ladybird/Kernel/Devices/ZeroDevice.cpp
Andreas Kling 11eee67b85 Kernel: Make self-contained locking smart pointers their own classes
Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:

- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable

This patch renames the Kernel classes so that they can coexist with
the original AK classes:

- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable

The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.
2022-08-20 17:20:43 +02:00

45 lines
1 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Memory.h>
#include <Kernel/Devices/DeviceManagement.h>
#include <Kernel/Devices/ZeroDevice.h>
#include <Kernel/Sections.h>
namespace Kernel {
UNMAP_AFTER_INIT NonnullLockRefPtr<ZeroDevice> ZeroDevice::must_create()
{
auto zero_device_or_error = DeviceManagement::try_create_device<ZeroDevice>();
// FIXME: Find a way to propagate errors
VERIFY(!zero_device_or_error.is_error());
return zero_device_or_error.release_value();
}
UNMAP_AFTER_INIT ZeroDevice::ZeroDevice()
: CharacterDevice(1, 5)
{
}
UNMAP_AFTER_INIT ZeroDevice::~ZeroDevice() = default;
bool ZeroDevice::can_read(OpenFileDescription const&, u64) const
{
return true;
}
ErrorOr<size_t> ZeroDevice::read(OpenFileDescription&, u64, UserOrKernelBuffer& buffer, size_t size)
{
TRY(buffer.memset(0, size));
return size;
}
ErrorOr<size_t> ZeroDevice::write(OpenFileDescription&, u64, UserOrKernelBuffer const&, size_t size)
{
return size;
}
}