xref: /freebsd/usr.bin/talk/io.c (revision 4543ef516683042d46f3bd3bb8a4f3f746e00499)
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 
34 /*
35  * This file contains the I/O handling and the exchange of
36  * edit characters. This connection itself is established in
37  * ctl.c
38  */
39 
40 #include <sys/filio.h>
41 
42 #include <errno.h>
43 #include <signal.h>
44 #include <netdb.h>
45 #include <poll.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <unistd.h>
50 #define _XOPEN_SOURCE_EXTENDED
51 #include <curses.h>
52 
53 #include "talk.h"
54 #include "talk_ctl.h"
55 
56 extern void	display(xwin_t *, wchar_t *);
57 
58 volatile sig_atomic_t gotwinch = 0;
59 
60 /*
61  * The routine to do the actual talking
62  */
63 void
64 talk(void)
65 {
66 	struct hostent *hp, *hp2;
67 	struct pollfd fds[2];
68 	int nb;
69 	wchar_t buf[BUFSIZ];
70 	char **addr, *his_machine_name;
71 	FILE *sockfp;
72 
73 	his_machine_name = NULL;
74 	hp = gethostbyaddr((const char *)&his_machine_addr.s_addr,
75 	    sizeof(his_machine_addr.s_addr), AF_INET);
76 	if (hp != NULL) {
77 		hp2 = gethostbyname(hp->h_name);
78 		if (hp2 != NULL && hp2->h_addrtype == AF_INET &&
79 		    hp2->h_length == sizeof(his_machine_addr))
80 			for (addr = hp2->h_addr_list; *addr != NULL; addr++)
81 				if (memcmp(*addr, &his_machine_addr,
82 				    sizeof(his_machine_addr)) == 0) {
83 					his_machine_name = strdup(hp->h_name);
84 					break;
85 				}
86 	}
87 	if (his_machine_name == NULL)
88 		his_machine_name = strdup(inet_ntoa(his_machine_addr));
89 	snprintf((char *)buf, sizeof(buf), "Connection established with %s@%s.",
90 	    msg.r_name, his_machine_name);
91 	free(his_machine_name);
92 	message((char *)buf);
93 	write(STDOUT_FILENO, "\007\007\007", 3);
94 
95 	current_line = 0;
96 
97 	if ((sockfp = fdopen(sockt, "w+")) == NULL)
98 		p_error("fdopen");
99 
100 	setvbuf(sockfp, NULL, _IONBF, 0);
101 	setvbuf(stdin, NULL, _IONBF, 0);
102 
103 	/*
104 	 * Wait on both the other process (sockt) and standard input.
105 	 */
106 	for (;;) {
107 		fds[0].fd = fileno(stdin);
108 		fds[0].events = POLLIN;
109 		fds[1].fd = sockt;
110 		fds[1].events = POLLIN;
111 		nb = poll(fds, 2, INFTIM);
112 		if (gotwinch) {
113 			resize_display();
114 			gotwinch = 0;
115 		}
116 		if (nb <= 0) {
117 			if (errno == EINTR)
118 				continue;
119 			/* Panic, we don't know what happened. */
120 			p_error("Unexpected error from poll");
121 			quit();
122 		}
123 		if (fds[1].revents & POLLIN) {
124 			wint_t w;
125 
126 			/* There is data on sockt. */
127 			w = fgetwc(sockfp);
128 			if (w == WEOF) {
129 				message("Connection closed. Exiting");
130 				quit();
131 			}
132 			display(&his_win, &w);
133 		}
134 		if (fds[0].revents & POLLIN) {
135 			wint_t w;
136 
137 			if ((w = getwchar()) != WEOF) {
138 				display(&my_win, &w);
139 				(void )fputwc(w, sockfp);
140 				(void )fflush(sockfp);
141 			}
142 		}
143 	}
144 }
145 
146 /*
147  * p_error prints the system error message on the standard location
148  * on the screen and then exits. (i.e. a curses version of perror)
149  */
150 void
151 p_error(const char *string)
152 {
153 	wmove(my_win.x_win, current_line, 0);
154 	wprintw(my_win.x_win, "[%s : %s (%d)]\n",
155 	    string, strerror(errno), errno);
156 	wrefresh(my_win.x_win);
157 	move(LINES-1, 0);
158 	refresh();
159 	quit();
160 }
161 
162 /*
163  * Display string in the standard location
164  */
165 void
166 message(const char *string)
167 {
168 	wmove(my_win.x_win, current_line, 0);
169 	wprintw(my_win.x_win, "[%s]\n", string);
170 	if (current_line < my_win.x_nlines - 1)
171 		current_line++;
172 	wrefresh(my_win.x_win);
173 }
174