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- /*
- * Copyright (c) 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.
- */
- /*
- * Portions Copyright (c) 1996-1999 by Internet Software Consortium.
- *
- * 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.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
- * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
- * CONSORTIUM 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.
- */
- #include <assert.h>
- #include <sys/types.h>
- #include <sys/param.h>
- #include <netinet/in.h>
- #include <arpa/inet.h>
- #include <arpa/nameser.h>
- #include <ctype.h>
- #include <errno.h>
- #include <netdb.h>
- #include <resolv.h>
- #include <resolv/resolv-internal.h>
- #include <resolv/resolv_context.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <shlib-compat.h>
- #if PACKETSZ > 65536
- #define MAXPACKET PACKETSZ
- #else
- #define MAXPACKET 65536
- #endif
- #define QUERYSIZE (HFIXEDSZ + QFIXEDSZ + MAXCDNAME + 1)
- static int
- __res_context_querydomain (struct resolv_context *,
- const char *name, const char *domain,
- int class, int type, unsigned char *answer, int anslen,
- unsigned char **answerp, unsigned char **answerp2, int *nanswerp2,
- int *resplen2, int *answerp2_malloced);
- /* Formulate a normal query, send, and await answer. Returned answer
- is placed in supplied buffer ANSWER. Perform preliminary check of
- answer, returning success only if no error is indicated and the
- answer count is nonzero. Return the size of the response on
- success, -1 on error. Error number is left in h_errno.
- Caller must parse answer and determine whether it answers the
- question. */
- int
- __res_context_query (struct resolv_context *ctx, const char *name,
- int class, int type,
- unsigned char *answer, int anslen,
- unsigned char **answerp, unsigned char **answerp2,
- int *nanswerp2, int *resplen2, int *answerp2_malloced)
- {
- struct __res_state *statp = ctx->resp;
- HEADER *hp = (HEADER *) answer;
- HEADER *hp2;
- int n, use_malloc = 0;
- size_t bufsize = (type == T_QUERY_A_AND_AAAA ? 2 : 1) * QUERYSIZE;
- u_char *buf = alloca (bufsize);
- u_char *query1 = buf;
- int nquery1 = -1;
- u_char *query2 = NULL;
- int nquery2 = 0;
- again:
- hp->rcode = NOERROR; /* default */
- if (type == T_QUERY_A_AND_AAAA)
- {
- n = __res_context_mkquery (ctx, QUERY, name, class, T_A, NULL,
- query1, bufsize);
- if (n > 0)
- {
- if ((statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0)
- {
- /* Use RESOLV_EDNS_BUFFER_SIZE because the receive
- buffer can be reallocated. */
- n = __res_nopt (ctx, n, query1, bufsize,
- RESOLV_EDNS_BUFFER_SIZE);
- if (n < 0)
- goto unspec_nomem;
- }
- nquery1 = n;
- /* Align the buffer. */
- int npad = ((nquery1 + __alignof__ (HEADER) - 1)
- & ~(__alignof__ (HEADER) - 1)) - nquery1;
- if (n > bufsize - npad)
- {
- n = -1;
- goto unspec_nomem;
- }
- int nused = n + npad;
- query2 = buf + nused;
- n = __res_context_mkquery (ctx, QUERY, name, class, T_AAAA,
- NULL, query2, bufsize - nused);
- if (n > 0
- && (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0)
- /* Use RESOLV_EDNS_BUFFER_SIZE because the receive
- buffer can be reallocated. */
- n = __res_nopt (ctx, n, query2, bufsize,
- RESOLV_EDNS_BUFFER_SIZE);
- nquery2 = n;
- }
- unspec_nomem:;
- }
- else
- {
- n = __res_context_mkquery (ctx, QUERY, name, class, type, NULL,
- query1, bufsize);
- if (n > 0
- && (statp->options & (RES_USE_EDNS0|RES_USE_DNSSEC)) != 0)
- {
- /* Use RESOLV_EDNS_BUFFER_SIZE if the receive buffer
- can be reallocated. */
- size_t advertise;
