xref: /netbsd-src/lib/libcurses/erase.c (revision 38023541164cff097d5fadec63134189b1453b8c)
1 /*
2  * Copyright (c) 1981, 1993
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
35 /* from: static char sccsid[] = "@(#)erase.c	8.1 (Berkeley) 6/4/93"; */
36 static char *rcsid = "$Id: erase.c,v 1.6 1993/11/09 04:07:29 cgd Exp $";
37 #endif	/* not lint */
38 
39 #include <curses.h>
40 
41 /*
42  * werase --
43  *	Erases everything on the window.
44  */
45 int
46 werase(win)
47 	register WINDOW *win;
48 {
49 
50 	register int minx, y;
51 	register __LDATA *sp, *end, *start, *maxx;
52 
53 #ifdef DEBUG
54 	__CTRACE("werase: (%0.2o)\n", win);
55 #endif
56 	for (y = 0; y < win->maxy; y++) {
57 		minx = -1;
58 		start = win->lines[y]->line;
59 		end = &start[win->maxx];
60 		for (sp = start; sp < end; sp++)
61 			if (sp->ch != ' ' || sp->attr != 0) {
62 				maxx = sp;
63 				if (minx == -1)
64 					minx = sp - start;
65 				sp->ch = ' ';
66 				sp->attr = 0;
67 			}
68 		if (minx != -1)
69 			__touchline(win, y, minx, maxx - win->lines[y]->line,
70 			   0);
71 	}
72 	return (OK);
73 }
74