Kernel/Devices/ZeroDevice.h


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/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include "CharacterDevice.h"

namespace Kernel {

class ZeroDevice final : public CharacterDevice {
    AK_MAKE_ETERNAL
public:
    static NonnullRefPtr<ZeroDevice> must_create();
    virtual ~ZeroDevice() override;

    // ^Device
    virtual mode_t required_mode() const override { return 0666; }
    virtual String device_name() const override { return "zero"; }

private:
    ZeroDevice();
    // ^CharacterDevice
    virtual KResultOr<size_t> read(FileDescription&, u64, UserOrKernelBuffer&, size_t) override;
    virtual KResultOr<size_t> write(FileDescription&, u64, const UserOrKernelBuffer&, size_t) override;
    virtual bool can_read(const FileDescription&, size_t) const override;
    virtual bool can_write(const FileDescription&, size_t) const override { return true; }
    virtual const char* class_name() const override { return "ZeroDevice"; }
};

}