New class QTemporaryDir.

As discussed on qt5-feedback / development lists.

Change-Id: If1733369d12daa29054776ec2cbd78e63679768e
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@nokia.com>

doc/src/snippets/code/src_corelib_io_qtemporarydir.cpp

@@ -0,0 +1,53 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
+**     the names of its contributors may be used to endorse or promote
+**     products derived from this software without specific prior written
+**     permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+{
+//! [0]
+    // Within a function/method...
+
+    QTemporaryDir dir;
+    if (dir.isValid()) {
+        // dir.path() returns the unique directory path
+    }
+
+    // The QTemporaryDir destructor removes the temporary directory
+    // as it goes out of scope.
+//! [0]
+}

src/corelib/io/io.pri

@@ -20,6 +20,7 @@ HEADERS +=  \
         io/qprocess.h \
         io/qprocess_p.h \
         io/qtextstream.h \
+        io/qtemporarydir.h \
         io/qtemporaryfile.h \
         io/qresource_p.h \
         io/qresource_iterator_p.h \
@@ -54,6 +55,7 @@ SOURCES += \
         io/qnoncontiguousbytedevice.cpp \
         io/qprocess.cpp \
         io/qtextstream.cpp \
+        io/qtemporarydir.cpp \
         io/qtemporaryfile.cpp \
         io/qresource.cpp \
         io/qresource_iterator.cpp \

src/corelib/io/qdir_p.h

@@ -67,11 +67,11 @@ public:
 
     static inline QStringList splitFilters(const QString &nameFilter, QChar sep = 0);
 
-    inline void setPath(const QString &path);
+    void setPath(const QString &path);
 
-    inline void clearFileLists();
+    void clearFileLists();
 
-    inline void resolveAbsoluteEntry() const;
+    void resolveAbsoluteEntry() const;
 
     QStringList nameFilters;
     QDir::SortFlags sort;

