rwall.c revision 21095 
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
36char 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/*static char sccsid[] = "from: @(#)wall.c	5.14 (Berkeley) 3/2/91";*/
43static char rcsid[] = "$Id: rwall.c,v 1.2 1995/05/30 06:33:30 rgrimes Exp $";
44#endif /* not lint */
45
46/*
47 * This program is not related to David Wall, whose Stanford Ph.D. thesis
48 * is entitled "Mechanisms for Broadcast and Selective Broadcast".
49 */
50
51#include <sys/param.h>
52#include <sys/stat.h>
53#include <sys/time.h>
54#include <sys/uio.h>
55#include <utmp.h>
56#include <pwd.h>
57#include <stdio.h>
58#include <stdlib.h>
59#include <paths.h>
60
61#include <rpc/rpc.h>
62#include <rpcsvc/rwall.h>
63
64int mbufsize;
65char *mbuf;
66
67/* ARGSUSED */
68main(argc, argv)
69	int argc;
70	char **argv;
71{
72	char *wallhost, res;
73	CLIENT *cl;
74	struct timeval tv;
75
76	if ((argc < 2) || (argc > 3)) {
77		fprintf(stderr, "usage: %s hostname [file]\n", argv[0]);
78		exit(1);
79	}
80
81	wallhost = argv[1];
82
83	makemsg(argv[2]);
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	tv.tv_sec = 15;		/* XXX ?? */
101	tv.tv_usec = 0;
102	if (clnt_call(cl, WALLPROC_WALL, xdr_wrapstring, &mbuf, xdr_void, &res, tv) != RPC_SUCCESS) {
103		/*
104		 * An error occurred while calling the server.
105		 * Print error message and die.
106		 */
107		clnt_perror(cl, wallhost);
108		exit(1);
109	}
110
111	exit(0);
112}
113
114makemsg(fname)
115	char *fname;
116{
117	register int ch, cnt;
118	struct tm *lt;
119	struct passwd *pw;
120	struct stat sbuf;
121	time_t now, time();
122	FILE *fp;
123	int fd;
124	char *p, *whom, hostname[MAXHOSTNAMELEN], lbuf[100], tmpname[15];
125	char *getlogin(), *strcpy(), *ttyname();
126
127	(void)strcpy(tmpname, _PATH_TMP);
128	(void)strcat(tmpname, "/wall.XXXXXX");
129	if (!(fd = mkstemp(tmpname)) || !(fp = fdopen(fd, "r+"))) {
130		(void)fprintf(stderr, "wall: can't open temporary file.\n");
131		exit(1);
132	}
133	(void)unlink(tmpname);
134
135	if (!(whom = getlogin()))
136		whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
137	(void)gethostname(hostname, sizeof(hostname));
138	(void)time(&now);
139	lt = localtime(&now);
140
141	/*
142	 * all this stuff is to blank out a square for the message;
143	 * we wrap message lines at column 79, not 80, because some
144	 * terminals wrap after 79, some do not, and we can't tell.
145	 * Which means that we may leave a non-blank character
146	 * in column 80, but that can't be helped.
147	 */
148	(void)fprintf(fp, "Remote Broadcast Message from %s@%s\n",
149	    whom, hostname);
150	(void)fprintf(fp, "        (%s) at %d:%02d ...\n", ttyname(2),
151	    lt->tm_hour, lt->tm_min);
152
153	putc('\n', fp);
154
155	if (fname && !(freopen(fname, "r", stdin))) {
156		(void)fprintf(stderr, "wall: can't read %s.\n", fname);
157		exit(1);
158	}
159	while (fgets(lbuf, sizeof(lbuf), stdin))
160		fputs(lbuf, fp);
161	rewind(fp);
162
163	if (fstat(fd, &sbuf)) {
164		(void)fprintf(stderr, "wall: can't stat temporary file.\n");
165		exit(1);
166	}
167	mbufsize = sbuf.st_size;
168	if (!(mbuf = malloc((u_int)mbufsize))) {
169		(void)fprintf(stderr, "wall: out of memory.\n");
170		exit(1);
171	}
172	if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize) {
173		(void)fprintf(stderr, "wall: can't read temporary file.\n");
174		exit(1);
175	}
176	(void)close(fd);
177}
178