- if (answerp == NULL)
- advertise = anslen;
- else
- advertise = RESOLV_EDNS_BUFFER_SIZE;
- n = __res_nopt (ctx, n, query1, bufsize, advertise);
- }
- nquery1 = n;
- }
- if (__glibc_unlikely (n <= 0) && !use_malloc) {
- /* Retry just in case res_nmkquery failed because of too
- short buffer. Shouldn't happen. */
- bufsize = (type == T_QUERY_A_AND_AAAA ? 2 : 1) * MAXPACKET;
- buf = malloc (bufsize);
- if (buf != NULL) {
- query1 = buf;
- use_malloc = 1;
- goto again;
- }
- }
- if (__glibc_unlikely (n <= 0)) {
- RES_SET_H_ERRNO(statp, NO_RECOVERY);
- if (use_malloc)
- free (buf);
- return (n);
- }
- assert (answerp == NULL || (void *) *answerp == (void *) answer);
- n = __res_context_send (ctx, query1, nquery1, query2, nquery2, answer,
- anslen, answerp, answerp2, nanswerp2, resplen2,
- answerp2_malloced);
- if (use_malloc)
- free (buf);
- if (n < 0) {
- RES_SET_H_ERRNO(statp, TRY_AGAIN);
- return (n);
- }
- if (answerp != NULL)
- /* __res_context_send might have reallocated the buffer. */
- hp = (HEADER *) *answerp;
- /* We simplify the following tests by assigning HP to HP2 or
- vice versa. It is easy to verify that this is the same as
- ignoring all tests of HP or HP2. */
- if (answerp2 == NULL || *resplen2 < (int) sizeof (HEADER))
- {
- hp2 = hp;
- }
- else
- {
- hp2 = (HEADER *) *answerp2;
- if (n < (int) sizeof (HEADER))
- {
- hp = hp2;
- }
- }
- /* Make sure both hp and hp2 are defined */
- assert((hp != NULL) && (hp2 != NULL));
- if ((hp->rcode != NOERROR || ntohs(hp->ancount) == 0)
- && (hp2->rcode != NOERROR || ntohs(hp2->ancount) == 0)) {
- switch (hp->rcode == NOERROR ? hp2->rcode : hp->rcode) {
- case NXDOMAIN:
- if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0)
- || (hp2->rcode == NOERROR
- && ntohs (hp2->ancount) != 0))
- goto success;
- RES_SET_H_ERRNO(statp, HOST_NOT_FOUND);
- break;
- case SERVFAIL:
- RES_SET_H_ERRNO(statp, TRY_AGAIN);
- break;
- case NOERROR:
- if (ntohs (hp->ancount) != 0
- || ntohs (hp2->ancount) != 0)
- goto success;
- RES_SET_H_ERRNO(statp, NO_DATA);
- break;
- case FORMERR:
- case NOTIMP:
- /* Servers must not reply to AAAA queries with
- NOTIMP etc but some of them do. */
- if ((hp->rcode == NOERROR && ntohs (hp->ancount) != 0)
- || (hp2->rcode == NOERROR
- && ntohs (hp2->ancount) != 0))
- goto success;
- /* FALLTHROUGH */
- case REFUSED:
- default:
- RES_SET_H_ERRNO(statp, NO_RECOVERY);
- break;
- }
- return (-1);
- }
- success:
- return (n);
- }
- libresolv_hidden_def (__res_context_query)
- /* Common part of res_nquery and res_query. */
- static int
- context_query_common (struct resolv_context *ctx,
- const char *name, int class, int type,
- unsigned char *answer, int anslen)
- {
- if (ctx == NULL)
- {
- RES_SET_H_ERRNO (&_res, NETDB_INTERNAL);
- return -1;
- }
- int result = __res_context_query (ctx, name, class, type, answer, anslen,
- NULL, NULL, NULL, NULL, NULL);
- __resolv_context_put (ctx);
- return result;
- }
- int
- res_nquery(res_state statp,
- const char *name, /* domain name */
- int class, int type, /* class and type of query */
- u_char *answer, /* buffer to put answer */
- int anslen) /* size of answer buffer */
- {
- return context_query_common
- (__resolv_context_get_override (statp), name, class, type, answer, anslen);
- }
- int
- res_query (const char *name, int class, int type,
- unsigned char *answer, int anslen)
- {
- return context_query_common
- (__resolv_context_get (), name, class, type, answer, anslen);
- }
- /* Formulate a normal query, send, and retrieve answer in supplied
- buffer. Return the size of the response on success, -1 on error.
