xref: /netbsd-src/sys/arch/luna68k/stand/boot/awaitkey.c (revision bd88a8a62d4285a4cf7342eed8ea86d7ddc34729)
1 /*	$NetBSD: awaitkey.c,v 1.1 2013/01/21 11:58:12 tsutsui Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 Izumi Tsutsui.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
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  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <lib/libkern/libkern.h>
28 #include <luna68k/stand/boot/samachdep.h>
29 
30 static void print_countdown(const char *, int);
31 
32 #define FMTLEN	40
33 
34 static void
print_countdown(const char * pfmt,int n)35 print_countdown(const char *pfmt, int n)
36 {
37 	int len, i;
38 	char fmtbuf[FMTLEN];
39 
40 	len = snprintf(fmtbuf, FMTLEN, pfmt, n);
41 	printf("%s", fmtbuf);
42 	for (i = 0; i < len; i++)
43 		putchar('\b');
44 }
45 
46 /*
47  * awaitkey(const char *pfmt, int timeout, bool tell)
48  *
49  * Wait timeout seconds until any input from stdin.
50  * print countdown message using "pfmt" if tell is true.
51  * Requires tgetchar(), which returns 0 if there is no input.
52  */
53 char
awaitkey(const char * pfmt,int timeout,bool tell)54 awaitkey(const char *pfmt, int timeout, bool tell)
55 {
56 	uint32_t otick;
57 	char c = 0;
58 
59 	if (timeout <= 0)
60 		goto out;
61 
62 	if (tell)
63 		print_countdown(pfmt, timeout);
64 
65 	otick = tick;
66 
67 	for (;;) {
68 		c = tgetchar();
69 		if (c != 0)
70 			break;
71 		if (tick - otick >= hz) {
72 			otick = tick;
73 			if (--timeout == 0)
74 				break;
75 			if (tell)
76 				print_countdown(pfmt, timeout);
77 		}
78 	}
79 
80  out:
81 	if (tell) {
82 		printf(pfmt, 0);
83 		printf("\n");
84 	}
85 	return c;
86 }
87