2 * Copyright (c) 1983, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Edward Wang at The University of California, Berkeley.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * @(#)wwscroll.c 8.1 (Berkeley) 6/6/93
37 * $FreeBSD: src/usr.bin/window/wwscroll.c,v 1.1.1.1.14.1 2001/05/17 09:45:01 obrien Exp $
38 * $DragonFly: src/usr.bin/window/wwscroll.c,v 1.2 2003/06/17 04:29:34 dillon Exp $
45 register struct ww
*w
;
57 else if (top
+ w
->ww_b
.nr
< w
->ww_w
.b
)
58 top
= w
->ww_w
.b
- w
->ww_b
.nr
;
59 n
= abs(top
- w
->ww_b
.t
);
62 (void) wwscroll1(w
, w
->ww_i
.t
, w
->ww_i
.b
, dir
, 0);
68 w
->ww_buf
-= top
- w
->ww_b
.t
;
70 w
->ww_b
.b
= top
+ w
->ww_b
.nr
;
76 * Scroll one line, between 'row1' and 'row2', in direction 'dir'.
77 * Don't adjust ww_scroll.
78 * And don't redraw 'leaveit' lines.
80 wwscroll1(w
, row1
, row2
, dir
, leaveit
)
81 register struct ww
*w
;
92 * See how many lines on the screen are affected.
93 * And calculate row1x, row2x, and left at the same time.
95 for (i
= row1
; i
< row2
&& w
->ww_nvis
[i
] == 0; i
++)
97 if (i
>= row2
) /* can't do any fancy stuff */
100 for (i
= row2
- 1; i
>= row1
&& w
->ww_nvis
[i
] == 0; i
--)
103 goto out
; /* just one line is easy */
107 * See how much of this window is visible.
109 nvismax
= wwncol
* (row2x
- row1x
);
111 for (i
= row1x
; i
< row2x
; i
++)
112 nvis
+= w
->ww_nvis
[i
];
115 * If it's a good idea to scroll and the terminal can, then do it.
117 if (nvis
< nvismax
/ 2)
118 goto no_scroll
; /* not worth it */
119 if ((dir
> 0 ? tt
.tt_scroll_down
== 0 : tt
.tt_scroll_up
== 0) ||
120 (tt
.tt_scroll_top
!= row1x
|| tt
.tt_scroll_bot
!= row2x
- 1) &&
121 tt
.tt_setscroll
== 0)
122 if (tt
.tt_delline
== 0 || tt
.tt_insline
== 0)
124 xxscroll(dir
, row1x
, row2x
);
127 * Fix up the old screen.
130 register union ww_char
*tmp
;
131 register union ww_char
**cpp
, **cqq
;
137 for (i
= row2x
- row1x
; --i
> 0;)
144 for (i
= row2x
- row1x
; --i
> 0;)
148 for (i
= wwncol
; --i
>= 0;)
154 * Fix the new screen.
156 if (nvis
== nvismax
) {
158 * Can shift whole lines.
162 register union ww_char
*tmp
;
163 register union ww_char
**cpp
, **cqq
;
168 for (i
= row2x
- row1x
; --i
> 0;)
173 register char *p
, *q
;
175 p
= &wwtouched
[row1x
];
177 for (i
= row2x
- row1x
; --i
> 0;)
183 p
= &wwtouched
[row1x
];
184 for (i
= row2x
- row1x
; --i
>= 0;)
187 wwredrawwin1(w
, row1
, row1x
, dir
);
188 wwredrawwin1(w
, row2x
- 1, row2
- leaveit
, dir
);
191 register union ww_char
*tmp
;
192 register union ww_char
**cpp
, **cqq
;
197 for (i
= row2x
- row1x
; --i
> 0;)
202 register char *p
, *q
;
204 p
= &wwtouched
[row2x
];
206 for (i
= row2x
- row1x
; --i
> 0;)
212 p
= &wwtouched
[row1x
];
213 for (i
= row2x
- row1x
; --i
>= 0;)
216 wwredrawwin1(w
, row1
+ leaveit
, row1x
+ 1, dir
);
217 wwredrawwin1(w
, row2x
, row2
, dir
);
223 p
= &wwtouched
[row1x
];
224 for (i
= row2x
- row1x
; --i
>= 0;)
229 wwredrawwin1(w
, row1
, row2
- leaveit
, dir
);
231 wwredrawwin1(w
, row1
+ leaveit
, row2
, dir
);