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#include	<sys/types.h>
45#include	"curses_inc.h"
46
47/*
48 *	Make a  derived window of an existing window. The two windows
49 *	share the same character image.
50 *		orig:	the original window
51 *		nl, nc:	numbers of lines and columns
52 *		by, bx:	coordinates for upper-left corner of the derived
53 *			window in the coord system of the parent window.
54 */
55
56WINDOW	*
57derwin(WINDOW *orig, int num_lines, int nc, int by, int bx)
58{
59	int	y;
60	WINDOW	*win = (WINDOW *) NULL, *par;
61	chtype	**w_y, **o_y;
62#ifdef	_VR3_COMPAT_CODE
63	_ochtype	**w_y16, **o_y16;
64#endif	/* _VR3_COMPAT_CODE */
65
66	/* make sure window fits inside the original one */
67	if (by < 0 || (by + num_lines) > orig->_maxy || bx < 0 ||
68	    (bx + nc) > orig->_maxx)
69		goto done;
70	if (nc == 0)
71		nc = orig->_maxx - bx;
72	if (num_lines == 0)
73		num_lines = orig->_maxy - by;
74
75	/* Create the window skeleton */
76	if ((win = _makenew(num_lines, nc, by + orig->_begy,
77	    bx + orig->_begx)) == NULL)
78		goto done;
79
80	/* inheritance */
81	/*LINTED*/
82	win->_parx = (short) bx;
83	/*LINTED*/
84	win->_pary = (short) by;
85	win->_bkgd = orig->_bkgd;
86	win->_attrs = orig->_attrs;
87	w_y = win->_y;
88	o_y = orig->_y;
89
90#ifdef	_VR3_COMPAT_CODE
91	if (_y16update) {
92		int	hby = by;
93
94		w_y16 = win ->_y16;
95		o_y16 = orig->_y16;
96
97		for (y = 0; y < num_lines; y++, hby++)
98			w_y16[y] = o_y16[hby] + bx;
99	}
100#endif	/* _VR3_COMPAT_CODE */
101
102	for (y = 0; y < num_lines; y++, by++)
103		w_y[y] = o_y[by] + bx;
104
105	win->_yoffset = orig->_yoffset;
106
107	/* update descendant number of ancestors */
108	win->_parent = orig;
109	for (par = win->_parent; par != NULL; par = par->_parent)
110		par->_ndescs += 1;
111
112done:
113	return (win);
114}
115