Kernel: Implement basic random device to /dev/random

kernel/include/kernel/Device/DeviceNumbers.h

@@ -12,6 +12,7 @@ namespace Kernel
 		PTSMaster,
 		Null,
 		Zero,
+		Random,
 		Debug,
 		Keyboard,
 		Mouse,

kernel/include/kernel/Device/RandomDevice.h

@@ -0,0 +1,32 @@
+#include <kernel/Device/Device.h>
+
+namespace Kernel
+{
+
+	class RandomDevice : public CharacterDevice
+	{
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<RandomDevice>> create(mode_t, uid_t, gid_t);
+
+		virtual dev_t rdev() const override { return m_rdev; }
+
+		virtual BAN::StringView name() const override { return "random"_sv; }
+
+	protected:
+		RandomDevice(mode_t mode, uid_t uid, gid_t gid, dev_t rdev)
+			: CharacterDevice(mode, uid, gid)
+			, m_rdev(rdev)
+		{ }
+
+		virtual BAN::ErrorOr<size_t> read_impl(off_t, BAN::ByteSpan) override;
+		virtual BAN::ErrorOr<size_t> write_impl(off_t, BAN::ConstByteSpan buffer) override { return buffer.size(); };
+
+		virtual bool can_read_impl() const override { return true; }
+		virtual bool can_write_impl() const override { return false; }
+		virtual bool has_error_impl() const override { return false; }
+
+	private:
+		const dev_t m_rdev;
+	};
+
+}