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 (c) 1995, by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * wscrl.c
31  *
32  * XCurses Library
33  *
34  * Copyright 1990, 1995 by Mortice Kern Systems Inc.  All rights reserved.
35  *
36  */
37 
38 #ifdef M_RCSID
39 #ifndef lint
40 static char rcsID[] = "$Header: /rd/src/libc/xcurses/rcs/wscrl.c 1.4 1995/07/26 17:43:20 ant Exp $";
41 #endif
42 #endif
43 
44 #include <private.h>
45 #include <string.h>
46 
47 /*f
48  * For positive n scroll the window up n lines (line i+n becomes i);
49  * otherwise scroll the window down n lines.
50  */
51 int
wscrl(w,n)52 wscrl(w, n)
53 WINDOW *w;
54 int n;
55 {
56 	int y, x, width, start, finish, to;
57 
58 #ifdef M_CURSES_TRACE
59 	__m_trace("wscrl(%p, %d)", w, n);
60 #endif
61 
62 	if (n == 0)
63 		return __m_return_code("wscrl", OK);
64 
65 	/* Shuffle pointers in order to scroll.  The region
66 	 * from start to finish inclusive will be moved to
67 	 * either the top or bottom of _line[].
68 	 */
69 	if (0 < n) {
70 		start = w->_top;
71 		finish = w->_top + n - 1;
72 		to = w->_bottom;
73 	} else {
74 		start = w->_bottom + n;
75 		finish = w->_bottom - 1;
76 		to = w->_top;
77 	}
78 
79 	/* Blank out new lines. */
80 	if (__m_cc_erase(w, start, 0, finish, w->_maxx-1) == -1)
81 		return __m_return_code("wscrl", ERR);
82 
83 	/* Scroll lines by shuffling pointers. */
84 	(void) __m_ptr_move((void **) w->_line, w->_maxy, start, finish, to);
85 
86 	if ((w->_flags & W_FULL_WINDOW)
87 	&& w->_top == 0 && w->_bottom == w->_maxy)
88 		w->_scroll += n;
89 	else
90 		w->_scroll = 0;
91 
92 	(void) wtouchln(w, 0, w->_maxy, 1);
93 
94 	WSYNC(w);
95 
96 	return __m_return_code("wscrl", WFLUSH(w));
97 }
98