freebsd-skq/libexec/talkd/talkd.c
Kris Kennaway 5007eafa5e Save errno in signal handler
Obtained from:	OpenBSD
MFC After:	1 week
2001-07-24 05:41:13 +00:00

142 lines
4.1 KiB
C

/*
* Copyright (c) 1983, 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*/
#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 1983, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)talkd.c 8.1 (Berkeley) 6/4/93";
#endif
static const char rcsid[] =
"$FreeBSD$";
#endif /* not lint */
/*
* The top level of the daemon, the format is heavily borrowed
* from rwhod.c. Basically: find out who and where you are;
* disconnect all descriptors and ttys, and then endless
* loop on waiting for and processing requests
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <protocols/talkd.h>
#include <err.h>
#include <errno.h>
#include <paths.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
CTL_MSG request;
CTL_RESPONSE response;
int sockt;
int debug = 0;
long lastmsgtime;
char hostname[MAXHOSTNAMELEN];
#define TIMEOUT 30
#define MAXIDLE 120
void process_request __P((CTL_MSG *, CTL_RESPONSE *));
void timeout();
int
main(argc, argv)
int argc;
char *argv[];
{
register CTL_MSG *mp = &request;
int cc;
#ifdef NOTDEF
/*
* removed so ntalkd can run in tty sandbox
*/
if (getuid())
errx(1, "getuid: not super-user");
#endif
openlog("talkd", LOG_PID, LOG_DAEMON);
if (gethostname(hostname, sizeof(hostname) - 1) < 0) {
syslog(LOG_ERR, "gethostname: %m");
_exit(1);
}
hostname[sizeof(hostname) - 1] = '\0';
if (chdir(_PATH_DEV) < 0) {
syslog(LOG_ERR, "chdir: %s: %m", _PATH_DEV);
_exit(1);
}
if (argc > 1 && strcmp(argv[1], "-d") == 0)
debug = 1;
signal(SIGALRM, timeout);
alarm(TIMEOUT);
for (;;) {
cc = recv(0, (char *)mp, sizeof (*mp), 0);
if (cc != sizeof (*mp)) {
if (cc < 0 && errno != EINTR)
syslog(LOG_WARNING, "recv: %m");
continue;
}
lastmsgtime = time(0);
process_request(mp, &response);
/* can block here, is this what I want? */
mp->ctl_addr.sa_family = htons(mp->ctl_addr.sa_family);
cc = sendto(sockt, (char *)&response,
sizeof (response), 0, (struct sockaddr *)&mp->ctl_addr,
sizeof (mp->ctl_addr));
if (cc != sizeof (response))
syslog(LOG_WARNING, "sendto: %m");
}
}
void
timeout()
{
int save_errno = errno;
if (time(0) - lastmsgtime >= MAXIDLE)
_exit(0);
alarm(TIMEOUT);
errno = save_errno;
}