xref: /illumos-gate/usr/src/lib/libcurses/screen/wredrawln.c (revision 4eaa471005973e11a6110b69fe990530b3b95a38)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1997 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 /*LINTLIBRARY*/
43 
44 /*
45  * This routine indicates to curses that a screen line is garbaged and
46  * should be thrown away before having anything written over the top of it.
47  * It could be used for programs such as editors which want a command to
48  * redraw just a single line. Such a command could be used in cases where
49  * there is a noisy line and redrawing the entire screen would be subject
50  * to even more noise. Just redrawing the single line gives some semblance
51  * of hope that it would show up unblemished.
52  *
53  * This is a more refined version of clearok
54  */
55 
56 #include	<sys/types.h>
57 #include	"curses_inc.h"
58 
59 int
60 wredrawln(WINDOW *win, int begline, int numlines)
61 {
62 	short	*firstch, *efirstch;
63 
64 	if (numlines <= 0)
65 		return (ERR);
66 	if (begline < 0)
67 		begline = 0;
68 	if (begline + numlines > win->_maxy)
69 		numlines = win->_maxy - begline;
70 
71 	firstch = win->_firstch + begline;
72 	efirstch = firstch + numlines;
73 	while (firstch < efirstch)
74 		*firstch++ = _REDRAW;
75 
76 	return (win->_immed ? wrefresh(win) : OK);
77 }
78