ZeroDevice.cpp 851 B

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  1. /*
  2. * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
  3. *
  4. * SPDX-License-Identifier: BSD-2-Clause
  5. */
  6. #include <AK/Memory.h>
  7. #include <Kernel/Devices/ZeroDevice.h>
  8. #include <Kernel/Sections.h>
  9. namespace Kernel {
  10. UNMAP_AFTER_INIT NonnullRefPtr<ZeroDevice> ZeroDevice::must_create()
  11. {
  12. return adopt_ref(*new ZeroDevice);
  13. }
  14. UNMAP_AFTER_INIT ZeroDevice::ZeroDevice()
  15. : CharacterDevice(1, 5)
  16. {
  17. }
  18. UNMAP_AFTER_INIT ZeroDevice::~ZeroDevice()
  19. {
  20. }
  21. bool ZeroDevice::can_read(const FileDescription&, size_t) const
  22. {
  23. return true;
  24. }
  25. KResultOr<size_t> ZeroDevice::read(FileDescription&, u64, UserOrKernelBuffer& buffer, size_t size)
  26. {
  27. if (!buffer.memset(0, size))
  28. return EFAULT;
  29. return size;
  30. }
  31. KResultOr<size_t> ZeroDevice::write(FileDescription&, u64, const UserOrKernelBuffer&, size_t size)
  32. {
  33. return size;
  34. }
  35. }