Disentangle QIODevice dependencies

Move the QIODevice::OpenMode enum into a base class, so that
we can remove the full QIODevice (and thus QObject) dependency
from qdatastream.h and qtextstream.h.

This is required so that we can include QDataStream in qmetatype.h
without getting circular dependencies.

As a nice side effect, QDataStream and QTextStream can now inherit
QIODeviceBase and provide the OpenMode enum directly in their
class scope.

Change-Id: Ifa68b7b1d8d95687ed032f6c9206f92e63bfacdf
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@qt.io>

examples/widgets/itemviews/puzzle/piecesmodel.cpp

@@ -132,7 +132,7 @@ QMimeData *PiecesModel::mimeData(const QModelIndexList &indexes) const
     QMimeData *mimeData = new QMimeData();
     QByteArray encodedData;
 
-    QDataStream stream(&encodedData, QIODevice::WriteOnly);
+    QDataStream stream(&encodedData, QDataStream::WriteOnly);
 
     for (const QModelIndex &index : indexes) {
         if (index.isValid()) {
@@ -170,7 +170,7 @@ bool PiecesModel::dropMimeData(const QMimeData *data, Qt::DropAction action,
     }
 
     QByteArray encodedData = data->data("image/x-puzzle-piece");
-    QDataStream stream(&encodedData, QIODevice::ReadOnly);
+    QDataStream stream(&encodedData, QDataStream::ReadOnly);
 
     while (!stream.atEnd()) {
         QPixmap pixmap;

qmake/CMakeLists.txt

@@ -61,6 +61,7 @@ qt_add_tool(${target_name}
         ../src/corelib/io/qfilesystementry.cpp
         ../src/corelib/io/qfsfileengine.cpp
         ../src/corelib/io/qfsfileengine_iterator.cpp
+        ../src/corelib/io/qiodevicebase.h
         ../src/corelib/io/qiodevice.cpp ../src/corelib/io/qiodevice.h
         ../src/corelib/io/qsettings.cpp
         ../src/corelib/io/qtemporaryfile.cpp ../src/corelib/io/qtemporaryfile.h

src/corelib/CMakeLists.txt

@@ -71,6 +71,7 @@ qt_add_module(Core
         io/qfilesystemmetadata_p.h
         io/qfsfileengine.cpp io/qfsfileengine_p.h
         io/qfsfileengine_iterator.cpp io/qfsfileengine_iterator_p.h
+        io/qiodevicebase.h
         io/qiodevice.cpp io/qiodevice.h io/qiodevice_p.h
         io/qipaddress.cpp io/qipaddress_p.h
         io/qlockfile.cpp io/qlockfile.h io/qlockfile_p.h

src/corelib/io/io.pri

@@ -15,6 +15,7 @@ HEADERS +=  \
         io/qfileinfo.h \
         io/qfileinfo_p.h \
         io/qipaddress_p.h \
+        io/qiodevicebase.h \
         io/qiodevice.h \
         io/qiodevice_p.h \
         io/qlockfile.h \

src/corelib/io/qdebug.h

@@ -60,7 +60,7 @@
 QT_BEGIN_NAMESPACE
 
 
-class Q_CORE_EXPORT QDebug
+class Q_CORE_EXPORT QDebug : public QIODeviceBase
 {
     friend class QMessageLogger;
     friend class QDebugStateSaver;
@@ -70,9 +70,9 @@ class Q_CORE_EXPORT QDebug
 
         Stream(QIODevice *device) : ts(device), ref(1), type(QtDebugMsg),
             space(true), message_output(false), flags(DefaultVerbosity << VerbosityShift) {}
-        Stream(QString *string) : ts(string, QIODevice::WriteOnly), ref(1), type(QtDebugMsg),
+        Stream(QString *string) : ts(string, WriteOnly), ref(1), type(QtDebugMsg),
             space(true), message_output(false), flags(DefaultVerbosity << VerbosityShift) {}
-        Stream(QtMsgType t) : ts(&buffer, QIODevice::WriteOnly), ref(1), type(t),
+        Stream(QtMsgType t) : ts(&buffer, WriteOnly), ref(1), type(t),
             space(true), message_output(true), flags(DefaultVerbosity << VerbosityShift) {}
         QTextStream ts;
         QString buffer;

src/corelib/io/qiodevice.cpp

@@ -305,7 +305,7 @@ QIODevicePrivate::~QIODevicePrivate()
 */
 
 /*!
-    \enum QIODevice::OpenModeFlag
+    \enum QIODeviceBase::OpenModeFlag
 
     This enum is used with open() to describe the mode in which a device
     is opened. It is also returned by openMode().

