Add UDev helper class for evdev plugins

Adopt evdevkeyboard plugin to use new UDev helper

Change-Id: Ie914c77dde9a28a8cf7f7cd972acd963c13bc698
Reviewed-by: Laszlo Agocs <laszlo.p.agocs@nokia.com>

4 files changed, 336 insertions, 2 deletions

diff --git a/src/platformsupport/udev/qudevhelper_p.h b/src/platformsupport/udev/qudevhelper_p.h
index e6046ca085..3895da87b6 100644
--- a/src/platformsupport/udev/qudevhelper_p.h
+++ b/src/platformsupport/udev/qudevhelper_p.h
@@ -43,6 +43,7 @@
 #define QUDEVHELPER_P_H
 
 #include <QString>
+#include <QObject>
 
 QT_BEGIN_NAMESPACE
 
diff --git a/src/platformsupport/udev/qudevicehelper.cpp b/src/platformsupport/udev/qudevicehelper.cpp
new file mode 100644
index 0000000000..bf3ce67b43
--- /dev/null
+++ b/src/platformsupport/udev/qudevicehelper.cpp
@@ -0,0 +1,235 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qudevicehelper_p.h"
+
+#include <QStringList>
+#include <QCoreApplication>
+#include <QObject>
+#include <QHash>
+#include <QSocketNotifier>
+
+#include <linux/input.h>
+
+//#define QT_QPA_UDEVICE_HELPER_DEBUG
+
+#ifdef QT_QPA_UDEVICE_HELPER_DEBUG
+#include <QtDebug>
+#endif
+
+QT_BEGIN_NAMESPACE
+
+QUDeviceHelper *QUDeviceHelper::createUDeviceHelper(QUDeviceTypes types, QObject *parent)
+{
+#ifdef QT_QPA_UDEVICE_HELPER_DEBUG
+    qWarning() << "Try to create new UDeviceHelper";
+#endif
+
+    QUDeviceHelper *helper = 0;
+    struct udev *udev;
+
+    udev = udev_new();
+    if (udev) {
+        helper = new QUDeviceHelper(types, udev, parent);
+    } else {
+        qWarning("Failed to get udev library context.");
+    }
+
+    return helper;
+}
+
+QUDeviceHelper::QUDeviceHelper(QUDeviceTypes types, struct udev *udev, QObject *parent) :
+    QObject(parent),
+    m_udev(udev), m_types(types), m_udevMonitor(0), m_udevMonitorFileDescriptor(-1), m_udevSocketNotifier(0)
+{
+#ifdef QT_QPA_UDEVICE_HELPER_DEBUG
+    qWarning() << "New UDeviceHelper created for type" << types;
+#endif
+
+    if (!m_udev)
+        return;
+
+    m_udevMonitor = udev_monitor_new_from_netlink(m_udev, "udev");
+    if (!m_udevMonitor) {
+#ifdef QT_QPA_UDEVICE_HELPER_DEBUG
+        qWarning("Unable to create an Udev monitor. No devices can be detected.");
+#endif
+        return;
+    }
+
+    udev_monitor_filter_add_match_subsystem_devtype(m_udevMonitor, "input", 0);
+    udev_monitor_enable_receiving(m_udevMonitor);
+    m_udevMonitorFileDescriptor = udev_monitor_get_fd(m_udevMonitor);
+
+    m_udevSocketNotifier = new QSocketNotifier(m_udevMonitorFileDescriptor, QSocketNotifier::Read, this);
+    connect(m_udevSocketNotifier, SIGNAL(activated(int)), this, SLOT(handleUDevNotification()));
+}
+
+QUDeviceHelper::~QUDeviceHelper()
+{
+    if (m_udevMonitor)
+        udev_monitor_unref(m_udevMonitor);
+
+    if (m_udev)
+        udev_unref(m_udev);
+}
+
+QStringList QUDeviceHelper::scanConnectedDevices()
+{
+    QStringList devices;
+
+    if (!m_udev)
+        return devices;
+
+    udev_enumerate *ue = udev_enumerate_new(m_udev);
+    udev_enumerate_add_match_subsystem(ue, "input");
+
+    if (m_types & UDev_Mouse)
+        udev_enumerate_add_match_property(ue, "ID_INPUT_MOUSE", "1");
+    if (m_types & UDev_Touchpad)
+        udev_enumerate_add_match_property(ue, "ID_INPUT_TOUCHPAD", "1");
+    if (m_types & UDev_Touchscreen)
