Packet.cpp

/*
** libutil++
** $Id: Packet.cpp 1653 2016-02-28 19:54:59Z sella $
** Copyright (c) 2011-2016 Digital Genesis, LLC. All Rights Reserved.
** Released under the LGPL Version 2.1 License.
** http://www.digitalgenesis.com
*/

static const char rcsid[] __attribute__((used)) = "$Id: Packet.cpp 1653 2016-02-28 19:54:59Z sella $";

#include "Packet.h"

using namespace sella::util;

uint8_t Packet::csum(uint8_t *buf, int bytes) throw () {
        uint16_t *buf16 = (uint16_t*) buf;
        uint32_t sum;

        for (sum = 0; bytes > 0; bytes -= 2) {
                sum += *buf16++;
        }

        sum = (sum >> 16) + (sum & 0xffff);
        sum += (sum >> 16);

        return ~sum;
}

uint16_t Packet::csum(uint16_t *buf, int words) throw () {
        uint32_t sum;

        for (sum = 0; words > 0; words--) {
                sum += *buf++;
        }

        sum = (sum >> 16) + (sum & 0xffff);
        sum += (sum >> 16);

        return ~sum;
}

/*
** vim: noet ts=3 sw=3
*/