xref: /freebsd/usr.bin/talk/io.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 
33 #ifndef lint
34 static const char sccsid[] = "@(#)io.c	8.1 (Berkeley) 6/6/93";
35 #endif
36 
37 /*
38  * This file contains the I/O handling and the exchange of
39  * edit characters. This connection itself is established in
40  * ctl.c
41  */
42 
43 #include <sys/filio.h>
44 
45 #include <errno.h>
46 #include <signal.h>
47 #include <netdb.h>
48 #include <poll.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 #define _XOPEN_SOURCE_EXTENDED
54 #include <curses.h>
55 
56 #include "talk.h"
57 #include "talk_ctl.h"
58 
59 extern void	display(xwin_t *, wchar_t *);
60 
61 volatile sig_atomic_t gotwinch = 0;
62 
63 /*
64  * The routine to do the actual talking
65  */
66 void
67 talk(void)
68 {
69 	struct hostent *hp, *hp2;
70 	struct pollfd fds[2];
71 	int nb;
72 	wchar_t buf[BUFSIZ];
73 	char **addr, *his_machine_name;
74 	FILE *sockfp;
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((char *)buf, sizeof(buf), "Connection established with %s@%s.",
93 	    msg.r_name, his_machine_name);
94 	free(his_machine_name);
95 	message((char *)buf);
96 	write(STDOUT_FILENO, "\007\007\007", 3);
97 
98 	current_line = 0;
99 
100 	if ((sockfp = fdopen(sockt, "w+")) == NULL)
101 		p_error("fdopen");
102 
103 	setvbuf(sockfp, NULL, _IONBF, 0);
104 	setvbuf(stdin, NULL, _IONBF, 0);
105 
106 	/*
107 	 * Wait on both the other process (sockt) and standard input.
108 	 */
109 	for (;;) {
110 		fds[0].fd = fileno(stdin);
111 		fds[0].events = POLLIN;
112 		fds[1].fd = sockt;
113 		fds[1].events = POLLIN;
114 		nb = poll(fds, 2, INFTIM);
115 		if (gotwinch) {
116 			resize_display();
117 			gotwinch = 0;
118 		}
119 		if (nb <= 0) {
120 			if (errno == EINTR)
121 				continue;
122 			/* Panic, we don't know what happened. */
123 			p_error("Unexpected error from poll");
124 			quit();
125 		}
126 		if (fds[1].revents & POLLIN) {
127 			wint_t w;
128 
129 			/* There is data on sockt. */
130 			w = fgetwc(sockfp);
131 			if (w == WEOF) {
132 				message("Connection closed. Exiting");
133 				quit();
134 			}
135 			display(&his_win, &w);
136 		}
137 		if (fds[0].revents & POLLIN) {
138 			wint_t w;
139 
140 			if ((w = getwchar()) != WEOF) {
141 				display(&my_win, &w);
142 				(void )fputwc(w, sockfp);
143 				(void )fflush(sockfp);
144 			}
145 		}
146 	}
147 }
148 
149 /*
150  * p_error prints the system error message on the standard location
151  * on the screen and then exits. (i.e. a curses version of perror)
152  */
153 void
154 p_error(const char *string)
155 {
156 	wmove(my_win.x_win, current_line, 0);
157 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
158 	    string, strerror(errno), errno);
159 	wrefresh(my_win.x_win);
160 	move(LINES-1, 0);
161 	refresh();
162 	quit();
163 }
164 
165 /*
166  * Display string in the standard location
167  */
168 void
169 message(const char *string)
170 {
171 	wmove(my_win.x_win, current_line, 0);
172 	wprintw(my_win.x_win, "[%s]\n", string);
173 	if (current_line < my_win.x_nlines - 1)
174 		current_line++;
175 	wrefresh(my_win.x_win);
176 }
177