;
    m_timer->stop();
    int lsofcounter = 0;
    LsofData lsofdata;
    QList<LsofData> currentlsofdata;
    QByteArray lsofline = m_lsofproc->readLine();
    while (!lsofline.isEmpty()) {
        // qDebug() << Q_FUNC_INFO << lsofline;
        const char lsoflinetype = lsofline.at(0);
        switch (lsoflinetype) {
            case 'f': {
                lsofdata.lsoffd = lsofline.mid(1, lsofline.size() - 1);
                lsofcounter++;
                break;
            }
            case 't': {
                lsofdata.lsoftype = lsofline.mid(1, lsofline.size() - 1);
                lsofcounter++;
                break;
            }
            case 'p': {
                lsofdata.lsofpid = lsofline.mid(1, lsofline.size() - 1);
                lsofcounter++;
                break;
            }
            case 'n': {
                lsofdata.lsofname = lsofline.mid(1, lsofline.size() - 1);
                lsofcounter++;
                break;
            }
            default: {
                kWarning() << "invalid lsof line" << lsofline;
                lsofcounter = 0;
                lsofdata.lsoffd.clear();
                lsofdata.lsoftype.clear();
                lsofdata.lsofpid.clear();
                lsofdata.lsofname.clear();
                break;
            }
        }
        if (lsofcounter >= 4) {
            currentlsofdata.append(lsofdata);
        }
        QApplication::processEvents(QEventLoop::AllEvents, s_processtime);
        lsofline = m_lsofproc->readLine();
    }

    QMutableListIterator<LsofData> iter(m_lsofdata);
    while (iter.hasNext()) {
        const LsofData itercurrent = iter.next();
        if (currentlsofdata.contains(itercurrent)) {
            currentlsofdata.removeOne(itercurrent);
            QApplication::processEvents(QEventLoop::AllEvents, s_processtime);
            continue;
        }
        iter.remove();
        delete itercurrent.lsofitem;
        QApplication::processEvents(QEventLoop::AllEvents, s_processtime);
    }

    foreach (const LsofData lsofdata, currentlsofdata) {
        const QStringList lsofitemstrings = QStringList()
            << QString::fromLatin1(lsofdata.lsoffd.constData(), lsofdata.lsoffd.size())
            << QString::fromLatin1(lsofdata.lsoftype.constData(), lsofdata.lsoftype.size())
            << QString::fromLatin1(lsofdata.lsofpid.constData(), lsofdata.lsofpid.size())
            << QString::fromLatin1(lsofdata.lsofname.constData(), lsofdata.lsofname.size());
        QTreeWidgetItem* lsofitem = new QTreeWidgetItem(m_treewidgetnative, lsofitemstrings);
        lsofitem->setTextAlignment(0, Qt::AlignLeft | Qt::AlignVCenter);
        lsofitem->setTextAlignment(1, Qt::AlignLeft | Qt::AlignVCenter);
        lsofitem->setTextAlignment(2, Qt::AlignLeft | Qt::AlignVCenter);
        lsofitem->setTextAlignment(3, Qt::AlignLeft | Qt::AlignVCenter);
        lsofitem->setFlags(Qt::ItemIsSelectable | Qt::ItemIsEnabled);
        m_treewidgetnative->addTopLevelItem(lsofitem);
        QApplication::processEvents(QEventLoop::AllEvents, s_processtime);
    }

    m_lsofdata = currentlsofdata;
    m_timer->start();
}

void LsofWidget::slotTimeout()
{
    m_lsofproc->terminate();
    m_lsofproc->start(m_lsofexe, s_lsofargs);
}

Lsof::Lsof(QObject *parent, const QVariantList &args)
    : Plasma::PopupApplet(parent, args),
    m_lsofwidget(nullptr)
{
    setAspectRatioMode(Plasma::IgnoreAspectRatio);
    setPopupIcon("media-playlist-repeat");
    // NOTE: no check has to be done if it is installed
    setAssociatedApplication("ksysguard");
    adjustSize();
}

Lsof::~Lsof()
{
    delete m_lsofwidget;
}

void Lsof::init()
{
    Plasma::PopupApplet::init();
    m_lsofwidget = new LsofWidget(this);
    QTimer::singleShot(500, m_lsofwidget, SLOT(slotUpdateLayout()));
}

QGraphicsWidget *Lsof::graphicsWidget()
{
    return m_lsofwidget;
}

K_EXPORT_PLASMA_APPLET(lsof, Lsof)

#include "moc_lsof.cpp"
#include "lsof.moc"