src/corelib/io/qtemporarydir.cpp

@@ -0,0 +1,258 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module 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 "qtemporarydir.h"
+
+#ifndef QT_NO_TEMPORARYFILE
+
+#include "qdiriterator.h"
+#include "qplatformdefs.h"
+#include "private/qdir_p.h"
+#include <QDebug>
+
+#if defined(QT_BUILD_CORE_LIB)
+#include "qcoreapplication.h"
+#endif
+
+#include <stdlib.h> // mkdtemp
+#ifdef Q_OS_WIN
+#include <windows.h>
+#include <private/qfsfileengine_p.h>
+#endif
+
+QT_BEGIN_NAMESPACE
+
+//************* QTemporaryDirPrivate
+class QTemporaryDirPrivate
+{
+public:
+    QTemporaryDirPrivate();
+    ~QTemporaryDirPrivate();
+
+    QString defaultTemplateName() const;
+    void create(const QString &templateName);
+
+    QString path;
+    bool autoRemove;
+    bool success;
+};
+
+QTemporaryDirPrivate::QTemporaryDirPrivate()
+    : autoRemove(true),
+      success(false)
+{
+}
+
+QTemporaryDirPrivate::~QTemporaryDirPrivate()
+{
+}
+
+QString QTemporaryDirPrivate::defaultTemplateName() const
+{
+    QString baseName;
+#if defined(QT_BUILD_CORE_LIB)
+    baseName = QCoreApplication::applicationName();
+    if (baseName.isEmpty())
+#endif
+        baseName = QLatin1String("qt_temp");
+
+    return QDir::tempPath() + QLatin1Char('/') + baseName + QLatin1String("-XXXXXX");
+}
+
+void QTemporaryDirPrivate::create(const QString &templateName)
+{
+#ifdef Q_OS_WIN
+    QString buffer = templateName;
+    // Windows' mktemp believes 26 temp files per process ought to be enough for everyone (!)
+    // Let's add a few random chars then, before the XXXXXX template.
+    for (int i = 0 ; i < 4 ; ++i)
+        buffer += QChar((qrand() & 0xffff) % (26) + 'A');
+    if (!buffer.endsWith(QLatin1String("XXXXXX")))
+        buffer += QLatin1String("XXXXXX");
+    QFileSystemEntry baseEntry(buffer);
+    QFileSystemEntry::NativePath basePath = baseEntry.nativeFilePath();
+    wchar_t* array = (wchar_t*)basePath.utf16();
+    if (_wmktemp(array) && ::CreateDirectory(array, 0)) {
+        success = true;
+        QFileSystemEntry entry(QString::fromWCharArray(array), QFileSystemEntry::FromNativePath());
+        path = entry.filePath();
+    }
+#else
+    QByteArray buffer = QFile::encodeName(templateName);
+    if (!buffer.endsWith("XXXXXX"))
+        buffer += "XXXXXX";
+    if (mkdtemp(buffer.data())) { // modifies buffer
+        success = true;
+        path = QFile::decodeName(buffer.constData());
+    }
+#endif
+}
+
+//************* QTemporaryDir
+
+/*!
+    \class QTemporaryDir
+    \reentrant
+    \brief The QTemporaryDir class creates a unique directory for temporary use.
+
+    \ingroup io
+
+
+    QTemporaryDir is used to create unique temporary dirs safely.
+    The dir itself is created by the constructor. The name of the
+    temporary directory is guaranteed to be unique (i.e., you are
+    guaranteed to not overwrite an existing dir), and the directory will
+    subsequently be removed upon destruction of the QTemporaryDir
+    object. The directory name is either auto-generated, or created based
+    on a template, which is passed to QTemporaryDir's constructor.
+
+    Example:
+
+    \snippet doc/src/snippets/code/src_corelib_io_qtemporarydir.cpp 0
+
+    It is very important to test that the temporary directory could be
+    created, using isValid(). Do not use exists(), since a default-constructed
+    QDir represents the current directory, which exists.
+
+    The path to the temporary dir can be found by calling path().
+
+    A temporary directory will have some static part of the name and some
+    part that is calculated to be unique. The default path will be
+    determined from QCoreApplication::applicationName() (otherwise \c qt_temp) and will
+    be placed into the temporary path as returned by QDir::tempPath().
+    If you specify your own path, a relative path will not be placed in the
+    temporary directory by default, but be relative to the current working directory.
+    In all cases, a random string will be appended to the path in order to make it unique.
+
+    \sa QDir::tempPath(), QDir, QTemporaryFile
+*/
+
+QTemporaryDir::QTemporaryDir()
+    : d_ptr(new QTemporaryDirPrivate)
+{
+    d_ptr->create(d_ptr->defaultTemplateName());
+}
+
+QTemporaryDir::QTemporaryDir(const QString &templateName)
+    : d_ptr(new QTemporaryDirPrivate)
+{
+    if (templateName.isEmpty())
+        d_ptr->create(d_ptr->defaultTemplateName());
+    else
+        d_ptr->create(templateName);
+}
+
+/*!
+    Destroys the temporary directory object.
+    If auto remove mode was set, it will automatically delete the directory
+    including all its contents.
+
+    \sa autoRemove()
+*/
+QTemporaryDir::~QTemporaryDir()
+{
+    if (d_ptr->success && d_ptr->autoRemove)
+        remove();
+    delete d_ptr;
+}
+
+/*!
+   Returns true if the QTemporaryDir was created successfully.
+*/
+bool QTemporaryDir::isValid() const
+{
+    return d_ptr->success;
+}
+
+/*!
+   Returns the path to the temporary directory.
+   Empty if the QTemporaryDir could not be created.
+*/
+QString QTemporaryDir::path() const
+{
+    return d_ptr->path;
+}
+
+/*!
+   Returns true if the QTemporaryDir is in auto remove
+   mode. Auto-remove mode will automatically delete the directory from
+   disk upon destruction. This makes it very easy to create your
+   QTemporaryDir object on the stack, fill it with files, do something with
+   the files, and finally on function return it will automatically clean up
+   after itself.
+
+   Auto-remove is on by default.
+
+   \sa setAutoRemove(), remove()
+*/
+bool QTemporaryDir::autoRemove() const
+{
+    return d_ptr->autoRemove;
+}
+
+/*!
+    Sets the QTemporaryDir into auto-remove mode if \a b is true.
+
+    Auto-remove is on by default.
+
+    \sa autoRemove(), remove()
+*/
+void QTemporaryDir::setAutoRemove(bool b)
+{
+    d_ptr->autoRemove = b;
+}
+
+/*!
+    Removes the temporary directory, including all its contents.
+*/
+bool QTemporaryDir::remove()
+{
+    if (!d_ptr->success)
+        return false;
+    Q_ASSERT(!path().isEmpty());
+    Q_ASSERT(path() != QLatin1String("."));
+
+    return QDir(path()).removeRecursively();
+}
+
+QT_END_NAMESPACE
+
+#endif // QT_NO_TEMPORARYFILE

