qfilesystemmodel.cpp

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#include "qfilesystemmodel_p.h"
#include "qfilesystemmodel.h"
#include <qlocale.h>
#include <qmimedata.h>
#include <qurl.h>
#include <qdebug.h>
#include <qmessagebox.h>
#include <qapplication.h>

#include <algorithm>

#ifdef Q_OS_WIN
#  include <QtCore/QVarLengthArray>
#  include <qt_windows.h>
#endif

QT_BEGIN_NAMESPACE

#ifndef QT_NO_FILESYSTEMMODEL

/*!
    \enum QFileSystemModel::Roles
    \value FileIconRole
    \value FilePathRole
    \value FileNameRole
    \value FilePermissions
*/

/*!
    \class QFileSystemModel
    \since 4.4

    \brief The QFileSystemModel class provides a data model for the local filesystem.

    \ingroup model-view
    \inmodule QtWidgets

    This class provides access to the local filesystem, providing functions
    for renaming and removing files and directories, and for creating new
    directories. In the simplest case, it can be used with a suitable display
    widget as part of a browser or filter.

    QFileSystemModel can be accessed using the standard interface provided by
    QAbstractItemModel, but it also provides some convenience functions that are
    specific to a directory model.
    The fileInfo(), isDir(), fileName() and filePath() functions provide information
    about the underlying files and directories related to items in the model.
    Directories can be created and removed using mkdir(), rmdir().

    \note QFileSystemModel requires an instance of a GUI application.

    \section1 Example Usage

    A directory model that displays the contents of a default directory
    is usually constructed with a parent object:

    \snippet shareddirmodel/main.cpp 2

    A tree view can be used to display the contents of the model

    \snippet shareddirmodel/main.cpp 4

    and the contents of a particular directory can be displayed by
    setting the tree view's root index:

    \snippet shareddirmodel/main.cpp 7

    The view's root index can be used to control how much of a
    hierarchical model is displayed. QFileSystemModel provides a convenience
    function that returns a suitable model index for a path to a
    directory within the model.

    \section1 Caching and Performance

    QFileSystemModel will not fetch any files or directories until setRootPath()
    is called.  This will prevent any unnecessary querying on the file system
    until that point such as listing the drives on Windows.

    Unlike QDirModel, QFileSystemModel uses a separate thread to populate
    itself so it will not cause the main thread to hang as the file system
    is being queried.  Calls to rowCount() will return 0 until the model
    populates a directory.

    QFileSystemModel keeps a cache with file information. The cache is
    automatically kept up to date using the QFileSystemWatcher.

    \sa {Model Classes}
*/

/*!
    \fn bool QFileSystemModel::rmdir(const QModelIndex &index)

    Removes the directory corresponding to the model item \a index in the
    file system model and \b{deletes the corresponding directory from the
    file system}, returning true if successful. If the directory cannot be
    removed, false is returned.

    \warning This function deletes directories from the file system; it does
    \b{not} move them to a location where they can be recovered.

    \sa remove()
*/

/*!
    \fn QIcon QFileSystemModel::fileName(const QModelIndex &index) const

    Returns the file name for the item stored in the model under the given
    \a index.
*/

/*!
    \fn QIcon QFileSystemModel::fileIcon(const QModelIndex &index) const

    Returns the icon for the item stored in the model under the given
    \a index.
*/

/*!
    \fn QFileInfo QFileSystemModel::fileInfo(const QModelIndex &index) const

    Returns the QFileInfo for the item stored in the model under the given
    \a index.
*/
QFileInfo QFileSystemModel::fileInfo(const QModelIndex &index) const
{
    Q_D(const QFileSystemModel);
    return d->node(index)->fileInfo();
}

/*!
    \fn void QFileSystemModel::rootPathChanged(const QString &newPath);

    This signal is emitted whenever the root path has been changed to a \a newPath.
*/

/*!
    \fn void QFileSystemModel::fileRenamed(const QString &path, const QString &oldName, const QString &newName)

    This signal is emitted whenever a file with the \a oldName is successfully
    renamed to \a newName.  The file is located in in the directory \a path.
*/

/*!
    \since 4.7
    \fn void QFileSystemModel::directoryLoaded(const QString &path)

    This signal is emitted when the gatherer thread has finished to load the \a path.

