1/*	$NetBSD: scroll.c,v 1.21 2009/07/28 18:38:43 christos 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 1.21 2009/07/28 18:38:43 christos 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	return(wscrl(win, 1));
52}
53
54#ifndef _CURSES_USE_MACROS
55
56/*
57 * scrl --
58 *	Scroll stdscr n lines - up if n is positive, down if n is negative.
59 */
60int
61scrl(int nlines)
62{
63	return wscrl(stdscr, nlines);
64}
65
66/*
67 * setscrreg --
68 *	Set the top and bottom of the scrolling region for stdscr.
69 */
70int
71setscrreg(int top, int bottom)
72{
73	return wsetscrreg(stdscr, top, bottom);
74}
75
76#endif
77
78/*
79 * wscrl --
80 *	Scroll a window n lines - up if n is positive, down if n is negative.
81 */
82int
83wscrl(WINDOW *win, int nlines)
84{
85	int     oy, ox;
86
87#ifdef DEBUG
88	__CTRACE(__CTRACE_WINDOW, "wscrl: (%p) lines=%d\n", win, nlines);
89#endif
90
91	if (!(win->flags & __SCROLLOK))
92		return (ERR);
93	if (!nlines)
94		return (OK);
95
96	getyx(win, oy, ox);
97#ifdef DEBUG
98	__CTRACE(__CTRACE_WINDOW, "wscrl: y=%d\n", oy);
99#endif
100	if (oy < win->scr_t || oy > win->scr_b)
101		/* Outside scrolling region */
102		wmove(win, 0, 0);
103	else
104		/* Inside scrolling region */
105		wmove(win, win->scr_t, 0);
106	winsdelln(win, 0 - nlines);
107	wmove(win, oy, ox);
108
109	if (win == curscr) {
110		__cputchar('\n');
111		if (!__NONL)
112			win->curx = 0;
113#ifdef DEBUG
114		__CTRACE(__CTRACE_WINDOW, "scroll: win == curscr\n");
115#endif
116	}
117	return (OK);
118}
119
120/*
121 * wsetscrreg --
122 *	Set the top and bottom of the scrolling region for win.
123 */
124int
125wsetscrreg(WINDOW *win, int top, int bottom)
126{
127	if (top < 0 || bottom >= win->maxy || bottom - top < 1)
128		return (ERR);
129	win->scr_t = top;
130	win->scr_b = bottom;
131	return (OK);
132}
133
134/*
135 * has_ic --
136 *	Does the terminal have insert- and delete-character?
137 */
138bool
139has_ic(void)
140{
141	if (insert_character != NULL && delete_character != NULL)
142		return (TRUE);
143	else
144		return (FALSE);
145}
146
147/*
148 * has_ic --
149 *	Does the terminal have insert- and delete-line?
150 */
151bool
152has_il(void)
153{
154	if (insert_line !=NULL && delete_line != NULL)
155		return (TRUE);
156	else
157		return (FALSE);
158}
159