qfilesystemwatcher_polling_p.h

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#ifndef QFILESYSTEMWATCHER_POLLING_P_H
#define QFILESYSTEMWATCHER_POLLING_P_H
 
//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API. It exists purely as an
// implementation detail. This header file may change from version to
// version without notice, or even be removed.
//
// We mean it.
//
 
#include <QtCore/qfileinfo.h>
#include <QtCore/qmutex.h>
#include <QtCore/qdatetime.h>
#include <QtCore/qdir.h>
#include <QtCore/qtimer.h>
#include <QtCore/qhash.h>
 
#include "qfilesystemwatcher_p.h"
 
QT_REQUIRE_CONFIG(filesystemwatcher);
QT_BEGIN_NAMESPACE
 
enum { PollingInterval = 1000 };
 
class QPollingFileSystemWatcherEngine : public QFileSystemWatcherEngine
{
    Q_OBJECT
 
    class FileInfo
    {
        uint ownerId;
        uint groupId;
        QFile::Permissions permissions;
        QDateTime lastModified;
        QStringList entries;
 
    public:
        FileInfo(const QFileInfo &fileInfo)
            : ownerId(fileInfo.ownerId()),
              groupId(fileInfo.groupId()),
              permissions(fileInfo.permissions()),
              lastModified(fileInfo.lastModified(QTimeZone::UTC))
        {
            if (fileInfo.isDir()) {
                entries = fileInfo.absoluteDir().entryList(QDir::AllEntries);
            }
        }
        FileInfo &operator=(const QFileInfo &fileInfo)
        {
            *this = FileInfo(fileInfo);
            return *this;
        }
 
        bool operator!=(const QFileInfo &fileInfo) const
        {
            if (fileInfo.isDir() && entries != fileInfo.absoluteDir().entryList(QDir::AllEntries))
                return true;
            return (ownerId != fileInfo.ownerId()
                    || groupId != fileInfo.groupId()
                    || permissions != fileInfo.permissions()
                    || lastModified != fileInfo.lastModified(QTimeZone::UTC));
        }
    };
 
    QHash<QString, FileInfo> files, directories;
 
public:
    QPollingFileSystemWatcherEngine(QObject *parent);
 
    QStringList addPaths(const QStringList &paths, QStringList *files, QStringList *directories) override;
    QStringList removePaths(const QStringList &paths, QStringList *files, QStringList *directories) override;
 
private Q_SLOTS:
    void timeout();
 
private:
    QTimer timer;
};
 
QT_END_NAMESPACE
#endif // QFILESYSTEMWATCHER_POLLING_P_H