Indy/Lib/Core/IdThreadComponent.pas

{
  $Project$
  $Workfile$
  $Revision$
  $DateUTC$
  $Id$

  This file is part of the Indy (Internet Direct) project, and is offered
  under the dual-licensing agreement described on the Indy website.
  (http://www.indyproject.org/)

  Copyright:
   (c) 1993-2005, Chad Z. Hower and the Indy Pit Crew. All rights reserved.
}
{
  $Log$
}
{
  Rev 1.13    9/30/2004 2:26:04 PM  BGooijen
  wrong property was referenced

  Rev 1.12    2004.02.03 4:17:12 PM  czhower
  For unit name changes.

  Rev 1.11    2004.01.20 10:03:38 PM  czhower
  InitComponent

  Rev 1.10    09.11.2003 14:05:52  ARybin
  AV

  Rev 1.9    08.11.2003 20:03:20  ARybin
  run-time active bug

    Rev 1.8    10/15/2003 8:48:58 PM  DSiders
  Added resource strings for exceptions raised when setting thread component
  properties.

  Rev 1.7    2003.10.11 9:58:04 PM  czhower
  Several bug fixes

  Rev 1.6    2003.10.11 5:51:54 PM  czhower
  -VCL fixes for servers
  -Chain suport for servers (Super core)
  -Scheduler upgrades
  -Full yarn support

  Rev 1.5    2003.09.30 7:48:02 PM  czhower
  Fixed Loop and ThreadName

  Rev 1.4    9/18/2003 07:40:52 PM  JPMugaas
  Removed IdGlobal.

  Rev 1.3    9/16/2003 04:47:22 PM  JPMugaas
  Made some code follow the Indy conventions so it's easier to debug.

  Rev 1.2    2003.07.01 4:14:38 PM  czhower
  ThreadName and Loop added. Other bugs fixed.

  Rev 1.1    06.03.2003 12:16:52  ARybin
  adapted for new IdThread

  Rev 1.0    11/13/2002 08:03:06 AM  JPMugaas

  2002-05-03 -Andrew P.Rybin
   -Stéphane Grobéty (Fulgan) suggestion: component is Data owner, don't FreeAndNIL Data property
   -special TThread.OnTerminate support (it is sync-event)

  2002-05-23 -APR
   -right support for Thread terminate
}

unit IdThreadComponent;

{
 UnitName: IdThreadComponent
 Author:   Andrew P.Rybin [[email protected]]
 Creation: 12.03.2002
 Version:  0.1.0
 Purpose:
 History:  Based on my TmcThread
}

interface

{$I IdCompilerDefines.inc}
//Put FPC into Delphi mode

uses
  Classes,
  IdBaseComponent, IdException, IdGlobal, IdThread, SysUtils;

const
  IdThreadComponentDefaultPriority = tpNormal;
  IdThreadComponentDefaultStopMode = smTerminate;

type
  TIdThreadComponent = class;

  TIdExceptionThreadComponentEvent = procedure(Sender: TIdThreadComponent; AException: Exception) of object;
  TIdExceptionThreadComponentEventEx = procedure(Sender: TIdThreadComponent; AException: Exception; var VHandled: Boolean) of object;
  TIdNotifyThreadComponentEvent = procedure(Sender: TIdThreadComponent) of object;
  //TIdSynchronizeThreadComponentEvent = procedure(Sender: TIdThreadComponent; AData: Pointer) of object;

