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/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2005, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*
* DNS SRV record support
*/
#ifndef _ASTERISK_SRV_H
#define _ASTERISK_SRV_H
/*!
\file srv.h
\brief Support for DNS SRV records, used in to locate SIP services.
\note Note: This SRV record support will respect the priority and
weight elements of the records that are returned, but there are
no provisions for retrying or failover between records.
*/
/*!\brief An opaque type, for lookup usage */
struct srv_context;
/*!\brief Retrieve set of SRV lookups, in order
* \param[in] context A pointer in which to hold the result
* \param[in] service The service name to look up
* \param[out] host Result host
* \param[out] port Associated TCP portnum
* \retval -1 Query failed
* \retval 0 Result exists in host and port
* \retval 1 No more results
*/
extern int ast_srv_lookup(struct srv_context **context, const char *service, const char **host, unsigned short *port);
/*!\brief Cleanup resources associated with ast_srv_lookup
* \param context Pointer passed into ast_srv_lookup
*/
void ast_srv_cleanup(struct srv_context **context);
/*! Lookup entry in SRV records Returns 1 if found, 0 if not found, -1 on hangup
Only do SRV record lookup if you get a domain without a port. If you get a port #, it's a DNS host name.
*/
/*! \param chan Ast channel
\param host host name (return value)
\param hostlen Length of string "host"
\param port Port number (return value)
\param service Service tag for SRV lookup (like "_sip._udp" or "_stun._udp"
*/
extern int ast_get_srv(struct ast_channel *chan, char *host, int hostlen, int *port, const char *service);
/*!
* \brief Get the number of records for a given SRV context
*
* \details
* This is meant to be used after calling ast_srv_lookup, so that
* one may retrieve the number of records returned during a specific
* SRV lookup.
*
* \param context The context returned by ast_srv_lookup
* \return Number of records in context
*/
unsigned int ast_srv_get_record_count(struct srv_context *context);
/*!
* \brief Retrieve details from a specific SRV record
*
* \details
* After calling ast_srv_lookup, the srv_context will contain
* the data from several records. You can retrieve the data
* of a specific one by asking for a specific record number. The
* records are sorted based on priority and secondarily based on
* weight. See RFC 2782 for the exact sorting rules.
*
* \param context The context returned by ast_srv_lookup
* \param record_num The 1-indexed record number to retrieve
* \param[out] host The host portion of the record
* \param[out] port The port portion of the record
* \param[out] priority The priority portion of the record
* \param[out] weight The weight portion of the record
* \retval -1 Failed to retrieve information. Likely due to an out of
* range record_num
* \retval 0 Success
*/
int ast_srv_get_nth_record(struct srv_context *context, int record_num, const char **host,
unsigned short *port, unsigned short *priority, unsigned short *weight);
#endif /* _ASTERISK_SRV_H */
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