1 /* $OpenBSD: cons.c,v 1.11 2003/08/11 06:23:09 deraadt Exp $ */
2
3 /*
4 * Copyright (c) 1988 University of Utah.
5 * Copyright (c) 1990, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * the Systems Programming Group of the University of Utah Computer
10 * Science Department.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. 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.
23 *
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
34 * SUCH DAMAGE.
35 *
36 * form: OpenBSD: cons.c,v 1.7 1996/04/21 22:19:48
37 * from: OpenBSD: cninit.c,v 1.2 1996/03/30 02:03:45
38 * from: Utah $Hdr: cons.c 1.7 92/01/21$
39 *
40 * @(#)cons.c 8.2 (Berkeley) 1/12/94
41 */
42
43 #include <sys/param.h>
44 #include "stand.h"
45 #include <dev/cons.h>
46
47 void
48 cninit(void)
49 {
50 struct consdev *cp;
51
52 /*
53 * Collect information about all possible consoles
54 * and find the one with highest priority
55 */
56 for (cp = constab; cp->cn_probe; cp++) {
57 (*cp->cn_probe)(cp);
58 if (cp->cn_pri > CN_DEAD &&
59 (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
60 cn_tab = cp;
61 }
62 /*
63 * No console, we can handle it
64 */
65 if ((cp = cn_tab) == NULL)
66 return;
67 /*
68 * Turn on console
69 */
70 (*cp->cn_init)(cp);
71 }
72
73 int
74 cnset(dev_t dev)
75 {
76 struct consdev *cp;
77
78 /*
79 * Look for the specified console device and use it.
80 */
81 for (cp = constab; cp->cn_probe; cp++) {
82 if (major(cp->cn_dev) == major(dev)) {
83 /* short-circuit noop */
84 if (cp == cn_tab && cp->cn_dev == dev)
85 return (0);
86 if (cp->cn_pri > CN_DEAD) {
87 cn_tab = cp;
88 cp->cn_dev = dev;
89 /* Turn it on. */
90 (cp->cn_init)(cp);
91 return (0);
92 }
93 break;
94 }
95 }
96 return (1);
97 }
98
99 int
100 cngetc(void)
101 {
102 if (cn_tab == NULL)
103 return (0);
104 return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
105 }
106
107 void
108 cnputc(int c)
109 {
110 if (cn_tab != NULL && c) {
111 (*cn_tab->cn_putc)(cn_tab->cn_dev, c);
112 if (c == '\n')
113 (*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
114 }
115 }
116
117 int
118 cnischar(void)
119 {
120 if (cn_tab != NULL)
121 return ((*cn_tab->cn_getc)(cn_tab->cn_dev|0x80));
122 return 0;
123 }