xref: /netbsd/lib/libcurses/erase.c (revision bf9ec67e)
1 /*	$NetBSD: erase.c,v 1.15 2000/05/20 15:12:15 mycroft Exp $	*/
2 
3 /*
4  * Copyright (c) 1981, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)erase.c	8.2 (Berkeley) 5/4/94";
40 #else
41 __RCSID("$NetBSD: erase.c,v 1.15 2000/05/20 15:12:15 mycroft Exp $");
42 #endif
43 #endif				/* not lint */
44 
45 #include "curses.h"
46 #include "curses_private.h"
47 
48 #ifndef _CURSES_USE_MACROS
49 
50 /*
51  * erase --
52  *	Erases everything on stdscr.
53  */
54 int
55 erase(void)
56 {
57 	return werase(stdscr);
58 }
59 
60 #endif
61 
62 /*
63  * werase --
64  *	Erases everything on the window.
65  */
66 int
67 werase(WINDOW *win)
68 {
69 
70 	int     minx, y;
71 	__LDATA *sp, *end, *start, *maxx;
72 
73 #ifdef DEBUG
74 	__CTRACE("werase: (%0.2o)\n", win);
75 #endif
76 #ifdef __GNUC__
77 	maxx = NULL;		/* XXX gcc -Wuninitialized */
78 #endif
79 	for (y = 0; y < win->maxy; y++) {
80 		minx = -1;
81 		start = win->lines[y]->line;
82 		end = &start[win->maxx];
83 		for (sp = start; sp < end; sp++)
84 			if (sp->ch != ' ' || sp->attr != 0 ||
85 			    sp->bch != win->bch || sp->battr != win->battr) {
86 				maxx = sp;
87 				if (minx == -1)
88 					minx = sp - start;
89 				sp->ch = ' ';
90 				sp->bch = win->bch;
91 				sp->attr = 0;
92 				sp->battr = win->battr;
93 			}
94 		if (minx != -1)
95 			__touchline(win, y, minx, maxx - win->lines[y]->line);
96 	}
97 	wmove(win, 0, 0);
98 	return (OK);
99 }
100