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/*
* Copyright (c) 1985 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
/*static char *sccsid = "from: @(#)res_query.c 6.22 (Berkeley) 3/19/91";*/
static char *rcsid = "$Id$";
#endif /* LIBC_SCCS and not lint */
#include <pthread.h>
#include <resolv.h>
#include <netdb.h>
#include "res_internal.h"
#if PACKETSZ > 1024
#define MAXPACKET PACKETSZ
#else
#define MAXPACKET 1024
#endif
int res_query(char *name, int class, int type, unsigned char *answer,
int anslen)
{
struct res_data *data;
char buf[MAXPACKET];
int result;
HEADER *hp;
data = _res_init();
if (!data)
return -1;
/* Make the query. */
result = res_mkquery(QUERY, name, class, type, NULL, 0, NULL, buf,
sizeof(buf));
if (result <= 0) {
data->errval = NO_RECOVERY;
return result;
}
result = res_send(buf, result, (char *) answer, anslen);
if (result < 0) {
data->errval = TRY_AGAIN;
return result;
}
hp = (HEADER *) answer;
if (hp->rcode == NOERROR && ntohs(hp->ancount) != 0)
return result;
/* Translate the error code and return. */
switch(hp->rcode) {
case NOERROR:
data->errval = NO_DATA;
break;
case SERVFAIL:
data->errval = TRY_AGAIN;
break;
case NXDOMAIN:
data->errval = HOST_NOT_FOUND;
break;
default:
data->errval = NO_RECOVERY;
break;
}
return -1;
}
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