src/corelib/io/qtemporarydir.h

@@ -0,0 +1,84 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module 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 QTEMPORARYDIR_H
+#define QTEMPORARYDIR_H
+
+#include <QtCore/qdir.h>
+
+QT_BEGIN_HEADER
+
+QT_BEGIN_NAMESPACE
+
+QT_MODULE(Core)
+
+#ifndef QT_NO_TEMPORARYFILE
+
+class QTemporaryDirPrivate;
+
+class Q_CORE_EXPORT QTemporaryDir
+{
+public:
+    QTemporaryDir();
+    explicit QTemporaryDir(const QString &templateName);
+    ~QTemporaryDir();
+
+    bool isValid() const;
+
+    bool autoRemove() const;
+    void setAutoRemove(bool b);
+    bool remove();
+
+    QString path() const;
+
+private:
+    QTemporaryDirPrivate* const d_ptr;
+
+    Q_DISABLE_COPY(QTemporaryDir)
+};
+
+#endif // QT_NO_TEMPORARYFILE
+
+QT_END_NAMESPACE
+
+QT_END_HEADER
+
+#endif // QTEMPORARYDIR_H

tests/auto/corelib/io/io.pro

@@ -16,6 +16,7 @@ SUBDIRS=\
     qresourceengine \
     qsettings \
     qstandardpaths \
+    qtemporarydir \
     qtemporaryfile \
     qtextstream \
     qurl \

tests/auto/corelib/io/qtemporarydir/qtemporarydir.pro

@@ -0,0 +1,7 @@
+CONFIG += testcase
+TARGET = tst_qtemporarydir
+SOURCES       += tst_qtemporarydir.cpp
+
+QT = core testlib
+
+CONFIG += parallel_test

