xref: /openbsd-src/sys/lib/libsa/cons.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenBSD: cons.c,v 1.9 1997/08/13 14:18:09 niklas 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. All advertising materials mentioning features or use of this software
21  *    must display the following acknowledgement:
22  *	This product includes software developed by the University of
23  *	California, Berkeley and its contributors.
24  * 4. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  *
40  * form: OpenBSD: cons.c,v 1.7 1996/04/21 22:19:48
41  * from: OpenBSD: cninit.c,v 1.2 1996/03/30 02:03:45
42  * from: Utah $Hdr: cons.c 1.7 92/01/21$
43  *
44  *	@(#)cons.c	8.2 (Berkeley) 1/12/94
45  */
46 
47 #include <sys/param.h>
48 #include "stand.h"
49 #include <dev/cons.h>
50 
51 void
52 cninit()
53 {
54 	register struct consdev *cp;
55 
56 	/*
57 	 * Collect information about all possible consoles
58 	 * and find the one with highest priority
59 	 */
60 	for (cp = constab; cp->cn_probe; cp++) {
61 		(*cp->cn_probe)(cp);
62 		if (cp->cn_pri > CN_DEAD &&
63 		    (cn_tab == NULL || cp->cn_pri > cn_tab->cn_pri))
64 			cn_tab = cp;
65 	}
66 	/*
67 	 * No console, we can handle it
68 	 */
69 	if ((cp = cn_tab) == NULL)
70 		return;
71 	/*
72 	 * Turn on console
73 	 */
74 	(*cp->cn_init)(cp);
75 }
76 
77 int
78 cnset(dev)
79 	dev_t dev;
80 {
81 	struct consdev *cp;
82 
83 	/*
84 	 * Look for the specified console device and use it.
85 	 */
86 	for (cp = constab; cp->cn_probe; cp++) {
87 		if (major(cp->cn_dev) == major(dev)) {
88 			/* short-circuit noop */
89 			if (cp == cn_tab && cp->cn_dev == dev)
90 				return (0);
91 			if (cp->cn_pri > CN_DEAD) {
92 				cn_tab = cp;
93 				cp->cn_dev = dev;
94 				/* Turn it on.  */
95 				(cp->cn_init)(cp);
96 				return (0);
97 			}
98 			break;
99 		}
100 	}
101 	return (1);
102 }
103 
104 int
105 cngetc()
106 {
107 	if (cn_tab == NULL)
108 		return (0);
109 	return ((*cn_tab->cn_getc)(cn_tab->cn_dev));
110 }
111 
112 void
113 cnputc(c)
114 	register int c;
115 {
116 	if (cn_tab != NULL && c) {
117 		(*cn_tab->cn_putc)(cn_tab->cn_dev, c);
118 		if (c == '\n')
119 			(*cn_tab->cn_putc)(cn_tab->cn_dev, '\r');
120 	}
121 }
122 
123 int
124 cnischar()
125 {
126 	if (cn_tab != NULL)
127 		return ((*cn_tab->cn_getc)(cn_tab->cn_dev|0x80));
128 	else
129 		return 0;
130 }
131