//============================================================
//         T  C  P  _  S  T  R  E  A  M
//------------------------------------------------------------
//
//  maintain a iostream.
// 
//     include lossless compression
//------------------------------------------------------------
//
//
//-------------- I M P O R T A N T ------------------------
//  1) POSSIBILITY for improvment? 
//        reserve a large buffer size   
//  2) break the input/output stream into small pieces.
//---------------------------------------------------------


class tcp_Stream
{
   public:
            tcp_Stream ()         {
                                   stream_fd = 0; 
                                   COMPRESSION_TYPE = COMPRESS_NON;
                                   total_byte_read =0;
                                   total_byte_write=0;
                                   total_pixel_write=0;
                                   total_compressed_coeff_write =0;
                                  }
            tcp_Stream ( int fd ) {
                                   stream_fd = fd;
                                   COMPRESSION_TYPE = COMPRESS_NON;
                                   total_byte_read =0;
                                   total_byte_write=0;
                                   total_pixel_write=0;
                                   total_compressed_coeff_write =0;
                                  }
           ~tcp_Stream ()         {cout << "delete stream "
                                        << stream_fd << endl; }

      int   write_byte   ( unsigned char * buffer, unsigned long nos_byte );
      int   write_int    (          int                          );
      int   write_integers(         int  * buffer, long nos_int  );
      int   write_string (          char * );

      int   read_int     (          int  *);
      int   read_string  (          char *,  int );
      int   read_integers(          int  * buffer, long nos_int_to_be_read  );
      int   read_byte    ( unsigned char * buffer, unsigned long nos_byte );
                          
                              // ::close refers to the original close ()
                              // the statement is redudent.
                              // the stream should be close in the 
                              // main program which open it.
//    int      close        ()  {return ::close (stream_fd);}

      int      stream_fd;
      unsigned long total_byte_read;
      unsigned long total_byte_write;
      unsigned long total_pixel_write;
      unsigned long total_compressed_coeff_write;

      int   COMPRESSION_TYPE;


static const int   COMPRESS_NON = 0;
static const int   COMPRESS_LZW = 1;
static const int   COMPRESS_GZ  = 2;
};