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-rw-r--r--Kernel/Devices/Generic/NullDevice.cpp44
1 files changed, 44 insertions, 0 deletions
diff --git a/Kernel/Devices/Generic/NullDevice.cpp b/Kernel/Devices/Generic/NullDevice.cpp
new file mode 100644
index 0000000000..b82e4ae072
--- /dev/null
+++ b/Kernel/Devices/Generic/NullDevice.cpp
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Singleton.h>
+#include <Kernel/Devices/DeviceManagement.h>
+#include <Kernel/Devices/Generic/NullDevice.h>
+#include <Kernel/Sections.h>
+
+namespace Kernel {
+
+UNMAP_AFTER_INIT NonnullLockRefPtr<NullDevice> NullDevice::must_initialize()
+{
+ auto null_device_or_error = DeviceManagement::try_create_device<NullDevice>();
+ // FIXME: Find a way to propagate errors
+ VERIFY(!null_device_or_error.is_error());
+ return null_device_or_error.release_value();
+}
+
+UNMAP_AFTER_INIT NullDevice::NullDevice()
+ : CharacterDevice(1, 3)
+{
+}
+
+UNMAP_AFTER_INIT NullDevice::~NullDevice() = default;
+
+bool NullDevice::can_read(OpenFileDescription const&, u64) const
+{
+ return true;
+}
+
+ErrorOr<size_t> NullDevice::read(OpenFileDescription&, u64, UserOrKernelBuffer&, size_t)
+{
+ return 0;
+}
+
+ErrorOr<size_t> NullDevice::write(OpenFileDescription&, u64, UserOrKernelBuffer const&, size_t buffer_size)
+{
+ return buffer_size;
+}
+
+}