freebsd-dev/usr.sbin/ypserv/yp_main.c
Bill Paul eb822b5612 Add some tweaks to hopefully fix a problem I've started to notice recently.
Under certain conditions (possibly associated with heavy load), ypserv will
fork() child processes that don't exit like they're supposed to. I think
this is because of some suspect logic in the ypproc_all procedure. I updated
it to use what I hope is a more bulletproof approach.

Also tweaked yp_svc_run() a little so that the 'are we a child?' test happens
at every pass through the for(;;) loop, not just immediately after returning
from svc_getreqset2().
1999-02-10 16:16:14 +00:00

338 lines
7.8 KiB
C

/*
* Copyright (c) 1995
* Bill Paul <wpaul@ctr.columbia.edu>. 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 Bill Paul.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY Bill Paul 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 Bill Paul 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 rcsid[] =
"$Id: yp_main.c,v 1.18 1998/06/04 15:11:14 wpaul Exp $";
#endif /* not lint */
/*
* ypserv startup function.
* We need out own main() since we have to do some additional work
* that rpcgen won't do for us. Most of this file was generated using
* rpcgen.new, and later modified.
*/
#include "yp.h"
#include <err.h>
#include <errno.h>
#include <memory.h>
#include <stdio.h>
#include <signal.h>
#include <stdlib.h> /* getenv, exit */
#include <string.h> /* strcmp */
#include <syslog.h>
#include <unistd.h>
#include <rpc/pmap_clnt.h> /* for pmap_unset */
#include <sys/ttycom.h> /* TIOCNOTTY */
#ifdef __cplusplus
#include <sysent.h> /* getdtablesize, open */
#endif /* __cplusplus */
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/wait.h>
#include "yp_extern.h"
#include <rpc/rpc.h>
#ifndef SIG_PF
#define SIG_PF void(*)(int)
#endif
#define _RPCSVC_CLOSEDOWN 120
int _rpcpmstart; /* Started by a port monitor ? */
static int _rpcfdtype;
/* Whether Stream or Datagram ? */
/* States a server can be in wrt request */
#define _IDLE 0
#define _SERVED 1
#define _SERVING 2
extern void ypprog_1 __P((struct svc_req *, register SVCXPRT *));
extern void ypprog_2 __P((struct svc_req *, register SVCXPRT *));
extern int _rpc_dtablesize __P((void));
extern int _rpcsvcstate; /* Set when a request is serviced */
char *progname = "ypserv";
char *yp_dir = _PATH_YP;
/*int debug = 0;*/
int do_dns = 0;
int resfd;
static
void _msgout(char* msg)
{
if (debug) {
if (_rpcpmstart)
syslog(LOG_ERR, msg);
else
warnx("%s", msg);
} else
syslog(LOG_ERR, msg);
}
static void
yp_svc_run()
{
#ifdef FD_SETSIZE
fd_set readfds;
#else
int readfds;
#endif /* def FD_SETSIZE */
extern int forked;
int pid;
int fd_setsize = _rpc_dtablesize();
struct timeval timeout;
/* Establish the identity of the parent ypserv process. */
pid = getpid();
for (;;) {
#ifdef FD_SETSIZE
readfds = svc_fdset;
#else
readfds = svc_fds;
#endif /* def FD_SETSIZE */
FD_SET(resfd, &readfds);
timeout.tv_sec = RESOLVER_TIMEOUT;
timeout.tv_usec = 0;
switch (select(fd_setsize, &readfds, NULL, NULL,
&timeout)) {
case -1:
if (errno == EINTR) {
continue;
}
warn("svc_run: - select failed");
return;
case 0:
yp_prune_dnsq();
break;
default:
if (FD_ISSET(resfd, &readfds)) {
yp_run_dnsq();
FD_CLR(resfd, &readfds);
}
svc_getreqset(&readfds);
}
if (forked && pid != getpid())
_exit(0);
}
}
static void unregister()
{
(void) pmap_unset(YPPROG, YPVERS);
