erase.c revision 1.8 
1/*
2 * Copyright (c) 1981, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#ifndef lint
35static char sccsid[] = "@(#)erase.c	8.2 (Berkeley) 5/4/94";
36#endif	/* not lint */
37
38#include "curses.h"
39
40/*
41 * werase --
42 *	Erases everything on the window.
43 */
44int
45werase(win)
46	register WINDOW *win;
47{
48
49	register int minx, y;
50	register __LDATA *sp, *end, *start, *maxx;
51
52#ifdef DEBUG
53	__CTRACE("werase: (%0.2o)\n", win);
54#endif
55	for (y = 0; y < win->maxy; y++) {
56		minx = -1;
57		start = win->lines[y]->line;
58		end = &start[win->maxx];
59		for (sp = start; sp < end; sp++)
60			if (sp->ch != ' ' || sp->attr != 0) {
61				maxx = sp;
62				if (minx == -1)
63					minx = sp - start;
64				sp->ch = ' ';
65				sp->attr = 0;
66			}
67		if (minx != -1)
68			__touchline(win, y, minx, maxx - win->lines[y]->line,
69			   0);
70	}
71	wmove(win, 0, 0);
72	return (OK);
73}
74