NetBSD-5.0.2/usr.bin/wall/wall.c
/* $NetBSD: wall.c,v 1.26 2008/07/21 14:19:27 lukem Exp $ */
/*
* Copyright (c) 1988, 1990, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1988, 1990, 1993\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)wall.c 8.2 (Berkeley) 11/16/93";
#endif
__RCSID("$NetBSD: wall.c,v 1.26 2008/07/21 14:19:27 lukem Exp $");
#endif /* not lint */
/*
* This program is not related to David Wall, whose Stanford Ph.D. thesis
* is entitled "Mechanisms for Broadcast and Selective Broadcast".
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/uio.h>
#include <err.h>
#include <grp.h>
#include <errno.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>
#include "utmpentry.h"
#include "term_chk.h"
void addgroup(char *);
void makemsg(const char *);
int main(int, char **);
void usage(void);
struct wallgroup {
gid_t gid;
char *name;
char **mem;
struct wallgroup *next;
} *grouplist;
int nobanner;
size_t mbufsize;
char *mbuf;
/* ARGSUSED */
int
main(int argc, char **argv)
{
int ch;
struct iovec iov;
char *p, **mem;
struct utmpentry *ep;
gid_t egid;
struct wallgroup *wg;
struct passwd *pw;
setprogname(argv[0]);
egid = getegid();
if (setegid(getgid()) == -1)
err(1, "setegid");
pw = getpwnam("nobody");
(void)check_sender(NULL, getuid(), egid);
while ((ch = getopt(argc, argv, "g:n")) != -1)
switch (ch) {
case 'n':
/* undoc option for shutdown: suppress banner */
if (geteuid() == 0 || (pw && getuid() == pw->pw_uid))
nobanner = 1;
break;
case 'g':
addgroup(optarg);
break;
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc > 1)
usage();
makemsg(*argv);
iov.iov_base = mbuf;
iov.iov_len = mbufsize;
(void)getutentries(NULL, &ep);
(void)setegid(egid);
for (; ep; ep = ep->next) {
if (grouplist) {
int ingroup;
ingroup = 0;
pw = getpwnam(ep->name);
if (!pw)
continue;
for (wg = grouplist; wg && !ingroup; wg = wg->next) {
if (wg->gid == pw->pw_gid)
ingroup = 1;
for (mem = wg->mem; *mem && !ingroup; mem++)
if (strcmp(ep->name, *mem) == 0)
ingroup = 1;
}
if (ingroup == 0)
continue;
}
if ((p = ttymsg(&iov, 1, ep->line, 60*5)) != NULL)
warnx("%s", p);
}
exit(0);
}
void
addgroup(char *name)
{
int i;
struct group *grp;
struct wallgroup *g;
grp = getgrnam(name);
if ((grp = getgrnam(name)) == NULL)
errx(1, "unknown group `%s'", name);
for (i = 0; grp->gr_mem[i]; i++)
continue;
g = (struct wallgroup *)malloc(sizeof *g);
if (g == NULL)
err(1, "malloc");
g->gid = grp->gr_gid;
g->name = name;
g->mem = (char **)malloc(i + 1);
if (g->mem == NULL)
err(1, "malloc");
for (i = 0; grp->gr_mem[i] != NULL; i++) {
g->mem[i] = strdup(grp->gr_mem[i]);
if (g->mem[i] == NULL)
err(1, "malloc");
}
g->mem[i] = NULL;
g->next = grouplist;
grouplist = g;
}
void
makemsg(const char *fname)
{
int ch, cnt;
struct tm *lt;
struct passwd *pw;
struct stat sbuf;
time_t now;
FILE *fp;
int fd;
const char *whom;
char *p, *tty, tmpname[MAXPATHLEN], lbuf[100],
hostname[MAXHOSTNAMELEN+1];
(void)snprintf(tmpname, sizeof tmpname, "%s/wall.XXXXXX", _PATH_TMP);
if ((fd = mkstemp(tmpname)) == -1)
err(1, "can't open temporary file");
(void)unlink(tmpname);
if (!(fp = fdopen(fd, "r+")))
err(1, "can't open temporary file");
if (!nobanner) {
if (!(whom = getlogin()))
whom = (pw = getpwuid(getuid())) ? pw->pw_name : "???";
(void)gethostname(hostname, sizeof(hostname));
hostname[sizeof(hostname) - 1] = '\0';
(void)time(&now);
lt = localtime(&now);
/*
* all this stuff is to blank out a square for the message;
* we wrap message lines at column 79, not 80, because some
* terminals wrap after 79, some do not, and we can't tell.
* Which means that we may leave a non-blank character
* in column 80, but that can't be helped.
*/
(void)fprintf(fp, "\r%79s\r\n", " ");
(void)snprintf(lbuf, sizeof lbuf,
"Broadcast Message from %s@%s", whom, hostname);
(void)fprintf(fp, "%-79.79s\007\007\r\n", lbuf);
tty = ttyname(STDERR_FILENO);
if (tty == NULL)
tty = "??";
(void)snprintf(lbuf, sizeof lbuf,
" (%s) at %d:%02d %s...", tty,
lt->tm_hour, lt->tm_min, lt->tm_zone);
(void)fprintf(fp, "%-79.79s\r\n", lbuf);
}
(void)fprintf(fp, "%79s\r\n", " ");
if (fname && !(freopen(fname, "r", stdin)))
err(1, "can't read %s", fname);
while (fgets(lbuf, sizeof(lbuf), stdin))
for (cnt = 0, p = lbuf; (ch = *p) != '\0'; ++p, ++cnt) {
if (cnt == 79 || ch == '\n') {
for (; cnt < 79; ++cnt)
putc(' ', fp);
putc('\r', fp);
putc('\n', fp);
cnt = -1;
}
if (ch != '\n')
putc(ch, fp);
}
(void)fprintf(fp, "%79s\r\n", " ");
rewind(fp);
if (fstat(fd, &sbuf))
err(1, "can't stat temporary file");
if (sbuf.st_size > SIZE_T_MAX)
errx(1, "file too big");
mbufsize = sbuf.st_size;
if (!(mbuf = malloc(mbufsize)))
err(1, "malloc");
if (fread(mbuf, 1, mbufsize, fp) != mbufsize)
err(1, "can't read temporary file");
(void)fclose(fp);
}
void
usage(void)
{
(void)fprintf(stderr, "usage: %s [-g group] [file]\n", getprogname());
exit(1);
}