  TIdThreadComponent = class(TIdBaseComponent)
  protected
    FActive: Boolean;
    FLoop: Boolean;
    FPriority : TIdThreadPriority;
    FStopMode : TIdThreadStopMode;
    FThread: TIdThread;
    FThreadName: string;
    //
    FOnAfterExecute: TIdNotifyThreadComponentEvent;
    FOnAfterRun: TIdNotifyThreadComponentEvent;
    FOnBeforeExecute: TIdNotifyThreadComponentEvent;
    FOnBeforeRun: TIdNotifyThreadComponentEvent;
    FOnCleanup: TIdNotifyThreadComponentEvent;
    FOnException: TIdExceptionThreadComponentEvent;
    FOnRun: TIdNotifyThreadComponentEvent;
    FOnStopped: TIdNotifyThreadComponentEvent;
    FOnTerminate: TIdNotifyThreadComponentEvent;
    FOnHandleRunException: TIdExceptionThreadComponentEventEx;
    //
    {$IFDEF INT_THREAD_PRIORITY}
    procedure DefineProperties(Filer: TFiler); override;
    procedure ReadPriority(Reader: TReader);
    procedure WritePriority(Writer: TWriter);
    {$ENDIF}
    procedure DoAfterExecute; virtual;
    procedure DoAfterRun; virtual;
    procedure DoBeforeExecute; virtual;
    procedure DoBeforeRun; virtual;
    procedure DoCleanup; virtual;
    procedure DoException(AThread: TIdThread; AException: Exception); virtual; //thev
    function DoHandleRunException(AException: Exception): Boolean; virtual;
    procedure DoRun; virtual;
    procedure DoStopped(AThread: TIdThread); virtual; //thev
    procedure DoTerminate(Sender: TObject); virtual; //thev
    function GetActive: Boolean;
    {$IFDEF USE_OBJECT_ARC}
    // When ARC is enabled, object references MUST be valid objects.
    // It is common for users to store non-object values, though, so
    // we will provide separate properties for those purposes
    //
    // TODO; use TValue instead of separating them
    //
    function GetDataObject: TObject;
    function GetDataValue: PtrInt;
    {$ELSE}
    function GetData: TObject;
    {$ENDIF}
    function GetHandle: TIdThreadHandle;
    function GetPriority: TIdThreadPriority;
    function GetReturnValue: Integer;
    function GetStopMode: TIdThreadStopMode;
    function GetStopped: Boolean;
    function GetSuspended: Boolean;
    function GetTerminatingException: string;
    function GetTerminatingExceptionClass: TClass;
    function GetTerminated: Boolean;
    procedure InitComponent; override;
    function IsRunning: Boolean;
    procedure Loaded; override;
    procedure SetActive(const AValue: Boolean); virtual;
    {$IFDEF USE_OBJECT_ARC}
    procedure SetDataObject(const AValue: TObject);
    procedure SetDataValue(const AValue: PtrInt);
    {$ELSE}
    procedure SetData(const AValue: TObject);
    {$ENDIF}
    procedure SetLoop(const AValue: Boolean);
    procedure SetThreadName(const AValue: string);
    procedure SetOnTerminate(const AValue: TIdNotifyThreadComponentEvent);
    procedure SetPriority(const AValue: TIdThreadPriority);
    procedure SetReturnValue(const AValue: Integer);
    procedure SetStopMode(const AValue: TIdThreadStopMode);
  public
    destructor Destroy; override;
    procedure Start; virtual;
    procedure Stop; virtual;
    procedure Synchronize(AMethod: TThreadMethod);
    procedure Terminate; virtual;
    procedure TerminateAndWaitFor; virtual;
    function WaitFor: UInt32;
    // Properties
    {$IFDEF USE_OBJECT_ARC}
    property DataObject: TObject read GetDataObject write SetDataObject;
    property DataValue: PtrInt read GetDataValue write SetDataValue;
    {$ELSE}
    property Data: TObject read GetData write SetData;
    {$ENDIF}
    property Handle: TIdThreadHandle read GetHandle;
    property ReturnValue: Integer read GetReturnValue write SetReturnValue;
    property Stopped: Boolean read GetStopped;
    property Suspended: Boolean read GetSuspended;
    property TerminatingException: string read GetTerminatingException;
    property TerminatingExceptionClass: TClass read GetTerminatingExceptionClass;
    property Terminated: Boolean read GetTerminated;
    {$IFDEF INT_THREAD_PRIORITY}
    property Priority: TIdThreadPriority read GetPriority write SetPriority;
    {$ENDIF}
  published
    property Active: Boolean read GetActive write SetActive;
    property Loop: Boolean read FLoop write SetLoop;
    {$IFNDEF INT_THREAD_PRIORITY}
    property Priority: TIdThreadPriority read GetPriority write SetPriority;
    {$ENDIF}
    property StopMode: TIdThreadStopMode read GetStopMode write SetStopMode;
    property ThreadName: string read FThreadName write SetThreadName;
    // Events
    property OnAfterExecute: TIdNotifyThreadComponentEvent read FOnAfterExecute write FOnAfterExecute;
    property OnAfterRun: TIdNotifyThreadComponentEvent read FOnAfterRun write FOnAfterRun;
    property OnBeforeExecute: TIdNotifyThreadComponentEvent read FOnBeforeExecute write FOnBeforeExecute;
    property OnBeforeRun: TIdNotifyThreadComponentEvent read FOnBeforeRun write FOnBeforeRun;
    property OnCleanup: TIdNotifyThreadComponentEvent read FOnCleanup write FOnCleanup;
    property OnException: TIdExceptionThreadComponentEvent read FOnException write FOnException;
    property OnHandleRunException: TIdExceptionThreadComponentEventEx
     read FOnHandleRunException write FOnHandleRunException;
    property OnRun: TIdNotifyThreadComponentEvent read FOnRun write FOnRun;
    property OnStopped: TIdNotifyThreadComponentEvent read FOnStopped
     write FOnStopped;
    property OnTerminate: TIdNotifyThreadComponentEvent read FOnTerminate
     write SetOnTerminate;
  end;

