1 /* @(#)wwrint.c 8.1 (Berkeley) 6/6/93 */
2 /* $NetBSD: wwrint.c,v 1.7 2003/08/07 11:17:44 agc Exp $ */
3
4 /*
5 * Copyright (c) 1983, 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 * Edward Wang at The University of California, Berkeley.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #include <unistd.h>
37 #include "ww.h"
38 #include "tt.h"
39
40 /*
41 * Tty input interrupt handler.
42 * (1) Read input into buffer (wwib*).
43 * (2) Set the interrupt flag if anything is read.
44 * Currently, the last is used to get out of the blocking
45 * select() in wwiomux().
46 * To avoid race conditions, we only modify wwibq in here, except
47 * when the buffer is empty; and everywhere else, we only change wwibp.
48 * It should be completely safe.
49 */
50 void
wwrint(void)51 wwrint(void)
52 {
53 int n;
54
55 wwnread++;
56 n = read(0, wwibq, wwibe - wwibq);
57 if (n > 0) {
58 if (tt.tt_rint)
59 n = (*tt.tt_rint)(wwibq, n);
60 if (n > 0) {
61 wwibq += n;
62 wwnreadc += n;
63 /*
64 * Hasten or delay the next checkpoint,
65 * as the case may be.
66 */
67 if (tt.tt_checkpoint && !wwdocheckpoint)
68 (void) alarm(1);
69 wwsetintr();
70 }
71 } else if (n == 0)
72 wwnreadz++;
73 else
74 wwnreade++;
75 }
76