star_saver.c revision 12276 
1/*-
2 * Copyright (c) 1995 S�ren Schmidt
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software withough specific prior written permission
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 *	$Id: star_saver.c,v 1.5 1995/11/13 07:19:10 bde Exp $
29 */
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/conf.h>
34#include <sys/exec.h>
35#include <sys/sysent.h>
36#include <sys/lkm.h>
37#include <sys/errno.h>
38#include <saver.h>
39
40MOD_MISC(star_saver);
41
42void (*current_saver)(int blank);
43void (*old_saver)(int blank);
44
45#define NUM_STARS	50
46
47/*
48 * Alternate saver that got its inspiration from a well known utility
49 * package for an inferior^H^H^H^H^H^Hfamous OS.
50 */
51static void
52star_saver(int blank)
53{
54	scr_stat	*scp = cur_console;
55	int		cell, i;
56	char 		pattern[] = {"...........++++***   "};
57	char		colors[] = {FG_DARKGREY, FG_LIGHTGREY,
58				    FG_WHITE, FG_LIGHTCYAN};
59	static u_short 	stars[NUM_STARS][2];
60
61	if (blank) {
62		if (!scrn_blanked) {
63			scrn_blanked = 1;
64			fillw((FG_LIGHTGREY|BG_BLACK)<<8|scr_map[0x20], Crtat,
65			      scp->xsize * scp->ysize);
66			set_border(0);
67			for(i=0; i<NUM_STARS; i++) {
68				stars[i][0] =
69					random() % (scp->xsize*scp->ysize);
70				stars[i][1] = 0;
71			}
72		}
73		cell = random() % NUM_STARS;
74		*((u_short*)(Crtat + stars[cell][0])) =
75			scr_map[pattern[stars[cell][1]]] |
76				colors[random()%sizeof(colors)] << 8;
77		if ((stars[cell][1]+=(random()%4)) >= sizeof(pattern)-1) {
78			stars[cell][0] = random() % (scp->xsize*scp->ysize);
79			stars[cell][1] = 0;
80		}
81	}
82	else {
83		if (scrn_blanked) {
84			set_border(scp->border);
85			scrn_blanked = 0;
86			scp->start = 0;
87			scp->end = scp->xsize * scp->ysize;
88		}
89	}
90}
91
92static int
93star_saver_load(struct lkm_table *lkmtp, int cmd)
94{
95	(*current_saver)(0);
96	old_saver = current_saver;
97	current_saver = star_saver;
98	uprintf("star screen saver installed\n");
99	return 0;
100}
101
102static int
103star_saver_unload(struct lkm_table *lkmtp, int cmd)
104{
105	(*current_saver)(0);
106	current_saver = old_saver;
107	uprintf("star screen saver removed\n");
108	return 0;
109}
110
111int
112star_saver_mod(struct lkm_table *lkmtp, int cmd, int ver)
113{
114	DISPATCH(lkmtp, cmd, ver, star_saver_load, star_saver_unload,
115		 lkm_nullcmd);
116}
117