announce.c revision 8870 
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#ifndef lint
35static char sccsid[] = "@(#)announce.c	8.2 (Berkeley) 1/7/94";
36#endif /* not lint */
37
38#include <sys/types.h>
39#include <sys/uio.h>
40#include <sys/stat.h>
41#include <sys/time.h>
42#include <sys/wait.h>
43#include <sys/socket.h>
44#include <protocols/talkd.h>
45#include <sgtty.h>
46#include <errno.h>
47#include <syslog.h>
48#include <unistd.h>
49#include <stdio.h>
50#include <string.h>
51#include <paths.h>
52
53extern char hostname[];
54
55/*
56 * Announce an invitation to talk.
57 */
58
59/*
60 * See if the user is accepting messages. If so, announce that
61 * a talk is requested.
62 */
63announce(request, remote_machine)
64	CTL_MSG *request;
65	char *remote_machine;
66{
67	char full_tty[32];
68	FILE *tf;
69	struct stat stbuf;
70
71	(void)snprintf(full_tty, sizeof(full_tty),
72	    "%s%s", _PATH_DEV, request->r_tty);
73	if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
74		return (PERMISSION_DENIED);
75	return (print_mesg(request->r_tty, tf, request, remote_machine));
76}
77
78#define max(a,b) ( (a) > (b) ? (a) : (b) )
79#define N_LINES 5
80#define N_CHARS 120
81
82/*
83 * Build a block of characters containing the message.
84 * It is sent blank filled and in a single block to
85 * try to keep the message in one piece if the recipient
86 * in in vi at the time
87 */
88print_mesg(tty, tf, request, remote_machine)
89	char *tty;
90	FILE *tf;
91	CTL_MSG *request;
92	char *remote_machine;
93{
94	struct timeval clock;
95	struct timezone zone;
96	struct tm *localtime();
97	struct tm *localclock;
98	struct iovec iovec;
99	char line_buf[N_LINES][N_CHARS];
100	int sizes[N_LINES];
101	char big_buf[N_LINES*N_CHARS];
102	char *bptr, *lptr, *ttymsg();
103	int i, j, max_size;
104
105	i = 0;
106	max_size = 0;
107	gettimeofday(&clock, &zone);
108	localclock = localtime( &clock.tv_sec );
109	(void)sprintf(line_buf[i], " ");
110	sizes[i] = strlen(line_buf[i]);
111	max_size = max(max_size, sizes[i]);
112	i++;
113	(void)sprintf(line_buf[i], "Message from Talk_Daemon@%s at %d:%02d ...",
114	hostname, localclock->tm_hour , localclock->tm_min );
115	sizes[i] = strlen(line_buf[i]);
116	max_size = max(max_size, sizes[i]);
117	i++;
118	(void)sprintf(line_buf[i], "talk: connection requested by %s@%s",
119		request->l_name, remote_machine);
120	sizes[i] = strlen(line_buf[i]);
121	max_size = max(max_size, sizes[i]);
122	i++;
123	(void)sprintf(line_buf[i], "talk: respond with:  talk %s@%s",
124		request->l_name, remote_machine);
125	sizes[i] = strlen(line_buf[i]);
126	max_size = max(max_size, sizes[i]);
127	i++;
128	(void)sprintf(line_buf[i], " ");
129	sizes[i] = strlen(line_buf[i]);
130	max_size = max(max_size, sizes[i]);
131	i++;
132	bptr = big_buf;
133	*bptr++ = '\007'; /* send something to wake them up */
134	*bptr++ = '\r';	/* add a \r in case of raw mode */
135	*bptr++ = '\n';
136	for (i = 0; i < N_LINES; i++) {
137		/* copy the line into the big buffer */
138		lptr = line_buf[i];
139		while (*lptr != '\0')
140			*(bptr++) = *(lptr++);
141		/* pad out the rest of the lines with blanks */
142		for (j = sizes[i]; j < max_size + 2; j++)
143			*(bptr++) = ' ';
144		*(bptr++) = '\r';	/* add a \r in case of raw mode */
145		*(bptr++) = '\n';
146	}
147	*bptr = '\0';
148	iovec.iov_base = big_buf;
149	iovec.iov_len = bptr - big_buf;
150	/*
151	 * we choose a timeout of RING_WAIT-5 seconds so that we don't
152	 * stack up processes trying to write messages to a tty
153	 * that is permanently blocked.
154	 */
155	if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
156		return (FAILED);
157
158	return (SUCCESS);
159}
160