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/*
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* Copyright (C) 2000,2001 Onlyer (onlyer@263.net)
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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*/
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#include "common/setup_before.h"
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#include "common/setup_after.h"
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extern int d2charsave_checksum(unsigned char const * data, unsigned int len,unsigned int offset)
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{
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int checksum;
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unsigned int i;
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unsigned int ch;
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if (!data) return 0;
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checksum=0;
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for (i=0; i<len; i++) {
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if (i>=offset && i<offset+sizeof(int)) ch=0;
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else ch = *data;
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ch+=(checksum<0);
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checksum=2*checksum+ch;
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data++;
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}
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return checksum;
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}
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