xref: /illumos-gate/usr/src/lib/libcurses/screen/overlap.c (revision 42b53e0fbc5c05289c3d334bb864b784fafe5ce4)
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 /*LINTLIBRARY*/
41 
42 #include	<sys/types.h>
43 #include	"curses_inc.h"
44 
45 /*
46  * This routine writes Srcwin on Dstwin.
47  * Only the overlapping region is copied.
48  */
49 
50 int
51 _overlap(WINDOW *Srcwin, WINDOW *Dstwin, int Overlay)
52 {
53 	int	sby, sbx, sey, sex, dby, dbx, dey, dex,
54 		top, bottom, left, right;
55 
56 #ifdef	DEBUG
57 	if (outf)
58 		fprintf(outf, "OVERWRITE(0%o, 0%o);\n", Srcwin, Dstwin);
59 #endif	/* DEBUG */
60 
61 	sby = Srcwin->_begy;	dby = Dstwin->_begy;
62 	sbx = Srcwin->_begx;	dbx = Dstwin->_begx;
63 	sey = sby + Srcwin->_maxy;	dey = dby + Dstwin->_maxy;
64 	sex = sbx + Srcwin->_maxx;	dex = dbx + Dstwin->_maxx;
65 
66 	if (sey < dby || sby > dey || sex < dbx || sbx > dex)
67 		return (ERR);
68 
69 	top = _MAX(sby, dby);	bottom = _MIN(sey, dey);
70 	left = _MAX(sbx, dbx);	right = _MIN(sex, dex);
71 
72 	sby = top - sby;		sbx = left - sbx;
73 	dey = bottom - dby - 1;	dex = right - dbx - 1;
74 	dby = top - dby;		dbx = left - dbx;
75 
76 	return (copywin(Srcwin, Dstwin, sby, sbx, dby, dbx, dey, dex, Overlay));
77 }
78