src/corelib/io/qiodevice.h

@@ -1,6 +1,6 @@
 /****************************************************************************
 **
-** Copyright (C) 2016 The Qt Company Ltd.
+** Copyright (C) 2020 The Qt Company Ltd.
 ** Contact: https://www.qt.io/licensing/
 **
 ** This file is part of the QtCore module of the Qt Toolkit.
@@ -41,6 +41,7 @@
 #define QIODEVICE_H
 
 #include <QtCore/qglobal.h>
+#include <QtCore/qiodevicebase.h>
 #ifndef QT_NO_QOBJECT
 #include <QtCore/qobject.h>
 #else
@@ -61,27 +62,16 @@ class QIODevicePrivate;
 
 class Q_CORE_EXPORT QIODevice
 #ifndef QT_NO_QOBJECT
-    : public QObject
+    : public QObject,
+#else
+    :
 #endif
+      public QIODeviceBase
 {
 #ifndef QT_NO_QOBJECT
     Q_OBJECT
 #endif
 public:
-    enum OpenModeFlag {
-        NotOpen = 0x0000,
-        ReadOnly = 0x0001,
-        WriteOnly = 0x0002,
-        ReadWrite = ReadOnly | WriteOnly,
-        Append = 0x0004,
-        Truncate = 0x0008,
-        Text = 0x0010,
-        Unbuffered = 0x0020,
-        NewOnly = 0x0040,
-        ExistingOnly = 0x0080
-    };
-    Q_DECLARE_FLAGS(OpenMode, OpenModeFlag)
-
     QIODevice();
 #ifndef QT_NO_QOBJECT
     explicit QIODevice(QObject *parent);

src/corelib/io/qiodevicebase.h

@@ -0,0 +1,67 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore 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.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QIODEVICEBASE_H
+#define QIODEVICEBASE_H
+
+#include <QtCore/qglobal.h>
+
+QT_BEGIN_NAMESPACE
+
+class QIODeviceBase
+{
+public:
+    enum OpenModeFlag {
+        NotOpen = 0x0000,
+        ReadOnly = 0x0001,
+        WriteOnly = 0x0002,
+        ReadWrite = ReadOnly | WriteOnly,
+        Append = 0x0004,
+        Truncate = 0x0008,
+        Text = 0x0010,
+        Unbuffered = 0x0020,
+        NewOnly = 0x0040,
+        ExistingOnly = 0x0080
+    };
+    Q_DECLARE_FLAGS(OpenMode, OpenModeFlag)
+};
+
+QT_END_NAMESPACE
+
+#endif // QIODEVICEBASE_H

src/corelib/itemmodels/qabstractitemmodel.cpp

@@ -1919,7 +1919,7 @@ QMimeData *QAbstractItemModel::mimeData(const QModelIndexList &indexes) const
     QMimeData *data = new QMimeData();
     QString format = types.at(0);
     QByteArray encoded;
-    QDataStream stream(&encoded, QIODevice::WriteOnly);
+    QDataStream stream(&encoded, QDataStream::WriteOnly);
     encodeData(indexes, stream);
     data->setData(format, encoded);
     return data;
@@ -2007,7 +2007,7 @@ bool QAbstractItemModel::dropMimeData(const QMimeData *data, Qt::DropAction acti
         column = 0;
     // decode and insert
     QByteArray encoded = data->data(format);
-    QDataStream stream(&encoded, QIODevice::ReadOnly);
+    QDataStream stream(&encoded, QDataStream::ReadOnly);
     return decodeData(row, column, parent, stream);
 }
 
@@ -3730,7 +3730,7 @@ bool QAbstractTableModel::dropMimeData(const QMimeData *data, Qt::DropAction act
         return false;
 