+        udev_enumerate_add_match_property(ue, "ID_INPUT_TOUCHSCREEN", "1");
+    if (m_types & UDev_Keyboard)
+        udev_enumerate_add_match_property(ue, "ID_INPUT_KEYBOARD", "1");
+
+    if (udev_enumerate_scan_devices(ue) != 0) {
+#ifdef QT_QPA_UDEVICE_HELPER_DEBUG
+        qWarning() << "UDeviceHelper scan connected devices for enumeration failed";
+#endif
+        return devices;
+    }
+
+    udev_list_entry *entry;
+    udev_list_entry_foreach (entry, udev_enumerate_get_list_entry(ue)) {
+        const char *syspath = udev_list_entry_get_name(entry);
+        udev_device *udevice = udev_device_new_from_syspath(m_udev, syspath);
+        QString candidate = QString::fromUtf8(udev_device_get_devnode(udevice));
+        if (candidate.startsWith(QLatin1String("/dev/input/event")))
+            devices << candidate;
+
+        udev_device_unref(udevice);
+    }
+    udev_enumerate_unref(ue);
+
+#ifdef QT_QPA_UDEVICE_HELPER_DEBUG
+    qWarning() << "UDeviceHelper found matching devices" << devices;
+#endif
+
+    return devices;
+}
+
+void QUDeviceHelper::handleUDevNotification()
+{
+    if (!m_udevMonitor)
+        return;
+
+    struct udev_device *dev;
+    QString devNode;
+    QUDeviceTypes types = QFlag(UDev_Unknown);
+
+    dev = udev_monitor_receive_device(m_udevMonitor);
+    if (!dev)
+        goto cleanup;
+
+    const char *action;
+    action = udev_device_get_action(dev);
+    if (!action)
+        goto cleanup;
+
+    const char *str;
+    str = udev_device_get_devnode(dev);
+    if (!str)
+        goto cleanup;
+
+    devNode = QString::fromUtf8(str);
+    if (!devNode.startsWith(QLatin1String("/dev/input/event")))
+        goto cleanup;
+
+    // does not increase the refcount
+    dev = udev_device_get_parent_with_subsystem_devtype(dev, "input", 0);
+    if (!dev)
+        goto cleanup;
+
+    types = checkDeviceType(dev);
+
+    if (types && (qstrcmp(action, "add") == 0))
+        emit deviceDetected(devNode, types);
+
+    if (types && (qstrcmp(action, "remove") == 0))
+        emit deviceRemoved(devNode, types);
+
+cleanup:
+    udev_device_unref(dev);
+}
+
+QUDeviceHelper::QUDeviceTypes QUDeviceHelper::checkDeviceType(udev_device *dev)
+{
+    QUDeviceTypes types = QFlag(UDev_Unknown);
+
+    if ((m_types & UDev_Keyboard) && (qstrcmp(udev_device_get_property_value(dev, "ID_INPUT_KEYBOARD"), "1") == 0 )) {
+        const char *capabilities_key = udev_device_get_sysattr_value(dev, "capabilities/key");
+        QStringList val = QString::fromUtf8(capabilities_key).split(QString::fromUtf8(" "), QString::SkipEmptyParts);
+        if (!val.isEmpty()) {
+            bool ok;
+            unsigned long long keys = val.last().toULongLong(&ok, 16);
+            if (ok) {
+                // Tests if the letter Q is valid for the device.  We may want to alter this test, but it seems mostly reliable.
+                bool test = (keys >> KEY_Q) & 1;
+                if (test)
+                    types |= UDev_Keyboard;
+            }
+        }
+    }
+
+    if ((m_types & UDev_Mouse) && (qstrcmp(udev_device_get_property_value(dev, "ID_INPUT_MOUSE"), "1") == 0))
+        types |= UDev_Mouse;
+
+    if ((m_types & UDev_Touchpad) && (qstrcmp(udev_device_get_property_value(dev, "ID_INPUT_TOUCHPAD"), "1") == 0))
+        types |= UDev_Touchpad;
