[MHR-36] Finished ticket.

Signed-off-by: Amlal <amlal@zka.com>

3 files changed, 83 insertions, 10 deletions

diff --git a/Kernel/KernelKit/User.hxx b/Kernel/KernelKit/User.hxx
index aa0901ac..02ba475d 100644
--- a/Kernel/KernelKit/User.hxx
+++ b/Kernel/KernelKit/User.hxx
@@ -26,16 +26,16 @@ namespace Kernel
 {
 	enum class RingKind
 	{
-		kRingStdUser	 = 1,
-		kRingSuperUser	 = 2,
+		kRingStdUser   = 1,
+		kRingSuperUser = 2,
 		kRingGuestUser = 5,
-		kRingCount = 5,
+		kRingCount	   = 5,
 	};
 
 	class User final
 	{
 	public:
-	    explicit User() = default;
+		explicit User() = default;
 
 		User(const Int32& sel, const Char* userName);
 		User(const RingKind& kind, const Char* userName);
@@ -50,16 +50,77 @@ namespace Kernel
 		bool operator!=(const User& lhs);
 
 	public:
-		const RingKind& Ring() noexcept;
+		/// @brief Getters.
+		const RingKind&	 Ring() noexcept;
 		const StringView Name() noexcept;
 
+		Bool IsStdUser() noexcept;
+		Bool IsSuperUser() noexcept;
+
 	private:
-		RingKind fRing{RingKind::kRingStdUser};
+		RingKind   fRing{RingKind::kRingStdUser};
 		StringView fUserName{kMaxUserNameLen};
-
 	};
 
-	inline User* cRootUser = nullptr;
+	class UserView final
+	{
+		UserView()	= default;
+		~UserView() = default;
+
+		User* fCurrentUser		 = nullptr;
+		User* fLastLoggedOffUser = nullptr;
+
+	public:
+		User* fRootUser = nullptr;
+
+	public:
+		NEWOS_COPY_DELETE(UserView);
+
+		STATIC UserView* The() noexcept
+		{
+			UserView* view = nullptr;
+
+			if (!view)
+				view = new UserView();
+
+			return view;
+		}
+
+		Void LogIn(User* user) noexcept
+		{
+			if (fCurrentUser)
+			{
+				if (!fLastLoggedOffUser)
+				{
+					fLastLoggedOffUser = fCurrentUser;
+				}
+				else
+				{
+					this->LogOff();
+				}
+			}
+
+			fCurrentUser = user;
+		}
+
+		Void LogOff() noexcept
+		{
+			if (!fCurrentUser)
+				return;
+
+			// an illegal operation just occured, we can't risk more.
+			if (fCurrentUser == fRootUser)
+			{
+			    ke_stop(RUNTIME_CHECK_BOOTSTRAP);
+			}
+
+			if (fLastLoggedOffUser)
+				delete fLastLoggedOffUser;
+
+			fLastLoggedOffUser = nullptr;
+			fLastLoggedOffUser = fCurrentUser;
+		}
+	};
 } // namespace Kernel
 
 #endif /* ifndef _INC_PERMISSION_SEL_HXX_ */
diff --git a/Kernel/Sources/Main.cxx b/Kernel/Sources/Main.cxx
index 950a8e48..0f835adc 100644
--- a/Kernel/Sources/Main.cxx
+++ b/Kernel/Sources/Main.cxx
@@ -189,8 +189,10 @@ namespace Kernel::Detail
 	STATIC Kernel::Void ke_user_switch(Kernel::Void)
 	{
 
-		Kernel::cRootUser = new User(RingKind::kRingSuperUser, kSuperUser);
-		Kernel::kcout << "newoskrnl: logged in as: " << Kernel::cRootUser->Name().CData() << Kernel::endl;
+		Kernel::UserView::The()->fRootUser = new User(RingKind::kRingSuperUser, kSuperUser);
+		Kernel::kcout << "newoskrnl: logged in as: " << Kernel::UserView::The()->fRootUser->Name().CData() << Kernel::endl;
+
+		Kernel::UserView::The()->LogIn(Kernel::UserView::The()->fRootUser);
 
 		Kernel::kcout << "newoskrnl: " << cKernelVersion.GetKey().CData() << ": " << Kernel::number(cKernelVersion.GetValue()) << Kernel::endl;
 	}
diff --git a/Kernel/Sources/User.cxx b/Kernel/Sources/User.cxx
index 1deac5be..68d0d5be 100644
--- a/Kernel/Sources/User.cxx
+++ b/Kernel/Sources/User.cxx
@@ -51,4 +51,14 @@ namespace Kernel
 	{
 		return this->fRing;
 	}
+
+	Bool User::IsStdUser() noexcept
+	{
+		return this->Ring() == RingKind::kRingStdUser;
+	}
+
+	Bool User::IsSuperUser() noexcept
+	{
+		return this->Ring() == RingKind::kRingSuperUser;
+	}
 } // namespace Kernel