xref: /freebsd/usr.bin/talk/io.c (revision bdd1243df58e60e85101c09001d9812a789b6bc4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 
34 __FBSDID("$FreeBSD$");
35 
36 #ifndef lint
37 static const char sccsid[] = "@(#)io.c	8.1 (Berkeley) 6/6/93";
38 #endif
39 
40 /*
41  * This file contains the I/O handling and the exchange of
42  * edit characters. This connection itself is established in
43  * ctl.c
44  */
45 
46 #include <sys/filio.h>
47 
48 #include <errno.h>
49 #include <signal.h>
50 #include <netdb.h>
51 #include <poll.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #define _XOPEN_SOURCE_EXTENDED
57 #include <curses.h>
58 
59 #include "talk.h"
60 #include "talk_ctl.h"
61 
62 extern void	display(xwin_t *, wchar_t *);
63 
64 volatile sig_atomic_t gotwinch = 0;
65 
66 /*
67  * The routine to do the actual talking
68  */
69 void
70 talk(void)
71 {
72 	struct hostent *hp, *hp2;
73 	struct pollfd fds[2];
74 	int nb;
75 	wchar_t buf[BUFSIZ];
76 	char **addr, *his_machine_name;
77 	FILE *sockfp;
78 
79 	his_machine_name = NULL;
80 	hp = gethostbyaddr((const char *)&his_machine_addr.s_addr,
81 	    sizeof(his_machine_addr.s_addr), AF_INET);
82 	if (hp != NULL) {
83 		hp2 = gethostbyname(hp->h_name);
84 		if (hp2 != NULL && hp2->h_addrtype == AF_INET &&
85 		    hp2->h_length == sizeof(his_machine_addr))
86 			for (addr = hp2->h_addr_list; *addr != NULL; addr++)
87 				if (memcmp(*addr, &his_machine_addr,
88 				    sizeof(his_machine_addr)) == 0) {
89 					his_machine_name = strdup(hp->h_name);
90 					break;
91 				}
92 	}
93 	if (his_machine_name == NULL)
94 		his_machine_name = strdup(inet_ntoa(his_machine_addr));
95 	snprintf((char *)buf, sizeof(buf), "Connection established with %s@%s.",
96 	    msg.r_name, his_machine_name);
97 	free(his_machine_name);
98 	message((char *)buf);
99 	write(STDOUT_FILENO, "\007\007\007", 3);
100 
101 	current_line = 0;
102 
103 	if ((sockfp = fdopen(sockt, "w+")) == NULL)
104 		p_error("fdopen");
105 
106 	setvbuf(sockfp, NULL, _IONBF, 0);
107 	setvbuf(stdin, NULL, _IONBF, 0);
108 
109 	/*
110 	 * Wait on both the other process (sockt) and standard input.
111 	 */
112 	for (;;) {
113 		fds[0].fd = fileno(stdin);
114 		fds[0].events = POLLIN;
115 		fds[1].fd = sockt;
116 		fds[1].events = POLLIN;
117 		nb = poll(fds, 2, INFTIM);
118 		if (gotwinch) {
119 			resize_display();
120 			gotwinch = 0;
121 		}
122 		if (nb <= 0) {
123 			if (errno == EINTR)
124 				continue;
125 			/* Panic, we don't know what happened. */
126 			p_error("Unexpected error from poll");
127 			quit();
128 		}
129 		if (fds[1].revents & POLLIN) {
130 			wint_t w;
131 
132 			/* There is data on sockt. */
133 			w = fgetwc(sockfp);
134 			if (w == WEOF) {
135 				message("Connection closed. Exiting");
136 				quit();
137 			}
138 			display(&his_win, &w);
139 		}
140 		if (fds[0].revents & POLLIN) {
141 			wint_t w;
142 
143 			if ((w = getwchar()) != WEOF) {
144 				display(&my_win, &w);
145 				(void )fputwc(w, sockfp);
146 				(void )fflush(sockfp);
147 			}
148 		}
149 	}
150 }
151 
152 /*
153  * p_error prints the system error message on the standard location
154  * on the screen and then exits. (i.e. a curses version of perror)
155  */
156 void
157 p_error(const char *string)
158 {
159 	wmove(my_win.x_win, current_line, 0);
160 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
161 	    string, strerror(errno), errno);
162 	wrefresh(my_win.x_win);
163 	move(LINES-1, 0);
164 	refresh();
165 	quit();
166 }
167 
168 /*
169  * Display string in the standard location
170  */
171 void
172 message(const char *string)
173 {
174 	wmove(my_win.x_win, current_line, 0);
175 	wprintw(my_win.x_win, "[%s]\n", string);
176 	if (current_line < my_win.x_nlines - 1)
177 		current_line++;
178 	wrefresh(my_win.x_win);
179 }
180