tests/auto/corelib/io/qtemporarydir/tst_qtemporarydir.cpp

@@ -0,0 +1,471 @@
+/****************************************************************************
+**
+** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the test suite 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 <QtTest/QtTest>
+#include <qcoreapplication.h>
+#include <qstring.h>
+#include <qtemporarydir.h>
+#include <qfile.h>
+#include <qdir.h>
+#include <qset.h>
+#ifdef Q_OS_WIN
+# include <windows.h>
+#endif
+
+//TESTED_CLASS=QTemporaryDir
+//TESTED_FILES=qtemporarydir.cpp
+
+class tst_QTemporaryDir : public QObject
+{
+    Q_OBJECT
+public:
+    tst_QTemporaryDir();
+    virtual ~tst_QTemporaryDir();
+public slots:
+    void init();
+    void cleanup();
+
+    void initTestCase();
+    void cleanupTestCase();
+
+private slots:
+    void construction();
+    void fileTemplate();
+    void fileTemplate_data();
+    void getSetCheck();
+    void fileName();
+    void autoRemove();
+    void nonWritableCurrentDir();
+    void openOnRootDrives();
+    void stressTest();
+    void rename();
+    void autoRemoveAfterFailedRename();
+
+    void QTBUG_4796_data();
+    void QTBUG_4796();
+
+public:
+};
+
+void tst_QTemporaryDir::initTestCase()
+{
+    QVERIFY(QDir("test-XXXXXX").exists() || QDir().mkdir("test-XXXXXX"));
+    QCoreApplication::setApplicationName("tst_qtemporarydir");
+}
+
+void tst_QTemporaryDir::cleanupTestCase()
+{
+    QVERIFY(QDir().rmdir("test-XXXXXX"));
+}
+
+void tst_QTemporaryDir::construction()
+{
+    QTemporaryDir dir;
+    QString tmp = QDir::tempPath();
+    QCOMPARE(dir.path().left(tmp.size()), tmp);
+    QVERIFY(dir.path().contains("tst_qtemporarydir"));
+    QVERIFY(QFileInfo(dir.path()).isDir());
+}
+
+// Testing get/set functions
+void tst_QTemporaryDir::getSetCheck()
+{
+    QTemporaryDir obj1;
+    // bool QTemporaryDir::autoRemove()
+    // void QTemporaryDir::setAutoRemove(bool)
+    obj1.setAutoRemove(false);
+    QCOMPARE(false, obj1.autoRemove());
+    obj1.setAutoRemove(true);
+    QCOMPARE(true, obj1.autoRemove());
+}
+
+tst_QTemporaryDir::tst_QTemporaryDir()
+{
+}
+
+tst_QTemporaryDir::~tst_QTemporaryDir()
+{
+
+}
+
+void tst_QTemporaryDir::init()
+{
+}
+
+void tst_QTemporaryDir::cleanup()
+{
+}
+
+void tst_QTemporaryDir::fileTemplate_data()
+{
+    QTest::addColumn<QString>("constructorTemplate");
+    QTest::addColumn<QString>("prefix");
+
+    QTest::newRow("constructor default") << "" << "tst_qtemporarydir-";
+
+    QTest::newRow("constructor with xxx sufix") << "qt_XXXXXXxxx" << "qt_XXXXXXxxx";
+    QTest::newRow("constructor with xXx sufix") << "qt_XXXXXXxXx" << "qt_XXXXXXxXx";
+    QTest::newRow("constructor with no suffix") << "qt_XXXXXX" << "qt_";
+    QTest::newRow("constructor with >6 X's, no suffix") << "qt_XXXXXXXXXX" << "qt_XXXX";
+    QTest::newRow("constructor with XXXX suffix") << "qt_XXXXXX_XXXX" << "qt_";
+    QTest::newRow("constructor with XXXX prefix") << "qt_XXXX" << "qt_XXXX";
+    QTest::newRow("constructor with XXXXX prefix") << "qt_XXXXX" << "qt_XXXXX";
+}
+
+void tst_QTemporaryDir::fileTemplate()
+{
+    QFETCH(QString, constructorTemplate);
+    QFETCH(QString, prefix);
+
+    QTemporaryDir tempDir(constructorTemplate);
+
+    QVERIFY(tempDir.isValid());
+
+    QString dirName = QDir(tempDir.path()).dirName();
+    if (prefix.length())
+        QCOMPARE(dirName.left(prefix.length()), prefix);
+}
+
+
+/*
+    This tests whether the temporary dir really gets placed in QDir::tempPath
+*/
+void tst_QTemporaryDir::fileName()
+{
+    // Get QDir::tempPath and make an absolute path.
+    QString tempPath = QDir::tempPath();
+    QString absoluteTempPath = QDir(tempPath).absolutePath();
+    QTemporaryDir dir;
+    dir.setAutoRemove(true);
+    QString fileName = dir.path();
+    QVERIFY2(fileName.contains("/tst_qtemporarydir-"), qPrintable(fileName));
+    QVERIFY(QFile::exists(fileName));
+    // Get path to the temp dir, without the file name.
+    QString absoluteFilePath = QFileInfo(fileName).absolutePath();
+#if defined(Q_OS_WIN)
+    absoluteFilePath = absoluteFilePath.toLower();
+    absoluteTempPath = absoluteTempPath.toLower();
+#endif
+    QCOMPARE(absoluteFilePath, absoluteTempPath);
+}
+
+void tst_QTemporaryDir::autoRemove()
+{
+    // Test auto remove
+    QString dirName;
+    {
+        QTemporaryDir dir("tempXXXXXX");