- If enabled, implement search rules until answer or unrecoverable
- failure is detected. Error code, if any, is left in h_errno. */
- int
- __res_context_search (struct resolv_context *ctx,
- const char *name, int class, int type,
- unsigned char *answer, int anslen,
- unsigned char **answerp, unsigned char **answerp2,
- int *nanswerp2, int *resplen2, int *answerp2_malloced)
- {
- struct __res_state *statp = ctx->resp;
- const char *cp;
- HEADER *hp = (HEADER *) answer;
- char tmp[NS_MAXDNAME];
- u_int dots;
- int trailing_dot, ret, saved_herrno;
- int got_nodata = 0, got_servfail = 0, root_on_list = 0;
- int tried_as_is = 0;
- int searched = 0;
- __set_errno (0);
- RES_SET_H_ERRNO(statp, HOST_NOT_FOUND); /* True if we never query. */
- dots = 0;
- for (cp = name; *cp != '\0'; cp++)
- dots += (*cp == '.');
- trailing_dot = 0;
- if (cp > name && *--cp == '.')
- trailing_dot++;
- /* If there aren't any dots, it could be a user-level alias. */
- if (!dots && (cp = __res_context_hostalias
- (ctx, name, tmp, sizeof tmp))!= NULL)
- return __res_context_query (ctx, cp, class, type, answer,
- anslen, answerp, answerp2,
- nanswerp2, resplen2, answerp2_malloced);
- /*
- * If there are enough dots in the name, let's just give it a
- * try 'as is'. The threshold can be set with the "ndots" option.
- * Also, query 'as is', if there is a trailing dot in the name.
- */
- saved_herrno = -1;
- if (dots >= statp->ndots || trailing_dot) {
- ret = __res_context_querydomain (ctx, name, NULL, class, type,
- answer, anslen, answerp,
- answerp2, nanswerp2, resplen2,
- answerp2_malloced);
- if (ret > 0 || trailing_dot
- /* If the second response is valid then we use that. */
- || (ret == 0 && resplen2 != NULL && *resplen2 > 0))
- return (ret);
- saved_herrno = h_errno;
- tried_as_is++;
- if (answerp && *answerp != answer) {
- answer = *answerp;
- anslen = MAXPACKET;
- }
- if (answerp2 && *answerp2_malloced)
- {
- free (*answerp2);
- *answerp2 = NULL;
- *nanswerp2 = 0;
- *answerp2_malloced = 0;
- }
- }
- /*
- * We do at least one level of search if
- * - there is no dot and RES_DEFNAME is set, or
- * - there is at least one dot, there is no trailing dot,
- * and RES_DNSRCH is set.
- */
- if ((!dots && (statp->options & RES_DEFNAMES) != 0) ||
- (dots && !trailing_dot && (statp->options & RES_DNSRCH) != 0)) {
- int done = 0;
- for (size_t domain_index = 0; !done; ++domain_index) {
- const char *dname = __resolv_context_search_list
- (ctx, domain_index);
- if (dname == NULL)
- break;
- searched = 1;
- /* __res_context_querydoman concatenates name
- with dname with a "." in between. If we
- pass it in dname the "." we got from the
- configured default search path, we'll end
- up with "name..", which won't resolve.
- OTOH, passing it "" will result in "name.",
- which has the intended effect for both
- possible representations of the root
- domain. */
- if (dname[0] == '.')
- dname++;
- if (dname[0] == '\0')
- root_on_list++;
- ret = __res_context_querydomain
- (ctx, name, dname, class, type,
- answer, anslen, answerp, answerp2, nanswerp2,
- resplen2, answerp2_malloced);
- if (ret > 0 || (ret == 0 && resplen2 != NULL
- && *resplen2 > 0))
- return (ret);
- if (answerp && *answerp != answer) {
- answer = *answerp;
- anslen = MAXPACKET;
- }
- if (answerp2 && *answerp2_malloced)
- {
- free (*answerp2);
- *answerp2 = NULL;
- *nanswerp2 = 0;
- *answerp2_malloced = 0;
- }
- /*
- * If no server present, give up.
- * If name isn't found in this domain,
- * keep trying higher domains in the search list
- * (if that's enabled).
