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bind9/lib/dns/include/dns/lookup.h
2009-01-17 23:47:43 +00:00

138 lines
3.4 KiB
C

/*
* Copyright (C) 2004-2007, 2009 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 2000, 2001 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or 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 ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC 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.
*/
/* $Id: lookup.h,v 1.14 2009/01/17 23:47:43 tbox Exp $ */
#ifndef DNS_LOOKUP_H
#define DNS_LOOKUP_H 1
/*****
***** Module Info
*****/
/*! \file dns/lookup.h
* \brief
* The lookup module performs simple DNS lookups. It implements
* the full resolver algorithm, both looking for local data and
* resolving external names as necessary.
*
* MP:
*\li The module ensures appropriate synchronization of data structures it
* creates and manipulates.
*
* Reliability:
*\li No anticipated impact.
*
* Resources:
*\li TBS
*
* Security:
*\li No anticipated impact.
*
* Standards:
*\li RFCs: 1034, 1035, 2181, TBS
*\li Drafts: TBS
*/
#include <isc/lang.h>
#include <isc/event.h>
#include <dns/types.h>
ISC_LANG_BEGINDECLS
/*%
* A 'dns_lookupevent_t' is returned when a lookup completes.
* The sender field will be set to the lookup that completed. If 'result'
* is ISC_R_SUCCESS, then 'names' will contain a list of names associated
* with the address. The recipient of the event must not change the list
* and must not refer to any of the name data after the event is freed.
*/
typedef struct dns_lookupevent {
ISC_EVENT_COMMON(struct dns_lookupevent);
isc_result_t result;
dns_name_t *name;
dns_rdataset_t *rdataset;
dns_rdataset_t *sigrdataset;
dns_db_t *db;
dns_dbnode_t *node;
} dns_lookupevent_t;
isc_result_t
dns_lookup_create(isc_mem_t *mctx, dns_name_t *name, dns_rdatatype_t type,
dns_view_t *view, unsigned int options, isc_task_t *task,
isc_taskaction_t action, void *arg, dns_lookup_t **lookupp);
/*%<
* Finds the rrsets matching 'name' and 'type'.
*
* Requires:
*
*\li 'mctx' is a valid mctx.
*
*\li 'name' is a valid name.
*
*\li 'view' is a valid view which has a resolver.
*
*\li 'task' is a valid task.
*
*\li lookupp != NULL && *lookupp == NULL
*
* Returns:
*
*\li ISC_R_SUCCESS
*\li ISC_R_NOMEMORY
*
*\li Any resolver-related error (e.g. ISC_R_SHUTTINGDOWN) may also be
* returned.
*/
void
dns_lookup_cancel(dns_lookup_t *lookup);
/*%<
* Cancel 'lookup'.
*
* Notes:
*
*\li If 'lookup' has not completed, post its LOOKUPDONE event with a
* result code of ISC_R_CANCELED.
*
* Requires:
*
*\li 'lookup' is a valid lookup.
*/
void
dns_lookup_destroy(dns_lookup_t **lookupp);
/*%<
* Destroy 'lookup'.
*
* Requires:
*
*\li '*lookupp' is a valid lookup.
*
*\li The caller has received the LOOKUPDONE event (either because the
* lookup completed or because dns_lookup_cancel() was called).
*
* Ensures:
*
*\li *lookupp == NULL.
*/
ISC_LANG_ENDDECLS
#endif /* DNS_LOOKUP_H */