*/

/*!
    \fn bool QFileSystemModel::remove(const QModelIndex &index)

    Removes the model item \a index from the file system model and \b{deletes the
    corresponding file from the file system}, returning true if successful. If the
    item cannot be removed, false is returned.

    \warning This function deletes files from the file system; it does \b{not}
    move them to a location where they can be recovered.

    \sa rmdir()
*/

bool QFileSystemModel::remove(const QModelIndex &aindex)
{
    const QString path = filePath(aindex);
#ifndef QT_NO_FILESYSTEMWATCHER
    QFileSystemModelPrivate * d = const_cast<QFileSystemModelPrivate*>(d_func());
    d->fileInfoGatherer.removePath(path);
#endif
    if (QFileInfo(path).isFile())
        return QFile::remove(path);
    return QDir(path).removeRecursively();
}

/*!
  Constructs a file system model with the given \a parent.
*/
QFileSystemModel::QFileSystemModel(QObject *parent)
    : QAbstractItemModel(*new QFileSystemModelPrivate, parent)
{
    Q_D(QFileSystemModel);
    d->init();
}

/*!
    \internal
*/
QFileSystemModel::QFileSystemModel(QFileSystemModelPrivate &dd, QObject *parent)
    : QAbstractItemModel(dd, parent)
{
    Q_D(QFileSystemModel);
    d->init();
}

/*!
  Destroys this file system model.
*/
QFileSystemModel::~QFileSystemModel()
{
}

/*!
    \reimp
*/
QModelIndex QFileSystemModel::index(int row, int column, const QModelIndex &parent) const
{
    Q_D(const QFileSystemModel);
    if (row < 0 || column < 0 || row >= rowCount(parent) || column >= columnCount(parent))
        return QModelIndex();

    // get the parent node
    QFileSystemModelPrivate::QFileSystemNode *parentNode = (d->indexValid(parent) ? d->node(parent) :
                                                   const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&d->root));
    Q_ASSERT(parentNode);

    // now get the internal pointer for the index
    const QString &childName = parentNode->visibleChildren.at(d->translateVisibleLocation(parentNode, row));
    const QFileSystemModelPrivate::QFileSystemNode *indexNode = parentNode->children.value(childName);
    Q_ASSERT(indexNode);

    return createIndex(row, column, const_cast<QFileSystemModelPrivate::QFileSystemNode*>(indexNode));
}

/*!
    \overload

    Returns the model item index for the given \a path and \a column.
*/
QModelIndex QFileSystemModel::index(const QString &path, int column) const
{
    Q_D(const QFileSystemModel);
    QFileSystemModelPrivate::QFileSystemNode *node = d->node(path, false);
    return d->index(node, column);
}

/*!
    \internal

    Return the QFileSystemNode that goes to index.
  */
QFileSystemModelPrivate::QFileSystemNode *QFileSystemModelPrivate::node(const QModelIndex &index) const
{
    if (!index.isValid())
        return const_cast<QFileSystemNode*>(&root);
    QFileSystemModelPrivate::QFileSystemNode *indexNode = static_cast<QFileSystemModelPrivate::QFileSystemNode*>(index.internalPointer());
    Q_ASSERT(indexNode);
    return indexNode;
}

