qfiledevice.h

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// Copyright (C) 2020 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 QFILEDEVICE_H
#define QFILEDEVICE_H
 
#include <QtCore/qiodevice.h>
#include <QtCore/qstring.h>
 
QT_BEGIN_NAMESPACE
 
class QDateTime;
class QFileDevicePrivate;
 
#if !defined(QT_USE_NODISCARD_FILE_OPEN) && !defined(QT_NO_USE_NODISCARD_FILE_OPEN)
#  if QT_VERSION < QT_VERSION_CHECK(6, 10, 0)
#    define QT_NO_USE_NODISCARD_FILE_OPEN
#  else
#    define QT_USE_NODISCARD_FILE_OPEN
#  endif
#endif
 
#if defined(QT_USE_NODISCARD_FILE_OPEN) && defined(QT_NO_USE_NODISCARD_FILE_OPEN)
#error "Inconsistent macro definition for nodiscard QFile::open"
#elif defined(QT_USE_NODISCARD_FILE_OPEN)
#define QFILE_MAYBE_NODISCARD [[nodiscard]]
#else /* QT_NO_USE_NODISCARD_FILE_OPEN */
#define QFILE_MAYBE_NODISCARD
#endif
 
class Q_CORE_EXPORT QFileDevice : public QIODevice
{
#ifndef QT_NO_QOBJECT
    Q_OBJECT
#endif
    Q_DECLARE_PRIVATE(QFileDevice)
 
public:
    enum FileError {
        NoError = 0,
        ReadError = 1,
        WriteError = 2,
        FatalError = 3,
        ResourceError = 4,
        OpenError = 5,
        AbortError = 6,
        TimeOutError = 7,
        UnspecifiedError = 8,
        RemoveError = 9,
        RenameError = 10,
        PositionError = 11,
        ResizeError = 12,
        PermissionsError = 13,
        CopyError = 14
    };
 
    enum FileTime {
        FileAccessTime,
        FileBirthTime,
        FileMetadataChangeTime,
        FileModificationTime
    };
 
    enum Permission {
        ReadOwner = 0x4000, WriteOwner = 0x2000, ExeOwner = 0x1000,
        ReadUser  = 0x0400, WriteUser  = 0x0200, ExeUser  = 0x0100,
        ReadGroup = 0x0040, WriteGroup = 0x0020, ExeGroup = 0x0010,
        ReadOther = 0x0004, WriteOther = 0x0002, ExeOther = 0x0001
    };
    Q_DECLARE_FLAGS(Permissions, Permission)
 
    enum FileHandleFlag {
        AutoCloseHandle = 0x0001,
        DontCloseHandle = 0
    };
    Q_DECLARE_FLAGS(FileHandleFlags, FileHandleFlag)
 
    ~QFileDevice();
 
    FileError error() const;
    void unsetError();
 
    void close() override;
 
    bool isSequential() const override;
 
    int handle() const;
    virtual QString fileName() const;
 
    qint64 pos() const override;
    bool seek(qint64 offset) override;
    bool atEnd() const override;
    bool flush();
 
    qint64 size() const override;
 
    virtual bool resize(qint64 sz);
    virtual Permissions permissions() const;
    virtual bool setPermissions(Permissions permissionSpec);
 
    enum MemoryMapFlag {
        NoOptions = 0,
        MapPrivateOption = 0x0001
    };
    Q_DECLARE_FLAGS(MemoryMapFlags, MemoryMapFlag)
 
    uchar *map(qint64 offset, qint64 size, MemoryMapFlags flags = NoOptions);
    bool unmap(uchar *address);
 
    QDateTime fileTime(QFileDevice::FileTime time) const;
    bool setFileTime(const QDateTime &newDate, QFileDevice::FileTime fileTime);
 
protected:
    QFileDevice();
#ifdef QT_NO_QOBJECT
    QFileDevice(QFileDevicePrivate &dd);
#else
    explicit QFileDevice(QObject *parent);
    QFileDevice(QFileDevicePrivate &dd, QObject *parent = nullptr);
#endif
 
    qint64 readData(char *data, qint64 maxlen) override;
    qint64 writeData(const char *data, qint64 len) override;
    qint64 readLineData(char *data, qint64 maxlen) override;
 
private:
    Q_DISABLE_COPY(QFileDevice)
};
 
Q_DECLARE_OPERATORS_FOR_FLAGS(QFileDevice::Permissions)
Q_DECLARE_OPERATORS_FOR_FLAGS(QFileDevice::FileHandleFlags)
Q_DECLARE_OPERATORS_FOR_FLAGS(QFileDevice::MemoryMapFlags)
 
QT_END_NAMESPACE
 
#endif // QFILEDEVICE_H