  //For Component-writers ONLY!
  TIdThreadEx = class(TIdThread)
  protected
    FThreadComponent: TIdThreadComponent;
    //
    procedure AfterRun; override;
    procedure AfterExecute; override;
    procedure BeforeExecute; override;
    procedure BeforeRun; override;
    procedure Cleanup; override;
    function  HandleRunException(AException: Exception): Boolean; override;
    procedure Run; override;
  public
    constructor Create(AThreadComponent: TIdThreadComponent); reintroduce;
  end;

implementation

uses
  IdResourceStringsCore;

{ TIdThreadEx }

procedure TIdThreadEx.AfterExecute;
begin
  try
    FThreadComponent.DoAfterExecute;
  finally
    FThreadComponent.FActive := FALSE;
  end;
end;

procedure TIdThreadEx.AfterRun;
begin
  FThreadComponent.DoAfterRun;
end;

procedure TIdThreadEx.BeforeExecute;
begin
  FThreadComponent.DoBeforeExecute;
end;

procedure TIdThreadEx.BeforeRun;
begin
  FThreadComponent.DoBeforeRun;
end;

procedure TIdThreadEx.Cleanup;
begin
  inherited Cleanup;
  FThreadComponent.DoCleanup;
end;

constructor TIdThreadEx.Create(AThreadComponent: TIdThreadComponent);
begin
  inherited Create(True, AThreadComponent.Loop, iif(AThreadComponent.ThreadName = ''
   , AThreadComponent.Name, AThreadComponent.ThreadName));
  Exclude(FOptions, itoDataOwner); //TIdThreadComponent is data owner
  FThreadComponent := AThreadComponent;
  FOnException := FThreadComponent.DoException;
  FOnStopped := FThreadComponent.DoStopped;
end;

function TIdThreadEx.HandleRunException(AException: Exception): Boolean;
begin
  Result := FThreadComponent.DoHandleRunException(AException);
end;

procedure TIdThreadEx.Run;
begin
  FThreadComponent.DoRun;
end;

{ TIdThreadComponent }

{$IFDEF INT_THREAD_PRIORITY}
procedure TIdThreadComponent.DefineProperties(Filer: TFiler);
begin
  inherited;
  Filer.DefineProperty('Priority', ReadPriority, WritePriority, FPriority <> tpNormal);
end;

procedure TIdThreadComponent.ReadPriority(Reader: TReader);
const
  PriorityStrings: array[0..6] of string = ('tpIdle', 'tpLowest', 'tpLower', 'tpNormal', 'tpHigher', 'tpHighest', 'tpTimeCritical'); {do not localize}
var
  Value: Integer;
begin
  if Reader.NextValue = vaIdent then
  begin
    // an older DFM that stored TThreadPriority as enum value names is being read, so convert to integer ...
    case PosInStrArray(Reader.ReadIdent, PriorityStrings, False) of
      0: Value := tpIdle;
      1: Value := tpLowest;
      2: Value := tpLower;
      3: Value := tpNormal;
      4: Value := tpHigher;
      5: Value := tpHighest;
      6: Value := tpTimeCritical;
    else
      Value := tpNormal;
    end;
  end else
  begin
    Value := Reader.ReadInteger;
    if Value < -20 then begin
      Value := -20;
    end
    else if Value > 19 then begin
      Value := 19;
    end;
  end;
  FPriority := Value;
end;

procedure TIdThreadComponent.WritePriority(Writer: TWriter);
begin
  Writer.WriteInteger(FPriority);
end;
{$ENDIF}