#ifdef Q_OS_WIN32
static QString qt_GetLongPathName(const QString &strShortPath)
{
    if (strShortPath.isEmpty()
        || strShortPath == QLatin1String(".") || strShortPath == QLatin1String(".."))
        return strShortPath;
    if (strShortPath.length() == 2 && strShortPath.endsWith(QLatin1Char(':')))
        return strShortPath.toUpper();
    const QString absPath = QDir(strShortPath).absolutePath();
    if (absPath.startsWith(QLatin1String("//"))
        || absPath.startsWith(QLatin1String("\\\\"))) // unc
        return QDir::fromNativeSeparators(absPath);
    if (absPath.startsWith(QLatin1Char('/')))
        return QString();
    const QString inputString = QLatin1String("\\\\?\\") + QDir::toNativeSeparators(absPath);
    QVarLengthArray<TCHAR, MAX_PATH> buffer(MAX_PATH);
    DWORD result = ::GetLongPathName((wchar_t*)inputString.utf16(),
                                     buffer.data(),
                                     buffer.size());
    if (result > DWORD(buffer.size())) {
        buffer.resize(result);
        result = ::GetLongPathName((wchar_t*)inputString.utf16(),
                                   buffer.data(),
                                   buffer.size());
    }
    if (result > 4) {
        QString longPath = QString::fromWCharArray(buffer.data() + 4); // ignoring prefix
        longPath[0] = longPath.at(0).toUpper(); // capital drive letters
        return QDir::fromNativeSeparators(longPath);
    } else {
        return QDir::fromNativeSeparators(strShortPath);
    }
}
#endif

/*!
    \internal

    Given a path return the matching QFileSystemNode or &root if invalid
*/
QFileSystemModelPrivate::QFileSystemNode *QFileSystemModelPrivate::node(const QString &path, bool fetch) const
{
    Q_Q(const QFileSystemModel);
    Q_UNUSED(q);
    if (path.isEmpty() || path == myComputer() || path.startsWith(QLatin1Char(':')))
        return const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&root);

    // Construct the nodes up to the new root path if they need to be built
    QString absolutePath;
#ifdef Q_OS_WIN32
    QString longPath = qt_GetLongPathName(path);
#else
    QString longPath = path;
#endif
    if (longPath == rootDir.path())
        absolutePath = rootDir.absolutePath();
    else
        absolutePath = QDir(longPath).absolutePath();

    // ### TODO can we use bool QAbstractFileEngine::caseSensitive() const?
    QStringList pathElements = absolutePath.split(QLatin1Char('/'), QString::SkipEmptyParts);
    if ((pathElements.isEmpty())
#if !defined(Q_OS_WIN) || defined(Q_OS_WINCE)
        && QDir::fromNativeSeparators(longPath) != QLatin1String("/")
#endif
        )
        return const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&root);
    QModelIndex index = QModelIndex(); // start with "My Computer"
#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
    if (absolutePath.startsWith(QLatin1String("//"))) { // UNC path
        QString host = QLatin1String("\\\\") + pathElements.first();
        if (absolutePath == QDir::fromNativeSeparators(host))
            absolutePath.append(QLatin1Char('/'));
        if (longPath.endsWith(QLatin1Char('/')) && !absolutePath.endsWith(QLatin1Char('/')))
            absolutePath.append(QLatin1Char('/'));
        int r = 0;
        QFileSystemModelPrivate::QFileSystemNode *rootNode = const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&root);
        if (!root.children.contains(host.toLower())) {
            if (pathElements.count() == 1 && !absolutePath.endsWith(QLatin1Char('/')))
                return rootNode;
            QFileInfo info(host);
            if (!info.exists())
                return rootNode;
            QFileSystemModelPrivate *p = const_cast<QFileSystemModelPrivate*>(this);
            p->addNode(rootNode, host,info);
            p->addVisibleFiles(rootNode, QStringList(host));
        }
        r = rootNode->visibleLocation(host);
        r = translateVisibleLocation(rootNode, r);
        index = q->index(r, 0, QModelIndex());
        pathElements.pop_front();
    } else
#endif

#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
    {
        if (!pathElements.at(0).contains(QLatin1Char(':'))) {
            QString rootPath = QDir(longPath).rootPath();
            pathElements.prepend(rootPath);
        }
        if (pathElements.at(0).endsWith(QLatin1Char('/')))
            pathElements[0].chop(1);
    }
#else
    // add the "/" item, since it is a valid path element on Unix
    if (absolutePath[0] == QLatin1Char('/'))
        pathElements.prepend(QLatin1String("/"));
#endif

