xref: /minix3/lib/libcurses/scroll.c (revision 51ffecc181005cb45a40108612ee28d1daaeeb86)
1 /*	$NetBSD: scroll.c,v 1.22 2010/02/03 15:34:40 roy 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
35 static char sccsid[] = "@(#)scroll.c	8.3 (Berkeley) 5/4/94";
36 #else
37 __RCSID("$NetBSD: scroll.c,v 1.22 2010/02/03 15:34:40 roy 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  */
48 int
scroll(WINDOW * win)49 scroll(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  */
60 int
scrl(int nlines)61 scrl(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  */
70 int
setscrreg(int top,int bottom)71 setscrreg(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  */
82 int
wscrl(WINDOW * win,int nlines)83 wscrl(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  */
124 int
wsetscrreg(WINDOW * win,int top,int bottom)125 wsetscrreg(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  */
138 bool
has_ic(void)139 has_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  */
151 bool
has_il(void)152 has_il(void)
153 {
154 	if (insert_line !=NULL && delete_line != NULL)
155 		return (TRUE);
156 	else
157 		return (FALSE);
158 }
159