qdir.cpp

QT 开发环境里面一个很重要的文件

    If the directory of the current user's profile does not exist or
    cannot be retrieved, the following alternatives will be checked (in
    the given order) until an existing and available path is found:

    \list 1
    \o The path specified by the \c USERPROFILE environment variable.
    \o The path formed by concatenating the \c HOMEDRIVE and \c HOMEPATH
    environment variables.
    \o The path specified by the \c HOME environment variable.
    \o The path returned by the rootPath() function (which uses the \c SystemDrive
    environment variable)
    \o  The \c{C:\} directory.
    \endlist

    Under non-Windows operating systems the \c HOME environment
    variable is used if it exists, otherwise the path returned by the
    rootPath() function is used.

    \sa home(), currentPath(), rootPath(), tempPath()
*/

QString QDir::homePath()
{
    return QFSFileEngine::homePath();
}

/*!
    \fn QDir QDir::temp()

    Returns the system's temporary directory.

    The directory is constructed using the absolute path of the temporary directory,
    ensuring that its path() will be the same as its absolutePath().

    See tempPath() for details.

    \sa drives(), current(), home(), root()
*/

/*!
    Returns the absolute path of the system's temporary directory.

    On Unix/Linux systems this is usually \c{/tmp}; on Windows this is
    usually the path in the \c TEMP or \c TMP environment
    variable. Whether a directory separator is added to the end or
    not, depends on the operating system.

    \sa temp(), currentPath(), homePath(), rootPath()
*/
QString QDir::tempPath()
{
    return QFSFileEngine::tempPath();
}

/*!
    \fn QDir QDir::root()

    Returns the root directory.

    The directory is constructed using the absolute path of the root directory,
    ensuring that its path() will be the same as its absolutePath().

    See rootPath() for details.

    \sa drives(), current(), home(), temp()
*/

/*!
    Returns the absolute path of the root directory.

    For Unix operating systems this returns "/". For Windows file
    systems this normally returns "c:/".

    \sa root(), drives(), currentPath(), homePath(), tempPath()
*/

QString QDir::rootPath()
{
    return QFSFileEngine::rootPath();
}

#ifndef QT_NO_REGEXP
/*!
    \overload

    Returns true if the \a fileName matches any of the wildcard (glob)
    patterns in the list of \a filters; otherwise returns false. The
    matching is case insensitive.

    \sa {QRegExp wildcard matching}, QRegExp::exactMatch() entryList() entryInfoList()
*/


bool QDir::match(const QStringList &filters, const QString &fileName)
{
    for(QStringList::ConstIterator sit = filters.begin(); sit != filters.end(); ++sit) {
        QRegExp rx(*sit, Qt::CaseInsensitive, QRegExp::Wildcard);
        if (rx.exactMatch(fileName))
            return true;
    }
    return false;
}

/*!
    Returns true if the \a fileName matches the wildcard (glob)
    pattern \a filter; otherwise returns false. The \a filter may
    contain multiple patterns separated by spaces or semicolons.
    The matching is case insensitive.

    \sa {QRegExp wildcard matching}, QRegExp::exactMatch() entryList() entryInfoList()
*/

bool QDir::match(const QString &filter, const QString &fileName)
{
    return match(nameFiltersFromString(filter), fileName);
}
#endif

/*!
    Removes all multiple directory separators "/" and resolves any
    "."s or ".."s found in the path, \a path.

    Symbolic links are kept. This function does not return the
    canonical path, but rather the simplest version of the input.
    For example, "./local" becomes "local", "local/../bin" becomes
    "bin" and "/local/usr/../bin" becomes "/local/bin".