    QFileSystemModelPrivate::QFileSystemNode *parent = node(index);

    for (int i = 0; i < pathElements.count(); ++i) {
        QString element = pathElements.at(i);
#ifdef Q_OS_WIN
        // On Windows, "filename    " and "filename" are equivalent and
        // "filename  .  " and "filename" are equivalent
        // "filename......." and "filename" are equivalent Task #133928
        // whereas "filename  .txt" is still "filename  .txt"
        // If after stripping the characters there is nothing left then we
        // just return the parent directory as it is assumed that the path
        // is referring to the parent
        while (element.endsWith(QLatin1Char('.')) || element.endsWith(QLatin1Char(' ')))
            element.chop(1);
        // Only filenames that can't possibly exist will be end up being empty
        if (element.isEmpty())
            return parent;
#endif
        bool alreadyExisted = parent->children.contains(element);

        // we couldn't find the path element, we create a new node since we
        // _know_ that the path is valid
        if (alreadyExisted) {
            if ((parent->children.count() == 0)
                || (parent->caseSensitive()
                    && parent->children.value(element)->fileName != element)
                || (!parent->caseSensitive()
                    && parent->children.value(element)->fileName.toLower() != element.toLower()))
                alreadyExisted = false;
        }

        QFileSystemModelPrivate::QFileSystemNode *node;
        if (!alreadyExisted) {
            // Someone might call ::index("file://cookie/monster/doesn't/like/veggies"),
            // a path that doesn't exists, I.E. don't blindly create directories.
            QFileInfo info(absolutePath);
            if (!info.exists())
                return const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&root);
            QFileSystemModelPrivate *p = const_cast<QFileSystemModelPrivate*>(this);
            node = p->addNode(parent, element,info);
#ifndef QT_NO_FILESYSTEMWATCHER
            node->populate(fileInfoGatherer.getInfo(info));
#endif
        } else {
            node = parent->children.value(element);
        }

        Q_ASSERT(node);
        if (!node->isVisible) {
            // It has been filtered out
            if (alreadyExisted && node->hasInformation() && !fetch)
                return const_cast<QFileSystemModelPrivate::QFileSystemNode*>(&root);

            QFileSystemModelPrivate *p = const_cast<QFileSystemModelPrivate*>(this);
            p->addVisibleFiles(parent, QStringList(element));
            if (!p->bypassFilters.contains(node))
                p->bypassFilters[node] = 1;
            QString dir = q->filePath(this->index(parent));
            if (!node->hasInformation() && fetch) {
                Fetching f;
                f.dir = dir;
                f.file = element;
                f.node = node;
                p->toFetch.append(f);
                p->fetchingTimer.start(0, const_cast<QFileSystemModel*>(q));
            }
        }
        parent = node;
    }

    return parent;
}

/*!
    \reimp
*/
void QFileSystemModel::timerEvent(QTimerEvent *event)
{
    Q_D(QFileSystemModel);
    if (event->timerId() == d->fetchingTimer.timerId()) {
        d->fetchingTimer.stop();
#ifndef QT_NO_FILESYSTEMWATCHER
        for (int i = 0; i < d->toFetch.count(); ++i) {
            const QFileSystemModelPrivate::QFileSystemNode *node = d->toFetch.at(i).node;
            if (!node->hasInformation()) {
                d->fileInfoGatherer.fetchExtendedInformation(d->toFetch.at(i).dir,
                                                 QStringList(d->toFetch.at(i).file));
            } else {
                // qDebug("yah!, you saved a little gerbil soul");
            }
        }
#endif
        d->toFetch.clear();
    }
}

