qdiriterator.cpp

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#include "qdiriterator.h"
#include "qdir_p.h"

#include "qabstractfileengine.h"

#include <QtCore/qset.h>
#include <QtCore/qstack.h>
#include <QtCore/qvariant.h>

#include <QtCore/private/qfilesystemiterator_p.h>
#include <QtCore/private/qfilesystementry_p.h>
#include <QtCore/private/qfilesystemmetadata_p.h>
#include <QtCore/private/qfilesystemengine_p.h>
#include <QtCore/qfsfileengine.h>
#include <QtCore/private/qfileinfo_p.h>

QT_BEGIN_NAMESPACE

template <class Iterator>
class QDirIteratorPrivateIteratorStack : public QStack<Iterator *>
{
public:
    ~QDirIteratorPrivateIteratorStack()
    {
        qDeleteAll(*this);
    }
};

class QDirIteratorPrivate
{
public:
    QDirIteratorPrivate(const QFileSystemEntry &entry, const QStringList &nameFilters,
                        QDir::Filters filters, QDirIterator::IteratorFlags flags, bool resolveEngine = true);

    void advance();

    bool entryMatches(const QString & fileName, const QFileInfo &fileInfo);
    void pushDirectory(const QFileInfo &fileInfo);
    void checkAndPushDirectory(const QFileInfo &);
    bool matchesFilters(const QString &fileName, const QFileInfo &fi) const;

    QScopedPointer<QAbstractFileEngine> engine;

    QFileSystemEntry dirEntry;
    const QStringList nameFilters;
    const QDir::Filters filters;
    const QDirIterator::IteratorFlags iteratorFlags;

#ifndef QT_NO_REGEXP
    QVector<QRegExp> nameRegExps;
#endif

    QDirIteratorPrivateIteratorStack<QAbstractFileEngineIterator> fileEngineIterators;
#ifndef QT_NO_FILESYSTEMITERATOR
    QDirIteratorPrivateIteratorStack<QFileSystemIterator> nativeIterators;
#endif

    QFileInfo currentFileInfo;
    QFileInfo nextFileInfo;

    // Loop protection
    QSet<QString> visitedLinks;
};

QDirIteratorPrivate::QDirIteratorPrivate(const QFileSystemEntry &entry, const QStringList &nameFilters,
                                         QDir::Filters filters, QDirIterator::IteratorFlags flags, bool resolveEngine)
    : dirEntry(entry)
      , nameFilters(nameFilters.contains(QLatin1String("*")) ? QStringList() : nameFilters)
      , filters(QDir::NoFilter == filters ? QDir::AllEntries : filters)
      , iteratorFlags(flags)
{
#ifndef QT_NO_REGEXP
    nameRegExps.reserve(nameFilters.size());
    for (int i = 0; i < nameFilters.size(); ++i)
        nameRegExps.append(
            QRegExp(nameFilters.at(i),
                    (filters & QDir::CaseSensitive) ? Qt::CaseSensitive : Qt::CaseInsensitive,
                    QRegExp::Wildcard));
#endif
    QFileSystemMetaData metaData;
    if (resolveEngine)
        engine.reset(QFileSystemEngine::resolveEntryAndCreateLegacyEngine(dirEntry, metaData));
    QFileInfo fileInfo(new QFileInfoPrivate(dirEntry, metaData));

    // Populate fields for hasNext() and next()
    pushDirectory(fileInfo);
    advance();
}

void QDirIteratorPrivate::pushDirectory(const QFileInfo &fileInfo)
{
    QString path = fileInfo.filePath();