    \sa absolutePath() canonicalPath()
*/

QString QDir::cleanPath(const QString &path)
{
    if (path.isEmpty())
        return path;
    QString name = path;
    QChar dir_separator = separator();
    if(dir_separator != QLatin1Char('/'))
	name.replace(dir_separator, QLatin1Char('/'));

    int used = 0, levels = 0;
    const int len = name.length();
    QVector<QChar> out(len);
    const QChar *p = name.unicode();
    for(int i = 0, last = -1, iwrite = 0; i < len; i++) {
        if(p[i] == QLatin1Char('/')) {
            while(i < len-1 && p[i+1] == QLatin1Char('/')) {
#ifdef Q_OS_WIN //allow unc paths
                if(!i)
                    break;
#endif
                i++;
            }
            bool eaten = false;
            if(i < len - 1 && p[i+1] == QLatin1Char('.')) {
                int dotcount = 1;
                if(i < len - 2 && p[i+2] == QLatin1Char('.'))
                    dotcount++;
                if(i == len - dotcount - 1) {
                    if(dotcount == 1) {
                        break;
                    } else if(levels) {
                        if(last == -1) {
                            for(int i2 = iwrite-1; i2 >= 0; i2--) {
                                if(out[i2] == QLatin1Char('/')) {
                                    last = i2;
                                    break;
                                }
                            }
                        }
                        used -= iwrite - last - 1;
                        break;
                    }
                } else if(p[i+dotcount+1] == QLatin1Char('/')) {
                    if(dotcount == 2 && levels) {
                        if(last == -1 || iwrite - last == 1) {
                            for(int i2 = (last == -1) ? (iwrite-1) : (last-1); i2 >= 0; i2--) {
                                if(out[i2] == QLatin1Char('/')) {
                                    eaten = true;
                                    last = i2;
                                    break;
                                }
                            }
                        } else {
                            eaten = true;
                        }
                        if(eaten) {
                            levels--;
                            used -= iwrite - last;
                            iwrite = last;
                            last = -1;
                        }
                    } else if(dotcount == 1) {
                        eaten = true;
                    }
                    if(eaten)
                        i += dotcount;
                } else {
                    levels++;
                }
            } else if(last != -1 && iwrite - last == 1) {
#ifdef Q_OS_WIN
                eaten = (iwrite > 2);
#else
                eaten = true;
#endif
                last = -1;
            } else if(last != -1 && i == len-1) {
                eaten = true;
            } else {
                levels++;
            }
            if(!eaten)
                last = i - (i - iwrite);
            else
                continue;
        } else if(!i && p[i] == QLatin1Char('.')) {
            int dotcount = 1;
            if(len >= 1 && p[1] == QLatin1Char('.'))
                dotcount++;
            if(len >= dotcount && p[dotcount] == QLatin1Char('/')) {
                if(dotcount == 1) {
                    i++;
                    while(i+1 < len-1 && p[i+1] == QLatin1Char('/'))
                        i++;
                    continue;
                }
            }
        }
        out[iwrite++] = p[i];
        used++;
    }
    QString ret;
    if(used == len)
        ret = name;
    else
	ret = QString(out.data(), used);

    // Strip away last slash except for root directories
    if (ret.endsWith(QLatin1Char('/'))
        && !(ret.size() == 1 || (ret.size() == 3 && ret.at(1) == QLatin1Char(':'))))
        ret = ret.left(ret.length() - 1);

    return ret;
}

/*!
    Returns true if \a path is relative; returns false if it is
    absolute.

    \sa isRelative() isAbsolutePath() makeAbsolute()
*/

bool QDir::isRelativePath(const QString &path)
{
    return QFileInfo(path).isRelative();
}

/*!
    Refreshes the directory information.
*/

void QDir::refresh() const
{
    Q_D(const QDir);

    d->data->clear();
}

/*!
    \internal

    Returns a list of name filters from the given \a nameFilter. (If
    there is more than one filter, each pair of filters is separated
    by a space or by a semicolon.)
*/

QStringList QDir::nameFiltersFromString(const QString &nameFilter)
{
    return QDirPrivate::splitFilters(nameFilter);
}

/*!
    \macro void Q_INIT_RESOURCE(name)
    \relates QDir

    Initializes the resources specified by the \c .qrc file with the
    specified base \a name. Normally, Qt resources are loaded
    automatically at startup. The Q_INIT_RESOURCE() macro is
    necessary on some platforms for resources stored in a static
    library.

