NetworkManager based backend for QNetworkInformation

For Linux. Based on the code from the old bearer plugin for
NetworkManager with changes to fit better the objective of
QNetworkInformation.

Task-number: QTBUG-86966
Change-Id: I90c3488ff31ef6dfdcfb877c0e9c592c6c328a89
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>
(cherry picked from commit 6d85e6e45ac9efe12f01ae38619487a23c585e9e)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

5 files changed, 435 insertions, 0 deletions

diff --git a/src/plugins/networkinformationbackends/CMakeLists.txt b/src/plugins/networkinformationbackends/CMakeLists.txt
index 94a1f6baba..d1770d5eb7 100644
--- a/src/plugins/networkinformationbackends/CMakeLists.txt
+++ b/src/plugins/networkinformationbackends/CMakeLists.txt
@@ -1,3 +1,7 @@
 if(WIN32 AND QT_FEATURE_networklistmanager)
     add_subdirectory(networklistmanager)
 endif()
+
+if(LINUX)
+    add_subdirectory(networkmanager)
+endif()
diff --git a/src/plugins/networkinformationbackends/networkmanager/CMakeLists.txt b/src/plugins/networkinformationbackends/networkmanager/CMakeLists.txt
new file mode 100644
index 0000000000..44a6e0f38d
--- /dev/null
+++ b/src/plugins/networkinformationbackends/networkmanager/CMakeLists.txt
@@ -0,0 +1,12 @@
+qt_internal_add_plugin(QNetworkManagerNetworkInformationBackend
+    OUTPUT_NAME networkmanagernetworkinformationbackend
+    TYPE networkinformationbackends
+    DEFAULT_IF LINUX
+    SOURCES
+        qnetworkmanagernetworkinformationbackend.cpp
+        qnetworkmanagerservice.h
+        qnetworkmanagerservice.cpp
+    PUBLIC_LIBRARIES
+        Qt::DBus
+        Qt::NetworkPrivate
+)
diff --git a/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagernetworkinformationbackend.cpp b/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagernetworkinformationbackend.cpp
new file mode 100644
index 0000000000..1677f36fe1
--- /dev/null
+++ b/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagernetworkinformationbackend.cpp
@@ -0,0 +1,148 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtNetwork module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtNetwork/private/qnetworkinformation_p.h>
+
+#include "qnetworkmanagerservice.h"
+
+#include <QtCore/qglobal.h>
+#include <QtCore/private/qobject_p.h>
+
+#include <QtDBus/qdbusmessage.h>
+
+QT_BEGIN_NAMESPACE
+Q_DECLARE_LOGGING_CATEGORY(lcNetInfoNLM)
+Q_LOGGING_CATEGORY(lcNetInfoNM, "qt.network.info.networkmanager");
+
+namespace {
+QNetworkInformation::Reachability reachabilityFromNMState(QNetworkManagerInterface::NMState state)
+{
+    switch (state) {
+    case QNetworkManagerInterface::NM_STATE_UNKNOWN:
+    case QNetworkManagerInterface::NM_STATE_ASLEEP:
+    case QNetworkManagerInterface::NM_STATE_CONNECTING:
+        return QNetworkInformation::Reachability::Unknown;
+    case QNetworkManagerInterface::NM_STATE_DISCONNECTING: // No point in starting new connections:
+    case QNetworkManagerInterface::NM_STATE_DISCONNECTED:
+        return QNetworkInformation::Reachability::Disconnected;
+    case QNetworkManagerInterface::NM_STATE_CONNECTED_LOCAL:
+        return QNetworkInformation::Reachability::Local;
+    case QNetworkManagerInterface::NM_STATE_CONNECTED_SITE:
+        return QNetworkInformation::Reachability::Site;
+    case QNetworkManagerInterface::NM_STATE_CONNECTED_GLOBAL:
+        return QNetworkInformation::Reachability::Online;
+    }
+    return QNetworkInformation::Reachability::Unknown;
+}
+}
+
+static QString backendName = QStringLiteral("networkmanager");
+
+class QNetworkManagerNetworkInformationBackend : public QNetworkInformationBackend
+{
+    Q_OBJECT
+public:
+    QNetworkManagerNetworkInformationBackend();
+    ~QNetworkManagerNetworkInformationBackend() = default;
+
+    QString name() const override { return backendName; }
+    QNetworkInformation::Features featuresSupported() const override
+    {
+        if (!isValid())
+            return {};
+        return featuresSupportedStatic();
+    }
+
+    static QNetworkInformation::Features featuresSupportedStatic()
+    {
+        return QNetworkInformation::Features(QNetworkInformation::Feature::Reachability);
+    }
+
+    bool isValid() const { return iface.isValid(); }
+
+private:
+    QNetworkManagerInterface iface;
