xref: /original-bsd/libexec/talkd/announce.c (revision 0842ddeb)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)announce.c	8.3 (Berkeley) 04/28/95";
10 #endif /* not lint */
11 
12 #include <sys/types.h>
13 #include <sys/uio.h>
14 #include <sys/stat.h>
15 #include <sys/time.h>
16 #include <sys/wait.h>
17 #include <sys/socket.h>
18 #include <protocols/talkd.h>
19 #include <sgtty.h>
20 #include <errno.h>
21 #include <syslog.h>
22 #include <unistd.h>
23 #include <stdio.h>
24 #include <string.h>
25 #include <vis.h>
26 #include <paths.h>
27 
28 extern char hostname[];
29 
30 /*
31  * Announce an invitation to talk.
32  */
33 
34 /*
35  * See if the user is accepting messages. If so, announce that
36  * a talk is requested.
37  */
38 announce(request, remote_machine)
39 	CTL_MSG *request;
40 	char *remote_machine;
41 {
42 	char full_tty[32];
43 	FILE *tf;
44 	struct stat stbuf;
45 
46 	(void)snprintf(full_tty, sizeof(full_tty),
47 	    "%s%s", _PATH_DEV, request->r_tty);
48 	if (stat(full_tty, &stbuf) < 0 || (stbuf.st_mode&020) == 0)
49 		return (PERMISSION_DENIED);
50 	return (print_mesg(request->r_tty, tf, request, remote_machine));
51 }
52 
53 #define max(a,b) ( (a) > (b) ? (a) : (b) )
54 #define N_LINES 5
55 #define N_CHARS 256
56 
57 /*
58  * Build a block of characters containing the message.
59  * It is sent blank filled and in a single block to
60  * try to keep the message in one piece if the recipient
61  * in in vi at the time
62  */
63 print_mesg(tty, tf, request, remote_machine)
64 	char *tty;
65 	FILE *tf;
66 	CTL_MSG *request;
67 	char *remote_machine;
68 {
69 	struct timeval clock;
70 	struct timezone zone;
71 	struct tm *localtime();
72 	struct tm *localclock;
73 	struct iovec iovec;
74 	char line_buf[N_LINES][N_CHARS];
75 	int sizes[N_LINES];
76 	char big_buf[N_LINES*N_CHARS];
77 	char *bptr, *lptr, *vis_user;
78 	int i, j, max_size;
79 
80 	i = 0;
81 	max_size = 0;
82 	gettimeofday(&clock, &zone);
83 	localclock = localtime( &clock.tv_sec );
84 	(void)sprintf(line_buf[i], " ");
85 	sizes[i] = strlen(line_buf[i]);
86 	max_size = max(max_size, sizes[i]);
87 	i++;
88 	(void)sprintf(line_buf[i], "Message from Talk_Daemon@%s at %d:%02d ...",
89 	hostname, localclock->tm_hour , localclock->tm_min );
90 	sizes[i] = strlen(line_buf[i]);
91 	max_size = max(max_size, sizes[i]);
92 	i++;
93 	vis_user = (char *) malloc(strlen(request->l_name) * 4 + 1);
94 	strvis(vis_user, request->l_name, VIS_CSTYLE);
95 	(void)sprintf(line_buf[i], "talk: connection requested by %s@%s",
96 		vis_user, remote_machine);
97 	sizes[i] = strlen(line_buf[i]);
98 	max_size = max(max_size, sizes[i]);
99 	i++;
100 	(void)sprintf(line_buf[i], "talk: respond with:  talk %s@%s",
101 		vis_user, remote_machine);
102 	sizes[i] = strlen(line_buf[i]);
103 	max_size = max(max_size, sizes[i]);
104 	i++;
105 	(void)sprintf(line_buf[i], " ");
106 	sizes[i] = strlen(line_buf[i]);
107 	max_size = max(max_size, sizes[i]);
108 	i++;
109 	bptr = big_buf;
110 	*bptr++ = ''; /* send something to wake them up */
111 	*bptr++ = '\r';	/* add a \r in case of raw mode */
112 	*bptr++ = '\n';
113 	for (i = 0; i < N_LINES; i++) {
114 		/* copy the line into the big buffer */
115 		lptr = line_buf[i];
116 		while (*lptr != '\0')
117 			*(bptr++) = *(lptr++);
118 		/* pad out the rest of the lines with blanks */
119 		for (j = sizes[i]; j < max_size + 2; j++)
120 			*(bptr++) = ' ';
121 		*(bptr++) = '\r';	/* add a \r in case of raw mode */
122 		*(bptr++) = '\n';
123 	}
124 	*bptr = '\0';
125 	iovec.iov_base = big_buf;
126 	iovec.iov_len = bptr - big_buf;
127 	/*
128 	 * we choose a timeout of RING_WAIT-5 seconds so that we don't
129 	 * stack up processes trying to write messages to a tty
130 	 * that is permanently blocked.
131 	 */
132 	if (ttymsg(&iovec, 1, tty, RING_WAIT - 5) != NULL)
133 		return (FAILED);
134 
135 	return (SUCCESS);
136 }
137