ladybird/Kernel/Devices/ZeroDevice.cpp
Daniel Bertalan 2a5d9a6944 Kernel: Fix adopt_ref_if_nonnull(new T).release_nonnull() pattern
This does the exact thing as `adopt_ref`, which is a recent addition to
AK.

Note that pointers returned by a bare new (without `nothrow`) are
guaranteed not to return null, so they can safely be converted into
references.
2021-06-29 22:57:52 +04:30

46 lines
906 B
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Memory.h>
#include <AK/StdLibExtras.h>
#include <Kernel/Devices/ZeroDevice.h>
#include <Kernel/Panic.h>
#include <Kernel/Sections.h>
namespace Kernel {
UNMAP_AFTER_INIT NonnullRefPtr<ZeroDevice> ZeroDevice::must_create()
{
return adopt_ref(*new ZeroDevice);
}
UNMAP_AFTER_INIT ZeroDevice::ZeroDevice()
: CharacterDevice(1, 5)
{
}
UNMAP_AFTER_INIT ZeroDevice::~ZeroDevice()
{
}
bool ZeroDevice::can_read(const FileDescription&, size_t) const
{
return true;
}
KResultOr<size_t> ZeroDevice::read(FileDescription&, u64, UserOrKernelBuffer& buffer, size_t size)
{
if (!buffer.memset(0, size))
return EFAULT;
return size;
}
KResultOr<size_t> ZeroDevice::write(FileDescription&, u64, const UserOrKernelBuffer&, size_t size)
{
return size;
}
}