- * On a NO_DATA error, keep trying, otherwise
- * a wildcard entry of another type could keep us
- * from finding this entry higher in the domain.
- * If we get some other error (negative answer or
- * server failure), then stop searching up,
- * but try the input name below in case it's
- * fully-qualified.
- */
- if (errno == ECONNREFUSED) {
- RES_SET_H_ERRNO(statp, TRY_AGAIN);
- return (-1);
- }
- switch (statp->res_h_errno) {
- case NO_DATA:
- got_nodata++;
- /* FALLTHROUGH */
- case HOST_NOT_FOUND:
- /* keep trying */
- break;
- case TRY_AGAIN:
- if (hp->rcode == SERVFAIL) {
- /* try next search element, if any */
- got_servfail++;
- break;
- }
- /* FALLTHROUGH */
- default:
- /* anything else implies that we're done */
- done++;
- }
- /* if we got here for some reason other than DNSRCH,
- * we only wanted one iteration of the loop, so stop.
- */
- if ((statp->options & RES_DNSRCH) == 0)
- done++;
- }
- }
- /*
- * If the query has not already been tried as is then try it
- * unless RES_NOTLDQUERY is set and there were no dots.
- */
- if ((dots || !searched || (statp->options & RES_NOTLDQUERY) == 0)
- && !(tried_as_is || root_on_list)) {
- ret = __res_context_querydomain
- (ctx, name, NULL, class, type,
- answer, anslen, answerp, answerp2, nanswerp2,
- resplen2, answerp2_malloced);
- if (ret > 0 || (ret == 0 && resplen2 != NULL
- && *resplen2 > 0))
- return (ret);
- }
- /* if we got here, we didn't satisfy the search.
- * if we did an initial full query, return that query's H_ERRNO
- * (note that we wouldn't be here if that query had succeeded).
- * else if we ever got a nodata, send that back as the reason.
- * else send back meaningless H_ERRNO, that being the one from
- * the last DNSRCH we did.
- */
- if (answerp2 && *answerp2_malloced)
- {
- free (*answerp2);
- *answerp2 = NULL;
- *nanswerp2 = 0;
- *answerp2_malloced = 0;
- }
- if (saved_herrno != -1)
- RES_SET_H_ERRNO(statp, saved_herrno);
- else if (got_nodata)
- RES_SET_H_ERRNO(statp, NO_DATA);
- else if (got_servfail)
- RES_SET_H_ERRNO(statp, TRY_AGAIN);
- return (-1);
- }
- libresolv_hidden_def (__res_context_search)
- /* Common part of res_nsearch and res_search. */
- static int
- context_search_common (struct resolv_context *ctx,
- const char *name, int class, int type,
- unsigned char *answer, int anslen)
- {
- if (ctx == NULL)
- {
- RES_SET_H_ERRNO (&_res, NETDB_INTERNAL);
- return -1;
- }
- int result = __res_context_search (ctx, name, class, type, answer, anslen,
- NULL, NULL, NULL, NULL, NULL);
- __resolv_context_put (ctx);
- return result;
- }
- int
- res_nsearch(res_state statp,
- const char *name, /* domain name */
- int class, int type, /* class and type of query */
- u_char *answer, /* buffer to put answer */
- int anslen) /* size of answer */
- {
- return context_search_common
- (__resolv_context_get_override (statp), name, class, type, answer, anslen);
- }
- int
- res_search (const char *name, int class, int type,
- unsigned char *answer, int anslen)
- {
- return context_search_common
- (__resolv_context_get (), name, class, type, answer, anslen);
- }
- /* Perform a call on res_query on the concatenation of name and
- domain. */
- static int
- __res_context_querydomain (struct resolv_context *ctx,
- const char *name, const char *domain,
- int class, int type,
- unsigned char *answer, int anslen,
- unsigned char **answerp, unsigned char **answerp2,
- int *nanswerp2, int *resplen2,
- int *answerp2_malloced)
- {
- struct __res_state *statp = ctx->resp;
- char nbuf[MAXDNAME];
- const char *longname = nbuf;
- size_t n, d;
- if (domain == NULL) {
