Inc(I);
        J := I;
        while (J <= Length(Params)) and (Params[J] in ['A'..'Z', 'a'..'z', '0'..'9']) do
            Inc(J);
        KeyWord := UpperCase(Copy(Params, I, J - I));

        { Extract parameters, ignoring leading spaces and tabs }
        while (J <= Length(Params)) and (Params[J] in [' ', #9]) do
            Inc(J);
        Params := Copy(Params, J, Length(Params));

        { Pass the command to the component user to let him a chance to }
        { handle it. If it does, he must return the answer.             }
        TriggerClientCommand(Client, Keyword, Params, Answer);
        if Answer <> '' then begin
            { Event handler has processed the client command, send the answer }
            SendAnswer(Client, Answer);
            Exit;
        end;

        { The command has not been processed, we'll process it }
        if Keyword = '' then begin
            { Empty keyword (should never occurs) }
            SendAnswer(Client, Format(msgCmdUnknown, [Params]));
            Exit;
        end;

        { We need to process the client command, search our command table }
        I := 0;
        while I <= High(FCmdTable) do begin
            if FCmdTable[I].KeyWord = KeyWord then begin
                FCmdTable[I].Proc(Client, KeyWord, Params, Answer);
                SendAnswer(Client, Answer);
                Exit;
            end;
            Inc(I);
        end;
        SendAnswer(Client, Format(msgCmdUnknown, [KeyWord]));
    except
        on E:Exception do begin
            SendAnswer(Client, '501 ' + E.Message);
        end;
    end;
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.ClientDataSent(Sender : TObject; Error : Word);
var
    Client  : TFtpCtrlSocket;
begin
    Client := Sender as TFtpCtrlSocket;
    if Client.CloseRequest then begin
        Client.CloseRequest := FALSE;
        PostMessage(FWindowHandle, WM_FTPSRV_CLOSE_REQUEST, 0, LongInt(Client));
    end;
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.ClientSessionClosed(Sender : TObject; Error : Word);
begin
    PostMessage(FWindowHandle, WM_FTPSRV_CLIENT_CLOSED, 0, LongInt(Sender));
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.WMFtpSrvClientClosed(var msg: TMessage);
var
    Client : TFtpCtrlSocket;
begin
    Client := TFtpCtrlSocket(Msg.LParam);
    try
        FClientList.Remove(Client);
        TriggerClientDisconnect(Client, Error);
    finally
        Client.Destroy;
    end;
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.WMFtpSrvAbortTransfer(var msg: TMessage);
var
    Data : TWSocket;
begin
    Data := TWSocket(Msg.LParam);
    Data.ShutDown(2);
    Data.Close;
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.WMFtpSrvCloseData(var msg: TMessage);
var
    Data : TWSocket;
begin
    if msg.WParam > 0 then begin
{$IFNDEF VER80}
        Sleep(0);  { Release time slice }
{$ENDIF}
        PostMessage(FWindowHandle, Msg.Msg, msg.WParam - 1, msg.LParam);
    end
    else begin
        Data := TWSocket(Msg.LParam);
        Data.Close;
    end;
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
function TFtpServer.GetClientCount : Integer;
begin
    if Assigned(FClientList) then
        Result := FClientList.Count
    else
        Result := 0;
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerServerStart;
begin
    if Assigned(FOnStart) then
        FOnStart(Self);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerServerStop;
begin
    if Assigned(FOnStop) then
        FOnStop(Self);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerAuthenticate(
    Client            : TFtpCtrlSocket;
    UserName          : String;
    PassWord          : String;
    var Authenticated : Boolean);
begin
    if Assigned(FOnAuthenticate) then
        FOnAuthenticate(Self, Client, UserName, Password, Authenticated);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerChangeDirectory(
    Client         : TFtpCtrlSocket;
    Directory      : String;
    var Allowed    : Boolean);
begin
    if Assigned(FOnChangeDirectory) then
        FOnChangeDirectory(Self, Client, Directory, Allowed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerMakeDirectory(
    Client         : TFtpCtrlSocket;
    Directory      : String;
    var Allowed    : Boolean);
begin
    if Assigned(FOnMakeDirectory) then
        FOnMakeDirectory(Self, Client, Directory, Allowed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerBuildDirectory(
    Client        : TFtpCtrlSocket;
    var Params    : TFtpString;
    Detailed      : Boolean);
begin
    if Assigned(FOnBuildDirectory) then
        FOnBuildDirectory(Self, Client, Params, Detailed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerAlterDirectory(
    Client        : TFtpCtrlSocket;
    var Params    : TFtpString;
    Detailed      : Boolean);
begin
    if Assigned(FOnAlterDirectory) then
        FOnAlterDirectory(Self, Client, Params, Detailed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerSendAnswer(
    Client     : TFtpCtrlSocket;
    var Answer : TFtpString);
begin
    if Assigned(FOnAnswerToClient) then
        FOnAnswerToClient(Self, Client, Answer);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerClientDisconnect(Client : TFtpCtrlSocket; Error : Word);
begin
    if Assigned(FOnClientDisconnect) then
        FOnClientDisconnect(Self, Client, Error);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerClientConnect(Client : TFtpCtrlSocket; Error : Word);
begin
    if Assigned(FOnClientConnect) then
        FOnClientConnect(Self, Client, Error);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerStorSessionConnected(
    Client : TFtpCtrlSocket; Data : TWSocket; Error : Word);
begin
    if Assigned(FOnStorSessionConnected) then
        FOnStorSessionConnected(Self, Client, Data, Error);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerRetrSessionConnected(
    Client : TFtpCtrlSocket; Data : TWSocket; Error : Word);
begin
    if Assigned(FOnRetrSessionConnected) then
        FOnRetrSessionConnected(Self, Client, Data, Error);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerStorSessionClosed(
    Client : TFtpCtrlSocket; Data : TWSocket; Error : Word);
begin
    if Assigned(FOnStorSessionClosed) then
        FOnStorSessionClosed(Self, Client, Data, Error);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerRetrSessionClosed(
    Client : TFtpCtrlSocket; Data : TWSocket; Error : Word);
begin
    if Assigned(FOnRetrSessionClosed) then
        FOnRetrSessionClosed(Self, Client, Data, Error);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerClientCommand(
    Client      : TFtpCtrlSocket;
    var Keyword : TFtpString;
    var Params  : TFtpString;
    var Answer  : TFtpString);
begin
    if Assigned(FOnClientCommand) then
        FOnClientCommand(Self, Client, KeyWord, Params, Answer);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerValidatePut(
    Client        : TFtpCtrlSocket;
    var FilePath  : TFtpString;
    var Allowed   : Boolean);
begin
    if Assigned(FOnValidatePut) then
        FOnValidatePut(Self, Client, FilePath, Allowed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerValidateDele(
    Client        : TFtpCtrlSocket;
    var FilePath  : TFtpString;
    var Allowed   : Boolean);
begin
    if Assigned(FOnValidateDele) then
        FOnValidateDele(Self, Client, FilePath, Allowed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerValidateRnFr(
    Client        : TFtpCtrlSocket;
    var FilePath  : TFtpString;
    var Allowed   : Boolean);
begin
    if Assigned(FOnValidateRnFr) then
        FOnValidateRnFr(Self, Client, FilePath, Allowed);
end;


{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TFtpServer.TriggerValidateRnTo(
    Client        : TFtpCtrlSocket;
    var FilePath  : TFtpString;
    var Allowed   : Boolean);
begin
    if Assigned(FOnValidateRnTo) then
        FOnValidateRnTo(Self, Client, FilePath, Allowed);
end;