usr/src/lib/libcurses/erase.c

/*
 * Copyright (c) 1981, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)erase.c     8.1 (Berkeley) 6/4/93";
#endif  /* not lint */

#include <curses.h>

/*
 * werase --
 *      Erases everything on the window.
 */
int
werase(win)
        register WINDOW *win;
{

        register int minx, y;
        register __LDATA *sp, *end, *start, *maxx;

#ifdef DEBUG
        __CTRACE("werase: (%0.2o)\n", win);
#endif
        for (y = 0; y < win->maxy; y++) {
                minx = -1;
                start = win->lines[y]->line;
                end = &start[win->maxx];
                for (sp = start; sp < end; sp++)
                        if (sp->ch != ' ' || sp->attr != 0) {
                                maxx = sp;
                                if (minx == -1)
                                        minx = sp - start;
                                sp->ch = ' ';
                                sp->attr = 0;
                        }
                if (minx != -1)
                        __touchline(win, y, minx, maxx - win->lines[y]->line,
                           0);
        }
        return (OK);
}