Changeset 3 for trunk/UKernel.pas

Timestamp:

Nov 22, 2014, 11:50:49 PM (9 years ago)

Author:

chronos

Message:

• Added: Application is executed as Task by Scheduler. OS threads is used for scheduler for efficient execution.

File:

• trunk/UKernel.pas (modified) (6 diffs)

trunk/UKernel.pas

@@ -9 +9 @@
 
 type
+  TEvent = procedure of object;
 
   TTaskState = (tsStopped, tsRunning, tsSuspended);
 
-  TTask = class
+  { TTask }
+
+  TTask = class(TNamedObject)
     Name: string;
     State: TTaskState;
+    EntryPoint: TEvent;
+    constructor Create; virtual;
   end;
 
-  TTasks = class(TObjectList)
+  TTaskClass = class of TTask;
 
+  { TScheduler }
+
+  TScheduler = class
+    TaskClass: TTaskClass;
+    Tasks: TNamedObjectList; // TList<TTask>
+    Running: Boolean;
+    procedure Start; virtual;
+    procedure Stop;
+    function AddTask(Name: string; EntryPoint: TEvent): TTask; virtual;
+    constructor Create; virtual;
+    destructor Destroy; override;
   end;
 
-  TScheduler = class
-    Tasks: TTasks;
-  end;
+  TSchedulerClass = class of TScheduler;
 
   TDrive = class(TNamedObject)
@@ -34 +48 @@
     Apps: TNamedObjectList; // TList<TApp>
     Drives: TNamedObjectList; // TList<TDrive>
-    procedure Execute(AFile: TFile);
+    Scheduler: TScheduler;
+    SchedulerClass: TSchedulerClass;
+    FileSystemClass: TFileSystemClass;
+    procedure AppExecute(AFile: TFile);
     procedure Init;
     procedure Run;
@@ -43 +60 @@
 implementation
 
-uses
-  UPlatformBase;
+{ TTask }
+
+constructor TTask.Create;
+begin
+
+end;
+
+{ TScheduler }
+
+procedure TScheduler.Start;
+begin
+  Running := True;
+end;
+
+procedure TScheduler.Stop;
+begin
+  Running := False;
+end;
+
+function TScheduler.AddTask(Name: string; EntryPoint: TEvent): TTask;
+var
+  NewTask: TTask;
+begin
+  NewTask := TaskClass.Create;
+  NewTask.Name := Name;
+  NewTask.EntryPoint := EntryPoint;
+  Tasks.Add(NewTask);
+  Result := NewTask;
+end;
+
+constructor TScheduler.Create;
+begin
+  TaskClass := TTask;
+  Tasks := TNamedObjectList.Create;
+end;
+
+destructor TScheduler.Destroy;
+begin
+  if Running then Stop;
+  Tasks.Free;
+  inherited Destroy;
+end;
 
 { TKernel }
 
-procedure TKernel.Execute(AFile: TFile);
+procedure TKernel.AppExecute(AFile: TFile);
 var
   App: TApp;
 begin
   App := TApp(Apps.FindByName(AFile.Name));
-  if Assigned(App) then App.Run
-    else raise Exception.Create('Application ''' + AFile.Name + ''' no found');
+  if Assigned(App) then begin
+    Scheduler.AddTask(App.Name, App.Run);
+  end else raise Exception.Create('Application ''' + AFile.Name + ''' no found');
 end;
 
@@ -62 +120 @@
   NewFile: TFile;
 begin
+  Scheduler.Free;
+  Scheduler := SchedulerClass.Create;
+
   NewDrive := TDrive.Create;
   NewDrive.Name := 'System';
-  NewDrive.FileSystem := TBaseFileSystem.Create;
+  NewDrive.FileSystem := FileSystemClass.Create;
   Drives.Add(NewDrive);
 
@@ -83 +144 @@
     SystemFileSystem := SystemDrive.FileSystem;
     AppFile := TFile(SystemFileSystem.TopDirectory.Items.FindByName('Clock'));
-    if Assigned(AppFile) then Execute(AppFile)
+    if Assigned(AppFile) then AppExecute(AppFile)
       else raise Exception.Create('Cannot start first application');
+    Scheduler.Start;
   end else raise Exception.Create('Missing System drive');
 end;
@@ -92 +154 @@
   Drives := TNamedObjectList.Create;
   Apps := TNamedObjectList.Create;
+  Scheduler := TScheduler.Create;
 end;
 
 destructor TKernel.Destroy;
 begin
+  Scheduler.Free;
   Apps.Free;
   Drives.Free;