text: /*
   * Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
   *
   * SPDX-License-Identifier: BSD-2-Clause
   */
  
  #pragma once
  
  #include <AK/Badge.h>
  #include <AK/Error.h>
  #include <AK/NonnullRefPtrVector.h>
  #include <AK/OwnPtr.h>
  #include <AK/RefPtr.h>
  #include <AK/Time.h>
  #include <AK/Types.h>
  #include <Kernel/API/DeviceEvent.h>
  #include <Kernel/API/TimePage.h>
  #include <Kernel/Arch/RegisterState.h>
  #include <Kernel/Devices/CharacterDevice.h>
  #include <Kernel/Devices/ConsoleDevice.h>
  #include <Kernel/Devices/Device.h>
  #include <Kernel/Devices/DeviceControlDevice.h>
  #include <Kernel/Devices/NullDevice.h>
  #include <Kernel/UnixTypes.h>
  
  namespace Kernel {
  
  class DeviceManagement {
  
  public:
      DeviceManagement();
      static void initialize();
      static DeviceManagement& the();
      void attach_null_device(NullDevice const&);
  
      void attach_device_control_device(DeviceControlDevice const&);
  
      bool is_console_device_attached() const { return !m_console_device.is_null(); }
      void attach_console_device(ConsoleDevice const&);
  
      // FIXME: Once we have a singleton for managing many sound cards, remove this from here
      void attach_audio_device(CharacterDevice const&);
  
      Optional<DeviceEvent> dequeue_top_device_event(Badge<DeviceControlDevice>);
  
      void after_inserting_device(Badge<Device>, Device&);
      void before_device_removal(Badge<Device>, Device&);
  
      void for_each(Function<void(Device&)>);
      Device* get_device(MajorNumber major, MinorNumber minor);
  
      NullDevice const& null_device() const;
      NullDevice& null_device();
  
      ConsoleDevice const& console_device() const;
      ConsoleDevice& console_device();
  
      template<typename DeviceType, typename... Args>
      static inline ErrorOr<NonnullRefPtr<DeviceType>> try_create_device(Args&&... args) requires(requires(Args... args) { DeviceType::try_create(args...); })
      {
          auto device = TRY(DeviceType::try_create(forward<Args>(args)...));
          device->after_inserting();
          return device;
      }
  
      template<typename DeviceType, typename... Args>
      static inline ErrorOr<NonnullRefPtr<DeviceType>> try_create_device(Args&&... args)
      {
          auto device = TRY(adopt_nonnull_ref_or_enomem(new (nothrow) DeviceType(forward<Args>(args)...)));
          device->after_inserting();
          return device;
      }
  
  private:
      RefPtr<NullDevice> m_null_device;
      RefPtr<ConsoleDevice> m_console_device;
      RefPtr<DeviceControlDevice> m_device_control_device;
      // FIXME: Once we have a singleton for managing many sound cards, remove this from here
      NonnullRefPtrVector<CharacterDevice, 1> m_audio_devices;
      MutexProtected<HashMap<u64, Device*>> m_devices;
  
      mutable Spinlock m_event_queue_lock;
      CircularQueue<DeviceEvent, 100> m_event_queue;
  };
  
  }
  