xref: /dragonfly/usr.bin/rwall/rwall.c (revision cab8bf9b)
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. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * @(#) Copyright (c) 1988 Regents of the University of California. All rights reserved.
31  * @(#)wall.c	5.14 (Berkeley) 3/2/91
32  * $FreeBSD: src/usr.bin/rwall/rwall.c,v 1.14 2005/05/21 09:55:08 ru Exp $
33  * $DragonFly: src/usr.bin/rwall/rwall.c,v 1.7 2005/07/30 16:44:12 liamfoy Exp $
34  */
35 
36 /*
37  * This program is not related to David Wall, whose Stanford Ph.D. thesis
38  * is entitled "Mechanisms for Broadcast and Selective Broadcast".
39  */
40 
41 #include <sys/types.h>
42 #include <sys/param.h>
43 #include <sys/stat.h>
44 
45 #include <err.h>
46 #include <paths.h>
47 #include <pwd.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <time.h>
51 #include <unistd.h>
52 
53 #include <rpc/rpc.h>
54 #include <rpcsvc/rwall.h>
55 
56 static char	*mbuf;
57 
58 static void	makemsg(const char *);
59 static void	usage(void);
60 
61 int
62 main(int argc, char **argv)
63 {
64 	const char *wallhost;
65 	char *res;
66 	CLIENT *cl;
67 	struct timeval tv;
68 	int c;
69 
70 	while ((c = getopt(argc, argv, "")) != -1) {
71 		switch (c) {
72 		default:
73 			usage();
74 		}
75 	}
76 
77 	argc -= optind;
78 	argv += optind;
79 
80 	if (argc < 1 || argc > 2)
81 		usage();
82 
83 	wallhost = argv[0];
84 
85 	/*
86 	 * Create client "handle" used for calling MESSAGEPROG on the
87 	 * server designated on the command line. We tell the rpc package
88 	 * to use the "tcp" protocol when contacting the server.
89 	*/
90 	cl = clnt_create(wallhost, WALLPROG, WALLVERS, "udp");
91 	if (cl == NULL) {
92 		/*
93 		 * Couldn't establish connection with server.
94 		 * Print error message and die.
95 		 */
96 		clnt_pcreateerror(wallhost);
97 		exit(1);
98 	}
99 
100 	makemsg(argv[1]);
101 
102 	tv.tv_sec = 15;		/* XXX ?? */
103 	tv.tv_usec = 0;
104 	if (clnt_call(cl, WALLPROC_WALL, (xdrproc_t)xdr_wrapstring, &mbuf,
105 	    (xdrproc_t)xdr_void, &res, tv) != RPC_SUCCESS) {
106 		/*
107 		 * An error occurred while calling the server.
108 		 * Print error message and die.
109 		 */
110 		clnt_perror(cl, wallhost);
111 		exit(1);
112 	}
113 
114 	return(0);
115 }
116 
117 static void
118 usage(void)
119 {
120 	fprintf(stderr, "usage: rwall host [file]\n");
121 	exit(1);
122 }
123 
124 static void
125 makemsg(const char *fname)
126 {
127 	struct tm *lt;
128 	struct passwd *pw;
129 	struct stat sbuf;
130 	time_t now;
131 	FILE *fp;
132 	int fd;
133 	size_t mbufsize;
134 	char hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[MAXPATHLEN];
135 	const char *whom, *tty;
136 
137 	snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP);
138 	if ((fd = mkstemp(tmpname)) == -1 || (fp = fdopen(fd, "r+")) == NULL)
139 		err(1, "can't open temporary file");
140 
141 	if (unlink(tmpname) == -1)
142 		err(1, "unlink failed: %s", tmpname);
143 
144 	if ((whom = getlogin()) == NULL)
145 		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
146 	gethostname(hostname, sizeof(hostname));
147 
148 	time(&now);
149 	lt = localtime(&now);
150 
151 	/*
152 	 * all this stuff is to blank out a square for the message;
153 	 * we wrap message lines at column 79, not 80, because some
154 	 * terminals wrap after 79, some do not, and we can't tell.
155 	 * Which means that we may leave a non-blank character
156 	 * in column 80, but that can't be helped.
157 	 */
158 	fprintf(fp, "Remote Broadcast Message from %s@%s\n", whom, hostname);
159 	tty = ttyname(STDERR_FILENO);
160 	if (tty == NULL)
161 		tty = "notty";
162 	fprintf(fp, "        (%s) at %d:%02d ...\n", tty,
163 		lt->tm_hour, lt->tm_min);
164 
165 	putc('\n', fp);
166 
167 	if (fname && !(freopen(fname, "r", stdin)))
168 		err(1, "can't read %s", fname);
169 	while (fgets(lbuf, sizeof(lbuf), stdin))
170 		fputs(lbuf, fp);
171 	rewind(fp);
172 
173 	if (fstat(fd, &sbuf))
174 		err(1, "can't stat temporary file");
175 	mbufsize = (size_t)sbuf.st_size;
176 	if ((mbuf = malloc(mbufsize)) == NULL)
177 		err(1, "malloc failed");
178 	if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != (u_int)mbufsize)
179 		err(1, "can't read temporary file");
180 	if (close(fd))
181 		warn("close failed");
182 }
183