ladybird/Kernel/Devices/NullDevice.cpp
Brian Gianforcaro 1682f0b760 Everything: Move to SPDX license identifiers in all files.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.

See: https://spdx.dev/resources/use/#identifiers

This was done with the `ambr` search and replace tool.

 ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
2021-04-22 11:22:27 +02:00

49 lines
882 B
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "NullDevice.h"
#include <AK/Singleton.h>
#include <AK/StdLibExtras.h>
namespace Kernel {
static AK::Singleton<NullDevice> s_the;
UNMAP_AFTER_INIT void NullDevice::initialize()
{
s_the.ensure_instance();
}
NullDevice& NullDevice::the()
{
return *s_the;
}
UNMAP_AFTER_INIT NullDevice::NullDevice()
: CharacterDevice(1, 3)
{
}
UNMAP_AFTER_INIT NullDevice::~NullDevice()
{
}
bool NullDevice::can_read(const FileDescription&, size_t) const
{
return true;
}
KResultOr<size_t> NullDevice::read(FileDescription&, u64, UserOrKernelBuffer&, size_t)
{
return 0;
}
KResultOr<size_t> NullDevice::write(FileDescription&, u64, const UserOrKernelBuffer&, size_t buffer_size)
{
return min(static_cast<size_t>(PAGE_SIZE), buffer_size);
}
}