     QByteArray encoded = data->data(format);
-    QDataStream stream(&encoded, QIODevice::ReadOnly);
+    QDataStream stream(&encoded, QDataStream::ReadOnly);
 
     // if the drop is on an item, replace the data in the items
     if (parent.isValid() && row == -1 && column == -1) {
@@ -3781,7 +3781,7 @@ bool QAbstractListModel::dropMimeData(const QMimeData *data, Qt::DropAction acti
         return false;
 
     QByteArray encoded = data->data(format);
-    QDataStream stream(&encoded, QIODevice::ReadOnly);
+    QDataStream stream(&encoded, QDataStream::ReadOnly);
 
     // if the drop is on an item, replace the data in the items
     if (parent.isValid() && row == -1 && column == -1) {

src/corelib/kernel/qmetatype.h

@@ -47,6 +47,7 @@
 #include <QtCore/qbytearray.h>
 #include <QtCore/qvarlengtharray.h>
 #include <QtCore/qrefcount.h>
+#include <QtCore/qdatastream.h>
 #ifndef QT_NO_QOBJECT
 #include <QtCore/qobjectdefs.h>
 #endif

src/corelib/serialization/qcborstreamreader.cpp

@@ -45,6 +45,7 @@
 #include <private/qbytearray_p.h>
 #include <private/qnumeric_p.h>
 #include <private/qstringconverter_p.h>
+#include <qiodevice.h>
 #include <qdebug.h>
 #include <qstack.h>
 

src/corelib/serialization/qdatastream.cpp

@@ -302,7 +302,7 @@ QDataStream::QDataStream(QIODevice *d)
 }
 
 /*!
-    \fn QDataStream::QDataStream(QByteArray *a, QIODevice::OpenMode mode)
+    \fn QDataStream::QDataStream(QByteArray *a, OpenMode mode)
 
     Constructs a data stream that operates on a byte array, \a a. The
     \a mode describes how the device is to be used.
@@ -314,7 +314,7 @@ QDataStream::QDataStream(QIODevice *d)
     is created to wrap the byte array.
 */
 
-QDataStream::QDataStream(QByteArray *a, QIODevice::OpenMode flags)
+QDataStream::QDataStream(QByteArray *a, OpenMode flags)
 {
     QBuffer *buf = new QBuffer(a);
 #ifndef QT_NO_QOBJECT
@@ -755,6 +755,14 @@ void QDataStream::abortTransaction()
     dev->commitTransaction();
 }
 
+/*!
+   \internal
+*/
+bool QDataStream::isDeviceTransactionStarted() const
+{
+   return dev && dev->isTransactionStarted();
+}
+
 /*****************************************************************************
   QDataStream read functions
  *****************************************************************************/

src/corelib/serialization/qdatastream.h

@@ -41,8 +41,7 @@
 #define QDATASTREAM_H
 
 #include <QtCore/qscopedpointer.h>
-#include <QtCore/qiodevice.h>
-#include <QtCore/qpair.h>
+#include <QtCore/qiodevicebase.h>
 #include <QtCore/qcontainerfwd.h>
 
 #ifdef Status
@@ -60,7 +59,7 @@ class QDataStreamPrivate;
 namespace QtPrivate {
 class StreamStateSaver;
 }
-class Q_CORE_EXPORT QDataStream
+class Q_CORE_EXPORT QDataStream : public QIODeviceBase
 {
 public:
     enum Version {
@@ -122,7 +121,7 @@ public:
 
     QDataStream();
     explicit QDataStream(QIODevice *);
-    QDataStream(QByteArray *, QIODevice::OpenMode flags);
+    QDataStream(QByteArray *, OpenMode flags);
     QDataStream(const QByteArray &);
     ~QDataStream();
 
@@ -199,6 +198,7 @@ public:
     void rollbackTransaction();
     void abortTransaction();
 
+    bool isDeviceTransactionStarted() const;
 private:
     Q_DISABLE_COPY(QDataStream)
 
