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#ifndef foorrhfoo
#define foorrhfoo
/* $Id$ */
/***
This file is part of avahi.
avahi is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
avahi is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with avahi; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
USA.
***/
/** \file rr.h Functions and definitions for manipulating DNS resource record (RR) data. */
#include <avahi-common/strlst.h>
#include <avahi-common/address.h>
#include <avahi-common/cdecl.h>
#include <inttypes.h>
#include <sys/types.h>
AVAHI_C_DECL_BEGIN
/** DNS record types, see RFC 1035 */
enum {
AVAHI_DNS_TYPE_A = 0x01,
AVAHI_DNS_TYPE_NS = 0x02,
AVAHI_DNS_TYPE_CNAME = 0x05,
AVAHI_DNS_TYPE_SOA = 0x06,
AVAHI_DNS_TYPE_PTR = 0x0C,
AVAHI_DNS_TYPE_HINFO = 0x0D,
AVAHI_DNS_TYPE_MX = 0x0F,
AVAHI_DNS_TYPE_TXT = 0x10,
AVAHI_DNS_TYPE_AAAA = 0x1C,
AVAHI_DNS_TYPE_SRV = 0x21,
AVAHI_DNS_TYPE_ANY = 0xFF /**< Special query type for requesting all records */
};
/** DNS record classes, see RFC 1035 */
enum {
AVAHI_DNS_CLASS_IN = 0x01, /**< Probably the only class we will ever use */
AVAHI_DNS_CLASS_ANY = 0xFF, /**< Special query type for requesting all records */
AVAHI_DNS_CACHE_FLUSH = 0x8000, /**< Not really a class but a bit which may be set in response packets, see mDNS spec for more information */
AVAHI_DNS_UNICAST_RESPONSE = 0x8000 /**< Not really a class but a bit which may be set in query packets, see mDNS spec for more information */
};
/** The default TTL for RRs which contain a host name of some kind. */
#define AVAHI_DEFAULT_TTL_HOST_NAME (120)
/** The default TTL for all other records. */
#define AVAHI_DEFAULT_TTL (75*60)
/** Encapsulates a DNS query key consisting of class, type and
name. Use avahi_key_ref()/avahi_key_unref() for manipulating the
reference counter. The structure is intended to be treated as "immutable", no
changes should be imposed after creation */
typedef struct {
int ref; /**< Reference counter */
char *name; /**< Record name */
uint16_t clazz; /**< Record class, one of the AVAHI_DNS_CLASS_xxx constants */
uint16_t type; /**< Record type, one of the AVAHI_DNS_TYPE_xxx constants */
} AvahiKey;
/** Encapsulates a DNS resource record. The structure is intended to
* be treated as "immutable", no changes should be imposed after
* creation. */
typedef struct {
int ref; /**< Reference counter */
AvahiKey *key; /**< Reference to the query key of thsi record */
uint32_t ttl; /**< DNS TTL of this record */
union {
struct {
void* data;
uint16_t size;
} generic; /**< Generic record data for unknown types */
struct {
uint16_t priority;
uint16_t weight;
uint16_t port;
char *name;
} srv; /**< Data for SRV records */
struct {
char *name;
} ptr; /**< Data for PTR an CNAME records */
struct {
char *cpu;
char *os;
} hinfo; /**< Data for HINFO records */
struct {
AvahiStringList *string_list;
} txt; /**< Data for TXT records */
struct {
AvahiIPv4Address address;
} a; /**< Data for A records */
struct {
AvahiIPv6Address address;
} aaaa; /**< Data for AAAA records */
} data; /**< Record data */
} AvahiRecord;
/** Create a new AvahiKey object. The reference counter will be set to 1. */
AvahiKey *avahi_key_new(const char *name, uint16_t clazz, uint16_t type);
/** Increase the reference counter of an AvahiKey object by one */
AvahiKey *avahi_key_ref(AvahiKey *k);
/** Decrease the reference counter of an AvahiKey object by one */
void avahi_key_unref(AvahiKey *k);
/** Check whether two AvahiKey object contain the same
* data. AVAHI_DNS_CLASS_ANY/AVAHI_DNS_TYPE_ANY are treated like any
* other class/type. */
int avahi_key_equal(const AvahiKey *a, const AvahiKey *b);
/** Match a key to a key pattern. The pattern has a type of
AVAHI_DNS_CLASS_ANY, the classes are taken to be equal. Same for the
type. If the pattern has neither class nor type with ANY constants,
this function is identical to avahi_key_equal(). In contrast to
avahi_equal() this function is not commutative. */
int avahi_key_pattern_match(const AvahiKey *pattern, const AvahiKey *k);
/** Check whether a key is a pattern key, i.e. the class/type has a
* value of AVAHI_DNS_CLASS_ANY/AVAHI_DNS_TYPE_ANY */
int avahi_key_is_pattern(const AvahiKey *k);
/** Return a numeric hash value for a key for usage in hash tables. */
unsigned avahi_key_hash(const AvahiKey *k);
/** Create a new record object. Record data should be filled in right after creation. The reference counter is set to 1. */
AvahiRecord *avahi_record_new(AvahiKey *k, uint32_t ttl);
/** Create a new record object. Record data should be filled in right after creation. The reference counter is set to 1. */
AvahiRecord *avahi_record_new_full(const char *name, uint16_t clazz, uint16_t type, uint32_t ttl);
/** Increase the reference counter of an AvahiRecord by one. */
AvahiRecord *avahi_record_ref(AvahiRecord *r);
/** Decrease the reference counter of an AvahiRecord by one. */
void avahi_record_unref(AvahiRecord *r);
/** Return a textual representation of the specified DNS class. The
* returned pointer points to a read only internal string. */
const char *avahi_dns_class_to_string(uint16_t clazz);
/** Return a textual representation of the specified DNS class. The
* returned pointer points to a read only internal string. */
const char *avahi_dns_type_to_string(uint16_t type);
/** Create a textual representation of the specified key. avahi_free() the
* result! */
char *avahi_key_to_string(const AvahiKey *k);
/** Create a textual representation of the specified record, similar
* in style to BIND zone file data. avahi_free() the result! */
char *avahi_record_to_string(const AvahiRecord *r);
/** Check whether two records are equal (regardless of the TTL */
int avahi_record_equal_no_ttl(const AvahiRecord *a, const AvahiRecord *b);
/** Make a deep copy of an AvahiRecord object */
AvahiRecord *avahi_record_copy(AvahiRecord *r);
/** Returns a maximum estimate for the space that is needed to store
* this key in a DNS packet. */
size_t avahi_key_get_estimate_size(AvahiKey *k);
/** Returns a maximum estimate for the space that is needed to store
* the record in a DNS packet. */
size_t avahi_record_get_estimate_size(AvahiRecord *r);
/** Do a mDNS spec conforming lexicographical comparison of the two
* records. Return a negative value if a < b, a positive if a > b,
* zero if equal. */
int avahi_record_lexicographical_compare(AvahiRecord *a, AvahiRecord *b);
/** Return 1 if the specified record is an mDNS goodbye record. i.e. TTL is zero. */
int avahi_record_is_goodbye(AvahiRecord *r);
/** Check whether the specified key is valid */
int avahi_key_is_valid(AvahiKey *k);
/** Check whether the specified record is valid */
int avahi_record_is_valid(AvahiRecord *r);
AVAHI_C_DECL_END
#endif
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