xref: /freebsd/sys/dev/syscons/snake/snake_saver.c (revision 230f8c40e55e3462e90151e30f61bd0fdd4dcda3)
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  *	$Id$
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 
39 #include <machine/md_var.h>
40 
41 #include "saver.h"
42 
43 MOD_MISC(snake_saver);
44 
45 void (*current_saver)(int blank);
46 void (*old_saver)(int blank);
47 
48 static void
49 snake_saver(int blank)
50 {
51 	const char	saves[] = {"FreeBSD-3.0-CURRENT"};
52 	static u_char	*savs[sizeof(saves)-1];
53 	static int	dirx, diry;
54 	int		f;
55 	scr_stat	*scp = cur_console;
56 
57 	if (blank) {
58 		if (!scrn_blanked) {
59 			fillw((FG_LIGHTGREY|BG_BLACK)<<8 | scr_map[0x20],
60 			      Crtat, scp->xsize * scp->ysize);
61 			set_border(0);
62 			dirx = (scp->xpos ? 1 : -1);
63 			diry = (scp->ypos ?
64 				scp->xsize : -scp->xsize);
65 			for (f=0; f< sizeof(saves)-1; f++)
66 				savs[f] = (u_char *)Crtat + 2 *
67 					  (scp->xpos+scp->ypos*scp->xsize);
68 			*(savs[0]) = scr_map[*saves];
69 			f = scp->ysize * scp->xsize + 5;
70 			outb(crtc_addr, 14);
71 			outb(crtc_addr+1, f >> 8);
72 			outb(crtc_addr, 15);
73 			outb(crtc_addr+1, f & 0xff);
74 			scrn_blanked = 1;
75 		}
76 		if (scrn_blanked++ < 4)
77 			return;
78 		scrn_blanked = 1;
79 		*(savs[sizeof(saves)-2]) = scr_map[0x20];
80 		for (f=sizeof(saves)-2; f > 0; f--)
81 			savs[f] = savs[f-1];
82 		f = (savs[0] - (u_char *)Crtat) / 2;
83 		if ((f % scp->xsize) == 0 ||
84 		    (f % scp->xsize) == scp->xsize - 1 ||
85 		    (random() % 50) == 0)
86 			dirx = -dirx;
87 		if ((f / scp->xsize) == 0 ||
88 		    (f / scp->xsize) == scp->ysize - 1 ||
89 		    (random() % 20) == 0)
90 			diry = -diry;
91 		savs[0] += 2*dirx + 2*diry;
92 		for (f=sizeof(saves)-2; f>=0; f--)
93 			*(savs[f]) = scr_map[saves[f]];
94 	}
95 	else {
96 		if (scrn_blanked) {
97 			set_border(scp->border);
98 			scrn_blanked = 0;
99 			scp->start = 0;
100 			scp->end = scp->xsize * scp->ysize;
101 		}
102 	}
103 }
104 
105 static int
106 snake_saver_load(struct lkm_table *lkmtp, int cmd)
107 {
108 	(*current_saver)(0);
109 	old_saver = current_saver;
110 	current_saver = snake_saver;
111 	return 0;
112 }
113 
114 static int
115 snake_saver_unload(struct lkm_table *lkmtp, int cmd)
116 {
117 	(*current_saver)(0);
118 	current_saver = old_saver;
119 	return 0;
120 }
121 
122 int
123 snake_saver_mod(struct lkm_table *lkmtp, int cmd, int ver)
124 {
125 	DISPATCH(lkmtp, cmd, ver, snake_saver_load, snake_saver_unload,
126 		 lkm_nullcmd);
127 }
128