- n = strlen(name);
- /* Decrement N prior to checking it against MAXDNAME
- so that we detect a wrap to SIZE_MAX and return
- a reasonable error. */
- n--;
- if (n >= MAXDNAME - 1) {
- RES_SET_H_ERRNO(statp, NO_RECOVERY);
- return (-1);
- }
- longname = name;
- } else {
- n = strlen(name);
- d = strlen(domain);
- if (n + d + 1 >= MAXDNAME) {
- RES_SET_H_ERRNO(statp, NO_RECOVERY);
- return (-1);
- }
- sprintf(nbuf, "%s.%s", name, domain);
- }
- return __res_context_query (ctx, longname, class, type, answer,
- anslen, answerp, answerp2, nanswerp2,
- resplen2, answerp2_malloced);
- }
- /* Common part of res_nquerydomain and res_querydomain. */
- static int
- context_querydomain_common (struct resolv_context *ctx,
- const char *name, const char *domain,
- int class, int type,
- unsigned char *answer, int anslen)
- {
- if (ctx == NULL)
- {
- RES_SET_H_ERRNO (&_res, NETDB_INTERNAL);
- return -1;
- }
- int result = __res_context_querydomain (ctx, name, domain, class, type,
- answer, anslen,
- NULL, NULL, NULL, NULL, NULL);
- __resolv_context_put (ctx);
- return result;
- }
- int
- res_nquerydomain(res_state statp,
- const char *name,
- const char *domain,
- int class, int type, /* class and type of query */
- u_char *answer, /* buffer to put answer */
- int anslen) /* size of answer */
- {
- return context_querydomain_common
- (__resolv_context_get_override (statp),
- name, domain, class, type, answer, anslen);
- }
- int
- res_querydomain (const char *name, const char *domain, int class, int type,
- unsigned char *answer, int anslen)
- {
- return context_querydomain_common
- (__resolv_context_get (), name, domain, class, type, answer, anslen);
- }
- const char *
- __res_context_hostalias (struct resolv_context *ctx,
- const char *name, char *dst, size_t siz)
- {
- char *file, *cp1, *cp2;
- char buf[BUFSIZ];
- FILE *fp;
- if (ctx->resp->options & RES_NOALIASES)
- return (NULL);
- file = getenv("HOSTALIASES");
- if (file == NULL || (fp = fopen(file, "rce")) == NULL)
- return (NULL);
- setbuf(fp, NULL);
- buf[sizeof(buf) - 1] = '\0';
- while (fgets(buf, sizeof(buf), fp)) {
- for (cp1 = buf; *cp1 && !isspace(*cp1); ++cp1)
- ;
- if (!*cp1)
- break;
- *cp1 = '\0';
- if (ns_samename(buf, name) == 1) {
- while (isspace(*++cp1))
- ;
- if (!*cp1)
- break;
- for (cp2 = cp1 + 1; *cp2 && !isspace(*cp2); ++cp2)
- ;
- *cp2 = '\0';
- strncpy(dst, cp1, siz - 1);
- dst[siz - 1] = '\0';
- fclose(fp);
- return (dst);
- }
- }
- fclose(fp);
- return (NULL);
- }
- libresolv_hidden_def (__res_context_hostalias)
- /* Common part of res_hostalias and hostalias. */
- static const char *
- context_hostalias_common (struct resolv_context *ctx,
- const char *name, char *dst, size_t siz)
- {
- if (ctx == NULL)
- {
- RES_SET_H_ERRNO (&_res, NETDB_INTERNAL);
- return NULL;
- }
- const char *result = __res_context_hostalias (ctx, name, dst, siz);
- __resolv_context_put (ctx);
- return result;
- }
- const char *
- res_hostalias (res_state statp, const char *name, char *dst, size_t siz)
- {
- return context_hostalias_common
- (__resolv_context_get_override (statp), name, dst, siz);
- }
- const char *
- hostalias (const char *name)
- {
- static char abuf[MAXDNAME];
- return context_hostalias_common
- (__resolv_context_get (), name, abuf, sizeof (abuf));
- }
- #if SHLIB_COMPAT (libresolv, GLIBC_2_0, GLIBC_2_2)
- # undef res_query
- # undef res_querydomain
- # undef res_search
- weak_alias (__res_query, res_query);
- weak_alias (__res_querydomain, res_querydomain);
- weak_alias (__res_search, res_search);
- #endif
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