xref: /netbsd-src/usr.bin/talk/io.c (revision 0b9f50897e9a9c6709320fafb4c3787fddcc0a45)
1 /*
2  * Copyright (c) 1983 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /*static char sccsid[] = "from: @(#)io.c	5.6 (Berkeley) 3/1/91";*/
36 static char rcsid[] = "$Id: io.c,v 1.3 1993/08/14 13:47:51 mycroft Exp $";
37 #endif /* not lint */
38 
39 /*
40  * This file contains the I/O handling and the exchange of
41  * edit characters. This connection itself is established in
42  * ctl.c
43  */
44 
45 #include <sys/time.h>
46 #include <sys/ioctl.h>
47 #include "talk.h"
48 #include <stdio.h>
49 #include <errno.h>
50 #include <string.h>
51 
52 #define A_LONG_TIME 10000000
53 #define STDIN_MASK (1<<fileno(stdin))	/* the bit mask for standard
54 					   input */
55 
56 /*
57  * The routine to do the actual talking
58  */
59 talk()
60 {
61 	register int read_template, sockt_mask;
62 	int read_set, nb;
63 	char buf[BUFSIZ];
64 	struct timeval wait;
65 
66 	message("Connection established\007\007\007");
67 	current_line = 0;
68 	sockt_mask = (1<<sockt);
69 
70 	/*
71 	 * Wait on both the other process (sockt_mask) and
72 	 * standard input ( STDIN_MASK )
73 	 */
74 	read_template = sockt_mask | STDIN_MASK;
75 	for (;;) {
76 		read_set = read_template;
77 		wait.tv_sec = A_LONG_TIME;
78 		wait.tv_usec = 0;
79 		nb = select(32, &read_set, 0, 0, &wait);
80 		if (nb <= 0) {
81 			if (errno == EINTR) {
82 				read_set = read_template;
83 				continue;
84 			}
85 			/* panic, we don't know what happened */
86 			p_error("Unexpected error from select");
87 			quit();
88 		}
89 		if (read_set & sockt_mask) {
90 			/* There is data on sockt */
91 			nb = read(sockt, buf, sizeof buf);
92 			if (nb <= 0) {
93 				message("Connection closed. Exiting");
94 				quit();
95 			}
96 			display(&his_win, buf, nb);
97 		}
98 		if (read_set & STDIN_MASK) {
99 			/*
100 			 * We can't make the tty non_blocking, because
101 			 * curses's output routines would screw up
102 			 */
103 			ioctl(0, FIONREAD, (struct sgttyb *) &nb);
104 			nb = read(0, buf, nb);
105 			display(&my_win, buf, nb);
106 			/* might lose data here because sockt is non-blocking */
107 			write(sockt, buf, nb);
108 		}
109 	}
110 }
111 
112 extern	int errno;
113 extern	int sys_nerr;
114 
115 /*
116  * p_error prints the system error message on the standard location
117  * on the screen and then exits. (i.e. a curses version of perror)
118  */
119 p_error(string)
120 	char *string;
121 {
122 	wmove(my_win.x_win, current_line%my_win.x_nlines, 0);
123 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
124 	    string, strerror(errno), errno);
125 	wrefresh(my_win.x_win);
126 	move(LINES-1, 0);
127 	refresh();
128 	quit();
129 }
130 
131 /*
132  * Display string in the standard location
133  */
134 message(string)
135 	char *string;
136 {
137 
138 	wmove(my_win.x_win, current_line%my_win.x_nlines, 0);
139 	wprintw(my_win.x_win, "[%s]\n", string);
140 	wrefresh(my_win.x_win);
141 }
142