| Current Path : /usr/src/lib/libc/net/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/lib/libc/net/gethostbydns.c |
/*
* ++Copyright++ 1985, 1988, 1993
* -
* Copyright (c) 1985, 1988, 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.
* 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.
* -
* Portions Copyright (c) 1993 by Digital Equipment Corporation.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies, and that
* the name of Digital Equipment Corporation not be used in advertising or
* publicity pertaining to distribution of the document or software without
* specific, written prior permission.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND DIGITAL EQUIPMENT CORP. DISCLAIMS ALL
* WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL DIGITAL EQUIPMENT
* CORPORATION BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
* DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
* PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
* ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
* SOFTWARE.
* -
* --Copyright--
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)gethostnamadr.c 8.1 (Berkeley) 6/4/93";
static char fromrcsid[] = "From: Id: gethnamaddr.c,v 8.23 1998/04/07 04:59:46 vixie Exp $";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/lib/libc/net/gethostbydns.c 211340 2010-08-15 16:28:08Z ume $");
#include <sys/types.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <netdb.h>
#include <resolv.h>
#include <ctype.h>
#include <errno.h>
#include <syslog.h>
#include <stdarg.h>
#include <nsswitch.h>
#include "netdb_private.h"
#include "res_config.h"
#define SPRINTF(x) ((size_t)sprintf x)
static const char AskedForGot[] =
"gethostby*.gethostanswer: asked for \"%s\", got \"%s\"";
#ifdef RESOLVSORT
static void addrsort(char **, int, res_state);
#endif
#ifdef DEBUG
static void dprintf(char *, int, res_state) __printflike(1, 0);
#endif
#define MAXPACKET (64*1024)
typedef union {
HEADER hdr;
u_char buf[MAXPACKET];
} querybuf;
typedef union {
int32_t al;
char ac;
} align;
int _dns_ttl_;
#ifdef DEBUG
static void
dprintf(msg, num, res)
char *msg;
int num;
res_state res;
{
if (res->options & RES_DEBUG) {
int save = errno;
printf(msg, num);
errno = save;
}
}
#else
# define dprintf(msg, num, res) /*nada*/
#endif
#define BOUNDED_INCR(x) \
do { \
cp += x; \
if (cp > eom) { \
RES_SET_H_ERRNO(statp, NO_RECOVERY); \
return (-1); \
} \
} while (0)
#define BOUNDS_CHECK(ptr, count) \
do { \
if ((ptr) + (count) > eom) { \
RES_SET_H_ERRNO(statp, NO_RECOVERY); \
return (-1); \
} \
} while (0)
static int
gethostanswer(const querybuf *answer, int anslen, const char *qname, int qtype,
struct hostent *he, struct hostent_data *hed, res_state statp)
{
const HEADER *hp;
const u_char *cp;
int n;
const u_char *eom, *erdata;
char *bp, *ep, **ap, **hap;
int type, class, ancount, qdcount;
int haveanswer, had_error;
int toobig = 0;
char tbuf[MAXDNAME];
const char *tname;
int (*name_ok)(const char *);
tname = qname;
he->h_name = NULL;
eom = answer->buf + anslen;
switch (qtype) {
case T_A:
case T_AAAA:
name_ok = res_hnok;
break;
case T_PTR:
name_ok = res_dnok;
break;
default:
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1); /* XXX should be abort(); */
}
/*
* find first satisfactory answer
*/
hp = &answer->hdr;
ancount = ntohs(hp->ancount);
qdcount = ntohs(hp->qdcount);
bp = hed->hostbuf;
ep = hed->hostbuf + sizeof hed->hostbuf;
cp = answer->buf;
BOUNDED_INCR(HFIXEDSZ);
if (qdcount != 1) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
if ((n < 0) || !(*name_ok)(bp)) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
BOUNDED_INCR(n + QFIXEDSZ);
if (qtype == T_A || qtype == T_AAAA) {
/* res_send() has already verified that the query name is the
* same as the one we sent; this just gets the expanded name
* (i.e., with the succeeding search-domain tacked on).
