wall.c revision 69231 
1/*
2 * Copyright (c) 1988, 1990, 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
34#ifndef lint
35static const char copyright[] =
36"@(#) Copyright (c) 1988, 1990, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39
40#ifndef lint
41#if 0
42static char sccsid[] = "@(#)wall.c	8.2 (Berkeley) 11/16/93";
43#endif
44static const char rcsid[] =
45  "$FreeBSD: head/usr.bin/wall/wall.c 69231 2000-11-26 22:36:35Z kris $";
46#endif /* not lint */
47
48/*
49 * This program is not related to David Wall, whose Stanford Ph.D. thesis
50 * is entitled "Mechanisms for Broadcast and Selective Broadcast".
51 */
52
53#include <sys/param.h>
54#include <sys/stat.h>
55#include <sys/uio.h>
56
57#include <ctype.h>
58#include <err.h>
59#include <locale.h>
60#include <paths.h>
61#include <pwd.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include <time.h>
66#include <unistd.h>
67#include <utmp.h>
68
69void	makemsg __P((char *));
70static void usage __P((void));
71char   *ttymsg __P((struct iovec *, int, char *, int));
72
73#define	IGNOREUSER	"sleeper"
74
75int nobanner;
76int mbufsize;
77char *mbuf;
78
79/* ARGSUSED */
80int
81main(argc, argv)
82	int argc;
83	char **argv;
84{
85	int ch;
86	struct iovec iov;
87	struct utmp utmp;
88	FILE *fp;
89	char *p;
90	char line[sizeof(utmp.ut_line) + 1];
91
92	(void)setlocale(LC_CTYPE, "");
93
94	while ((ch = getopt(argc, argv, "n")) != -1)
95		switch (ch) {
96		case 'n':
97			/* undoc option for shutdown: suppress banner */
98			if (geteuid() == 0)
99				nobanner = 1;
100			break;
101		case '?':
102		default:
103			usage();
104		}
105	argc -= optind;
106	argv += optind;
107	if (argc > 1)
108		usage();
109
110	makemsg(*argv);
111
112	if (!(fp = fopen(_PATH_UTMP, "r")))
113		err(1, "cannot read %s", _PATH_UTMP);
114	iov.iov_base = mbuf;
115	iov.iov_len = mbufsize;
116	/* NOSTRICT */
117	while (fread((char *)&utmp, sizeof(utmp), 1, fp) == 1) {
118		if (!utmp.ut_name[0] ||
119		    !strncmp(utmp.ut_name, IGNOREUSER, sizeof(utmp.ut_name)))
120			continue;
121		strncpy(line, utmp.ut_line, sizeof(utmp.ut_line));
122		line[sizeof(utmp.ut_line)] = '\0';
123		if ((p = ttymsg(&iov, 1, line, 60*5)) != NULL)
124			warnx("%s", p);
125	}
126	exit(0);
127}
128
129static void
130usage()
131{
132	(void)fprintf(stderr, "usage: wall [file]\n");
133	exit(1);
134}
135
136void
137makemsg(fname)
138	char *fname;
139{
140	register int cnt;
141	register unsigned char ch;
142	struct tm *lt;
143	struct passwd *pw;
144	struct stat sbuf;
145	time_t now;
146	FILE *fp;
147	int fd;
148	char *p, *tty, hostname[MAXHOSTNAMELEN], lbuf[256], tmpname[64];
149	const char *whom;
150
151	(void)snprintf(tmpname, sizeof(tmpname), "%s/wall.XXXXXX", _PATH_TMP);
152	if ((fd = mkstemp(tmpname)) == -1 || !(fp = fdopen(fd, "r+")))
153		err(1, "can't open temporary file");
154	(void)unlink(tmpname);
155
156	if (!nobanner) {
157		tty = ttyname(STDERR_FILENO);
158		if (tty == NULL)
159			tty = "no tty";
160
161		if (!(whom = getlogin()))
162			whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
163		(void)gethostname(hostname, sizeof(hostname));
164		(void)time(&now);
165		lt = localtime(&now);
166
167		/*
168		 * all this stuff is to blank out a square for the message;
169		 * we wrap message lines at column 79, not 80, because some
170		 * terminals wrap after 79, some do not, and we can't tell.
171		 * Which means that we may leave a non-blank character
172		 * in column 80, but that can't be helped.
173		 */
174		(void)fprintf(fp, "\r%79s\r\n", " ");
175		(void)snprintf(lbuf, sizeof(lbuf),
176		    "Broadcast Message from %s@%s",
177		    whom, hostname);
178		(void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf);
179		(void)snprintf(lbuf, sizeof(lbuf),
180		    "        (%s) at %d:%02d %s...", tty,
181		    lt->tm_hour, lt->tm_min, lt->tm_zone);
182		(void)fprintf(fp, "%-79.79s\r\n", lbuf);
183	}
184	(void)fprintf(fp, "%79s\r\n", " ");
185
186	if (fname && !(freopen(fname, "r", stdin)))
187		err(1, "can't read %s", fname);
188	while (fgets(lbuf, sizeof(lbuf), stdin))
189		for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
190			if (ch == '\r') {
191				cnt = 0;
192			} else if (cnt == 79 || ch == '\n') {
193				for (; cnt < 79; ++cnt)
194					putc(' ', fp);
195				putc('\r', fp);
196				putc('\n', fp);
197				cnt = 0;
198			} else if (((ch & 0x80) && ch < 0xA0) ||
199				   /* disable upper controls */
200				   (!isprint(ch) && !isspace(ch) &&
201				    ch != '\a' && ch != '\b')
202				  ) {
203				if (ch & 0x80) {
204					ch &= 0x7F;
205					putc('M', fp);
206					if (++cnt == 79) {
207						putc('\r', fp);
208						putc('\n', fp);
209						cnt = 0;
210					}
211					putc('-', fp);
212					if (++cnt == 79) {
213						putc('\r', fp);
214						putc('\n', fp);
215						cnt = 0;
216					}
217				}
218				if (iscntrl(ch)) {
219					ch ^= 040;
220					putc('^', fp);
221					if (++cnt == 79) {
222						putc('\r', fp);
223						putc('\n', fp);
224						cnt = 0;
225					}
226				}
227				putc(ch, fp);
228			} else {
229				putc(ch, fp);
230			}
231		}
232	(void)fprintf(fp, "%79s\r\n", " ");
233	rewind(fp);
234
235	if (fstat(fd, &sbuf))
236		err(1, "can't stat temporary file");
237	mbufsize = sbuf.st_size;
238	if (!(mbuf = malloc((u_int)mbufsize)))
239		err(1, "out of memory");
240	if (fread(mbuf, sizeof(*mbuf), mbufsize, fp) != mbufsize)
241		err(1, "can't read temporary file");
242	(void)close(fd);
243}
244