Edit File: diff.h
/* * Copyright (C) Internet Systems Consortium, Inc. ("ISC") * * This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. * * See the COPYRIGHT file distributed with this work for additional * information regarding copyright ownership. */ #ifndef DNS_DIFF_H #define DNS_DIFF_H 1 /***** ***** Module Info *****/ /*! \file dns/diff.h * \brief * A diff is a convenience type representing a list of changes to be * made to a database. */ /*** *** Imports ***/ #include <isc/lang.h> #include <isc/magic.h> #include <dns/name.h> #include <dns/rdata.h> #include <dns/types.h> /*** *** Types ***/ /*% * A dns_difftuple_t represents a single RR being added or deleted. * The RR type and class are in the 'rdata' member; the class is always * the real one, not a DynDNS meta-class, so that the rdatas can be * compared using dns_rdata_compare(). The TTL is significant * even for deletions, because a deletion/addition pair cannot * be canceled out if the TTL differs (it might be an explicit * TTL update). * * Tuples are also used to represent complete RRs with owner * names for a couple of other purposes, such as the * individual RRs of a "RRset exists (value dependent)" * prerequisite set. In this case, op==DNS_DIFFOP_EXISTS, * and the TTL is ignored. * * DNS_DIFFOP_*RESIGN will cause the 'resign' attribute of the resulting * RRset to be recomputed to be 'resign' seconds before the earliest RRSIG * timeexpire. */ typedef enum { DNS_DIFFOP_ADD = 0, /*%< Add an RR. */ DNS_DIFFOP_DEL = 1, /*%< Delete an RR. */ DNS_DIFFOP_EXISTS = 2, /*%< Assert RR existence. */ DNS_DIFFOP_ADDRESIGN = 4, /*%< ADD + RESIGN. */ DNS_DIFFOP_DELRESIGN = 5 /*%< DEL + RESIGN. */ } dns_diffop_t; typedef struct dns_difftuple dns_difftuple_t; #define DNS_DIFFTUPLE_MAGIC ISC_MAGIC('D','I','F','T') #define DNS_DIFFTUPLE_VALID(t) ISC_MAGIC_VALID(t, DNS_DIFFTUPLE_MAGIC) struct dns_difftuple { unsigned int magic; isc_mem_t *mctx; dns_diffop_t op; dns_name_t name; dns_ttl_t ttl; dns_rdata_t rdata; ISC_LINK(dns_difftuple_t) link; /* Variable-size name data and rdata follows. */ }; /*% * A dns_diff_t represents a set of changes being applied to * a zone. Diffs are also used to represent "RRset exists * (value dependent)" prerequisites. */ typedef struct dns_diff dns_diff_t; #define DNS_DIFF_MAGIC ISC_MAGIC('D','I','F','F') #define DNS_DIFF_VALID(t) ISC_MAGIC_VALID(t, DNS_DIFF_MAGIC) struct dns_diff { unsigned int magic; isc_mem_t * mctx; ISC_LIST(dns_difftuple_t) tuples; }; /* Type of comparison function for sorting diffs. */ typedef int dns_diff_compare_func(const void *, const void *); /*** *** Functions ***/ ISC_LANG_BEGINDECLS /**************************************************************************/ /* * Manipulation of diffs and tuples. */ isc_result_t dns_difftuple_create(isc_mem_t *mctx, dns_diffop_t op, dns_name_t *name, dns_ttl_t ttl, dns_rdata_t *rdata, dns_difftuple_t **tp); /*%< * Create a tuple. Deep copies are made of the name and rdata, so * they need not remain valid after the call. * * Requires: *\li *tp != NULL && *tp == NULL. * * Returns: *\li ISC_R_SUCCESS * \li ISC_R_NOMEMORY */ void dns_difftuple_free(dns_difftuple_t **tp); /*%< * Free a tuple. * * Requires: * \li **tp is a valid tuple. * * Ensures: * \li *tp == NULL * \li All memory used by the tuple is freed. */ isc_result_t dns_difftuple_copy(dns_difftuple_t *orig, dns_difftuple_t **copyp); /*%< * Copy a tuple. * * Requires: * \li 'orig' points to a valid tuple *\li copyp != NULL && *copyp == NULL */ void dns_diff_init(isc_mem_t *mctx, dns_diff_t *diff); /*%< * Initialize a diff. * * Requires: * \li 'diff' points to an uninitialized dns_diff_t * \li allocated by the caller. * * Ensures: * \li '*diff' is a valid, empty diff. */ void dns_diff_clear(dns_diff_t *diff); /*%< * Clear a diff, destroying all its tuples. * * Requires: * \li 'diff' points to a valid dns_diff_t. * * Ensures: * \li Any tuples in the diff are destroyed. * The diff now empty, but it is still valid * and may be reused without calling dns_diff_init * again. The only memory used is that of the * dns_diff_t structure itself. * * Notes: * \li Managing the memory of the dns_diff_t structure itself * is the caller's responsibility. */ void dns_diff_append(dns_diff_t *diff, dns_difftuple_t **tuple); /*%< * Append a single tuple to a diff. * *\li 'diff' is a valid diff. * \li '*tuple' is a valid tuple. * * Ensures: *\li *tuple is NULL. *\li The tuple has been freed, or will be freed when the diff is cleared. */ void dns_diff_appendminimal(dns_diff_t *diff, dns_difftuple_t **tuple); /*%< * Append 'tuple' to 'diff', removing any duplicate * or conflicting updates as needed to create a minimal diff. * * Requires: *\li 'diff' is a minimal diff. * * Ensures: *\li 'diff' is still a minimal diff. * \li *tuple is NULL. * \li The tuple has been freed, or will be freed when the diff is cleared. * */ isc_result_t dns_diff_sort(dns_diff_t *diff, dns_diff_compare_func *compare); /*%< * Sort 'diff' in-place according to the comparison function 'compare'. */ isc_result_t dns_diff_apply(dns_diff_t *diff, dns_db_t *db, dns_dbversion_t *ver); isc_result_t dns_diff_applysilently(dns_diff_t *diff, dns_db_t *db, dns_dbversion_t *ver); /*%< * Apply 'diff' to the database 'db'. * * dns_diff_apply() logs warnings about updates with no effect or * with inconsistent TTLs; dns_diff_applysilently() does not. * * For efficiency, the diff should be sorted by owner name. * If it is not sorted, operation will still be correct, * but less efficient. * * Requires: *\li *diff is a valid diff (possibly empty), containing * tuples of type #DNS_DIFFOP_ADD and/or * For #DNS_DIFFOP_DEL tuples, the TTL is ignored. * */ isc_result_t dns_diff_load(dns_diff_t *diff, dns_addrdatasetfunc_t addfunc, void *add_private); /*%< * Like dns_diff_apply, but for use when loading a new database * instead of modifying an existing one. This bypasses the * database transaction mechanisms. * * Requires: *\li 'addfunc' is a valid dns_addradatasetfunc_t obtained from * dns_db_beginload() * *\li 'add_private' points to a corresponding dns_dbload_t * * (XXX why is it a void pointer, then?) */ isc_result_t dns_diff_print(dns_diff_t *diff, FILE *file); /*%< * Print the differences to 'file' or if 'file' is NULL via the * logging system. * * Require: *\li 'diff' to be valid. *\li 'file' to refer to a open file or NULL. * * Returns: *\li #ISC_R_SUCCESS *\li #ISC_R_NOMEMORY *\li #ISC_R_UNEXPECTED *\li any error from dns_rdataset_totext() */ ISC_LANG_ENDDECLS #endif /* DNS_DIFF_H */