*/
n = strlen(bp) + 1; /* for the \0 */
if (n >= MAXHOSTNAMELEN) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
he->h_name = bp;
bp += n;
/* The qname can be abbreviated, but h_name is now absolute. */
qname = he->h_name;
}
ap = hed->host_aliases;
*ap = NULL;
he->h_aliases = hed->host_aliases;
hap = hed->h_addr_ptrs;
*hap = NULL;
he->h_addr_list = hed->h_addr_ptrs;
haveanswer = 0;
had_error = 0;
_dns_ttl_ = -1;
while (ancount-- > 0 && cp < eom && !had_error) {
n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
if ((n < 0) || !(*name_ok)(bp)) {
had_error++;
continue;
}
cp += n; /* name */
BOUNDS_CHECK(cp, 3 * INT16SZ + INT32SZ);
type = _getshort(cp);
cp += INT16SZ; /* type */
class = _getshort(cp);
cp += INT16SZ; /* class */
if (qtype == T_A && type == T_A)
_dns_ttl_ = _getlong(cp);
cp += INT32SZ; /* TTL */
n = _getshort(cp);
cp += INT16SZ; /* len */
BOUNDS_CHECK(cp, n);
erdata = cp + n;
if (class != C_IN) {
/* XXX - debug? syslog? */
cp += n;
continue; /* XXX - had_error++ ? */
}
if ((qtype == T_A || qtype == T_AAAA) && type == T_CNAME) {
if (ap >= &hed->host_aliases[_MAXALIASES-1])
continue;
n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
if ((n < 0) || !(*name_ok)(tbuf)) {
had_error++;
continue;
}
cp += n;
if (cp != erdata) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
/* Store alias. */
*ap++ = bp;
n = strlen(bp) + 1; /* for the \0 */
if (n >= MAXHOSTNAMELEN) {
had_error++;
continue;
}
bp += n;
/* Get canonical name. */
n = strlen(tbuf) + 1; /* for the \0 */
if (n > ep - bp || n >= MAXHOSTNAMELEN) {
had_error++;
continue;
}
strcpy(bp, tbuf);
he->h_name = bp;
bp += n;
continue;
}
if (qtype == T_PTR && type == T_CNAME) {
n = dn_expand(answer->buf, eom, cp, tbuf, sizeof tbuf);
if (n < 0 || !res_dnok(tbuf)) {
had_error++;
continue;
}
cp += n;
if (cp != erdata) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
/* Get canonical name. */
n = strlen(tbuf) + 1; /* for the \0 */
if (n > ep - bp || n >= MAXHOSTNAMELEN) {
had_error++;
continue;
}
strcpy(bp, tbuf);
tname = bp;
bp += n;
continue;
}
if (type != qtype) {
if (type != T_SIG && type != ns_t_dname)
syslog(LOG_NOTICE|LOG_AUTH,
"gethostby*.gethostanswer: asked for \"%s %s %s\", got type \"%s\"",
qname, p_class(C_IN), p_type(qtype),
p_type(type));
cp += n;
continue; /* XXX - had_error++ ? */
}
switch (type) {
case T_PTR:
if (strcasecmp(tname, bp) != 0) {
syslog(LOG_NOTICE|LOG_AUTH,
AskedForGot, qname, bp);
cp += n;
continue; /* XXX - had_error++ ? */
}
n = dn_expand(answer->buf, eom, cp, bp, ep - bp);
if ((n < 0) || !res_hnok(bp)) {
had_error++;
break;
}
#if MULTI_PTRS_ARE_ALIASES
cp += n;
if (cp != erdata) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
if (!haveanswer)
he->h_name = bp;
else if (ap < &hed->host_aliases[_MAXALIASES-1])
*ap++ = bp;
else
n = -1;
if (n != -1) {
n = strlen(bp) + 1; /* for the \0 */
if (n >= MAXHOSTNAMELEN) {
had_error++;
break;
}
bp += n;
}
break;
#else
he->h_name = bp;
if (statp->options & RES_USE_INET6) {
n = strlen(bp) + 1; /* for the \0 */
if (n >= MAXHOSTNAMELEN) {
had_error++;
break;
}
bp += n;