+    QNetworkManagerInterface::NMState prevState;
+};
+
+class QNetworkManagerNetworkInformationBackendFactory : public QNetworkInformationBackendFactory
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID QNetworkInformationBackendFactory_iid)
+    Q_INTERFACES(QNetworkInformationBackendFactory)
+public:
+    QNetworkManagerNetworkInformationBackendFactory() = default;
+    ~QNetworkManagerNetworkInformationBackendFactory() = default;
+    QString name() const override { return backendName; }
+    QNetworkInformation::Features featuresSupported() const override
+    {
+        if (!QNetworkManagerInterfaceBase::networkManagerAvailable())
+            return {};
+        return QNetworkManagerNetworkInformationBackend::featuresSupportedStatic();
+    }
+
+    QNetworkInformationBackend *create(QNetworkInformation::Features requiredFeatures) const override
+    {
+        if ((requiredFeatures & featuresSupported()) != requiredFeatures)
+            return nullptr;
+        if (!QNetworkManagerInterfaceBase::networkManagerAvailable())
+            return nullptr;
+        auto backend = new QNetworkManagerNetworkInformationBackend();
+        if (!backend->isValid())
+            delete std::exchange(backend, nullptr);
+        return backend;
+    }
+};
+
+QNetworkManagerNetworkInformationBackend::QNetworkManagerNetworkInformationBackend()
+{
+    prevState = iface.state();
+    setReachability(reachabilityFromNMState(prevState));
+    connect(&iface, &QNetworkManagerInterface::stateChanged, this, [this]() {
+        auto newState = iface.state();
+        if (newState != prevState) {
+            prevState = newState;
+            setReachability(reachabilityFromNMState(prevState));
+        }
+    });
+}
+
+QT_END_NAMESPACE
+
+#include "qnetworkmanagernetworkinformationbackend.moc"
diff --git a/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagerservice.cpp b/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagerservice.cpp
new file mode 100644
index 0000000000..da5ef955fa
--- /dev/null
+++ b/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagerservice.cpp
@@ -0,0 +1,129 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qnetworkmanagerservice.h"
+
+#include <QObject>
+#include <QList>
+#include <QtDBus/QtDBus>
+#include <QtDBus/QDBusConnection>
+#include <QtDBus/QDBusError>
+#include <QtDBus/QDBusInterface>
+#include <QtDBus/QDBusMessage>
+#include <QtDBus/QDBusReply>
+#include <QtDBus/QDBusPendingCallWatcher>
+#include <QtDBus/QDBusObjectPath>
+#include <QtDBus/QDBusPendingCall>
+
+#define DBUS_PROPERTIES_INTERFACE "org.freedesktop.DBus.Properties"
+
+QT_BEGIN_NAMESPACE
+
+QNetworkManagerInterfaceBase::QNetworkManagerInterfaceBase(QObject *parent)
+    : QDBusAbstractInterface(QLatin1String(NM_DBUS_SERVICE), QLatin1String(NM_DBUS_PATH),
+                             NM_DBUS_INTERFACE, QDBusConnection::systemBus(), parent)
+{
+}
+
+bool QNetworkManagerInterfaceBase::networkManagerAvailable()
+{
+    return QNetworkManagerInterfaceBase().isValid();
+}
+
+QNetworkManagerInterface::QNetworkManagerInterface(QObject *parent)
+    : QNetworkManagerInterfaceBase(parent)
+{
+    if (!isValid())
+        return;
+
+    PropertiesDBusInterface managerPropertiesInterface(
+            QLatin1String(NM_DBUS_SERVICE), QLatin1String(NM_DBUS_PATH), DBUS_PROPERTIES_INTERFACE,
+            QDBusConnection::systemBus());
+    QList<QVariant> argumentList;
+    argumentList << QLatin1String(NM_DBUS_INTERFACE);
+    QDBusPendingReply<QVariantMap> propsReply = managerPropertiesInterface.callWithArgumentList(
+            QDBus::Block, QLatin1String("GetAll"), argumentList);
+    if (!propsReply.isError()) {
+        propertyMap = propsReply.value();
+    } else {
+        qWarning() << "propsReply" << propsReply.error().message();
+    }
+
+    QDBusConnection::systemBus().connect(
+            QLatin1String(NM_DBUS_SERVICE), QLatin1String(NM_DBUS_PATH),
+            QLatin1String(NM_DBUS_INTERFACE), QLatin1String("PropertiesChanged"), this,
+            SLOT(setProperties(QMap<QString, QVariant>)));
+}
+
+QNetworkManagerInterface::~QNetworkManagerInterface()
+{
+    QDBusConnection::systemBus().disconnect(
+            QLatin1String(NM_DBUS_SERVICE), QLatin1String(NM_DBUS_PATH),
