dxsock.pas

Well known and usefull component for delphi 7

      //    else begin
      //       DXString.DoSleepEx(1);
      //       DXString.ProcessWindowsMessageQueue;
      //    end;
      // End;
      // </CODE>
      // 
      // Note
      // It is crucial to test this property during any form of a
      // loop. A common mistake is to assume this property will return
      // the status of the connection when you have not tried to
      // receive data from the socket layer. To achieve that
      // functionality your loop must occasionally test the readable
      // property and the characters to read property.
      // 
      // See Also
      // Readable, CharactersToRead, ReceiveLength, ValidSocket, LastCommandStatus,
      // WaitForData, DroppedConnection                                                         
      // =======================================================================================
property Connected:Boolean read IsConnected;
      // ============================================================
      // This property provides a mechanism for asking the socket
      // layer for the total number of bytes existing in its internal
      // buffer. When used in conjunction with the readable property
      // you are able to detect hot disconnects. As the readable
      // property will return a value of true meaning that theres
      // something available to be read however the CharactersToRead
      // property will return 0.                                     
      // ============================================================
property CharactersToRead:Integer read CountWaiting;
      // ============================================================
      // This property is provided to make your transition from using
      // the Borland socket implementation to DXSock much easier. It
      // functions exactly like the CharactersToRead property.
      // 
      // Summary
      // CharactersToRead, Readable, Connected                       
      // ============================================================
property ReceiveLength:Integer read CountWaiting;
// =============================================================
// This property is used to test if the socket handle is still
// valid. A socket handle is normally invalid if you have not
// established a connection, tried to force accepting a
// connection when there was no connection waiting, or have
// already closed the socket.<B>
// 
// </B>
//
// Note
// You will normally use this routine in the case where you plan
// to reuse an existing socket for another connection.
// 
// See Also
// Connected, Readable, LastCommandStatus                       
// =============================================================
property ValidSocket:Boolean read IsValidSocket;
      // =============================================================
      // This property is used to test if the last read routine failed
      // due to the lack of data present at the socket layer.
      // 
      // See Also
      // LastCommandStatus, Connected, ValidSocket                    
      // =============================================================
property LastReadTimeout:Boolean read fReadTimeout;
      // =======================================================
      // This property is used to inquire the status of the last
      // socket layer command.
      // 
      // 
      // 
      // 
      // 
      // See Also
      // GetErrorStr, GetErrorDesc, LastReadTimeout             
      // =======================================================
property LastCommandStatus:Integer read FErrStatus write FErrStatus;
      // =============================================================
      // Internally all output routines use a chunking technique, this
      // property allows you to specify how much data per output call
      // to send to the actual socket layer buffer.
      // 
      // 
      //
      // bsfRealSmall=128
      // 
      // bsfSmall=256
      // 
      // bsfNormal=512
      // 
      // bsfBigger2048
      // 
      // bsfBiggest=4096
      // 
      // else use the gloabl constant TDXHugeSize
      // 
      // See Also
      // TooManyCharacters                                            
      // =============================================================
property OutputBufferSize:TDXBlockSizeFlags read fBlockSizeFlags
         write SetfBlockSizeFlags;
      // =========================================================
      // This property is used to assess the threshold to avoid
      // hacker-overrun attacks. Default is 2048 bytes, which is
      // usually more than enough for any protocol implementation.
      // This property is used by all routines that read from the
      // socket layer checking for a specified delimiter.
      // 
      // See Also
      // ReadLn, OutputBufferSize                                 
      // =========================================================
property TooManyCharacters:Integer read fTooManyCharacters
         write fTooManyCharacters;
      // =======================================================
      // This property provides a mechanism to query the current
      // instance of TDXSock if the instance is using UDP.<B>
      // 
      // </B>
      //
      // Note
      // Provided for internal usage for the different threading
      // models, but documented since the property is public.   
      // =======================================================
property IsUDPMode:Boolean read fbIsUDP
         write fbIsUDP;
      // =========================================================
      // This property provides a mechanism to query the current
      // instance of TDXSock if the instance is using socket layer
      // Keep-Alive packets. (enabled by default in DXSock)       
      // =========================================================