/*!
    Returns \c true if the model item \a index represents a directory;
    otherwise returns \c false.
*/
bool QFileSystemModel::isDir(const QModelIndex &index) const
{
    // This function is for public usage only because it could create a file info
    Q_D(const QFileSystemModel);
    if (!index.isValid())
        return true;
    QFileSystemModelPrivate::QFileSystemNode *n = d->node(index);
    if (n->hasInformation())
        return n->isDir();
    return fileInfo(index).isDir();
}

/*!
    Returns the size in bytes of \a index. If the file does not exist, 0 is returned.
  */
qint64 QFileSystemModel::size(const QModelIndex &index) const
{
    Q_D(const QFileSystemModel);
    if (!index.isValid())
        return 0;
    return d->node(index)->size();
}

/*!
    Returns the type of file \a index such as "Directory" or "JPEG file".
  */
QString QFileSystemModel::type(const QModelIndex &index) const
{
    Q_D(const QFileSystemModel);
    if (!index.isValid())
        return QString();
    return d->node(index)->type();
}

/*!
    Returns the date and time when \a index was last modified.
 */
QDateTime QFileSystemModel::lastModified(const QModelIndex &index) const
{
    Q_D(const QFileSystemModel);
    if (!index.isValid())
        return QDateTime();
    return d->node(index)->lastModified();
}

/*!
    \reimp
*/
QModelIndex QFileSystemModel::parent(const QModelIndex &index) const
{
    Q_D(const QFileSystemModel);
    if (!d->indexValid(index))
        return QModelIndex();

    QFileSystemModelPrivate::QFileSystemNode *indexNode = d->node(index);
    Q_ASSERT(indexNode != 0);
    QFileSystemModelPrivate::QFileSystemNode *parentNode = indexNode->parent;
    if (parentNode == 0 || parentNode == &d->root)
        return QModelIndex();

    // get the parent's row
    QFileSystemModelPrivate::QFileSystemNode *grandParentNode = parentNode->parent;
    Q_ASSERT(grandParentNode->children.contains(parentNode->fileName));
    int visualRow = d->translateVisibleLocation(grandParentNode, grandParentNode->visibleLocation(grandParentNode->children.value(parentNode->fileName)->fileName));
    if (visualRow == -1)
        return QModelIndex();
    return createIndex(visualRow, 0, parentNode);
}

/*
    \internal

    return the index for node
*/
QModelIndex QFileSystemModelPrivate::index(const QFileSystemModelPrivate::QFileSystemNode *node, int column) const
{
    Q_Q(const QFileSystemModel);
    QFileSystemModelPrivate::QFileSystemNode *parentNode = (node ? node->parent : 0);
    if (node == &root || !parentNode)
        return QModelIndex();

    // get the parent's row
    Q_ASSERT(node);
    if (!node->isVisible)
        return QModelIndex();

    int visualRow = translateVisibleLocation(parentNode, parentNode->visibleLocation(node->fileName));
    return q->createIndex(visualRow, column, const_cast<QFileSystemNode*>(node));
}

/*!
    \reimp
*/
bool QFileSystemModel::hasChildren(const QModelIndex &parent) const
{
    Q_D(const QFileSystemModel);
    if (parent.column() > 0)
        return false;

    if (!parent.isValid()) // drives
        return true;

    const QFileSystemModelPrivate::QFileSystemNode *indexNode = d->node(parent);
    Q_ASSERT(indexNode);
    return (indexNode->isDir());
}

/*!
    \reimp
 */
bool QFileSystemModel::canFetchMore(const QModelIndex &parent) const
{
    Q_D(const QFileSystemModel);
    const QFileSystemModelPrivate::QFileSystemNode *indexNode = d->node(parent);
    return (!indexNode->populatedChildren);
}

/*!
    \reimp
 */
void QFileSystemModel::fetchMore(const QModelIndex &parent)
{
    Q_D(QFileSystemModel);
    if (!d->setRootPath)
        return;
    QFileSystemModelPrivate::QFileSystemNode *indexNode = d->node(parent);
    if (indexNode->populatedChildren)
        return;
    indexNode->populatedChildren = true;
#ifndef QT_NO_FILESYSTEMWATCHER
    d->fileInfoGatherer.list(filePath(parent));
#endif
}