@@ -222,7 +222,7 @@ class StreamStateSaver
 public:
     inline StreamStateSaver(QDataStream *s) : stream(s), oldStatus(s->status())
     {
-        if (!stream->dev || !stream->dev->isTransactionStarted())
+        if (!stream->isDeviceTransactionStarted())
             stream->resetStatus();
     }
     inline ~StreamStateSaver()

src/corelib/serialization/qtextstream.cpp

@@ -368,7 +368,7 @@ void QTextStreamPrivate::reset()
     deleteDevice = false;
     string = nullptr;
     stringOffset = 0;
-    stringOpenMode = QIODevice::NotOpen;
+    stringOpenMode = QTextStream::NotOpen;
 
     readBufferOffset = 0;
     readBufferStartDevicePos = 0;
@@ -983,7 +983,7 @@ QTextStream::QTextStream(QIODevice *device)
     Constructs a QTextStream that operates on \a string, using \a
     openMode to define the open mode.
 */
-QTextStream::QTextStream(QString *string, QIODevice::OpenMode openMode)
+QTextStream::QTextStream(QString *string, OpenMode openMode)
     : d_ptr(new QTextStreamPrivate(this))
 {
 #if defined (QTEXTSTREAM_DEBUG)
@@ -1001,7 +1001,7 @@ QTextStream::QTextStream(QString *string, QIODevice::OpenMode openMode)
     openMode to define the open mode. Internally, the array is wrapped
     by a QBuffer.
 */
-QTextStream::QTextStream(QByteArray *array, QIODevice::OpenMode openMode)
+QTextStream::QTextStream(QByteArray *array, OpenMode openMode)
     : d_ptr(new QTextStreamPrivate(this))
 {
 #if defined (QTEXTSTREAM_DEBUG)
@@ -1028,7 +1028,7 @@ QTextStream::QTextStream(QByteArray *array, QIODevice::OpenMode openMode)
 
     \snippet code/src_corelib_io_qtextstream.cpp 3
 */
-QTextStream::QTextStream(const QByteArray &array, QIODevice::OpenMode openMode)
+QTextStream::QTextStream(const QByteArray &array, OpenMode openMode)
     : d_ptr(new QTextStreamPrivate(this))
 {
 #if defined (QTEXTSTREAM_DEBUG)
@@ -1059,7 +1059,7 @@ QTextStream::QTextStream(const QByteArray &array, QIODevice::OpenMode openMode)
     \snippet code/src_corelib_io_qtextstream.cpp 4
 */
 
-QTextStream::QTextStream(FILE *fileHandle, QIODevice::OpenMode openMode)
+QTextStream::QTextStream(FILE *fileHandle, OpenMode openMode)
     : d_ptr(new QTextStreamPrivate(this))
 {
 #if defined (QTEXTSTREAM_DEBUG)
@@ -1272,7 +1272,7 @@ QIODevice *QTextStream::device() const
 
     \sa string(), setDevice()
 */
-void QTextStream::setString(QString *string, QIODevice::OpenMode openMode)
+void QTextStream::setString(QString *string, OpenMode openMode)
 {
     Q_D(QTextStream);
     flush();

src/corelib/serialization/qtextstream.h

@@ -40,10 +40,9 @@
 #ifndef QTEXTSTREAM_H
 #define QTEXTSTREAM_H
 
-#include <QtCore/qiodevice.h>
+#include <QtCore/qiodevicebase.h>
 #include <QtCore/qstring.h>
 #include <QtCore/qchar.h>
-#include <QtCore/qlocale.h>
 #include <QtCore/qscopedpointer.h>
 #include <QtCore/qstringconverter.h>
 
@@ -55,8 +54,11 @@
 
 QT_BEGIN_NAMESPACE
 
+class QIODevice;
+class QLocale;
+
 class QTextStreamPrivate;
-class Q_CORE_EXPORT QTextStream                                // text stream class
+class Q_CORE_EXPORT QTextStream : public QIODeviceBase
 {
     Q_DECLARE_PRIVATE(QTextStream)
 
@@ -89,10 +91,10 @@ public:
 