property IsKeepAliveMode:Boolean read fbIsKeepAlive write fbIsKeepAlive;
      // =========================================================
      // This property provides a mechanism that returns the IP
      // address of the client that is currently connected to this
      // instance of TDXSock.
      // 
      // See Also
      // PeerPort, LocalIPAddress                                 
      // =========================================================
property PeerIPAddress:string read GlobalPeerIPAddress
         write GlobalPeerIPAddress;
      // ===========================================================
      // This property provides a mechanism that returns the port of
      // the client that is currently connected to this instance of
      // TDXSock.
      // 
      // See Also
      // PeerIPAddress, LocalPort                                   
      // ===========================================================
property PeerPort:Integer read GlobalPeerPort
         write GlobalPeerPort;
      // ======================================================
      // This property provides a mechanism that returns the IP
      // address the client is currently connected to for this
      // instance of TDXSock.
      // 
      // See Also
      // LocalPort, BindTo, PeerIPAddress                      
      // ======================================================
property LocalIPAddress:string read GetLocalIPAddr;
      // ============================================================
      // This property provides a mechanism that returns the port the
      // client is currently connected to for this instance of
      // TDXSock.
      // 
      // See Also
      // LocalIPAddress, PeerPort                                    
      // ============================================================
property LocalPort:Integer read GetLocalPort;
      // ============================================================
      // This property is used to inquire if the socket layer has
      // something available to be checked for. It can be a pending
      // disconnect notification, or an unread packets.
      // 
      // Note
      // A common mistake is to test this property very often in a
      // loop. You should only use this in conjunction with the
      // CharactersToRead property to detect a hot disconnect. As the
      // readable property will return a value of true meaning that
      // theres something available to be read however the
      // CharactersToRead property will return 0.
      // 
      // See Also
      // Connected, Writable                                         
      // ============================================================
property Readable:Boolean read IsReadable;
      // =======================================================
      // This property is used to inquire if the socket layer is
      // capable of sending data.
      // 
      // 
      // 
      // Note
      // We have never really found a use for this function.
      // 
      // See Also
      // Readable                                               
      // =======================================================
property Writable:Boolean read IsWritable;
      // =============================================================
      // This property provides a mechanism that will inform you of
      // the release date of the source code being used for your
      // server. You can use this internally for your development team
      // for when reporting problems to the support staff.            
      // =============================================================
property ReleaseDate:string read GetReleaseDate
         write SetReleaseDate;
      // =============================================================
      // This property provides a mechanism for on-the-fly compression
      // \or basic encryption. When this event is implemented in your
      // server, it will be automatically fired before every socket
      // layer write - allowing you to modify the inbound data and
      // return it as outbound data. It then is automatically fired
      // after the write has occurred so you can destroy the temporary
      // pointer used for the outbound data. If you have implemented
      // this functionality for your server, youll need to manually
      // call the FilterRead function after every read. The reason it
      // cannot automatically call the FilterRead routine is due to
      // the fact some of the read routines in the suite accept
      // pointers as parameters - thus it would create a memory leak. 
      // =============================================================
property OnFilter:TDXFilterCallBack read feOnFilter
         write feOnFilter;
{$IFDEF TLS_EDITION}
      property OnReadFilter:TDXFilterCallBack read feOnReadFilter
         write feOnReadFilter;
{$ENDIF}
      property OnWriteBuffer : TDXWriteBufferCallback read feOnWriteBuffer write feOnWriteBuffer;
      property OnReadBuffer  : TDXReadBufferCallback  read feOnReadBuffer  write feOnReadBuffer;
   end;

implementation

uses
{$IFNDEF LINUX}
   Windows,
{$ENDIF}
   SysUtils;

function TDXSock.GetReleaseDate:string;
begin
   Result:=BPDX_RELEASE_DATE;
end;

procedure TDXSock.SetReleaseDate (value:string) ;
begin
  // Absorb!
end;

constructor TDXSock.Create (AOwner:TComponent) ;
begin
   inherited Create (AOwner) ;// RC2
   FReadTimeout:=False;
   System.GetMem(FPeekBuffer,PeekBufferSize);
   LastFBlockSizeFlags:=bsfZero;
   SetFBlockSizeFlags (bsfHuge) ;
   if not SocketLayerLoaded then
      ShowMessageWindow ('Fatal Socket Error','(WSAStartup) '+GetErrorStr) ;
   fTooManyCharacters:=2048;
   Sock:=INVALID_SOCKET;
   fbIsUDP:=False;
   fbIsKeepAlive:=False;
   fbClientMode:=False;
   FUseBlocking:=True;
   GlobalPeerPort:=0;
   GlobalPeerIPAddress:='';
   VarConstSizeofTSockAddrIn:=ConstSizeofTSockAddrIn;
end;