_map_v4v6_hostent(he, &bp, ep);
}
RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
return (0);
#endif
case T_A:
case T_AAAA:
if (strcasecmp(he->h_name, bp) != 0) {
syslog(LOG_NOTICE|LOG_AUTH,
AskedForGot, he->h_name, bp);
cp += n;
continue; /* XXX - had_error++ ? */
}
if (n != he->h_length) {
cp += n;
continue;
}
if (!haveanswer) {
int nn;
he->h_name = bp;
nn = strlen(bp) + 1; /* for the \0 */
bp += nn;
}
bp += sizeof(align) - ((u_long)bp % sizeof(align));
if (bp + n >= ep) {
dprintf("size (%d) too big\n", n, statp);
had_error++;
continue;
}
if (hap >= &hed->h_addr_ptrs[_MAXADDRS-1]) {
if (!toobig++)
dprintf("Too many addresses (%d)\n",
_MAXADDRS, statp);
cp += n;
continue;
}
memcpy(*hap++ = bp, cp, n);
bp += n;
cp += n;
if (cp != erdata) {
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
break;
default:
dprintf("Impossible condition (type=%d)\n", type,
statp);
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
/* BIND has abort() here, too risky on bad data */
}
if (!had_error)
haveanswer++;
}
if (haveanswer) {
*ap = NULL;
*hap = NULL;
# if defined(RESOLVSORT)
/*
* Note: we sort even if host can take only one address
* in its return structures - should give it the "best"
* address in that case, not some random one
*/
if (statp->nsort && haveanswer > 1 && qtype == T_A)
addrsort(hed->h_addr_ptrs, haveanswer, statp);
# endif /*RESOLVSORT*/
if (!he->h_name) {
n = strlen(qname) + 1; /* for the \0 */
if (n > ep - bp || n >= MAXHOSTNAMELEN)
goto no_recovery;
strcpy(bp, qname);
he->h_name = bp;
bp += n;
}
if (statp->options & RES_USE_INET6)
_map_v4v6_hostent(he, &bp, ep);
RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
return (0);
}
no_recovery:
RES_SET_H_ERRNO(statp, NO_RECOVERY);
return (-1);
}
/* XXX: for async DNS resolver in ypserv */
struct hostent *
__dns_getanswer(const char *answer, int anslen, const char *qname, int qtype)
{
struct hostent *he;
struct hostent_data *hed;
int error;
res_state statp;
statp = __res_state();
if ((he = __hostent_init()) == NULL ||
(hed = __hostent_data_init()) == NULL) {
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
return (NULL);
}
switch (qtype) {
case T_AAAA:
he->h_addrtype = AF_INET6;
he->h_length = NS_IN6ADDRSZ;
break;
case T_A:
default:
he->h_addrtype = AF_INET;
he->h_length = NS_INADDRSZ;
break;
}
error = gethostanswer((const querybuf *)answer, anslen, qname, qtype,
he, hed, statp);
return (error == 0) ? he : NULL;
}
int
_dns_gethostbyname(void *rval, void *cb_data, va_list ap)
{
const char *name;
int af;
char *buffer;
size_t buflen;
int *errnop, *h_errnop;
struct hostent *hptr, he;
struct hostent_data *hed;
querybuf *buf;
int n, type, error;
res_state statp;
name = va_arg(ap, const char *);
af = va_arg(ap, int);
hptr = va_arg(ap, struct hostent *);
buffer = va_arg(ap, char *);
buflen = va_arg(ap, size_t);
errnop = va_arg(ap, int *);
h_errnop = va_arg(ap, int *);
*((struct hostent **)rval) = NULL;
statp = __res_state();
if ((hed = __hostent_data_init()) == NULL) {
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
return (NS_NOTFOUND);
}
he.h_addrtype = af;
