1 /*	$OpenBSD: wwrint.c,v 1.8 2005/04/13 02:33:09 deraadt Exp $	*/
2 /*	$NetBSD: wwrint.c,v 1.4 1995/12/21 10:46:24 mycroft 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 #ifndef lint
37 #if 0
38 static char sccsid[] = "@(#)wwrint.c	8.1 (Berkeley) 6/6/93";
39 #else
40 static char rcsid[] = "$OpenBSD: wwrint.c,v 1.8 2005/04/13 02:33:09 deraadt Exp $";
41 #endif
42 #endif /* not lint */
43 
44 #include "ww.h"
45 #include "tt.h"
46 #include <sys/types.h>
47 #include <unistd.h>
48 
49 /*
50  * Tty input interrupt handler.
51  * (1) Read input into buffer (wwib*).
52  * (2) Set the interrupt flag if anything is read.
53  * Currently, the last is used to get out of the blocking
54  * select() in wwiomux().
55  * To avoid race conditions, we only modify wwibq in here, except
56  * when the buffer is empty; and everywhere else, we only change wwibp.
57  * It should be completely safe.
58  */
59 void
wwrint()60 wwrint()
61 {
62 	int n;
63 
64 	wwnread++;
65 	n = read(STDIN_FILENO, wwibq, wwibe - wwibq);
66 	if (n > 0) {
67 		if (tt.tt_rint)
68 			n = (*tt.tt_rint)(wwibq, n);
69 		if (n > 0) {
70 			wwibq += n;
71 			wwnreadc += n;
72 			/*
73 			 * Hasten or delay the next checkpoint,
74 			 * as the case may be.
75 			 */
76 			if (tt.tt_checkpoint && !wwdocheckpoint)
77 				(void) alarm(1);
78 			wwsetintr();
79 		}
80 	} else if (n == 0)
81 		wwnreadz++;
82 	else
83 		wwnreade++;
84 }
85