Reorganize devicediscovery header

As pointed out in 13b939c7f41bceb2061e549923eab242326e9bb5 the approach
qdevicediscovery_p.h takes is just wrong. The defines it relies on will
often be missing when the header is included from random places in qtbase.
This results in different class layouts. It was working only because the
interface of the class is very limited and the public part was matching
regardless of having the macro defined.

This is now corrected by introducing subclasses and a common, non-variated
base class. QDEVICEDISCOVERY_UDEV is removed completely.

Change-Id: I9c83b5b041440a3a6ea3a604eee4a325d4d74439
Reviewed-by: Louai Al-Khanji <louai.al-khanji@theqtcompany.com>
Reviewed-by: Jørgen Lind <jorgen.lind@theqtcompany.com>

8 files changed, 235 insertions, 67 deletions

diff --git a/src/platformsupport/devicediscovery/devicediscovery.pri b/src/platformsupport/devicediscovery/devicediscovery.pri
index 9748129225..1ac25da901 100644
--- a/src/platformsupport/devicediscovery/devicediscovery.pri
+++ b/src/platformsupport/devicediscovery/devicediscovery.pri
@@ -3,14 +3,15 @@ HEADERS += $$PWD/qdevicediscovery_p.h
 linux {
     contains(QT_CONFIG, libudev) {
         SOURCES += $$PWD/qdevicediscovery_udev.cpp
+        HEADERS += $$PWD/qdevicediscovery_udev_p.h
         INCLUDEPATH += $$QMAKE_INCDIR_LIBUDEV
         LIBS_PRIVATE += $$QMAKE_LIBS_LIBUDEV
-        # Use our own define. QT_NO_LIBUDEV may not be set on non-Linux systems.
-        DEFINES += QDEVICEDISCOVERY_UDEV
     } else: contains(QT_CONFIG, evdev) {
         SOURCES += $$PWD/qdevicediscovery_static.cpp
+        HEADERS += $$PWD/qdevicediscovery_static_p.h
     } else {
         SOURCES += $$PWD/qdevicediscovery_dummy.cpp
+        HEADERS += $$PWD/qdevicediscovery_dummy_p.h
     }
 } else {
     SOURCES += $$PWD/qdevicediscovery_dummy.cpp
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_dummy.cpp b/src/platformsupport/devicediscovery/qdevicediscovery_dummy.cpp
index c6b8610bab..44c5f845dc 100644
--- a/src/platformsupport/devicediscovery/qdevicediscovery_dummy.cpp
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_dummy.cpp
@@ -31,34 +31,23 @@
 **
 ****************************************************************************/
 
-#include "qdevicediscovery_p.h"
+#include "qdevicediscovery_dummy_p.h"
 
 QT_BEGIN_NAMESPACE
 
 QDeviceDiscovery *QDeviceDiscovery::create(QDeviceTypes types, QObject *parent)
 {
-    return new QDeviceDiscovery(types, parent);
+    return new QDeviceDiscoveryDummy(types, parent);
 }
 
-QDeviceDiscovery::QDeviceDiscovery(QDeviceTypes types, QObject *parent)
-    : QObject(parent),
-      m_types(types)
+QDeviceDiscoveryDummy::QDeviceDiscoveryDummy(QDeviceTypes types, QObject *parent)
+    : QDeviceDiscovery(types, parent)
 {
 }
 
-QDeviceDiscovery::~QDeviceDiscovery()
-{
-}
-
-QStringList QDeviceDiscovery::scanConnectedDevices()
+QStringList QDeviceDiscoveryDummy::scanConnectedDevices()
 {
     return QStringList();
 }
 
-bool QDeviceDiscovery::checkDeviceType(const QString &device)
-{
-    Q_UNUSED(device);
-    return false;
-}
-
 QT_END_NAMESPACE
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_dummy_p.h b/src/platformsupport/devicediscovery/qdevicediscovery_dummy_p.h
new file mode 100644
index 0000000000..93a676858d
--- /dev/null
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_dummy_p.h
@@ -0,0 +1,63 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** 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 Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/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 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QDEVICEDISCOVERY_DUMMY_H
+#define QDEVICEDISCOVERY_DUMMY_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 "qdevicediscovery_p.h"
+
+QT_BEGIN_NAMESPACE
+
+class QDeviceDiscoveryDummy : public QDeviceDiscovery
+{
+    Q_OBJECT
+
+public:
+    QDeviceDiscoveryDummy(QDeviceTypes types, QObject *parent = 0);
+    QStringList scanConnectedDevices() Q_DECL_OVERRIDE;
+};
+
+QT_END_NAMESPACE
+
+#endif // QDEVICEDISCOVERY_DUMMY_H
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_p.h b/src/platformsupport/devicediscovery/qdevicediscovery_p.h
index 07e7996a60..f3b0d19a7c 100644
--- a/src/platformsupport/devicediscovery/qdevicediscovery_p.h
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_p.h
@@ -49,10 +49,6 @@
 #include <QSocketNotifier>
 #include <QStringList>
 
