announce.c revision 21838 
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 *	$FreeBSD: head/libexec/talkd/announce.c 21838 1997-01-18 08:30:01Z pst $
34 */
35
36#ifndef lint
37static char sccsid[] = "@(#)announce.c	8.3 (Berkeley) 4/28/95";
38#endif /* not lint */
39
40#include <sys/types.h>
41#include <sys/uio.h>
42#include <sys/stat.h>
43#include <sys/time.h>
44#include <sys/wait.h>
45#include <sys/socket.h>
46
47#include <protocols/talkd.h>
48
49#include <errno.h>
50#include <paths.h>
51#include <stdio.h>
52#include <stdlib.h>
53#include <string.h>
54#include <syslog.h>
55#include <unistd.h>
56#include <vis.h>
57
58extern char hostname[];
59
60/*
61 * Announce an invitation to talk.
62 */
63
64/*
65 * See if the user is accepting messages. If so, announce that
66 * a talk is requested.
67 */
68announce(request, remote_machine)
69	CTL_MSG *request;
70	char *remote_machine;
71{
72	char full_tty[32];
73	FILE *tf;
74	struct stat stbuf;
75
76	(void)snprintf(full_tty, sizeof(full_tty),
77	    "%s%s", _PATH_DEV, request->r_tty);
78	if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
79		return (PERMISSION_DENIED);
80	return (print_mesg(request->r_tty, tf, request, remote_machine));
81}
82
83#define max(a,b) ( (a) > (b) ? (a) : (b) )
84#define N_LINES 5
85#define N_CHARS 256
86
87/*
88 * Build a block of characters containing the message.
89 * It is sent blank filled and in a single block to
90 * try to keep the message in one piece if the recipient
91 * in in vi at the time
92 */
93print_mesg(tty, tf, request, remote_machine)
94	char *tty;
95	FILE *tf;
96	CTL_MSG *request;
97	char *remote_machine;
98{
99	struct timeval clock;
100	struct timezone zone;
101	struct tm *localtime();
102	struct tm *localclock;
103	struct iovec iovec;
104	char line_buf[N_LINES][N_CHARS];
105	int sizes[N_LINES];
106	char big_buf[N_LINES*N_CHARS];
107	char *bptr, *lptr, *vis_user;
108	int i, j, max_size;
109
110	i = 0;
111	max_size = 0;
112	gettimeofday(&clock, &zone);
113	localclock = localtime( &clock.tv_sec );
114	(void)snprintf(line_buf[i], N_CHARS, " ");
115	sizes[i] = strlen(line_buf[i]);
116	max_size = max(max_size, sizes[i]);
117	i++;
118	(void)snprintf(line_buf[i], N_CHARS,
119		"Message from Talk_Daemon@%s at %d:%02d ...",
120		hostname, localclock->tm_hour , localclock->tm_min );
121	sizes[i] = strlen(line_buf[i]);
122	max_size = max(max_size, sizes[i]);
123	i++;
124
125	vis_user = malloc(strlen(request->l_name) * 4 + 1);
126	strvis(vis_user, request->l_name, VIS_CSTYLE);
127	(void)snprintf(line_buf[i], N_CHARS,
128	    "talk: connection requested by %s@%s", vis_user, remote_machine);
129	sizes[i] = strlen(line_buf[i]);
130	max_size = max(max_size, sizes[i]);
131	i++;
132	(void)snprintf(line_buf[i], N_CHARS, "talk: respond with:  talk %s@%s",
133	    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	sizes[i] = strlen(line_buf[i]);
139	max_size = max(max_size, sizes[i]);
140	i++;
141	bptr = big_buf;
142	*bptr++ = '\007'; /* send something to wake them up */
143	*bptr++ = '\r';	/* add a \r in case of raw mode */
144	*bptr++ = '\n';
145	for (i = 0; i < N_LINES; i++) {
146		/* copy the line into the big buffer */
147		lptr = line_buf[i];
148		while (*lptr != '\0')
149			*(bptr++) = *(lptr++);
150		/* pad out the rest of the lines with blanks */
151		for (j = sizes[i]; j < max_size + 2; j++)
152			*(bptr++) = ' ';
153		*(bptr++) = '\r';	/* add a \r in case of raw mode */
154		*(bptr++) = '\n';
155	}
156	*bptr = '\0';
157	iovec.iov_base = big_buf;
158	iovec.iov_len = bptr - big_buf;
159	/*
160	 * we choose a timeout of RING_WAIT-5 seconds so that we don't
161	 * stack up processes trying to write messages to a tty
162	 * that is permanently blocked.
163	 */
164	if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
165		return (FAILED);
166
167	return (SUCCESS);
168}
169