+
+    if ((m_types & UDev_Touchscreen) && (qstrcmp(udev_device_get_property_value(dev, "ID_INPUT_TOUCHSCREEN"), "1") == 0))
+        types |= UDev_Touchscreen;
+
+    return types;
+}
+
+QT_END_NAMESPACE
diff --git a/src/platformsupport/udev/qudevicehelper_p.h b/src/platformsupport/udev/qudevicehelper_p.h
new file mode 100644
index 0000000000..b7544fa6c2
--- /dev/null
+++ b/src/platformsupport/udev/qudevicehelper_p.h
@@ -0,0 +1,98 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser General Public
+** License version 2.1 as published by the Free Software Foundation and
+** appearing in the file LICENSE.LGPL included in the packaging of this
+** file. Please review the following information to ensure the GNU Lesser
+** General Public License version 2.1 requirements will be met:
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights. These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU General
+** Public License version 3.0 as published by the Free Software Foundation
+** and appearing in the file LICENSE.GPL included in the packaging of this
+** file. Please review the following information to ensure the GNU General
+** Public License version 3.0 requirements will be met:
+** http://www.gnu.org/copyleft/gpl.html.
+**
+** Other Usage
+** Alternatively, this file may be used in accordance with the terms and
+** conditions contained in a signed written agreement between you and Nokia.
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QUDEVICEHELPER_H
+#define QUDEVICEHELPER_H
+
+#include <QObject>
+#include <QSocketNotifier>
+
+#include <libudev.h>
+
+QT_BEGIN_NAMESPACE
+
+class QUDeviceHelper : public QObject
+{
+    Q_OBJECT
+    Q_ENUMS(QUDeviceType)
+
+public:
+    enum QUDeviceType {
+        UDev_Unknown = 0x00,
+        UDev_Mouse = 0x01,
+        UDev_Touchpad = 0x02,
+        UDev_Touchscreen = 0x04,
+        UDev_Keyboard = 0x08
+    };
+    Q_DECLARE_FLAGS(QUDeviceTypes, QUDeviceType)
+
+    static QUDeviceHelper *createUDeviceHelper(QUDeviceTypes type, QObject *parent);
+    ~QUDeviceHelper();
+
+    QStringList scanConnectedDevices();
+
+signals:
+    void deviceDetected(const QString &deviceNode, QUDeviceTypes types);
+    void deviceRemoved(const QString &deviceNode, QUDeviceTypes types);
+
+private slots:
+    void handleUDevNotification();
+
+private:
+    QUDeviceHelper(QUDeviceTypes types, struct udev *udev, QObject *parent = 0);
+
+    void startWatching();
+    void stopWatching();
+
+    QUDeviceTypes checkDeviceType(struct udev_device *dev);
+
+    struct udev *m_udev;
+    QUDeviceTypes m_types;
+    struct udev_monitor *m_udevMonitor;
+    int m_udevMonitorFileDescriptor;
+    QSocketNotifier *m_udevSocketNotifier;
+};
+
+Q_DECLARE_OPERATORS_FOR_FLAGS(QUDeviceHelper::QUDeviceTypes)
+
+QT_END_NAMESPACE
+
+#endif // QUDEVICEHELPER_H
diff --git a/src/platformsupport/udev/udev.pri b/src/platformsupport/udev/udev.pri
index ac3f7df40a..48ad9d36af 100644
--- a/src/platformsupport/udev/udev.pri
+++ b/src/platformsupport/udev/udev.pri
@@ -1,5 +1,5 @@
 contains(QT_CONFIG, libudev) {
-    HEADERS += $$PWD/qudevhelper_p.h
-    SOURCES += $$PWD/qudevhelper.cpp
+    HEADERS += $$PWD/qudevhelper_p.h $$PWD/qudevicehelper_p.h
+    SOURCES += $$PWD/qudevhelper.cpp $$PWD/qudevicehelper.cpp
     LIBS += -ludev
 }