+        dir.setAutoRemove(true);
+        QVERIFY(dir.isValid());
+        dirName = dir.path();
+    }
+#ifdef Q_OS_WIN
+    // Windows seems unreliable here: sometimes it says the directory still exists,
+    // immediately after we deleted it.
+    QTRY_VERIFY(!QFile::exists(dirName));
+#else
+    QVERIFY(!QFile::exists(dirName));
+#endif
+
+    // Test if disabling auto remove works.
+    {
+        QTemporaryDir dir("tempXXXXXX");
+        dir.setAutoRemove(false);
+        QVERIFY(dir.isValid());
+        dirName = dir.path();
+    }
+    QVERIFY(QFile::exists(dirName));
+    QVERIFY(QDir().rmdir(dirName));
+    QVERIFY(!QFile::exists(dirName));
+
+    // Do not explicitly call setAutoRemove (tests if it really is the default as documented)
+    {
+        QTemporaryDir dir("tempXXXXXX");
+        QVERIFY(dir.isValid());
+        dirName = dir.path();
+    }
+#ifdef Q_OS_WIN
+    QTRY_VERIFY(!QFile::exists(dirName));
+#else
+    QVERIFY(!QFile::exists(dirName));
+#endif
+
+    // Test autoremove with files and subdirs in the temp dir
+    {
+        QTemporaryDir tempDir("tempXXXXXX");
+        QVERIFY(tempDir.isValid());
+        dirName = tempDir.path();
+        QDir dir(dirName);
+        QVERIFY(dir.mkdir(QString::fromLatin1("dir1")));
+        QVERIFY(dir.mkdir(QString::fromLatin1("dir2")));
+        QVERIFY(dir.mkdir(QString::fromLatin1("dir2/nested")));
+        QFile file(dirName + "/dir1/file");
+        QVERIFY(file.open(QIODevice::WriteOnly));
+        QCOMPARE(file.write("Hello"), 5LL);
+    }
+#ifdef Q_OS_WIN
+    QTRY_VERIFY(!QFile::exists(dirName));
+#else
+    QVERIFY(!QFile::exists(dirName));
+#endif
+}
+
+void tst_QTemporaryDir::nonWritableCurrentDir()
+{
+#ifdef Q_OS_UNIX
+    QString cwd = QDir::currentPath();
+    QDir::setCurrent("/");
+    // QTemporaryDir("tempXXXXXX") is probably a bad idea in any app
+    // where the current dir could anything...
+    QString fileName;
+    QTemporaryDir dir("tempXXXXXX");
+    dir.setAutoRemove(true);
+    QVERIFY(!dir.isValid());
+    fileName = dir.path();
+    QDir::setCurrent(cwd);
+#endif
+}
+
+void tst_QTemporaryDir::openOnRootDrives()
+{
+#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
+    unsigned int lastErrorMode = SetErrorMode(SEM_FAILCRITICALERRORS);
+#endif
+    // If it's possible to create a dir in the root directory, it
+    // must be possible to create a temp dir there too.
+    foreach (const QFileInfo &driveInfo, QDir::drives()) {
+        QFile testFile(driveInfo.filePath() + "XXXXXX.txt");
+        if (testFile.open(QIODevice::ReadWrite)) {
+            testFile.remove();
+            QTemporaryDir dir(driveInfo.filePath() + "XXXXXX.txt");
+            dir.setAutoRemove(true);
+            QVERIFY(dir.isValid());
+        }
+    }
+#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
+    SetErrorMode(lastErrorMode);
+#endif
+}
+
+void tst_QTemporaryDir::stressTest()
+{
+    const int iterations = 1000;
+
+    QSet<QString> names;
+    for (int i = 0; i < iterations; ++i) {
+        QTemporaryDir dir;
+        dir.setAutoRemove(false);
+        QVERIFY2(dir.isValid(), qPrintable(QString::number(i)));
+        QVERIFY(!names.contains(dir.path()));
+        names.insert(dir.path());
+    }
+    for (QSet<QString>::const_iterator it = names.constBegin(); it != names.constEnd(); ++it)
+        QDir(*it).removeRecursively();
+}
+
+void tst_QTemporaryDir::rename()
+{
+    // This test checks what happens if the temporary dir is renamed.
+    // Then the autodelete feature can't possibly find it.
+
+    QDir dir;
+    QVERIFY(!dir.exists("temporary-dir.renamed"));
+
+    QString tempname;
+    {
+        QTemporaryDir tempDir(dir.filePath("temporary-dir.XXXXXX"));
+
+        QVERIFY(tempDir.isValid());
+        tempname = tempDir.path();
+
+        QVERIFY(QDir().rename(tempname, "temporary-dir.renamed"));
+        QVERIFY(!QDir(tempname).exists());
+        dir.setPath("temporary-dir.renamed");
+        QCOMPARE(dir.path(), QString("temporary-dir.renamed"));
+        QVERIFY(dir.exists());
+    }
+
+    // Auto-delete couldn't find it
+    QVERIFY(dir.exists());
+    // Clean up by hand
+    QVERIFY(dir.removeRecursively());
+    QVERIFY(!dir.exists());
+}
+
+void tst_QTemporaryDir::autoRemoveAfterFailedRename()
+{
+    struct CleanOnReturn
+    {
+        ~CleanOnReturn()
+        {