procedure TIdThreadComponent.DoAfterExecute;
begin
  if Assigned(FOnAfterExecute) then
  begin
    FOnAfterExecute(Self);
  end;
end;

procedure TIdThreadComponent.DoAfterRun;
begin
  if Assigned(FOnAfterRun) then
  begin
    FOnAfterRun(Self);
  end;
end;

procedure TIdThreadComponent.DoBeforeExecute;
begin
  if Assigned(FOnBeforeExecute) then
  begin
    FOnBeforeExecute(Self);
  end;
end;

procedure TIdThreadComponent.DoBeforeRun;
begin
  if Assigned(FOnBeforeRun) then
  begin
    FOnBeforeRun(Self);
  end;
end;

procedure TIdThreadComponent.DoCleanup;
begin
  if Assigned(FOnCleanup) then
  begin
    FOnCleanup(Self);
  end;
end;

destructor TIdThreadComponent.Destroy;
begin
  {FThread.TerminateAndWaitFor;}
  //make sure thread is not active before we attempt to destroy it
  if Assigned(FThread) then begin
    FThread.Terminate;
    FThread.Start;//resume for terminate
  end;
  IdDisposeAndNil(FThread);
  inherited Destroy;
end;

procedure TIdThreadComponent.DoException(AThread: TIdThread; AException: Exception);
begin
  if Assigned(FOnException) then begin
    FOnException(Self, AException);
  end;
end;

function TIdThreadComponent.DoHandleRunException(AException: Exception): Boolean;
begin
  Result := False;//not handled
  if Assigned(FOnHandleRunException) then begin
    FOnHandleRunException(Self, AException, Result);
  end;
end;

procedure TIdThreadComponent.DoStopped(AThread: TIdThread);
begin
  if Assigned(FOnStopped) then begin
    FOnStopped(Self);
  end;
end;

procedure TIdThreadComponent.DoTerminate;
begin
  if Assigned(FOnTerminate) then begin
    FOnTerminate(Self);
  end;
end;

{$IFDEF USE_OBJECT_ARC}

function TIdThreadComponent.GetDataObject: TObject;
begin
  Result := FThread.DataObject;
end;

function TIdThreadComponent.GetDataValue: PtrInt;
begin
  Result := FThread.DataValue;
end;

{$ELSE}

function TIdThreadComponent.GetData: TObject;
begin
  Result := FThread.Data;
end;

{$ENDIF}

function TIdThreadComponent.GetHandle: TIdThreadHandle;
begin
  Result := GetThreadHandle(FThread);
end;

function TIdThreadComponent.GetReturnValue: Integer;
begin
  Result := FThread.ReturnValue;
end;

function TIdThreadComponent.GetStopMode: TIdThreadStopMode;
begin
  if Assigned(FThread) then begin
    Result := FThread.StopMode;
  end else begin
    Result := FStopMode;
  end;
end;

function TIdThreadComponent.GetStopped: Boolean;
begin
  if Assigned(FThread) then begin
    Result := FThread.Stopped;
  end else begin
    Result := True;
  end;
end;

function TIdThreadComponent.GetSuspended: Boolean;
begin
  Result := FThread.Suspended;
end;

function TIdThreadComponent.GetTerminated: Boolean;
begin
  if Assigned(FThread) then begin
    Result := FThread.Terminated;
  end else begin
    Result := True;
  end;
end;

function TIdThreadComponent.GetTerminatingException: string;
begin
  Result := FThread.TerminatingException;
end;

function TIdThreadComponent.GetTerminatingExceptionClass: TClass;
begin
  Result := FThread.TerminatingExceptionClass;
end;

procedure TIdThreadComponent.Loaded;
begin
  inherited Loaded;
  // Active = True must not be performed before all other props are loaded
  if Assigned(FThread) and Assigned(OnTerminate) then begin
    FThread.OnTerminate := DoTerminate;
  end;

  if FActive then begin
    // Retoggle for load since we ignore during loading until all properties
    // are ready
    FActive := False;
    Active := True;
  end;
end;

procedure TIdThreadComponent.DoRun;
begin
  if Assigned(FOnRun) then begin
    FOnRun(Self);
  end;
end;

procedure TIdThreadComponent.SetActive(const AValue: Boolean);
begin
  if IsDesignTime or IsLoading then begin
    FActive := AValue;
  end
  else if Active <> AValue then begin
    if AValue then begin
      Start;
    end else begin
      Stop;
    end;
    FActive := AValue;
  end;
end;