/*!
    \reimp
*/
int QFileSystemModel::rowCount(const QModelIndex &parent) const
{
    Q_D(const QFileSystemModel);
    if (parent.column() > 0)
        return 0;

    if (!parent.isValid())
        return d->root.visibleChildren.count();

    const QFileSystemModelPrivate::QFileSystemNode *parentNode = d->node(parent);
    return parentNode->visibleChildren.count();
}

/*!
    \reimp
*/
int QFileSystemModel::columnCount(const QModelIndex &parent) const
{
    return (parent.column() > 0) ? 0 : QFileSystemModelPrivate::NumColumns;
}

/*!
    Returns the data stored under the given \a role for the item "My Computer".

    \sa Qt::ItemDataRole
 */
QVariant QFileSystemModel::myComputer(int role) const
{
#ifndef QT_NO_FILESYSTEMWATCHER
    Q_D(const QFileSystemModel);
#endif
    switch (role) {
    case Qt::DisplayRole:
        return QFileSystemModelPrivate::myComputer();
#ifndef QT_NO_FILESYSTEMWATCHER
    case Qt::DecorationRole:
        return d->fileInfoGatherer.iconProvider()->icon(QFileIconProvider::Computer);
#endif
    }
    return QVariant();
}

/*!
    \reimp
*/
QVariant QFileSystemModel::data(const QModelIndex &index, int role) const
{
    Q_D(const QFileSystemModel);
    if (!index.isValid() || index.model() != this)
        return QVariant();

    switch (role) {
    case Qt::EditRole:
    case Qt::DisplayRole:
        switch (index.column()) {
        case 0: return d->displayName(index);
        case 1: return d->size(index);
        case 2: return d->type(index);
        case 3: return d->time(index);
        default:
            qWarning("data: invalid display value column %d", index.column());
            break;
        }
        break;
    case FilePathRole:
        return filePath(index);
    case FileNameRole:
        return d->name(index);
    case Qt::DecorationRole:
        if (index.column() == 0) {
            QIcon icon = d->icon(index);
#ifndef QT_NO_FILESYSTEMWATCHER
            if (icon.isNull()) {
                if (d->node(index)->isDir())
                    icon = d->fileInfoGatherer.iconProvider()->icon(QFileIconProvider::Folder);
                else
                    icon = d->fileInfoGatherer.iconProvider()->icon(QFileIconProvider::File);
            }
#endif // QT_NO_FILESYSTEMWATCHER
            return icon;
        }
        break;
    case Qt::TextAlignmentRole:
        if (index.column() == 1)
            return Qt::AlignRight;
        break;
    case FilePermissions:
        int p = permissions(index);
        return p;
    }

    return QVariant();
}

/*!
    \internal
*/
QString QFileSystemModelPrivate::size(const QModelIndex &index) const
{
    if (!index.isValid())
        return QString();
    const QFileSystemNode *n = node(index);
    if (n->isDir()) {
#ifdef Q_OS_MAC
        return QLatin1String("--");
#else
        return QLatin1String("");
#endif
    // Windows   - ""
    // OS X      - "--"
    // Konqueror - "4 KB"
    // Nautilus  - "9 items" (the number of children)
    }
    return size(n->size());
}

