ladybird/Kernel/Devices/ZeroDevice.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

41 lines
825 B
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include "ZeroDevice.h"
#include <AK/Memory.h>
#include <AK/StdLibExtras.h>
namespace Kernel {
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)
{
ssize_t count = min(static_cast<size_t>(PAGE_SIZE), size);
if (!buffer.memset(0, count))
return EFAULT;
return count;
}
KResultOr<size_t> ZeroDevice::write(FileDescription&, u64, const UserOrKernelBuffer&, size_t size)
{
return min(static_cast<size_t>(PAGE_SIZE), size);
}
}