+            QLatin1String(NM_DBUS_INTERFACE), QLatin1String("PropertiesChanged"), this,
+            SLOT(setProperties(QMap<QString, QVariant>)));
+}
+
+QNetworkManagerInterface::NMState QNetworkManagerInterface::state()
+{
+    if (propertyMap.contains("State"))
+        return static_cast<QNetworkManagerInterface::NMState>(propertyMap.value("State").toUInt());
+    return QNetworkManagerInterface::NM_STATE_UNKNOWN;
+}
+
+void QNetworkManagerInterface::setProperties(const QMap<QString, QVariant> &map)
+{
+    for (auto i = map.cbegin(), end = map.cend(); i != end; ++i) {
+        const bool isState = i.key() == QLatin1String("State");
+        bool stateUpdate = isState;
+        auto it = propertyMap.lowerBound(i.key());
+        if (it != propertyMap.end() && it.key() == i.key()) {
+            stateUpdate &= (it.value() != i.value());
+            *it = *i;
+        } else {
+            propertyMap.insert(it, i.key(), i.value());
+        }
+
+        if (stateUpdate) {
+            quint32 state = i.value().toUInt();
+            Q_EMIT stateChanged(state);
+        }
+    }
+}
+
+QT_END_NAMESPACE
diff --git a/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagerservice.h b/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagerservice.h
new file mode 100644
index 0000000000..9624eaa216
--- /dev/null
+++ b/src/plugins/networkinformationbackends/networkmanager/qnetworkmanagerservice.h
@@ -0,0 +1,142 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QNETWORKMANAGERSERVICE_H
+#define QNETWORKMANAGERSERVICE_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API. It exists purely as an
+// implementation detail. This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <QtDBus/QDBusAbstractInterface>
+#include <QtDBus/QDBusPendingCallWatcher>
+#include <QtDBus/QDBusObjectPath>
+
+#define NM_DBUS_SERVICE "org.freedesktop.NetworkManager"
+
+#define NM_DBUS_PATH "/org/freedesktop/NetworkManager"
+#define NM_DBUS_INTERFACE "org.freedesktop.NetworkManager"
+
+// Matches 'NMDeviceState' from https://developer.gnome.org/NetworkManager/stable/nm-dbus-types.html
+enum NMDeviceState {
+    NM_DEVICE_STATE_UNKNOWN = 0,
+    NM_DEVICE_STATE_UNMANAGED = 10,
+    NM_DEVICE_STATE_UNAVAILABLE = 20,
+    NM_DEVICE_STATE_DISCONNECTED = 30,
+    NM_DEVICE_STATE_PREPARE = 40,
+    NM_DEVICE_STATE_CONFIG = 50,
+    NM_DEVICE_STATE_NEED_AUTH = 60,
+    NM_DEVICE_STATE_IP_CONFIG = 70,
+    NM_DEVICE_STATE_ACTIVATED = 100,
+    NM_DEVICE_STATE_DEACTIVATING = 110,
+    NM_DEVICE_STATE_FAILED = 120
+};
+
+QT_BEGIN_NAMESPACE
+
+// This tiny class exists for the purpose of seeing if NetworkManager is available without
+// initializing everything the derived/full class needs.
+class QNetworkManagerInterfaceBase : public QDBusAbstractInterface
+{
+    Q_OBJECT
+public:
+    QNetworkManagerInterfaceBase(QObject *parent = nullptr);
+    ~QNetworkManagerInterfaceBase() = default;
+
+    static bool networkManagerAvailable();
+
+private:
+    Q_DISABLE_COPY_MOVE(QNetworkManagerInterfaceBase)
+};
+
+class QNetworkManagerInterface final : public QNetworkManagerInterfaceBase
+{
+    Q_OBJECT
+
+public:
+    // Matches 'NMState' from https://developer.gnome.org/NetworkManager/stable/nm-dbus-types.html
+    enum NMState {
+        NM_STATE_UNKNOWN = 0,
+        NM_STATE_ASLEEP = 10,
+        NM_STATE_DISCONNECTED = 20,
+        NM_STATE_DISCONNECTING = 30,
+        NM_STATE_CONNECTING = 40,
+        NM_STATE_CONNECTED_LOCAL = 50,
+        NM_STATE_CONNECTED_SITE = 60,
+        NM_STATE_CONNECTED_GLOBAL = 70
+    };
+    Q_ENUM(NMState);
+
+    QNetworkManagerInterface(QObject *parent = nullptr);
+    ~QNetworkManagerInterface();
+
+    NMState state();
+
+Q_SIGNALS:
+    void stateChanged(quint32);
+
+private Q_SLOTS:
+    void setProperties(const QMap<QString, QVariant> &map);
+
+private:
+    Q_DISABLE_COPY_MOVE(QNetworkManagerInterface)
+
+    QVariantMap propertyMap;
+};
+
+class PropertiesDBusInterface : public QDBusAbstractInterface
+{
+public:
+    PropertiesDBusInterface(const QString &service, const QString &path, const QString &interface,
+                            const QDBusConnection &connection, QObject *parent = 0)
+        : QDBusAbstractInterface(service, path, interface.toLatin1().data(), connection, parent)
+    {
+    }
+};
+
+QT_END_NAMESPACE
+
+#endif