text: /*
   * Copyright (c) 2018-2020, krishpranav <krisna.pranav@gmail.com>
   *
   * SPDX-License-Identifier: BSD-2-Clause
   */
  
  #pragma once
  
  #include <AK/Assertions.h>
  #include <AK/StdLibExtras.h>
  #include <AK/Types.h>
  
  namespace AK {
  
  // HACK: This is just here to make syntax highlighting work in Qt Creator.
  //       Once it supports C++20 concepts, we can remove this.
  #if defined(__cpp_concepts) && !defined(__COVERITY__)
  template<typename T>
  concept PointerTypeName = IsPointer<T>;
  template<PointerTypeName T>
  #else
  template<typename T, typename EnableIf<IsPointer<T>, int>::Type = 0>
  #endif
  
  class Userspace {
  public:
      Userspace() = default;
  
      operator bool() const { return m_ptr; }
      operator FlatPtr() const { return (FlatPtr)m_ptr; }
  
      // Disable default implementations that would use surprising integer promotion.
      bool operator==(const Userspace&) const = delete;
      bool operator<=(const Userspace&) const = delete;
      bool operator>=(const Userspace&) const = delete;
      bool operator<(const Userspace&) const = delete;
      bool operator>(const Userspace&) const = delete;
  
  #ifdef KERNEL
      Userspace(FlatPtr ptr)
          : m_ptr(ptr)
      {
      }
  
      FlatPtr ptr() const { return m_ptr; }
      T unsafe_userspace_ptr() const { return (T)m_ptr; }
  #else
      Userspace(T ptr)
          : m_ptr(ptr)
      {
      }
  
      T ptr() const { return m_ptr; }
  #endif
  
  private:
  #ifdef KERNEL
      FlatPtr m_ptr { 0 };
  #else
      T m_ptr { nullptr };
  #endif
  };
  
  template<typename T, typename U>
  inline Userspace<T> static_ptr_cast(const Userspace<U>& ptr)
  {
  #ifdef KERNEL
      auto casted_ptr = static_cast<T>(ptr.unsafe_userspace_ptr());
  #else
      auto casted_ptr = static_cast<T>(ptr.ptr());
  #endif
      return Userspace<T>((FlatPtr)casted_ptr);
  }
  
  }
  
  using AK::static_ptr_cast;
  using AK::Userspace;
  