{$IFDEF USE_OBJECT_ARC}

procedure TIdThreadComponent.SetDataObject(const AValue: TObject);
begin
// this should not be accessed at design-time.
  FThread.DataObject := AValue;
end;

procedure TIdThreadComponent.SetDataValue(const AValue: PtrInt);
begin
// this should not be accessed at design-time.
  FThread.DataValue := AValue;
end;

{$ELSE}

procedure TIdThreadComponent.SetData(const AValue: TObject);
begin
// this should not be accessed at design-time.
  FThread.Data := AValue;
end;

{$ENDIF}

procedure TIdThreadComponent.SetReturnValue(const AValue: Integer);
begin
// this should not be accessed at design-time.
  FThread.ReturnValue := AValue;
end;

procedure TIdThreadComponent.SetStopMode(const AValue: TIdThreadStopMode);
begin
  if Assigned(FThread) and not FThread.Terminated then begin
    FThread.StopMode := AValue;
  end;
  FStopMode := AValue;
end;

procedure TIdThreadComponent.Start;
begin
  if not IsDesignTime then begin
    if Assigned(FThread) and FThread.Terminated then begin
      IdDisposeAndNil(FThread);
    end;

    if not Assigned(FThread) then begin
      FThread := TIdThreadEx.Create(Self);
    end;

    // MUST read from F variants as thread is now created

    if Assigned(FOnTerminate) then begin
      FThread.OnTerminate := DoTerminate;
    end else begin
      FThread.OnTerminate := nil;
    end;

    FThread.Name := FThreadName;
    FThread.Loop := FLoop;
    FThread.Priority := FPriority;
    FThread.StopMode := FStopMode;

    FThread.Start;
  end;
end;

procedure TIdThreadComponent.Stop;
begin
  if Assigned(FThread) then begin
    FThread.Stop;
  end;
end;

procedure TIdThreadComponent.Synchronize(AMethod: TThreadMethod);
begin
  FThread.Synchronize(AMethod);
end;

procedure TIdThreadComponent.Terminate;
begin
  FThread.Terminate;
end;

procedure TIdThreadComponent.TerminateAndWaitFor;
begin
  FThread.TerminateAndWaitFor;
end;

function TIdThreadComponent.WaitFor: UInt32;
begin
  Result := FThread.WaitFor;
end;

function TIdThreadComponent.GetPriority: TIdThreadPriority;
begin
  if Assigned(FThread) then begin
    Result := FThread.Priority;
  end else begin
    Result := FPriority;
  end;
end;

procedure TIdThreadComponent.SetPriority(const AValue: TIdThreadPriority);
begin
  if Assigned(FThread) then begin
    if not FThread.Terminated then begin
      FThread.Priority := AValue;
    end;
  end;
  FPriority := AValue;
end;

function TIdThreadComponent.GetActive: Boolean;
begin
  if IsDesignTime then begin
    Result := FActive;
  end else begin
    Result := IsRunning;
  end;
end;

procedure TIdThreadComponent.SetOnTerminate(const AValue: TIdNotifyThreadComponentEvent);
begin
  FOnTerminate := AValue;
  if Assigned(FThread) then begin
    if Assigned(AValue) then begin
      FThread.OnTerminate := DoTerminate;
    end else begin
      FThread.OnTerminate := nil;
    end;
  end;
end;

procedure TIdThreadComponent.SetLoop(const AValue: Boolean);
begin
  if IsRunning then begin
    raise EIdException.Create(RSThreadComponentLoopAlreadyRunning); // TODO: create a new Exception class for this
  end;
  FLoop := AValue;
end;

procedure TIdThreadComponent.SetThreadName(const AValue: string);
begin
  if IsRunning then begin
    raise EIdException.Create(RSThreadComponentThreadNameAlreadyRunning); // TODO: create a new Exception class for this
  end;
  FThreadName := AValue;
end;

function TIdThreadComponent.IsRunning: Boolean;
begin
  if Assigned(FThread) then begin
    Result := not FThread.Stopped;
  end else begin
    Result := False;
  end;
end;

procedure TIdThreadComponent.InitComponent;
begin
  inherited InitComponent;
  StopMode := IdThreadComponentDefaultStopMode;
  Priority := IdThreadComponentDefaultPriority;
end;

end.