#ifdef Q_OS_WIN
    if (fileInfo.isSymLink())
        path = fileInfo.canonicalFilePath();
#endif

    if (iteratorFlags & QDirIterator::FollowSymlinks)
        visitedLinks << fileInfo.canonicalFilePath();

    if (engine) {
        engine->setFileName(path);
        QAbstractFileEngineIterator *it = engine->beginEntryList(filters, nameFilters);
        if (it) {
            it->setPath(path);
            fileEngineIterators << it;
        } else {
            // No iterator; no entry list.
        }
    } else {
#ifndef QT_NO_FILESYSTEMITERATOR
        QFileSystemIterator *it = new QFileSystemIterator(fileInfo.d_ptr->fileEntry,
            filters, nameFilters, iteratorFlags);
        nativeIterators << it;
#endif
    }
}

inline bool QDirIteratorPrivate::entryMatches(const QString & fileName, const QFileInfo &fileInfo)
{
    checkAndPushDirectory(fileInfo);

    if (matchesFilters(fileName, fileInfo)) {
        currentFileInfo = nextFileInfo;
        nextFileInfo = fileInfo;

        //We found a matching entry.
        return true;
    }

    return false;
}

void QDirIteratorPrivate::advance()
{
    if (engine) {
        while (!fileEngineIterators.isEmpty()) {
            // Find the next valid iterator that matches the filters.
            QAbstractFileEngineIterator *it;
            while (it = fileEngineIterators.top(), it->hasNext()) {
                it->next();
                if (entryMatches(it->currentFileName(), it->currentFileInfo()))
                    return;
            }

            fileEngineIterators.pop();
            delete it;
        }
    } else {
#ifndef QT_NO_FILESYSTEMITERATOR
        QFileSystemEntry nextEntry;
        QFileSystemMetaData nextMetaData;

        while (!nativeIterators.isEmpty()) {
            // Find the next valid iterator that matches the filters.
            QFileSystemIterator *it;
            while (it = nativeIterators.top(), it->advance(nextEntry, nextMetaData)) {
                QFileInfo info(new QFileInfoPrivate(nextEntry, nextMetaData));

                if (entryMatches(nextEntry.fileName(), info))
                    return;
            }

            nativeIterators.pop();
            delete it;
        }
#endif
    }

    currentFileInfo = nextFileInfo;
    nextFileInfo = QFileInfo();
}

void QDirIteratorPrivate::checkAndPushDirectory(const QFileInfo &fileInfo)
{
    // If we're doing flat iteration, we're done.
    if (!(iteratorFlags & QDirIterator::Subdirectories))
        return;

    // Never follow non-directory entries
    if (!fileInfo.isDir())
        return;

    // Follow symlinks only when asked
    if (!(iteratorFlags & QDirIterator::FollowSymlinks) && fileInfo.isSymLink())
        return;

    // Never follow . and ..
    QString fileName = fileInfo.fileName();
    if (QLatin1String(".") == fileName || QLatin1String("..") == fileName)
        return;

    // No hidden directories unless requested
    if (!(filters & QDir::AllDirs) && !(filters & QDir::Hidden) && fileInfo.isHidden())
        return;

    // Stop link loops
    if (!visitedLinks.isEmpty() &&
        visitedLinks.contains(fileInfo.canonicalFilePath()))
        return;

    pushDirectory(fileInfo);
}

bool QDirIteratorPrivate::matchesFilters(const QString &fileName, const QFileInfo &fi) const
{
    Q_ASSERT(!fileName.isEmpty());

    // filter . and ..?
    const int fileNameSize = fileName.size();
    const bool dotOrDotDot = fileName[0] == QLatin1Char('.')
                             && ((fileNameSize == 1)
                                 ||(fileNameSize == 2 && fileName[1] == QLatin1Char('.')));
    if ((filters & QDir::NoDot) && dotOrDotDot && fileNameSize == 1)
        return false;
    if ((filters & QDir::NoDotDot) && dotOrDotDot && fileNameSize == 2)
        return false;
    if ((filters & QDir::NoDotAndDotDot) && dotOrDotDot) // ### Qt5 remove (NoDotAndDotDot == NoDot|NoDotDot)
        return false;

