读一读Scktsrvr.exe的源程序

使用DELPHI做多层开发的朋友们都应该对Scktsrvr.exe这个程序不陌生的，
Borland公司在DELPHI中给出了它的源代码。
这是一个900来行的程序，程序不算长，
现在我只选其中部分仔细读一读。
走的线路大致是，从服务器接到客户端连接，处理客户端的一个请求（这儿
选了客户端向服务器发出的'取应用服务器列表'请求)

服务器接受了客户端连接后,
因为ServerSocket采用的是阻塞模式,服务器执行了下面这个线程来
服务客户端：

//SCKTMAIN.PAS

procedure TSocketDispatcherThread.ClientExecute;
var
  Data: IDataBlock;
  msg: TMsg;
  Obj: ISendDataBlock;
  Event: THandle;
  WaitTime: DWord;
begin
  CoInitialize(nil);                 //初始化COM
  try
    Synchronize(AddClient);             //在程序界面上显示客户信息,
        //用同步保证AddClient线程安全性
    FTransport := CreateServerTransport;
    try
      Event := FTransport.GetWaitEvent;
      PeekMessage(msg, 0, WM_USER, WM_USER, PM_NOREMOVE);
      GetInterface(ISendDataBlock, Obj);
      if FRegisteredOnly then
        FInterpreter := TDataBlockInterpreter.Create(Obj, SSockets) else
        FInterpreter := TDataBlockInterpreter.Create(Obj, ');
      try
        Obj := nil;
        if FTimeout = 0 then
          WaitTime := INFINITE else
          WaitTime := 60000;
        while not Terminated and FTransport.Connected do
        try
          case MsgWaitForMultipleObjects(1, Event, False, WaitTime, QS_ALLEVENTS) of
              //MsgWaitForMultipleObjects保持线程同步之用,
              //本文暂不细说它.
            WAIT_OBJECT_0:  //有数据来了
            begin
              WSAResetEvent(Event);
              Data := FTransport.Receive(False, 0);  //从客户端接收数据块
              if Assigned(Data) then
              begin
                FLastActivity := Now;
                FInterpreter.InterpretData(Data);//下面接着分析这儿
                Data := nil;
                FLastActivity := Now;
              end;
            end;
            WAIT_OBJECT_0 + 1:
              while PeekMessage(msg, 0, 0, 0, PM_REMOVE) do
                DispatchMessage(msg);
            WAIT_TIMEOUT:
              if (FTimeout > 0) and ((Now - FLastActivity) > FTimeout) then
                FTransport.Connected := False;
          end;
        except
          FTransport.Connected := False;
        end;
      finally
        FInterpreter.Free;
        FInterpreter := nil;
      end;
    finally
      FTransport := nil;
    end;

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