QString QFileSystemModelPrivate::size(qint64 bytes)
{
    // According to the Si standard KB is 1000 bytes, KiB is 1024
    // but on windows sizes are calculated by dividing by 1024 so we do what they do.
    const qint64 kb = 1024;
    const qint64 mb = 1024 * kb;
    const qint64 gb = 1024 * mb;
    const qint64 tb = 1024 * gb;
    if (bytes >= tb)
        return QFileSystemModel::tr("%1 TB").arg(QLocale().toString(qreal(bytes) / tb, 'f', 3));
    if (bytes >= gb)
        return QFileSystemModel::tr("%1 GB").arg(QLocale().toString(qreal(bytes) / gb, 'f', 2));
    if (bytes >= mb)
        return QFileSystemModel::tr("%1 MB").arg(QLocale().toString(qreal(bytes) / mb, 'f', 1));
    if (bytes >= kb)
        return QFileSystemModel::tr("%1 KB").arg(QLocale().toString(bytes / kb));
    return QFileSystemModel::tr("%1 bytes").arg(QLocale().toString(bytes));
}

/*!
    \internal
*/
QString QFileSystemModelPrivate::time(const QModelIndex &index) const
{
    if (!index.isValid())
        return QString();
#ifndef QT_NO_DATESTRING
    return node(index)->lastModified().toString(Qt::SystemLocaleDate);
#else
    Q_UNUSED(index);
    return QString();
#endif
}

/*
    \internal
*/
QString QFileSystemModelPrivate::type(const QModelIndex &index) const
{
    if (!index.isValid())
        return QString();
    return node(index)->type();
}

/*!
    \internal
*/
QString QFileSystemModelPrivate::name(const QModelIndex &index) const
{
    if (!index.isValid())
        return QString();
    QFileSystemNode *dirNode = node(index);
    if (
#ifndef QT_NO_FILESYSTEMWATCHER
        fileInfoGatherer.resolveSymlinks() &&
#endif
        !resolvedSymLinks.isEmpty() && dirNode->isSymLink(/* ignoreNtfsSymLinks = */ true)) {
        QString fullPath = QDir::fromNativeSeparators(filePath(index));
        return resolvedSymLinks.value(fullPath, dirNode->fileName);
    }
    return dirNode->fileName;
}

/*!
    \internal
*/
QString QFileSystemModelPrivate::displayName(const QModelIndex &index) const
{
#if defined(Q_OS_WIN) && !defined(Q_OS_WINCE)
    QFileSystemNode *dirNode = node(index);
    if (!dirNode->volumeName.isNull())
        return dirNode->volumeName + QLatin1String(" (") + name(index) + QLatin1Char(')');
#endif
    return name(index);
}

/*!
    \internal
*/
QIcon QFileSystemModelPrivate::icon(const QModelIndex &index) const
{
    if (!index.isValid())
        return QIcon();
    return node(index)->icon();
}

/*!
    \reimp
*/
bool QFileSystemModel::setData(const QModelIndex &idx, const QVariant &value, int role)
{
    Q_D(QFileSystemModel);
    if (!idx.isValid()
        || idx.column() != 0
        || role != Qt::EditRole
        || (flags(idx) & Qt::ItemIsEditable) == 0) {
        return false;
    }

    QString newName = value.toString();
    QString oldName = idx.data().toString();
    if (newName == idx.data().toString())
        return true;

    if (newName.isEmpty()
        || QDir::toNativeSeparators(newName).contains(QDir::separator())
        || !QDir(filePath(parent(idx))).rename(oldName, newName)) {
#ifndef QT_NO_MESSAGEBOX
        QMessageBox::information(0, QFileSystemModel::tr("Invalid filename"),
                                QFileSystemModel::tr("<b>The name \"%1\" can not be used.</b><p>Try using another name, with fewer characters or no punctuations marks.")
                                .arg(newName),
                                 QMessageBox::Ok);
#endif // QT_NO_MESSAGEBOX
        return false;
    } else {
        /*
            *After re-naming something we don't want the selection to change*
            - can't remove rows and later insert
            - can't quickly remove and insert
            - index pointer can't change because treeview doesn't use persistant index's

            - if this get any more complicated think of changing it to just
              use layoutChanged
         */

