Function Rpad_u(str1 In Varchar2 
              , len In Pls_Integer
              , pad In Varchar2 
              )
  Return Varchar2          
Is

  istr_len Pls_integer;
  ipad_len Pls_integer;
  irep_tm  Pls_integer;

  ----------------   
  Function Replicate( px in Varchar2
                , pn In Pls_integer -- целая степень
                ) return Varchar2 
  Is

    degree Pls_integer;
    x_lc Long;
    mresult Long;
  Begin
    If pn = 0 Then return ''; End If;
    degree := pn; 
    x_lc := px;

    While BITAND(degree,1) = 0 
    Loop
      degree := Floor(0.5*degree);
      x_lc := x_lc||x_lc;
    End Loop; 
    mresult := x_lc;

    degree := Floor(0.5*degree);
    
    While degree != 0
    Loop
      x_lc := x_lc||x_lc;

      If BITAND(degree,1) != 0
        Then
          mresult := mresult||x_lc;
      End If;
      degree := Floor(0.5*degree);
    End Loop;
    Return mresult; 
  End;   
  ------------------------  
Begin 
  If len > 0 
    Then
    istr_len := length(str1);
    ipad_len := length(pad);
    irep_tm := ceil((len - istr_len) / ipad_len);
    
    Return Case When irep_tm > 0
                Then
                  substr(concat(str1, replicate(pad, irep_tm)), 1, len)
                When ipad_len > 0
                  Then   
                   substr(str1, 1, len)
                Else 
                  Null  
                End;  
  End If;    
  Return Null;
End;