switch (af) {
case AF_INET:
he.h_length = NS_INADDRSZ;
type = T_A;
break;
case AF_INET6:
he.h_length = NS_IN6ADDRSZ;
type = T_AAAA;
break;
default:
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
errno = EAFNOSUPPORT;
return (NS_UNAVAIL);
}
if ((buf = malloc(sizeof(*buf))) == NULL) {
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
return (NS_NOTFOUND);
}
n = res_nsearch(statp, name, C_IN, type, buf->buf, sizeof(buf->buf));
if (n < 0) {
free(buf);
dprintf("res_nsearch failed (%d)\n", n, statp);
*h_errnop = statp->res_h_errno;
return (NS_NOTFOUND);
} else if (n > sizeof(buf->buf)) {
free(buf);
dprintf("static buffer is too small (%d)\n", n, statp);
*h_errnop = statp->res_h_errno;
return (NS_UNAVAIL);
}
error = gethostanswer(buf, n, name, type, &he, hed, statp);
free(buf);
if (error != 0) {
*h_errnop = statp->res_h_errno;
switch (statp->res_h_errno) {
case HOST_NOT_FOUND:
return (NS_NOTFOUND);
case TRY_AGAIN:
return (NS_TRYAGAIN);
default:
return (NS_UNAVAIL);
}
/*NOTREACHED*/
}
if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
*errnop = errno;
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
return (NS_RETURN);
}
RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
*((struct hostent **)rval) = hptr;
return (NS_SUCCESS);
}
int
_dns_gethostbyaddr(void *rval, void *cb_data, va_list ap)
{
const void *addr;
socklen_t len;
int af;
char *buffer;
size_t buflen;
int *errnop, *h_errnop;
const u_char *uaddr;
struct hostent *hptr, he;
struct hostent_data *hed;
int n;
querybuf *buf;
char qbuf[MAXDNAME+1], *qp;
res_state statp;
#ifdef SUNSECURITY
struct hostdata rhd;
struct hostent *rhe;
char **haddr;
u_long old_options;
char hname2[MAXDNAME+1], numaddr[46];
int ret_h_error;
#endif /*SUNSECURITY*/
addr = va_arg(ap, const void *);
len = va_arg(ap, socklen_t);
af = va_arg(ap, int);
hptr = va_arg(ap, struct hostent *);
buffer = va_arg(ap, char *);
buflen = va_arg(ap, size_t);
errnop = va_arg(ap, int *);
h_errnop = va_arg(ap, int *);
uaddr = (const u_char *)addr;
*((struct hostent **)rval) = NULL;
statp = __res_state();
if ((hed = __hostent_data_init()) == NULL) {
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
return (NS_NOTFOUND);
}
switch (af) {
case AF_INET:
(void) sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa",
(uaddr[3] & 0xff),
(uaddr[2] & 0xff),
(uaddr[1] & 0xff),
(uaddr[0] & 0xff));
break;
case AF_INET6:
qp = qbuf;
for (n = NS_IN6ADDRSZ - 1; n >= 0; n--) {
qp += SPRINTF((qp, "%x.%x.",
uaddr[n] & 0xf,
(uaddr[n] >> 4) & 0xf));
}
strlcat(qbuf, "ip6.arpa", sizeof(qbuf));
break;
default:
abort();
}
if ((buf = malloc(sizeof(*buf))) == NULL) {
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
return NS_NOTFOUND;
}
n = res_nquery(statp, qbuf, C_IN, T_PTR, (u_char *)buf->buf,
sizeof buf->buf);
if (n < 0) {
free(buf);
dprintf("res_nquery failed (%d)\n", n, statp);
*h_errnop = statp->res_h_errno;
return (NS_UNAVAIL);
}
if (n > sizeof buf->buf) {
free(buf);
dprintf("static buffer is too small (%d)\n", n, statp);
*h_errnop = statp->res_h_errno;
return (NS_UNAVAIL);
}
if (gethostanswer(buf, n, qbuf, T_PTR, &he, hed, statp) != 0) {
