scroll.c revision 1.23 1 /* $NetBSD: scroll.c,v 1.23 2017/01/06 13:53:18 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 1.23 2017/01/06 13:53:18 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
49 scroll(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 */
61 int
62 scrl(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 */
72 int
73 setscrreg(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 */
85 int
86 wscrl(WINDOW *win, int nlines)
87 {
88 int oy, ox;
89
90 #ifdef DEBUG
91 __CTRACE(__CTRACE_WINDOW, "wscrl: (%p) lines=%d\n", win, nlines);
92 #endif
93
94 if (!(win->flags & __SCROLLOK))
95 return ERR;
96 if (!nlines)
97 return OK;
98
99 getyx(win, oy, ox);
100 #ifdef DEBUG
101 __CTRACE(__CTRACE_WINDOW, "wscrl: y=%d\n", oy);
102 #endif
103 if (oy < win->scr_t || oy > win->scr_b)
104 /* Outside scrolling region */
105 wmove(win, 0, 0);
106 else
107 /* Inside scrolling region */
108 wmove(win, win->scr_t, 0);
109 winsdelln(win, 0 - nlines);
110 wmove(win, oy, ox);
111
112 if (win == curscr) {
113 __cputchar('\n');
114 if (!__NONL)
115 win->curx = 0;
116 #ifdef DEBUG
117 __CTRACE(__CTRACE_WINDOW, "scroll: win == curscr\n");
118 #endif
119 }
120 return OK;
121 }
122
123 /*
124 * wsetscrreg --
125 * Set the top and bottom of the scrolling region for win.
126 */
127 int
128 wsetscrreg(WINDOW *win, int top, int bottom)
129 {
130 if (top < 0 || bottom >= win->maxy || bottom - top < 1)
131 return ERR;
132 win->scr_t = top;
133 win->scr_b = bottom;
134 return OK;
135 }
136
137 /*
138 * has_ic --
139 * Does the terminal have insert- and delete-character?
140 */
141 bool
142 has_ic(void)
143 {
144
145 if (insert_character != NULL && delete_character != NULL)
146 return true;
147 else
148 return false;
149 }
150
151 /*
152 * has_ic --
153 * Does the terminal have insert- and delete-line?
154 */
155 bool
156 has_il(void)
157 {
158 if (insert_line !=NULL && delete_line != NULL)
159 return true;
160 else
161 return false;
162 }
163