    For example, if your application's resources are listed in a file
    called \c myapp.qrc, you can ensure that the resources are
    initialized at startup by adding this line to your \c main()
    function:

    \code
        Q_INIT_RESOURCE(myapp);
    \endcode

    Note: This macro cannot be used in a namespace. It should be called from
    main(). If that is not possible, the following workaround can be used
    to init the resource \c myapp from the function \c{MyNamespace::myFunction}:

    \code
    inline void initMyResource() { Q_INIT_RESOURCE(myapp); }

    namespace MyNamespace
    {
        ...

        void myFunction()
        {
            initMyResource();
        }
    }
    \endcode

    \sa Q_CLEANUP_RESOURCE(), {The Qt Resource System}
*/

/*!
    \since 4.1
    \macro void Q_CLEANUP_RESOURCE(name)
    \relates QDir

    Unloads the resources specified by the \c .qrc file with the base
    name \a name.

    Normally, Qt resources are unloaded automatically when the
    application terminates, but if the resources are located in a
    plugin that is being unloaded, call Q_CLEANUP_RESOURCE() to force
    removal of your resources.

    Note: This macro cannot be used in a namespace. Please see the
    Q_INIT_RESOURCE documentation for a workaround.

    Example:

    \code
        Q_CLEANUP_RESOURCE(myapp);
    \endcode

    \sa Q_INIT_RESOURCE(), {The Qt Resource System}
*/

#ifdef QT3_SUPPORT

/*!
    \fn bool QDir::matchAllDirs() const

    Use filter() & AllDirs instead.
*/
bool QDir::matchAllDirs() const
{
    Q_D(const QDir);
    return d->matchAllDirs;
}


/*!
    \fn void QDir::setMatchAllDirs(bool on)

    Use setFilter() instead.
*/
void QDir::setMatchAllDirs(bool on)
{
    Q_D(QDir);
    d->matchAllDirs = on;
}

/*!
    Use nameFilters() instead.
*/
QString QDir::nameFilter() const
{
    Q_D(const QDir);

    return nameFilters().join(QString(d->filterSepChar));
}

/*!
    Use setNameFilters() instead.

    The \a nameFilter is a wildcard (globbing) filter that understands
    "*" and "?" wildcards. (See \l{QRegExp wildcard matching}.) You may
    specify several filter entries, each separated by spaces or by
    semicolons.

    For example, if you want entryList() and entryInfoList() to list
    all files ending with either ".cpp" or ".h", you would use either
    dir.setNameFilters("*.cpp *.h") or dir.setNameFilters("*.cpp;*.h").

    \oldcode
        QString filter = "*.cpp *.cxx *.cc";
        dir.setNameFilter(filter);
    \newcode
        QString filter = "*.cpp *.cxx *.cc";
        dir.setNameFilters(filter.split(' '));
    \endcode
*/
void QDir::setNameFilter(const QString &nameFilter)
{
    Q_D(QDir);

    d->filterSepChar = QDirPrivate::getFilterSepChar(nameFilter);
    setNameFilters(QDirPrivate::splitFilters(nameFilter, d->filterSepChar));
}

/*!
    \fn QString QDir::absPath() const

    Use absolutePath() instead.
*/

/*!
    \fn QString QDir::absFilePath(const QString &fileName, bool acceptAbsPath) const

    Use absoluteFilePath(\a fileName) instead.

    The \a acceptAbsPath parameter is ignored.
*/

/*!
    \fn bool QDir::mkdir(const QString &dirName, bool acceptAbsPath) const

    Use mkdir(\a dirName) instead.

    The \a acceptAbsPath parameter is ignored.
*/

/*!
    \fn bool QDir::rmdir(const QString &dirName, bool acceptAbsPath) const

    Use rmdir(\a dirName) instead.

    The \a acceptAbsPath parameter is ignored.
*/

/*!
    \fn QStringList QDir::entryList(const QString &nameFilter, Filters filters,
                                    SortFlags sort) const
    \overload

    Use the overload that takes a name filter string list as first
    argument instead of a combination of attribute filter flags.
*/

/*!
    \fn QFileInfoList QDir::entryInfoList(const QString &nameFilter, Filters filters,
                                          SortFlags sort) const
    \overload

    U