xref: /freebsd/usr.bin/talk/io.c (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
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 #include <sys/cdefs.h>
35 
36 __FBSDID("$FreeBSD$");
37 
38 #ifndef lint
39 static const char sccsid[] = "@(#)io.c	8.1 (Berkeley) 6/6/93";
40 #endif
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 <sys/filio.h>
49 
50 #include <errno.h>
51 #include <signal.h>
52 #include <netdb.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 
57 #include "talk.h"
58 #include "talk_ctl.h"
59 
60 #define A_LONG_TIME 10000000
61 
62 volatile sig_atomic_t gotwinch = 0;
63 
64 /*
65  * The routine to do the actual talking
66  */
67 void
68 talk()
69 {
70 	struct hostent *hp, *hp2;
71 	int nb;
72 	fd_set read_set, read_template;
73 	char buf[BUFSIZ], **addr, *his_machine_name;
74 	struct timeval wait;
75 
76 	his_machine_name = NULL;
77 	hp = gethostbyaddr((const char *)&his_machine_addr.s_addr,
78 	    sizeof(his_machine_addr.s_addr), AF_INET);
79 	if (hp != NULL) {
80 		hp2 = gethostbyname(hp->h_name);
81 		if (hp2 != NULL && hp2->h_addrtype == AF_INET &&
82 		    hp2->h_length == sizeof(his_machine_addr))
83 			for (addr = hp2->h_addr_list; *addr != NULL; addr++)
84 				if (memcmp(*addr, &his_machine_addr,
85 				    sizeof(his_machine_addr)) == 0) {
86 					his_machine_name = strdup(hp->h_name);
87 					break;
88 				}
89 	}
90 	if (his_machine_name == NULL)
91 		his_machine_name = strdup(inet_ntoa(his_machine_addr));
92 	snprintf(buf, sizeof(buf), "Connection established with %s@%s.",
93 	    msg.r_name, his_machine_name);
94 	free(his_machine_name);
95 	message(buf);
96 	write(STDOUT_FILENO, "\007\007\007", 3);
97 
98 	current_line = 0;
99 
100 	/*
101 	 * Wait on both the other process (sockt_mask) and
102 	 * standard input ( STDIN_MASK )
103 	 */
104 	FD_ZERO(&read_template);
105 	FD_SET(sockt, &read_template);
106 	FD_SET(fileno(stdin), &read_template);
107 	for (;;) {
108 		read_set = read_template;
109 		wait.tv_sec = A_LONG_TIME;
110 		wait.tv_usec = 0;
111 		nb = select(32, &read_set, 0, 0, &wait);
112 		if (gotwinch) {
113 			resize_display();
114 			gotwinch = 0;
115 		}
116 		if (nb <= 0) {
117 			if (errno == EINTR) {
118 				read_set = read_template;
119 				continue;
120 			}
121 			/* panic, we don't know what happened */
122 			p_error("Unexpected error from select");
123 			quit();
124 		}
125 		if (FD_ISSET(sockt, &read_set)) {
126 			/* There is data on sockt */
127 			nb = read(sockt, buf, sizeof buf);
128 			if (nb <= 0) {
129 				message("Connection closed. Exiting");
130 				quit();
131 			}
132 			display(&his_win, buf, nb);
133 		}
134 		if (FD_ISSET(fileno(stdin), &read_set)) {
135 			/*
136 			 * We can't make the tty non_blocking, because
137 			 * curses's output routines would screw up
138 			 */
139 			int i;
140 			ioctl(0, FIONREAD, (void *) &nb);
141 			if (nb > sizeof buf)
142 				nb = sizeof buf;
143 			nb = read(STDIN_FILENO, buf, nb);
144 			display(&my_win, buf, nb);
145 			/* might lose data here because sockt is non-blocking */
146 			for (i = 0; i < nb; ++i)
147 				if (buf[i] == '\r')
148 					buf[i] = '\n';
149 			write(sockt, buf, nb);
150 		}
151 	}
152 }
153 
154 /*
155  * p_error prints the system error message on the standard location
156  * on the screen and then exits. (i.e. a curses version of perror)
157  */
158 void
159 p_error(string)
160 	const char *string;
161 {
162 	wmove(my_win.x_win, current_line, 0);
163 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
164 	    string, strerror(errno), errno);
165 	wrefresh(my_win.x_win);
166 	move(LINES-1, 0);
167 	refresh();
168 	quit();
169 }
170 
171 /*
172  * Display string in the standard location
173  */
174 void
175 message(string)
176 	const char *string;
177 {
178 	wmove(my_win.x_win, current_line, 0);
179 	wprintw(my_win.x_win, "[%s]\n", string);
180 	if (current_line < my_win.x_nlines - 1)
181 		current_line++;
182 	wrefresh(my_win.x_win);
183 }
184