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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static char sccsid[] = "@(#)erase.c	8.2 (Berkeley) 5/4/94";
32 #endif	/* not lint */
33 
34 #include "curses.h"
35 
36 /*
37  * werase --
38  *	Erases everything on the window.
39  */
40 int
werase(win)41 werase(win)
42 	register WINDOW *win;
43 {
44 
45 	register int minx, y;
46 	register __LDATA *sp, *end, *start, *maxx;
47 
48 #ifdef DEBUG
49 	__CTRACE("werase: (%0.2o)\n", win);
50 #endif
51 	for (y = 0; y < win->maxy; y++) {
52 		minx = -1;
53 		start = win->lines[y]->line;
54 		end = &start[win->maxx];
55 		for (sp = start; sp < end; sp++)
56 			if (sp->ch != ' ' || sp->attr != 0) {
57 				maxx = sp;
58 				if (minx == -1)
59 					minx = sp - start;
60 				sp->ch = ' ';
61 				sp->attr = 0;
62 			}
63 		if (minx != -1)
64 			__touchline(win, y, minx, maxx - win->lines[y]->line,
65 			   0);
66 	}
67 	return (OK);
68 }
69