    // name filter
#ifndef QT_NO_REGEXP
    // Pass all entries through name filters, except dirs if the AllDirs
    if (!nameFilters.isEmpty() && !((filters & QDir::AllDirs) && fi.isDir())) {
        bool matched = false;
        for (QVector<QRegExp>::const_iterator iter = nameRegExps.constBegin(),
                                              end = nameRegExps.constEnd();
                iter != end; ++iter) {

            if (iter->exactMatch(fileName)) {
                matched = true;
                break;
            }
        }
        if (!matched)
            return false;
    }
#endif
    // skip symlinks
    const bool skipSymlinks = (filters & QDir::NoSymLinks);
    const bool includeSystem = (filters & QDir::System);
    if(skipSymlinks && fi.isSymLink()) {
        // The only reason to save this file is if it is a broken link and we are requesting system files.
        if(!includeSystem || fi.exists())
            return false;
    }

    // filter hidden
    const bool includeHidden = (filters & QDir::Hidden);
    if (!includeHidden && !dotOrDotDot && fi.isHidden())
        return false;

    // filter system files
    if (!includeSystem && (!(fi.isFile() || fi.isDir() || fi.isSymLink())
                    || (!fi.exists() && fi.isSymLink())))
        return false;

    // skip directories
    const bool skipDirs = !(filters & (QDir::Dirs | QDir::AllDirs));
    if (skipDirs && fi.isDir())
        return false;

    // skip files
    const bool skipFiles    = !(filters & QDir::Files);
    if (skipFiles && fi.isFile())
        // Basically we need a reason not to exclude this file otherwise we just eliminate it.
        return false;

    // filter permissions
    const bool filterPermissions = ((filters & QDir::PermissionMask)
                                    && (filters & QDir::PermissionMask) != QDir::PermissionMask);
    const bool doWritable = !filterPermissions || (filters & QDir::Writable);
    const bool doExecutable = !filterPermissions || (filters & QDir::Executable);
    const bool doReadable = !filterPermissions || (filters & QDir::Readable);
    if (filterPermissions
        && ((doReadable && !fi.isReadable())
            || (doWritable && !fi.isWritable())
            || (doExecutable && !fi.isExecutable()))) {
        return false;
    }

    return true;
}

QDirIterator::QDirIterator(const QDir &dir, IteratorFlags flags)
{
    // little trick to get hold of the QDirPrivate while there is no API on QDir to give it to us
    class MyQDir : public QDir { public: const QDirPrivate *priv() const { return d_ptr.constData(); } };
    const QDirPrivate *other = static_cast<const MyQDir*>(&dir)->priv();
    d.reset(new QDirIteratorPrivate(other->dirEntry, other->nameFilters, other->filters, flags, !other->fileEngine.isNull()));
}

QDirIterator::QDirIterator(const QString &path, QDir::Filters filters, IteratorFlags flags)
    : d(new QDirIteratorPrivate(QFileSystemEntry(path), QStringList(), filters, flags))
{
}

QDirIterator::QDirIterator(const QString &path, IteratorFlags flags)
    : d(new QDirIteratorPrivate(QFileSystemEntry(path), QStringList(), QDir::NoFilter, flags))
{
}

QDirIterator::QDirIterator(const QString &path, const QStringList &nameFilters,
                           QDir::Filters filters, IteratorFlags flags)
    : d(new QDirIteratorPrivate(QFileSystemEntry(path), nameFilters, filters, flags))
{
}

QDirIterator::~QDirIterator()
{
}

QString QDirIterator::next()
{
    d->advance();
    return filePath();
}

bool QDirIterator::hasNext() const
{
    if (d->engine)
        return !d->fileEngineIterators.isEmpty();
    else
#ifndef QT_NO_FILESYSTEMITERATOR
        return !d->nativeIterators.isEmpty();
#else
        return false;
#endif
}

QString QDirIterator::fileName() const
{
    return d->currentFileInfo.fileName();
}

QString QDirIterator::filePath() const
{
    return d->currentFileInfo.filePath();
}

QFileInfo QDirIterator::fileInfo() const
{
    return d->currentFileInfo;
}

QString QDirIterator::path() const
{
    return d->dirEntry.filePath();
}

QT_END_NAMESPACE