/*
 * Copyright 1988 by the Massachusetts Institute of Technology.
 *
 * For copying and distribution information, please see
 * the file <mit-cpyright.h>.
 *
 * This routine generates an odd-parity table for use in key generation.
 */

#include <afsconfig.h>
#include <afs/param.h>

RCSID
    ("$Header: /cvs/openafs/src/des/make_odd.c,v 1.4 2003/07/15 23:15:00 shadow Exp $");

#include <mit-cpyright.h>
#include <stdio.h>

void
gen(stream)
     FILE *stream;
{
    /*
     * map a byte into its equivalent with odd parity, where odd
     * parity is in the least significant bit
     */
    register int i, j, k, odd;

    fprintf(stream, "static unsigned char const odd_parity[256] = {\n");

    for (i = 0; i < 256; i++) {
	odd = 0;
	/* shift out the lsb parity bit */
	k = i >> 1;
	/* then count the other bits */
	for (j = 0; j < 7; j++) {
	    odd ^= (k & 1);
	    k = k >> 1;
	}
	k = i & ~1;
	if (!odd)
	    k |= 1;
	fprintf(stream, "%3d", k);
	if (i < 255)
	    fprintf(stream, ", ");
	if (i % 8 == 0)
	    fprintf(stream, "\n");
    }
    fprintf(stream, "};\n");
}
