xref: /netbsd-src/usr.bin/talk/io.c (revision ce63d6c20fc4ec8ddc95c84bb229e3c4ecf82b69)
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[] = "@(#)io.c	5.6 (Berkeley) 3/1/91";
36 #endif /* not lint */
37 
38 /*
39  * This file contains the I/O handling and the exchange of
40  * edit characters. This connection itself is established in
41  * ctl.c
42  */
43 
44 #include <sys/time.h>
45 #include "talk.h"
46 #include <stdio.h>
47 #include <errno.h>
48 #include <string.h>
49 
50 #define A_LONG_TIME 10000000
51 #define STDIN_MASK (1<<fileno(stdin))	/* the bit mask for standard
52 					   input */
53 
54 /*
55  * The routine to do the actual talking
56  */
57 talk()
58 {
59 	register int read_template, sockt_mask;
60 	int read_set, nb;
61 	char buf[BUFSIZ];
62 	struct timeval wait;
63 
64 	message("Connection established\007\007\007");
65 	current_line = 0;
66 	sockt_mask = (1<<sockt);
67 
68 	/*
69 	 * Wait on both the other process (sockt_mask) and
70 	 * standard input ( STDIN_MASK )
71 	 */
72 	read_template = sockt_mask | STDIN_MASK;
73 	for (;;) {
74 		read_set = read_template;
75 		wait.tv_sec = A_LONG_TIME;
76 		wait.tv_usec = 0;
77 		nb = select(32, &read_set, 0, 0, &wait);
78 		if (nb <= 0) {
79 			if (errno == EINTR) {
80 				read_set = read_template;
81 				continue;
82 			}
83 			/* panic, we don't know what happened */
84 			p_error("Unexpected error from select");
85 			quit();
86 		}
87 		if (read_set & sockt_mask) {
88 			/* There is data on sockt */
89 			nb = read(sockt, buf, sizeof buf);
90 			if (nb <= 0) {
91 				message("Connection closed. Exiting");
92 				quit();
93 			}
94 			display(&his_win, buf, nb);
95 		}
96 		if (read_set & STDIN_MASK) {
97 			/*
98 			 * We can't make the tty non_blocking, because
99 			 * curses's output routines would screw up
100 			 */
101 			ioctl(0, FIONREAD, (struct sgttyb *) &nb);
102 			nb = read(0, buf, nb);
103 			display(&my_win, buf, nb);
104 			/* might lose data here because sockt is non-blocking */
105 			write(sockt, buf, nb);
106 		}
107 	}
108 }
109 
110 extern	int errno;
111 extern	int sys_nerr;
112 
113 /*
114  * p_error prints the system error message on the standard location
115  * on the screen and then exits. (i.e. a curses version of perror)
116  */
117 p_error(string)
118 	char *string;
119 {
120 	wmove(my_win.x_win, current_line%my_win.x_nlines, 0);
121 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
122 	    string, strerror(errno), errno);
123 	wrefresh(my_win.x_win);
124 	move(LINES-1, 0);
125 	refresh();
126 	quit();
127 }
128 
129 /*
130  * Display string in the standard location
131  */
132 message(string)
133 	char *string;
134 {
135 
136 	wmove(my_win.x_win, current_line%my_win.x_nlines, 0);
137 	wprintw(my_win.x_win, "[%s]\n", string);
138 	wrefresh(my_win.x_win);
139 }
140