-#ifdef QDEVICEDISCOVERY_UDEV
-#include <libudev.h>
-#endif
-
 #define QT_EVDEV_DEVICE_PATH "/dev/input/"
 #define QT_EVDEV_DEVICE_PREFIX "event"
 #define QT_EVDEV_DEVICE QT_EVDEV_DEVICE_PATH QT_EVDEV_DEVICE_PREFIX
@@ -84,39 +80,18 @@ public:
     Q_DECLARE_FLAGS(QDeviceTypes, QDeviceType)
 
     static QDeviceDiscovery *create(QDeviceTypes type, QObject *parent = 0);
-    ~QDeviceDiscovery();
 
-    QStringList scanConnectedDevices();
+    virtual QStringList scanConnectedDevices() = 0;
 
 signals:
     void deviceDetected(const QString &deviceNode);
     void deviceRemoved(const QString &deviceNode);
 
-#ifdef QDEVICEDISCOVERY_UDEV
-private slots:
-    void handleUDevNotification();
-#endif
-
-private:
-#ifdef QDEVICEDISCOVERY_UDEV
-    QDeviceDiscovery(QDeviceTypes types, struct udev *udev, QObject *parent = 0);
-    bool checkDeviceType(struct udev_device *dev);
-#else
-    QDeviceDiscovery(QDeviceTypes types, QObject *parent = 0);
-    bool checkDeviceType(const QString &device);
-#endif
+protected:
+    QDeviceDiscovery(QDeviceTypes types, QObject *parent) : QObject(parent), m_types(types) { }
+    Q_DISABLE_COPY(QDeviceDiscovery)
 
     QDeviceTypes m_types;
-
-#ifdef QDEVICEDISCOVERY_UDEV
-    void startWatching();
-    void stopWatching();
-
-    struct udev *m_udev;
-    struct udev_monitor *m_udevMonitor;
-    int m_udevMonitorFileDescriptor;
-    QSocketNotifier *m_udevSocketNotifier;
-#endif
 };
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(QDeviceDiscovery::QDeviceTypes)
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_static.cpp b/src/platformsupport/devicediscovery/qdevicediscovery_static.cpp
index eb7c17d59e..660d3760fb 100644
--- a/src/platformsupport/devicediscovery/qdevicediscovery_static.cpp
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_static.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "qdevicediscovery_p.h"
+#include "qdevicediscovery_static_p.h"
 
 #include <QStringList>
 #include <QCoreApplication>
@@ -75,23 +75,18 @@ QT_BEGIN_NAMESPACE
 
 QDeviceDiscovery *QDeviceDiscovery::create(QDeviceTypes types, QObject *parent)
 {
-    return new QDeviceDiscovery(types, parent);
+    return new QDeviceDiscoveryStatic(types, parent);
 }
 
-QDeviceDiscovery::QDeviceDiscovery(QDeviceTypes types, QObject *parent) :
-    QObject(parent),
-    m_types(types)
+QDeviceDiscoveryStatic::QDeviceDiscoveryStatic(QDeviceTypes types, QObject *parent)
+    : QDeviceDiscovery(types, parent)
 {
 #ifdef QT_QPA_DEVICE_DISCOVERY_DEBUG
     qWarning() << "New DeviceDiscovery created for type" << types;
 #endif
 }
 
-QDeviceDiscovery::~QDeviceDiscovery()
-{
-}
-
-QStringList QDeviceDiscovery::scanConnectedDevices()
+QStringList QDeviceDiscoveryStatic::scanConnectedDevices()
 {
     QStringList devices;
     QDir dir;
@@ -124,7 +119,7 @@ QStringList QDeviceDiscovery::scanConnectedDevices()
     return devices;
 }
 
-bool QDeviceDiscovery::checkDeviceType(const QString &device)
+bool QDeviceDiscoveryStatic::checkDeviceType(const QString &device)
 {
     bool ret = false;
     int fd = QT_OPEN(device.toLocal8Bit().constData(), O_RDONLY | O_NDELAY, 0);
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_static_p.h b/src/platformsupport/devicediscovery/qdevicediscovery_static_p.h
new file mode 100644
index 0000000000..6629a9a26c
--- /dev/null
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_static_p.h
@@ -0,0 +1,66 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** 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 Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/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 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QDEVICEDISCOVERY_STATIC_H
+#define QDEVICEDISCOVERY_STATIC_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 "qdevicediscovery_p.h"
+
+QT_BEGIN_NAMESPACE
+
+class QDeviceDiscoveryStatic : public QDeviceDiscovery
+{
+    Q_OBJECT
+
+public:
+    QDeviceDiscoveryStatic(QDeviceTypes types, QObject *parent = 0);
+    QStringList scanConnectedDevices() Q_DECL_OVERRIDE;
+
+private:
+    bool checkDeviceType(const QString &device);
+};
+
+QT_END_NAMESPACE
+
+#endif // QDEVICEDISCOVERY_STATIC_H
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_udev.cpp b/src/platformsupport/devicediscovery/qdevicediscovery_udev.cpp
index 006b18552e..7645dc4544 100644
--- a/src/platformsupport/devicediscovery/qdevicediscovery_udev.cpp
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_udev.cpp
@@ -31,7 +31,7 @@
 **
 ****************************************************************************/
 
