xref: /freebsd/usr.bin/rwall/rwall.c (revision 1b6c76a2fe091c74f08427e6c870851025a9cf67)
1 /*
2  * Copyright (c) 1993 Christopher G. Demetriou
3  * Copyright (c) 1988, 1990 Regents of the University of California.
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. All advertising materials mentioning features or use of this software
15  *    must display the following acknowledgement:
16  *	This product includes software developed by the University of
17  *	California, Berkeley and its contributors.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef lint
36 static const char copyright[] =
37 "@(#) Copyright (c) 1988 Regents of the University of California.\n\
38  All rights reserved.\n";
39 #endif /* not lint */
40 
41 #ifndef lint
42 #if 0
43 static char sccsid[] = "from: @(#)wall.c	5.14 (Berkeley) 3/2/91";
44 #endif
45 static const char rcsid[] =
46   "$FreeBSD$";
47 #endif /* not lint */
48 
49 /*
50  * This program is not related to David Wall, whose Stanford Ph.D. thesis
51  * is entitled "Mechanisms for Broadcast and Selective Broadcast".
52  */
53 
54 #include <sys/param.h>
55 #include <sys/stat.h>
56 #include <sys/time.h>
57 #include <sys/uio.h>
58 #include <err.h>
59 #include <paths.h>
60 #include <pwd.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <time.h>
65 #include <unistd.h>
66 #include <utmp.h>
67 
68 #include <rpc/rpc.h>
69 #include <rpcsvc/rwall.h>
70 
71 int mbufsize;
72 char *mbuf;
73 
74 void	makemsg __P((char *));
75 static void usage __P((void));
76 char   *ttymsg __P((struct iovec *, int, char *, int));
77 
78 /* ARGSUSED */
79 int
80 main(argc, argv)
81 	int argc;
82 	char **argv;
83 {
84 	char *wallhost, res;
85 	CLIENT *cl;
86 	struct timeval tv;
87 
88 	if ((argc < 2) || (argc > 3))
89 		usage();
90 
91 	wallhost = argv[1];
92 
93 	makemsg(argv[2]);
94 
95 	/*
96 	 * Create client "handle" used for calling MESSAGEPROG on the
97 	 * server designated on the command line. We tell the rpc package
98 	 * to use the "tcp" protocol when contacting the server.
99 	*/
100 	cl = clnt_create(wallhost, WALLPROG, WALLVERS, "udp");
101 	if (cl == NULL) {
102 		/*
103 		 * Couldn't establish connection with server.
104 		 * Print error message and die.
105 		 */
106 		errx(1, "%s", clnt_spcreateerror(wallhost));
107 	}
108 
109 	tv.tv_sec = 15;		/* XXX ?? */
110 	tv.tv_usec = 0;
111 	if (clnt_call(cl, WALLPROC_WALL, xdr_wrapstring, &mbuf, xdr_void, &res, tv) != RPC_SUCCESS) {
112 		/*
113 		 * An error occurred while calling the server.
114 		 * Print error message and die.
115 		 */
116 		errx(1, "%s", clnt_sperror(cl, wallhost));
117 	}
118 
119 	exit(0);
120 }
121 
122 static void
123 usage()
124 {
125 	(void)fprintf(stderr, "usage: rwall hostname [file]\n");
126 	exit(1);
127 }
128 
129 void
130 makemsg(fname)
131 	char *fname;
132 {
133 	struct tm *lt;
134 	struct passwd *pw;
135 	struct stat sbuf;
136 	time_t now;
137 	FILE *fp;
138 	int fd;
139 	char *tty, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64];
140 	const char *whom;
141 
142 	(void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP);
143 	if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+")))
144 		err(1, "can't open temporary file");
145 	(void)unlink(tmpname);
146 
147 	if (!(whom = getlogin()))
148 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
149 	(void)gethostname(hostname, sizeof(hostname));
150 	(void)time(&now);
151 	lt = localtime(&now);
152 
153 	/*
154 	 * all this stuff is to blank out a square for the message;
155 	 * we wrap message lines at column 79, not 80, because some
156 	 * terminals wrap after 79, some do not, and we can't tell.
157 	 * Which means that we may leave a non-blank character
158 	 * in column 80, but that can't be helped.
159 	 */
160 	(void)fprintf(fp, "Remote Broadcast Message from %s@%s\n",
161 	    whom, hostname);
162 	tty = ttyname(STDERR_FILENO);
163 	if (tty == NULL)
164 		tty = "no tty";
165 	(void)fprintf(fp, "        (%s) at %d:%02d ...\n", tty,
166 	    lt->tm_hour, lt->tm_min);
167 
168 	putc('\n', fp);
169 
170 	if (fname && !(freopen(fname, "r", stdin)))
171 		err(1, "can't read %s", fname);
172 	while (fgets(lbuf, sizeof(lbuf), stdin))
173 		fputs(lbuf, fp);
174 	rewind(fp);
175 
176 	if (fstat(fd, &sbuf))
177 		err(1, "can't stat temporary file");
178 	mbufsize = sbuf.st_size;
179 	if (!(mbuf = malloc((u_int)mbufsize)))
180 		err(1, "out of memory");
181 	if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
182 		err(1, "can't read temporary file");
183 	(void)close(fd);
184 }
185