nel/src/misc/cdb_check_sum.cpp

   1 // Ryzom - MMORPG Framework <http://dev.ryzom.com/projects/ryzom/>
   2 // Copyright (C) 2010  Winch Gate Property Limited
   3 //
   4 // This source file has been modified by the following contributors:
   5 // Copyright (C) 2013  Laszlo KIS-ADAM (dfighter) <dfighter1985@gmail.com>
   6 //
   7 // This program is free software: you can redistribute it and/or modify
   8 // it under the terms of the GNU Affero General Public License as
   9 // published by the Free Software Foundation, either version 3 of the
  10 // License, or (at your option) any later version.
  11 //
  12 // This program is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU Affero General Public License for more details.
  16 //
  17 // You should have received a copy of the GNU Affero General Public License
  18 // along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20 #include "stdmisc.h"
  21 #include "nel/misc/cdb_check_sum.h"
  22
  23 #ifdef DEBUG_NEW
  24 #define new DEBUG_NEW
  25 #endif
  26
  27 namespace NLMISC{
  28
  29 /*
  30  * Constructor
  31  */
  32
  33 CCDBCheckSum::CCDBCheckSum()
  34 {
  35         //arbitrary values
  36         _Sum = 0;
  37         _Factor = 55665;
  38         _Const1 = 52845;
  39         _Const2 = 22719;
  40 };
  41
  42 ///add an uint8 to the sum
  43 void CCDBCheckSum::add(uint8 el)
  44 {
  45         uint32 cipher = (el ^ (_Factor >> 8));
  46         _Factor = (cipher + _Factor) * _Const1 + _Const2;
  47         _Sum += cipher;
  48 }
  49
  50 }
  51