-#include "qdevicediscovery_p.h"
+#include "qdevicediscovery_udev_p.h"
 
 #include <QStringList>
 #include <QCoreApplication>
@@ -60,7 +60,7 @@ QDeviceDiscovery *QDeviceDiscovery::create(QDeviceTypes types, QObject *parent)
 
     udev = udev_new();
     if (udev) {
-        helper = new QDeviceDiscovery(types, udev, parent);
+        helper = new QDeviceDiscoveryUDev(types, udev, parent);
     } else {
         qWarning("Failed to get udev library context.");
     }
@@ -68,9 +68,9 @@ QDeviceDiscovery *QDeviceDiscovery::create(QDeviceTypes types, QObject *parent)
     return helper;
 }
 
-QDeviceDiscovery::QDeviceDiscovery(QDeviceTypes types, struct udev *udev, QObject *parent) :
-    QObject(parent),
-    m_types(types), m_udev(udev), m_udevMonitor(0), m_udevMonitorFileDescriptor(-1), m_udevSocketNotifier(0)
+QDeviceDiscoveryUDev::QDeviceDiscoveryUDev(QDeviceTypes types, struct udev *udev, QObject *parent) :
+    QDeviceDiscovery(types, parent),
+    m_udev(udev), m_udevMonitor(0), m_udevMonitorFileDescriptor(-1), m_udevSocketNotifier(0)
 {
 #ifdef QT_QPA_DEVICE_DISCOVERY_DEBUG
     qWarning() << "New UDeviceHelper created for type" << types;
@@ -96,7 +96,7 @@ QDeviceDiscovery::QDeviceDiscovery(QDeviceTypes types, struct udev *udev, QObjec
     connect(m_udevSocketNotifier, SIGNAL(activated(int)), this, SLOT(handleUDevNotification()));
 }
 
-QDeviceDiscovery::~QDeviceDiscovery()
+QDeviceDiscoveryUDev::~QDeviceDiscoveryUDev()
 {
     if (m_udevMonitor)
         udev_monitor_unref(m_udevMonitor);
@@ -105,7 +105,7 @@ QDeviceDiscovery::~QDeviceDiscovery()
         udev_unref(m_udev);
 }
 
-QStringList QDeviceDiscovery::scanConnectedDevices()
+QStringList QDeviceDiscoveryUDev::scanConnectedDevices()
 {
     QStringList devices;
 
@@ -165,7 +165,7 @@ QStringList QDeviceDiscovery::scanConnectedDevices()
     return devices;
 }
 
-void QDeviceDiscovery::handleUDevNotification()
+void QDeviceDiscoveryUDev::handleUDevNotification()
 {
     if (!m_udevMonitor)
         return;
@@ -216,7 +216,7 @@ cleanup:
     udev_device_unref(dev);
 }
 
-bool QDeviceDiscovery::checkDeviceType(udev_device *dev)
+bool QDeviceDiscoveryUDev::checkDeviceType(udev_device *dev)
 {
     if (!dev)
         return false;
diff --git a/src/platformsupport/devicediscovery/qdevicediscovery_udev_p.h b/src/platformsupport/devicediscovery/qdevicediscovery_udev_p.h
new file mode 100644
index 0000000000..d31ba72c96
--- /dev/null
+++ b/src/platformsupport/devicediscovery/qdevicediscovery_udev_p.h
@@ -0,0 +1,79 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the plugins of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL21$
+** 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 Digia. For licensing terms and
+** conditions see http://qt.digia.com/licensing. For further information
+** use the contact form at http://qt.digia.com/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 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file. Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Digia gives you certain additional
+** rights. These rights are described in the Digia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QDEVICEDISCOVERY_UDEV_H
+#define QDEVICEDISCOVERY_UDEV_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 "qdevicediscovery_p.h"
+#include <libudev.h>
+
+QT_BEGIN_NAMESPACE
+
+class QDeviceDiscoveryUDev : public QDeviceDiscovery
+{
+    Q_OBJECT
+
+public:
+    QDeviceDiscoveryUDev(QDeviceTypes types, struct udev *udev, QObject *parent = 0);
+    ~QDeviceDiscoveryUDev();
+    QStringList scanConnectedDevices() Q_DECL_OVERRIDE;
+
+private slots:
+    void handleUDevNotification();
+
+private:
+    bool checkDeviceType(struct udev_device *dev);
+
+    void startWatching();
+    void stopWatching();
+
+    struct udev *m_udev;
+    struct udev_monitor *m_udevMonitor;
+    int m_udevMonitorFileDescriptor;
+    QSocketNotifier *m_udevSocketNotifier;
+};
+
+QT_END_NAMESPACE
+
+#endif // QDEVICEDISCOVERY_UDEV_H