qdir.cpp

QT 开发环境里面一个很重要的文件

        return true;
    QString newPath = d->data->path;
    if (isAbsolutePath(dirName)) {
        newPath = cleanPath(dirName);
    } else {
        if (isRoot()) {
            if (dirName == QLatin1String(".."))
                return false;
        } else {
            newPath += QLatin1Char('/');
        }

        newPath += dirName;
        if (dirName.indexOf(QLatin1Char('/')) >= 0
            || d->data->path == QLatin1String(".")
            || dirName == QLatin1String("..")) {
            newPath = cleanPath(newPath);
            /*
              If newPath starts with .., we convert it to absolute to
              avoid infinite looping on

                  QDir dir(".");
                  while (dir.cdUp())
                      ;
            */
            if (newPath.startsWith(QLatin1String(".."))) {
                newPath = QFileInfo(newPath).absoluteFilePath();
            }
        }
    }
    {
        QFileInfo fi(newPath);
        if (!(fi.exists() && fi.isDir()))
            return false;
    }

    d->setPath(newPath);
    refresh();
    return true;
}

/*!
    Changes directory by moving one directory up from the QDir's
    current directory.

    Returns true if the new directory exists and is readable;
    otherwise returns false. Note that the logical cdUp() operation is
    not performed if the new directory does not exist.

    \sa cd(), isReadable(), exists(), path()
*/

bool QDir::cdUp()
{
    return cd(QString::fromLatin1(".."));
}

/*!
    Returns the string list set by setNameFilters()
*/

QStringList QDir::nameFilters() const
{
    Q_D(const QDir);

    return d->data->nameFilters;
}

/*!
    Sets the name filters used by entryList() and entryInfoList() to the
    list of filters specified by \a nameFilters.

    Each name filter is a wildcard (globbing) filter that understands
    \c{*} and \c{?} wildcards. (See \l{QRegExp wildcard matching}.)

    For example, the following code sets three name filters on a QDir
    to ensure that only files with extensions typically used for C++
    source files are listed:

    \quotefromfile snippets/qdir-namefilters/main.cpp
    \skipto QStringList
    \printuntil setNameFilters

    \sa nameFilters(), setFilter()
*/

void QDir::setNameFilters(const QStringList &nameFilters)
{
    Q_D(QDir);
    d->detach();
    d->data->nameFilters = nameFilters;
}

/*!
    Adds \a path to the search paths searched in to find resources
    that are not specified with an absolute path. The default search
    path is to search only in the root (\c{:/}).

    \sa {The Qt Resource System}, QResource::addSearchPath()
*/

void QDir::addResourceSearchPath(const QString &path)
{
#ifdef QT_BUILD_CORE_LIB
    QResource::addSearchPath(path);
#else
    Q_UNUSED(path)
#endif
}


/*!
    Returns the value set by setFilter()
*/

QDir::Filters QDir::filter() const
{
    Q_D(const QDir);

    return d->data->filters;
}

/*!
    \enum QDir::Filter

    This enum describes the filtering options available to QDir; e.g.
    for entryList() and entryInfoList(). The filter value is specified
    by combining values from the following list using the bitwise OR
    operator:

    \value Dirs    List directories that match the filters.
    \value AllDirs  List all directories; i.e. don't apply the filters
                    to directory names.
    \value Files   List files only.
    \value Drives  List disk drives (ignored under Unix).
    \value NoSymLinks  Do not list symbolic links (ignored by operating
                       systems that don't support symbolic links).
    \value NoDotAndDotDot Do not list the special entries "." and "..".
    \value AllEntries  List directories, files, drives and symlinks (this does not list
                broken symlinks unless you specify System).
    \value Readable    List files for which the application has read
                       access. The Readable value needs to be combined
                       with Dirs or Files.
    \value Writable    List files for which the application has write
                       access. The Writable value needs to be combined
                       with Dirs or Files.
    \value Executable  List files for which the application has
                       execute access. The Executable value needs to be
                       combined with Dirs or Files.
    \value Modified  Only list files that have been modified (ignored
                     under Unix).
    \value Hidden  List hidden files (on Unix, files starting with a .).
    \value System  List system files (on Unix, FIFOs, sockets and
                   device files)
    \value CaseSensitive  The filter should be case sensitive if the file system
                          is case sensitive.

