/* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * 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: rdataset.h,v 1.15 2022/06/26 09:43:39 florian Exp $ */ #ifndef DNS_RDATASET_H #define DNS_RDATASET_H 1 /***** ***** Module Info *****/ /*! \file dns/rdataset.h * \brief * A DNS rdataset is a handle that can be associated with a collection of * rdata all having a common owner name, class, and type. * * The dns_rdataset_t type is like a "virtual class". To actually use * rdatasets, an implementation of the method suite (e.g. "slabbed rdata") is * required. * * XXX <more> XXX * * MP: *\li Clients of this module must impose any required synchronization. * * Reliability: *\li No anticipated impact. * * Resources: *\li TBS * * Security: *\li No anticipated impact. * * Standards: *\li None. */ #include <dns/types.h> typedef enum { dns_rdatasetadditional_fromauth, dns_rdatasetadditional_fromcache, dns_rdatasetadditional_fromglue } dns_rdatasetadditional_t; typedef struct dns_rdatasetmethods { void (*disassociate)(dns_rdataset_t *rdataset); isc_result_t (*first)(dns_rdataset_t *rdataset); isc_result_t (*next)(dns_rdataset_t *rdataset); void (*current)(dns_rdataset_t *rdataset, dns_rdata_t *rdata); void (*clone)(dns_rdataset_t *source, dns_rdataset_t *target); unsigned int (*count)(dns_rdataset_t *rdataset); } dns_rdatasetmethods_t; /*% * Direct use of this structure by clients is strongly discouraged, except * for the 'link' field which may be used however the client wishes. The * 'private', 'current', and 'index' fields MUST NOT be changed by clients. * rdataset implementations may change any of the fields. */ struct dns_rdataset { dns_rdatasetmethods_t * methods; ISC_LINK(dns_rdataset_t) link; /* * XXX do we need these, or should they be retrieved by methods? * Leaning towards the latter, since they are not frequently required * once you have the rdataset. */ dns_rdataclass_t rdclass; dns_rdatatype_t type; dns_ttl_t ttl; dns_rdatatype_t covers; /* * attributes */ unsigned int attributes; /*% * the counter provides the starting point in the "cyclic" order. * The value UINT32_MAX has a special meaning of "picking up a * random value." in order to take care of databases that do not * increment the counter. */ uint32_t count; /*@{*/ /*% * These are for use by the rdataset implementation, and MUST NOT * be changed by clients. */ void * private1; void * private2; /*@}*/ }; /*! * \def DNS_RDATASETATTR_RENDERED * Used by message.c to indicate that the rdataset was rendered. */ #define DNS_RDATASETATTR_QUESTION 0x00000001 #define DNS_RDATASETATTR_RENDERED 0x00000002 /*%< Used by message.c */ void dns_rdataset_init(dns_rdataset_t *rdataset); /*%< * Make 'rdataset' a valid, disassociated rdataset. * * Requires: *\li 'rdataset' is not NULL. * * Ensures: *\li 'rdataset' is a valid, disassociated rdataset. */ void dns_rdataset_disassociate(dns_rdataset_t *rdataset); /*%< * Disassociate 'rdataset' from its rdata, allowing it to be reused. * * Notes: *\li The client must ensure it has no references to rdata in the rdataset * before disassociating. * * Requires: *\li 'rdataset' is a valid, associated rdataset. * * Ensures: *\li 'rdataset' is a valid, disassociated rdataset. */ int dns_rdataset_isassociated(dns_rdataset_t *rdataset); /*%< * Is 'rdataset' associated? * * Requires: *\li 'rdataset' is a valid rdataset. * * Returns: *\li #1 'rdataset' is associated. *\li #0 'rdataset' is not associated. */ void dns_rdataset_makequestion(dns_rdataset_t *rdataset, dns_rdataclass_t rdclass, dns_rdatatype_t type); /*%< * Make 'rdataset' a valid, associated, question rdataset, with a * question class of 'rdclass' and type 'type'. * * Notes: *\li Question rdatasets have a class and type, but no rdata. * * Requires: *\li 'rdataset' is a valid, disassociated rdataset. * * Ensures: *\li 'rdataset' is a valid, associated, question rdataset. */ isc_result_t dns_rdataset_first(dns_rdataset_t *rdataset); /*%< * Move the rdata cursor to the first rdata in the rdataset (if any). * * Requires: *\li 'rdataset' is a valid, associated rdataset. * * Returns: *\li #ISC_R_SUCCESS *\li #ISC_R_NOMORE There are no rdata in the set. */ isc_result_t dns_rdataset_next(dns_rdataset_t *rdataset); /*%< * Move the rdata cursor to the next rdata in the rdataset (if any). * * Requires: *\li 'rdataset' is a valid, associated rdataset. * * Returns: *\li #ISC_R_SUCCESS *\li #ISC_R_NOMORE There are no more rdata in the set. */ void dns_rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata); /*%< * Make 'rdata' refer to the current rdata. * * Notes: * *\li The data returned in 'rdata' is valid for the life of the * rdataset; in particular, subsequent changes in the cursor position * do not invalidate 'rdata'. * * Requires: *\li 'rdataset' is a valid, associated rdataset. * *\li The rdata cursor of 'rdataset' is at a valid location (i.e. the * result of last call to a cursor movement command was ISC_R_SUCCESS). * * Ensures: *\li 'rdata' refers to the rdata at the rdata cursor location of *\li 'rdataset'. */ isc_result_t dns_rdataset_totext(dns_rdataset_t *rdataset, dns_name_t *owner_name, int omit_final_dot, int question, isc_buffer_t *target); /*%< * Convert 'rdataset' to text format, storing the result in 'target'. * * Notes: *\li The rdata cursor position will be changed. * *\li The 'question' flag should normally be #0. If it is * #1, the TTL and rdata fields are not printed. This is * for use when printing an rdata representing a question section. * *\li This interface is deprecated; use dns_master_rdatasettottext() * and/or dns_master_questiontotext() instead. * * Requires: *\li 'rdataset' is a valid rdataset. * *\li 'rdataset' is not empty. */ isc_result_t dns_rdataset_towire(dns_rdataset_t *rdataset, dns_name_t *owner_name, dns_compress_t *cctx, isc_buffer_t *target, unsigned int *countp); /*%< * Convert 'rdataset' to wire format, compressing names as specified * in 'cctx', and storing the result in 'target'. * * Notes: *\li The rdata cursor position will be changed. * *\li The number of RRs added to target will be added to *countp. * * Requires: *\li 'rdataset' is a valid rdataset. * *\li 'rdataset' is not empty. * *\li 'countp' is a valid pointer. * * Ensures: *\li On a return of ISC_R_SUCCESS, 'target' contains a wire format * for the data contained in 'rdataset'. Any error return leaves * the buffer unchanged. * *\li *countp has been incremented by the number of RRs added to * target. * * Returns: *\li #ISC_R_SUCCESS - all ok *\li #ISC_R_NOSPACE - 'target' doesn't have enough room * *\li Any error returned by dns_rdata_towire(), dns_rdataset_next(), * dns_name_towire(). */ isc_result_t dns_rdataset_towiresorted(dns_rdataset_t *rdataset, const dns_name_t *owner_name, dns_compress_t *cctx, isc_buffer_t *target, unsigned int *countp); /*%< * Like dns_rdataset_towire(), but sorting the rdatasets according to * the integer value returned by 'order' when called with the rdataset * and 'order_arg' as arguments. * * Requires: *\li All the requirements of dns_rdataset_towire(), and * that order_arg is NULL if and only if order is NULL. */ #endif /* DNS_RDATASET_H */
