xref: /freebsd/usr.bin/talk/io.c (revision 380a989b3223d455375b4fae70fd0b9bdd43bafb)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  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 #if 0
36 static char sccsid[] = "@(#)io.c	8.1 (Berkeley) 6/6/93";
37 #endif
38 static const char rcsid[] =
39 	"$Id$";
40 #endif /* not lint */
41 
42 /*
43  * This file contains the I/O handling and the exchange of
44  * edit characters. This connection itself is established in
45  * ctl.c
46  */
47 
48 #include <errno.h>
49 #include <string.h>
50 #include "talk.h"
51 
52 #define A_LONG_TIME 10000000
53 
54 /*
55  * The routine to do the actual talking
56  */
57 void
58 talk()
59 {
60 	int nb;
61 	fd_set read_set, read_template;
62 	char buf[BUFSIZ];
63 	struct timeval wait;
64 
65 	message("Connection established");
66 	write(STDOUT_FILENO, "\007\007\007", 3);
67 
68 	current_line = 0;
69 
70 	/*
71 	 * Wait on both the other process (sockt_mask) and
72 	 * standard input ( STDIN_MASK )
73 	 */
74 	FD_ZERO(&read_template);
75 	FD_SET(sockt, &read_template);
76 	FD_SET(fileno(stdin), &read_template);
77 	for (;;) {
78 		read_set = read_template;
79 		wait.tv_sec = A_LONG_TIME;
80 		wait.tv_usec = 0;
81 		nb = select(32, &read_set, 0, 0, &wait);
82 		if (nb <= 0) {
83 			if (errno == EINTR) {
84 				read_set = read_template;
85 				continue;
86 			}
87 			/* panic, we don't know what happened */
88 			p_error("Unexpected error from select");
89 			quit();
90 		}
91 		if (FD_ISSET(sockt, &read_set)) {
92 			/* There is data on sockt */
93 			nb = read(sockt, buf, sizeof buf);
94 			if (nb <= 0) {
95 				message("Connection closed. Exiting");
96 				quit();
97 			}
98 			display(&his_win, buf, nb);
99 		}
100 		if (FD_ISSET(fileno(stdin), &read_set)) {
101 			/*
102 			 * We can't make the tty non_blocking, because
103 			 * curses's output routines would screw up
104 			 */
105 			ioctl(0, FIONREAD, (struct sgttyb *) &nb);
106 			nb = read(0, buf, nb);
107 			display(&my_win, buf, nb);
108 			/* might lose data here because sockt is non-blocking */
109 			write(sockt, buf, nb);
110 		}
111 	}
112 }
113 
114 extern	int errno;
115 extern	int sys_nerr;
116 
117 /*
118  * p_error prints the system error message on the standard location
119  * on the screen and then exits. (i.e. a curses version of perror)
120  */
121 void
122 p_error(string)
123 	char *string;
124 {
125 	wmove(my_win.x_win, current_line, 0);
126 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
127 	    string, strerror(errno), errno);
128 	wrefresh(my_win.x_win);
129 	move(LINES-1, 0);
130 	refresh();
131 	quit();
132 }
133 
134 /*
135  * Display string in the standard location
136  */
137 void
138 message(string)
139 	char *string;
140 {
141 	wmove(my_win.x_win, current_line, 0);
142 	wprintw(my_win.x_win, "[%s]\n", string);
143 	if (current_line < my_win.x_nlines - 1)
144 		current_line++;
145 	wrefresh(my_win.x_win);
146 }
147