xref: /netbsd-src/libexec/talkd/announce.c (revision fdecd6a253f999ae92b139670d9e15cc9df4497c)
1 /*	$NetBSD: announce.c,v 1.8 1997/06/29 19:13:02 christos Exp $	*/
2 
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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/cdefs.h>
37 #ifndef lint
38 #if 0
39 static char sccsid[] = "@(#)announce.c	8.3 (Berkeley) 4/28/95";
40 #else
41 __RCSID("$NetBSD: announce.c,v 1.8 1997/06/29 19:13:02 christos Exp $");
42 #endif
43 #endif /* not lint */
44 
45 #include <sys/types.h>
46 #include <sys/uio.h>
47 #include <sys/stat.h>
48 #include <sys/time.h>
49 #include <sys/wait.h>
50 #include <sys/socket.h>
51 #include <protocols/talkd.h>
52 #include <errno.h>
53 #include <syslog.h>
54 #include <unistd.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <vis.h>
59 #include <paths.h>
60 #include <util.h>
61 #include "extern.h"
62 
63 extern char hostname[];
64 
65 /*
66  * Announce an invitation to talk.
67  */
68 
69 /*
70  * See if the user is accepting messages. If so, announce that
71  * a talk is requested.
72  */
73 int
74 announce(request, remote_machine)
75 	CTL_MSG *request;
76 	char *remote_machine;
77 {
78 	char full_tty[32];
79 	struct stat stbuf;
80 
81 	(void)snprintf(full_tty, sizeof(full_tty),
82 	    "%s%s", _PATH_DEV, request->r_tty);
83 	if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
84 		return (PERMISSION_DENIED);
85 	return (print_mesg(request->r_tty, request, remote_machine));
86 }
87 
88 #define max(a,b) ( (a) > (b) ? (a) : (b) )
89 #define N_LINES 5
90 #define N_CHARS 256
91 
92 /*
93  * Build a block of characters containing the message.
94  * It is sent blank filled and in a single block to
95  * try to keep the message in one piece if the recipient
96  * in in vi at the time
97  */
98 int
99 print_mesg(tty, request, remote_machine)
100 	char *tty;
101 	CTL_MSG *request;
102 	char *remote_machine;
103 {
104 	struct timeval clock;
105 	time_t clocktime;
106 	struct timezone zone;
107 	struct tm *localclock;
108 	struct iovec iovec;
109 	char line_buf[N_LINES][N_CHARS];
110 	int sizes[N_LINES];
111 	char big_buf[N_LINES*N_CHARS];
112 	char *bptr, *lptr, *vis_user;
113 	int i, j, max_size;
114 
115 	i = 0;
116 	max_size = 0;
117 	gettimeofday(&clock, &zone);
118 	clocktime = clock.tv_sec;
119 	localclock = localtime(&clocktime);
120 	(void)snprintf(line_buf[i], N_CHARS, " ");
121 	sizes[i] = strlen(line_buf[i]);
122 	max_size = max(max_size, sizes[i]);
123 	i++;
124 	(void)snprintf(line_buf[i], N_CHARS,
125 	    "Message from Talk_Daemon@%s at %d:%02d ...",
126 	    hostname, localclock->tm_hour , localclock->tm_min );
127 	sizes[i] = strlen(line_buf[i]);
128 	max_size = max(max_size, sizes[i]);
129 	i++;
130 	vis_user = (char *) malloc(strlen(request->l_name) * 4 + 1);
131 	strvis(vis_user, request->l_name, VIS_CSTYLE);
132 	(void)snprintf(line_buf[i], N_CHARS,
133 	    "talk: connection requested by %s@%s.", vis_user, remote_machine);
134 	sizes[i] = strlen(line_buf[i]);
135 	max_size = max(max_size, sizes[i]);
136 	i++;
137 	(void)snprintf(line_buf[i], N_CHARS,
138 	    "talk: respond with:  talk %s@%s", vis_user, remote_machine);
139 	sizes[i] = strlen(line_buf[i]);
140 	max_size = max(max_size, sizes[i]);
141 	i++;
142 	(void)snprintf(line_buf[i], N_CHARS, " ");
143 	sizes[i] = strlen(line_buf[i]);
144 	max_size = max(max_size, sizes[i]);
145 	i++;
146 	bptr = big_buf;
147 	*bptr++ = ''; /* send something to wake them up */
148 	*bptr++ = '\r';	/* add a \r in case of raw mode */
149 	*bptr++ = '\n';
150 	for (i = 0; i < N_LINES; i++) {
151 		/* copy the line into the big buffer */
152 		lptr = line_buf[i];
153 		while (*lptr != '\0')
154 			*(bptr++) = *(lptr++);
155 		/* pad out the rest of the lines with blanks */
156 		for (j = sizes[i]; j < max_size + 2; j++)
157 			*(bptr++) = ' ';
158 		*(bptr++) = '\r';	/* add a \r in case of raw mode */
159 		*(bptr++) = '\n';
160 	}
161 	*bptr = '\0';
162 	iovec.iov_base = big_buf;
163 	iovec.iov_len = bptr - big_buf;
164 	/*
165 	 * we choose a timeout of RING_WAIT-5 seconds so that we don't
166 	 * stack up processes trying to write messages to a tty
167 	 * that is permanently blocked.
168 	 */
169 	if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
170 		return (FAILED);
171 
172 	return (SUCCESS);
173 }
174