/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/*        All Rights Reserved   */

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved. The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

/*
 * SORTS UP.
 * IF THERE ARE NO EXCHANGES (IEX=0) ON A SWEEP
 * THE COMPARISON GAP (IGAP) IS HALVED FOR THE NEXT SWEEP
 */
void
shell(int n, int (*comp)(), int (*exch)())
{
        int igap, iplusg, iex, i, imax;
        igap = n;
        while (igap > 1) {
                igap /= 2;
                imax = n-igap;
                do {
                        iex = 0;
                        for (i = 0; i < imax; i++) {
                                iplusg = i + igap;
                                if ((*comp)(i, iplusg)) continue;
                                (*exch) (i, iplusg);
                                iex = 1;
                        }
                }
                while (iex > 0)
                        ;
        }
}