(void) pmap_unset(YPPROG, YPOLDVERS);
}
static void reaper(sig)
int sig;
{
int status;
int saved_errno;
saved_errno = errno;
if (sig == SIGHUP) {
load_securenets();
#ifdef DB_CACHE
yp_flush_all();
#endif
errno = saved_errno;
return;
}
if (sig == SIGCHLD) {
while (wait3(&status, WNOHANG, NULL) > 0)
children--;
} else {
unregister();
exit(0);
}
errno = saved_errno;
return;
}
static void usage()
{
fprintf(stderr, "usage: ypserv [-h] [-d] [-n] [-p path]\n");
exit(1);
}
static void
closedown(int sig)
{
if (_rpcsvcstate == _IDLE) {
extern fd_set svc_fdset;
static int size;
int i, openfd;
if (_rpcfdtype == SOCK_DGRAM) {
unregister();
exit(0);
}
if (size == 0) {
size = getdtablesize();
}
for (i = 0, openfd = 0; i < size && openfd < 2; i++)
if (FD_ISSET(i, &svc_fdset))
openfd++;
if (openfd <= 1) {
unregister();
exit(0);
}
}
if (_rpcsvcstate == _SERVED)
_rpcsvcstate = _IDLE;
(void) signal(SIGALRM, (SIG_PF) closedown);
(void) alarm(_RPCSVC_CLOSEDOWN/2);
}
int
main(argc, argv)
int argc;
char *argv[];
{
register SVCXPRT *transp = NULL;
int sock;
int proto = 0;
struct sockaddr_in saddr;
int asize = sizeof (saddr);
int ch;
while ((ch = getopt(argc, argv, "hdnp:")) != -1) {
switch(ch) {
case 'd':
debug = ypdb_debug = 1;
break;
case 'n':
do_dns = 1;
break;
case 'p':
yp_dir = optarg;
break;
case 'h':
default:
usage();
}
}
load_securenets();
yp_init_resolver();
#ifdef DB_CACHE
yp_init_dbs();
#endif
if (getsockname(0, (struct sockaddr *)&saddr, &asize) == 0) {
int ssize = sizeof (int);
if (saddr.sin_family != AF_INET)
exit(1);
if (getsockopt(0, SOL_SOCKET, SO_TYPE,
(char *)&_rpcfdtype, &ssize) == -1)
exit(1);
sock = 0;
_rpcpmstart = 1;
proto = 0;
openlog("ypserv", LOG_PID, LOG_DAEMON);
} else {
if (!debug) {
if (daemon(0,0)) {
err(1,"cannot fork");
}
openlog("ypserv", LOG_PID, LOG_DAEMON);
}
sock = RPC_ANYSOCK;
(void) pmap_unset(YPPROG, YPVERS);
(void) pmap_unset(YPPROG, 1);
}
if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_DGRAM)) {
transp = svcudp_create(sock);
if (transp == NULL) {
_msgout("cannot create udp service");
exit(1);
}
if (!_rpcpmstart)
proto = IPPROTO_UDP;
if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
_msgout("unable to register (YPPROG, YPOLDVERS, udp)");
exit(1);
}
if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
_msgout("unable to register (YPPROG, YPVERS, udp)");
exit(1);
}
}
if ((_rpcfdtype == 0) || (_rpcfdtype == SOCK_STREAM)) {
transp = svctcp_create(sock, 0, 0);
if (transp == NULL) {
_msgout("cannot create tcp service");
exit(1);
}
if (!_rpcpmstart)
proto = IPPROTO_TCP;
if (!svc_register(transp, YPPROG, YPOLDVERS, ypprog_1, proto)) {
_msgout("unable to register (YPPROG, YPOLDVERS, tcp)");
exit(1);
}
if (!svc_register(transp, YPPROG, YPVERS, ypprog_2, proto)) {
_msgout("unable to register (YPPROG, YPVERS, tcp)");
exit(1);
}
}
if (transp == (SVCXPRT *)NULL) {
_msgout("could not create a handle");
exit(1);
}
if (_rpcpmstart) {
(void) signal(SIGALRM, (SIG_PF) closedown);
(void) alarm(_RPCSVC_CLOSEDOWN/2);
}
/*
* Make sure SIGPIPE doesn't blow us away while servicing TCP
* connections.
*/
(void) signal(SIGPIPE, SIG_IGN);
(void) signal(SIGCHLD, (SIG_PF) reaper);
(void) signal(SIGTERM, (SIG_PF) reaper);
(void) signal(SIGINT, (SIG_PF) reaper);
(void) signal(SIGHUP, (SIG_PF) reaper);
yp_svc_run();
_msgout("svc_run returned");
exit(1);
/* NOTREACHED */
}