     QTextStream();
     explicit QTextStream(QIODevice *device);
-    explicit QTextStream(FILE *fileHandle, QIODevice::OpenMode openMode = QIODevice::ReadWrite);
-    explicit QTextStream(QString *string, QIODevice::OpenMode openMode = QIODevice::ReadWrite);
-    explicit QTextStream(QByteArray *array, QIODevice::OpenMode openMode = QIODevice::ReadWrite);
-    explicit QTextStream(const QByteArray &array, QIODevice::OpenMode openMode = QIODevice::ReadOnly);
+    explicit QTextStream(FILE *fileHandle, OpenMode openMode = ReadWrite);
+    explicit QTextStream(QString *string, OpenMode openMode = ReadWrite);
+    explicit QTextStream(QByteArray *array, OpenMode openMode = ReadWrite);
+    explicit QTextStream(const QByteArray &array, OpenMode openMode = ReadOnly);
     virtual ~QTextStream();
 
     void setEncoding(QStringConverter::Encoding encoding);
@@ -108,7 +110,7 @@ public:
     void setDevice(QIODevice *device);
     QIODevice *device() const;
 
-    void setString(QString *string, QIODevice::OpenMode openMode = QIODevice::ReadWrite);
+    void setString(QString *string, OpenMode openMode = ReadWrite);
     QString *string() const;
 
     Status status() const;

src/corelib/serialization/qtextstream_p.h

@@ -53,6 +53,8 @@
 //
 
 #include <QtCore/private/qglobal_p.h>
+#include "qiodevice.h"
+#include "qlocale.h"
 #include "qtextstream.h"
 
 QT_BEGIN_NAMESPACE

src/gui/itemmodels/qstandarditemmodel.cpp

@@ -47,6 +47,7 @@
 #include <QtCore/qstringlist.h>
 #include <QtCore/qbitarray.h>
 #include <QtCore/qmimedata.h>
+#include <QtCore/qiodevice.h>
 #include <private/qduplicatetracker_p.h>
 #include <private/qstandarditemmodel_p.h>
 #include <qdebug.h>

src/gui/rhi/qrhiprofiler.cpp

@@ -36,6 +36,7 @@
 
 #include "qrhiprofiler_p_p.h"
 #include "qrhi_p_p.h"
+#include <QtCore/qiodevice.h>
 
 QT_BEGIN_NAMESPACE
 

src/gui/util/qktxhandler.cpp

@@ -41,6 +41,7 @@
 #include "qtexturefiledata_p.h"
 #include <QtEndian>
 #include <QSize>
+#include <QtCore/qiodevice.h>
 
 //#define KTX_DEBUG
 #ifdef KTX_DEBUG

src/network/ssl/qasn1element.cpp

@@ -186,7 +186,7 @@ QAsn1Element QAsn1Element::fromVector(const QList<QAsn1Element> &items)
 {
     QAsn1Element seq;
     seq.mType = SequenceType;
-    QDataStream stream(&seq.mValue, QIODevice::WriteOnly);
+    QDataStream stream(&seq.mValue, QDataStream::WriteOnly);
     for (auto it = items.cbegin(), end = items.cend(); it != end; ++it)
         it->write(stream);
     return seq;

src/tools/qlalr/lalr.cpp

@@ -42,13 +42,13 @@
 QT_BEGIN_NAMESPACE
 QTextStream &qerr()
 {
-    static QTextStream result(stderr, QIODevice::WriteOnly);
+    static QTextStream result(stderr, QTextStream::WriteOnly);
     return result;
 }
 
 QTextStream &qout()
 {
-    static QTextStream result(stdout, QIODevice::WriteOnly);
+    static QTextStream result(stdout, QTextStream::WriteOnly);
     return result;
 }
 QT_END_NAMESPACE

src/tools/qlalr/lalr.h

@@ -39,6 +39,7 @@
 #include <algorithm>
 #include <functional>
 #include <set>
+#include <list>
 
 class Rule;
 class State;

src/xml/dom/qdom_p.h

@@ -46,6 +46,7 @@
 #include <qstring.h>
 #include <qlist.h>
 #include <qxml.h>
+#include <qshareddata.h>
 
 QT_BEGIN_NAMESPACE
 

src/xml/sax/qxml_p.h

@@ -42,6 +42,7 @@
 
 #include <qstack.h>
 #include <qmap.h>
+#include <qhash.h>
 #include <qxml.h>
 
 #include <stack>