+            if (!tempName.isEmpty())
+                QVERIFY(QDir(tempName).removeRecursively());
+        }
+
+        void reset()
+        {
+            tempName.clear();
+        }
+
+        QString tempName;
+    };
+
+    CleanOnReturn cleaner;
+
+    {
+        QTemporaryDir dir;
+        QVERIFY(dir.isValid());
+        cleaner.tempName = dir.path();
+
+        QVERIFY(QFile::exists(cleaner.tempName));
+        QVERIFY(!QFileInfo("i-do-not-exist").isDir());
+        QVERIFY(!QDir().rename(cleaner.tempName, "i-do-not-exist/dir.txt"));
+        QVERIFY(QFile::exists(cleaner.tempName));
+    }
+
+    QVERIFY(!QFile::exists(cleaner.tempName));
+    cleaner.reset();
+}
+
+void tst_QTemporaryDir::QTBUG_4796_data()
+{
+    QTest::addColumn<QString>("prefix");
+    QTest::addColumn<QString>("suffix");
+    QTest::addColumn<bool>("openResult");
+
+    QString unicode = QString::fromUtf8("\xc3\xa5\xc3\xa6\xc3\xb8");
+
+    QTest::newRow("<empty>") << QString() << QString() << true;
+    QTest::newRow(".") << QString(".") << QString() << true;
+    QTest::newRow("..") << QString("..") << QString() << true;
+    QTest::newRow("blaXXXXXX") << QString("bla") << QString() << true;
+    QTest::newRow("does-not-exist/qt_temp.XXXXXX") << QString("does-not-exist/qt_temp") << QString() << false;
+    QTest::newRow("XXXXXX<unicode>") << QString() << unicode << true;
+    QTest::newRow("<unicode>XXXXXX") << unicode << QString() << true;
+}
+
+void tst_QTemporaryDir::QTBUG_4796()
+{
+    QVERIFY(QDir("test-XXXXXX").exists());
+
+    struct CleanOnReturn
+    {
+        ~CleanOnReturn()
+        {
+            foreach (const QString &tempName, tempNames)
+                QVERIFY(QDir(tempName).removeRecursively());
+        }
+
+        void reset()
+        {
+            tempNames.clear();
+        }
+
+        QStringList tempNames;
+    };
+
+    CleanOnReturn cleaner;
+
+    QFETCH(QString, prefix);
+    QFETCH(QString, suffix);
+    QFETCH(bool, openResult);
+
+    {
+        QString fileTemplate1 = prefix + QString("XX") + suffix;
+        QString fileTemplate2 = prefix + QString("XXXX") + suffix;
+        QString fileTemplate3 = prefix + QString("XXXXXX") + suffix;
+        QString fileTemplate4 = prefix + QString("XXXXXXXX") + suffix;
+
+        QTemporaryDir dir1(fileTemplate1);
+        QTemporaryDir dir2(fileTemplate2);
+        QTemporaryDir dir3(fileTemplate3);
+        QTemporaryDir dir4(fileTemplate4);
+        QTemporaryDir dir5("test-XXXXXX/" + fileTemplate1);
+        QTemporaryDir dir6("test-XXXXXX/" + fileTemplate3);
+
+        QCOMPARE(dir1.isValid(), openResult);
+        QCOMPARE(dir2.isValid(), openResult);
+        QCOMPARE(dir3.isValid(), openResult);
+        QCOMPARE(dir4.isValid(), openResult);
+        QCOMPARE(dir5.isValid(), openResult);
+        QCOMPARE(dir6.isValid(), openResult);
+
+        // make sure the dir exists under the *correct* name
+        if (openResult) {
+            cleaner.tempNames << dir1.path()
+                << dir2.path()
+                << dir3.path()
+                << dir4.path()
+                << dir5.path()
+                << dir6.path();
+
+            QDir currentDir;
+            QString fileName1 = currentDir.relativeFilePath(dir1.path());
+            QString fileName2 = currentDir.relativeFilePath(dir2.path());
+            QString fileName3 = currentDir.relativeFilePath(dir3.path());
+            QString fileName4 = currentDir.relativeFilePath(dir4.path());
+            QString fileName5 = currentDir.relativeFilePath(dir5.path());
+            QString fileName6 = currentDir.relativeFilePath(dir6.path());
+
+            QVERIFY(fileName1.startsWith(fileTemplate1));
+            QVERIFY(fileName2.startsWith(fileTemplate2));
+            QVERIFY(fileName5.startsWith("test-XXXXXX/" + fileTemplate1));
+            QVERIFY(fileName6.startsWith("test-XXXXXX/" + prefix));
+
+            if (!prefix.isEmpty()) {
+                QVERIFY(fileName3.startsWith(prefix));
+                QVERIFY(fileName4.startsWith(prefix));
+            }
+        }
+    }
+
+#ifdef Q_OS_WIN
+    QTest::qWait(20);
+#endif
+    foreach (const QString &tempName, cleaner.tempNames)
+        QVERIFY2(!QFile::exists(tempName), qPrintable(tempName));
+
+    cleaner.reset();
+}
+
+QTEST_MAIN(tst_QTemporaryDir)
+#include "tst_qtemporarydir.moc"