    \omitvalue DefaultFilter
    \omitvalue TypeMask
    \omitvalue All
    \omitvalue RWEMask
    \omitvalue AccessMask
    \omitvalue PermissionMask
    \omitvalue NoFilter

    Functions that use Filter enum values to filter lists of files
    and directories will include symbolic links to files and directories
    unless you set the NoSymLinks value.

    A default constructed QDir will not filter out files based on
    their permissions, so entryList() and entryInfoList() will return
    all files that are readable, writable, executable, or any
    combination of the three.  This makes the default easy to write,
    and at the same time useful.

    For example, setting the \c Readable, \c Writable, and \c Files
    flags allows all files to be listed for which the application has read
    access, write access or both. If the \c Dirs and \c Drives flags are
    also included in this combination then all drives, directories, all
    files that the application can read, write, or execute, and symlinks
    to such files/directories can be listed.

    To retrieve the permissons for a directory, use the
    entryInfoList() function to get the associated QFileInfo objects
    and then use the QFileInfo::permissons() to obtain the permissions
    and ownership for each file.
*/

/*!
    Sets the filter used by entryList() and entryInfoList() to \a
    filters. The filter is used to specify the kind of files that
    should be returned by entryList() and entryInfoList(). See
    \l{QDir::Filter}.

    \sa filter(), setNameFilters()
*/

void QDir::setFilter(Filters filters)
{
    Q_D(QDir);

    d->detach();
    d->data->filters = filters;
}

/*!
    Returns the value set by setSorting()

    \sa setSorting() SortFlag
*/

QDir::SortFlags QDir::sorting() const
{
    Q_D(const QDir);

    return d->data->sort;
}

/*!
    \enum QDir::SortFlag

    This enum describes the sort options available to QDir, e.g. for
    entryList() and entryInfoList(). The sort value is specified by
    OR-ing together values from the following list:

    \value Name  Sort by name.
    \value Time  Sort by time (modification time).
    \value Size  Sort by file size.
    \value Type  Sort by file type (extension).
    \value Unsorted  Do not sort.

    \value DirsFirst  Put the directories first, then the files.
    \value DirsLast Put the files first, then the directories.
    \value Reversed  Reverse the sort order.
    \value IgnoreCase  Sort case-insensitively.
    \value LocaleAware Sort items appropriately using the current locale settings.

    \omitvalue SortByMask
    \omitvalue DefaultSort
    \omitvalue NoSort

    You can only specify one of the first four.

    If you specify both DirsFirst and Reversed, directories are
    still put first, but in reverse order; the files will be listed
    after the directories, again in reverse order.
*/

/*!
    Sets the sort order used by entryList() and entryInfoList().

    The \a sort is specified by OR-ing values from the enum
    \l{QDir::SortFlag}.

    \sa sorting() SortFlag
*/

void QDir::setSorting(SortFlags sort)
{
    Q_D(QDir);

    d->detach();
    d->data->sort = sort;
}


/*!
    Returns the total number of directories and files in the directory.

    Equivalent to entryList().count().

    \sa operator[](), entryList()
*/

uint QDir::count() const
{
    Q_D(const QDir);

    d->updateFileLists();
    return d->data->files.count();
}

/*!
    Returns the file name at position \a pos in the list of file
    names. Equivalent to entryList().at(index).

    Returns an empty string if \a pos is out of range or if the
    entryList() function failed.

    \sa count(), entryList()
*/

QString QDir::operator[](int pos) const
{
    Q_D(const QDir);

    d->updateFileLists();
    return d->data->files[pos];
}

/*!
    \overload

    Returns a list of the names of all the files and directories in
    the directory, ordered according to the name and attribute filters
    previously set with setNameFilters() and setFilter(), and sorted according
    to the flags set with setSorting().

    The attribute filter and sorting specifications can be overridden using the
    \a filters and \a sort arguments.

    Returns an empty list if the directory is unreadable, does not
    exist, or if nothing matches the specification.

