usr/src/usr.bin/window/wwdelline.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are permitted
 * provided that the above copyright notice and this paragraph are
 * duplicated in all such forms and that any documentation,
 * advertising materials, and other materials related to such
 * distribution and use acknowledge that the software was developed
 * by the University of California, Berkeley.  The name of the
 * University may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char sccsid[] = "@(#)wwdelline.c 3.10 (Berkeley) %G%";
#endif /* not lint */

#include "ww.h"

wwdelline(w, row)
register struct ww *w;
int row;
{
        register i;
        register union ww_char **cpp, **cqq;
        register union ww_char *cp;
        int row1, row2;
        char deleted;
        int visible;

        /*
         * Scroll first.
         */
        if ((row1 = row) < w->ww_i.t) {
                row1 = w->ww_i.t;
        }
        if ((row2 = w->ww_b.b) > w->ww_i.b) {
                row2 = w->ww_i.b;
                visible = 0;
        } else
                visible = 1;
        deleted = wwscroll1(w, row1, row2, 1, visible);

        /*
         * Fix the buffer.
         * But leave clearing the last line for wwclreol().
         */
        cpp = &w->ww_buf[row];
        cqq = cpp + 1;
        cp = *cpp;
        for (i = w->ww_b.b - row; --i > 0;)
                *cpp++ = *cqq++;
        *cpp = cp;

        /*
         * Now clear the last line.
         */
        if (visible)
                wwclreol1(w, w->ww_b.b - 1, w->ww_b.l, deleted);
        else {
                cp += w->ww_b.l;
                for (i = w->ww_b.nc; --i >= 0;)
                        cp++->c_w = ' ';
        }
}