1/*	$NetBSD: scroll.c,v 1.27 2021/09/06 07:03:50 rin 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. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#ifndef lint
34#if 0
35static char sccsid[] = "@(#)scroll.c	8.3 (Berkeley) 5/4/94";
36#else
37__RCSID("$NetBSD: scroll.c,v 1.27 2021/09/06 07:03:50 rin Exp $");
38#endif
39#endif				/* not lint */
40
41#include "curses.h"
42#include "curses_private.h"
43
44/*
45 * scroll --
46 *	Scroll the window up a line.
47 */
48int
49scroll(WINDOW *win)
50{
51
52	return wscrl(win, 1);
53}
54
55#ifndef _CURSES_USE_MACROS
56
57/*
58 * scrl --
59 *	Scroll stdscr n lines - up if n is positive, down if n is negative.
60 */
61int
62scrl(int nlines)
63{
64
65	return wscrl(stdscr, nlines);
66}
67
68/*
69 * setscrreg --
70 *	Set the top and bottom of the scrolling region for stdscr.
71 */
72int
73setscrreg(int top, int bottom)
74{
75
76	return wsetscrreg(stdscr, top, bottom);
77}
78
79#endif
80
81/*
82 * wscrl --
83 *	Scroll a window n lines - up if n is positive, down if n is negative.
84 */
85int
86wscrl(WINDOW *win, int nlines)
87{
88	int     oy, ox;
89
90	__CTRACE(__CTRACE_WINDOW, "wscrl: (%p) lines=%d\n", win, nlines);
91
92	if (!(win->flags & __SCROLLOK))
93		return ERR;
94	if (!nlines)
95		return OK;
96
97	getyx(win, oy, ox);
98	__CTRACE(__CTRACE_WINDOW, "wscrl: y=%d\n", oy);
99	wmove(win, win->scr_t, 1);
100	winsdelln(win, 0 - nlines);
101	wmove(win, oy, ox);
102
103	if (win == curscr) {
104		__cputchar('\n');
105		if (!__NONL)
106			win->curx = 0;
107		__CTRACE(__CTRACE_WINDOW, "scroll: win == curscr\n");
108	}
109	return OK;
110}
111
112/*
113 * wsetscrreg --
114 *	Set the top and bottom of the scrolling region for win.
115 */
116int
117wsetscrreg(WINDOW *win, int top, int bottom)
118{
119	if (top < 0 || bottom >= win->maxy || bottom - top < 1)
120		return ERR;
121	win->scr_t = top;
122	win->scr_b = bottom;
123	return OK;
124}
125
126/*
127 * has_ic --
128 *	Does the terminal have insert- and delete-character?
129 */
130bool
131has_ic(void)
132{
133
134	if (insert_character != NULL && delete_character != NULL)
135		return true;
136	else
137		return false;
138}
139
140/*
141 * has_ic --
142 *	Does the terminal have insert- and delete-line?
143 */
144bool
145has_il(void)
146{
147	if (insert_line !=NULL && delete_line != NULL)
148		return true;
149	else
150		return false;
151}
152