    \sa entryInfoList(), setNameFilters(), setSorting(), setFilter()
*/

QStringList QDir::entryList(Filters filters, SortFlags sort) const
{
    Q_D(const QDir);

    return entryList(d->data->nameFilters, filters, sort);
}


/*!
    \overload

    Returns a list of QFileInfo objects for all the files and directories in
    the directory, ordered according to the name and attribute filters
    previously set with setNameFilters() and setFilter(), and sorted according
    to the flags set with setSorting().

    The attribute filter and sorting specifications can be overridden using the
    \a filters and \a sort arguments.

    Returns an empty list if the directory is unreadable, does not
    exist, or if nothing matches the specification.

    \sa entryList(), setNameFilters(), setSorting(), setFilter(), isReadable(), exists()
*/

QFileInfoList QDir::entryInfoList(Filters filters, SortFlags sort) const
{
    Q_D(const QDir);

    return entryInfoList(d->data->nameFilters, filters, sort);
}

/*!
    Returns a list of the names of all the files and
    directories in the directory, ordered according to the name
    and attribute filters previously set with setNameFilters()
    and setFilter(), and sorted according to the flags set with
    setSorting().

    The name filter, file attribute filter, and sorting specification
    can be overridden using the \a nameFilters, \a filters, and \a sort
    arguments.

    Returns an empty list if the directory is unreadable, does not
    exist, or if nothing matches the specification.

    \sa entryInfoList(), setNameFilters(), setSorting(), setFilter()
*/

QStringList QDir::entryList(const QStringList &nameFilters, Filters filters,
                            SortFlags sort) const
{
    Q_D(const QDir);

    if (filters == NoFilter)
        filters = d->data->filters;
#ifdef QT3_SUPPORT
    if (d->matchAllDirs)
        filters |= AllDirs;
#endif
    if (sort == NoSort)
        sort = d->data->sort;
    if (filters == NoFilter && sort == NoSort && nameFilters == d->data->nameFilters) {
        d->updateFileLists();
        return d->data->files;
    }
    QStringList l = d->data->fileEngine->entryList(filters, nameFilters);
    QStringList ret;
    d->sortFileList(sort, l, &ret, 0);
    return ret;
}

/*!
    Returns a list of QFileInfo objects for all the files and
    directories in the directory, ordered according to the name
    and attribute filters previously set with setNameFilters()
    and setFilter(), and sorted according to the flags set with
    setSorting().

    The name filter, file attribute filter, and sorting specification
    can be overridden using the \a nameFilters, \a filters, and \a sort
    arguments.

    Returns an empty list if the directory is unreadable, does not
    exist, or if nothing matches the specification.

    \sa entryList(), setNameFilters(), setSorting(), setFilter(), isReadable(), exists()
*/

QFileInfoList QDir::entryInfoList(const QStringList &nameFilters, Filters filters,
                                  SortFlags sort) const
{
    Q_D(const QDir);

    if (filters == NoFilter)
        filters = d->data->filters;
#ifdef QT3_SUPPORT
    if (d->matchAllDirs)
        filters |= AllDirs;
#endif
    if (sort == NoSort)
        sort = d->data->sort;
    if (filters == NoFilter && sort == NoSort && nameFilters == d->data->nameFilters) {
        d->updateFileLists();
        return d->data->fileInfos;
    }
    QFileInfoList ret;
    QStringList l = d->data->fileEngine->entryList(filters, nameFilters);
    d->sortFileList(sort, l, 0, &ret);
    return ret;
}

/*!
    Creates a sub-directory called \a dirName.

    Returns true on success; otherwise returns false.

    \sa rmdir()
*/

bool QDir::mkdir(const QString &dirName) const
{
    Q_D(const QDir);

    if (dirName.isEmpty()) {
        qWarning("QDir::mkdir: Empty or null file name(s)");
        return false;
    }
    if(!d->data->fileEngine)
        return false;

    QString fn = filePath(dirName);
    return d->data->fileEngine->mkdir(fn, false);
}

/*!
    Removes the directory specified by \a dirName.

    The directory must be empty for rmdir() to succeed.