
Instead of doing so in the constructor, let's do immediately after the constructor, so we can safely pass a reference of a Device, so the SysFSDeviceComponent constructor can use that object to identify whether it's a block device or a character device. This allows to us to not hold a device in SysFSDeviceComponent with a RefPtr. Also, we also call the before_removing method in both SlavePTY::unref and File::unref, so because Device has that method being overrided, it can ensure the device is removed always cleanly.
46 lines
1,006 B
C++
46 lines
1,006 B
C++
/*
|
|
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <AK/Memory.h>
|
|
#include <Kernel/Devices/ZeroDevice.h>
|
|
#include <Kernel/Sections.h>
|
|
|
|
namespace Kernel {
|
|
|
|
UNMAP_AFTER_INIT NonnullRefPtr<ZeroDevice> ZeroDevice::must_create()
|
|
{
|
|
auto zero_device_or_error = 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()
|
|
{
|
|
}
|
|
|
|
bool ZeroDevice::can_read(const OpenFileDescription&, size_t) const
|
|
{
|
|
return true;
|
|
}
|
|
|
|
KResultOr<size_t> ZeroDevice::read(OpenFileDescription&, u64, UserOrKernelBuffer& buffer, size_t size)
|
|
{
|
|
TRY(buffer.memset(0, size));
|
|
return size;
|
|
}
|
|
|
|
KResultOr<size_t> ZeroDevice::write(OpenFileDescription&, u64, const UserOrKernelBuffer&, size_t size)
|
|
{
|
|
return size;
|
|
}
|
|
|
|
}
|