free(buf);
*h_errnop = statp->res_h_errno;
switch (statp->res_h_errno) {
case HOST_NOT_FOUND:
return (NS_NOTFOUND);
case TRY_AGAIN:
return (NS_TRYAGAIN);
default:
return (NS_UNAVAIL);
}
/*NOTREACHED*/
}
free(buf);
#ifdef SUNSECURITY
if (af == AF_INET) {
/*
* turn off search as the name should be absolute,
* 'localhost' should be matched by defnames
*/
strncpy(hname2, he.h_name, MAXDNAME);
hname2[MAXDNAME] = '\0';
old_options = statp->options;
statp->options &= ~RES_DNSRCH;
statp->options |= RES_DEFNAMES;
memset(&rhd, 0, sizeof rhd);
rhe = gethostbyname_r(hname2, &rhd.host, &rhd.data,
sizeof(rhd.data), &ret_h_error);
if (rhe == NULL) {
if (inet_ntop(af, addr, numaddr, sizeof(numaddr)) == NULL)
strlcpy(numaddr, "UNKNOWN", sizeof(numaddr));
syslog(LOG_NOTICE|LOG_AUTH,
"gethostbyaddr: No A record for %s (verifying [%s])",
hname2, numaddr);
statp->options = old_options;
RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
*h_errnop = statp->res_h_errno;
return (NS_NOTFOUND);
}
statp->options = old_options;
for (haddr = rhe->h_addr_list; *haddr; haddr++)
if (!memcmp(*haddr, addr, NS_INADDRSZ))
break;
if (!*haddr) {
if (inet_ntop(af, addr, numaddr, sizeof(numaddr)) == NULL)
strlcpy(numaddr, "UNKNOWN", sizeof(numaddr));
syslog(LOG_NOTICE|LOG_AUTH,
"gethostbyaddr: A record of %s != PTR record [%s]",
hname2, numaddr);
RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
*h_errnop = statp->res_h_errno;
return (NS_NOTFOUND);
}
}
#endif /*SUNSECURITY*/
he.h_addrtype = af;
he.h_length = len;
memcpy(hed->host_addr, uaddr, len);
hed->h_addr_ptrs[0] = (char *)hed->host_addr;
hed->h_addr_ptrs[1] = NULL;
if (af == AF_INET && (statp->options & RES_USE_INET6)) {
_map_v4v6_address((char*)hed->host_addr, (char*)hed->host_addr);
he.h_addrtype = AF_INET6;
he.h_length = NS_IN6ADDRSZ;
}
if (__copy_hostent(&he, hptr, buffer, buflen) != 0) {
*errnop = errno;
RES_SET_H_ERRNO(statp, NETDB_INTERNAL);
*h_errnop = statp->res_h_errno;
return (NS_RETURN);
}
RES_SET_H_ERRNO(statp, NETDB_SUCCESS);
*((struct hostent **)rval) = hptr;
return (NS_SUCCESS);
}
#ifdef RESOLVSORT
static void
addrsort(char **ap, int num, res_state res)
{
int i, j;
char **p;
short aval[_MAXADDRS];
int needsort = 0;
p = ap;
for (i = 0; i < num; i++, p++) {
for (j = 0 ; (unsigned)j < res->nsort; j++)
if (res->sort_list[j].addr.s_addr ==
(((struct in_addr *)(*p))->s_addr & res->sort_list[j].mask))
break;
aval[i] = j;
if (needsort == 0 && i > 0 && j < aval[i-1])
needsort = i;
}
if (!needsort)
return;
while (needsort < num) {
for (j = needsort - 1; j >= 0; j--) {
if (aval[j] > aval[j+1]) {
char *hp;
i = aval[j];
aval[j] = aval[j+1];
aval[j+1] = i;
hp = ap[j];
ap[j] = ap[j+1];
ap[j+1] = hp;
} else
break;
}
needsort++;
}
}
#endif
void
_sethostdnsent(int stayopen)
{
res_state statp;
statp = __res_state();
if ((statp->options & RES_INIT) == 0 && res_ninit(statp) == -1)
return;
if (stayopen)
statp->options |= RES_STAYOPEN | RES_USEVC;
}
void
_endhostdnsent()
{
res_state statp;
statp = __res_state();
statp->options &= ~(RES_STAYOPEN | RES_USEVC);
res_nclose(statp);
}