        QFileSystemModelPrivate::QFileSystemNode *indexNode = d->node(idx);
        QFileSystemModelPrivate::QFileSystemNode *parentNode = indexNode->parent;
        int visibleLocation = parentNode->visibleLocation(parentNode->children.value(indexNode->fileName)->fileName);

        d->addNode(parentNode, newName,indexNode->info->fileInfo());
        parentNode->visibleChildren.removeAt(visibleLocation);
        QFileSystemModelPrivate::QFileSystemNode * oldValue = parentNode->children.value(oldName);
        parentNode->children[newName] = oldValue;
        QFileInfo info(d->rootDir, newName);
        oldValue->fileName = newName;
        oldValue->parent = parentNode;
#ifndef QT_NO_FILESYSTEMWATCHER
        oldValue->populate(d->fileInfoGatherer.getInfo(info));
#endif
        oldValue->isVisible = true;

        parentNode->children.remove(oldName);
        parentNode->visibleChildren.insert(visibleLocation, newName);

        d->delayedSort();
        emit fileRenamed(filePath(idx.parent()), oldName, newName);
    }
    return true;
}

/*!
    \reimp
*/
QVariant QFileSystemModel::headerData(int section, Qt::Orientation orientation, int role) const
{
    switch (role) {
    case Qt::DecorationRole:
        if (section == 0) {
            // ### TODO oh man this is ugly and doesn't even work all the way!
            // it is still 2 pixels off
            QImage pixmap(16, 1, QImage::Format_Mono);
            pixmap.fill(0);
            pixmap.setAlphaChannel(pixmap.createAlphaMask());
            return pixmap;
        }
        break;
    case Qt::TextAlignmentRole:
        return Qt::AlignLeft;
    }

    if (orientation != Qt::Horizontal || role != Qt::DisplayRole)
        return QAbstractItemModel::headerData(section, orientation, role);

    QString returnValue;
    switch (section) {
    case 0: returnValue = tr("Name");
            break;
    case 1: returnValue = tr("Size");
            break;
    case 2: returnValue =
#ifdef Q_OS_MAC
                   tr("Kind", "Match OS X Finder");
#else
                   tr("Type", "All other platforms");
#endif
           break;
    // Windows   - Type
    // OS X      - Kind
    // Konqueror - File Type
    // Nautilus  - Type
    case 3: returnValue = tr("Date Modified");
            break;
    default: return QVariant();
    }
    return returnValue;
}

/*!
    \reimp
*/
Qt::ItemFlags QFileSystemModel::flags(const QModelIndex &index) const
{
    Q_D(const QFileSystemModel);
    Qt::ItemFlags flags = QAbstractItemModel::flags(index);
    if (!index.isValid())
        return flags;

    QFileSystemModelPrivate::QFileSystemNode *indexNode = d->node(index);
    if (d->nameFilterDisables && !d->passNameFilters(indexNode)) {
        flags &= ~Qt::ItemIsEnabled;
        // ### TODO you shouldn't be able to set this as the current item, task 119433
        return flags;
    }

    flags |= Qt::ItemIsDragEnabled;
    if (d->readOnly)
        return flags;
    if ((index.column() == 0) && indexNode->permissions() & QFile::WriteUser) {
        flags |= Qt::ItemIsEditable;
        if (indexNode->isDir())
            flags |= Qt::ItemIsDropEnabled;
        else
            flags |= Qt::ItemNeverHasChildren;
    }
    return flags;
}

/*!
    \internal
*/
void QFileSystemModelPrivate::_q_performDelayedSort()
{
    Q_Q(QFileSystemModel);
    q->sort(sortColumn, sortOrder);
}

static inline QChar getNextChar(const QString &s, int location)
{
    return (location < s.length()) ? s.at(location) : QChar();
}

/*!
    Natural number sort, skips spaces.

    Examples:
    1, 2, 10, 55, 100
    01.jpg, 2.jpg, 10.jpg

    Note on the algorithm:
    Only as many characters as necessary are looked at and at most they all
    are looked at once.

    Slower then QString::compare() (of course)
  */
int QFileSystemModelPrivate::naturalCompare(const QString &s1, const QString &s2,  Qt::CaseSensitivity cs)